watchdog: orion: Introduce an orion_watchdog device structure

In order to prepare to support multiple compatible-strings, this
commit adds a device structure to hold the driver's state.

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Tested-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Acked-by: Wim Van Sebroeck <wim@iguana.be>
Tested-By: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

1 files changed, 69 insertions, 45 deletions

diff --git a/drivers/watchdog/orion_wdt.c b/drivers/watchdog/orion_wdt.c
index 65aa65560730..9d3a5b97845b 100644
--- a/drivers/watchdog/orion_wdt.c
+++ b/drivers/watchdog/orion_wdt.c
@@ -44,55 +44,66 @@
 
 static bool nowayout = WATCHDOG_NOWAYOUT;
 static int heartbeat = -1;              /* module parameter (seconds) */
-static unsigned int wdt_max_duration;   /* (seconds) */
-static struct clk *clk;
-static unsigned int wdt_tclk;
-static void __iomem *wdt_reg;
-static void __iomem *wdt_rstout;
+
+struct orion_watchdog {
+        struct watchdog_device wdt;
+        void __iomem *reg;
+        void __iomem *rstout;
+        unsigned long clk_rate;
+        struct clk *clk;
+};
 
 static int orion_wdt_ping(struct watchdog_device *wdt_dev)
 {
+        struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
         /* Reload watchdog duration */
-        writel(wdt_tclk * wdt_dev->timeout, wdt_reg + WDT_VAL);
+        writel(dev->clk_rate * wdt_dev->timeout, dev->reg + WDT_VAL);
         return 0;
 }
 
 static int orion_wdt_start(struct watchdog_device *wdt_dev)
 {
+        struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
+
         /* Set watchdog duration */
-        writel(wdt_tclk * wdt_dev->timeout, wdt_reg + WDT_VAL);
+        writel(dev->clk_rate * wdt_dev->timeout, dev->reg + WDT_VAL);
 
         /* Enable watchdog timer */
-        atomic_io_modify(wdt_reg + TIMER_CTRL, WDT_EN, WDT_EN);
+        atomic_io_modify(dev->reg + TIMER_CTRL, WDT_EN, WDT_EN);
 
         /* Enable reset on watchdog */
-        atomic_io_modify(wdt_rstout, WDT_RESET_OUT_EN, WDT_RESET_OUT_EN);
+        atomic_io_modify(dev->rstout, WDT_RESET_OUT_EN, WDT_RESET_OUT_EN);
+
         return 0;
 }
 
 static int orion_wdt_stop(struct watchdog_device *wdt_dev)
 {
+        struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
+
         /* Disable reset on watchdog */
-        atomic_io_modify(wdt_rstout, WDT_RESET_OUT_EN, 0);
+        atomic_io_modify(dev->rstout, WDT_RESET_OUT_EN, 0);
 
         /* Disable watchdog timer */
-        atomic_io_modify(wdt_reg + TIMER_CTRL, WDT_EN, 0);
+        atomic_io_modify(dev->reg + TIMER_CTRL, WDT_EN, 0);
+
         return 0;
 }
 
-static int orion_wdt_enabled(void)
+static int orion_wdt_enabled(struct orion_watchdog *dev)
 {
         bool enabled, running;
 
-        enabled = readl(wdt_rstout) & WDT_RESET_OUT_EN;
-        running = readl(wdt_reg + TIMER_CTRL) & WDT_EN;
+        enabled = readl(dev->rstout) & WDT_RESET_OUT_EN;
+        running = readl(dev->reg + TIMER_CTRL) & WDT_EN;
 
         return enabled && running;
 }
 
 static unsigned int orion_wdt_get_timeleft(struct watchdog_device *wdt_dev)
 {
-        return readl(wdt_reg + WDT_VAL) / wdt_tclk;
+        struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
+        return readl(dev->reg + WDT_VAL) / dev->clk_rate;
 }
 
 static int orion_wdt_set_timeout(struct watchdog_device *wdt_dev,
@@ -116,12 +127,6 @@ static const struct watchdog_ops orion_wdt_ops = {
         .get_timeleft = orion_wdt_get_timeleft,
 };
 
-static struct watchdog_device orion_wdt = {
-        .info = &orion_wdt_info,
-        .ops = &orion_wdt_ops,
-        .min_timeout = 1,
-};
-
 static irqreturn_t orion_wdt_irq(int irq, void *devid)
 {
         panic("Watchdog Timeout");
@@ -157,18 +162,29 @@ static void __iomem *orion_wdt_ioremap_rstout(struct platform_device *pdev,
 
 static int orion_wdt_probe(struct platform_device *pdev)
 {
+        struct orion_watchdog *dev;
+        unsigned int wdt_max_duration;  /* (seconds) */
         struct resource *res;
         int ret, irq;
 
-        clk = devm_clk_get(&pdev->dev, NULL);
-        if (IS_ERR(clk)) {
+        dev = devm_kzalloc(&pdev->dev, sizeof(struct orion_watchdog),
+                           GFP_KERNEL);
+        if (!dev)
+                return -ENOMEM;
+
+        dev->wdt.info = &orion_wdt_info;
+        dev->wdt.ops = &orion_wdt_ops;
+        dev->wdt.min_timeout = 1;
+
+        dev->clk = devm_clk_get(&pdev->dev, NULL);
+        if (IS_ERR(dev->clk)) {
                 dev_err(&pdev->dev, "Orion Watchdog missing clock\n");
-                return PTR_ERR(clk);
+                return PTR_ERR(dev->clk);
         }
-        ret = clk_prepare_enable(clk);
+        ret = clk_prepare_enable(dev->clk);
         if (ret)
                 return ret;
-        wdt_tclk = clk_get_rate(clk);
+        dev->clk_rate = clk_get_rate(dev->clk);
 
         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
         if (!res) {
@@ -176,24 +192,28 @@ static int orion_wdt_probe(struct platform_device *pdev)
                 goto disable_clk;
         }
 
-        wdt_reg = devm_ioremap(&pdev->dev, res->start, resource_size(res));
-        if (!wdt_reg) {
+        dev->reg = devm_ioremap(&pdev->dev, res->start,
+                               resource_size(res));
+        if (!dev->reg) {
                 ret = -ENOMEM;
                 goto disable_clk;
         }
 
-        wdt_rstout = orion_wdt_ioremap_rstout(pdev, res->start &
-                                                    INTERNAL_REGS_MASK);
-        if (!wdt_rstout) {
+        dev->rstout = orion_wdt_ioremap_rstout(pdev, res->start &
+                                                     INTERNAL_REGS_MASK);
+        if (!dev->rstout) {
                 ret = -ENODEV;
                 goto disable_clk;
         }
 
-        wdt_max_duration = WDT_MAX_CYCLE_COUNT / wdt_tclk;
+        wdt_max_duration = WDT_MAX_CYCLE_COUNT / dev->clk_rate;
+
+        dev->wdt.timeout = wdt_max_duration;
+        dev->wdt.max_timeout = wdt_max_duration;
+        watchdog_init_timeout(&dev->wdt, heartbeat, &pdev->dev);
 
-        orion_wdt.timeout = wdt_max_duration;
-        orion_wdt.max_timeout = wdt_max_duration;
-        watchdog_init_timeout(&orion_wdt, heartbeat, &pdev->dev);
+        platform_set_drvdata(pdev, &dev->wdt);
+        watchdog_set_drvdata(&dev->wdt, dev);
 
         /*
          * Let's make sure the watchdog is fully stopped, unless it's
@@ -201,8 +221,8 @@ static int orion_wdt_probe(struct platform_device *pdev)
          * removed and re-insterted, or if the bootloader explicitly
          * set a running watchdog before booting the kernel.
          */
-        if (!orion_wdt_enabled())
-                orion_wdt_stop(&orion_wdt);
+        if (!orion_wdt_enabled(dev))
+                orion_wdt_stop(&dev->wdt);
 
         /* Request the IRQ only after the watchdog is disabled */
         irq = platform_get_irq(pdev, 0);
@@ -212,37 +232,41 @@ static int orion_wdt_probe(struct platform_device *pdev)
                  * watchdog, so let's make it optional.
                  */
                 ret = devm_request_irq(&pdev->dev, irq, orion_wdt_irq, 0,
-                                       pdev->name, &orion_wdt);
+                                       pdev->name, dev);
                 if (ret < 0) {
                         dev_err(&pdev->dev, "failed to request IRQ\n");
                         goto disable_clk;
                 }
         }
 
-        watchdog_set_nowayout(&orion_wdt, nowayout);
-        ret = watchdog_register_device(&orion_wdt);
+        watchdog_set_nowayout(&dev->wdt, nowayout);
+        ret = watchdog_register_device(&dev->wdt);
         if (ret)
                 goto disable_clk;
 
         pr_info("Initial timeout %d sec%s\n",
-                orion_wdt.timeout, nowayout ? ", nowayout" : "");
+                dev->wdt.timeout, nowayout ? ", nowayout" : "");
         return 0;
 
 disable_clk:
-        clk_disable_unprepare(clk);
+        clk_disable_unprepare(dev->clk);
         return ret;
 }
 
 static int orion_wdt_remove(struct platform_device *pdev)
 {
-        watchdog_unregister_device(&orion_wdt);
-        clk_disable_unprepare(clk);
+        struct watchdog_device *wdt_dev = platform_get_drvdata(pdev);
+        struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
+
+        watchdog_unregister_device(wdt_dev);
+        clk_disable_unprepare(dev->clk);
         return 0;
 }
 
 static void orion_wdt_shutdown(struct platform_device *pdev)
 {
-        orion_wdt_stop(&orion_wdt);
+        struct watchdog_device *wdt_dev = platform_get_drvdata(pdev);
+        orion_wdt_stop(wdt_dev);
 }
 
 static const struct of_device_id orion_wdt_of_match_table[] = {