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1/*
2 * OMAP7xx SPI 100k controller driver
3 * Author: Fabrice Crohas <fcrohas@gmail.com>
4 * from original omap1_mcspi driver
5 *
6 * Copyright (C) 2005, 2006 Nokia Corporation
7 * Author: Samuel Ortiz <samuel.ortiz@nokia.com> and
8 * Juha Yrj�l� <juha.yrjola@nokia.com>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 */
20#include <linux/kernel.h>
21#include <linux/init.h>
22#include <linux/interrupt.h>
23#include <linux/module.h>
24#include <linux/device.h>
25#include <linux/delay.h>
26#include <linux/platform_device.h>
27#include <linux/pm_runtime.h>
28#include <linux/err.h>
29#include <linux/clk.h>
30#include <linux/io.h>
31#include <linux/gpio.h>
32#include <linux/slab.h>
33
34#include <linux/spi/spi.h>
35
36#define OMAP1_SPI100K_MAX_FREQ 48000000
37
38#define ICR_SPITAS (OMAP7XX_ICR_BASE + 0x12)
39
40#define SPI_SETUP1 0x00
41#define SPI_SETUP2 0x02
42#define SPI_CTRL 0x04
43#define SPI_STATUS 0x06
44#define SPI_TX_LSB 0x08
45#define SPI_TX_MSB 0x0a
46#define SPI_RX_LSB 0x0c
47#define SPI_RX_MSB 0x0e
48
49#define SPI_SETUP1_INT_READ_ENABLE (1UL << 5)
50#define SPI_SETUP1_INT_WRITE_ENABLE (1UL << 4)
51#define SPI_SETUP1_CLOCK_DIVISOR(x) ((x) << 1)
52#define SPI_SETUP1_CLOCK_ENABLE (1UL << 0)
53
54#define SPI_SETUP2_ACTIVE_EDGE_FALLING (0UL << 0)
55#define SPI_SETUP2_ACTIVE_EDGE_RISING (1UL << 0)
56#define SPI_SETUP2_NEGATIVE_LEVEL (0UL << 5)
57#define SPI_SETUP2_POSITIVE_LEVEL (1UL << 5)
58#define SPI_SETUP2_LEVEL_TRIGGER (0UL << 10)
59#define SPI_SETUP2_EDGE_TRIGGER (1UL << 10)
60
61#define SPI_CTRL_SEN(x) ((x) << 7)
62#define SPI_CTRL_WORD_SIZE(x) (((x) - 1) << 2)
63#define SPI_CTRL_WR (1UL << 1)
64#define SPI_CTRL_RD (1UL << 0)
65
66#define SPI_STATUS_WE (1UL << 1)
67#define SPI_STATUS_RD (1UL << 0)
68
69/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
70 * cache operations; better heuristics consider wordsize and bitrate.
71 */
72#define DMA_MIN_BYTES 8
73
74#define SPI_RUNNING 0
75#define SPI_SHUTDOWN 1
76
77struct omap1_spi100k {
78 struct clk *ick;
79 struct clk *fck;
80
81 /* Virtual base address of the controller */
82 void __iomem *base;
83};
84
85struct omap1_spi100k_cs {
86 void __iomem *base;
87 int word_len;
88};
89
90static void spi100k_enable_clock(struct spi_master *master)
91{
92 unsigned int val;
93 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
94
95 /* enable SPI */
96 val = readw(spi100k->base + SPI_SETUP1);
97 val |= SPI_SETUP1_CLOCK_ENABLE;
98 writew(val, spi100k->base + SPI_SETUP1);
99}
100
101static void spi100k_disable_clock(struct spi_master *master)
102{
103 unsigned int val;
104 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
105
106 /* disable SPI */
107 val = readw(spi100k->base + SPI_SETUP1);
108 val &= ~SPI_SETUP1_CLOCK_ENABLE;
109 writew(val, spi100k->base + SPI_SETUP1);
110}
111
112static void spi100k_write_data(struct spi_master *master, int len, int data)
113{
114 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
115
116 /* write 16-bit word, shifting 8-bit data if necessary */
117 if (len <= 8) {
118 data <<= 8;
119 len = 16;
120 }
121
122 spi100k_enable_clock(master);
123 writew(data , spi100k->base + SPI_TX_MSB);
124
125 writew(SPI_CTRL_SEN(0) |
126 SPI_CTRL_WORD_SIZE(len) |
127 SPI_CTRL_WR,
128 spi100k->base + SPI_CTRL);
129
130 /* Wait for bit ack send change */
131 while ((readw(spi100k->base + SPI_STATUS) & SPI_STATUS_WE) != SPI_STATUS_WE)
132 ;
133 udelay(1000);
134
135 spi100k_disable_clock(master);
136}
137
138static int spi100k_read_data(struct spi_master *master, int len)
139{
140 int dataH, dataL;
141 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
142
143 /* Always do at least 16 bits */
144 if (len <= 8)
145 len = 16;
146
147 spi100k_enable_clock(master);
148 writew(SPI_CTRL_SEN(0) |
149 SPI_CTRL_WORD_SIZE(len) |
150 SPI_CTRL_RD,
151 spi100k->base + SPI_CTRL);
152
153 while ((readw(spi100k->base + SPI_STATUS) & SPI_STATUS_RD) != SPI_STATUS_RD)
154 ;
155 udelay(1000);
156
157 dataL = readw(spi100k->base + SPI_RX_LSB);
158 dataH = readw(spi100k->base + SPI_RX_MSB);
159 spi100k_disable_clock(master);
160
161 return dataL;
162}
163
164static void spi100k_open(struct spi_master *master)
165{
166 /* get control of SPI */
167 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
168
169 writew(SPI_SETUP1_INT_READ_ENABLE |
170 SPI_SETUP1_INT_WRITE_ENABLE |
171 SPI_SETUP1_CLOCK_DIVISOR(0), spi100k->base + SPI_SETUP1);
172
173 /* configure clock and interrupts */
174 writew(SPI_SETUP2_ACTIVE_EDGE_FALLING |
175 SPI_SETUP2_NEGATIVE_LEVEL |
176 SPI_SETUP2_LEVEL_TRIGGER, spi100k->base + SPI_SETUP2);
177}
178
179static void omap1_spi100k_force_cs(struct omap1_spi100k *spi100k, int enable)
180{
181 if (enable)
182 writew(0x05fc, spi100k->base + SPI_CTRL);
183 else
184 writew(0x05fd, spi100k->base + SPI_CTRL);
185}
186
187static unsigned
188omap1_spi100k_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
189{
190 struct omap1_spi100k_cs *cs = spi->controller_state;
191 unsigned int count, c;
192 int word_len;
193
194 count = xfer->len;
195 c = count;
196 word_len = cs->word_len;
197
198 if (word_len <= 8) {
199 u8 *rx;
200 const u8 *tx;
201
202 rx = xfer->rx_buf;
203 tx = xfer->tx_buf;
204 do {
205 c -= 1;
206 if (xfer->tx_buf != NULL)
207 spi100k_write_data(spi->master, word_len, *tx++);
208 if (xfer->rx_buf != NULL)
209 *rx++ = spi100k_read_data(spi->master, word_len);
210 } while (c);
211 } else if (word_len <= 16) {
212 u16 *rx;
213 const u16 *tx;
214
215 rx = xfer->rx_buf;
216 tx = xfer->tx_buf;
217 do {
218 c -= 2;
219 if (xfer->tx_buf != NULL)
220 spi100k_write_data(spi->master, word_len, *tx++);
221 if (xfer->rx_buf != NULL)
222 *rx++ = spi100k_read_data(spi->master, word_len);
223 } while (c);
224 } else if (word_len <= 32) {
225 u32 *rx;
226 const u32 *tx;
227
228 rx = xfer->rx_buf;
229 tx = xfer->tx_buf;
230 do {
231 c -= 4;
232 if (xfer->tx_buf != NULL)
233 spi100k_write_data(spi->master, word_len, *tx);
234 if (xfer->rx_buf != NULL)
235 *rx = spi100k_read_data(spi->master, word_len);
236 } while (c);
237 }
238 return count - c;
239}
240
241/* called only when no transfer is active to this device */
242static int omap1_spi100k_setup_transfer(struct spi_device *spi,
243 struct spi_transfer *t)
244{
245 struct omap1_spi100k *spi100k = spi_master_get_devdata(spi->master);
246 struct omap1_spi100k_cs *cs = spi->controller_state;
247 u8 word_len;
248
249 if (t != NULL)
250 word_len = t->bits_per_word;
251 else
252 word_len = spi->bits_per_word;
253
254 if (spi->bits_per_word > 32)
255 return -EINVAL;
256 cs->word_len = word_len;
257
258 /* SPI init before transfer */
259 writew(0x3e , spi100k->base + SPI_SETUP1);
260 writew(0x00 , spi100k->base + SPI_STATUS);
261 writew(0x3e , spi100k->base + SPI_CTRL);
262
263 return 0;
264}
265
266/* the spi->mode bits understood by this driver: */
267#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH)
268
269static int omap1_spi100k_setup(struct spi_device *spi)
270{
271 int ret;
272 struct omap1_spi100k *spi100k;
273 struct omap1_spi100k_cs *cs = spi->controller_state;
274
275 spi100k = spi_master_get_devdata(spi->master);
276
277 if (!cs) {
278 cs = devm_kzalloc(&spi->dev, sizeof(*cs), GFP_KERNEL);
279 if (!cs)
280 return -ENOMEM;
281 cs->base = spi100k->base + spi->chip_select * 0x14;
282 spi->controller_state = cs;
283 }
284
285 spi100k_open(spi->master);
286
287 clk_prepare_enable(spi100k->ick);
288 clk_prepare_enable(spi100k->fck);
289
290 ret = omap1_spi100k_setup_transfer(spi, NULL);
291
292 clk_disable_unprepare(spi100k->ick);
293 clk_disable_unprepare(spi100k->fck);
294
295 return ret;
296}
297
298static int omap1_spi100k_transfer_one_message(struct spi_master *master,
299 struct spi_message *m)
300{
301 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
302 struct spi_device *spi = m->spi;
303 struct spi_transfer *t = NULL;
304 int cs_active = 0;
305 int status = 0;
306
307 list_for_each_entry(t, &m->transfers, transfer_list) {
308 if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
309 status = -EINVAL;
310 break;
311 }
312 status = omap1_spi100k_setup_transfer(spi, t);
313 if (status < 0)
314 break;
315
316 if (!cs_active) {
317 omap1_spi100k_force_cs(spi100k, 1);
318 cs_active = 1;
319 }
320
321 if (t->len) {
322 unsigned count;
323
324 count = omap1_spi100k_txrx_pio(spi, t);
325 m->actual_length += count;
326
327 if (count != t->len) {
328 status = -EIO;
329 break;
330 }
331 }
332
333 if (t->delay_usecs)
334 udelay(t->delay_usecs);
335
336 /* ignore the "leave it on after last xfer" hint */
337
338 if (t->cs_change) {
339 omap1_spi100k_force_cs(spi100k, 0);
340 cs_active = 0;
341 }
342 }
343
344 status = omap1_spi100k_setup_transfer(spi, NULL);
345
346 if (cs_active)
347 omap1_spi100k_force_cs(spi100k, 0);
348
349 m->status = status;
350
351 spi_finalize_current_message(master);
352
353 return status;
354}
355
356static int omap1_spi100k_probe(struct platform_device *pdev)
357{
358 struct spi_master *master;
359 struct omap1_spi100k *spi100k;
360 int status = 0;
361
362 if (!pdev->id)
363 return -EINVAL;
364
365 master = spi_alloc_master(&pdev->dev, sizeof(*spi100k));
366 if (master == NULL) {
367 dev_dbg(&pdev->dev, "master allocation failed\n");
368 return -ENOMEM;
369 }
370
371 if (pdev->id != -1)
372 master->bus_num = pdev->id;
373
374 master->setup = omap1_spi100k_setup;
375 master->transfer_one_message = omap1_spi100k_transfer_one_message;
376 master->num_chipselect = 2;
377 master->mode_bits = MODEBITS;
378 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
379 master->min_speed_hz = OMAP1_SPI100K_MAX_FREQ/(1<<16);
380 master->max_speed_hz = OMAP1_SPI100K_MAX_FREQ;
381 master->auto_runtime_pm = true;
382
383 spi100k = spi_master_get_devdata(master);
384
385 /*
386 * The memory region base address is taken as the platform_data.
387 * You should allocate this with ioremap() before initializing
388 * the SPI.
389 */
390 spi100k->base = (void __iomem *)dev_get_platdata(&pdev->dev);
391
392 spi100k->ick = devm_clk_get(&pdev->dev, "ick");
393 if (IS_ERR(spi100k->ick)) {
394 dev_dbg(&pdev->dev, "can't get spi100k_ick\n");
395 status = PTR_ERR(spi100k->ick);
396 goto err;
397 }
398
399 spi100k->fck = devm_clk_get(&pdev->dev, "fck");
400 if (IS_ERR(spi100k->fck)) {
401 dev_dbg(&pdev->dev, "can't get spi100k_fck\n");
402 status = PTR_ERR(spi100k->fck);
403 goto err;
404 }
405
406 status = clk_prepare_enable(spi100k->ick);
407 if (status != 0) {
408 dev_err(&pdev->dev, "failed to enable ick: %d\n", status);
409 goto err;
410 }
411
412 status = clk_prepare_enable(spi100k->fck);
413 if (status != 0) {
414 dev_err(&pdev->dev, "failed to enable fck: %d\n", status);
415 goto err_ick;
416 }
417
418 pm_runtime_enable(&pdev->dev);
419 pm_runtime_set_active(&pdev->dev);
420
421 status = devm_spi_register_master(&pdev->dev, master);
422 if (status < 0)
423 goto err_fck;
424
425 return status;
426
427err_fck:
428 clk_disable_unprepare(spi100k->fck);
429err_ick:
430 clk_disable_unprepare(spi100k->ick);
431err:
432 spi_master_put(master);
433 return status;
434}
435
436static int omap1_spi100k_remove(struct platform_device *pdev)
437{
438 struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
439 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
440
441 pm_runtime_disable(&pdev->dev);
442
443 clk_disable_unprepare(spi100k->fck);
444 clk_disable_unprepare(spi100k->ick);
445
446 return 0;
447}
448
449#ifdef CONFIG_PM
450static int omap1_spi100k_runtime_suspend(struct device *dev)
451{
452 struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
453 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
454
455 clk_disable_unprepare(spi100k->ick);
456 clk_disable_unprepare(spi100k->fck);
457
458 return 0;
459}
460
461static int omap1_spi100k_runtime_resume(struct device *dev)
462{
463 struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
464 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
465 int ret;
466
467 ret = clk_prepare_enable(spi100k->ick);
468 if (ret != 0) {
469 dev_err(dev, "Failed to enable ick: %d\n", ret);
470 return ret;
471 }
472
473 ret = clk_prepare_enable(spi100k->fck);
474 if (ret != 0) {
475 dev_err(dev, "Failed to enable fck: %d\n", ret);
476 clk_disable_unprepare(spi100k->ick);
477 return ret;
478 }
479
480 return 0;
481}
482#endif
483
484static const struct dev_pm_ops omap1_spi100k_pm = {
485 SET_RUNTIME_PM_OPS(omap1_spi100k_runtime_suspend,
486 omap1_spi100k_runtime_resume, NULL)
487};
488
489static struct platform_driver omap1_spi100k_driver = {
490 .driver = {
491 .name = "omap1_spi100k",
492 .pm = &omap1_spi100k_pm,
493 },
494 .probe = omap1_spi100k_probe,
495 .remove = omap1_spi100k_remove,
496};
497
498module_platform_driver(omap1_spi100k_driver);
499
500MODULE_DESCRIPTION("OMAP7xx SPI 100k controller driver");
501MODULE_AUTHOR("Fabrice Crohas <fcrohas@gmail.com>");
502MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * OMAP7xx SPI 100k controller driver
4 * Author: Fabrice Crohas <fcrohas@gmail.com>
5 * from original omap1_mcspi driver
6 *
7 * Copyright (C) 2005, 2006 Nokia Corporation
8 * Author: Samuel Ortiz <samuel.ortiz@nokia.com> and
9 * Juha Yrj�l� <juha.yrjola@nokia.com>
10 */
11#include <linux/kernel.h>
12#include <linux/init.h>
13#include <linux/interrupt.h>
14#include <linux/module.h>
15#include <linux/device.h>
16#include <linux/delay.h>
17#include <linux/platform_device.h>
18#include <linux/pm_runtime.h>
19#include <linux/err.h>
20#include <linux/clk.h>
21#include <linux/io.h>
22#include <linux/gpio.h>
23#include <linux/slab.h>
24
25#include <linux/spi/spi.h>
26
27#define OMAP1_SPI100K_MAX_FREQ 48000000
28
29#define ICR_SPITAS (OMAP7XX_ICR_BASE + 0x12)
30
31#define SPI_SETUP1 0x00
32#define SPI_SETUP2 0x02
33#define SPI_CTRL 0x04
34#define SPI_STATUS 0x06
35#define SPI_TX_LSB 0x08
36#define SPI_TX_MSB 0x0a
37#define SPI_RX_LSB 0x0c
38#define SPI_RX_MSB 0x0e
39
40#define SPI_SETUP1_INT_READ_ENABLE (1UL << 5)
41#define SPI_SETUP1_INT_WRITE_ENABLE (1UL << 4)
42#define SPI_SETUP1_CLOCK_DIVISOR(x) ((x) << 1)
43#define SPI_SETUP1_CLOCK_ENABLE (1UL << 0)
44
45#define SPI_SETUP2_ACTIVE_EDGE_FALLING (0UL << 0)
46#define SPI_SETUP2_ACTIVE_EDGE_RISING (1UL << 0)
47#define SPI_SETUP2_NEGATIVE_LEVEL (0UL << 5)
48#define SPI_SETUP2_POSITIVE_LEVEL (1UL << 5)
49#define SPI_SETUP2_LEVEL_TRIGGER (0UL << 10)
50#define SPI_SETUP2_EDGE_TRIGGER (1UL << 10)
51
52#define SPI_CTRL_SEN(x) ((x) << 7)
53#define SPI_CTRL_WORD_SIZE(x) (((x) - 1) << 2)
54#define SPI_CTRL_WR (1UL << 1)
55#define SPI_CTRL_RD (1UL << 0)
56
57#define SPI_STATUS_WE (1UL << 1)
58#define SPI_STATUS_RD (1UL << 0)
59
60/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
61 * cache operations; better heuristics consider wordsize and bitrate.
62 */
63#define DMA_MIN_BYTES 8
64
65#define SPI_RUNNING 0
66#define SPI_SHUTDOWN 1
67
68struct omap1_spi100k {
69 struct clk *ick;
70 struct clk *fck;
71
72 /* Virtual base address of the controller */
73 void __iomem *base;
74};
75
76struct omap1_spi100k_cs {
77 void __iomem *base;
78 int word_len;
79};
80
81static void spi100k_enable_clock(struct spi_master *master)
82{
83 unsigned int val;
84 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
85
86 /* enable SPI */
87 val = readw(spi100k->base + SPI_SETUP1);
88 val |= SPI_SETUP1_CLOCK_ENABLE;
89 writew(val, spi100k->base + SPI_SETUP1);
90}
91
92static void spi100k_disable_clock(struct spi_master *master)
93{
94 unsigned int val;
95 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
96
97 /* disable SPI */
98 val = readw(spi100k->base + SPI_SETUP1);
99 val &= ~SPI_SETUP1_CLOCK_ENABLE;
100 writew(val, spi100k->base + SPI_SETUP1);
101}
102
103static void spi100k_write_data(struct spi_master *master, int len, int data)
104{
105 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
106
107 /* write 16-bit word, shifting 8-bit data if necessary */
108 if (len <= 8) {
109 data <<= 8;
110 len = 16;
111 }
112
113 spi100k_enable_clock(master);
114 writew(data , spi100k->base + SPI_TX_MSB);
115
116 writew(SPI_CTRL_SEN(0) |
117 SPI_CTRL_WORD_SIZE(len) |
118 SPI_CTRL_WR,
119 spi100k->base + SPI_CTRL);
120
121 /* Wait for bit ack send change */
122 while ((readw(spi100k->base + SPI_STATUS) & SPI_STATUS_WE) != SPI_STATUS_WE)
123 ;
124 udelay(1000);
125
126 spi100k_disable_clock(master);
127}
128
129static int spi100k_read_data(struct spi_master *master, int len)
130{
131 int dataH, dataL;
132 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
133
134 /* Always do at least 16 bits */
135 if (len <= 8)
136 len = 16;
137
138 spi100k_enable_clock(master);
139 writew(SPI_CTRL_SEN(0) |
140 SPI_CTRL_WORD_SIZE(len) |
141 SPI_CTRL_RD,
142 spi100k->base + SPI_CTRL);
143
144 while ((readw(spi100k->base + SPI_STATUS) & SPI_STATUS_RD) != SPI_STATUS_RD)
145 ;
146 udelay(1000);
147
148 dataL = readw(spi100k->base + SPI_RX_LSB);
149 dataH = readw(spi100k->base + SPI_RX_MSB);
150 spi100k_disable_clock(master);
151
152 return dataL;
153}
154
155static void spi100k_open(struct spi_master *master)
156{
157 /* get control of SPI */
158 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
159
160 writew(SPI_SETUP1_INT_READ_ENABLE |
161 SPI_SETUP1_INT_WRITE_ENABLE |
162 SPI_SETUP1_CLOCK_DIVISOR(0), spi100k->base + SPI_SETUP1);
163
164 /* configure clock and interrupts */
165 writew(SPI_SETUP2_ACTIVE_EDGE_FALLING |
166 SPI_SETUP2_NEGATIVE_LEVEL |
167 SPI_SETUP2_LEVEL_TRIGGER, spi100k->base + SPI_SETUP2);
168}
169
170static void omap1_spi100k_force_cs(struct omap1_spi100k *spi100k, int enable)
171{
172 if (enable)
173 writew(0x05fc, spi100k->base + SPI_CTRL);
174 else
175 writew(0x05fd, spi100k->base + SPI_CTRL);
176}
177
178static unsigned
179omap1_spi100k_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
180{
181 struct omap1_spi100k_cs *cs = spi->controller_state;
182 unsigned int count, c;
183 int word_len;
184
185 count = xfer->len;
186 c = count;
187 word_len = cs->word_len;
188
189 if (word_len <= 8) {
190 u8 *rx;
191 const u8 *tx;
192
193 rx = xfer->rx_buf;
194 tx = xfer->tx_buf;
195 do {
196 c -= 1;
197 if (xfer->tx_buf != NULL)
198 spi100k_write_data(spi->master, word_len, *tx++);
199 if (xfer->rx_buf != NULL)
200 *rx++ = spi100k_read_data(spi->master, word_len);
201 } while (c);
202 } else if (word_len <= 16) {
203 u16 *rx;
204 const u16 *tx;
205
206 rx = xfer->rx_buf;
207 tx = xfer->tx_buf;
208 do {
209 c -= 2;
210 if (xfer->tx_buf != NULL)
211 spi100k_write_data(spi->master, word_len, *tx++);
212 if (xfer->rx_buf != NULL)
213 *rx++ = spi100k_read_data(spi->master, word_len);
214 } while (c);
215 } else if (word_len <= 32) {
216 u32 *rx;
217 const u32 *tx;
218
219 rx = xfer->rx_buf;
220 tx = xfer->tx_buf;
221 do {
222 c -= 4;
223 if (xfer->tx_buf != NULL)
224 spi100k_write_data(spi->master, word_len, *tx);
225 if (xfer->rx_buf != NULL)
226 *rx = spi100k_read_data(spi->master, word_len);
227 } while (c);
228 }
229 return count - c;
230}
231
232/* called only when no transfer is active to this device */
233static int omap1_spi100k_setup_transfer(struct spi_device *spi,
234 struct spi_transfer *t)
235{
236 struct omap1_spi100k *spi100k = spi_master_get_devdata(spi->master);
237 struct omap1_spi100k_cs *cs = spi->controller_state;
238 u8 word_len;
239
240 if (t != NULL)
241 word_len = t->bits_per_word;
242 else
243 word_len = spi->bits_per_word;
244
245 if (spi->bits_per_word > 32)
246 return -EINVAL;
247 cs->word_len = word_len;
248
249 /* SPI init before transfer */
250 writew(0x3e , spi100k->base + SPI_SETUP1);
251 writew(0x00 , spi100k->base + SPI_STATUS);
252 writew(0x3e , spi100k->base + SPI_CTRL);
253
254 return 0;
255}
256
257/* the spi->mode bits understood by this driver: */
258#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH)
259
260static int omap1_spi100k_setup(struct spi_device *spi)
261{
262 int ret;
263 struct omap1_spi100k *spi100k;
264 struct omap1_spi100k_cs *cs = spi->controller_state;
265
266 spi100k = spi_master_get_devdata(spi->master);
267
268 if (!cs) {
269 cs = devm_kzalloc(&spi->dev, sizeof(*cs), GFP_KERNEL);
270 if (!cs)
271 return -ENOMEM;
272 cs->base = spi100k->base + spi->chip_select * 0x14;
273 spi->controller_state = cs;
274 }
275
276 spi100k_open(spi->master);
277
278 clk_prepare_enable(spi100k->ick);
279 clk_prepare_enable(spi100k->fck);
280
281 ret = omap1_spi100k_setup_transfer(spi, NULL);
282
283 clk_disable_unprepare(spi100k->ick);
284 clk_disable_unprepare(spi100k->fck);
285
286 return ret;
287}
288
289static int omap1_spi100k_transfer_one_message(struct spi_master *master,
290 struct spi_message *m)
291{
292 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
293 struct spi_device *spi = m->spi;
294 struct spi_transfer *t = NULL;
295 int cs_active = 0;
296 int status = 0;
297
298 list_for_each_entry(t, &m->transfers, transfer_list) {
299 if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
300 status = -EINVAL;
301 break;
302 }
303 status = omap1_spi100k_setup_transfer(spi, t);
304 if (status < 0)
305 break;
306
307 if (!cs_active) {
308 omap1_spi100k_force_cs(spi100k, 1);
309 cs_active = 1;
310 }
311
312 if (t->len) {
313 unsigned count;
314
315 count = omap1_spi100k_txrx_pio(spi, t);
316 m->actual_length += count;
317
318 if (count != t->len) {
319 status = -EIO;
320 break;
321 }
322 }
323
324 if (t->delay_usecs)
325 udelay(t->delay_usecs);
326
327 /* ignore the "leave it on after last xfer" hint */
328
329 if (t->cs_change) {
330 omap1_spi100k_force_cs(spi100k, 0);
331 cs_active = 0;
332 }
333 }
334
335 status = omap1_spi100k_setup_transfer(spi, NULL);
336
337 if (cs_active)
338 omap1_spi100k_force_cs(spi100k, 0);
339
340 m->status = status;
341
342 spi_finalize_current_message(master);
343
344 return status;
345}
346
347static int omap1_spi100k_probe(struct platform_device *pdev)
348{
349 struct spi_master *master;
350 struct omap1_spi100k *spi100k;
351 int status = 0;
352
353 if (!pdev->id)
354 return -EINVAL;
355
356 master = spi_alloc_master(&pdev->dev, sizeof(*spi100k));
357 if (master == NULL) {
358 dev_dbg(&pdev->dev, "master allocation failed\n");
359 return -ENOMEM;
360 }
361
362 if (pdev->id != -1)
363 master->bus_num = pdev->id;
364
365 master->setup = omap1_spi100k_setup;
366 master->transfer_one_message = omap1_spi100k_transfer_one_message;
367 master->num_chipselect = 2;
368 master->mode_bits = MODEBITS;
369 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
370 master->min_speed_hz = OMAP1_SPI100K_MAX_FREQ/(1<<16);
371 master->max_speed_hz = OMAP1_SPI100K_MAX_FREQ;
372 master->auto_runtime_pm = true;
373
374 spi100k = spi_master_get_devdata(master);
375
376 /*
377 * The memory region base address is taken as the platform_data.
378 * You should allocate this with ioremap() before initializing
379 * the SPI.
380 */
381 spi100k->base = (void __iomem *)dev_get_platdata(&pdev->dev);
382
383 spi100k->ick = devm_clk_get(&pdev->dev, "ick");
384 if (IS_ERR(spi100k->ick)) {
385 dev_dbg(&pdev->dev, "can't get spi100k_ick\n");
386 status = PTR_ERR(spi100k->ick);
387 goto err;
388 }
389
390 spi100k->fck = devm_clk_get(&pdev->dev, "fck");
391 if (IS_ERR(spi100k->fck)) {
392 dev_dbg(&pdev->dev, "can't get spi100k_fck\n");
393 status = PTR_ERR(spi100k->fck);
394 goto err;
395 }
396
397 status = clk_prepare_enable(spi100k->ick);
398 if (status != 0) {
399 dev_err(&pdev->dev, "failed to enable ick: %d\n", status);
400 goto err;
401 }
402
403 status = clk_prepare_enable(spi100k->fck);
404 if (status != 0) {
405 dev_err(&pdev->dev, "failed to enable fck: %d\n", status);
406 goto err_ick;
407 }
408
409 pm_runtime_enable(&pdev->dev);
410 pm_runtime_set_active(&pdev->dev);
411
412 status = devm_spi_register_master(&pdev->dev, master);
413 if (status < 0)
414 goto err_fck;
415
416 return status;
417
418err_fck:
419 clk_disable_unprepare(spi100k->fck);
420err_ick:
421 clk_disable_unprepare(spi100k->ick);
422err:
423 spi_master_put(master);
424 return status;
425}
426
427static int omap1_spi100k_remove(struct platform_device *pdev)
428{
429 struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
430 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
431
432 pm_runtime_disable(&pdev->dev);
433
434 clk_disable_unprepare(spi100k->fck);
435 clk_disable_unprepare(spi100k->ick);
436
437 return 0;
438}
439
440#ifdef CONFIG_PM
441static int omap1_spi100k_runtime_suspend(struct device *dev)
442{
443 struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
444 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
445
446 clk_disable_unprepare(spi100k->ick);
447 clk_disable_unprepare(spi100k->fck);
448
449 return 0;
450}
451
452static int omap1_spi100k_runtime_resume(struct device *dev)
453{
454 struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
455 struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
456 int ret;
457
458 ret = clk_prepare_enable(spi100k->ick);
459 if (ret != 0) {
460 dev_err(dev, "Failed to enable ick: %d\n", ret);
461 return ret;
462 }
463
464 ret = clk_prepare_enable(spi100k->fck);
465 if (ret != 0) {
466 dev_err(dev, "Failed to enable fck: %d\n", ret);
467 clk_disable_unprepare(spi100k->ick);
468 return ret;
469 }
470
471 return 0;
472}
473#endif
474
475static const struct dev_pm_ops omap1_spi100k_pm = {
476 SET_RUNTIME_PM_OPS(omap1_spi100k_runtime_suspend,
477 omap1_spi100k_runtime_resume, NULL)
478};
479
480static struct platform_driver omap1_spi100k_driver = {
481 .driver = {
482 .name = "omap1_spi100k",
483 .pm = &omap1_spi100k_pm,
484 },
485 .probe = omap1_spi100k_probe,
486 .remove = omap1_spi100k_remove,
487};
488
489module_platform_driver(omap1_spi100k_driver);
490
491MODULE_DESCRIPTION("OMAP7xx SPI 100k controller driver");
492MODULE_AUTHOR("Fabrice Crohas <fcrohas@gmail.com>");
493MODULE_LICENSE("GPL");