1 /*
2  * linux/arch/arm/plat-omap/dmtimer.c
3  *
4  * OMAP Dual-Mode Timers
5  *
6  * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/
7  * Tarun Kanti DebBarma <tarun.kanti@ti.com>
8  * Thara Gopinath <thara@ti.com>
9  *
10  * dmtimer adaptation to platform_driver.
11  *
12  * Copyright (C) 2005 Nokia Corporation
13  * OMAP2 support by Juha Yrjola
14  * API improvements and OMAP2 clock framework support by Timo Teras
15  *
16  * Copyright (C) 2009 Texas Instruments
17  * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
18  *
19  * This program is free software; you can redistribute it and/or modify it
20  * under the terms of the GNU General Public License as published by the
21  * Free Software Foundation; either version 2 of the License, or (at your
22  * option) any later version.
23  *
24  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
25  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
26  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
27  * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29  * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  *
33  * You should have received a copy of the  GNU General Public License along
34  * with this program; if not, write  to the Free Software Foundation, Inc.,
35  * 675 Mass Ave, Cambridge, MA 02139, USA.
36  */
37 
38 #include <linux/module.h>
39 #include <linux/io.h>
40 #include <linux/slab.h>
41 #include <linux/err.h>
42 #include <linux/pm_runtime.h>
43 
44 #include <plat/dmtimer.h>
45 
46 static LIST_HEAD(omap_timer_list);
47 static DEFINE_SPINLOCK(dm_timer_lock);
48 
49 /**
50  * omap_dm_timer_read_reg - read timer registers in posted and non-posted mode
51  * @timer:      timer pointer over which read operation to perform
52  * @reg:        lowest byte holds the register offset
53  *
54  * The posted mode bit is encoded in reg. Note that in posted mode write
55  * pending bit must be checked. Otherwise a read of a non completed write
56  * will produce an error.
57  */
omap_dm_timer_read_reg(struct omap_dm_timer * timer,u32 reg)58 static inline u32 omap_dm_timer_read_reg(struct omap_dm_timer *timer, u32 reg)
59 {
60 	WARN_ON((reg & 0xff) < _OMAP_TIMER_WAKEUP_EN_OFFSET);
61 	return __omap_dm_timer_read(timer, reg, timer->posted);
62 }
63 
64 /**
65  * omap_dm_timer_write_reg - write timer registers in posted and non-posted mode
66  * @timer:      timer pointer over which write operation is to perform
67  * @reg:        lowest byte holds the register offset
68  * @value:      data to write into the register
69  *
70  * The posted mode bit is encoded in reg. Note that in posted mode the write
71  * pending bit must be checked. Otherwise a write on a register which has a
72  * pending write will be lost.
73  */
omap_dm_timer_write_reg(struct omap_dm_timer * timer,u32 reg,u32 value)74 static void omap_dm_timer_write_reg(struct omap_dm_timer *timer, u32 reg,
75 						u32 value)
76 {
77 	WARN_ON((reg & 0xff) < _OMAP_TIMER_WAKEUP_EN_OFFSET);
78 	__omap_dm_timer_write(timer, reg, value, timer->posted);
79 }
80 
omap_timer_restore_context(struct omap_dm_timer * timer)81 static void omap_timer_restore_context(struct omap_dm_timer *timer)
82 {
83 	omap_dm_timer_write_reg(timer, OMAP_TIMER_OCP_CFG_OFFSET,
84 				timer->context.tiocp_cfg);
85 	if (timer->revision > 1)
86 		__raw_writel(timer->context.tistat, timer->sys_stat);
87 
88 	__raw_writel(timer->context.tisr, timer->irq_stat);
89 	omap_dm_timer_write_reg(timer, OMAP_TIMER_WAKEUP_EN_REG,
90 				timer->context.twer);
91 	omap_dm_timer_write_reg(timer, OMAP_TIMER_COUNTER_REG,
92 				timer->context.tcrr);
93 	omap_dm_timer_write_reg(timer, OMAP_TIMER_LOAD_REG,
94 				timer->context.tldr);
95 	omap_dm_timer_write_reg(timer, OMAP_TIMER_MATCH_REG,
96 				timer->context.tmar);
97 	omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG,
98 				timer->context.tsicr);
99 	__raw_writel(timer->context.tier, timer->irq_ena);
100 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG,
101 				timer->context.tclr);
102 }
103 
omap_dm_timer_wait_for_reset(struct omap_dm_timer * timer)104 static void omap_dm_timer_wait_for_reset(struct omap_dm_timer *timer)
105 {
106 	int c;
107 
108 	if (!timer->sys_stat)
109 		return;
110 
111 	c = 0;
112 	while (!(__raw_readl(timer->sys_stat) & 1)) {
113 		c++;
114 		if (c > 100000) {
115 			printk(KERN_ERR "Timer failed to reset\n");
116 			return;
117 		}
118 	}
119 }
120 
omap_dm_timer_reset(struct omap_dm_timer * timer)121 static void omap_dm_timer_reset(struct omap_dm_timer *timer)
122 {
123 	omap_dm_timer_enable(timer);
124 	if (timer->pdev->id != 1) {
125 		omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG, 0x06);
126 		omap_dm_timer_wait_for_reset(timer);
127 	}
128 
129 	__omap_dm_timer_reset(timer, 0, 0);
130 	omap_dm_timer_disable(timer);
131 	timer->posted = 1;
132 }
133 
omap_dm_timer_prepare(struct omap_dm_timer * timer)134 int omap_dm_timer_prepare(struct omap_dm_timer *timer)
135 {
136 	struct dmtimer_platform_data *pdata = timer->pdev->dev.platform_data;
137 	int ret;
138 
139 	timer->fclk = clk_get(&timer->pdev->dev, "fck");
140 	if (WARN_ON_ONCE(IS_ERR_OR_NULL(timer->fclk))) {
141 		timer->fclk = NULL;
142 		dev_err(&timer->pdev->dev, ": No fclk handle.\n");
143 		return -EINVAL;
144 	}
145 
146 	if (pdata->needs_manual_reset)
147 		omap_dm_timer_reset(timer);
148 
149 	ret = omap_dm_timer_set_source(timer, OMAP_TIMER_SRC_32_KHZ);
150 
151 	timer->posted = 1;
152 	return ret;
153 }
154 
omap_dm_timer_request(void)155 struct omap_dm_timer *omap_dm_timer_request(void)
156 {
157 	struct omap_dm_timer *timer = NULL, *t;
158 	unsigned long flags;
159 	int ret = 0;
160 
161 	spin_lock_irqsave(&dm_timer_lock, flags);
162 	list_for_each_entry(t, &omap_timer_list, node) {
163 		if (t->reserved)
164 			continue;
165 
166 		timer = t;
167 		timer->reserved = 1;
168 		break;
169 	}
170 
171 	if (timer) {
172 		ret = omap_dm_timer_prepare(timer);
173 		if (ret) {
174 			timer->reserved = 0;
175 			timer = NULL;
176 		}
177 	}
178 	spin_unlock_irqrestore(&dm_timer_lock, flags);
179 
180 	if (!timer)
181 		pr_debug("%s: timer request failed!\n", __func__);
182 
183 	return timer;
184 }
185 EXPORT_SYMBOL_GPL(omap_dm_timer_request);
186 
omap_dm_timer_request_specific(int id)187 struct omap_dm_timer *omap_dm_timer_request_specific(int id)
188 {
189 	struct omap_dm_timer *timer = NULL, *t;
190 	unsigned long flags;
191 	int ret = 0;
192 
193 	spin_lock_irqsave(&dm_timer_lock, flags);
194 	list_for_each_entry(t, &omap_timer_list, node) {
195 		if (t->pdev->id == id && !t->reserved) {
196 			timer = t;
197 			timer->reserved = 1;
198 			break;
199 		}
200 	}
201 
202 	if (timer) {
203 		ret = omap_dm_timer_prepare(timer);
204 		if (ret) {
205 			timer->reserved = 0;
206 			timer = NULL;
207 		}
208 	}
209 	spin_unlock_irqrestore(&dm_timer_lock, flags);
210 
211 	if (!timer)
212 		pr_debug("%s: timer%d request failed!\n", __func__, id);
213 
214 	return timer;
215 }
216 EXPORT_SYMBOL_GPL(omap_dm_timer_request_specific);
217 
omap_dm_timer_free(struct omap_dm_timer * timer)218 int omap_dm_timer_free(struct omap_dm_timer *timer)
219 {
220 	if (unlikely(!timer))
221 		return -EINVAL;
222 
223 	clk_put(timer->fclk);
224 
225 	WARN_ON(!timer->reserved);
226 	timer->reserved = 0;
227 	return 0;
228 }
229 EXPORT_SYMBOL_GPL(omap_dm_timer_free);
230 
omap_dm_timer_enable(struct omap_dm_timer * timer)231 void omap_dm_timer_enable(struct omap_dm_timer *timer)
232 {
233 	pm_runtime_get_sync(&timer->pdev->dev);
234 }
235 EXPORT_SYMBOL_GPL(omap_dm_timer_enable);
236 
omap_dm_timer_disable(struct omap_dm_timer * timer)237 void omap_dm_timer_disable(struct omap_dm_timer *timer)
238 {
239 	pm_runtime_put(&timer->pdev->dev);
240 }
241 EXPORT_SYMBOL_GPL(omap_dm_timer_disable);
242 
omap_dm_timer_get_irq(struct omap_dm_timer * timer)243 int omap_dm_timer_get_irq(struct omap_dm_timer *timer)
244 {
245 	if (timer)
246 		return timer->irq;
247 	return -EINVAL;
248 }
249 EXPORT_SYMBOL_GPL(omap_dm_timer_get_irq);
250 
251 #if defined(CONFIG_ARCH_OMAP1)
252 
253 /**
254  * omap_dm_timer_modify_idlect_mask - Check if any running timers use ARMXOR
255  * @inputmask: current value of idlect mask
256  */
omap_dm_timer_modify_idlect_mask(__u32 inputmask)257 __u32 omap_dm_timer_modify_idlect_mask(__u32 inputmask)
258 {
259 	int i = 0;
260 	struct omap_dm_timer *timer = NULL;
261 	unsigned long flags;
262 
263 	/* If ARMXOR cannot be idled this function call is unnecessary */
264 	if (!(inputmask & (1 << 1)))
265 		return inputmask;
266 
267 	/* If any active timer is using ARMXOR return modified mask */
268 	spin_lock_irqsave(&dm_timer_lock, flags);
269 	list_for_each_entry(timer, &omap_timer_list, node) {
270 		u32 l;
271 
272 		l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
273 		if (l & OMAP_TIMER_CTRL_ST) {
274 			if (((omap_readl(MOD_CONF_CTRL_1) >> (i * 2)) & 0x03) == 0)
275 				inputmask &= ~(1 << 1);
276 			else
277 				inputmask &= ~(1 << 2);
278 		}
279 		i++;
280 	}
281 	spin_unlock_irqrestore(&dm_timer_lock, flags);
282 
283 	return inputmask;
284 }
285 EXPORT_SYMBOL_GPL(omap_dm_timer_modify_idlect_mask);
286 
287 #else
288 
omap_dm_timer_get_fclk(struct omap_dm_timer * timer)289 struct clk *omap_dm_timer_get_fclk(struct omap_dm_timer *timer)
290 {
291 	if (timer)
292 		return timer->fclk;
293 	return NULL;
294 }
295 EXPORT_SYMBOL_GPL(omap_dm_timer_get_fclk);
296 
omap_dm_timer_modify_idlect_mask(__u32 inputmask)297 __u32 omap_dm_timer_modify_idlect_mask(__u32 inputmask)
298 {
299 	BUG();
300 
301 	return 0;
302 }
303 EXPORT_SYMBOL_GPL(omap_dm_timer_modify_idlect_mask);
304 
305 #endif
306 
omap_dm_timer_trigger(struct omap_dm_timer * timer)307 int omap_dm_timer_trigger(struct omap_dm_timer *timer)
308 {
309 	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
310 		pr_err("%s: timer not available or enabled.\n", __func__);
311 		return -EINVAL;
312 	}
313 
314 	omap_dm_timer_write_reg(timer, OMAP_TIMER_TRIGGER_REG, 0);
315 	return 0;
316 }
317 EXPORT_SYMBOL_GPL(omap_dm_timer_trigger);
318 
omap_dm_timer_start(struct omap_dm_timer * timer)319 int omap_dm_timer_start(struct omap_dm_timer *timer)
320 {
321 	u32 l;
322 
323 	if (unlikely(!timer))
324 		return -EINVAL;
325 
326 	omap_dm_timer_enable(timer);
327 
328 	if (timer->loses_context) {
329 		u32 ctx_loss_cnt_after =
330 			timer->get_context_loss_count(&timer->pdev->dev);
331 		if (ctx_loss_cnt_after != timer->ctx_loss_count)
332 			omap_timer_restore_context(timer);
333 	}
334 
335 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
336 	if (!(l & OMAP_TIMER_CTRL_ST)) {
337 		l |= OMAP_TIMER_CTRL_ST;
338 		omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
339 	}
340 
341 	/* Save the context */
342 	timer->context.tclr = l;
343 	return 0;
344 }
345 EXPORT_SYMBOL_GPL(omap_dm_timer_start);
346 
omap_dm_timer_stop(struct omap_dm_timer * timer)347 int omap_dm_timer_stop(struct omap_dm_timer *timer)
348 {
349 	unsigned long rate = 0;
350 	struct dmtimer_platform_data *pdata = timer->pdev->dev.platform_data;
351 
352 	if (unlikely(!timer))
353 		return -EINVAL;
354 
355 	if (!pdata->needs_manual_reset)
356 		rate = clk_get_rate(timer->fclk);
357 
358 	__omap_dm_timer_stop(timer, timer->posted, rate);
359 
360 	return 0;
361 }
362 EXPORT_SYMBOL_GPL(omap_dm_timer_stop);
363 
omap_dm_timer_set_source(struct omap_dm_timer * timer,int source)364 int omap_dm_timer_set_source(struct omap_dm_timer *timer, int source)
365 {
366 	int ret;
367 	struct dmtimer_platform_data *pdata;
368 
369 	if (unlikely(!timer))
370 		return -EINVAL;
371 
372 	pdata = timer->pdev->dev.platform_data;
373 
374 	if (source < 0 || source >= 3)
375 		return -EINVAL;
376 
377 	ret = pdata->set_timer_src(timer->pdev, source);
378 
379 	return ret;
380 }
381 EXPORT_SYMBOL_GPL(omap_dm_timer_set_source);
382 
omap_dm_timer_set_load(struct omap_dm_timer * timer,int autoreload,unsigned int load)383 int omap_dm_timer_set_load(struct omap_dm_timer *timer, int autoreload,
384 			    unsigned int load)
385 {
386 	u32 l;
387 
388 	if (unlikely(!timer))
389 		return -EINVAL;
390 
391 	omap_dm_timer_enable(timer);
392 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
393 	if (autoreload)
394 		l |= OMAP_TIMER_CTRL_AR;
395 	else
396 		l &= ~OMAP_TIMER_CTRL_AR;
397 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
398 	omap_dm_timer_write_reg(timer, OMAP_TIMER_LOAD_REG, load);
399 
400 	omap_dm_timer_write_reg(timer, OMAP_TIMER_TRIGGER_REG, 0);
401 	/* Save the context */
402 	timer->context.tclr = l;
403 	timer->context.tldr = load;
404 	omap_dm_timer_disable(timer);
405 	return 0;
406 }
407 EXPORT_SYMBOL_GPL(omap_dm_timer_set_load);
408 
409 /* Optimized set_load which removes costly spin wait in timer_start */
omap_dm_timer_set_load_start(struct omap_dm_timer * timer,int autoreload,unsigned int load)410 int omap_dm_timer_set_load_start(struct omap_dm_timer *timer, int autoreload,
411                             unsigned int load)
412 {
413 	u32 l;
414 
415 	if (unlikely(!timer))
416 		return -EINVAL;
417 
418 	omap_dm_timer_enable(timer);
419 
420 	if (timer->loses_context) {
421 		u32 ctx_loss_cnt_after =
422 			timer->get_context_loss_count(&timer->pdev->dev);
423 		if (ctx_loss_cnt_after != timer->ctx_loss_count)
424 			omap_timer_restore_context(timer);
425 	}
426 
427 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
428 	if (autoreload) {
429 		l |= OMAP_TIMER_CTRL_AR;
430 		omap_dm_timer_write_reg(timer, OMAP_TIMER_LOAD_REG, load);
431 	} else {
432 		l &= ~OMAP_TIMER_CTRL_AR;
433 	}
434 	l |= OMAP_TIMER_CTRL_ST;
435 
436 	__omap_dm_timer_load_start(timer, l, load, timer->posted);
437 
438 	/* Save the context */
439 	timer->context.tclr = l;
440 	timer->context.tldr = load;
441 	timer->context.tcrr = load;
442 	return 0;
443 }
444 EXPORT_SYMBOL_GPL(omap_dm_timer_set_load_start);
445 
omap_dm_timer_set_match(struct omap_dm_timer * timer,int enable,unsigned int match)446 int omap_dm_timer_set_match(struct omap_dm_timer *timer, int enable,
447 			     unsigned int match)
448 {
449 	u32 l;
450 
451 	if (unlikely(!timer))
452 		return -EINVAL;
453 
454 	omap_dm_timer_enable(timer);
455 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
456 	if (enable)
457 		l |= OMAP_TIMER_CTRL_CE;
458 	else
459 		l &= ~OMAP_TIMER_CTRL_CE;
460 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
461 	omap_dm_timer_write_reg(timer, OMAP_TIMER_MATCH_REG, match);
462 
463 	/* Save the context */
464 	timer->context.tclr = l;
465 	timer->context.tmar = match;
466 	omap_dm_timer_disable(timer);
467 	return 0;
468 }
469 EXPORT_SYMBOL_GPL(omap_dm_timer_set_match);
470 
omap_dm_timer_set_pwm(struct omap_dm_timer * timer,int def_on,int toggle,int trigger)471 int omap_dm_timer_set_pwm(struct omap_dm_timer *timer, int def_on,
472 			   int toggle, int trigger)
473 {
474 	u32 l;
475 
476 	if (unlikely(!timer))
477 		return -EINVAL;
478 
479 	omap_dm_timer_enable(timer);
480 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
481 	l &= ~(OMAP_TIMER_CTRL_GPOCFG | OMAP_TIMER_CTRL_SCPWM |
482 	       OMAP_TIMER_CTRL_PT | (0x03 << 10));
483 	if (def_on)
484 		l |= OMAP_TIMER_CTRL_SCPWM;
485 	if (toggle)
486 		l |= OMAP_TIMER_CTRL_PT;
487 	l |= trigger << 10;
488 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
489 
490 	/* Save the context */
491 	timer->context.tclr = l;
492 	omap_dm_timer_disable(timer);
493 	return 0;
494 }
495 EXPORT_SYMBOL_GPL(omap_dm_timer_set_pwm);
496 
omap_dm_timer_set_prescaler(struct omap_dm_timer * timer,int prescaler)497 int omap_dm_timer_set_prescaler(struct omap_dm_timer *timer, int prescaler)
498 {
499 	u32 l;
500 
501 	if (unlikely(!timer))
502 		return -EINVAL;
503 
504 	omap_dm_timer_enable(timer);
505 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
506 	l &= ~(OMAP_TIMER_CTRL_PRE | (0x07 << 2));
507 	if (prescaler >= 0x00 && prescaler <= 0x07) {
508 		l |= OMAP_TIMER_CTRL_PRE;
509 		l |= prescaler << 2;
510 	}
511 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
512 
513 	/* Save the context */
514 	timer->context.tclr = l;
515 	omap_dm_timer_disable(timer);
516 	return 0;
517 }
518 EXPORT_SYMBOL_GPL(omap_dm_timer_set_prescaler);
519 
omap_dm_timer_set_int_enable(struct omap_dm_timer * timer,unsigned int value)520 int omap_dm_timer_set_int_enable(struct omap_dm_timer *timer,
521 				  unsigned int value)
522 {
523 	if (unlikely(!timer))
524 		return -EINVAL;
525 
526 	omap_dm_timer_enable(timer);
527 	__omap_dm_timer_int_enable(timer, value);
528 
529 	/* Save the context */
530 	timer->context.tier = value;
531 	timer->context.twer = value;
532 	omap_dm_timer_disable(timer);
533 	return 0;
534 }
535 EXPORT_SYMBOL_GPL(omap_dm_timer_set_int_enable);
536 
omap_dm_timer_read_status(struct omap_dm_timer * timer)537 unsigned int omap_dm_timer_read_status(struct omap_dm_timer *timer)
538 {
539 	unsigned int l;
540 
541 	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
542 		pr_err("%s: timer not available or enabled.\n", __func__);
543 		return 0;
544 	}
545 
546 	l = __raw_readl(timer->irq_stat);
547 
548 	return l;
549 }
550 EXPORT_SYMBOL_GPL(omap_dm_timer_read_status);
551 
omap_dm_timer_write_status(struct omap_dm_timer * timer,unsigned int value)552 int omap_dm_timer_write_status(struct omap_dm_timer *timer, unsigned int value)
553 {
554 	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev)))
555 		return -EINVAL;
556 
557 	__omap_dm_timer_write_status(timer, value);
558 	/* Save the context */
559 	timer->context.tisr = value;
560 	return 0;
561 }
562 EXPORT_SYMBOL_GPL(omap_dm_timer_write_status);
563 
omap_dm_timer_read_counter(struct omap_dm_timer * timer)564 unsigned int omap_dm_timer_read_counter(struct omap_dm_timer *timer)
565 {
566 	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
567 		pr_err("%s: timer not iavailable or enabled.\n", __func__);
568 		return 0;
569 	}
570 
571 	return __omap_dm_timer_read_counter(timer, timer->posted);
572 }
573 EXPORT_SYMBOL_GPL(omap_dm_timer_read_counter);
574 
omap_dm_timer_write_counter(struct omap_dm_timer * timer,unsigned int value)575 int omap_dm_timer_write_counter(struct omap_dm_timer *timer, unsigned int value)
576 {
577 	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
578 		pr_err("%s: timer not available or enabled.\n", __func__);
579 		return -EINVAL;
580 	}
581 
582 	omap_dm_timer_write_reg(timer, OMAP_TIMER_COUNTER_REG, value);
583 
584 	/* Save the context */
585 	timer->context.tcrr = value;
586 	return 0;
587 }
588 EXPORT_SYMBOL_GPL(omap_dm_timer_write_counter);
589 
omap_dm_timers_active(void)590 int omap_dm_timers_active(void)
591 {
592 	struct omap_dm_timer *timer;
593 
594 	list_for_each_entry(timer, &omap_timer_list, node) {
595 		if (!timer->reserved)
596 			continue;
597 
598 		if (omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG) &
599 		    OMAP_TIMER_CTRL_ST) {
600 			return 1;
601 		}
602 	}
603 	return 0;
604 }
605 EXPORT_SYMBOL_GPL(omap_dm_timers_active);
606 
607 /**
608  * omap_dm_timer_probe - probe function called for every registered device
609  * @pdev:	pointer to current timer platform device
610  *
611  * Called by driver framework at the end of device registration for all
612  * timer devices.
613  */
omap_dm_timer_probe(struct platform_device * pdev)614 static int __devinit omap_dm_timer_probe(struct platform_device *pdev)
615 {
616 	int ret;
617 	unsigned long flags;
618 	struct omap_dm_timer *timer;
619 	struct resource *mem, *irq, *ioarea;
620 	struct dmtimer_platform_data *pdata = pdev->dev.platform_data;
621 
622 	if (!pdata) {
623 		dev_err(&pdev->dev, "%s: no platform data.\n", __func__);
624 		return -ENODEV;
625 	}
626 
627 	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
628 	if (unlikely(!irq)) {
629 		dev_err(&pdev->dev, "%s: no IRQ resource.\n", __func__);
630 		return -ENODEV;
631 	}
632 
633 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
634 	if (unlikely(!mem)) {
635 		dev_err(&pdev->dev, "%s: no memory resource.\n", __func__);
636 		return -ENODEV;
637 	}
638 
639 	ioarea = request_mem_region(mem->start, resource_size(mem),
640 			pdev->name);
641 	if (!ioarea) {
642 		dev_err(&pdev->dev, "%s: region already claimed.\n", __func__);
643 		return -EBUSY;
644 	}
645 
646 	timer = kzalloc(sizeof(struct omap_dm_timer), GFP_KERNEL);
647 	if (!timer) {
648 		dev_err(&pdev->dev, "%s: no memory for omap_dm_timer.\n",
649 			__func__);
650 		ret = -ENOMEM;
651 		goto err_free_ioregion;
652 	}
653 
654 	timer->io_base = ioremap(mem->start, resource_size(mem));
655 	if (!timer->io_base) {
656 		dev_err(&pdev->dev, "%s: ioremap failed.\n", __func__);
657 		ret = -ENOMEM;
658 		goto err_free_mem;
659 	}
660 
661 	timer->id = pdev->id;
662 	timer->irq = irq->start;
663 	timer->reserved = pdata->reserved;
664 	timer->pdev = pdev;
665 	timer->loses_context = pdata->loses_context;
666 	timer->get_context_loss_count = pdata->get_context_loss_count;
667 
668 	/* Skip pm_runtime_enable for OMAP1 */
669 	if (!pdata->needs_manual_reset) {
670 		pm_runtime_enable(&pdev->dev);
671 		pm_runtime_irq_safe(&pdev->dev);
672 	}
673 
674 	if (!timer->reserved) {
675 		pm_runtime_get_sync(&pdev->dev);
676 		__omap_dm_timer_init_regs(timer);
677 		pm_runtime_put(&pdev->dev);
678 	}
679 
680 	/* add the timer element to the list */
681 	spin_lock_irqsave(&dm_timer_lock, flags);
682 	list_add_tail(&timer->node, &omap_timer_list);
683 	spin_unlock_irqrestore(&dm_timer_lock, flags);
684 
685 	dev_dbg(&pdev->dev, "Device Probed.\n");
686 
687 	return 0;
688 
689 err_free_mem:
690 	kfree(timer);
691 
692 err_free_ioregion:
693 	release_mem_region(mem->start, resource_size(mem));
694 
695 	return ret;
696 }
697 
698 /**
699  * omap_dm_timer_remove - cleanup a registered timer device
700  * @pdev:	pointer to current timer platform device
701  *
702  * Called by driver framework whenever a timer device is unregistered.
703  * In addition to freeing platform resources it also deletes the timer
704  * entry from the local list.
705  */
omap_dm_timer_remove(struct platform_device * pdev)706 static int __devexit omap_dm_timer_remove(struct platform_device *pdev)
707 {
708 	struct omap_dm_timer *timer;
709 	unsigned long flags;
710 	int ret = -EINVAL;
711 
712 	spin_lock_irqsave(&dm_timer_lock, flags);
713 	list_for_each_entry(timer, &omap_timer_list, node)
714 		if (timer->pdev->id == pdev->id) {
715 			list_del(&timer->node);
716 			kfree(timer);
717 			ret = 0;
718 			break;
719 		}
720 	spin_unlock_irqrestore(&dm_timer_lock, flags);
721 
722 	return ret;
723 }
724 
725 static struct platform_driver omap_dm_timer_driver = {
726 	.probe  = omap_dm_timer_probe,
727 	.remove = __devexit_p(omap_dm_timer_remove),
728 	.driver = {
729 		.name   = "omap_timer",
730 	},
731 };
732 
omap_dm_timer_driver_init(void)733 static int __init omap_dm_timer_driver_init(void)
734 {
735 	return platform_driver_register(&omap_dm_timer_driver);
736 }
737 
omap_dm_timer_driver_exit(void)738 static void __exit omap_dm_timer_driver_exit(void)
739 {
740 	platform_driver_unregister(&omap_dm_timer_driver);
741 }
742 
743 early_platform_init("earlytimer", &omap_dm_timer_driver);
744 module_init(omap_dm_timer_driver_init);
745 module_exit(omap_dm_timer_driver_exit);
746 
747 MODULE_DESCRIPTION("OMAP Dual-Mode Timer Driver");
748 MODULE_LICENSE("GPL");
749 MODULE_ALIAS("platform:" DRIVER_NAME);
750 MODULE_AUTHOR("Texas Instruments Inc");
751