Fwd: [PATCH 2/8] watchdog: davinci: use davinci_wdt_device structure to hold device data

[ivan.khoronzhuk]

Some SoCs, like Keystone 2, can support more than one WDT and each
watchdog device has to use it's own base address, clock source,
wdd device, so add new davinci_wdt_device structure to hold device
data.

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk at ti.com>
---
 drivers/watchdog/davinci_wdt.c |   74 ++++++++++++++++++++++++++--------------
 1 file changed, 48 insertions(+), 26 deletions(-)

diff --git a/drivers/watchdog/davinci_wdt.c b/drivers/watchdog/davinci_wdt.c
index a6eef71..1fc2093 100644
--- a/drivers/watchdog/davinci_wdt.c
+++ b/drivers/watchdog/davinci_wdt.c
@@ -56,9 +56,18 @@
 #define WDKEY_SEQ1		(0xda7e << 16)
 
 static int heartbeat = MAX_HEARTBEAT + 1;
-static void __iomem	*wdt_base;
-struct clk		*wdt_clk;
-static struct watchdog_device	wdt_wdd;
+
+/*
+ * struct to hold data for each WDT device
+ * @base - base io address of WD device
+ * @clk - source clock of WDT
+ * @wdd - hold watchdog device as is in WDT core
+ */
+struct davinci_wdt_device {
+	void __iomem		*base;
+	struct clk		*clk;
+	struct watchdog_device	wdd;
+};
 
 /* davinci_wdt_start - enable watchdog */
 static int davinci_wdt_start(struct watchdog_device *wdd)
@@ -66,42 +75,45 @@ static int davinci_wdt_start(struct watchdog_device *wdd)
 	u32 tgcr;
 	u32 timer_margin;
 	unsigned long wdt_freq;
+	struct davinci_wdt_device *davinci_wdt = watchdog_get_drvdata(wdd);
 
-	wdt_freq = clk_get_rate(wdt_clk);
+	wdt_freq = clk_get_rate(davinci_wdt->clk);
 
 	/* disable, internal clock source */
-	iowrite32(0, wdt_base + TCR);
+	iowrite32(0, davinci_wdt->base + TCR);
 	/* reset timer, set mode to 64-bit watchdog, and unreset */
-	iowrite32(0, wdt_base + TGCR);
+	iowrite32(0, davinci_wdt->base + TGCR);
 	tgcr = TIMMODE_64BIT_WDOG | TIM12RS_UNRESET | TIM34RS_UNRESET;
-	iowrite32(tgcr, wdt_base + TGCR);
+	iowrite32(tgcr, davinci_wdt->base + TGCR);
 	/* clear counter regs */
-	iowrite32(0, wdt_base + TIM12);
-	iowrite32(0, wdt_base + TIM34);
+	iowrite32(0, davinci_wdt->base + TIM12);
+	iowrite32(0, davinci_wdt->base + TIM34);
 	/* set timeout period */
 	timer_margin = (((u64)wdd->timeout * wdt_freq) & 0xffffffff);
-	iowrite32(timer_margin, wdt_base + PRD12);
+	iowrite32(timer_margin, davinci_wdt->base + PRD12);
 	timer_margin = (((u64)wdd->timeout * wdt_freq) >> 32);
-	iowrite32(timer_margin, wdt_base + PRD34);
+	iowrite32(timer_margin, davinci_wdt->base + PRD34);
 	/* enable run continuously */
-	iowrite32(ENAMODE12_PERIODIC, wdt_base + TCR);
+	iowrite32(ENAMODE12_PERIODIC, davinci_wdt->base + TCR);
 	/* Once the WDT is in pre-active state write to
 	 * TIM12, TIM34, PRD12, PRD34, TCR, TGCR, WDTCR are
 	 * write protected (except for the WDKEY field)
 	 */
 	/* put watchdog in pre-active state */
-	iowrite32(WDKEY_SEQ0 | WDEN, wdt_base + WDTCR);
+	iowrite32(WDKEY_SEQ0 | WDEN, davinci_wdt->base + WDTCR);
 	/* put watchdog in active state */
-	iowrite32(WDKEY_SEQ1 | WDEN, wdt_base + WDTCR);
+	iowrite32(WDKEY_SEQ1 | WDEN, davinci_wdt->base + WDTCR);
 	return 0;
 }
 
 static int davinci_wdt_ping(struct watchdog_device *wdd)
 {
+	struct davinci_wdt_device *davinci_wdt = watchdog_get_drvdata(wdd);
+
 	/* put watchdog in service state */
-	iowrite32(WDKEY_SEQ0, wdt_base + WDTCR);
+	iowrite32(WDKEY_SEQ0, davinci_wdt->base + WDTCR);
 	/* put watchdog in active state */
-	iowrite32(WDKEY_SEQ1, wdt_base + WDTCR);
+	iowrite32(WDKEY_SEQ1, davinci_wdt->base + WDTCR);
 	return 0;
 }
 
@@ -123,14 +135,21 @@ static int davinci_wdt_probe(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	struct resource  *wdt_mem;
 	struct watchdog_device *wdd;
+	struct davinci_wdt_device *davinci_wdt;
+
+	davinci_wdt = devm_kzalloc(dev, sizeof(*davinci_wdt), GFP_KERNEL);
+	if (!davinci_wdt)
+		return -ENOMEM;
 
-	wdt_clk = devm_clk_get(dev, NULL);
-	if (WARN_ON(IS_ERR(wdt_clk)))
-		return PTR_ERR(wdt_clk);
+	davinci_wdt->clk = devm_clk_get(dev, NULL);
+	if (WARN_ON(IS_ERR(davinci_wdt->clk)))
+		return PTR_ERR(davinci_wdt->clk);
 
-	clk_prepare_enable(wdt_clk);
+	clk_prepare_enable(davinci_wdt->clk);
 
-	wdd			= &wdt_wdd;
+	platform_set_drvdata(pdev, davinci_wdt);
+
+	wdd			= &davinci_wdt->wdd;
 	wdd->info		= &davinci_wdt_info;
 	wdd->ops		= &davinci_wdt_ops;
 	wdd->min_timeout 	= 1;
@@ -142,12 +161,13 @@ static int davinci_wdt_probe(struct platform_device *pdev)
 
 	dev_info(dev, "heartbeat %d sec\n", wdd->timeout);
 
+	watchdog_set_drvdata(wdd, davinci_wdt);
 	watchdog_set_nowayout(wdd, WATCHDOG_NOWAYOUT);
 
 	wdt_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	wdt_base = devm_ioremap_resource(dev, wdt_mem);
-	if (IS_ERR(wdt_base))
-		return PTR_ERR(wdt_base);
+	davinci_wdt->base = devm_ioremap_resource(dev, wdt_mem);
+	if (IS_ERR(davinci_wdt->base))
+		return PTR_ERR(davinci_wdt->base);
 
 	ret = watchdog_register_device(wdd);
 	if (ret < 0)
@@ -158,8 +178,10 @@ static int davinci_wdt_probe(struct platform_device *pdev)
 
 static int davinci_wdt_remove(struct platform_device *pdev)
 {
-	watchdog_unregister_device(&wdt_wdd);
-	clk_disable_unprepare(wdt_clk);
+	struct davinci_wdt_device *davinci_wdt = platform_get_drvdata(pdev);
+
+	watchdog_unregister_device(&davinci_wdt->wdd);
+	clk_disable_unprepare(davinci_wdt->clk);
 
 	return 0;
 }
-- 
1.7.9.5