1 // SPDX-License-Identifier: GPL-2.0+
3  * APM X-Gene SoC Real Time Clock Driver
17 #include <linux/rtc.h>
20 /* RTC CSR Registers */
36 	struct rtc_device *rtc;  member
47 	rtc_time64_to_tm(readl(pdata->csr_base + RTC_CCVR), tm);  in xgene_rtc_read_time()
59 	writel((u32)rtc_tm_to_time64(tm), pdata->csr_base + RTC_CLR);  in xgene_rtc_set_time()
60 	readl(pdata->csr_base + RTC_CLR); /* Force a barrier */  in xgene_rtc_set_time()
70 	rtc_time64_to_tm(0, &alrm->time);  in xgene_rtc_read_alarm()
71 	alrm->enabled = readl(pdata->csr_base + RTC_CCR) & RTC_CCR_IE;  in xgene_rtc_read_alarm()
81 	ccr = readl(pdata->csr_base + RTC_CCR);  in xgene_rtc_alarm_irq_enable()
89 	writel(ccr, pdata->csr_base + RTC_CCR);  in xgene_rtc_alarm_irq_enable()
98 	return readl(pdata->csr_base + RTC_CCR) & RTC_CCR_IE ? 1 : 0;  in xgene_rtc_alarm_irq_enabled()
105 	writel((u32)rtc_tm_to_time64(&alrm->time), pdata->csr_base + RTC_CMR);  in xgene_rtc_set_alarm()
107 	xgene_rtc_alarm_irq_enable(dev, alrm->enabled);  in xgene_rtc_set_alarm()
125 	if (!(readl(pdata->csr_base + RTC_STAT) & RTC_STAT_BIT))  in xgene_rtc_interrupt()
129 	readl(pdata->csr_base + RTC_EOI);  in xgene_rtc_interrupt()
131 	rtc_update_irq(pdata->rtc, 1, RTC_IRQF | RTC_AF);  in xgene_rtc_interrupt()
142 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);  in xgene_rtc_probe()
144 		return -ENOMEM;  in xgene_rtc_probe()
147 	pdata->csr_base = devm_platform_ioremap_resource(pdev, 0);  in xgene_rtc_probe()
148 	if (IS_ERR(pdata->csr_base))  in xgene_rtc_probe()
149 		return PTR_ERR(pdata->csr_base);  in xgene_rtc_probe()
151 	pdata->rtc = devm_rtc_allocate_device(&pdev->dev);  in xgene_rtc_probe()
152 	if (IS_ERR(pdata->rtc))  in xgene_rtc_probe()
153 		return PTR_ERR(pdata->rtc);  in xgene_rtc_probe()
158 	ret = devm_request_irq(&pdev->dev, irq, xgene_rtc_interrupt, 0,  in xgene_rtc_probe()
159 			       dev_name(&pdev->dev), pdata);  in xgene_rtc_probe()
161 		dev_err(&pdev->dev, "Could not request IRQ\n");  in xgene_rtc_probe()
165 	pdata->clk = devm_clk_get(&pdev->dev, NULL);  in xgene_rtc_probe()
166 	if (IS_ERR(pdata->clk)) {  in xgene_rtc_probe()
167 		dev_err(&pdev->dev, "Couldn't get the clock for RTC\n");  in xgene_rtc_probe()
168 		return -ENODEV;  in xgene_rtc_probe()
170 	ret = clk_prepare_enable(pdata->clk);  in xgene_rtc_probe()
175 	writel(RTC_CCR_EN, pdata->csr_base + RTC_CCR);  in xgene_rtc_probe()
177 	ret = device_init_wakeup(&pdev->dev, true);  in xgene_rtc_probe()
179 		clk_disable_unprepare(pdata->clk);  in xgene_rtc_probe()
183 	pdata->rtc->ops = &xgene_rtc_ops;  in xgene_rtc_probe()
184 	pdata->rtc->range_max = U32_MAX;  in xgene_rtc_probe()
186 	ret = devm_rtc_register_device(pdata->rtc);  in xgene_rtc_probe()
188 		clk_disable_unprepare(pdata->clk);  in xgene_rtc_probe()
199 	xgene_rtc_alarm_irq_enable(&pdev->dev, 0);  in xgene_rtc_remove()
200 	device_init_wakeup(&pdev->dev, false);  in xgene_rtc_remove()
201 	clk_disable_unprepare(pdata->clk);  in xgene_rtc_remove()
213 	 * If this RTC alarm will be used for waking the system up,  in xgene_rtc_suspend()
217 	if (device_may_wakeup(&pdev->dev)) {  in xgene_rtc_suspend()
219 			pdata->irq_wake = 1;  in xgene_rtc_suspend()
221 		pdata->irq_enabled = xgene_rtc_alarm_irq_enabled(dev);  in xgene_rtc_suspend()
223 		clk_disable_unprepare(pdata->clk);  in xgene_rtc_suspend()
237 	if (device_may_wakeup(&pdev->dev)) {  in xgene_rtc_resume()
238 		if (pdata->irq_wake) {  in xgene_rtc_resume()
240 			pdata->irq_wake = 0;  in xgene_rtc_resume()
243 		rc = clk_prepare_enable(pdata->clk);  in xgene_rtc_resume()
248 		xgene_rtc_alarm_irq_enable(dev, pdata->irq_enabled);  in xgene_rtc_resume()
258 	{.compatible = "apm,xgene-rtc" },
268 		.name	= "xgene-rtc",
276 MODULE_DESCRIPTION("APM X-Gene SoC RTC driver");