add linux-v3.7
[openwrt/staging/noltari.git] / target / linux / lantiq / patches-3.7 / 0114-SPI-MIPS-lantiq-adds-spi-xway.patch
1 From db447f1a18106aa4d32438ab72ff57024b34cee4 Mon Sep 17 00:00:00 2001
2 From: John Crispin <blogic@openwrt.org>
3 Date: Thu, 16 Aug 2012 09:57:01 +0200
4 Subject: [PATCH 114/123] SPI: MIPS: lantiq: adds spi-xway
5
6 This patch adds support for the SPI core found on several Lantiq SoCs.
7 The Driver has been runtime tested in combination with m25p80 Flash Devices
8 on Amazon_SE and VR9.
9
10 Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
11 Signed-off-by: John Crispin <blogic@openwrt.org>
12 ---
13 drivers/spi/Kconfig | 8 +
14 drivers/spi/Makefile | 1 +
15 drivers/spi/spi-xway.c | 977 ++++++++++++++++++++++++++++++++++++++++++++++++
16 3 files changed, 986 insertions(+)
17 create mode 100644 drivers/spi/spi-xway.c
18
19 diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
20 index 1acae35..d79a587 100644
21 --- a/drivers/spi/Kconfig
22 +++ b/drivers/spi/Kconfig
23 @@ -434,6 +434,14 @@ config SPI_NUC900
24 help
25 SPI driver for Nuvoton NUC900 series ARM SoCs
26
27 +config SPI_XWAY
28 + tristate "Lantiq XWAY SPI controller"
29 + depends on LANTIQ && SOC_TYPE_XWAY
30 + select SPI_BITBANG
31 + help
32 + This driver supports the Lantiq SoC SPI controller in master
33 + mode.
34 +
35 #
36 # Add new SPI master controllers in alphabetical order above this line
37 #
38 diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
39 index c48df47..7e344a9 100644
40 --- a/drivers/spi/Makefile
41 +++ b/drivers/spi/Makefile
42 @@ -66,4 +66,5 @@ obj-$(CONFIG_SPI_TOPCLIFF_PCH) += spi-topcliff-pch.o
43 obj-$(CONFIG_SPI_TXX9) += spi-txx9.o
44 obj-$(CONFIG_SPI_XCOMM) += spi-xcomm.o
45 obj-$(CONFIG_SPI_XILINX) += spi-xilinx.o
46 +obj-$(CONFIG_SPI_XWAY) += spi-xway.o
47
48 diff --git a/drivers/spi/spi-xway.c b/drivers/spi/spi-xway.c
49 new file mode 100644
50 index 0000000..8441085
51 --- /dev/null
52 +++ b/drivers/spi/spi-xway.c
53 @@ -0,0 +1,977 @@
54 +/*
55 + * Lantiq SoC SPI controller
56 + *
57 + * Copyright (C) 2011 Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
58 + * Copyright (C) 2012 John Crispin <blogic@openwrt.org>
59 + *
60 + * This program is free software; you can distribute it and/or modify it
61 + * under the terms of the GNU General Public License (Version 2) as
62 + * published by the Free Software Foundation.
63 + */
64 +
65 +#include <linux/init.h>
66 +#include <linux/module.h>
67 +#include <linux/workqueue.h>
68 +#include <linux/platform_device.h>
69 +#include <linux/io.h>
70 +#include <linux/sched.h>
71 +#include <linux/delay.h>
72 +#include <linux/interrupt.h>
73 +#include <linux/completion.h>
74 +#include <linux/spinlock.h>
75 +#include <linux/err.h>
76 +#include <linux/clk.h>
77 +#include <linux/spi/spi.h>
78 +#include <linux/spi/spi_bitbang.h>
79 +#include <linux/of_irq.h>
80 +
81 +#include <lantiq_soc.h>
82 +
83 +#define LTQ_SPI_CLC 0x00 /* Clock control */
84 +#define LTQ_SPI_PISEL 0x04 /* Port input select */
85 +#define LTQ_SPI_ID 0x08 /* Identification */
86 +#define LTQ_SPI_CON 0x10 /* Control */
87 +#define LTQ_SPI_STAT 0x14 /* Status */
88 +#define LTQ_SPI_WHBSTATE 0x18 /* Write HW modified state */
89 +#define LTQ_SPI_TB 0x20 /* Transmit buffer */
90 +#define LTQ_SPI_RB 0x24 /* Receive buffer */
91 +#define LTQ_SPI_RXFCON 0x30 /* Receive FIFO control */
92 +#define LTQ_SPI_TXFCON 0x34 /* Transmit FIFO control */
93 +#define LTQ_SPI_FSTAT 0x38 /* FIFO status */
94 +#define LTQ_SPI_BRT 0x40 /* Baudrate timer */
95 +#define LTQ_SPI_BRSTAT 0x44 /* Baudrate timer status */
96 +#define LTQ_SPI_SFCON 0x60 /* Serial frame control */
97 +#define LTQ_SPI_SFSTAT 0x64 /* Serial frame status */
98 +#define LTQ_SPI_GPOCON 0x70 /* General purpose output control */
99 +#define LTQ_SPI_GPOSTAT 0x74 /* General purpose output status */
100 +#define LTQ_SPI_FGPO 0x78 /* Forced general purpose output */
101 +#define LTQ_SPI_RXREQ 0x80 /* Receive request */
102 +#define LTQ_SPI_RXCNT 0x84 /* Receive count */
103 +#define LTQ_SPI_DMACON 0xEC /* DMA control */
104 +#define LTQ_SPI_IRNEN 0xF4 /* Interrupt node enable */
105 +#define LTQ_SPI_IRNICR 0xF8 /* Interrupt node interrupt capture */
106 +#define LTQ_SPI_IRNCR 0xFC /* Interrupt node control */
107 +
108 +#define LTQ_SPI_CLC_SMC_SHIFT 16 /* Clock divider for sleep mode */
109 +#define LTQ_SPI_CLC_SMC_MASK 0xFF
110 +#define LTQ_SPI_CLC_RMC_SHIFT 8 /* Clock divider for normal run mode */
111 +#define LTQ_SPI_CLC_RMC_MASK 0xFF
112 +#define LTQ_SPI_CLC_DISS BIT(1) /* Disable status bit */
113 +#define LTQ_SPI_CLC_DISR BIT(0) /* Disable request bit */
114 +
115 +#define LTQ_SPI_ID_TXFS_SHIFT 24 /* Implemented TX FIFO size */
116 +#define LTQ_SPI_ID_TXFS_MASK 0x3F
117 +#define LTQ_SPI_ID_RXFS_SHIFT 16 /* Implemented RX FIFO size */
118 +#define LTQ_SPI_ID_RXFS_MASK 0x3F
119 +#define LTQ_SPI_ID_REV_MASK 0x1F /* Hardware revision number */
120 +#define LTQ_SPI_ID_CFG BIT(5) /* DMA interface support */
121 +
122 +#define LTQ_SPI_CON_BM_SHIFT 16 /* Data width selection */
123 +#define LTQ_SPI_CON_BM_MASK 0x1F
124 +#define LTQ_SPI_CON_EM BIT(24) /* Echo mode */
125 +#define LTQ_SPI_CON_IDLE BIT(23) /* Idle bit value */
126 +#define LTQ_SPI_CON_ENBV BIT(22) /* Enable byte valid control */
127 +#define LTQ_SPI_CON_RUEN BIT(12) /* Receive underflow error enable */
128 +#define LTQ_SPI_CON_TUEN BIT(11) /* Transmit underflow error enable */
129 +#define LTQ_SPI_CON_AEN BIT(10) /* Abort error enable */
130 +#define LTQ_SPI_CON_REN BIT(9) /* Receive overflow error enable */
131 +#define LTQ_SPI_CON_TEN BIT(8) /* Transmit overflow error enable */
132 +#define LTQ_SPI_CON_LB BIT(7) /* Loopback control */
133 +#define LTQ_SPI_CON_PO BIT(6) /* Clock polarity control */
134 +#define LTQ_SPI_CON_PH BIT(5) /* Clock phase control */
135 +#define LTQ_SPI_CON_HB BIT(4) /* Heading control */
136 +#define LTQ_SPI_CON_RXOFF BIT(1) /* Switch receiver off */
137 +#define LTQ_SPI_CON_TXOFF BIT(0) /* Switch transmitter off */
138 +
139 +#define LTQ_SPI_STAT_RXBV_MASK 0x7
140 +#define LTQ_SPI_STAT_RXBV_SHIFT 28
141 +#define LTQ_SPI_STAT_BSY BIT(13) /* Busy flag */
142 +#define LTQ_SPI_STAT_RUE BIT(12) /* Receive underflow error flag */
143 +#define LTQ_SPI_STAT_TUE BIT(11) /* Transmit underflow error flag */
144 +#define LTQ_SPI_STAT_AE BIT(10) /* Abort error flag */
145 +#define LTQ_SPI_STAT_RE BIT(9) /* Receive error flag */
146 +#define LTQ_SPI_STAT_TE BIT(8) /* Transmit error flag */
147 +#define LTQ_SPI_STAT_MS BIT(1) /* Master/slave select bit */
148 +#define LTQ_SPI_STAT_EN BIT(0) /* Enable bit */
149 +
150 +#define LTQ_SPI_WHBSTATE_SETTUE BIT(15) /* Set transmit underflow error flag */
151 +#define LTQ_SPI_WHBSTATE_SETAE BIT(14) /* Set abort error flag */
152 +#define LTQ_SPI_WHBSTATE_SETRE BIT(13) /* Set receive error flag */
153 +#define LTQ_SPI_WHBSTATE_SETTE BIT(12) /* Set transmit error flag */
154 +#define LTQ_SPI_WHBSTATE_CLRTUE BIT(11) /* Clear transmit underflow error
155 + flag */
156 +#define LTQ_SPI_WHBSTATE_CLRAE BIT(10) /* Clear abort error flag */
157 +#define LTQ_SPI_WHBSTATE_CLRRE BIT(9) /* Clear receive error flag */
158 +#define LTQ_SPI_WHBSTATE_CLRTE BIT(8) /* Clear transmit error flag */
159 +#define LTQ_SPI_WHBSTATE_SETME BIT(7) /* Set mode error flag */
160 +#define LTQ_SPI_WHBSTATE_CLRME BIT(6) /* Clear mode error flag */
161 +#define LTQ_SPI_WHBSTATE_SETRUE BIT(5) /* Set receive underflow error flag */
162 +#define LTQ_SPI_WHBSTATE_CLRRUE BIT(4) /* Clear receive underflow error flag */
163 +#define LTQ_SPI_WHBSTATE_SETMS BIT(3) /* Set master select bit */
164 +#define LTQ_SPI_WHBSTATE_CLRMS BIT(2) /* Clear master select bit */
165 +#define LTQ_SPI_WHBSTATE_SETEN BIT(1) /* Set enable bit (operational mode) */
166 +#define LTQ_SPI_WHBSTATE_CLREN BIT(0) /* Clear enable bit (config mode */
167 +#define LTQ_SPI_WHBSTATE_CLR_ERRORS 0x0F50
168 +
169 +#define LTQ_SPI_RXFCON_RXFITL_SHIFT 8 /* FIFO interrupt trigger level */
170 +#define LTQ_SPI_RXFCON_RXFITL_MASK 0x3F
171 +#define LTQ_SPI_RXFCON_RXFLU BIT(1) /* FIFO flush */
172 +#define LTQ_SPI_RXFCON_RXFEN BIT(0) /* FIFO enable */
173 +
174 +#define LTQ_SPI_TXFCON_TXFITL_SHIFT 8 /* FIFO interrupt trigger level */
175 +#define LTQ_SPI_TXFCON_TXFITL_MASK 0x3F
176 +#define LTQ_SPI_TXFCON_TXFLU BIT(1) /* FIFO flush */
177 +#define LTQ_SPI_TXFCON_TXFEN BIT(0) /* FIFO enable */
178 +
179 +#define LTQ_SPI_FSTAT_RXFFL_MASK 0x3f
180 +#define LTQ_SPI_FSTAT_RXFFL_SHIFT 0
181 +#define LTQ_SPI_FSTAT_TXFFL_MASK 0x3f
182 +#define LTQ_SPI_FSTAT_TXFFL_SHIFT 8
183 +
184 +#define LTQ_SPI_GPOCON_ISCSBN_SHIFT 8
185 +#define LTQ_SPI_GPOCON_INVOUTN_SHIFT 0
186 +
187 +#define LTQ_SPI_FGPO_SETOUTN_SHIFT 8
188 +#define LTQ_SPI_FGPO_CLROUTN_SHIFT 0
189 +
190 +#define LTQ_SPI_RXREQ_RXCNT_MASK 0xFFFF /* Receive count value */
191 +#define LTQ_SPI_RXCNT_TODO_MASK 0xFFFF /* Recevie to-do value */
192 +
193 +#define LTQ_SPI_IRNEN_F BIT(3) /* Frame end interrupt request */
194 +#define LTQ_SPI_IRNEN_E BIT(2) /* Error end interrupt request */
195 +#define LTQ_SPI_IRNEN_T BIT(1) /* Transmit end interrupt request */
196 +#define LTQ_SPI_IRNEN_R BIT(0) /* Receive end interrupt request */
197 +#define LTQ_SPI_IRNEN_ALL 0xF
198 +
199 +struct ltq_spi {
200 + struct spi_bitbang bitbang;
201 + struct completion done;
202 + spinlock_t lock;
203 +
204 + struct device *dev;
205 + void __iomem *base;
206 + struct clk *fpiclk;
207 + struct clk *spiclk;
208 +
209 + int status;
210 + int irq[3];
211 +
212 + const u8 *tx;
213 + u8 *rx;
214 + u32 tx_cnt;
215 + u32 rx_cnt;
216 + u32 len;
217 + struct spi_transfer *curr_transfer;
218 +
219 + u32 (*get_tx) (struct ltq_spi *);
220 +
221 + u16 txfs;
222 + u16 rxfs;
223 + unsigned dma_support:1;
224 + unsigned cfg_mode:1;
225 +};
226 +
227 +static inline struct ltq_spi *ltq_spi_to_hw(struct spi_device *spi)
228 +{
229 + return spi_master_get_devdata(spi->master);
230 +}
231 +
232 +static inline u32 ltq_spi_reg_read(struct ltq_spi *hw, u32 reg)
233 +{
234 + return ioread32be(hw->base + reg);
235 +}
236 +
237 +static inline void ltq_spi_reg_write(struct ltq_spi *hw, u32 val, u32 reg)
238 +{
239 + iowrite32be(val, hw->base + reg);
240 +}
241 +
242 +static inline void ltq_spi_reg_setbit(struct ltq_spi *hw, u32 bits, u32 reg)
243 +{
244 + u32 val;
245 +
246 + val = ltq_spi_reg_read(hw, reg);
247 + val |= bits;
248 + ltq_spi_reg_write(hw, val, reg);
249 +}
250 +
251 +static inline void ltq_spi_reg_clearbit(struct ltq_spi *hw, u32 bits, u32 reg)
252 +{
253 + u32 val;
254 +
255 + val = ltq_spi_reg_read(hw, reg);
256 + val &= ~bits;
257 + ltq_spi_reg_write(hw, val, reg);
258 +}
259 +
260 +static void ltq_spi_hw_enable(struct ltq_spi *hw)
261 +{
262 + u32 clc;
263 +
264 + /* Power-up module */
265 + clk_enable(hw->spiclk);
266 +
267 + /*
268 + * Set clock divider for run mode to 1 to
269 + * run at same frequency as FPI bus
270 + */
271 + clc = (1 << LTQ_SPI_CLC_RMC_SHIFT);
272 + ltq_spi_reg_write(hw, clc, LTQ_SPI_CLC);
273 +}
274 +
275 +static void ltq_spi_hw_disable(struct ltq_spi *hw)
276 +{
277 + /* Set clock divider to 0 and set module disable bit */
278 + ltq_spi_reg_write(hw, LTQ_SPI_CLC_DISS, LTQ_SPI_CLC);
279 +
280 + /* Power-down module */
281 + clk_disable(hw->spiclk);
282 +}
283 +
284 +static void ltq_spi_reset_fifos(struct ltq_spi *hw)
285 +{
286 + u32 val;
287 +
288 + /*
289 + * Enable and flush FIFOs. Set interrupt trigger level to
290 + * half of FIFO count implemented in hardware.
291 + */
292 + if (hw->txfs > 1) {
293 + val = hw->txfs << (LTQ_SPI_TXFCON_TXFITL_SHIFT - 1);
294 + val |= LTQ_SPI_TXFCON_TXFEN | LTQ_SPI_TXFCON_TXFLU;
295 + ltq_spi_reg_write(hw, val, LTQ_SPI_TXFCON);
296 + }
297 +
298 + if (hw->rxfs > 1) {
299 + val = hw->rxfs << (LTQ_SPI_RXFCON_RXFITL_SHIFT - 1);
300 + val |= LTQ_SPI_RXFCON_RXFEN | LTQ_SPI_RXFCON_RXFLU;
301 + ltq_spi_reg_write(hw, val, LTQ_SPI_RXFCON);
302 + }
303 +}
304 +
305 +static inline int ltq_spi_wait_ready(struct ltq_spi *hw)
306 +{
307 + u32 stat;
308 + unsigned long timeout;
309 +
310 + timeout = jiffies + msecs_to_jiffies(200);
311 +
312 + do {
313 + stat = ltq_spi_reg_read(hw, LTQ_SPI_STAT);
314 + if (!(stat & LTQ_SPI_STAT_BSY))
315 + return 0;
316 +
317 + cond_resched();
318 + } while (!time_after_eq(jiffies, timeout));
319 +
320 + dev_err(hw->dev, "SPI wait ready timed out stat: %x\n", stat);
321 +
322 + return -ETIMEDOUT;
323 +}
324 +
325 +static void ltq_spi_config_mode_set(struct ltq_spi *hw)
326 +{
327 + if (hw->cfg_mode)
328 + return;
329 +
330 + /*
331 + * Putting the SPI module in config mode is only safe if no
332 + * transfer is in progress as indicated by busy flag STATE.BSY.
333 + */
334 + if (ltq_spi_wait_ready(hw)) {
335 + ltq_spi_reset_fifos(hw);
336 + hw->status = -ETIMEDOUT;
337 + }
338 + ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_CLREN, LTQ_SPI_WHBSTATE);
339 +
340 + hw->cfg_mode = 1;
341 +}
342 +
343 +static void ltq_spi_run_mode_set(struct ltq_spi *hw)
344 +{
345 + if (!hw->cfg_mode)
346 + return;
347 +
348 + ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_SETEN, LTQ_SPI_WHBSTATE);
349 +
350 + hw->cfg_mode = 0;
351 +}
352 +
353 +static u32 ltq_spi_tx_word_u8(struct ltq_spi *hw)
354 +{
355 + const u8 *tx = hw->tx;
356 + u32 data = *tx++;
357 +
358 + hw->tx_cnt++;
359 + hw->tx++;
360 +
361 + return data;
362 +}
363 +
364 +static u32 ltq_spi_tx_word_u16(struct ltq_spi *hw)
365 +{
366 + const u16 *tx = (u16 *) hw->tx;
367 + u32 data = *tx++;
368 +
369 + hw->tx_cnt += 2;
370 + hw->tx += 2;
371 +
372 + return data;
373 +}
374 +
375 +static u32 ltq_spi_tx_word_u32(struct ltq_spi *hw)
376 +{
377 + const u32 *tx = (u32 *) hw->tx;
378 + u32 data = *tx++;
379 +
380 + hw->tx_cnt += 4;
381 + hw->tx += 4;
382 +
383 + return data;
384 +}
385 +
386 +static void ltq_spi_bits_per_word_set(struct spi_device *spi)
387 +{
388 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
389 + u32 bm;
390 + u8 bits_per_word = spi->bits_per_word;
391 +
392 + /*
393 + * Use either default value of SPI device or value
394 + * from current transfer.
395 + */
396 + if (hw->curr_transfer && hw->curr_transfer->bits_per_word)
397 + bits_per_word = hw->curr_transfer->bits_per_word;
398 +
399 + if (bits_per_word <= 8)
400 + hw->get_tx = ltq_spi_tx_word_u8;
401 + else if (bits_per_word <= 16)
402 + hw->get_tx = ltq_spi_tx_word_u16;
403 + else if (bits_per_word <= 32)
404 + hw->get_tx = ltq_spi_tx_word_u32;
405 +
406 + /* CON.BM value = bits_per_word - 1 */
407 + bm = (bits_per_word - 1) << LTQ_SPI_CON_BM_SHIFT;
408 +
409 + ltq_spi_reg_clearbit(hw, LTQ_SPI_CON_BM_MASK <<
410 + LTQ_SPI_CON_BM_SHIFT, LTQ_SPI_CON);
411 + ltq_spi_reg_setbit(hw, bm, LTQ_SPI_CON);
412 +}
413 +
414 +static void ltq_spi_speed_set(struct spi_device *spi)
415 +{
416 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
417 + u32 br, max_speed_hz, spi_clk;
418 + u32 speed_hz = spi->max_speed_hz;
419 +
420 + /*
421 + * Use either default value of SPI device or value
422 + * from current transfer.
423 + */
424 + if (hw->curr_transfer && hw->curr_transfer->speed_hz)
425 + speed_hz = hw->curr_transfer->speed_hz;
426 +
427 + /*
428 + * SPI module clock is derived from FPI bus clock dependent on
429 + * divider value in CLC.RMS which is always set to 1.
430 + */
431 + spi_clk = clk_get_rate(hw->fpiclk);
432 +
433 + /*
434 + * Maximum SPI clock frequency in master mode is half of
435 + * SPI module clock frequency. Maximum reload value of
436 + * baudrate generator BR is 2^16.
437 + */
438 + max_speed_hz = spi_clk / 2;
439 + if (speed_hz >= max_speed_hz)
440 + br = 0;
441 + else
442 + br = (max_speed_hz / speed_hz) - 1;
443 +
444 + if (br > 0xFFFF)
445 + br = 0xFFFF;
446 +
447 + ltq_spi_reg_write(hw, br, LTQ_SPI_BRT);
448 +}
449 +
450 +static void ltq_spi_clockmode_set(struct spi_device *spi)
451 +{
452 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
453 + u32 con;
454 +
455 + con = ltq_spi_reg_read(hw, LTQ_SPI_CON);
456 +
457 + /*
458 + * SPI mode mapping in CON register:
459 + * Mode CPOL CPHA CON.PO CON.PH
460 + * 0 0 0 0 1
461 + * 1 0 1 0 0
462 + * 2 1 0 1 1
463 + * 3 1 1 1 0
464 + */
465 + if (spi->mode & SPI_CPHA)
466 + con &= ~LTQ_SPI_CON_PH;
467 + else
468 + con |= LTQ_SPI_CON_PH;
469 +
470 + if (spi->mode & SPI_CPOL)
471 + con |= LTQ_SPI_CON_PO;
472 + else
473 + con &= ~LTQ_SPI_CON_PO;
474 +
475 + /* Set heading control */
476 + if (spi->mode & SPI_LSB_FIRST)
477 + con &= ~LTQ_SPI_CON_HB;
478 + else
479 + con |= LTQ_SPI_CON_HB;
480 +
481 + ltq_spi_reg_write(hw, con, LTQ_SPI_CON);
482 +}
483 +
484 +static void ltq_spi_xmit_set(struct ltq_spi *hw, struct spi_transfer *t)
485 +{
486 + u32 con;
487 +
488 + con = ltq_spi_reg_read(hw, LTQ_SPI_CON);
489 +
490 + if (t) {
491 + if (t->tx_buf && t->rx_buf) {
492 + con &= ~(LTQ_SPI_CON_TXOFF | LTQ_SPI_CON_RXOFF);
493 + } else if (t->rx_buf) {
494 + con &= ~LTQ_SPI_CON_RXOFF;
495 + con |= LTQ_SPI_CON_TXOFF;
496 + } else if (t->tx_buf) {
497 + con &= ~LTQ_SPI_CON_TXOFF;
498 + con |= LTQ_SPI_CON_RXOFF;
499 + }
500 + } else
501 + con |= (LTQ_SPI_CON_TXOFF | LTQ_SPI_CON_RXOFF);
502 +
503 + ltq_spi_reg_write(hw, con, LTQ_SPI_CON);
504 +}
505 +
506 +static void ltq_spi_internal_cs_activate(struct spi_device *spi)
507 +{
508 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
509 + u32 fgpo;
510 +
511 + fgpo = (1 << (spi->chip_select + LTQ_SPI_FGPO_CLROUTN_SHIFT));
512 + ltq_spi_reg_setbit(hw, fgpo, LTQ_SPI_FGPO);
513 +}
514 +
515 +static void ltq_spi_internal_cs_deactivate(struct spi_device *spi)
516 +{
517 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
518 + u32 fgpo;
519 +
520 + fgpo = (1 << (spi->chip_select + LTQ_SPI_FGPO_SETOUTN_SHIFT));
521 + ltq_spi_reg_setbit(hw, fgpo, LTQ_SPI_FGPO);
522 +}
523 +
524 +static void ltq_spi_chipselect(struct spi_device *spi, int cs)
525 +{
526 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
527 +
528 + switch (cs) {
529 + case BITBANG_CS_ACTIVE:
530 + ltq_spi_bits_per_word_set(spi);
531 + ltq_spi_speed_set(spi);
532 + ltq_spi_clockmode_set(spi);
533 + ltq_spi_run_mode_set(hw);
534 + ltq_spi_internal_cs_activate(spi);
535 + break;
536 +
537 + case BITBANG_CS_INACTIVE:
538 + ltq_spi_internal_cs_deactivate(spi);
539 + ltq_spi_config_mode_set(hw);
540 + break;
541 + }
542 +}
543 +
544 +static int ltq_spi_setup_transfer(struct spi_device *spi,
545 + struct spi_transfer *t)
546 +{
547 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
548 + u8 bits_per_word = spi->bits_per_word;
549 +
550 + hw->curr_transfer = t;
551 +
552 + if (t && t->bits_per_word)
553 + bits_per_word = t->bits_per_word;
554 +
555 + if (bits_per_word > 32)
556 + return -EINVAL;
557 +
558 + ltq_spi_config_mode_set(hw);
559 +
560 + return 0;
561 +}
562 +
563 +static int ltq_spi_setup(struct spi_device *spi)
564 +{
565 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
566 + u32 gpocon, fgpo;
567 +
568 + /* Set default word length to 8 if not set */
569 + if (!spi->bits_per_word)
570 + spi->bits_per_word = 8;
571 +
572 + if (spi->bits_per_word > 32)
573 + return -EINVAL;
574 +
575 + /*
576 + * Up to six GPIOs can be connected to the SPI module
577 + * via GPIO alternate function to control the chip select lines.
578 + */
579 + gpocon = (1 << (spi->chip_select +
580 + LTQ_SPI_GPOCON_ISCSBN_SHIFT));
581 +
582 + if (spi->mode & SPI_CS_HIGH)
583 + gpocon |= (1 << spi->chip_select);
584 +
585 + fgpo = (1 << (spi->chip_select + LTQ_SPI_FGPO_SETOUTN_SHIFT));
586 +
587 + ltq_spi_reg_setbit(hw, gpocon, LTQ_SPI_GPOCON);
588 + ltq_spi_reg_setbit(hw, fgpo, LTQ_SPI_FGPO);
589 +
590 + return 0;
591 +}
592 +
593 +static void ltq_spi_cleanup(struct spi_device *spi)
594 +{
595 +
596 +}
597 +
598 +static void ltq_spi_txfifo_write(struct ltq_spi *hw)
599 +{
600 + u32 fstat, data;
601 + u16 fifo_space;
602 +
603 + /* Determine how much FIFOs are free for TX data */
604 + fstat = ltq_spi_reg_read(hw, LTQ_SPI_FSTAT);
605 + fifo_space = hw->txfs - ((fstat >> LTQ_SPI_FSTAT_TXFFL_SHIFT) &
606 + LTQ_SPI_FSTAT_TXFFL_MASK);
607 +
608 + if (!fifo_space)
609 + return;
610 +
611 + while (hw->tx_cnt < hw->len && fifo_space) {
612 + data = hw->get_tx(hw);
613 + ltq_spi_reg_write(hw, data, LTQ_SPI_TB);
614 + fifo_space--;
615 + }
616 +}
617 +
618 +static void ltq_spi_rxfifo_read(struct ltq_spi *hw)
619 +{
620 + u32 fstat, data, *rx32;
621 + u16 fifo_fill;
622 + u8 rxbv, shift, *rx8;
623 +
624 + /* Determine how much FIFOs are filled with RX data */
625 + fstat = ltq_spi_reg_read(hw, LTQ_SPI_FSTAT);
626 + fifo_fill = ((fstat >> LTQ_SPI_FSTAT_RXFFL_SHIFT)
627 + & LTQ_SPI_FSTAT_RXFFL_MASK);
628 +
629 + if (!fifo_fill)
630 + return;
631 +
632 + /*
633 + * The 32 bit FIFO is always used completely independent from the
634 + * bits_per_word value. Thus four bytes have to be read at once
635 + * per FIFO.
636 + */
637 + rx32 = (u32 *) hw->rx;
638 + while (hw->len - hw->rx_cnt >= 4 && fifo_fill) {
639 + *rx32++ = ltq_spi_reg_read(hw, LTQ_SPI_RB);
640 + hw->rx_cnt += 4;
641 + hw->rx += 4;
642 + fifo_fill--;
643 + }
644 +
645 + /*
646 + * If there are remaining bytes, read byte count from STAT.RXBV
647 + * register and read the data byte-wise.
648 + */
649 + while (fifo_fill && hw->rx_cnt < hw->len) {
650 + rxbv = (ltq_spi_reg_read(hw, LTQ_SPI_STAT) >>
651 + LTQ_SPI_STAT_RXBV_SHIFT) & LTQ_SPI_STAT_RXBV_MASK;
652 + data = ltq_spi_reg_read(hw, LTQ_SPI_RB);
653 +
654 + shift = (rxbv - 1) * 8;
655 + rx8 = hw->rx;
656 +
657 + while (rxbv) {
658 + *rx8++ = (data >> shift) & 0xFF;
659 + rxbv--;
660 + shift -= 8;
661 + hw->rx_cnt++;
662 + hw->rx++;
663 + }
664 +
665 + fifo_fill--;
666 + }
667 +}
668 +
669 +static void ltq_spi_rxreq_set(struct ltq_spi *hw)
670 +{
671 + u32 rxreq, rxreq_max, rxtodo;
672 +
673 + rxtodo = ltq_spi_reg_read(hw, LTQ_SPI_RXCNT) & LTQ_SPI_RXCNT_TODO_MASK;
674 +
675 + /*
676 + * In RX-only mode the serial clock is activated only after writing
677 + * the expected amount of RX bytes into RXREQ register.
678 + * To avoid receive overflows at high clocks it is better to request
679 + * only the amount of bytes that fits into all FIFOs. This value
680 + * depends on the FIFO size implemented in hardware.
681 + */
682 + rxreq = hw->len - hw->rx_cnt;
683 + rxreq_max = hw->rxfs << 2;
684 + rxreq = min(rxreq_max, rxreq);
685 +
686 + if (!rxtodo && rxreq)
687 + ltq_spi_reg_write(hw, rxreq, LTQ_SPI_RXREQ);
688 +}
689 +
690 +static inline void ltq_spi_complete(struct ltq_spi *hw)
691 +{
692 + complete(&hw->done);
693 +}
694 +
695 +irqreturn_t ltq_spi_tx_irq(int irq, void *data)
696 +{
697 + struct ltq_spi *hw = data;
698 + unsigned long flags;
699 + int completed = 0;
700 +
701 + spin_lock_irqsave(&hw->lock, flags);
702 +
703 + if (hw->tx_cnt < hw->len)
704 + ltq_spi_txfifo_write(hw);
705 +
706 + if (hw->tx_cnt == hw->len)
707 + completed = 1;
708 +
709 + spin_unlock_irqrestore(&hw->lock, flags);
710 +
711 + if (completed)
712 + ltq_spi_complete(hw);
713 +
714 + return IRQ_HANDLED;
715 +}
716 +
717 +irqreturn_t ltq_spi_rx_irq(int irq, void *data)
718 +{
719 + struct ltq_spi *hw = data;
720 + unsigned long flags;
721 + int completed = 0;
722 +
723 + spin_lock_irqsave(&hw->lock, flags);
724 +
725 + if (hw->rx_cnt < hw->len) {
726 + ltq_spi_rxfifo_read(hw);
727 +
728 + if (hw->tx && hw->tx_cnt < hw->len)
729 + ltq_spi_txfifo_write(hw);
730 + }
731 +
732 + if (hw->rx_cnt == hw->len)
733 + completed = 1;
734 + else if (!hw->tx)
735 + ltq_spi_rxreq_set(hw);
736 +
737 + spin_unlock_irqrestore(&hw->lock, flags);
738 +
739 + if (completed)
740 + ltq_spi_complete(hw);
741 +
742 + return IRQ_HANDLED;
743 +}
744 +
745 +irqreturn_t ltq_spi_err_irq(int irq, void *data)
746 +{
747 + struct ltq_spi *hw = data;
748 + unsigned long flags;
749 +
750 + spin_lock_irqsave(&hw->lock, flags);
751 +
752 + /* Disable all interrupts */
753 + ltq_spi_reg_clearbit(hw, LTQ_SPI_IRNEN_ALL, LTQ_SPI_IRNEN);
754 +
755 + /* Clear all error flags */
756 + ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_CLR_ERRORS, LTQ_SPI_WHBSTATE);
757 +
758 + /* Flush FIFOs */
759 + ltq_spi_reg_setbit(hw, LTQ_SPI_RXFCON_RXFLU, LTQ_SPI_RXFCON);
760 + ltq_spi_reg_setbit(hw, LTQ_SPI_TXFCON_TXFLU, LTQ_SPI_TXFCON);
761 +
762 + hw->status = -EIO;
763 + spin_unlock_irqrestore(&hw->lock, flags);
764 +
765 + ltq_spi_complete(hw);
766 +
767 + return IRQ_HANDLED;
768 +}
769 +
770 +static int ltq_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
771 +{
772 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
773 + u32 irq_flags = 0;
774 +
775 + hw->tx = t->tx_buf;
776 + hw->rx = t->rx_buf;
777 + hw->len = t->len;
778 + hw->tx_cnt = 0;
779 + hw->rx_cnt = 0;
780 + hw->status = 0;
781 + INIT_COMPLETION(hw->done);
782 +
783 + ltq_spi_xmit_set(hw, t);
784 +
785 + /* Enable error interrupts */
786 + ltq_spi_reg_setbit(hw, LTQ_SPI_IRNEN_E, LTQ_SPI_IRNEN);
787 +
788 + if (hw->tx) {
789 + /* Initially fill TX FIFO with as much data as possible */
790 + ltq_spi_txfifo_write(hw);
791 + irq_flags |= LTQ_SPI_IRNEN_T;
792 +
793 + /* Always enable RX interrupt in Full Duplex mode */
794 + if (hw->rx)
795 + irq_flags |= LTQ_SPI_IRNEN_R;
796 + } else if (hw->rx) {
797 + /* Start RX clock */
798 + ltq_spi_rxreq_set(hw);
799 +
800 + /* Enable RX interrupt to receive data from RX FIFOs */
801 + irq_flags |= LTQ_SPI_IRNEN_R;
802 + }
803 +
804 + /* Enable TX or RX interrupts */
805 + ltq_spi_reg_setbit(hw, irq_flags, LTQ_SPI_IRNEN);
806 + wait_for_completion_interruptible(&hw->done);
807 +
808 + /* Disable all interrupts */
809 + ltq_spi_reg_clearbit(hw, LTQ_SPI_IRNEN_ALL, LTQ_SPI_IRNEN);
810 +
811 + /*
812 + * Return length of current transfer for bitbang utility code if
813 + * no errors occured during transmission.
814 + */
815 + if (!hw->status)
816 + hw->status = hw->len;
817 +
818 + return hw->status;
819 +}
820 +
821 +static const struct ltq_spi_irq_map {
822 + char *name;
823 + irq_handler_t handler;
824 +} ltq_spi_irqs[] = {
825 + { "spi_rx", ltq_spi_rx_irq },
826 + { "spi_tx", ltq_spi_tx_irq },
827 + { "spi_err", ltq_spi_err_irq },
828 +};
829 +
830 +static int __devinit ltq_spi_probe(struct platform_device *pdev)
831 +{
832 + struct resource irqres[3];
833 + struct spi_master *master;
834 + struct resource *r;
835 + struct ltq_spi *hw;
836 + int ret, i;
837 + u32 data, id;
838 +
839 + if (of_irq_to_resource_table(pdev->dev.of_node, irqres, 3) != 3) {
840 + dev_err(&pdev->dev, "IRQ settings missing in device tree\n");
841 + return -EINVAL;
842 + }
843 +
844 + master = spi_alloc_master(&pdev->dev, sizeof(struct ltq_spi));
845 + if (!master) {
846 + dev_err(&pdev->dev, "spi_alloc_master\n");
847 + ret = -ENOMEM;
848 + goto err;
849 + }
850 +
851 + hw = spi_master_get_devdata(master);
852 +
853 + r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
854 + if (r == NULL) {
855 + dev_err(&pdev->dev, "platform_get_resource\n");
856 + ret = -ENOENT;
857 + goto err_master;
858 + }
859 +
860 + r = devm_request_mem_region(&pdev->dev, r->start, resource_size(r),
861 + pdev->name);
862 + if (!r) {
863 + dev_err(&pdev->dev, "failed to request memory region\n");
864 + ret = -ENXIO;
865 + goto err_master;
866 + }
867 +
868 + hw->base = devm_ioremap_nocache(&pdev->dev, r->start, resource_size(r));
869 + if (!hw->base) {
870 + dev_err(&pdev->dev, "failed to remap memory region\n");
871 + ret = -ENXIO;
872 + goto err_master;
873 + }
874 +
875 + memset(hw->irq, 0, sizeof(hw->irq));
876 + for (i = 0; i < ARRAY_SIZE(ltq_spi_irqs); i++) {
877 + hw->irq[i] = irqres[i].start;
878 + ret = request_irq(hw->irq[i], ltq_spi_irqs[i].handler,
879 + 0, ltq_spi_irqs[i].name, hw);
880 + if (ret) {
881 + dev_err(&pdev->dev, "failed to request %s irq (%d)\n",
882 + ltq_spi_irqs[i].name, hw->irq[i]);
883 + goto err_irq;
884 + }
885 + }
886 +
887 + hw->fpiclk = clk_get_fpi();
888 + if (IS_ERR(hw->fpiclk)) {
889 + dev_err(&pdev->dev, "failed to get fpi clock\n");
890 + ret = PTR_ERR(hw->fpiclk);
891 + goto err_clk;
892 + }
893 +
894 + hw->spiclk = clk_get(&pdev->dev, NULL);
895 + if (IS_ERR(hw->spiclk)) {
896 + dev_err(&pdev->dev, "failed to get spi clock gate\n");
897 + ret = PTR_ERR(hw->spiclk);
898 + goto err_clk;
899 + }
900 +
901 + hw->bitbang.master = spi_master_get(master);
902 + hw->bitbang.chipselect = ltq_spi_chipselect;
903 + hw->bitbang.setup_transfer = ltq_spi_setup_transfer;
904 + hw->bitbang.txrx_bufs = ltq_spi_txrx_bufs;
905 +
906 + if (of_machine_is_compatible("lantiq,ase"))
907 + master->num_chipselect = 3;
908 + else
909 + master->num_chipselect = 6;
910 + master->bus_num = pdev->id;
911 + master->setup = ltq_spi_setup;
912 + master->cleanup = ltq_spi_cleanup;
913 + master->dev.of_node = pdev->dev.of_node;
914 +
915 + hw->dev = &pdev->dev;
916 + init_completion(&hw->done);
917 + spin_lock_init(&hw->lock);
918 +
919 + ltq_spi_hw_enable(hw);
920 +
921 + /* Read module capabilities */
922 + id = ltq_spi_reg_read(hw, LTQ_SPI_ID);
923 + hw->txfs = (id >> LTQ_SPI_ID_TXFS_SHIFT) & LTQ_SPI_ID_TXFS_MASK;
924 + hw->rxfs = (id >> LTQ_SPI_ID_TXFS_SHIFT) & LTQ_SPI_ID_TXFS_MASK;
925 + hw->dma_support = (id & LTQ_SPI_ID_CFG) ? 1 : 0;
926 +
927 + ltq_spi_config_mode_set(hw);
928 +
929 + /* Enable error checking, disable TX/RX, set idle value high */
930 + data = LTQ_SPI_CON_RUEN | LTQ_SPI_CON_AEN |
931 + LTQ_SPI_CON_TEN | LTQ_SPI_CON_REN |
932 + LTQ_SPI_CON_TXOFF | LTQ_SPI_CON_RXOFF | LTQ_SPI_CON_IDLE;
933 + ltq_spi_reg_write(hw, data, LTQ_SPI_CON);
934 +
935 + /* Enable master mode and clear error flags */
936 + ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_SETMS |
937 + LTQ_SPI_WHBSTATE_CLR_ERRORS, LTQ_SPI_WHBSTATE);
938 +
939 + /* Reset GPIO/CS registers */
940 + ltq_spi_reg_write(hw, 0x0, LTQ_SPI_GPOCON);
941 + ltq_spi_reg_write(hw, 0xFF00, LTQ_SPI_FGPO);
942 +
943 + /* Enable and flush FIFOs */
944 + ltq_spi_reset_fifos(hw);
945 +
946 + ret = spi_bitbang_start(&hw->bitbang);
947 + if (ret) {
948 + dev_err(&pdev->dev, "spi_bitbang_start failed\n");
949 + goto err_bitbang;
950 + }
951 +
952 + platform_set_drvdata(pdev, hw);
953 +
954 + pr_info("Lantiq SoC SPI controller rev %u (TXFS %u, RXFS %u, DMA %u)\n",
955 + id & LTQ_SPI_ID_REV_MASK, hw->txfs, hw->rxfs, hw->dma_support);
956 +
957 + return 0;
958 +
959 +err_bitbang:
960 + ltq_spi_hw_disable(hw);
961 +
962 +err_clk:
963 + if (hw->fpiclk)
964 + clk_put(hw->fpiclk);
965 + if (hw->spiclk)
966 + clk_put(hw->spiclk);
967 +
968 +err_irq:
969 + clk_put(hw->fpiclk);
970 +
971 + for (; i > 0; i--)
972 + free_irq(hw->irq[i], hw);
973 +
974 +err_master:
975 + spi_master_put(master);
976 +
977 +err:
978 + return ret;
979 +}
980 +
981 +static int __devexit ltq_spi_remove(struct platform_device *pdev)
982 +{
983 + struct ltq_spi *hw = platform_get_drvdata(pdev);
984 + int ret, i;
985 +
986 + ret = spi_bitbang_stop(&hw->bitbang);
987 + if (ret)
988 + return ret;
989 +
990 + platform_set_drvdata(pdev, NULL);
991 +
992 + ltq_spi_config_mode_set(hw);
993 + ltq_spi_hw_disable(hw);
994 +
995 + for (i = 0; i < ARRAY_SIZE(hw->irq); i++)
996 + if (0 < hw->irq[i])
997 + free_irq(hw->irq[i], hw);
998 +
999 + if (hw->fpiclk)
1000 + clk_put(hw->fpiclk);
1001 + if (hw->spiclk)
1002 + clk_put(hw->spiclk);
1003 +
1004 + spi_master_put(hw->bitbang.master);
1005 +
1006 + return 0;
1007 +}
1008 +
1009 +static const struct of_device_id ltq_spi_match[] = {
1010 + { .compatible = "lantiq,spi-xway" },
1011 + {},
1012 +};
1013 +MODULE_DEVICE_TABLE(of, ltq_spi_match);
1014 +
1015 +static struct platform_driver ltq_spi_driver = {
1016 + .probe = ltq_spi_probe,
1017 + .remove = __devexit_p(ltq_spi_remove),
1018 + .driver = {
1019 + .name = "spi-xway",
1020 + .owner = THIS_MODULE,
1021 + .of_match_table = ltq_spi_match,
1022 + },
1023 +};
1024 +
1025 +module_platform_driver(ltq_spi_driver);
1026 +
1027 +MODULE_DESCRIPTION("Lantiq SoC SPI controller driver");
1028 +MODULE_AUTHOR("Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>");
1029 +MODULE_LICENSE("GPL");
1030 +MODULE_ALIAS("platform:spi-xway");
1031 --
1032 1.7.10.4
1033