Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/arch/arm/mach-pxa/ssp.c | |
3 | * | |
4 | * based on linux/arch/arm/mach-sa1100/ssp.c by Russell King | |
5 | * | |
6 | * Copyright (C) 2003 Russell King. | |
7 | * Copyright (C) 2003 Wolfson Microelectronics PLC | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify | |
10 | * it under the terms of the GNU General Public License version 2 as | |
11 | * published by the Free Software Foundation. | |
12 | * | |
13 | * PXA2xx SSP driver. This provides the generic core for simple | |
14 | * IO-based SSP applications and allows easy port setup for DMA access. | |
15 | * | |
16 | * Author: Liam Girdwood <liam.girdwood@wolfsonmicro.com> | |
1da177e4 LT |
17 | */ |
18 | ||
19 | #include <linux/module.h> | |
20 | #include <linux/kernel.h> | |
21 | #include <linux/sched.h> | |
22 | #include <linux/slab.h> | |
23 | #include <linux/errno.h> | |
24 | #include <linux/interrupt.h> | |
25 | #include <linux/ioport.h> | |
26 | #include <linux/init.h> | |
00431707 | 27 | #include <linux/mutex.h> |
88286450 | 28 | #include <linux/clk.h> |
29 | #include <linux/err.h> | |
30 | #include <linux/platform_device.h> | |
fced80c7 | 31 | #include <linux/io.h> |
88286450 | 32 | |
1da177e4 | 33 | #include <asm/irq.h> |
a09e64fb RK |
34 | #include <mach/hardware.h> |
35 | #include <mach/ssp.h> | |
a09e64fb | 36 | #include <mach/regs-ssp.h> |
1da177e4 | 37 | |
8f1bf874 PS |
38 | #define TIMEOUT 100000 |
39 | ||
0cd61b68 | 40 | static irqreturn_t ssp_interrupt(int irq, void *dev_id) |
1da177e4 | 41 | { |
2a7057e3 | 42 | struct ssp_dev *dev = dev_id; |
3dcb00ea | 43 | struct ssp_device *ssp = dev->ssp; |
44 | unsigned int status; | |
1da177e4 | 45 | |
3dcb00ea | 46 | status = __raw_readl(ssp->mmio_base + SSSR); |
47 | __raw_writel(status, ssp->mmio_base + SSSR); | |
1da177e4 LT |
48 | |
49 | if (status & SSSR_ROR) | |
50 | printk(KERN_WARNING "SSP(%d): receiver overrun\n", dev->port); | |
51 | ||
52 | if (status & SSSR_TUR) | |
53 | printk(KERN_WARNING "SSP(%d): transmitter underrun\n", dev->port); | |
54 | ||
55 | if (status & SSSR_BCE) | |
56 | printk(KERN_WARNING "SSP(%d): bit count error\n", dev->port); | |
57 | ||
58 | return IRQ_HANDLED; | |
59 | } | |
60 | ||
61 | /** | |
62 | * ssp_write_word - write a word to the SSP port | |
63 | * @data: 32-bit, MSB justified data to write. | |
64 | * | |
65 | * Wait for a free entry in the SSP transmit FIFO, and write a data | |
66 | * word to the SSP port. | |
67 | * | |
68 | * The caller is expected to perform the necessary locking. | |
69 | * | |
70 | * Returns: | |
8f1bf874 | 71 | * %-ETIMEDOUT timeout occurred |
1da177e4 LT |
72 | * 0 success |
73 | */ | |
74 | int ssp_write_word(struct ssp_dev *dev, u32 data) | |
75 | { | |
3dcb00ea | 76 | struct ssp_device *ssp = dev->ssp; |
8f1bf874 PS |
77 | int timeout = TIMEOUT; |
78 | ||
3dcb00ea | 79 | while (!(__raw_readl(ssp->mmio_base + SSSR) & SSSR_TNF)) { |
8f1bf874 PS |
80 | if (!--timeout) |
81 | return -ETIMEDOUT; | |
1da177e4 | 82 | cpu_relax(); |
8f1bf874 | 83 | } |
1da177e4 | 84 | |
3dcb00ea | 85 | __raw_writel(data, ssp->mmio_base + SSDR); |
1da177e4 LT |
86 | |
87 | return 0; | |
88 | } | |
89 | ||
90 | /** | |
91 | * ssp_read_word - read a word from the SSP port | |
92 | * | |
93 | * Wait for a data word in the SSP receive FIFO, and return the | |
94 | * received data. Data is LSB justified. | |
95 | * | |
96 | * Note: Currently, if data is not expected to be received, this | |
97 | * function will wait for ever. | |
98 | * | |
99 | * The caller is expected to perform the necessary locking. | |
100 | * | |
101 | * Returns: | |
8f1bf874 | 102 | * %-ETIMEDOUT timeout occurred |
1da177e4 LT |
103 | * 32-bit data success |
104 | */ | |
8f1bf874 | 105 | int ssp_read_word(struct ssp_dev *dev, u32 *data) |
1da177e4 | 106 | { |
3dcb00ea | 107 | struct ssp_device *ssp = dev->ssp; |
8f1bf874 PS |
108 | int timeout = TIMEOUT; |
109 | ||
3dcb00ea | 110 | while (!(__raw_readl(ssp->mmio_base + SSSR) & SSSR_RNE)) { |
8f1bf874 PS |
111 | if (!--timeout) |
112 | return -ETIMEDOUT; | |
1da177e4 | 113 | cpu_relax(); |
8f1bf874 | 114 | } |
1da177e4 | 115 | |
3dcb00ea | 116 | *data = __raw_readl(ssp->mmio_base + SSDR); |
8f1bf874 | 117 | return 0; |
1da177e4 LT |
118 | } |
119 | ||
120 | /** | |
121 | * ssp_flush - flush the transmit and receive FIFOs | |
122 | * | |
123 | * Wait for the SSP to idle, and ensure that the receive FIFO | |
124 | * is empty. | |
125 | * | |
126 | * The caller is expected to perform the necessary locking. | |
127 | */ | |
8f1bf874 | 128 | int ssp_flush(struct ssp_dev *dev) |
1da177e4 | 129 | { |
3dcb00ea | 130 | struct ssp_device *ssp = dev->ssp; |
8f1bf874 PS |
131 | int timeout = TIMEOUT * 2; |
132 | ||
732ce160 | 133 | /* ensure TX FIFO is empty instead of not full */ |
134 | if (cpu_is_pxa3xx()) { | |
135 | while (__raw_readl(ssp->mmio_base + SSSR) & 0xf00) { | |
136 | if (!--timeout) | |
137 | return -ETIMEDOUT; | |
138 | cpu_relax(); | |
139 | } | |
140 | timeout = TIMEOUT * 2; | |
141 | } | |
142 | ||
1da177e4 | 143 | do { |
3dcb00ea | 144 | while (__raw_readl(ssp->mmio_base + SSSR) & SSSR_RNE) { |
8f1bf874 PS |
145 | if (!--timeout) |
146 | return -ETIMEDOUT; | |
3dcb00ea | 147 | (void)__raw_readl(ssp->mmio_base + SSDR); |
1da177e4 | 148 | } |
8f1bf874 PS |
149 | if (!--timeout) |
150 | return -ETIMEDOUT; | |
3dcb00ea | 151 | } while (__raw_readl(ssp->mmio_base + SSSR) & SSSR_BSY); |
8f1bf874 PS |
152 | |
153 | return 0; | |
1da177e4 LT |
154 | } |
155 | ||
156 | /** | |
157 | * ssp_enable - enable the SSP port | |
158 | * | |
159 | * Turn on the SSP port. | |
160 | */ | |
161 | void ssp_enable(struct ssp_dev *dev) | |
162 | { | |
3dcb00ea | 163 | struct ssp_device *ssp = dev->ssp; |
164 | uint32_t sscr0; | |
165 | ||
166 | sscr0 = __raw_readl(ssp->mmio_base + SSCR0); | |
167 | sscr0 |= SSCR0_SSE; | |
168 | __raw_writel(sscr0, ssp->mmio_base + SSCR0); | |
1da177e4 LT |
169 | } |
170 | ||
171 | /** | |
172 | * ssp_disable - shut down the SSP port | |
173 | * | |
174 | * Turn off the SSP port, optionally powering it down. | |
175 | */ | |
176 | void ssp_disable(struct ssp_dev *dev) | |
177 | { | |
3dcb00ea | 178 | struct ssp_device *ssp = dev->ssp; |
179 | uint32_t sscr0; | |
180 | ||
181 | sscr0 = __raw_readl(ssp->mmio_base + SSCR0); | |
182 | sscr0 &= ~SSCR0_SSE; | |
183 | __raw_writel(sscr0, ssp->mmio_base + SSCR0); | |
1da177e4 LT |
184 | } |
185 | ||
186 | /** | |
187 | * ssp_save_state - save the SSP configuration | |
188 | * @ssp: pointer to structure to save SSP configuration | |
189 | * | |
190 | * Save the configured SSP state for suspend. | |
191 | */ | |
3dcb00ea | 192 | void ssp_save_state(struct ssp_dev *dev, struct ssp_state *state) |
1da177e4 | 193 | { |
3dcb00ea | 194 | struct ssp_device *ssp = dev->ssp; |
195 | ||
196 | state->cr0 = __raw_readl(ssp->mmio_base + SSCR0); | |
197 | state->cr1 = __raw_readl(ssp->mmio_base + SSCR1); | |
198 | state->to = __raw_readl(ssp->mmio_base + SSTO); | |
199 | state->psp = __raw_readl(ssp->mmio_base + SSPSP); | |
1da177e4 | 200 | |
3dcb00ea | 201 | ssp_disable(dev); |
1da177e4 LT |
202 | } |
203 | ||
204 | /** | |
205 | * ssp_restore_state - restore a previously saved SSP configuration | |
206 | * @ssp: pointer to configuration saved by ssp_save_state | |
207 | * | |
208 | * Restore the SSP configuration saved previously by ssp_save_state. | |
209 | */ | |
3dcb00ea | 210 | void ssp_restore_state(struct ssp_dev *dev, struct ssp_state *state) |
1da177e4 | 211 | { |
3dcb00ea | 212 | struct ssp_device *ssp = dev->ssp; |
213 | uint32_t sssr = SSSR_ROR | SSSR_TUR | SSSR_BCE; | |
1da177e4 | 214 | |
3dcb00ea | 215 | __raw_writel(sssr, ssp->mmio_base + SSSR); |
1da177e4 | 216 | |
3dcb00ea | 217 | __raw_writel(state->cr0 & ~SSCR0_SSE, ssp->mmio_base + SSCR0); |
218 | __raw_writel(state->cr1, ssp->mmio_base + SSCR1); | |
219 | __raw_writel(state->to, ssp->mmio_base + SSTO); | |
220 | __raw_writel(state->psp, ssp->mmio_base + SSPSP); | |
221 | __raw_writel(state->cr0, ssp->mmio_base + SSCR0); | |
1da177e4 LT |
222 | } |
223 | ||
224 | /** | |
225 | * ssp_config - configure SSP port settings | |
226 | * @mode: port operating mode | |
227 | * @flags: port config flags | |
228 | * @psp_flags: port PSP config flags | |
229 | * @speed: port speed | |
230 | * | |
231 | * Port MUST be disabled by ssp_disable before making any config changes. | |
232 | */ | |
233 | int ssp_config(struct ssp_dev *dev, u32 mode, u32 flags, u32 psp_flags, u32 speed) | |
234 | { | |
3dcb00ea | 235 | struct ssp_device *ssp = dev->ssp; |
236 | ||
1da177e4 LT |
237 | dev->mode = mode; |
238 | dev->flags = flags; | |
239 | dev->psp_flags = psp_flags; | |
240 | dev->speed = speed; | |
241 | ||
242 | /* set up port type, speed, port settings */ | |
3dcb00ea | 243 | __raw_writel((dev->speed | dev->mode), ssp->mmio_base + SSCR0); |
244 | __raw_writel(dev->flags, ssp->mmio_base + SSCR1); | |
245 | __raw_writel(dev->psp_flags, ssp->mmio_base + SSPSP); | |
1da177e4 LT |
246 | |
247 | return 0; | |
248 | } | |
249 | ||
250 | /** | |
251 | * ssp_init - setup the SSP port | |
252 | * | |
253 | * initialise and claim resources for the SSP port. | |
254 | * | |
255 | * Returns: | |
256 | * %-ENODEV if the SSP port is unavailable | |
257 | * %-EBUSY if the resources are already in use | |
258 | * %0 on success | |
259 | */ | |
b216c018 | 260 | int ssp_init(struct ssp_dev *dev, u32 port, u32 init_flags) |
1da177e4 | 261 | { |
88286450 | 262 | struct ssp_device *ssp; |
b216c018 | 263 | int ret; |
1da177e4 | 264 | |
88286450 | 265 | ssp = ssp_request(port, "SSP"); |
266 | if (ssp == NULL) | |
1da177e4 LT |
267 | return -ENODEV; |
268 | ||
88286450 | 269 | dev->ssp = ssp; |
1da177e4 LT |
270 | dev->port = port; |
271 | ||
b216c018 LG |
272 | /* do we need to get irq */ |
273 | if (!(init_flags & SSP_NO_IRQ)) { | |
88286450 | 274 | ret = request_irq(ssp->irq, ssp_interrupt, |
b216c018 LG |
275 | 0, "SSP", dev); |
276 | if (ret) | |
277 | goto out_region; | |
88286450 | 278 | dev->irq = ssp->irq; |
b216c018 | 279 | } else |
bbae0203 | 280 | dev->irq = NO_IRQ; |
1da177e4 LT |
281 | |
282 | /* turn on SSP port clock */ | |
88286450 | 283 | clk_enable(ssp->clk); |
1da177e4 LT |
284 | return 0; |
285 | ||
286 | out_region: | |
88286450 | 287 | ssp_free(ssp); |
1da177e4 LT |
288 | return ret; |
289 | } | |
290 | ||
291 | /** | |
292 | * ssp_exit - undo the effects of ssp_init | |
293 | * | |
294 | * release and free resources for the SSP port. | |
295 | */ | |
296 | void ssp_exit(struct ssp_dev *dev) | |
297 | { | |
88286450 | 298 | struct ssp_device *ssp = dev->ssp; |
299 | ||
3dcb00ea | 300 | ssp_disable(dev); |
bbae0203 MB |
301 | if (dev->irq != NO_IRQ) |
302 | free_irq(dev->irq, dev); | |
88286450 | 303 | clk_disable(ssp->clk); |
304 | ssp_free(ssp); | |
305 | } | |
306 | ||
307 | static DEFINE_MUTEX(ssp_lock); | |
308 | static LIST_HEAD(ssp_list); | |
309 | ||
310 | struct ssp_device *ssp_request(int port, const char *label) | |
311 | { | |
312 | struct ssp_device *ssp = NULL; | |
313 | ||
314 | mutex_lock(&ssp_lock); | |
1da177e4 | 315 | |
88286450 | 316 | list_for_each_entry(ssp, &ssp_list, node) { |
317 | if (ssp->port_id == port && ssp->use_count == 0) { | |
318 | ssp->use_count++; | |
319 | ssp->label = label; | |
320 | break; | |
321 | } | |
1da177e4 LT |
322 | } |
323 | ||
88286450 | 324 | mutex_unlock(&ssp_lock); |
325 | ||
a4aff223 | 326 | if (&ssp->node == &ssp_list) |
88286450 | 327 | return NULL; |
328 | ||
329 | return ssp; | |
330 | } | |
331 | EXPORT_SYMBOL(ssp_request); | |
332 | ||
333 | void ssp_free(struct ssp_device *ssp) | |
334 | { | |
335 | mutex_lock(&ssp_lock); | |
336 | if (ssp->use_count) { | |
337 | ssp->use_count--; | |
338 | ssp->label = NULL; | |
339 | } else | |
340 | dev_err(&ssp->pdev->dev, "device already free\n"); | |
341 | mutex_unlock(&ssp_lock); | |
1da177e4 | 342 | } |
88286450 | 343 | EXPORT_SYMBOL(ssp_free); |
344 | ||
345 | static int __devinit ssp_probe(struct platform_device *pdev, int type) | |
346 | { | |
347 | struct resource *res; | |
348 | struct ssp_device *ssp; | |
349 | int ret = 0; | |
350 | ||
351 | ssp = kzalloc(sizeof(struct ssp_device), GFP_KERNEL); | |
352 | if (ssp == NULL) { | |
353 | dev_err(&pdev->dev, "failed to allocate memory"); | |
354 | return -ENOMEM; | |
355 | } | |
919dcb21 | 356 | ssp->pdev = pdev; |
88286450 | 357 | |
e0d8b13a | 358 | ssp->clk = clk_get(&pdev->dev, NULL); |
88286450 | 359 | if (IS_ERR(ssp->clk)) { |
360 | ret = PTR_ERR(ssp->clk); | |
361 | goto err_free; | |
362 | } | |
363 | ||
364 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
365 | if (res == NULL) { | |
366 | dev_err(&pdev->dev, "no memory resource defined\n"); | |
367 | ret = -ENODEV; | |
368 | goto err_free_clk; | |
369 | } | |
370 | ||
371 | res = request_mem_region(res->start, res->end - res->start + 1, | |
372 | pdev->name); | |
373 | if (res == NULL) { | |
374 | dev_err(&pdev->dev, "failed to request memory resource\n"); | |
375 | ret = -EBUSY; | |
376 | goto err_free_clk; | |
377 | } | |
378 | ||
379 | ssp->phys_base = res->start; | |
380 | ||
381 | ssp->mmio_base = ioremap(res->start, res->end - res->start + 1); | |
382 | if (ssp->mmio_base == NULL) { | |
383 | dev_err(&pdev->dev, "failed to ioremap() registers\n"); | |
384 | ret = -ENODEV; | |
385 | goto err_free_mem; | |
386 | } | |
387 | ||
388 | ssp->irq = platform_get_irq(pdev, 0); | |
389 | if (ssp->irq < 0) { | |
390 | dev_err(&pdev->dev, "no IRQ resource defined\n"); | |
391 | ret = -ENODEV; | |
392 | goto err_free_io; | |
393 | } | |
394 | ||
395 | res = platform_get_resource(pdev, IORESOURCE_DMA, 0); | |
396 | if (res == NULL) { | |
397 | dev_err(&pdev->dev, "no SSP RX DRCMR defined\n"); | |
398 | ret = -ENODEV; | |
399 | goto err_free_io; | |
400 | } | |
401 | ssp->drcmr_rx = res->start; | |
402 | ||
403 | res = platform_get_resource(pdev, IORESOURCE_DMA, 1); | |
404 | if (res == NULL) { | |
405 | dev_err(&pdev->dev, "no SSP TX DRCMR defined\n"); | |
406 | ret = -ENODEV; | |
407 | goto err_free_io; | |
408 | } | |
409 | ssp->drcmr_tx = res->start; | |
410 | ||
411 | /* PXA2xx/3xx SSP ports starts from 1 and the internal pdev->id | |
412 | * starts from 0, do a translation here | |
413 | */ | |
414 | ssp->port_id = pdev->id + 1; | |
415 | ssp->use_count = 0; | |
416 | ssp->type = type; | |
417 | ||
418 | mutex_lock(&ssp_lock); | |
419 | list_add(&ssp->node, &ssp_list); | |
420 | mutex_unlock(&ssp_lock); | |
421 | ||
422 | platform_set_drvdata(pdev, ssp); | |
423 | return 0; | |
424 | ||
425 | err_free_io: | |
426 | iounmap(ssp->mmio_base); | |
427 | err_free_mem: | |
428 | release_mem_region(res->start, res->end - res->start + 1); | |
429 | err_free_clk: | |
430 | clk_put(ssp->clk); | |
431 | err_free: | |
432 | kfree(ssp); | |
433 | return ret; | |
434 | } | |
435 | ||
436 | static int __devexit ssp_remove(struct platform_device *pdev) | |
437 | { | |
438 | struct resource *res; | |
439 | struct ssp_device *ssp; | |
440 | ||
441 | ssp = platform_get_drvdata(pdev); | |
442 | if (ssp == NULL) | |
443 | return -ENODEV; | |
444 | ||
445 | iounmap(ssp->mmio_base); | |
446 | ||
447 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
448 | release_mem_region(res->start, res->end - res->start + 1); | |
449 | ||
450 | clk_put(ssp->clk); | |
1da177e4 | 451 | |
88286450 | 452 | mutex_lock(&ssp_lock); |
453 | list_del(&ssp->node); | |
454 | mutex_unlock(&ssp_lock); | |
455 | ||
456 | kfree(ssp); | |
457 | return 0; | |
458 | } | |
459 | ||
460 | static int __devinit pxa25x_ssp_probe(struct platform_device *pdev) | |
461 | { | |
462 | return ssp_probe(pdev, PXA25x_SSP); | |
463 | } | |
464 | ||
465 | static int __devinit pxa25x_nssp_probe(struct platform_device *pdev) | |
466 | { | |
467 | return ssp_probe(pdev, PXA25x_NSSP); | |
468 | } | |
469 | ||
470 | static int __devinit pxa27x_ssp_probe(struct platform_device *pdev) | |
471 | { | |
472 | return ssp_probe(pdev, PXA27x_SSP); | |
473 | } | |
474 | ||
475 | static struct platform_driver pxa25x_ssp_driver = { | |
476 | .driver = { | |
477 | .name = "pxa25x-ssp", | |
478 | }, | |
479 | .probe = pxa25x_ssp_probe, | |
480 | .remove = __devexit_p(ssp_remove), | |
481 | }; | |
482 | ||
483 | static struct platform_driver pxa25x_nssp_driver = { | |
484 | .driver = { | |
485 | .name = "pxa25x-nssp", | |
486 | }, | |
487 | .probe = pxa25x_nssp_probe, | |
488 | .remove = __devexit_p(ssp_remove), | |
489 | }; | |
490 | ||
491 | static struct platform_driver pxa27x_ssp_driver = { | |
492 | .driver = { | |
493 | .name = "pxa27x-ssp", | |
494 | }, | |
495 | .probe = pxa27x_ssp_probe, | |
496 | .remove = __devexit_p(ssp_remove), | |
497 | }; | |
498 | ||
499 | static int __init pxa_ssp_init(void) | |
500 | { | |
501 | int ret = 0; | |
502 | ||
503 | ret = platform_driver_register(&pxa25x_ssp_driver); | |
504 | if (ret) { | |
505 | printk(KERN_ERR "failed to register pxa25x_ssp_driver"); | |
506 | return ret; | |
507 | } | |
508 | ||
509 | ret = platform_driver_register(&pxa25x_nssp_driver); | |
510 | if (ret) { | |
511 | printk(KERN_ERR "failed to register pxa25x_nssp_driver"); | |
512 | return ret; | |
513 | } | |
514 | ||
515 | ret = platform_driver_register(&pxa27x_ssp_driver); | |
516 | if (ret) { | |
517 | printk(KERN_ERR "failed to register pxa27x_ssp_driver"); | |
518 | return ret; | |
1da177e4 LT |
519 | } |
520 | ||
88286450 | 521 | return ret; |
522 | } | |
523 | ||
524 | static void __exit pxa_ssp_exit(void) | |
525 | { | |
526 | platform_driver_unregister(&pxa25x_ssp_driver); | |
527 | platform_driver_unregister(&pxa25x_nssp_driver); | |
528 | platform_driver_unregister(&pxa27x_ssp_driver); | |
1da177e4 LT |
529 | } |
530 | ||
cae05541 | 531 | arch_initcall(pxa_ssp_init); |
88286450 | 532 | module_exit(pxa_ssp_exit); |
1da177e4 LT |
533 | |
534 | EXPORT_SYMBOL(ssp_write_word); | |
535 | EXPORT_SYMBOL(ssp_read_word); | |
536 | EXPORT_SYMBOL(ssp_flush); | |
537 | EXPORT_SYMBOL(ssp_enable); | |
538 | EXPORT_SYMBOL(ssp_disable); | |
539 | EXPORT_SYMBOL(ssp_save_state); | |
540 | EXPORT_SYMBOL(ssp_restore_state); | |
541 | EXPORT_SYMBOL(ssp_init); | |
542 | EXPORT_SYMBOL(ssp_exit); | |
543 | EXPORT_SYMBOL(ssp_config); | |
544 | ||
545 | MODULE_DESCRIPTION("PXA SSP driver"); | |
546 | MODULE_AUTHOR("Liam Girdwood"); | |
547 | MODULE_LICENSE("GPL"); | |
548 |