watchdog: jz4740: Use regmap provided by TCU driver

Since we broke the ABI by changing the clock, the driver was also
updated to use the regmap provided by the TCU driver.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Tested-by: Mathieu Malaterre <malat@debian.org>
Tested-by: Artur Rojek <contact@artur-rojek.eu>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20191023174714.14362-2-paul@crapouillou.net
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

drivers/watchdog/Kconfig

@@ -1645,6 +1645,7 @@ config JZ4740_WDT
 	depends on MACH_JZ4740 || MACH_JZ4780
 	depends on COMMON_CLK
 	select WATCHDOG_CORE
+	select MFD_SYSCON
 	help
 	  Hardware driver for the built-in watchdog timer on Ingenic jz4740 SoCs.
 

drivers/watchdog/jz4740_wdt.c

@@ -5,6 +5,7 @@
  */
 
 #include <linux/mfd/ingenic-tcu.h>
+#include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/types.h>
@@ -17,6 +18,7 @@
 #include <linux/slab.h>
 #include <linux/err.h>
 #include <linux/of.h>
+#include <linux/regmap.h>
 
 #define DEFAULT_HEARTBEAT 5
 #define MAX_HEARTBEAT     2048
@@ -36,7 +38,7 @@ MODULE_PARM_DESC(heartbeat,
 
 struct jz4740_wdt_drvdata {
 	struct watchdog_device wdt;
-	void __iomem *base;
+	struct regmap *map;
 	struct clk *clk;
 	unsigned long clk_rate;
 };
@@ -45,7 +47,8 @@ static int jz4740_wdt_ping(struct watchdog_device *wdt_dev)
 {
 	struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
 
-	writew(0x0, drvdata->base + TCU_REG_WDT_TCNT);
+	regmap_write(drvdata->map, TCU_REG_WDT_TCNT, 0);
+
 	return 0;
 }
 
@@ -54,16 +57,16 @@ static int jz4740_wdt_set_timeout(struct watchdog_device *wdt_dev,
 {
 	struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
 	u16 timeout_value = (u16)(drvdata->clk_rate * new_timeout);
-	u8 tcer;
+	unsigned int tcer;
 
-	tcer = readb(drvdata->base + TCU_REG_WDT_TCER);
-	writeb(0x0, drvdata->base + TCU_REG_WDT_TCER);
+	regmap_read(drvdata->map, TCU_REG_WDT_TCER, &tcer);
+	regmap_write(drvdata->map, TCU_REG_WDT_TCER, 0);
 
-	writew((u16)timeout_value, drvdata->base + TCU_REG_WDT_TDR);
-	writew(0x0, drvdata->base + TCU_REG_WDT_TCNT);
+	regmap_write(drvdata->map, TCU_REG_WDT_TDR, timeout_value);
+	regmap_write(drvdata->map, TCU_REG_WDT_TCNT, 0);
 
 	if (tcer & TCU_WDT_TCER_TCEN)
-		writeb(TCU_WDT_TCER_TCEN, drvdata->base + TCU_REG_WDT_TCER);
+		regmap_write(drvdata->map, TCU_REG_WDT_TCER, TCU_WDT_TCER_TCEN);
 
 	wdt_dev->timeout = new_timeout;
 	return 0;
@@ -72,20 +75,20 @@ static int jz4740_wdt_set_timeout(struct watchdog_device *wdt_dev,
 static int jz4740_wdt_start(struct watchdog_device *wdt_dev)
 {
 	struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
+	unsigned int tcer;
 	int ret;
-	u8 tcer;
 
 	ret = clk_prepare_enable(drvdata->clk);
 	if (ret)
 		return ret;
 
-	tcer = readb(drvdata->base + TCU_REG_WDT_TCER);
+	regmap_read(drvdata->map, TCU_REG_WDT_TCER, &tcer);
 
 	jz4740_wdt_set_timeout(wdt_dev, wdt_dev->timeout);
 
 	/* Start watchdog if it wasn't started already */
 	if (!(tcer & TCU_WDT_TCER_TCEN))
-		writeb(TCU_WDT_TCER_TCEN, drvdata->base + TCU_REG_WDT_TCER);
+		regmap_write(drvdata->map, TCU_REG_WDT_TCER, TCU_WDT_TCER_TCEN);
 
 	return 0;
 }
@@ -94,7 +97,7 @@ static int jz4740_wdt_stop(struct watchdog_device *wdt_dev)
 {
 	struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
 
-	writeb(0x0, drvdata->base + TCU_REG_WDT_TCER);
+	regmap_write(drvdata->map, TCU_REG_WDT_TCER, 0);
 	clk_disable_unprepare(drvdata->clk);
 
 	return 0;
@@ -172,9 +175,11 @@ static int jz4740_wdt_probe(struct platform_device *pdev)
 	watchdog_set_nowayout(jz4740_wdt, nowayout);
 	watchdog_set_drvdata(jz4740_wdt, drvdata);
 
-	drvdata->base = devm_platform_ioremap_resource(pdev, 0);
-	if (IS_ERR(drvdata->base))
-		return PTR_ERR(drvdata->base);
+	drvdata->map = device_node_to_regmap(dev->parent->of_node);
+	if (!drvdata->map) {
+		dev_err(dev, "regmap not found\n");
+		return -EINVAL;
+	}
 
 	return devm_watchdog_register_device(dev, &drvdata->wdt);
 }