rtc: mt6397: Add support for the MediaTek MT6358 RTC

This add support for the MediaTek MT6358 RTC. Driver using
compatible data to store different RTC_WRTGR address offset.
This replace RTC_WRTGR to RTC_WRTGR_MT6323 in mt6323-poweroff
driver which only needed by armv7 CPU without ATF.
Signed-off-by: Ran Bi <ran.bi@mediatek.com>
Signed-off-by: Hsin-Hsiung Wang <hsin-hsiung.wang@mediatek.com>
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Sebastian Reichel <sre@kernel.org>
Reviewed-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/power/reset/mt6323-poweroff.c

@@ -30,7 +30,7 @@ static void mt6323_do_pwroff(void)
 	int ret;
 
 	regmap_write(pwrc->regmap, pwrc->base + RTC_BBPU, RTC_BBPU_KEY);
-	regmap_write(pwrc->regmap, pwrc->base + RTC_WRTGR, 1);
+	regmap_write(pwrc->regmap, pwrc->base + RTC_WRTGR_MT6323, 1);
 
 	ret = regmap_read_poll_timeout(pwrc->regmap,
 					pwrc->base + RTC_BBPU, val,

drivers/rtc/rtc-mt6397.c

@@ -9,6 +9,7 @@
 #include <linux/mfd/mt6397/core.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
 #include <linux/rtc.h>
@@ -20,7 +21,7 @@ static int mtk_rtc_write_trigger(struct mt6397_rtc *rtc)
 	int ret;
 	u32 data;
 
-	ret = regmap_write(rtc->regmap, rtc->addr_base + RTC_WRTGR, 1);
+	ret = regmap_write(rtc->regmap, rtc->addr_base + rtc->data->wrtgr, 1);
 	if (ret < 0)
 		return ret;
 
@@ -269,6 +270,8 @@ static int mtk_rtc_probe(struct platform_device *pdev)
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	rtc->addr_base = res->start;
 
+	rtc->data = of_device_get_match_data(&pdev->dev);
+
 	rtc->irq = platform_get_irq(pdev, 0);
 	if (rtc->irq < 0)
 		return rtc->irq;
@@ -325,9 +328,18 @@ static int mt6397_rtc_resume(struct device *dev)
 static SIMPLE_DEV_PM_OPS(mt6397_pm_ops, mt6397_rtc_suspend,
 			mt6397_rtc_resume);
 
+static const struct mtk_rtc_data mt6358_rtc_data = {
+	.wrtgr = RTC_WRTGR_MT6358,
+};
+
+static const struct mtk_rtc_data mt6397_rtc_data = {
+	.wrtgr = RTC_WRTGR_MT6397,
+};
+
 static const struct of_device_id mt6397_rtc_of_match[] = {
-	{ .compatible = "mediatek,mt6323-rtc", },
-	{ .compatible = "mediatek,mt6397-rtc", },
+	{ .compatible = "mediatek,mt6323-rtc", .data = &mt6397_rtc_data },
+	{ .compatible = "mediatek,mt6358-rtc", .data = &mt6358_rtc_data },
+	{ .compatible = "mediatek,mt6397-rtc", .data = &mt6397_rtc_data },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, mt6397_rtc_of_match);

include/linux/mfd/mt6397/rtc.h

@@ -18,7 +18,9 @@
 #define RTC_BBPU_CBUSY         BIT(6)
 #define RTC_BBPU_KEY            (0x43 << 8)
 
-#define RTC_WRTGR              0x003c
+#define RTC_WRTGR_MT6358       0x003a
+#define RTC_WRTGR_MT6397       0x003c
+#define RTC_WRTGR_MT6323       RTC_WRTGR_MT6397
 
 #define RTC_IRQ_STA            0x0002
 #define RTC_IRQ_STA_AL         BIT(0)
@@ -65,6 +67,10 @@
 #define MTK_RTC_POLL_DELAY_US  10
 #define MTK_RTC_POLL_TIMEOUT   (jiffies_to_usecs(HZ))
 
+struct mtk_rtc_data {
+	u32                     wrtgr;
+};
+
 struct mt6397_rtc {
 	struct device           *dev;
 	struct rtc_device       *rtc_dev;
@@ -74,6 +80,7 @@ struct mt6397_rtc {
 	struct regmap           *regmap;
 	int                     irq;
 	u32                     addr_base;
+	const struct mtk_rtc_data *data;
 };
 
 #endif /* _LINUX_MFD_MT6397_RTC_H_ */