--- /dev/null
+From 0668bc44a42672626666e4f66aa1f2c22528e8a5 Mon Sep 17 00:00:00 2001
+From: Abhishek Sahu <absahu@codeaurora.org>
+Date: Mon, 12 Mar 2018 18:44:50 +0530
+Subject: [PATCH 01/13] i2c: qup: fix copyrights and update to SPDX identifier
+
+The file has been updated from 2016 to 2018 so fixed the
+copyright years.
+
+Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
+Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
+---
+ drivers/i2c/busses/i2c-qup.c | 13 ++-----------
+ 1 file changed, 2 insertions(+), 11 deletions(-)
+
+--- a/drivers/i2c/busses/i2c-qup.c
++++ b/drivers/i2c/busses/i2c-qup.c
+@@ -1,17 +1,8 @@
++// SPDX-License-Identifier: GPL-2.0
+ /*
+- * Copyright (c) 2009-2013, The Linux Foundation. All rights reserved.
++ * Copyright (c) 2009-2013, 2016-2018, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2014, Sony Mobile Communications AB.
+ *
+- *
+- * This program is free software; you can redistribute it and/or modify
+- * it under the terms of the GNU General Public License version 2 and
+- * only version 2 as published by the Free Software Foundation.
+- *
+- * This program is distributed in the hope that it will be useful,
+- * but WITHOUT ANY WARRANTY; without even the implied warranty of
+- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+- * GNU General Public License for more details.
+- *
+ */
+
+ #include <linux/acpi.h>
--- /dev/null
+From 7239872fb3400b21a8f5547257f9f86455867bd6 Mon Sep 17 00:00:00 2001
+From: Abhishek Sahu <absahu@codeaurora.org>
+Date: Mon, 12 Mar 2018 18:44:51 +0530
+Subject: [PATCH 02/13] i2c: qup: fixed releasing dma without flush operation
+ completion
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+The QUP BSLP BAM generates the following error sometimes if the
+current I2C DMA transfer fails and the flush operation has been
+scheduled
+
+ “bam-dma-engine 7884000.dma: Cannot free busy channel”
+
+If any I2C error comes during BAM DMA transfer, then the QUP I2C
+interrupt will be generated and the flush operation will be
+carried out to make I2C consume all scheduled DMA transfer.
+Currently, the same completion structure is being used for BAM
+transfer which has already completed without reinit. It will make
+flush operation wait_for_completion_timeout completed immediately
+and will proceed for freeing the DMA resources where the
+descriptors are still in process.
+
+Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
+Acked-by: Sricharan R <sricharan@codeaurora.org>
+Reviewed-by: Austin Christ <austinwc@codeaurora.org>
+Reviewed-by: Andy Gross <andy.gross@linaro.org>
+Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
+---
+ drivers/i2c/busses/i2c-qup.c | 2 ++
+ 1 file changed, 2 insertions(+)
+
+--- a/drivers/i2c/busses/i2c-qup.c
++++ b/drivers/i2c/busses/i2c-qup.c
+@@ -835,6 +835,8 @@ static int qup_i2c_bam_do_xfer(struct qu
+ }
+
+ if (ret || qup->bus_err || qup->qup_err) {
++ reinit_completion(&qup->xfer);
++
+ if (qup_i2c_change_state(qup, QUP_RUN_STATE)) {
+ dev_err(qup->dev, "change to run state timed out");
+ goto desc_err;
--- /dev/null
+From eb422b539c1f39faf576826b54be93e84d9cb32a Mon Sep 17 00:00:00 2001
+From: Abhishek Sahu <absahu@codeaurora.org>
+Date: Mon, 12 Mar 2018 18:44:52 +0530
+Subject: [PATCH 03/13] i2c: qup: minor code reorganization for use_dma
+
+1. Assigns use_dma in qup_dev structure itself which will
+ help in subsequent patches to determine the mode in IRQ handler.
+2. Does minor code reorganization for loops to reduce the
+ unnecessary comparison and assignment.
+
+Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
+Reviewed-by: Austin Christ <austinwc@codeaurora.org>
+Reviewed-by: Andy Gross <andy.gross@linaro.org>
+Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
+---
+ drivers/i2c/busses/i2c-qup.c | 19 +++++++++++--------
+ 1 file changed, 11 insertions(+), 8 deletions(-)
+
+--- a/drivers/i2c/busses/i2c-qup.c
++++ b/drivers/i2c/busses/i2c-qup.c
+@@ -181,6 +181,8 @@ struct qup_i2c_dev {
+
+ /* dma parameters */
+ bool is_dma;
++ /* To check if the current transfer is using DMA */
++ bool use_dma;
+ struct dma_pool *dpool;
+ struct qup_i2c_tag start_tag;
+ struct qup_i2c_bam brx;
+@@ -1288,7 +1290,7 @@ static int qup_i2c_xfer_v2(struct i2c_ad
+ int num)
+ {
+ struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
+- int ret, len, idx = 0, use_dma = 0;
++ int ret, len, idx = 0;
+
+ qup->bus_err = 0;
+ qup->qup_err = 0;
+@@ -1317,13 +1319,12 @@ static int qup_i2c_xfer_v2(struct i2c_ad
+ len = (msgs[idx].len > qup->out_fifo_sz) ||
+ (msgs[idx].len > qup->in_fifo_sz);
+
+- if ((!is_vmalloc_addr(msgs[idx].buf)) && len) {
+- use_dma = 1;
+- } else {
+- use_dma = 0;
++ if (is_vmalloc_addr(msgs[idx].buf) || !len)
+ break;
+- }
+ }
++
++ if (idx == num)
++ qup->use_dma = true;
+ }
+
+ idx = 0;
+@@ -1347,15 +1348,17 @@ static int qup_i2c_xfer_v2(struct i2c_ad
+
+ reinit_completion(&qup->xfer);
+
+- if (use_dma) {
++ if (qup->use_dma) {
+ ret = qup_i2c_bam_xfer(adap, &msgs[idx], num);
++ qup->use_dma = false;
++ break;
+ } else {
+ if (msgs[idx].flags & I2C_M_RD)
+ ret = qup_i2c_read_one_v2(qup, &msgs[idx]);
+ else
+ ret = qup_i2c_write_one_v2(qup, &msgs[idx]);
+ }
+- } while ((idx++ < (num - 1)) && !use_dma && !ret);
++ } while ((idx++ < (num - 1)) && !ret);
+
+ if (!ret)
+ ret = qup_i2c_change_state(qup, QUP_RESET_STATE);
--- /dev/null
+From 6d5f37f166bb07b04b4d42e9d1f5427b7931cd3c Mon Sep 17 00:00:00 2001
+From: Abhishek Sahu <absahu@codeaurora.org>
+Date: Mon, 12 Mar 2018 18:44:53 +0530
+Subject: [PATCH 04/13] i2c: qup: remove redundant variables for BAM SG count
+
+The rx_nents and tx_nents are redundant. rx_buf and tx_buf can
+be used for total number of SG entries. Since rx_buf and tx_buf
+give the impression that it is buffer instead of count so rename
+it to tx_cnt and rx_cnt for giving it more meaningful variable
+name.
+
+Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
+Reviewed-by: Austin Christ <austinwc@codeaurora.org>
+Reviewed-by: Andy Gross <andy.gross@linaro.org>
+Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
+---
+ drivers/i2c/busses/i2c-qup.c | 42 ++++++++++++++++--------------------
+ 1 file changed, 18 insertions(+), 24 deletions(-)
+
+--- a/drivers/i2c/busses/i2c-qup.c
++++ b/drivers/i2c/busses/i2c-qup.c
+@@ -683,8 +683,8 @@ static int qup_i2c_bam_do_xfer(struct qu
+ struct dma_async_tx_descriptor *txd, *rxd = NULL;
+ int ret = 0, idx = 0, limit = QUP_READ_LIMIT;
+ dma_cookie_t cookie_rx, cookie_tx;
+- u32 rx_nents = 0, tx_nents = 0, len, blocks, rem;
+- u32 i, tlen, tx_len, tx_buf = 0, rx_buf = 0, off = 0;
++ u32 len, blocks, rem;
++ u32 i, tlen, tx_len, tx_cnt = 0, rx_cnt = 0, off = 0;
+ u8 *tags;
+
+ while (idx < num) {
+@@ -698,9 +698,6 @@ static int qup_i2c_bam_do_xfer(struct qu
+ rem = msg->len - (blocks - 1) * limit;
+
+ if (msg->flags & I2C_M_RD) {
+- rx_nents += (blocks * 2) + 1;
+- tx_nents += 1;
+-
+ while (qup->blk.pos < blocks) {
+ tlen = (i == (blocks - 1)) ? rem : limit;
+ tags = &qup->start_tag.start[off + len];
+@@ -708,14 +705,14 @@ static int qup_i2c_bam_do_xfer(struct qu
+ qup->blk.data_len -= tlen;
+
+ /* scratch buf to read the start and len tags */
+- ret = qup_sg_set_buf(&qup->brx.sg[rx_buf++],
++ ret = qup_sg_set_buf(&qup->brx.sg[rx_cnt++],
+ &qup->brx.tag.start[0],
+ 2, qup, DMA_FROM_DEVICE);
+
+ if (ret)
+ return ret;
+
+- ret = qup_sg_set_buf(&qup->brx.sg[rx_buf++],
++ ret = qup_sg_set_buf(&qup->brx.sg[rx_cnt++],
+ &msg->buf[limit * i],
+ tlen, qup,
+ DMA_FROM_DEVICE);
+@@ -725,7 +722,7 @@ static int qup_i2c_bam_do_xfer(struct qu
+ i++;
+ qup->blk.pos = i;
+ }
+- ret = qup_sg_set_buf(&qup->btx.sg[tx_buf++],
++ ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++],
+ &qup->start_tag.start[off],
+ len, qup, DMA_TO_DEVICE);
+ if (ret)
+@@ -733,28 +730,26 @@ static int qup_i2c_bam_do_xfer(struct qu
+
+ off += len;
+ /* scratch buf to read the BAM EOT and FLUSH tags */
+- ret = qup_sg_set_buf(&qup->brx.sg[rx_buf++],
++ ret = qup_sg_set_buf(&qup->brx.sg[rx_cnt++],
+ &qup->brx.tag.start[0],
+ 2, qup, DMA_FROM_DEVICE);
+ if (ret)
+ return ret;
+ } else {
+- tx_nents += (blocks * 2);
+-
+ while (qup->blk.pos < blocks) {
+ tlen = (i == (blocks - 1)) ? rem : limit;
+ tags = &qup->start_tag.start[off + tx_len];
+ len = qup_i2c_set_tags(tags, qup, msg, 1);
+ qup->blk.data_len -= tlen;
+
+- ret = qup_sg_set_buf(&qup->btx.sg[tx_buf++],
++ ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++],
+ tags, len,
+ qup, DMA_TO_DEVICE);
+ if (ret)
+ return ret;
+
+ tx_len += len;
+- ret = qup_sg_set_buf(&qup->btx.sg[tx_buf++],
++ ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++],
+ &msg->buf[limit * i],
+ tlen, qup, DMA_TO_DEVICE);
+ if (ret)
+@@ -766,26 +761,25 @@ static int qup_i2c_bam_do_xfer(struct qu
+
+ if (idx == (num - 1)) {
+ len = 1;
+- if (rx_nents) {
++ if (rx_cnt) {
+ qup->btx.tag.start[0] =
+ QUP_BAM_INPUT_EOT;
+ len++;
+ }
+ qup->btx.tag.start[len - 1] =
+ QUP_BAM_FLUSH_STOP;
+- ret = qup_sg_set_buf(&qup->btx.sg[tx_buf++],
++ ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++],
+ &qup->btx.tag.start[0],
+ len, qup, DMA_TO_DEVICE);
+ if (ret)
+ return ret;
+- tx_nents += 1;
+ }
+ }
+ idx++;
+ msg++;
+ }
+
+- txd = dmaengine_prep_slave_sg(qup->btx.dma, qup->btx.sg, tx_nents,
++ txd = dmaengine_prep_slave_sg(qup->btx.dma, qup->btx.sg, tx_cnt,
+ DMA_MEM_TO_DEV,
+ DMA_PREP_INTERRUPT | DMA_PREP_FENCE);
+ if (!txd) {
+@@ -794,7 +788,7 @@ static int qup_i2c_bam_do_xfer(struct qu
+ goto desc_err;
+ }
+
+- if (!rx_nents) {
++ if (!rx_cnt) {
+ txd->callback = qup_i2c_bam_cb;
+ txd->callback_param = qup;
+ }
+@@ -807,9 +801,9 @@ static int qup_i2c_bam_do_xfer(struct qu
+
+ dma_async_issue_pending(qup->btx.dma);
+
+- if (rx_nents) {
++ if (rx_cnt) {
+ rxd = dmaengine_prep_slave_sg(qup->brx.dma, qup->brx.sg,
+- rx_nents, DMA_DEV_TO_MEM,
++ rx_cnt, DMA_DEV_TO_MEM,
+ DMA_PREP_INTERRUPT);
+ if (!rxd) {
+ dev_err(qup->dev, "failed to get rx desc\n");
+@@ -844,7 +838,7 @@ static int qup_i2c_bam_do_xfer(struct qu
+ goto desc_err;
+ }
+
+- if (rx_nents)
++ if (rx_cnt)
+ writel(QUP_BAM_INPUT_EOT,
+ qup->base + QUP_OUT_FIFO_BASE);
+
+@@ -862,10 +856,10 @@ static int qup_i2c_bam_do_xfer(struct qu
+ }
+
+ desc_err:
+- dma_unmap_sg(qup->dev, qup->btx.sg, tx_nents, DMA_TO_DEVICE);
++ dma_unmap_sg(qup->dev, qup->btx.sg, tx_cnt, DMA_TO_DEVICE);
+
+- if (rx_nents)
+- dma_unmap_sg(qup->dev, qup->brx.sg, rx_nents,
++ if (rx_cnt)
++ dma_unmap_sg(qup->dev, qup->brx.sg, rx_cnt,
+ DMA_FROM_DEVICE);
+
+ return ret;
--- /dev/null
+From c5adc0fa63a930e3313c74bb7c1d4d158130eb41 Mon Sep 17 00:00:00 2001
+From: Abhishek Sahu <absahu@codeaurora.org>
+Date: Mon, 12 Mar 2018 18:44:54 +0530
+Subject: [PATCH 05/13] i2c: qup: schedule EOT and FLUSH tags at the end of
+ transfer
+
+The role of FLUSH and EOT tag is to flush already scheduled
+descriptors in BAM HW in case of error. EOT is required only
+when descriptors are scheduled in RX FIFO. If all the messages
+are WRITE, then only FLUSH tag will be used.
+
+A single BAM transfer can have multiple read and write messages.
+The EOT and FLUSH tags should be scheduled at the end of BAM HW
+descriptors. Since the READ and WRITE can be present in any order
+so for some of the cases, these tags are not being written
+correctly.
+
+Following is one of the example
+
+ READ, READ, READ, READ
+
+Currently EOT and FLUSH tags are being written after each READ.
+If QUP gets NACK for first READ itself, then flush will be
+triggered. It will look for first FLUSH tag in TX FIFO and will
+stop there so only descriptors for first READ descriptors be
+flushed. All the scheduled descriptors should be cleared to
+generate BAM DMA completion.
+
+Now this patch is scheduling FLUSH and EOT only once after all the
+descriptors. So, flush will clear all the scheduled descriptors and
+BAM will generate the completion interrupt.
+
+Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
+Reviewed-by: Sricharan R <sricharan@codeaurora.org>
+Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
+---
+ drivers/i2c/busses/i2c-qup.c | 39 ++++++++++++++++++++++--------------
+ 1 file changed, 24 insertions(+), 15 deletions(-)
+
+--- a/drivers/i2c/busses/i2c-qup.c
++++ b/drivers/i2c/busses/i2c-qup.c
+@@ -551,7 +551,7 @@ static int qup_i2c_set_tags_smb(u16 addr
+ }
+
+ static int qup_i2c_set_tags(u8 *tags, struct qup_i2c_dev *qup,
+- struct i2c_msg *msg, int is_dma)
++ struct i2c_msg *msg)
+ {
+ u16 addr = i2c_8bit_addr_from_msg(msg);
+ int len = 0;
+@@ -592,11 +592,6 @@ static int qup_i2c_set_tags(u8 *tags, st
+ else
+ tags[len++] = data_len;
+
+- if ((msg->flags & I2C_M_RD) && last && is_dma) {
+- tags[len++] = QUP_BAM_INPUT_EOT;
+- tags[len++] = QUP_BAM_FLUSH_STOP;
+- }
+-
+ return len;
+ }
+
+@@ -605,7 +600,7 @@ static int qup_i2c_issue_xfer_v2(struct
+ int data_len = 0, tag_len, index;
+ int ret;
+
+- tag_len = qup_i2c_set_tags(qup->blk.tags, qup, msg, 0);
++ tag_len = qup_i2c_set_tags(qup->blk.tags, qup, msg);
+ index = msg->len - qup->blk.data_len;
+
+ /* only tags are written for read */
+@@ -701,7 +696,7 @@ static int qup_i2c_bam_do_xfer(struct qu
+ while (qup->blk.pos < blocks) {
+ tlen = (i == (blocks - 1)) ? rem : limit;
+ tags = &qup->start_tag.start[off + len];
+- len += qup_i2c_set_tags(tags, qup, msg, 1);
++ len += qup_i2c_set_tags(tags, qup, msg);
+ qup->blk.data_len -= tlen;
+
+ /* scratch buf to read the start and len tags */
+@@ -729,17 +724,11 @@ static int qup_i2c_bam_do_xfer(struct qu
+ return ret;
+
+ off += len;
+- /* scratch buf to read the BAM EOT and FLUSH tags */
+- ret = qup_sg_set_buf(&qup->brx.sg[rx_cnt++],
+- &qup->brx.tag.start[0],
+- 2, qup, DMA_FROM_DEVICE);
+- if (ret)
+- return ret;
+ } else {
+ while (qup->blk.pos < blocks) {
+ tlen = (i == (blocks - 1)) ? rem : limit;
+ tags = &qup->start_tag.start[off + tx_len];
+- len = qup_i2c_set_tags(tags, qup, msg, 1);
++ len = qup_i2c_set_tags(tags, qup, msg);
+ qup->blk.data_len -= tlen;
+
+ ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++],
+@@ -779,6 +768,26 @@ static int qup_i2c_bam_do_xfer(struct qu
+ msg++;
+ }
+
++ /* schedule the EOT and FLUSH I2C tags */
++ len = 1;
++ if (rx_cnt) {
++ qup->btx.tag.start[0] = QUP_BAM_INPUT_EOT;
++ len++;
++
++ /* scratch buf to read the BAM EOT and FLUSH tags */
++ ret = qup_sg_set_buf(&qup->brx.sg[rx_cnt++],
++ &qup->brx.tag.start[0],
++ 2, qup, DMA_FROM_DEVICE);
++ if (ret)
++ return ret;
++ }
++
++ qup->btx.tag.start[len - 1] = QUP_BAM_FLUSH_STOP;
++ ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++], &qup->btx.tag.start[0],
++ len, qup, DMA_TO_DEVICE);
++ if (ret)
++ return ret;
++
+ txd = dmaengine_prep_slave_sg(qup->btx.dma, qup->btx.sg, tx_cnt,
+ DMA_MEM_TO_DEV,
+ DMA_PREP_INTERRUPT | DMA_PREP_FENCE);
--- /dev/null
+From 7e6c35fe602df6821b3e7db5b1ba656162750fda Mon Sep 17 00:00:00 2001
+From: Abhishek Sahu <absahu@codeaurora.org>
+Date: Mon, 12 Mar 2018 18:44:55 +0530
+Subject: [PATCH 06/13] i2c: qup: fix the transfer length for BAM RX EOT FLUSH
+ tags
+
+In case of FLUSH operation, BAM copies INPUT EOT FLUSH (0x94)
+instead of normal EOT (0x93) tag in input data stream when an
+input EOT tag is received during flush operation. So only one tag
+will be written instead of 2 separate tags.
+
+Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
+Reviewed-by: Andy Gross <andy.gross@linaro.org>
+Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
+---
+ drivers/i2c/busses/i2c-qup.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+--- a/drivers/i2c/busses/i2c-qup.c
++++ b/drivers/i2c/busses/i2c-qup.c
+@@ -774,10 +774,10 @@ static int qup_i2c_bam_do_xfer(struct qu
+ qup->btx.tag.start[0] = QUP_BAM_INPUT_EOT;
+ len++;
+
+- /* scratch buf to read the BAM EOT and FLUSH tags */
++ /* scratch buf to read the BAM EOT FLUSH tags */
+ ret = qup_sg_set_buf(&qup->brx.sg[rx_cnt++],
+ &qup->brx.tag.start[0],
+- 2, qup, DMA_FROM_DEVICE);
++ 1, qup, DMA_FROM_DEVICE);
+ if (ret)
+ return ret;
+ }
--- /dev/null
+From 3f450d3eea14799b14192231840c1753a660f150 Mon Sep 17 00:00:00 2001
+From: Abhishek Sahu <absahu@codeaurora.org>
+Date: Mon, 12 Mar 2018 18:44:56 +0530
+Subject: [PATCH 07/13] i2c: qup: proper error handling for i2c error in BAM
+ mode
+
+Currently the i2c error handling in BAM mode is not working
+properly in stress condition.
+
+1. After an error, the FIFO are being written with FLUSH and
+ EOT tags which should not be required since already these tags
+ have been written in BAM descriptor itself.
+
+2. QUP state is being moved to RESET in IRQ handler in case
+ of error. When QUP HW encounters an error in BAM mode then it
+ moves the QUP STATE to PAUSE state. In this case, I2C_FLUSH
+ command needs to be executed while moving to RUN_STATE by writing
+ to the QUP_STATE register with the I2C_FLUSH bit set to 1.
+
+3. In Error case, sometimes, QUP generates more than one
+ interrupt which will trigger the complete again. After an error,
+ the flush operation will be scheduled after doing
+ reinit_completion which should be triggered by BAM IRQ callback.
+ If the second QUP IRQ comes during this time then it will call
+ the complete and the transfer function will assume the all the
+ BAM HW descriptors have been completed.
+
+4. The release DMA is being called after each error which
+ will free the DMA tx and rx channels. The error like NACK is very
+ common in I2C transfer and every time this will be overhead. Now,
+ since the error handling is proper so this release channel can be
+ completely avoided.
+
+Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
+Reviewed-by: Sricharan R <sricharan@codeaurora.org>
+Reviewed-by: Austin Christ <austinwc@codeaurora.org>
+Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
+---
+ drivers/i2c/busses/i2c-qup.c | 25 ++++++++++++++++---------
+ 1 file changed, 16 insertions(+), 9 deletions(-)
+
+--- a/drivers/i2c/busses/i2c-qup.c
++++ b/drivers/i2c/busses/i2c-qup.c
+@@ -219,9 +219,24 @@ static irqreturn_t qup_i2c_interrupt(int
+ if (bus_err)
+ writel(bus_err, qup->base + QUP_I2C_STATUS);
+
++ /*
++ * Check for BAM mode and returns if already error has come for current
++ * transfer. In Error case, sometimes, QUP generates more than one
++ * interrupt.
++ */
++ if (qup->use_dma && (qup->qup_err || qup->bus_err))
++ return IRQ_HANDLED;
++
+ /* Reset the QUP State in case of error */
+ if (qup_err || bus_err) {
+- writel(QUP_RESET_STATE, qup->base + QUP_STATE);
++ /*
++ * Don’t reset the QUP state in case of BAM mode. The BAM
++ * flush operation needs to be scheduled in transfer function
++ * which will clear the remaining schedule descriptors in BAM
++ * HW FIFO and generates the BAM interrupt.
++ */
++ if (!qup->use_dma)
++ writel(QUP_RESET_STATE, qup->base + QUP_STATE);
+ goto done;
+ }
+
+@@ -847,20 +862,12 @@ static int qup_i2c_bam_do_xfer(struct qu
+ goto desc_err;
+ }
+
+- if (rx_cnt)
+- writel(QUP_BAM_INPUT_EOT,
+- qup->base + QUP_OUT_FIFO_BASE);
+-
+- writel(QUP_BAM_FLUSH_STOP, qup->base + QUP_OUT_FIFO_BASE);
+-
+ qup_i2c_flush(qup);
+
+ /* wait for remaining interrupts to occur */
+ if (!wait_for_completion_timeout(&qup->xfer, HZ))
+ dev_err(qup->dev, "flush timed out\n");
+
+- qup_i2c_rel_dma(qup);
+-
+ ret = (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO;
+ }
+
--- /dev/null
+From 08f15963bc751bc818294c0f75a9aaca299c4052 Mon Sep 17 00:00:00 2001
+From: Abhishek Sahu <absahu@codeaurora.org>
+Date: Mon, 12 Mar 2018 18:44:57 +0530
+Subject: [PATCH 08/13] i2c: qup: use the complete transfer length to choose
+ DMA mode
+
+Currently each message length in complete transfer is being
+checked for determining DMA mode and if any of the message length
+is less than FIFO length then non DMA mode is being used which
+will increase overhead. DMA can be used for any length and it
+should be determined with complete transfer length. Now, this
+patch selects DMA mode if the total length is greater than FIFO
+length.
+
+Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
+Reviewed-by: Austin Christ <austinwc@codeaurora.org>
+Reviewed-by: Andy Gross <andy.gross@linaro.org>
+Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
+---
+ drivers/i2c/busses/i2c-qup.c | 13 +++++++------
+ 1 file changed, 7 insertions(+), 6 deletions(-)
+
+--- a/drivers/i2c/busses/i2c-qup.c
++++ b/drivers/i2c/busses/i2c-qup.c
+@@ -1300,7 +1300,8 @@ static int qup_i2c_xfer_v2(struct i2c_ad
+ int num)
+ {
+ struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
+- int ret, len, idx = 0;
++ int ret, idx = 0;
++ unsigned int total_len = 0;
+
+ qup->bus_err = 0;
+ qup->qup_err = 0;
+@@ -1326,14 +1327,14 @@ static int qup_i2c_xfer_v2(struct i2c_ad
+ goto out;
+ }
+
+- len = (msgs[idx].len > qup->out_fifo_sz) ||
+- (msgs[idx].len > qup->in_fifo_sz);
+-
+- if (is_vmalloc_addr(msgs[idx].buf) || !len)
++ if (is_vmalloc_addr(msgs[idx].buf))
+ break;
++
++ total_len += msgs[idx].len;
+ }
+
+- if (idx == num)
++ if (idx == num && (total_len > qup->out_fifo_sz ||
++ total_len > qup->in_fifo_sz))
+ qup->use_dma = true;
+ }
+
--- /dev/null
+From ecb6e1e5f4352055a5761b945a833a925d51bf8d Mon Sep 17 00:00:00 2001
+From: Abhishek Sahu <absahu@codeaurora.org>
+Date: Mon, 12 Mar 2018 18:44:58 +0530
+Subject: [PATCH 09/13] i2c: qup: change completion timeout according to
+ transfer length
+
+Currently the completion timeout is being taken according to
+maximum transfer length which is too high if SCL is operating in
+high frequency. This patch calculates timeout on the basis of
+one-byte transfer time and uses the same for completion timeout.
+
+Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
+Reviewed-by: Andy Gross <andy.gross@linaro.org>
+Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
+---
+ drivers/i2c/busses/i2c-qup.c | 13 ++++++++++---
+ 1 file changed, 10 insertions(+), 3 deletions(-)
+
+--- a/drivers/i2c/busses/i2c-qup.c
++++ b/drivers/i2c/busses/i2c-qup.c
+@@ -121,8 +121,12 @@
+ #define MX_TX_RX_LEN SZ_64K
+ #define MX_BLOCKS (MX_TX_RX_LEN / QUP_READ_LIMIT)
+
+-/* Max timeout in ms for 32k bytes */
+-#define TOUT_MAX 300
++/*
++ * Minimum transfer timeout for i2c transfers in seconds. It will be added on
++ * the top of maximum transfer time calculated from i2c bus speed to compensate
++ * the overheads.
++ */
++#define TOUT_MIN 2
+
+ /* Default values. Use these if FW query fails */
+ #define DEFAULT_CLK_FREQ 100000
+@@ -163,6 +167,7 @@ struct qup_i2c_dev {
+ int in_blk_sz;
+
+ unsigned long one_byte_t;
++ unsigned long xfer_timeout;
+ struct qup_i2c_block blk;
+
+ struct i2c_msg *msg;
+@@ -849,7 +854,7 @@ static int qup_i2c_bam_do_xfer(struct qu
+ dma_async_issue_pending(qup->brx.dma);
+ }
+
+- if (!wait_for_completion_timeout(&qup->xfer, TOUT_MAX * HZ)) {
++ if (!wait_for_completion_timeout(&qup->xfer, qup->xfer_timeout)) {
+ dev_err(qup->dev, "normal trans timed out\n");
+ ret = -ETIMEDOUT;
+ }
+@@ -1605,6 +1610,8 @@ nodma:
+ */
+ one_bit_t = (USEC_PER_SEC / clk_freq) + 1;
+ qup->one_byte_t = one_bit_t * 9;
++ qup->xfer_timeout = TOUT_MIN * HZ +
++ usecs_to_jiffies(MX_TX_RX_LEN * qup->one_byte_t);
+
+ dev_dbg(qup->dev, "IN:block:%d, fifo:%d, OUT:block:%d, fifo:%d\n",
+ qup->in_blk_sz, qup->in_fifo_sz,
--- /dev/null
+From 6f2f0f6465acbd59391c43352ff0df77df1f01db Mon Sep 17 00:00:00 2001
+From: Abhishek Sahu <absahu@codeaurora.org>
+Date: Mon, 12 Mar 2018 18:44:59 +0530
+Subject: [PATCH 10/13] i2c: qup: fix buffer overflow for multiple msg of
+ maximum xfer len
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+The BAM mode requires buffer for start tag data and tx, rx SG
+list. Currently, this is being taken for maximum transfer length
+(65K). But an I2C transfer can have multiple messages and each
+message can be of this maximum length so the buffer overflow will
+happen in this case. Since increasing buffer length won’t be
+feasible since an I2C transfer can contain any number of messages
+so this patch does following changes to make i2c transfers working
+for multiple messages case.
+
+1. Calculate the required buffers for 2 maximum length messages
+ (65K * 2).
+2. Split the descriptor formation and descriptor scheduling.
+ The idea is to fit as many messages in one DMA transfers for 65K
+ threshold value (max_xfer_sg_len). Whenever the sg_cnt is
+ crossing this, then schedule the BAM transfer and subsequent
+ transfer will again start from zero.
+
+Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
+Reviewed-by: Andy Gross <andy.gross@linaro.org>
+Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
+---
+ drivers/i2c/busses/i2c-qup.c | 194 ++++++++++++++++++++---------------
+ 1 file changed, 110 insertions(+), 84 deletions(-)
+
+--- a/drivers/i2c/busses/i2c-qup.c
++++ b/drivers/i2c/busses/i2c-qup.c
+@@ -118,8 +118,12 @@
+ #define ONE_BYTE 0x1
+ #define QUP_I2C_MX_CONFIG_DURING_RUN BIT(31)
+
++/* Maximum transfer length for single DMA descriptor */
+ #define MX_TX_RX_LEN SZ_64K
+ #define MX_BLOCKS (MX_TX_RX_LEN / QUP_READ_LIMIT)
++/* Maximum transfer length for all DMA descriptors */
++#define MX_DMA_TX_RX_LEN (2 * MX_TX_RX_LEN)
++#define MX_DMA_BLOCKS (MX_DMA_TX_RX_LEN / QUP_READ_LIMIT)
+
+ /*
+ * Minimum transfer timeout for i2c transfers in seconds. It will be added on
+@@ -150,6 +154,7 @@ struct qup_i2c_bam {
+ struct qup_i2c_tag tag;
+ struct dma_chan *dma;
+ struct scatterlist *sg;
++ unsigned int sg_cnt;
+ };
+
+ struct qup_i2c_dev {
+@@ -188,6 +193,8 @@ struct qup_i2c_dev {
+ bool is_dma;
+ /* To check if the current transfer is using DMA */
+ bool use_dma;
++ unsigned int max_xfer_sg_len;
++ unsigned int tag_buf_pos;
+ struct dma_pool *dpool;
+ struct qup_i2c_tag start_tag;
+ struct qup_i2c_bam brx;
+@@ -692,102 +699,87 @@ static int qup_i2c_req_dma(struct qup_i2
+ return 0;
+ }
+
+-static int qup_i2c_bam_do_xfer(struct qup_i2c_dev *qup, struct i2c_msg *msg,
+- int num)
++static int qup_i2c_bam_make_desc(struct qup_i2c_dev *qup, struct i2c_msg *msg)
+ {
+- struct dma_async_tx_descriptor *txd, *rxd = NULL;
+- int ret = 0, idx = 0, limit = QUP_READ_LIMIT;
+- dma_cookie_t cookie_rx, cookie_tx;
+- u32 len, blocks, rem;
+- u32 i, tlen, tx_len, tx_cnt = 0, rx_cnt = 0, off = 0;
++ int ret = 0, limit = QUP_READ_LIMIT;
++ u32 len = 0, blocks, rem;
++ u32 i = 0, tlen, tx_len = 0;
+ u8 *tags;
+
+- while (idx < num) {
+- tx_len = 0, len = 0, i = 0;
+-
+- qup->is_last = (idx == (num - 1));
++ qup_i2c_set_blk_data(qup, msg);
+
+- qup_i2c_set_blk_data(qup, msg);
++ blocks = qup->blk.count;
++ rem = msg->len - (blocks - 1) * limit;
+
+- blocks = qup->blk.count;
+- rem = msg->len - (blocks - 1) * limit;
++ if (msg->flags & I2C_M_RD) {
++ while (qup->blk.pos < blocks) {
++ tlen = (i == (blocks - 1)) ? rem : limit;
++ tags = &qup->start_tag.start[qup->tag_buf_pos + len];
++ len += qup_i2c_set_tags(tags, qup, msg);
++ qup->blk.data_len -= tlen;
++
++ /* scratch buf to read the start and len tags */
++ ret = qup_sg_set_buf(&qup->brx.sg[qup->brx.sg_cnt++],
++ &qup->brx.tag.start[0],
++ 2, qup, DMA_FROM_DEVICE);
+
+- if (msg->flags & I2C_M_RD) {
+- while (qup->blk.pos < blocks) {
+- tlen = (i == (blocks - 1)) ? rem : limit;
+- tags = &qup->start_tag.start[off + len];
+- len += qup_i2c_set_tags(tags, qup, msg);
+- qup->blk.data_len -= tlen;
+-
+- /* scratch buf to read the start and len tags */
+- ret = qup_sg_set_buf(&qup->brx.sg[rx_cnt++],
+- &qup->brx.tag.start[0],
+- 2, qup, DMA_FROM_DEVICE);
+-
+- if (ret)
+- return ret;
+-
+- ret = qup_sg_set_buf(&qup->brx.sg[rx_cnt++],
+- &msg->buf[limit * i],
+- tlen, qup,
+- DMA_FROM_DEVICE);
+- if (ret)
+- return ret;
++ if (ret)
++ return ret;
+
+- i++;
+- qup->blk.pos = i;
+- }
+- ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++],
+- &qup->start_tag.start[off],
+- len, qup, DMA_TO_DEVICE);
++ ret = qup_sg_set_buf(&qup->brx.sg[qup->brx.sg_cnt++],
++ &msg->buf[limit * i],
++ tlen, qup,
++ DMA_FROM_DEVICE);
+ if (ret)
+ return ret;
+
+- off += len;
+- } else {
+- while (qup->blk.pos < blocks) {
+- tlen = (i == (blocks - 1)) ? rem : limit;
+- tags = &qup->start_tag.start[off + tx_len];
+- len = qup_i2c_set_tags(tags, qup, msg);
+- qup->blk.data_len -= tlen;
+-
+- ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++],
+- tags, len,
+- qup, DMA_TO_DEVICE);
+- if (ret)
+- return ret;
+-
+- tx_len += len;
+- ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++],
+- &msg->buf[limit * i],
+- tlen, qup, DMA_TO_DEVICE);
+- if (ret)
+- return ret;
+- i++;
+- qup->blk.pos = i;
+- }
+- off += tx_len;
++ i++;
++ qup->blk.pos = i;
++ }
++ ret = qup_sg_set_buf(&qup->btx.sg[qup->btx.sg_cnt++],
++ &qup->start_tag.start[qup->tag_buf_pos],
++ len, qup, DMA_TO_DEVICE);
++ if (ret)
++ return ret;
+
+- if (idx == (num - 1)) {
+- len = 1;
+- if (rx_cnt) {
+- qup->btx.tag.start[0] =
+- QUP_BAM_INPUT_EOT;
+- len++;
+- }
+- qup->btx.tag.start[len - 1] =
+- QUP_BAM_FLUSH_STOP;
+- ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++],
+- &qup->btx.tag.start[0],
+- len, qup, DMA_TO_DEVICE);
+- if (ret)
+- return ret;
+- }
++ qup->tag_buf_pos += len;
++ } else {
++ while (qup->blk.pos < blocks) {
++ tlen = (i == (blocks - 1)) ? rem : limit;
++ tags = &qup->start_tag.start[qup->tag_buf_pos + tx_len];
++ len = qup_i2c_set_tags(tags, qup, msg);
++ qup->blk.data_len -= tlen;
++
++ ret = qup_sg_set_buf(&qup->btx.sg[qup->btx.sg_cnt++],
++ tags, len,
++ qup, DMA_TO_DEVICE);
++ if (ret)
++ return ret;
++
++ tx_len += len;
++ ret = qup_sg_set_buf(&qup->btx.sg[qup->btx.sg_cnt++],
++ &msg->buf[limit * i],
++ tlen, qup, DMA_TO_DEVICE);
++ if (ret)
++ return ret;
++ i++;
++ qup->blk.pos = i;
+ }
+- idx++;
+- msg++;
++
++ qup->tag_buf_pos += tx_len;
+ }
+
++ return 0;
++}
++
++static int qup_i2c_bam_schedule_desc(struct qup_i2c_dev *qup)
++{
++ struct dma_async_tx_descriptor *txd, *rxd = NULL;
++ int ret = 0;
++ dma_cookie_t cookie_rx, cookie_tx;
++ u32 len = 0;
++ u32 tx_cnt = qup->btx.sg_cnt, rx_cnt = qup->brx.sg_cnt;
++
+ /* schedule the EOT and FLUSH I2C tags */
+ len = 1;
+ if (rx_cnt) {
+@@ -886,11 +878,19 @@ desc_err:
+ return ret;
+ }
+
++static void qup_i2c_bam_clear_tag_buffers(struct qup_i2c_dev *qup)
++{
++ qup->btx.sg_cnt = 0;
++ qup->brx.sg_cnt = 0;
++ qup->tag_buf_pos = 0;
++}
++
+ static int qup_i2c_bam_xfer(struct i2c_adapter *adap, struct i2c_msg *msg,
+ int num)
+ {
+ struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
+ int ret = 0;
++ int idx = 0;
+
+ enable_irq(qup->irq);
+ ret = qup_i2c_req_dma(qup);
+@@ -913,9 +913,34 @@ static int qup_i2c_bam_xfer(struct i2c_a
+ goto out;
+
+ writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
++ qup_i2c_bam_clear_tag_buffers(qup);
++
++ for (idx = 0; idx < num; idx++) {
++ qup->msg = msg + idx;
++ qup->is_last = idx == (num - 1);
++
++ ret = qup_i2c_bam_make_desc(qup, qup->msg);
++ if (ret)
++ break;
++
++ /*
++ * Make DMA descriptor and schedule the BAM transfer if its
++ * already crossed the maximum length. Since the memory for all
++ * tags buffers have been taken for 2 maximum possible
++ * transfers length so it will never cross the buffer actual
++ * length.
++ */
++ if (qup->btx.sg_cnt > qup->max_xfer_sg_len ||
++ qup->brx.sg_cnt > qup->max_xfer_sg_len ||
++ qup->is_last) {
++ ret = qup_i2c_bam_schedule_desc(qup);
++ if (ret)
++ break;
++
++ qup_i2c_bam_clear_tag_buffers(qup);
++ }
++ }
+
+- qup->msg = msg;
+- ret = qup_i2c_bam_do_xfer(qup, qup->msg, num);
+ out:
+ disable_irq(qup->irq);
+
+@@ -1468,7 +1493,8 @@ static int qup_i2c_probe(struct platform
+ else if (ret != 0)
+ goto nodma;
+
+- blocks = (MX_BLOCKS << 1) + 1;
++ qup->max_xfer_sg_len = (MX_BLOCKS << 1);
++ blocks = (MX_DMA_BLOCKS << 1) + 1;
+ qup->btx.sg = devm_kzalloc(&pdev->dev,
+ sizeof(*qup->btx.sg) * blocks,
+ GFP_KERNEL);
+@@ -1611,7 +1637,7 @@ nodma:
+ one_bit_t = (USEC_PER_SEC / clk_freq) + 1;
+ qup->one_byte_t = one_bit_t * 9;
+ qup->xfer_timeout = TOUT_MIN * HZ +
+- usecs_to_jiffies(MX_TX_RX_LEN * qup->one_byte_t);
++ usecs_to_jiffies(MX_DMA_TX_RX_LEN * qup->one_byte_t);
+
+ dev_dbg(qup->dev, "IN:block:%d, fifo:%d, OUT:block:%d, fifo:%d\n",
+ qup->in_blk_sz, qup->in_fifo_sz,
--- /dev/null
+From f7714b4e451bdcb7918b9aad14af22684ceac638 Mon Sep 17 00:00:00 2001
+From: Abhishek Sahu <absahu@codeaurora.org>
+Date: Mon, 12 Mar 2018 18:45:00 +0530
+Subject: [PATCH 11/13] i2c: qup: send NACK for last read sub transfers
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+According to I2c specification, “If a master-receiver sends a
+repeated START condition, it sends a not-acknowledge (A) just
+before the repeated START condition”. QUP v2 supports sending
+of NACK without stop with QUP_TAG_V2_DATARD_NACK so added the
+same.
+
+Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
+Reviewed-by: Austin Christ <austinwc@codeaurora.org>
+Reviewed-by: Andy Gross <andy.gross@linaro.org>
+Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
+---
+ drivers/i2c/busses/i2c-qup.c | 5 ++++-
+ 1 file changed, 4 insertions(+), 1 deletion(-)
+
+--- a/drivers/i2c/busses/i2c-qup.c
++++ b/drivers/i2c/busses/i2c-qup.c
+@@ -104,6 +104,7 @@
+ #define QUP_TAG_V2_DATAWR 0x82
+ #define QUP_TAG_V2_DATAWR_STOP 0x83
+ #define QUP_TAG_V2_DATARD 0x85
++#define QUP_TAG_V2_DATARD_NACK 0x86
+ #define QUP_TAG_V2_DATARD_STOP 0x87
+
+ /* Status, Error flags */
+@@ -606,7 +607,9 @@ static int qup_i2c_set_tags(u8 *tags, st
+ tags[len++] = QUP_TAG_V2_DATAWR_STOP;
+ } else {
+ if (msg->flags & I2C_M_RD)
+- tags[len++] = QUP_TAG_V2_DATARD;
++ tags[len++] = qup->blk.pos == (qup->blk.count - 1) ?
++ QUP_TAG_V2_DATARD_NACK :
++ QUP_TAG_V2_DATARD;
+ else
+ tags[len++] = QUP_TAG_V2_DATAWR;
+ }
--- /dev/null
+From fbfab1ab065879370541caf0e514987368eb41b2 Mon Sep 17 00:00:00 2001
+From: Abhishek Sahu <absahu@codeaurora.org>
+Date: Mon, 12 Mar 2018 18:45:01 +0530
+Subject: [PATCH 12/13] i2c: qup: reorganization of driver code to remove
+ polling for qup v1
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Following are the major issues in current driver code
+
+1. The current driver simply assumes the transfer completion
+ whenever its gets any non-error interrupts and then simply do the
+ polling of available/free bytes in FIFO.
+2. The block mode is not working properly since no handling in
+ being done for OUT_BLOCK_WRITE_REQ and IN_BLOCK_READ_REQ.
+
+Because of above, i2c v1 transfers of size greater than 32 are failing
+with following error message
+
+ i2c_qup 78b6000.i2c: timeout for fifo out full
+
+To make block mode working properly and move to use the interrupts
+instead of polling, major code reorganization is required. Following
+are the major changes done in this patch
+
+1. Remove the polling of TX FIFO free space and RX FIFO available
+ bytes and move to interrupts completely. QUP has QUP_MX_OUTPUT_DONE,
+ QUP_MX_INPUT_DONE, OUT_BLOCK_WRITE_REQ and IN_BLOCK_READ_REQ
+ interrupts to handle FIFO’s properly so check all these interrupts.
+2. During write, For FIFO mode, TX FIFO can be directly written
+ without checking for FIFO space. For block mode, the QUP will generate
+ OUT_BLOCK_WRITE_REQ interrupt whenever it has block size of available
+ space.
+3. During read, both TX and RX FIFO will be used. TX will be used
+ for writing tags and RX will be used for receiving the data. In QUP,
+ TX and RX can operate in separate mode so configure modes accordingly.
+4. For read FIFO mode, wait for QUP_MX_INPUT_DONE interrupt which
+ will be generated after all the bytes have been copied in RX FIFO. For
+ read Block mode, QUP will generate IN_BLOCK_READ_REQ interrupts
+ whenever it has block size of available data.
+
+Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
+Reviewed-by: Sricharan R <sricharan@codeaurora.org>
+Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
+---
+ drivers/i2c/busses/i2c-qup.c | 366 +++++++++++++++++++++--------------
+ 1 file changed, 223 insertions(+), 143 deletions(-)
+
+--- a/drivers/i2c/busses/i2c-qup.c
++++ b/drivers/i2c/busses/i2c-qup.c
+@@ -64,8 +64,11 @@
+ #define QUP_IN_SVC_FLAG BIT(9)
+ #define QUP_MX_OUTPUT_DONE BIT(10)
+ #define QUP_MX_INPUT_DONE BIT(11)
++#define OUT_BLOCK_WRITE_REQ BIT(12)
++#define IN_BLOCK_READ_REQ BIT(13)
+
+ /* I2C mini core related values */
++#define QUP_NO_INPUT BIT(7)
+ #define QUP_CLOCK_AUTO_GATE BIT(13)
+ #define I2C_MINI_CORE (2 << 8)
+ #define I2C_N_VAL 15
+@@ -137,13 +140,36 @@
+ #define DEFAULT_CLK_FREQ 100000
+ #define DEFAULT_SRC_CLK 20000000
+
++/*
++ * count: no of blocks
++ * pos: current block number
++ * tx_tag_len: tx tag length for current block
++ * rx_tag_len: rx tag length for current block
++ * data_len: remaining data length for current message
++ * total_tx_len: total tx length including tag bytes for current QUP transfer
++ * total_rx_len: total rx length including tag bytes for current QUP transfer
++ * tx_fifo_free: number of free bytes in current QUP block write.
++ * fifo_available: number of available bytes in RX FIFO for current
++ * QUP block read
++ * rx_bytes_read: if all the bytes have been read from rx FIFO.
++ * is_tx_blk_mode: whether tx uses block or FIFO mode in case of non BAM xfer.
++ * is_rx_blk_mode: whether rx uses block or FIFO mode in case of non BAM xfer.
++ * tags: contains tx tag bytes for current QUP transfer
++ */
+ struct qup_i2c_block {
+- int count;
+- int pos;
+- int tx_tag_len;
+- int rx_tag_len;
+- int data_len;
+- u8 tags[6];
++ int count;
++ int pos;
++ int tx_tag_len;
++ int rx_tag_len;
++ int data_len;
++ int total_tx_len;
++ int total_rx_len;
++ int tx_fifo_free;
++ int fifo_available;
++ bool rx_bytes_read;
++ bool is_tx_blk_mode;
++ bool is_rx_blk_mode;
++ u8 tags[6];
+ };
+
+ struct qup_i2c_tag {
+@@ -186,6 +212,7 @@ struct qup_i2c_dev {
+
+ /* To check if this is the last msg */
+ bool is_last;
++ bool is_qup_v1;
+
+ /* To configure when bus is in run state */
+ int config_run;
+@@ -202,11 +229,18 @@ struct qup_i2c_dev {
+ struct qup_i2c_bam btx;
+
+ struct completion xfer;
++ /* function to write data in tx fifo */
++ void (*write_tx_fifo)(struct qup_i2c_dev *qup);
++ /* function to read data from rx fifo */
++ void (*read_rx_fifo)(struct qup_i2c_dev *qup);
++ /* function to write tags in tx fifo for i2c read transfer */
++ void (*write_rx_tags)(struct qup_i2c_dev *qup);
+ };
+
+ static irqreturn_t qup_i2c_interrupt(int irq, void *dev)
+ {
+ struct qup_i2c_dev *qup = dev;
++ struct qup_i2c_block *blk = &qup->blk;
+ u32 bus_err;
+ u32 qup_err;
+ u32 opflags;
+@@ -253,12 +287,48 @@ static irqreturn_t qup_i2c_interrupt(int
+ goto done;
+ }
+
+- if (opflags & QUP_IN_SVC_FLAG)
+- writel(QUP_IN_SVC_FLAG, qup->base + QUP_OPERATIONAL);
++ if (!qup->is_qup_v1)
++ goto done;
+
+- if (opflags & QUP_OUT_SVC_FLAG)
++ if (opflags & QUP_OUT_SVC_FLAG) {
+ writel(QUP_OUT_SVC_FLAG, qup->base + QUP_OPERATIONAL);
+
++ if (opflags & OUT_BLOCK_WRITE_REQ) {
++ blk->tx_fifo_free += qup->out_blk_sz;
++ if (qup->msg->flags & I2C_M_RD)
++ qup->write_rx_tags(qup);
++ else
++ qup->write_tx_fifo(qup);
++ }
++ }
++
++ if (opflags & QUP_IN_SVC_FLAG) {
++ writel(QUP_IN_SVC_FLAG, qup->base + QUP_OPERATIONAL);
++
++ if (!blk->is_rx_blk_mode) {
++ blk->fifo_available += qup->in_fifo_sz;
++ qup->read_rx_fifo(qup);
++ } else if (opflags & IN_BLOCK_READ_REQ) {
++ blk->fifo_available += qup->in_blk_sz;
++ qup->read_rx_fifo(qup);
++ }
++ }
++
++ if (qup->msg->flags & I2C_M_RD) {
++ if (!blk->rx_bytes_read)
++ return IRQ_HANDLED;
++ } else {
++ /*
++ * Ideally, QUP_MAX_OUTPUT_DONE_FLAG should be checked
++ * for FIFO mode also. But, QUP_MAX_OUTPUT_DONE_FLAG lags
++ * behind QUP_OUTPUT_SERVICE_FLAG sometimes. The only reason
++ * of interrupt for write message in FIFO mode is
++ * QUP_MAX_OUTPUT_DONE_FLAG condition.
++ */
++ if (blk->is_tx_blk_mode && !(opflags & QUP_MX_OUTPUT_DONE))
++ return IRQ_HANDLED;
++ }
++
+ done:
+ qup->qup_err = qup_err;
+ qup->bus_err = bus_err;
+@@ -324,6 +394,28 @@ static int qup_i2c_change_state(struct q
+ return 0;
+ }
+
++/* Check if I2C bus returns to IDLE state */
++static int qup_i2c_bus_active(struct qup_i2c_dev *qup, int len)
++{
++ unsigned long timeout;
++ u32 status;
++ int ret = 0;
++
++ timeout = jiffies + len * 4;
++ for (;;) {
++ status = readl(qup->base + QUP_I2C_STATUS);
++ if (!(status & I2C_STATUS_BUS_ACTIVE))
++ break;
++
++ if (time_after(jiffies, timeout))
++ ret = -ETIMEDOUT;
++
++ usleep_range(len, len * 2);
++ }
++
++ return ret;
++}
++
+ /**
+ * qup_i2c_wait_ready - wait for a give number of bytes in tx/rx path
+ * @qup: The qup_i2c_dev device
+@@ -394,23 +486,6 @@ static void qup_i2c_set_write_mode_v2(st
+ }
+ }
+
+-static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg)
+-{
+- /* Number of entries to shift out, including the start */
+- int total = msg->len + 1;
+-
+- if (total < qup->out_fifo_sz) {
+- /* FIFO mode */
+- writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE);
+- writel(total, qup->base + QUP_MX_WRITE_CNT);
+- } else {
+- /* BLOCK mode (transfer data on chunks) */
+- writel(QUP_OUTPUT_BLK_MODE | QUP_REPACK_EN,
+- qup->base + QUP_IO_MODE);
+- writel(total, qup->base + QUP_MX_OUTPUT_CNT);
+- }
+-}
+-
+ static int check_for_fifo_space(struct qup_i2c_dev *qup)
+ {
+ int ret;
+@@ -443,28 +518,25 @@ out:
+ return ret;
+ }
+
+-static int qup_i2c_issue_write(struct qup_i2c_dev *qup, struct i2c_msg *msg)
++static void qup_i2c_write_tx_fifo_v1(struct qup_i2c_dev *qup)
+ {
++ struct qup_i2c_block *blk = &qup->blk;
++ struct i2c_msg *msg = qup->msg;
+ u32 addr = msg->addr << 1;
+ u32 qup_tag;
+ int idx;
+ u32 val;
+- int ret = 0;
+
+ if (qup->pos == 0) {
+ val = QUP_TAG_START | addr;
+ idx = 1;
++ blk->tx_fifo_free--;
+ } else {
+ val = 0;
+ idx = 0;
+ }
+
+- while (qup->pos < msg->len) {
+- /* Check that there's space in the FIFO for our pair */
+- ret = check_for_fifo_space(qup);
+- if (ret)
+- return ret;
+-
++ while (blk->tx_fifo_free && qup->pos < msg->len) {
+ if (qup->pos == msg->len - 1)
+ qup_tag = QUP_TAG_STOP;
+ else
+@@ -481,11 +553,8 @@ static int qup_i2c_issue_write(struct qu
+
+ qup->pos++;
+ idx++;
++ blk->tx_fifo_free--;
+ }
+-
+- ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+-
+- return ret;
+ }
+
+ static void qup_i2c_set_blk_data(struct qup_i2c_dev *qup,
+@@ -1006,64 +1075,6 @@ err:
+ return ret;
+ }
+
+-static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg)
+-{
+- int ret;
+-
+- qup->msg = msg;
+- qup->pos = 0;
+-
+- enable_irq(qup->irq);
+-
+- qup_i2c_set_write_mode(qup, msg);
+-
+- ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+- if (ret)
+- goto err;
+-
+- writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
+-
+- do {
+- ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
+- if (ret)
+- goto err;
+-
+- ret = qup_i2c_issue_write(qup, msg);
+- if (ret)
+- goto err;
+-
+- ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+- if (ret)
+- goto err;
+-
+- ret = qup_i2c_wait_for_complete(qup, msg);
+- if (ret)
+- goto err;
+- } while (qup->pos < msg->len);
+-
+- /* Wait for the outstanding data in the fifo to drain */
+- ret = qup_i2c_wait_ready(qup, QUP_OUT_NOT_EMPTY, RESET_BIT, ONE_BYTE);
+-err:
+- disable_irq(qup->irq);
+- qup->msg = NULL;
+-
+- return ret;
+-}
+-
+-static void qup_i2c_set_read_mode(struct qup_i2c_dev *qup, int len)
+-{
+- if (len < qup->in_fifo_sz) {
+- /* FIFO mode */
+- writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE);
+- writel(len, qup->base + QUP_MX_READ_CNT);
+- } else {
+- /* BLOCK mode (transfer data on chunks) */
+- writel(QUP_INPUT_BLK_MODE | QUP_REPACK_EN,
+- qup->base + QUP_IO_MODE);
+- writel(len, qup->base + QUP_MX_INPUT_CNT);
+- }
+-}
+-
+ static void qup_i2c_set_read_mode_v2(struct qup_i2c_dev *qup, int len)
+ {
+ int tx_len = qup->blk.tx_tag_len;
+@@ -1086,44 +1097,27 @@ static void qup_i2c_set_read_mode_v2(str
+ }
+ }
+
+-static void qup_i2c_issue_read(struct qup_i2c_dev *qup, struct i2c_msg *msg)
+-{
+- u32 addr, len, val;
+-
+- addr = i2c_8bit_addr_from_msg(msg);
+-
+- /* 0 is used to specify a length 256 (QUP_READ_LIMIT) */
+- len = (msg->len == QUP_READ_LIMIT) ? 0 : msg->len;
+-
+- val = ((QUP_TAG_REC | len) << QUP_MSW_SHIFT) | QUP_TAG_START | addr;
+- writel(val, qup->base + QUP_OUT_FIFO_BASE);
+-}
+-
+-
+-static int qup_i2c_read_fifo(struct qup_i2c_dev *qup, struct i2c_msg *msg)
++static void qup_i2c_read_rx_fifo_v1(struct qup_i2c_dev *qup)
+ {
++ struct qup_i2c_block *blk = &qup->blk;
++ struct i2c_msg *msg = qup->msg;
+ u32 val = 0;
+- int idx;
+- int ret = 0;
++ int idx = 0;
+
+- for (idx = 0; qup->pos < msg->len; idx++) {
++ while (blk->fifo_available && qup->pos < msg->len) {
+ if ((idx & 1) == 0) {
+- /* Check that FIFO have data */
+- ret = qup_i2c_wait_ready(qup, QUP_IN_NOT_EMPTY,
+- SET_BIT, 4 * ONE_BYTE);
+- if (ret)
+- return ret;
+-
+ /* Reading 2 words at time */
+ val = readl(qup->base + QUP_IN_FIFO_BASE);
+-
+ msg->buf[qup->pos++] = val & 0xFF;
+ } else {
+ msg->buf[qup->pos++] = val >> QUP_MSW_SHIFT;
+ }
++ idx++;
++ blk->fifo_available--;
+ }
+
+- return ret;
++ if (qup->pos == msg->len)
++ blk->rx_bytes_read = true;
+ }
+
+ static int qup_i2c_read_fifo_v2(struct qup_i2c_dev *qup,
+@@ -1224,49 +1218,130 @@ err:
+ return ret;
+ }
+
+-static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg)
++static void qup_i2c_write_rx_tags_v1(struct qup_i2c_dev *qup)
+ {
+- int ret;
++ struct i2c_msg *msg = qup->msg;
++ u32 addr, len, val;
+
+- qup->msg = msg;
+- qup->pos = 0;
++ addr = i2c_8bit_addr_from_msg(msg);
+
+- enable_irq(qup->irq);
+- qup_i2c_set_read_mode(qup, msg->len);
++ /* 0 is used to specify a length 256 (QUP_READ_LIMIT) */
++ len = (msg->len == QUP_READ_LIMIT) ? 0 : msg->len;
++
++ val = ((QUP_TAG_REC | len) << QUP_MSW_SHIFT) | QUP_TAG_START | addr;
++ writel(val, qup->base + QUP_OUT_FIFO_BASE);
++}
++
++static void qup_i2c_conf_v1(struct qup_i2c_dev *qup)
++{
++ struct qup_i2c_block *blk = &qup->blk;
++ u32 qup_config = I2C_MINI_CORE | I2C_N_VAL;
++ u32 io_mode = QUP_REPACK_EN;
++
++ blk->is_tx_blk_mode =
++ blk->total_tx_len > qup->out_fifo_sz ? true : false;
++ blk->is_rx_blk_mode =
++ blk->total_rx_len > qup->in_fifo_sz ? true : false;
++
++ if (blk->is_tx_blk_mode) {
++ io_mode |= QUP_OUTPUT_BLK_MODE;
++ writel(0, qup->base + QUP_MX_WRITE_CNT);
++ writel(blk->total_tx_len, qup->base + QUP_MX_OUTPUT_CNT);
++ } else {
++ writel(0, qup->base + QUP_MX_OUTPUT_CNT);
++ writel(blk->total_tx_len, qup->base + QUP_MX_WRITE_CNT);
++ }
++
++ if (blk->total_rx_len) {
++ if (blk->is_rx_blk_mode) {
++ io_mode |= QUP_INPUT_BLK_MODE;
++ writel(0, qup->base + QUP_MX_READ_CNT);
++ writel(blk->total_rx_len, qup->base + QUP_MX_INPUT_CNT);
++ } else {
++ writel(0, qup->base + QUP_MX_INPUT_CNT);
++ writel(blk->total_rx_len, qup->base + QUP_MX_READ_CNT);
++ }
++ } else {
++ qup_config |= QUP_NO_INPUT;
++ }
++
++ writel(qup_config, qup->base + QUP_CONFIG);
++ writel(io_mode, qup->base + QUP_IO_MODE);
++}
+
++static void qup_i2c_clear_blk_v1(struct qup_i2c_block *blk)
++{
++ blk->tx_fifo_free = 0;
++ blk->fifo_available = 0;
++ blk->rx_bytes_read = false;
++}
++
++static int qup_i2c_conf_xfer_v1(struct qup_i2c_dev *qup, bool is_rx)
++{
++ struct qup_i2c_block *blk = &qup->blk;
++ int ret;
++
++ qup_i2c_clear_blk_v1(blk);
++ qup_i2c_conf_v1(qup);
+ ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+ if (ret)
+- goto err;
++ return ret;
+
+ writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
+
+ ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
+ if (ret)
+- goto err;
++ return ret;
++
++ reinit_completion(&qup->xfer);
++ enable_irq(qup->irq);
++ if (!blk->is_tx_blk_mode) {
++ blk->tx_fifo_free = qup->out_fifo_sz;
+
+- qup_i2c_issue_read(qup, msg);
++ if (is_rx)
++ qup_i2c_write_rx_tags_v1(qup);
++ else
++ qup_i2c_write_tx_fifo_v1(qup);
++ }
+
+ ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+ if (ret)
+ goto err;
+
+- do {
+- ret = qup_i2c_wait_for_complete(qup, msg);
+- if (ret)
+- goto err;
++ ret = qup_i2c_wait_for_complete(qup, qup->msg);
++ if (ret)
++ goto err;
+
+- ret = qup_i2c_read_fifo(qup, msg);
+- if (ret)
+- goto err;
+- } while (qup->pos < msg->len);
++ ret = qup_i2c_bus_active(qup, ONE_BYTE);
+
+ err:
+ disable_irq(qup->irq);
+- qup->msg = NULL;
+-
+ return ret;
+ }
+
++static int qup_i2c_write_one(struct qup_i2c_dev *qup)
++{
++ struct i2c_msg *msg = qup->msg;
++ struct qup_i2c_block *blk = &qup->blk;
++
++ qup->pos = 0;
++ blk->total_tx_len = msg->len + 1;
++ blk->total_rx_len = 0;
++
++ return qup_i2c_conf_xfer_v1(qup, false);
++}
++
++static int qup_i2c_read_one(struct qup_i2c_dev *qup)
++{
++ struct qup_i2c_block *blk = &qup->blk;
++
++ qup->pos = 0;
++ blk->total_tx_len = 2;
++ blk->total_rx_len = qup->msg->len;
++
++ return qup_i2c_conf_xfer_v1(qup, true);
++}
++
+ static int qup_i2c_xfer(struct i2c_adapter *adap,
+ struct i2c_msg msgs[],
+ int num)
+@@ -1305,10 +1380,11 @@ static int qup_i2c_xfer(struct i2c_adapt
+ goto out;
+ }
+
++ qup->msg = &msgs[idx];
+ if (msgs[idx].flags & I2C_M_RD)
+- ret = qup_i2c_read_one(qup, &msgs[idx]);
++ ret = qup_i2c_read_one(qup);
+ else
+- ret = qup_i2c_write_one(qup, &msgs[idx]);
++ ret = qup_i2c_write_one(qup);
+
+ if (ret)
+ break;
+@@ -1487,6 +1563,10 @@ static int qup_i2c_probe(struct platform
+ if (of_device_is_compatible(pdev->dev.of_node, "qcom,i2c-qup-v1.1.1")) {
+ qup->adap.algo = &qup_i2c_algo;
+ qup->adap.quirks = &qup_i2c_quirks;
++ qup->is_qup_v1 = true;
++ qup->write_tx_fifo = qup_i2c_write_tx_fifo_v1;
++ qup->read_rx_fifo = qup_i2c_read_rx_fifo_v1;
++ qup->write_rx_tags = qup_i2c_write_rx_tags_v1;
+ } else {
+ qup->adap.algo = &qup_i2c_algo_v2;
+ ret = qup_i2c_req_dma(qup);
--- /dev/null
+From 7545c7dba169c4c29ba5f6ab8706267a84c0febe Mon Sep 17 00:00:00 2001
+From: Abhishek Sahu <absahu@codeaurora.org>
+Date: Mon, 12 Mar 2018 18:45:02 +0530
+Subject: [PATCH 13/13] i2c: qup: reorganization of driver code to remove
+ polling for qup v2
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Following are the major issues in current driver code
+
+1. The current driver simply assumes the transfer completion
+ whenever its gets any non-error interrupts and then simply do the
+ polling of available/free bytes in FIFO.
+2. The block mode is not working properly since no handling in
+ being done for OUT_BLOCK_WRITE_REQ and IN_BLOCK_READ_READ.
+3. An i2c transfer can contain multiple message and QUP v2
+ supports reconfiguration during run in which the mode should be same
+ for all the sub transfer. Currently the mode is being programmed
+ before every sub transfer which is functionally wrong. If one message
+ is less than FIFO length and other message is greater than FIFO
+ length, then transfers will fail.
+
+Because of above, i2c v2 transfers of size greater than 64 are failing
+with following error message
+
+ i2c_qup 78b6000.i2c: timeout for fifo out full
+
+To make block mode working properly and move to use the interrupts
+instead of polling, major code reorganization is required. Following
+are the major changes done in this patch
+
+1. Remove the polling of TX FIFO free space and RX FIFO available
+ bytes and move to interrupts completely. QUP has QUP_MX_OUTPUT_DONE,
+ QUP_MX_INPUT_DONE, OUT_BLOCK_WRITE_REQ and IN_BLOCK_READ_REQ
+ interrupts to handle FIFO’s properly so check all these interrupts.
+2. Determine the mode for transfer before starting by checking
+ all the tx/rx data length in each message. The complete message can be
+ transferred either in DMA mode or Programmed IO by FIFO/Block mode.
+ in DMA mode, both tx and rx uses same mode but in PIO mode, the TX and
+ RX can be in different mode.
+3. During write, For FIFO mode, TX FIFO can be directly written
+ without checking for FIFO space. For block mode, the QUP will generate
+ OUT_BLOCK_WRITE_REQ interrupt whenever it has block size of available
+ space.
+4. During read, both TX and RX FIFO will be used. TX will be used
+ for writing tags and RX will be used for receiving the data. In QUP,
+ TX and RX can operate in separate mode so configure modes accordingly.
+5. For read FIFO mode, wait for QUP_MX_INPUT_DONE interrupt which
+ will be generated after all the bytes have been copied in RX FIFO. For
+ read Block mode, QUP will generate IN_BLOCK_READ_REQ interrupts
+ whenever it has block size of available data.
+6. Split the transfer in chunk of one QUP block size(256 bytes)
+ and schedule each block separately. QUP v2 supports reconfiguration
+ during run in which QUP can transfer multiple blocks without issuing a
+ stop events.
+7. Port the SMBus block read support for new code changes.
+
+Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
+Reviewed-by: Sricharan R <sricharan@codeaurora.org>
+Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
+---
+ drivers/i2c/busses/i2c-qup.c | 900 ++++++++++++++++++++---------------
+ 1 file changed, 515 insertions(+), 385 deletions(-)
+
+--- a/drivers/i2c/busses/i2c-qup.c
++++ b/drivers/i2c/busses/i2c-qup.c
+@@ -141,17 +141,40 @@
+ #define DEFAULT_SRC_CLK 20000000
+
+ /*
++ * Max tags length (start, stop and maximum 2 bytes address) for each QUP
++ * data transfer
++ */
++#define QUP_MAX_TAGS_LEN 4
++/* Max data length for each DATARD tags */
++#define RECV_MAX_DATA_LEN 254
++/* TAG length for DATA READ in RX FIFO */
++#define READ_RX_TAGS_LEN 2
++
++/*
+ * count: no of blocks
+ * pos: current block number
+ * tx_tag_len: tx tag length for current block
+ * rx_tag_len: rx tag length for current block
+ * data_len: remaining data length for current message
++ * cur_blk_len: data length for current block
+ * total_tx_len: total tx length including tag bytes for current QUP transfer
+ * total_rx_len: total rx length including tag bytes for current QUP transfer
++ * tx_fifo_data_pos: current byte number in TX FIFO word
+ * tx_fifo_free: number of free bytes in current QUP block write.
++ * rx_fifo_data_pos: current byte number in RX FIFO word
+ * fifo_available: number of available bytes in RX FIFO for current
+ * QUP block read
++ * tx_fifo_data: QUP TX FIFO write works on word basis (4 bytes). New byte write
++ * to TX FIFO will be appended in this data and will be written to
++ * TX FIFO when all the 4 bytes are available.
++ * rx_fifo_data: QUP RX FIFO read works on word basis (4 bytes). This will
++ * contains the 4 bytes of RX data.
++ * cur_data: pointer to tell cur data position for current message
++ * cur_tx_tags: pointer to tell cur position in tags
++ * tx_tags_sent: all tx tag bytes have been written in FIFO word
++ * send_last_word: for tx FIFO, last word send is pending in current block
+ * rx_bytes_read: if all the bytes have been read from rx FIFO.
++ * rx_tags_fetched: all the rx tag bytes have been fetched from rx fifo word
+ * is_tx_blk_mode: whether tx uses block or FIFO mode in case of non BAM xfer.
+ * is_rx_blk_mode: whether rx uses block or FIFO mode in case of non BAM xfer.
+ * tags: contains tx tag bytes for current QUP transfer
+@@ -162,10 +185,20 @@ struct qup_i2c_block {
+ int tx_tag_len;
+ int rx_tag_len;
+ int data_len;
++ int cur_blk_len;
+ int total_tx_len;
+ int total_rx_len;
++ int tx_fifo_data_pos;
+ int tx_fifo_free;
++ int rx_fifo_data_pos;
+ int fifo_available;
++ u32 tx_fifo_data;
++ u32 rx_fifo_data;
++ u8 *cur_data;
++ u8 *cur_tx_tags;
++ bool tx_tags_sent;
++ bool send_last_word;
++ bool rx_tags_fetched;
+ bool rx_bytes_read;
+ bool is_tx_blk_mode;
+ bool is_rx_blk_mode;
+@@ -198,6 +231,7 @@ struct qup_i2c_dev {
+ int out_blk_sz;
+ int in_blk_sz;
+
++ int blk_xfer_limit;
+ unsigned long one_byte_t;
+ unsigned long xfer_timeout;
+ struct qup_i2c_block blk;
+@@ -212,10 +246,10 @@ struct qup_i2c_dev {
+
+ /* To check if this is the last msg */
+ bool is_last;
+- bool is_qup_v1;
++ bool is_smbus_read;
+
+ /* To configure when bus is in run state */
+- int config_run;
++ u32 config_run;
+
+ /* dma parameters */
+ bool is_dma;
+@@ -223,6 +257,8 @@ struct qup_i2c_dev {
+ bool use_dma;
+ unsigned int max_xfer_sg_len;
+ unsigned int tag_buf_pos;
++ /* The threshold length above which block mode will be used */
++ unsigned int blk_mode_threshold;
+ struct dma_pool *dpool;
+ struct qup_i2c_tag start_tag;
+ struct qup_i2c_bam brx;
+@@ -287,9 +323,6 @@ static irqreturn_t qup_i2c_interrupt(int
+ goto done;
+ }
+
+- if (!qup->is_qup_v1)
+- goto done;
+-
+ if (opflags & QUP_OUT_SVC_FLAG) {
+ writel(QUP_OUT_SVC_FLAG, qup->base + QUP_OPERATIONAL);
+
+@@ -416,108 +449,6 @@ static int qup_i2c_bus_active(struct qup
+ return ret;
+ }
+
+-/**
+- * qup_i2c_wait_ready - wait for a give number of bytes in tx/rx path
+- * @qup: The qup_i2c_dev device
+- * @op: The bit/event to wait on
+- * @val: value of the bit to wait on, 0 or 1
+- * @len: The length the bytes to be transferred
+- */
+-static int qup_i2c_wait_ready(struct qup_i2c_dev *qup, int op, bool val,
+- int len)
+-{
+- unsigned long timeout;
+- u32 opflags;
+- u32 status;
+- u32 shift = __ffs(op);
+- int ret = 0;
+-
+- len *= qup->one_byte_t;
+- /* timeout after a wait of twice the max time */
+- timeout = jiffies + len * 4;
+-
+- for (;;) {
+- opflags = readl(qup->base + QUP_OPERATIONAL);
+- status = readl(qup->base + QUP_I2C_STATUS);
+-
+- if (((opflags & op) >> shift) == val) {
+- if ((op == QUP_OUT_NOT_EMPTY) && qup->is_last) {
+- if (!(status & I2C_STATUS_BUS_ACTIVE)) {
+- ret = 0;
+- goto done;
+- }
+- } else {
+- ret = 0;
+- goto done;
+- }
+- }
+-
+- if (time_after(jiffies, timeout)) {
+- ret = -ETIMEDOUT;
+- goto done;
+- }
+- usleep_range(len, len * 2);
+- }
+-
+-done:
+- if (qup->bus_err || qup->qup_err)
+- ret = (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO;
+-
+- return ret;
+-}
+-
+-static void qup_i2c_set_write_mode_v2(struct qup_i2c_dev *qup,
+- struct i2c_msg *msg)
+-{
+- /* Number of entries to shift out, including the tags */
+- int total = msg->len + qup->blk.tx_tag_len;
+-
+- total |= qup->config_run;
+-
+- if (total < qup->out_fifo_sz) {
+- /* FIFO mode */
+- writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE);
+- writel(total, qup->base + QUP_MX_WRITE_CNT);
+- } else {
+- /* BLOCK mode (transfer data on chunks) */
+- writel(QUP_OUTPUT_BLK_MODE | QUP_REPACK_EN,
+- qup->base + QUP_IO_MODE);
+- writel(total, qup->base + QUP_MX_OUTPUT_CNT);
+- }
+-}
+-
+-static int check_for_fifo_space(struct qup_i2c_dev *qup)
+-{
+- int ret;
+-
+- ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
+- if (ret)
+- goto out;
+-
+- ret = qup_i2c_wait_ready(qup, QUP_OUT_FULL,
+- RESET_BIT, 4 * ONE_BYTE);
+- if (ret) {
+- /* Fifo is full. Drain out the fifo */
+- ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+- if (ret)
+- goto out;
+-
+- ret = qup_i2c_wait_ready(qup, QUP_OUT_NOT_EMPTY,
+- RESET_BIT, 256 * ONE_BYTE);
+- if (ret) {
+- dev_err(qup->dev, "timeout for fifo out full");
+- goto out;
+- }
+-
+- ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
+- if (ret)
+- goto out;
+- }
+-
+-out:
+- return ret;
+-}
+-
+ static void qup_i2c_write_tx_fifo_v1(struct qup_i2c_dev *qup)
+ {
+ struct qup_i2c_block *blk = &qup->blk;
+@@ -560,60 +491,17 @@ static void qup_i2c_write_tx_fifo_v1(str
+ static void qup_i2c_set_blk_data(struct qup_i2c_dev *qup,
+ struct i2c_msg *msg)
+ {
+- memset(&qup->blk, 0, sizeof(qup->blk));
+-
++ qup->blk.pos = 0;
+ qup->blk.data_len = msg->len;
+- qup->blk.count = (msg->len + QUP_READ_LIMIT - 1) / QUP_READ_LIMIT;
+-
+- /* 4 bytes for first block and 2 writes for rest */
+- qup->blk.tx_tag_len = 4 + (qup->blk.count - 1) * 2;
+-
+- /* There are 2 tag bytes that are read in to fifo for every block */
+- if (msg->flags & I2C_M_RD)
+- qup->blk.rx_tag_len = qup->blk.count * 2;
+-}
+-
+-static int qup_i2c_send_data(struct qup_i2c_dev *qup, int tlen, u8 *tbuf,
+- int dlen, u8 *dbuf)
+-{
+- u32 val = 0, idx = 0, pos = 0, i = 0, t;
+- int len = tlen + dlen;
+- u8 *buf = tbuf;
+- int ret = 0;
+-
+- while (len > 0) {
+- ret = check_for_fifo_space(qup);
+- if (ret)
+- return ret;
+-
+- t = (len >= 4) ? 4 : len;
+-
+- while (idx < t) {
+- if (!i && (pos >= tlen)) {
+- buf = dbuf;
+- pos = 0;
+- i = 1;
+- }
+- val |= buf[pos++] << (idx++ * 8);
+- }
+-
+- writel(val, qup->base + QUP_OUT_FIFO_BASE);
+- idx = 0;
+- val = 0;
+- len -= 4;
+- }
+-
+- ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+-
+- return ret;
++ qup->blk.count = DIV_ROUND_UP(msg->len, qup->blk_xfer_limit);
+ }
+
+ static int qup_i2c_get_data_len(struct qup_i2c_dev *qup)
+ {
+ int data_len;
+
+- if (qup->blk.data_len > QUP_READ_LIMIT)
+- data_len = QUP_READ_LIMIT;
++ if (qup->blk.data_len > qup->blk_xfer_limit)
++ data_len = qup->blk_xfer_limit;
+ else
+ data_len = qup->blk.data_len;
+
+@@ -630,9 +518,9 @@ static int qup_i2c_set_tags_smb(u16 addr
+ {
+ int len = 0;
+
+- if (msg->len > 1) {
++ if (qup->is_smbus_read) {
+ tags[len++] = QUP_TAG_V2_DATARD_STOP;
+- tags[len++] = qup_i2c_get_data_len(qup) - 1;
++ tags[len++] = qup_i2c_get_data_len(qup);
+ } else {
+ tags[len++] = QUP_TAG_V2_START;
+ tags[len++] = addr & 0xff;
+@@ -694,24 +582,6 @@ static int qup_i2c_set_tags(u8 *tags, st
+ return len;
+ }
+
+-static int qup_i2c_issue_xfer_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg)
+-{
+- int data_len = 0, tag_len, index;
+- int ret;
+-
+- tag_len = qup_i2c_set_tags(qup->blk.tags, qup, msg);
+- index = msg->len - qup->blk.data_len;
+-
+- /* only tags are written for read */
+- if (!(msg->flags & I2C_M_RD))
+- data_len = qup_i2c_get_data_len(qup);
+-
+- ret = qup_i2c_send_data(qup, tag_len, qup->blk.tags,
+- data_len, &msg->buf[index]);
+- qup->blk.data_len -= data_len;
+-
+- return ret;
+-}
+
+ static void qup_i2c_bam_cb(void *data)
+ {
+@@ -778,6 +648,7 @@ static int qup_i2c_bam_make_desc(struct
+ u32 i = 0, tlen, tx_len = 0;
+ u8 *tags;
+
++ qup->blk_xfer_limit = QUP_READ_LIMIT;
+ qup_i2c_set_blk_data(qup, msg);
+
+ blocks = qup->blk.count;
+@@ -1026,7 +897,7 @@ static int qup_i2c_wait_for_complete(str
+ unsigned long left;
+ int ret = 0;
+
+- left = wait_for_completion_timeout(&qup->xfer, HZ);
++ left = wait_for_completion_timeout(&qup->xfer, qup->xfer_timeout);
+ if (!left) {
+ writel(1, qup->base + QUP_SW_RESET);
+ ret = -ETIMEDOUT;
+@@ -1038,65 +909,6 @@ static int qup_i2c_wait_for_complete(str
+ return ret;
+ }
+
+-static int qup_i2c_write_one_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg)
+-{
+- int ret = 0;
+-
+- qup->msg = msg;
+- qup->pos = 0;
+- enable_irq(qup->irq);
+- qup_i2c_set_blk_data(qup, msg);
+- qup_i2c_set_write_mode_v2(qup, msg);
+-
+- ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+- if (ret)
+- goto err;
+-
+- writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
+-
+- do {
+- ret = qup_i2c_issue_xfer_v2(qup, msg);
+- if (ret)
+- goto err;
+-
+- ret = qup_i2c_wait_for_complete(qup, msg);
+- if (ret)
+- goto err;
+-
+- qup->blk.pos++;
+- } while (qup->blk.pos < qup->blk.count);
+-
+- ret = qup_i2c_wait_ready(qup, QUP_OUT_NOT_EMPTY, RESET_BIT, ONE_BYTE);
+-
+-err:
+- disable_irq(qup->irq);
+- qup->msg = NULL;
+-
+- return ret;
+-}
+-
+-static void qup_i2c_set_read_mode_v2(struct qup_i2c_dev *qup, int len)
+-{
+- int tx_len = qup->blk.tx_tag_len;
+-
+- len += qup->blk.rx_tag_len;
+- len |= qup->config_run;
+- tx_len |= qup->config_run;
+-
+- if (len < qup->in_fifo_sz) {
+- /* FIFO mode */
+- writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE);
+- writel(tx_len, qup->base + QUP_MX_WRITE_CNT);
+- writel(len, qup->base + QUP_MX_READ_CNT);
+- } else {
+- /* BLOCK mode (transfer data on chunks) */
+- writel(QUP_INPUT_BLK_MODE | QUP_REPACK_EN,
+- qup->base + QUP_IO_MODE);
+- writel(tx_len, qup->base + QUP_MX_OUTPUT_CNT);
+- writel(len, qup->base + QUP_MX_INPUT_CNT);
+- }
+-}
+-
+ static void qup_i2c_read_rx_fifo_v1(struct qup_i2c_dev *qup)
+ {
+ struct qup_i2c_block *blk = &qup->blk;
+@@ -1120,104 +932,6 @@ static void qup_i2c_read_rx_fifo_v1(stru
+ blk->rx_bytes_read = true;
+ }
+
+-static int qup_i2c_read_fifo_v2(struct qup_i2c_dev *qup,
+- struct i2c_msg *msg)
+-{
+- u32 val;
+- int idx, pos = 0, ret = 0, total, msg_offset = 0;
+-
+- /*
+- * If the message length is already read in
+- * the first byte of the buffer, account for
+- * that by setting the offset
+- */
+- if (qup_i2c_check_msg_len(msg) && (msg->len > 1))
+- msg_offset = 1;
+- total = qup_i2c_get_data_len(qup);
+- total -= msg_offset;
+-
+- /* 2 extra bytes for read tags */
+- while (pos < (total + 2)) {
+- /* Check that FIFO have data */
+- ret = qup_i2c_wait_ready(qup, QUP_IN_NOT_EMPTY,
+- SET_BIT, 4 * ONE_BYTE);
+- if (ret) {
+- dev_err(qup->dev, "timeout for fifo not empty");
+- return ret;
+- }
+- val = readl(qup->base + QUP_IN_FIFO_BASE);
+-
+- for (idx = 0; idx < 4; idx++, val >>= 8, pos++) {
+- /* first 2 bytes are tag bytes */
+- if (pos < 2)
+- continue;
+-
+- if (pos >= (total + 2))
+- goto out;
+- msg->buf[qup->pos + msg_offset] = val & 0xff;
+- qup->pos++;
+- }
+- }
+-
+-out:
+- qup->blk.data_len -= total;
+-
+- return ret;
+-}
+-
+-static int qup_i2c_read_one_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg)
+-{
+- int ret = 0;
+-
+- qup->msg = msg;
+- qup->pos = 0;
+- enable_irq(qup->irq);
+- qup_i2c_set_blk_data(qup, msg);
+- qup_i2c_set_read_mode_v2(qup, msg->len);
+-
+- ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+- if (ret)
+- goto err;
+-
+- writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
+-
+- do {
+- ret = qup_i2c_issue_xfer_v2(qup, msg);
+- if (ret)
+- goto err;
+-
+- ret = qup_i2c_wait_for_complete(qup, msg);
+- if (ret)
+- goto err;
+-
+- ret = qup_i2c_read_fifo_v2(qup, msg);
+- if (ret)
+- goto err;
+-
+- qup->blk.pos++;
+-
+- /* Handle SMBus block read length */
+- if (qup_i2c_check_msg_len(msg) && (msg->len == 1)) {
+- if (msg->buf[0] > I2C_SMBUS_BLOCK_MAX) {
+- ret = -EPROTO;
+- goto err;
+- }
+- msg->len += msg->buf[0];
+- qup->pos = 0;
+- qup_i2c_set_blk_data(qup, msg);
+- /* set tag length for block read */
+- qup->blk.tx_tag_len = 2;
+- qup_i2c_set_read_mode_v2(qup, msg->buf[0]);
+- }
+- } while (qup->blk.pos < qup->blk.count);
+-
+-err:
+- disable_irq(qup->irq);
+- qup->msg = NULL;
+-
+- return ret;
+-}
+-
+ static void qup_i2c_write_rx_tags_v1(struct qup_i2c_dev *qup)
+ {
+ struct i2c_msg *msg = qup->msg;
+@@ -1404,13 +1118,434 @@ out:
+ return ret;
+ }
+
++/*
++ * Configure registers related with reconfiguration during run and call it
++ * before each i2c sub transfer.
++ */
++static void qup_i2c_conf_count_v2(struct qup_i2c_dev *qup)
++{
++ struct qup_i2c_block *blk = &qup->blk;
++ u32 qup_config = I2C_MINI_CORE | I2C_N_VAL_V2;
++
++ if (blk->is_tx_blk_mode)
++ writel(qup->config_run | blk->total_tx_len,
++ qup->base + QUP_MX_OUTPUT_CNT);
++ else
++ writel(qup->config_run | blk->total_tx_len,
++ qup->base + QUP_MX_WRITE_CNT);
++
++ if (blk->total_rx_len) {
++ if (blk->is_rx_blk_mode)
++ writel(qup->config_run | blk->total_rx_len,
++ qup->base + QUP_MX_INPUT_CNT);
++ else
++ writel(qup->config_run | blk->total_rx_len,
++ qup->base + QUP_MX_READ_CNT);
++ } else {
++ qup_config |= QUP_NO_INPUT;
++ }
++
++ writel(qup_config, qup->base + QUP_CONFIG);
++}
++
++/*
++ * Configure registers related with transfer mode (FIFO/Block)
++ * before starting of i2c transfer. It will be called only once in
++ * QUP RESET state.
++ */
++static void qup_i2c_conf_mode_v2(struct qup_i2c_dev *qup)
++{
++ struct qup_i2c_block *blk = &qup->blk;
++ u32 io_mode = QUP_REPACK_EN;
++
++ if (blk->is_tx_blk_mode) {
++ io_mode |= QUP_OUTPUT_BLK_MODE;
++ writel(0, qup->base + QUP_MX_WRITE_CNT);
++ } else {
++ writel(0, qup->base + QUP_MX_OUTPUT_CNT);
++ }
++
++ if (blk->is_rx_blk_mode) {
++ io_mode |= QUP_INPUT_BLK_MODE;
++ writel(0, qup->base + QUP_MX_READ_CNT);
++ } else {
++ writel(0, qup->base + QUP_MX_INPUT_CNT);
++ }
++
++ writel(io_mode, qup->base + QUP_IO_MODE);
++}
++
++/* Clear required variables before starting of any QUP v2 sub transfer. */
++static void qup_i2c_clear_blk_v2(struct qup_i2c_block *blk)
++{
++ blk->send_last_word = false;
++ blk->tx_tags_sent = false;
++ blk->tx_fifo_data = 0;
++ blk->tx_fifo_data_pos = 0;
++ blk->tx_fifo_free = 0;
++
++ blk->rx_tags_fetched = false;
++ blk->rx_bytes_read = false;
++ blk->rx_fifo_data = 0;
++ blk->rx_fifo_data_pos = 0;
++ blk->fifo_available = 0;
++}
++
++/* Receive data from RX FIFO for read message in QUP v2 i2c transfer. */
++static void qup_i2c_recv_data(struct qup_i2c_dev *qup)
++{
++ struct qup_i2c_block *blk = &qup->blk;
++ int j;
++
++ for (j = blk->rx_fifo_data_pos;
++ blk->cur_blk_len && blk->fifo_available;
++ blk->cur_blk_len--, blk->fifo_available--) {
++ if (j == 0)
++ blk->rx_fifo_data = readl(qup->base + QUP_IN_FIFO_BASE);
++
++ *(blk->cur_data++) = blk->rx_fifo_data;
++ blk->rx_fifo_data >>= 8;
++
++ if (j == 3)
++ j = 0;
++ else
++ j++;
++ }
++
++ blk->rx_fifo_data_pos = j;
++}
++
++/* Receive tags for read message in QUP v2 i2c transfer. */
++static void qup_i2c_recv_tags(struct qup_i2c_dev *qup)
++{
++ struct qup_i2c_block *blk = &qup->blk;
++
++ blk->rx_fifo_data = readl(qup->base + QUP_IN_FIFO_BASE);
++ blk->rx_fifo_data >>= blk->rx_tag_len * 8;
++ blk->rx_fifo_data_pos = blk->rx_tag_len;
++ blk->fifo_available -= blk->rx_tag_len;
++}
++
++/*
++ * Read the data and tags from RX FIFO. Since in read case, the tags will be
++ * preceded by received data bytes so
++ * 1. Check if rx_tags_fetched is false i.e. the start of QUP block so receive
++ * all tag bytes and discard that.
++ * 2. Read the data from RX FIFO. When all the data bytes have been read then
++ * set rx_bytes_read to true.
++ */
++static void qup_i2c_read_rx_fifo_v2(struct qup_i2c_dev *qup)
++{
++ struct qup_i2c_block *blk = &qup->blk;
++
++ if (!blk->rx_tags_fetched) {
++ qup_i2c_recv_tags(qup);
++ blk->rx_tags_fetched = true;
++ }
++
++ qup_i2c_recv_data(qup);
++ if (!blk->cur_blk_len)
++ blk->rx_bytes_read = true;
++}
++
++/*
++ * Write bytes in TX FIFO for write message in QUP v2 i2c transfer. QUP TX FIFO
++ * write works on word basis (4 bytes). Append new data byte write for TX FIFO
++ * in tx_fifo_data and write to TX FIFO when all the 4 bytes are present.
++ */
++static void
++qup_i2c_write_blk_data(struct qup_i2c_dev *qup, u8 **data, unsigned int *len)
++{
++ struct qup_i2c_block *blk = &qup->blk;
++ unsigned int j;
++
++ for (j = blk->tx_fifo_data_pos; *len && blk->tx_fifo_free;
++ (*len)--, blk->tx_fifo_free--) {
++ blk->tx_fifo_data |= *(*data)++ << (j * 8);
++ if (j == 3) {
++ writel(blk->tx_fifo_data,
++ qup->base + QUP_OUT_FIFO_BASE);
++ blk->tx_fifo_data = 0x0;
++ j = 0;
++ } else {
++ j++;
++ }
++ }
++
++ blk->tx_fifo_data_pos = j;
++}
++
++/* Transfer tags for read message in QUP v2 i2c transfer. */
++static void qup_i2c_write_rx_tags_v2(struct qup_i2c_dev *qup)
++{
++ struct qup_i2c_block *blk = &qup->blk;
++
++ qup_i2c_write_blk_data(qup, &blk->cur_tx_tags, &blk->tx_tag_len);
++ if (blk->tx_fifo_data_pos)
++ writel(blk->tx_fifo_data, qup->base + QUP_OUT_FIFO_BASE);
++}
++
++/*
++ * Write the data and tags in TX FIFO. Since in write case, both tags and data
++ * need to be written and QUP write tags can have maximum 256 data length, so
++ *
++ * 1. Check if tx_tags_sent is false i.e. the start of QUP block so write the
++ * tags to TX FIFO and set tx_tags_sent to true.
++ * 2. Check if send_last_word is true. It will be set when last few data bytes
++ * (less than 4 bytes) are reamining to be written in FIFO because of no FIFO
++ * space. All this data bytes are available in tx_fifo_data so write this
++ * in FIFO.
++ * 3. Write the data to TX FIFO and check for cur_blk_len. If it is non zero
++ * then more data is pending otherwise following 3 cases can be possible
++ * a. if tx_fifo_data_pos is zero i.e. all the data bytes in this block
++ * have been written in TX FIFO so nothing else is required.
++ * b. tx_fifo_free is non zero i.e tx FIFO is free so copy the remaining data
++ * from tx_fifo_data to tx FIFO. Since, qup_i2c_write_blk_data do write
++ * in 4 bytes and FIFO space is in multiple of 4 bytes so tx_fifo_free
++ * will be always greater than or equal to 4 bytes.
++ * c. tx_fifo_free is zero. In this case, last few bytes (less than 4
++ * bytes) are copied to tx_fifo_data but couldn't be sent because of
++ * FIFO full so make send_last_word true.
++ */
++static void qup_i2c_write_tx_fifo_v2(struct qup_i2c_dev *qup)
++{
++ struct qup_i2c_block *blk = &qup->blk;
++
++ if (!blk->tx_tags_sent) {
++ qup_i2c_write_blk_data(qup, &blk->cur_tx_tags,
++ &blk->tx_tag_len);
++ blk->tx_tags_sent = true;
++ }
++
++ if (blk->send_last_word)
++ goto send_last_word;
++
++ qup_i2c_write_blk_data(qup, &blk->cur_data, &blk->cur_blk_len);
++ if (!blk->cur_blk_len) {
++ if (!blk->tx_fifo_data_pos)
++ return;
++
++ if (blk->tx_fifo_free)
++ goto send_last_word;
++
++ blk->send_last_word = true;
++ }
++
++ return;
++
++send_last_word:
++ writel(blk->tx_fifo_data, qup->base + QUP_OUT_FIFO_BASE);
++}
++
++/*
++ * Main transfer function which read or write i2c data.
++ * The QUP v2 supports reconfiguration during run in which multiple i2c sub
++ * transfers can be scheduled.
++ */
++static int
++qup_i2c_conf_xfer_v2(struct qup_i2c_dev *qup, bool is_rx, bool is_first,
++ bool change_pause_state)
++{
++ struct qup_i2c_block *blk = &qup->blk;
++ struct i2c_msg *msg = qup->msg;
++ int ret;
++
++ /*
++ * Check if its SMBus Block read for which the top level read will be
++ * done into 2 QUP reads. One with message length 1 while other one is
++ * with actual length.
++ */
++ if (qup_i2c_check_msg_len(msg)) {
++ if (qup->is_smbus_read) {
++ /*
++ * If the message length is already read in
++ * the first byte of the buffer, account for
++ * that by setting the offset
++ */
++ blk->cur_data += 1;
++ is_first = false;
++ } else {
++ change_pause_state = false;
++ }
++ }
++
++ qup->config_run = is_first ? 0 : QUP_I2C_MX_CONFIG_DURING_RUN;
++
++ qup_i2c_clear_blk_v2(blk);
++ qup_i2c_conf_count_v2(qup);
++
++ /* If it is first sub transfer, then configure i2c bus clocks */
++ if (is_first) {
++ ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
++ if (ret)
++ return ret;
++
++ writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
++
++ ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
++ if (ret)
++ return ret;
++ }
++
++ reinit_completion(&qup->xfer);
++ enable_irq(qup->irq);
++ /*
++ * In FIFO mode, tx FIFO can be written directly while in block mode the
++ * it will be written after getting OUT_BLOCK_WRITE_REQ interrupt
++ */
++ if (!blk->is_tx_blk_mode) {
++ blk->tx_fifo_free = qup->out_fifo_sz;
++
++ if (is_rx)
++ qup_i2c_write_rx_tags_v2(qup);
++ else
++ qup_i2c_write_tx_fifo_v2(qup);
++ }
++
++ ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
++ if (ret)
++ goto err;
++
++ ret = qup_i2c_wait_for_complete(qup, msg);
++ if (ret)
++ goto err;
++
++ /* Move to pause state for all the transfers, except last one */
++ if (change_pause_state) {
++ ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
++ if (ret)
++ goto err;
++ }
++
++err:
++ disable_irq(qup->irq);
++ return ret;
++}
++
++/*
++ * Transfer one read/write message in i2c transfer. It splits the message into
++ * multiple of blk_xfer_limit data length blocks and schedule each
++ * QUP block individually.
++ */
++static int qup_i2c_xfer_v2_msg(struct qup_i2c_dev *qup, int msg_id, bool is_rx)
++{
++ int ret = 0;
++ unsigned int data_len, i;
++ struct i2c_msg *msg = qup->msg;
++ struct qup_i2c_block *blk = &qup->blk;
++ u8 *msg_buf = msg->buf;
++
++ qup->blk_xfer_limit = is_rx ? RECV_MAX_DATA_LEN : QUP_READ_LIMIT;
++ qup_i2c_set_blk_data(qup, msg);
++
++ for (i = 0; i < blk->count; i++) {
++ data_len = qup_i2c_get_data_len(qup);
++ blk->pos = i;
++ blk->cur_tx_tags = blk->tags;
++ blk->cur_blk_len = data_len;
++ blk->tx_tag_len =
++ qup_i2c_set_tags(blk->cur_tx_tags, qup, qup->msg);
++
++ blk->cur_data = msg_buf;
++
++ if (is_rx) {
++ blk->total_tx_len = blk->tx_tag_len;
++ blk->rx_tag_len = 2;
++ blk->total_rx_len = blk->rx_tag_len + data_len;
++ } else {
++ blk->total_tx_len = blk->tx_tag_len + data_len;
++ blk->total_rx_len = 0;
++ }
++
++ ret = qup_i2c_conf_xfer_v2(qup, is_rx, !msg_id && !i,
++ !qup->is_last || i < blk->count - 1);
++ if (ret)
++ return ret;
++
++ /* Handle SMBus block read length */
++ if (qup_i2c_check_msg_len(msg) && msg->len == 1 &&
++ !qup->is_smbus_read) {
++ if (msg->buf[0] > I2C_SMBUS_BLOCK_MAX)
++ return -EPROTO;
++
++ msg->len = msg->buf[0];
++ qup->is_smbus_read = true;
++ ret = qup_i2c_xfer_v2_msg(qup, msg_id, true);
++ qup->is_smbus_read = false;
++ if (ret)
++ return ret;
++
++ msg->len += 1;
++ }
++
++ msg_buf += data_len;
++ blk->data_len -= qup->blk_xfer_limit;
++ }
++
++ return ret;
++}
++
++/*
++ * QUP v2 supports 3 modes
++ * Programmed IO using FIFO mode : Less than FIFO size
++ * Programmed IO using Block mode : Greater than FIFO size
++ * DMA using BAM : Appropriate for any transaction size but the address should
++ * be DMA applicable
++ *
++ * This function determines the mode which will be used for this transfer. An
++ * i2c transfer contains multiple message. Following are the rules to determine
++ * the mode used.
++ * 1. Determine complete length, maximum tx and rx length for complete transfer.
++ * 2. If complete transfer length is greater than fifo size then use the DMA
++ * mode.
++ * 3. In FIFO or block mode, tx and rx can operate in different mode so check
++ * for maximum tx and rx length to determine mode.
++ */
++static int
++qup_i2c_determine_mode_v2(struct qup_i2c_dev *qup,
++ struct i2c_msg msgs[], int num)
++{
++ int idx;
++ bool no_dma = false;
++ unsigned int max_tx_len = 0, max_rx_len = 0, total_len = 0;
++
++ /* All i2c_msgs should be transferred using either dma or cpu */
++ for (idx = 0; idx < num; idx++) {
++ if (msgs[idx].len == 0)
++ return -EINVAL;
++
++ if (msgs[idx].flags & I2C_M_RD)
++ max_rx_len = max_t(unsigned int, max_rx_len,
++ msgs[idx].len);
++ else
++ max_tx_len = max_t(unsigned int, max_tx_len,
++ msgs[idx].len);
++
++ if (is_vmalloc_addr(msgs[idx].buf))
++ no_dma = true;
++
++ total_len += msgs[idx].len;
++ }
++
++ if (!no_dma && qup->is_dma &&
++ (total_len > qup->out_fifo_sz || total_len > qup->in_fifo_sz)) {
++ qup->use_dma = true;
++ } else {
++ qup->blk.is_tx_blk_mode = max_tx_len > qup->out_fifo_sz -
++ QUP_MAX_TAGS_LEN ? true : false;
++ qup->blk.is_rx_blk_mode = max_rx_len > qup->in_fifo_sz -
++ READ_RX_TAGS_LEN ? true : false;
++ }
++
++ return 0;
++}
++
+ static int qup_i2c_xfer_v2(struct i2c_adapter *adap,
+ struct i2c_msg msgs[],
+ int num)
+ {
+ struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
+ int ret, idx = 0;
+- unsigned int total_len = 0;
+
+ qup->bus_err = 0;
+ qup->qup_err = 0;
+@@ -1419,6 +1554,10 @@ static int qup_i2c_xfer_v2(struct i2c_ad
+ if (ret < 0)
+ goto out;
+
++ ret = qup_i2c_determine_mode_v2(qup, msgs, num);
++ if (ret)
++ goto out;
++
+ writel(1, qup->base + QUP_SW_RESET);
+ ret = qup_i2c_poll_state(qup, QUP_RESET_STATE);
+ if (ret)
+@@ -1428,60 +1567,35 @@ static int qup_i2c_xfer_v2(struct i2c_ad
+ writel(I2C_MINI_CORE | I2C_N_VAL_V2, qup->base + QUP_CONFIG);
+ writel(QUP_V2_TAGS_EN, qup->base + QUP_I2C_MASTER_GEN);
+
+- if ((qup->is_dma)) {
+- /* All i2c_msgs should be transferred using either dma or cpu */
+- for (idx = 0; idx < num; idx++) {
+- if (msgs[idx].len == 0) {
+- ret = -EINVAL;
+- goto out;
+- }
+-
+- if (is_vmalloc_addr(msgs[idx].buf))
+- break;
+-
+- total_len += msgs[idx].len;
+- }
+-
+- if (idx == num && (total_len > qup->out_fifo_sz ||
+- total_len > qup->in_fifo_sz))
+- qup->use_dma = true;
++ if (qup_i2c_poll_state_i2c_master(qup)) {
++ ret = -EIO;
++ goto out;
+ }
+
+- idx = 0;
++ if (qup->use_dma) {
++ reinit_completion(&qup->xfer);
++ ret = qup_i2c_bam_xfer(adap, &msgs[0], num);
++ qup->use_dma = false;
++ } else {
++ qup_i2c_conf_mode_v2(qup);
+
+- do {
+- if (msgs[idx].len == 0) {
+- ret = -EINVAL;
+- goto out;
+- }
++ for (idx = 0; idx < num; idx++) {
++ qup->msg = &msgs[idx];
++ qup->is_last = idx == (num - 1);
+
+- if (qup_i2c_poll_state_i2c_master(qup)) {
+- ret = -EIO;
+- goto out;
++ ret = qup_i2c_xfer_v2_msg(qup, idx,
++ !!(msgs[idx].flags & I2C_M_RD));
++ if (ret)
++ break;
+ }
++ qup->msg = NULL;
++ }
+
+- qup->is_last = (idx == (num - 1));
+- if (idx)
+- qup->config_run = QUP_I2C_MX_CONFIG_DURING_RUN;
+- else
+- qup->config_run = 0;
+-
+- reinit_completion(&qup->xfer);
+-
+- if (qup->use_dma) {
+- ret = qup_i2c_bam_xfer(adap, &msgs[idx], num);
+- qup->use_dma = false;
+- break;
+- } else {
+- if (msgs[idx].flags & I2C_M_RD)
+- ret = qup_i2c_read_one_v2(qup, &msgs[idx]);
+- else
+- ret = qup_i2c_write_one_v2(qup, &msgs[idx]);
+- }
+- } while ((idx++ < (num - 1)) && !ret);
++ if (!ret)
++ ret = qup_i2c_bus_active(qup, ONE_BYTE);
+
+ if (!ret)
+- ret = qup_i2c_change_state(qup, QUP_RESET_STATE);
++ qup_i2c_change_state(qup, QUP_RESET_STATE);
+
+ if (ret == 0)
+ ret = num;
+@@ -1545,6 +1659,7 @@ static int qup_i2c_probe(struct platform
+ u32 src_clk_freq = DEFAULT_SRC_CLK;
+ u32 clk_freq = DEFAULT_CLK_FREQ;
+ int blocks;
++ bool is_qup_v1;
+
+ qup = devm_kzalloc(&pdev->dev, sizeof(*qup), GFP_KERNEL);
+ if (!qup)
+@@ -1563,12 +1678,10 @@ static int qup_i2c_probe(struct platform
+ if (of_device_is_compatible(pdev->dev.of_node, "qcom,i2c-qup-v1.1.1")) {
+ qup->adap.algo = &qup_i2c_algo;
+ qup->adap.quirks = &qup_i2c_quirks;
+- qup->is_qup_v1 = true;
+- qup->write_tx_fifo = qup_i2c_write_tx_fifo_v1;
+- qup->read_rx_fifo = qup_i2c_read_rx_fifo_v1;
+- qup->write_rx_tags = qup_i2c_write_rx_tags_v1;
++ is_qup_v1 = true;
+ } else {
+ qup->adap.algo = &qup_i2c_algo_v2;
++ is_qup_v1 = false;
+ ret = qup_i2c_req_dma(qup);
+
+ if (ret == -EPROBE_DEFER)
+@@ -1694,14 +1807,31 @@ nodma:
+ ret = -EIO;
+ goto fail;
+ }
+- qup->out_blk_sz = blk_sizes[size] / 2;
++ qup->out_blk_sz = blk_sizes[size];
+
+ size = QUP_INPUT_BLOCK_SIZE(io_mode);
+ if (size >= ARRAY_SIZE(blk_sizes)) {
+ ret = -EIO;
+ goto fail;
+ }
+- qup->in_blk_sz = blk_sizes[size] / 2;
++ qup->in_blk_sz = blk_sizes[size];
++
++ if (is_qup_v1) {
++ /*
++ * in QUP v1, QUP_CONFIG uses N as 15 i.e 16 bits constitutes a
++ * single transfer but the block size is in bytes so divide the
++ * in_blk_sz and out_blk_sz by 2
++ */
++ qup->in_blk_sz /= 2;
++ qup->out_blk_sz /= 2;
++ qup->write_tx_fifo = qup_i2c_write_tx_fifo_v1;
++ qup->read_rx_fifo = qup_i2c_read_rx_fifo_v1;
++ qup->write_rx_tags = qup_i2c_write_rx_tags_v1;
++ } else {
++ qup->write_tx_fifo = qup_i2c_write_tx_fifo_v2;
++ qup->read_rx_fifo = qup_i2c_read_rx_fifo_v2;
++ qup->write_rx_tags = qup_i2c_write_rx_tags_v2;
++ }
+
+ size = QUP_OUTPUT_FIFO_SIZE(io_mode);
+ qup->out_fifo_sz = qup->out_blk_sz * (2 << size);
projects / openwrt / staging / rmilecki.git / commitdiff