target/linux/ipq40xx/patches-4.14/088-0009-i2c-qup-change-completion-timeout-according-to-trans.patch

   1 From ecb6e1e5f4352055a5761b945a833a925d51bf8d Mon Sep 17 00:00:00 2001
   2 From: Abhishek Sahu <absahu@codeaurora.org>
   3 Date: Mon, 12 Mar 2018 18:44:58 +0530
   4 Subject: [PATCH 09/13] i2c: qup: change completion timeout according to
   5  transfer length
   6
   7 Currently the completion timeout is being taken according to
   8 maximum transfer length which is too high if SCL is operating in
   9 high frequency. This patch calculates timeout on the basis of
  10 one-byte transfer time and uses the same for completion timeout.
  11
  12 Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
  13 Reviewed-by: Andy Gross <andy.gross@linaro.org>
  14 Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
  15 ---
  16  drivers/i2c/busses/i2c-qup.c | 13 ++++++++++---
  17  1 file changed, 10 insertions(+), 3 deletions(-)
  18
  19 --- a/drivers/i2c/busses/i2c-qup.c
  20 +++ b/drivers/i2c/busses/i2c-qup.c
  21 @@ -121,8 +121,12 @@
  22  #define MX_TX_RX_LEN                   SZ_64K
  23  #define MX_BLOCKS                      (MX_TX_RX_LEN / QUP_READ_LIMIT)
  24
  25 -/* Max timeout in ms for 32k bytes */
  26 -#define TOUT_MAX                       300
  27 +/*
  28 + * Minimum transfer timeout for i2c transfers in seconds. It will be added on
  29 + * the top of maximum transfer time calculated from i2c bus speed to compensate
  30 + * the overheads.
  31 + */
  32 +#define TOUT_MIN                       2
  33
  34  /* Default values. Use these if FW query fails */
  35  #define DEFAULT_CLK_FREQ 100000
  36 @@ -163,6 +167,7 @@ struct qup_i2c_dev {
  37         int                     in_blk_sz;
  38
  39         unsigned long           one_byte_t;
  40 +       unsigned long           xfer_timeout;
  41         struct qup_i2c_block    blk;
  42
  43         struct i2c_msg          *msg;
  44 @@ -849,7 +854,7 @@ static int qup_i2c_bam_do_xfer(struct qu
  45                 dma_async_issue_pending(qup->brx.dma);
  46         }
  47
  48 -       if (!wait_for_completion_timeout(&qup->xfer, TOUT_MAX * HZ)) {
  49 +       if (!wait_for_completion_timeout(&qup->xfer, qup->xfer_timeout)) {
  50                 dev_err(qup->dev, "normal trans timed out\n");
  51                 ret = -ETIMEDOUT;
  52         }
  53 @@ -1605,6 +1610,8 @@ nodma:
  54          */
  55         one_bit_t = (USEC_PER_SEC / clk_freq) + 1;
  56         qup->one_byte_t = one_bit_t * 9;
  57 +       qup->xfer_timeout = TOUT_MIN * HZ +
  58 +                           usecs_to_jiffies(MX_TX_RX_LEN * qup->one_byte_t);
  59
  60         dev_dbg(qup->dev, "IN:block:%d, fifo:%d, OUT:block:%d, fifo:%d\n",
  61                 qup->in_blk_sz, qup->in_fifo_sz,