1 // SPDX-License-Identifier: GPL-2.0-only
3  * drivers/rtc/rtc-spear.c
6  * Rajeev Kumar<rajeev-[email protected]>
85 static inline void spear_rtc_clear_interrupt(struct spear_rtc_config *config)  in spear_rtc_clear_interrupt()  argument
90 	spin_lock_irqsave(&config->lock, flags);  in spear_rtc_clear_interrupt()
91 	val = readl(config->ioaddr + STATUS_REG);  in spear_rtc_clear_interrupt()
93 	writel(val, config->ioaddr + STATUS_REG);  in spear_rtc_clear_interrupt()
94 	spin_unlock_irqrestore(&config->lock, flags);  in spear_rtc_clear_interrupt()
97 static inline void spear_rtc_enable_interrupt(struct spear_rtc_config *config)  in spear_rtc_enable_interrupt()  argument
101 	val = readl(config->ioaddr + CTRL_REG);  in spear_rtc_enable_interrupt()
103 		spear_rtc_clear_interrupt(config);  in spear_rtc_enable_interrupt()
105 		writel(val, config->ioaddr + CTRL_REG);  in spear_rtc_enable_interrupt()
109 static inline void spear_rtc_disable_interrupt(struct spear_rtc_config *config)  in spear_rtc_disable_interrupt()  argument
113 	val = readl(config->ioaddr + CTRL_REG);  in spear_rtc_disable_interrupt()
116 		writel(val, config->ioaddr + CTRL_REG);  in spear_rtc_disable_interrupt()
120 static inline int is_write_complete(struct spear_rtc_config *config)  in is_write_complete()  argument
125 	spin_lock_irqsave(&config->lock, flags);  in is_write_complete()
126 	if ((readl(config->ioaddr + STATUS_REG)) & STATUS_FAIL)  in is_write_complete()
127 		ret = -EIO;  in is_write_complete()
128 	spin_unlock_irqrestore(&config->lock, flags);  in is_write_complete()
133 static void rtc_wait_not_busy(struct spear_rtc_config *config)  in rtc_wait_not_busy()  argument
140 		spin_lock_irqsave(&config->lock, flags);  in rtc_wait_not_busy()
141 		status = readl(config->ioaddr + STATUS_REG);  in rtc_wait_not_busy()
142 		spin_unlock_irqrestore(&config->lock, flags);  in rtc_wait_not_busy()
150 static irqreturn_t spear_rtc_irq(int irq, void *dev_id)  in spear_rtc_irq()
152 	struct spear_rtc_config *config = dev_id;  in spear_rtc_irq()  local
156 	spin_lock(&config->lock);  in spear_rtc_irq()
157 	irq_data = readl(config->ioaddr + STATUS_REG);  in spear_rtc_irq()
158 	spin_unlock(&config->lock);  in spear_rtc_irq()
161 		spear_rtc_clear_interrupt(config);  in spear_rtc_irq()
163 		rtc_update_irq(config->rtc, 1, events);  in spear_rtc_irq()
170 static void tm2bcd(struct rtc_time *tm)  in tm2bcd()
172 	tm->tm_sec = bin2bcd(tm->tm_sec);  in tm2bcd()
173 	tm->tm_min = bin2bcd(tm->tm_min);  in tm2bcd()
174 	tm->tm_hour = bin2bcd(tm->tm_hour);  in tm2bcd()
175 	tm->tm_mday = bin2bcd(tm->tm_mday);  in tm2bcd()
176 	tm->tm_mon = bin2bcd(tm->tm_mon + 1);  in tm2bcd()
177 	tm->tm_year = bin2bcd(tm->tm_year);  in tm2bcd()
180 static void bcd2tm(struct rtc_time *tm)  in bcd2tm()
182 	tm->tm_sec = bcd2bin(tm->tm_sec);  in bcd2tm()
183 	tm->tm_min = bcd2bin(tm->tm_min);  in bcd2tm()
184 	tm->tm_hour = bcd2bin(tm->tm_hour);  in bcd2tm()
185 	tm->tm_mday = bcd2bin(tm->tm_mday);  in bcd2tm()
186 	tm->tm_mon = bcd2bin(tm->tm_mon) - 1;  in bcd2tm()
188 	tm->tm_year = bcd2bin(tm->tm_year);  in bcd2tm()
192  * spear_rtc_read_time - set the time
197  * otherwise -ve error is returned.
199 static int spear_rtc_read_time(struct device *dev, struct rtc_time *tm)  in spear_rtc_read_time()
201 	struct spear_rtc_config *config = dev_get_drvdata(dev);  in spear_rtc_read_time()  local
205 	rtc_wait_not_busy(config);  in spear_rtc_read_time()
208 		time = readl(config->ioaddr + TIME_REG);  in spear_rtc_read_time()
209 		date = readl(config->ioaddr + DATE_REG);  in spear_rtc_read_time()
210 	} while (time == readl(config->ioaddr + TIME_REG));  in spear_rtc_read_time()
211 	tm->tm_sec = (time >> SECOND_SHIFT) & SECOND_MASK;  in spear_rtc_read_time()
212 	tm->tm_min = (time >> MINUTE_SHIFT) & MIN_MASK;  in spear_rtc_read_time()
213 	tm->tm_hour = (time >> HOUR_SHIFT) & HOUR_MASK;  in spear_rtc_read_time()
214 	tm->tm_mday = (date >> MDAY_SHIFT) & DAY_MASK;  in spear_rtc_read_time()
215 	tm->tm_mon = (date >> MONTH_SHIFT) & MONTH_MASK;  in spear_rtc_read_time()
216 	tm->tm_year = (date >> YEAR_SHIFT) & YEAR_MASK;  in spear_rtc_read_time()
223  * spear_rtc_set_time - set the time
228  * otherwise -ve error is returned.
230 static int spear_rtc_set_time(struct device *dev, struct rtc_time *tm)  in spear_rtc_set_time()
232 	struct spear_rtc_config *config = dev_get_drvdata(dev);  in spear_rtc_set_time()  local
237 	rtc_wait_not_busy(config);  in spear_rtc_set_time()
238 	time = (tm->tm_sec << SECOND_SHIFT) | (tm->tm_min << MINUTE_SHIFT) |  in spear_rtc_set_time()
239 		(tm->tm_hour << HOUR_SHIFT);  in spear_rtc_set_time()
240 	date = (tm->tm_mday << MDAY_SHIFT) | (tm->tm_mon << MONTH_SHIFT) |  in spear_rtc_set_time()
241 		(tm->tm_year << YEAR_SHIFT);  in spear_rtc_set_time()
242 	writel(time, config->ioaddr + TIME_REG);  in spear_rtc_set_time()
243 	writel(date, config->ioaddr + DATE_REG);  in spear_rtc_set_time()
245 	return is_write_complete(config);  in spear_rtc_set_time()
249  * spear_rtc_read_alarm - read the alarm time
254  * otherwise -ve error is returned.
256 static int spear_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)  in spear_rtc_read_alarm()
258 	struct spear_rtc_config *config = dev_get_drvdata(dev);  in spear_rtc_read_alarm()  local
261 	rtc_wait_not_busy(config);  in spear_rtc_read_alarm()
263 	time = readl(config->ioaddr + ALARM_TIME_REG);  in spear_rtc_read_alarm()
264 	date = readl(config->ioaddr + ALARM_DATE_REG);  in spear_rtc_read_alarm()
265 	alm->time.tm_sec = (time >> SECOND_SHIFT) & SECOND_MASK;  in spear_rtc_read_alarm()
266 	alm->time.tm_min = (time >> MINUTE_SHIFT) & MIN_MASK;  in spear_rtc_read_alarm()
267 	alm->time.tm_hour = (time >> HOUR_SHIFT) & HOUR_MASK;  in spear_rtc_read_alarm()
268 	alm->time.tm_mday = (date >> MDAY_SHIFT) & DAY_MASK;  in spear_rtc_read_alarm()
269 	alm->time.tm_mon = (date >> MONTH_SHIFT) & MONTH_MASK;  in spear_rtc_read_alarm()
270 	alm->time.tm_year = (date >> YEAR_SHIFT) & YEAR_MASK;  in spear_rtc_read_alarm()
272 	bcd2tm(&alm->time);  in spear_rtc_read_alarm()
273 	alm->enabled = readl(config->ioaddr + CTRL_REG) & INT_ENABLE;  in spear_rtc_read_alarm()
279  * spear_rtc_set_alarm - set the alarm time
284  * otherwise -ve error is returned.
286 static int spear_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)  in spear_rtc_set_alarm()
288 	struct spear_rtc_config *config = dev_get_drvdata(dev);  in spear_rtc_set_alarm()  local
292 	tm2bcd(&alm->time);  in spear_rtc_set_alarm()
294 	rtc_wait_not_busy(config);  in spear_rtc_set_alarm()
296 	time = (alm->time.tm_sec << SECOND_SHIFT) | (alm->time.tm_min <<  in spear_rtc_set_alarm()
297 			MINUTE_SHIFT) |	(alm->time.tm_hour << HOUR_SHIFT);  in spear_rtc_set_alarm()
298 	date = (alm->time.tm_mday << MDAY_SHIFT) | (alm->time.tm_mon <<  in spear_rtc_set_alarm()
299 			MONTH_SHIFT) | (alm->time.tm_year << YEAR_SHIFT);  in spear_rtc_set_alarm()
301 	writel(time, config->ioaddr + ALARM_TIME_REG);  in spear_rtc_set_alarm()
302 	writel(date, config->ioaddr + ALARM_DATE_REG);  in spear_rtc_set_alarm()
303 	err = is_write_complete(config);  in spear_rtc_set_alarm()
307 	if (alm->enabled)  in spear_rtc_set_alarm()
308 		spear_rtc_enable_interrupt(config);  in spear_rtc_set_alarm()
310 		spear_rtc_disable_interrupt(config);  in spear_rtc_set_alarm()
315 static int spear_alarm_irq_enable(struct device *dev, unsigned int enabled)  in spear_alarm_irq_enable()
317 	struct spear_rtc_config *config = dev_get_drvdata(dev);  in spear_alarm_irq_enable()  local
320 	spear_rtc_clear_interrupt(config);  in spear_alarm_irq_enable()
325 		spear_rtc_disable_interrupt(config);  in spear_alarm_irq_enable()
329 		spear_rtc_enable_interrupt(config);  in spear_alarm_irq_enable()
332 		ret = -EINVAL;  in spear_alarm_irq_enable()
339 static const struct rtc_class_ops spear_rtc_ops = {
347 static int spear_rtc_probe(struct platform_device *pdev)  in spear_rtc_probe()
349 	struct spear_rtc_config *config;  in spear_rtc_probe()  local
353 	config = devm_kzalloc(&pdev->dev, sizeof(*config), GFP_KERNEL);  in spear_rtc_probe()
354 	if (!config)  in spear_rtc_probe()
355 		return -ENOMEM;  in spear_rtc_probe()
357 	config->rtc = devm_rtc_allocate_device(&pdev->dev);  in spear_rtc_probe()
358 	if (IS_ERR(config->rtc))  in spear_rtc_probe()
359 		return PTR_ERR(config->rtc);  in spear_rtc_probe()
366 	status = devm_request_irq(&pdev->dev, irq, spear_rtc_irq, 0, pdev->name,  in spear_rtc_probe()
367 			config);  in spear_rtc_probe()
369 		dev_err(&pdev->dev, "Alarm interrupt IRQ%d already claimed\n",  in spear_rtc_probe()
374 	config->ioaddr = devm_platform_ioremap_resource(pdev, 0);  in spear_rtc_probe()
375 	if (IS_ERR(config->ioaddr))  in spear_rtc_probe()
376 		return PTR_ERR(config->ioaddr);  in spear_rtc_probe()
378 	config->clk = devm_clk_get(&pdev->dev, NULL);  in spear_rtc_probe()
379 	if (IS_ERR(config->clk))  in spear_rtc_probe()
380 		return PTR_ERR(config->clk);  in spear_rtc_probe()
382 	status = clk_prepare_enable(config->clk);  in spear_rtc_probe()
386 	spin_lock_init(&config->lock);  in spear_rtc_probe()
387 	platform_set_drvdata(pdev, config);  in spear_rtc_probe()
389 	config->rtc->ops = &spear_rtc_ops;  in spear_rtc_probe()
390 	config->rtc->range_min = RTC_TIMESTAMP_BEGIN_0000;  in spear_rtc_probe()
391 	config->rtc->range_max = RTC_TIMESTAMP_END_9999;  in spear_rtc_probe()
393 	status = devm_rtc_register_device(config->rtc);  in spear_rtc_probe()
397 	if (!device_can_wakeup(&pdev->dev))  in spear_rtc_probe()
398 		device_init_wakeup(&pdev->dev, true);  in spear_rtc_probe()
403 	clk_disable_unprepare(config->clk);  in spear_rtc_probe()
408 static void spear_rtc_remove(struct platform_device *pdev)  in spear_rtc_remove()
410 	struct spear_rtc_config *config = platform_get_drvdata(pdev);  in spear_rtc_remove()  local
412 	spear_rtc_disable_interrupt(config);  in spear_rtc_remove()
413 	clk_disable_unprepare(config->clk);  in spear_rtc_remove()
414 	device_init_wakeup(&pdev->dev, false);  in spear_rtc_remove()
418 static int spear_rtc_suspend(struct device *dev)  in spear_rtc_suspend()
421 	struct spear_rtc_config *config = platform_get_drvdata(pdev);  in spear_rtc_suspend()  local
425 	if (device_may_wakeup(&pdev->dev)) {  in spear_rtc_suspend()
427 			config->irq_wake = 1;  in spear_rtc_suspend()
429 		spear_rtc_disable_interrupt(config);  in spear_rtc_suspend()
430 		clk_disable(config->clk);  in spear_rtc_suspend()
436 static int spear_rtc_resume(struct device *dev)  in spear_rtc_resume()
439 	struct spear_rtc_config *config = platform_get_drvdata(pdev);  in spear_rtc_resume()  local
444 	if (device_may_wakeup(&pdev->dev)) {  in spear_rtc_resume()
445 		if (config->irq_wake) {  in spear_rtc_resume()
447 			config->irq_wake = 0;  in spear_rtc_resume()
450 		clk_enable(config->clk);  in spear_rtc_resume()
451 		spear_rtc_enable_interrupt(config);  in spear_rtc_resume()
458 static SIMPLE_DEV_PM_OPS(spear_rtc_pm_ops, spear_rtc_suspend, spear_rtc_resume);
460 static void spear_rtc_shutdown(struct platform_device *pdev)  in spear_rtc_shutdown()
462 	struct spear_rtc_config *config = platform_get_drvdata(pdev);  in spear_rtc_shutdown()  local
464 	spear_rtc_disable_interrupt(config);  in spear_rtc_shutdown()
465 	clk_disable(config->clk);  in spear_rtc_shutdown()
469 static const struct of_device_id spear_rtc_id_table[] = {
470 	{ .compatible = "st,spear600-rtc" },
476 static struct platform_driver spear_rtc_driver = {
481 		.name = "rtc-spear",
489 MODULE_ALIAS("platform:rtc-spear");
490 MODULE_AUTHOR("Rajeev Kumar <rajeev-[email protected]>");