Merge tag 'iio-fixes-for-4.17a' of git://git.kernel.org/pub/scm/linux/kernel/git...

[linux.git] / drivers / watchdog / renesas_wdt.c

diff --git a/drivers/watchdog/renesas_wdt.c b/drivers/watchdog/renesas_wdt.c
index 831ef83f6de15bce49cbb0839124f0c6cd1a7b60..514db5cc159511254f62c2eb86714a2ecddb978f 100644 (file)
--- a/drivers/watchdog/renesas_wdt.c
+++ b/drivers/watchdog/renesas_wdt.c
@@ -16,6 +16,8 @@
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
+#include <linux/smp.h>
+#include <linux/sys_soc.h>
 #include <linux/watchdog.h>
 
 #define RWTCNT         0
@@ -49,6 +51,7 @@ struct rwdt_priv {
        void __iomem *base;
        struct watchdog_device wdev;
        unsigned long clk_rate;
+       u16 time_left;
        u8 cks;
 };
 
@@ -107,8 +110,19 @@ static unsigned int rwdt_get_timeleft(struct watchdog_device *wdev)
        return DIV_BY_CLKS_PER_SEC(priv, 65536 - val);
 }
 
+static int rwdt_restart(struct watchdog_device *wdev, unsigned long action,
+                       void *data)
+{
+       struct rwdt_priv *priv = watchdog_get_drvdata(wdev);
+
+       rwdt_start(wdev);
+       rwdt_write(priv, 0xffff, RWTCNT);
+       return 0;
+}
+
 static const struct watchdog_info rwdt_ident = {
-       .options = WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT,
+       .options = WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT |
+               WDIOF_CARDRESET,
        .identity = "Renesas WDT Watchdog",
 };
 
@@ -118,8 +132,47 @@ static const struct watchdog_ops rwdt_ops = {
        .stop = rwdt_stop,
        .ping = rwdt_init_timeout,
        .get_timeleft = rwdt_get_timeleft,
+       .restart = rwdt_restart,
+};
+
+#if defined(CONFIG_ARCH_RCAR_GEN2) && defined(CONFIG_SMP)
+/*
+ * Watchdog-reset integration is broken on early revisions of R-Car Gen2 SoCs
+ */
+static const struct soc_device_attribute rwdt_quirks_match[] = {
+       {
+               .soc_id = "r8a7790",
+               .revision = "ES1.*",
+               .data = (void *)1,      /* needs single CPU */
+       }, {
+               .soc_id = "r8a7791",
+               .revision = "ES[12].*",
+               .data = (void *)1,      /* needs single CPU */
+       }, {
+               .soc_id = "r8a7792",
+               .revision = "*",
+               .data = (void *)0,      /* needs SMP disabled */
+       },
+       { /* sentinel */ }
 };
 
+static bool rwdt_blacklisted(struct device *dev)
+{
+       const struct soc_device_attribute *attr;
+
+       attr = soc_device_match(rwdt_quirks_match);
+       if (attr && setup_max_cpus > (uintptr_t)attr->data) {
+               dev_info(dev, "Watchdog blacklisted on %s %s\n", attr->soc_id,
+                        attr->revision);
+               return true;
+       }
+
+       return false;
+}
+#else /* !CONFIG_ARCH_RCAR_GEN2 || !CONFIG_SMP */
+static inline bool rwdt_blacklisted(struct device *dev) { return false; }
+#endif /* !CONFIG_ARCH_RCAR_GEN2 || !CONFIG_SMP */
+
 static int rwdt_probe(struct platform_device *pdev)
 {
        struct rwdt_priv *priv;
@@ -128,6 +181,9 @@ static int rwdt_probe(struct platform_device *pdev)
        unsigned long clks_per_sec;
        int ret, i;
 
+       if (rwdt_blacklisted(&pdev->dev))
+               return -ENODEV;
+
        priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
        if (!priv)
                return -ENOMEM;
@@ -142,9 +198,10 @@ static int rwdt_probe(struct platform_device *pdev)
                return PTR_ERR(clk);
 
        pm_runtime_enable(&pdev->dev);
-
        pm_runtime_get_sync(&pdev->dev);
        priv->clk_rate = clk_get_rate(clk);
+       priv->wdev.bootstatus = (readb_relaxed(priv->base + RWTCSRA) &
+                               RWTCSRA_WOVF) ? WDIOF_CARDRESET : 0;
        pm_runtime_put(&pdev->dev);
 
        if (!priv->clk_rate) {
@@ -176,6 +233,7 @@ static int rwdt_probe(struct platform_device *pdev)
        platform_set_drvdata(pdev, priv);
        watchdog_set_drvdata(&priv->wdev, priv);
        watchdog_set_nowayout(&priv->wdev, nowayout);
+       watchdog_set_restart_priority(&priv->wdev, 0);
 
        /* This overrides the default timeout only if DT configuration was found */
        ret = watchdog_init_timeout(&priv->wdev, 0, &pdev->dev);
@@ -203,12 +261,32 @@ static int rwdt_remove(struct platform_device *pdev)
        return 0;
 }
 
-/*
- * This driver does also fit for R-Car Gen2 (r8a779[0-4]) WDT. However, for SMP
- * to work there, one also needs a RESET (RST) driver which does not exist yet
- * due to HW issues. This needs to be solved before adding compatibles here.
- */
+static int __maybe_unused rwdt_suspend(struct device *dev)
+{
+       struct rwdt_priv *priv = dev_get_drvdata(dev);
+
+       if (watchdog_active(&priv->wdev)) {
+               priv->time_left = readw(priv->base + RWTCNT);
+               rwdt_stop(&priv->wdev);
+       }
+       return 0;
+}
+
+static int __maybe_unused rwdt_resume(struct device *dev)
+{
+       struct rwdt_priv *priv = dev_get_drvdata(dev);
+
+       if (watchdog_active(&priv->wdev)) {
+               rwdt_start(&priv->wdev);
+               rwdt_write(priv, priv->time_left, RWTCNT);
+       }
+       return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(rwdt_pm_ops, rwdt_suspend, rwdt_resume);
+
 static const struct of_device_id rwdt_ids[] = {
+       { .compatible = "renesas,rcar-gen2-wdt", },
        { .compatible = "renesas,rcar-gen3-wdt", },
        { /* sentinel */ }
 };
@@ -218,6 +296,7 @@ static struct platform_driver rwdt_driver = {
        .driver = {
                .name = "renesas_wdt",
                .of_match_table = rwdt_ids,
+               .pm = &rwdt_pm_ops,
        },
        .probe = rwdt_probe,
        .remove = rwdt_remove,