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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> | |
31 | ||
1da177e4 LT |
32 | #include <asm/io.h> |
33 | #include <asm/irq.h> | |
a09e64fb RK |
34 | #include <mach/hardware.h> |
35 | #include <mach/ssp.h> | |
36 | #include <mach/pxa-regs.h> | |
37 | #include <mach/regs-ssp.h> | |
1da177e4 | 38 | |
8f1bf874 PS |
39 | #define TIMEOUT 100000 |
40 | ||
0cd61b68 | 41 | static irqreturn_t ssp_interrupt(int irq, void *dev_id) |
1da177e4 | 42 | { |
2a7057e3 | 43 | struct ssp_dev *dev = dev_id; |
3dcb00ea | 44 | struct ssp_device *ssp = dev->ssp; |
45 | unsigned int status; | |
1da177e4 | 46 | |
3dcb00ea | 47 | status = __raw_readl(ssp->mmio_base + SSSR); |
48 | __raw_writel(status, ssp->mmio_base + SSSR); | |
1da177e4 LT |
49 | |
50 | if (status & SSSR_ROR) | |
51 | printk(KERN_WARNING "SSP(%d): receiver overrun\n", dev->port); | |
52 | ||
53 | if (status & SSSR_TUR) | |
54 | printk(KERN_WARNING "SSP(%d): transmitter underrun\n", dev->port); | |
55 | ||
56 | if (status & SSSR_BCE) | |
57 | printk(KERN_WARNING "SSP(%d): bit count error\n", dev->port); | |
58 | ||
59 | return IRQ_HANDLED; | |
60 | } | |
61 | ||
62 | /** | |
63 | * ssp_write_word - write a word to the SSP port | |
64 | * @data: 32-bit, MSB justified data to write. | |
65 | * | |
66 | * Wait for a free entry in the SSP transmit FIFO, and write a data | |
67 | * word to the SSP port. | |
68 | * | |
69 | * The caller is expected to perform the necessary locking. | |
70 | * | |
71 | * Returns: | |
8f1bf874 | 72 | * %-ETIMEDOUT timeout occurred |
1da177e4 LT |
73 | * 0 success |
74 | */ | |
75 | int ssp_write_word(struct ssp_dev *dev, u32 data) | |
76 | { | |
3dcb00ea | 77 | struct ssp_device *ssp = dev->ssp; |
8f1bf874 PS |
78 | int timeout = TIMEOUT; |
79 | ||
3dcb00ea | 80 | while (!(__raw_readl(ssp->mmio_base + SSSR) & SSSR_TNF)) { |
8f1bf874 PS |
81 | if (!--timeout) |
82 | return -ETIMEDOUT; | |
1da177e4 | 83 | cpu_relax(); |
8f1bf874 | 84 | } |
1da177e4 | 85 | |
3dcb00ea | 86 | __raw_writel(data, ssp->mmio_base + SSDR); |
1da177e4 LT |
87 | |
88 | return 0; | |
89 | } | |
90 | ||
91 | /** | |
92 | * ssp_read_word - read a word from the SSP port | |
93 | * | |
94 | * Wait for a data word in the SSP receive FIFO, and return the | |
95 | * received data. Data is LSB justified. | |
96 | * | |
97 | * Note: Currently, if data is not expected to be received, this | |
98 | * function will wait for ever. | |
99 | * | |
100 | * The caller is expected to perform the necessary locking. | |
101 | * | |
102 | * Returns: | |
8f1bf874 | 103 | * %-ETIMEDOUT timeout occurred |
1da177e4 LT |
104 | * 32-bit data success |
105 | */ | |
8f1bf874 | 106 | int ssp_read_word(struct ssp_dev *dev, u32 *data) |
1da177e4 | 107 | { |
3dcb00ea | 108 | struct ssp_device *ssp = dev->ssp; |
8f1bf874 PS |
109 | int timeout = TIMEOUT; |
110 | ||
3dcb00ea | 111 | while (!(__raw_readl(ssp->mmio_base + SSSR) & SSSR_RNE)) { |
8f1bf874 PS |
112 | if (!--timeout) |
113 | return -ETIMEDOUT; | |
1da177e4 | 114 | cpu_relax(); |
8f1bf874 | 115 | } |
1da177e4 | 116 | |
3dcb00ea | 117 | *data = __raw_readl(ssp->mmio_base + SSDR); |
8f1bf874 | 118 | return 0; |
1da177e4 LT |
119 | } |
120 | ||
121 | /** | |
122 | * ssp_flush - flush the transmit and receive FIFOs | |
123 | * | |
124 | * Wait for the SSP to idle, and ensure that the receive FIFO | |
125 | * is empty. | |
126 | * | |
127 | * The caller is expected to perform the necessary locking. | |
128 | */ | |
8f1bf874 | 129 | int ssp_flush(struct ssp_dev *dev) |
1da177e4 | 130 | { |
3dcb00ea | 131 | struct ssp_device *ssp = dev->ssp; |
8f1bf874 PS |
132 | int timeout = TIMEOUT * 2; |
133 | ||
732ce160 | 134 | /* ensure TX FIFO is empty instead of not full */ |
135 | if (cpu_is_pxa3xx()) { | |
136 | while (__raw_readl(ssp->mmio_base + SSSR) & 0xf00) { | |
137 | if (!--timeout) | |
138 | return -ETIMEDOUT; | |
139 | cpu_relax(); | |
140 | } | |
141 | timeout = TIMEOUT * 2; | |
142 | } | |
143 | ||
1da177e4 | 144 | do { |
3dcb00ea | 145 | while (__raw_readl(ssp->mmio_base + SSSR) & SSSR_RNE) { |
8f1bf874 PS |
146 | if (!--timeout) |
147 | return -ETIMEDOUT; | |
3dcb00ea | 148 | (void)__raw_readl(ssp->mmio_base + SSDR); |
1da177e4 | 149 | } |
8f1bf874 PS |
150 | if (!--timeout) |
151 | return -ETIMEDOUT; | |
3dcb00ea | 152 | } while (__raw_readl(ssp->mmio_base + SSSR) & SSSR_BSY); |
8f1bf874 PS |
153 | |
154 | return 0; | |
1da177e4 LT |
155 | } |
156 | ||
157 | /** | |
158 | * ssp_enable - enable the SSP port | |
159 | * | |
160 | * Turn on the SSP port. | |
161 | */ | |
162 | void ssp_enable(struct ssp_dev *dev) | |
163 | { | |
3dcb00ea | 164 | struct ssp_device *ssp = dev->ssp; |
165 | uint32_t sscr0; | |
166 | ||
167 | sscr0 = __raw_readl(ssp->mmio_base + SSCR0); | |
168 | sscr0 |= SSCR0_SSE; | |
169 | __raw_writel(sscr0, ssp->mmio_base + SSCR0); | |
1da177e4 LT |
170 | } |
171 | ||
172 | /** | |
173 | * ssp_disable - shut down the SSP port | |
174 | * | |
175 | * Turn off the SSP port, optionally powering it down. | |
176 | */ | |
177 | void ssp_disable(struct ssp_dev *dev) | |
178 | { | |
3dcb00ea | 179 | struct ssp_device *ssp = dev->ssp; |
180 | uint32_t sscr0; | |
181 | ||
182 | sscr0 = __raw_readl(ssp->mmio_base + SSCR0); | |
183 | sscr0 &= ~SSCR0_SSE; | |
184 | __raw_writel(sscr0, ssp->mmio_base + SSCR0); | |
1da177e4 LT |
185 | } |
186 | ||
187 | /** | |
188 | * ssp_save_state - save the SSP configuration | |
189 | * @ssp: pointer to structure to save SSP configuration | |
190 | * | |
191 | * Save the configured SSP state for suspend. | |
192 | */ | |
3dcb00ea | 193 | void ssp_save_state(struct ssp_dev *dev, struct ssp_state *state) |
1da177e4 | 194 | { |
3dcb00ea | 195 | struct ssp_device *ssp = dev->ssp; |
196 | ||
197 | state->cr0 = __raw_readl(ssp->mmio_base + SSCR0); | |
198 | state->cr1 = __raw_readl(ssp->mmio_base + SSCR1); | |
199 | state->to = __raw_readl(ssp->mmio_base + SSTO); | |
200 | state->psp = __raw_readl(ssp->mmio_base + SSPSP); | |
1da177e4 | 201 | |
3dcb00ea | 202 | ssp_disable(dev); |
1da177e4 LT |
203 | } |
204 | ||
205 | /** | |
206 | * ssp_restore_state - restore a previously saved SSP configuration | |
207 | * @ssp: pointer to configuration saved by ssp_save_state | |
208 | * | |
209 | * Restore the SSP configuration saved previously by ssp_save_state. | |
210 | */ | |
3dcb00ea | 211 | void ssp_restore_state(struct ssp_dev *dev, struct ssp_state *state) |
1da177e4 | 212 | { |
3dcb00ea | 213 | struct ssp_device *ssp = dev->ssp; |
214 | uint32_t sssr = SSSR_ROR | SSSR_TUR | SSSR_BCE; | |
1da177e4 | 215 | |
3dcb00ea | 216 | __raw_writel(sssr, ssp->mmio_base + SSSR); |
1da177e4 | 217 | |
3dcb00ea | 218 | __raw_writel(state->cr0 & ~SSCR0_SSE, ssp->mmio_base + SSCR0); |
219 | __raw_writel(state->cr1, ssp->mmio_base + SSCR1); | |
220 | __raw_writel(state->to, ssp->mmio_base + SSTO); | |
221 | __raw_writel(state->psp, ssp->mmio_base + SSPSP); | |
222 | __raw_writel(state->cr0, ssp->mmio_base + SSCR0); | |
1da177e4 LT |
223 | } |
224 | ||
225 | /** | |
226 | * ssp_config - configure SSP port settings | |
227 | * @mode: port operating mode | |
228 | * @flags: port config flags | |
229 | * @psp_flags: port PSP config flags | |
230 | * @speed: port speed | |
231 | * | |
232 | * Port MUST be disabled by ssp_disable before making any config changes. | |
233 | */ | |
234 | int ssp_config(struct ssp_dev *dev, u32 mode, u32 flags, u32 psp_flags, u32 speed) | |
235 | { | |
3dcb00ea | 236 | struct ssp_device *ssp = dev->ssp; |
237 | ||
1da177e4 LT |
238 | dev->mode = mode; |
239 | dev->flags = flags; | |
240 | dev->psp_flags = psp_flags; | |
241 | dev->speed = speed; | |
242 | ||
243 | /* set up port type, speed, port settings */ | |
3dcb00ea | 244 | __raw_writel((dev->speed | dev->mode), ssp->mmio_base + SSCR0); |
245 | __raw_writel(dev->flags, ssp->mmio_base + SSCR1); | |
246 | __raw_writel(dev->psp_flags, ssp->mmio_base + SSPSP); | |
1da177e4 LT |
247 | |
248 | return 0; | |
249 | } | |
250 | ||
251 | /** | |
252 | * ssp_init - setup the SSP port | |
253 | * | |
254 | * initialise and claim resources for the SSP port. | |
255 | * | |
256 | * Returns: | |
257 | * %-ENODEV if the SSP port is unavailable | |
258 | * %-EBUSY if the resources are already in use | |
259 | * %0 on success | |
260 | */ | |
b216c018 | 261 | int ssp_init(struct ssp_dev *dev, u32 port, u32 init_flags) |
1da177e4 | 262 | { |
88286450 | 263 | struct ssp_device *ssp; |
b216c018 | 264 | int ret; |
1da177e4 | 265 | |
88286450 | 266 | ssp = ssp_request(port, "SSP"); |
267 | if (ssp == NULL) | |
1da177e4 LT |
268 | return -ENODEV; |
269 | ||
88286450 | 270 | dev->ssp = ssp; |
1da177e4 LT |
271 | dev->port = port; |
272 | ||
b216c018 LG |
273 | /* do we need to get irq */ |
274 | if (!(init_flags & SSP_NO_IRQ)) { | |
88286450 | 275 | ret = request_irq(ssp->irq, ssp_interrupt, |
b216c018 LG |
276 | 0, "SSP", dev); |
277 | if (ret) | |
278 | goto out_region; | |
88286450 | 279 | dev->irq = ssp->irq; |
b216c018 | 280 | } else |
bbae0203 | 281 | dev->irq = NO_IRQ; |
1da177e4 LT |
282 | |
283 | /* turn on SSP port clock */ | |
88286450 | 284 | clk_enable(ssp->clk); |
1da177e4 LT |
285 | return 0; |
286 | ||
287 | out_region: | |
88286450 | 288 | ssp_free(ssp); |
1da177e4 LT |
289 | return ret; |
290 | } | |
291 | ||
292 | /** | |
293 | * ssp_exit - undo the effects of ssp_init | |
294 | * | |
295 | * release and free resources for the SSP port. | |
296 | */ | |
297 | void ssp_exit(struct ssp_dev *dev) | |
298 | { | |
88286450 | 299 | struct ssp_device *ssp = dev->ssp; |
300 | ||
3dcb00ea | 301 | ssp_disable(dev); |
bbae0203 MB |
302 | if (dev->irq != NO_IRQ) |
303 | free_irq(dev->irq, dev); | |
88286450 | 304 | clk_disable(ssp->clk); |
305 | ssp_free(ssp); | |
306 | } | |
307 | ||
308 | static DEFINE_MUTEX(ssp_lock); | |
309 | static LIST_HEAD(ssp_list); | |
310 | ||
311 | struct ssp_device *ssp_request(int port, const char *label) | |
312 | { | |
313 | struct ssp_device *ssp = NULL; | |
314 | ||
315 | mutex_lock(&ssp_lock); | |
1da177e4 | 316 | |
88286450 | 317 | list_for_each_entry(ssp, &ssp_list, node) { |
318 | if (ssp->port_id == port && ssp->use_count == 0) { | |
319 | ssp->use_count++; | |
320 | ssp->label = label; | |
321 | break; | |
322 | } | |
1da177e4 LT |
323 | } |
324 | ||
88286450 | 325 | mutex_unlock(&ssp_lock); |
326 | ||
a4aff223 | 327 | if (&ssp->node == &ssp_list) |
88286450 | 328 | return NULL; |
329 | ||
330 | return ssp; | |
331 | } | |
332 | EXPORT_SYMBOL(ssp_request); | |
333 | ||
334 | void ssp_free(struct ssp_device *ssp) | |
335 | { | |
336 | mutex_lock(&ssp_lock); | |
337 | if (ssp->use_count) { | |
338 | ssp->use_count--; | |
339 | ssp->label = NULL; | |
340 | } else | |
341 | dev_err(&ssp->pdev->dev, "device already free\n"); | |
342 | mutex_unlock(&ssp_lock); | |
1da177e4 | 343 | } |
88286450 | 344 | EXPORT_SYMBOL(ssp_free); |
345 | ||
346 | static int __devinit ssp_probe(struct platform_device *pdev, int type) | |
347 | { | |
348 | struct resource *res; | |
349 | struct ssp_device *ssp; | |
350 | int ret = 0; | |
351 | ||
352 | ssp = kzalloc(sizeof(struct ssp_device), GFP_KERNEL); | |
353 | if (ssp == NULL) { | |
354 | dev_err(&pdev->dev, "failed to allocate memory"); | |
355 | return -ENOMEM; | |
356 | } | |
919dcb21 | 357 | ssp->pdev = pdev; |
88286450 | 358 | |
359 | ssp->clk = clk_get(&pdev->dev, "SSPCLK"); | |
360 | if (IS_ERR(ssp->clk)) { | |
361 | ret = PTR_ERR(ssp->clk); | |
362 | goto err_free; | |
363 | } | |
364 | ||
365 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
366 | if (res == NULL) { | |
367 | dev_err(&pdev->dev, "no memory resource defined\n"); | |
368 | ret = -ENODEV; | |
369 | goto err_free_clk; | |
370 | } | |
371 | ||
372 | res = request_mem_region(res->start, res->end - res->start + 1, | |
373 | pdev->name); | |
374 | if (res == NULL) { | |
375 | dev_err(&pdev->dev, "failed to request memory resource\n"); | |
376 | ret = -EBUSY; | |
377 | goto err_free_clk; | |
378 | } | |
379 | ||
380 | ssp->phys_base = res->start; | |
381 | ||
382 | ssp->mmio_base = ioremap(res->start, res->end - res->start + 1); | |
383 | if (ssp->mmio_base == NULL) { | |
384 | dev_err(&pdev->dev, "failed to ioremap() registers\n"); | |
385 | ret = -ENODEV; | |
386 | goto err_free_mem; | |
387 | } | |
388 | ||
389 | ssp->irq = platform_get_irq(pdev, 0); | |
390 | if (ssp->irq < 0) { | |
391 | dev_err(&pdev->dev, "no IRQ resource defined\n"); | |
392 | ret = -ENODEV; | |
393 | goto err_free_io; | |
394 | } | |
395 | ||
396 | res = platform_get_resource(pdev, IORESOURCE_DMA, 0); | |
397 | if (res == NULL) { | |
398 | dev_err(&pdev->dev, "no SSP RX DRCMR defined\n"); | |
399 | ret = -ENODEV; | |
400 | goto err_free_io; | |
401 | } | |
402 | ssp->drcmr_rx = res->start; | |
403 | ||
404 | res = platform_get_resource(pdev, IORESOURCE_DMA, 1); | |
405 | if (res == NULL) { | |
406 | dev_err(&pdev->dev, "no SSP TX DRCMR defined\n"); | |
407 | ret = -ENODEV; | |
408 | goto err_free_io; | |
409 | } | |
410 | ssp->drcmr_tx = res->start; | |
411 | ||
412 | /* PXA2xx/3xx SSP ports starts from 1 and the internal pdev->id | |
413 | * starts from 0, do a translation here | |
414 | */ | |
415 | ssp->port_id = pdev->id + 1; | |
416 | ssp->use_count = 0; | |
417 | ssp->type = type; | |
418 | ||
419 | mutex_lock(&ssp_lock); | |
420 | list_add(&ssp->node, &ssp_list); | |
421 | mutex_unlock(&ssp_lock); | |
422 | ||
423 | platform_set_drvdata(pdev, ssp); | |
424 | return 0; | |
425 | ||
426 | err_free_io: | |
427 | iounmap(ssp->mmio_base); | |
428 | err_free_mem: | |
429 | release_mem_region(res->start, res->end - res->start + 1); | |
430 | err_free_clk: | |
431 | clk_put(ssp->clk); | |
432 | err_free: | |
433 | kfree(ssp); | |
434 | return ret; | |
435 | } | |
436 | ||
437 | static int __devexit ssp_remove(struct platform_device *pdev) | |
438 | { | |
439 | struct resource *res; | |
440 | struct ssp_device *ssp; | |
441 | ||
442 | ssp = platform_get_drvdata(pdev); | |
443 | if (ssp == NULL) | |
444 | return -ENODEV; | |
445 | ||
446 | iounmap(ssp->mmio_base); | |
447 | ||
448 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
449 | release_mem_region(res->start, res->end - res->start + 1); | |
450 | ||
451 | clk_put(ssp->clk); | |
1da177e4 | 452 | |
88286450 | 453 | mutex_lock(&ssp_lock); |
454 | list_del(&ssp->node); | |
455 | mutex_unlock(&ssp_lock); | |
456 | ||
457 | kfree(ssp); | |
458 | return 0; | |
459 | } | |
460 | ||
461 | static int __devinit pxa25x_ssp_probe(struct platform_device *pdev) | |
462 | { | |
463 | return ssp_probe(pdev, PXA25x_SSP); | |
464 | } | |
465 | ||
466 | static int __devinit pxa25x_nssp_probe(struct platform_device *pdev) | |
467 | { | |
468 | return ssp_probe(pdev, PXA25x_NSSP); | |
469 | } | |
470 | ||
471 | static int __devinit pxa27x_ssp_probe(struct platform_device *pdev) | |
472 | { | |
473 | return ssp_probe(pdev, PXA27x_SSP); | |
474 | } | |
475 | ||
476 | static struct platform_driver pxa25x_ssp_driver = { | |
477 | .driver = { | |
478 | .name = "pxa25x-ssp", | |
479 | }, | |
480 | .probe = pxa25x_ssp_probe, | |
481 | .remove = __devexit_p(ssp_remove), | |
482 | }; | |
483 | ||
484 | static struct platform_driver pxa25x_nssp_driver = { | |
485 | .driver = { | |
486 | .name = "pxa25x-nssp", | |
487 | }, | |
488 | .probe = pxa25x_nssp_probe, | |
489 | .remove = __devexit_p(ssp_remove), | |
490 | }; | |
491 | ||
492 | static struct platform_driver pxa27x_ssp_driver = { | |
493 | .driver = { | |
494 | .name = "pxa27x-ssp", | |
495 | }, | |
496 | .probe = pxa27x_ssp_probe, | |
497 | .remove = __devexit_p(ssp_remove), | |
498 | }; | |
499 | ||
500 | static int __init pxa_ssp_init(void) | |
501 | { | |
502 | int ret = 0; | |
503 | ||
504 | ret = platform_driver_register(&pxa25x_ssp_driver); | |
505 | if (ret) { | |
506 | printk(KERN_ERR "failed to register pxa25x_ssp_driver"); | |
507 | return ret; | |
508 | } | |
509 | ||
510 | ret = platform_driver_register(&pxa25x_nssp_driver); | |
511 | if (ret) { | |
512 | printk(KERN_ERR "failed to register pxa25x_nssp_driver"); | |
513 | return ret; | |
514 | } | |
515 | ||
516 | ret = platform_driver_register(&pxa27x_ssp_driver); | |
517 | if (ret) { | |
518 | printk(KERN_ERR "failed to register pxa27x_ssp_driver"); | |
519 | return ret; | |
1da177e4 LT |
520 | } |
521 | ||
88286450 | 522 | return ret; |
523 | } | |
524 | ||
525 | static void __exit pxa_ssp_exit(void) | |
526 | { | |
527 | platform_driver_unregister(&pxa25x_ssp_driver); | |
528 | platform_driver_unregister(&pxa25x_nssp_driver); | |
529 | platform_driver_unregister(&pxa27x_ssp_driver); | |
1da177e4 LT |
530 | } |
531 | ||
cae05541 | 532 | arch_initcall(pxa_ssp_init); |
88286450 | 533 | module_exit(pxa_ssp_exit); |
1da177e4 LT |
534 | |
535 | EXPORT_SYMBOL(ssp_write_word); | |
536 | EXPORT_SYMBOL(ssp_read_word); | |
537 | EXPORT_SYMBOL(ssp_flush); | |
538 | EXPORT_SYMBOL(ssp_enable); | |
539 | EXPORT_SYMBOL(ssp_disable); | |
540 | EXPORT_SYMBOL(ssp_save_state); | |
541 | EXPORT_SYMBOL(ssp_restore_state); | |
542 | EXPORT_SYMBOL(ssp_init); | |
543 | EXPORT_SYMBOL(ssp_exit); | |
544 | EXPORT_SYMBOL(ssp_config); | |
545 | ||
546 | MODULE_DESCRIPTION("PXA SSP driver"); | |
547 | MODULE_AUTHOR("Liam Girdwood"); | |
548 | MODULE_LICENSE("GPL"); | |
549 |