diff options
Diffstat (limited to 'drivers/watchdog/rzg2l_wdt.c')
| -rw-r--r-- | drivers/watchdog/rzg2l_wdt.c | 112 |
1 files changed, 86 insertions, 26 deletions
diff --git a/drivers/watchdog/rzg2l_wdt.c b/drivers/watchdog/rzg2l_wdt.c index 974a4194a8fd..1c9aa366d0a0 100644 --- a/drivers/watchdog/rzg2l_wdt.c +++ b/drivers/watchdog/rzg2l_wdt.c @@ -10,8 +10,9 @@ #include <linux/io.h> #include <linux/kernel.h> #include <linux/module.h> -#include <linux/of_device.h> +#include <linux/of.h> #include <linux/platform_device.h> +#include <linux/pm_domain.h> #include <linux/pm_runtime.h> #include <linux/reset.h> #include <linux/units.h> @@ -35,6 +36,8 @@ #define F2CYCLE_NSEC(f) (1000000000 / (f)) +#define RZV2M_A_NSEC 730 + static bool nowayout = WATCHDOG_NOWAYOUT; module_param(nowayout, bool, 0); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" @@ -96,8 +99,17 @@ static void rzg2l_wdt_init_timeout(struct watchdog_device *wdev) static int rzg2l_wdt_start(struct watchdog_device *wdev) { struct rzg2l_wdt_priv *priv = watchdog_get_drvdata(wdev); + int ret; - pm_runtime_get_sync(wdev->parent); + ret = pm_runtime_resume_and_get(wdev->parent); + if (ret) + return ret; + + ret = reset_control_deassert(priv->rstc); + if (ret) { + pm_runtime_put(wdev->parent); + return ret; + } /* Initialize time out */ rzg2l_wdt_init_timeout(wdev); @@ -114,41 +126,69 @@ static int rzg2l_wdt_start(struct watchdog_device *wdev) static int rzg2l_wdt_stop(struct watchdog_device *wdev) { struct rzg2l_wdt_priv *priv = watchdog_get_drvdata(wdev); + int ret; + + ret = reset_control_assert(priv->rstc); + if (ret) + return ret; - pm_runtime_put(wdev->parent); - reset_control_reset(priv->rstc); + ret = pm_runtime_put(wdev->parent); + if (ret < 0) + return ret; return 0; } static int rzg2l_wdt_set_timeout(struct watchdog_device *wdev, unsigned int timeout) { - struct rzg2l_wdt_priv *priv = watchdog_get_drvdata(wdev); + int ret = 0; wdev->timeout = timeout; /* * If the watchdog is active, reset the module for updating the WDTSET - * register so that it is updated with new timeout values. + * register by calling rzg2l_wdt_stop() (which internally calls reset_control_reset() + * to reset the module) so that it is updated with new timeout values. */ if (watchdog_active(wdev)) { - pm_runtime_put(wdev->parent); - reset_control_reset(priv->rstc); - rzg2l_wdt_start(wdev); + ret = rzg2l_wdt_stop(wdev); + if (ret) + return ret; + + ret = rzg2l_wdt_start(wdev); } - return 0; + return ret; } static int rzg2l_wdt_restart(struct watchdog_device *wdev, unsigned long action, void *data) { struct rzg2l_wdt_priv *priv = watchdog_get_drvdata(wdev); + int ret; - clk_prepare_enable(priv->pclk); - clk_prepare_enable(priv->osc_clk); + /* + * In case of RZ/G3S the watchdog device may be part of an IRQ safe power + * domain that is currently powered off. In this case we need to power + * it on before accessing registers. Along with this the clocks will be + * enabled. We don't undo the pm_runtime_resume_and_get() as the device + * need to be on for the reboot to happen. + * + * For the rest of SoCs not registering a watchdog IRQ safe power + * domain it is safe to call pm_runtime_resume_and_get() as the + * irq_safe_dev_in_sleep_domain() call in genpd_runtime_resume() + * returns non zero value and the genpd_lock() is avoided, thus, there + * will be no invalid wait context reported by lockdep. + */ + ret = pm_runtime_resume_and_get(wdev->parent); + if (ret) + return ret; if (priv->devtype == WDT_RZG2L) { + ret = reset_control_deassert(priv->rstc); + if (ret) + return ret; + /* Generate Reset (WDTRSTB) Signal on parity error */ rzg2l_wdt_write(priv, 0, PECR); @@ -156,6 +196,9 @@ static int rzg2l_wdt_restart(struct watchdog_device *wdev, rzg2l_wdt_write(priv, PEEN_FORCE, PEEN); } else { /* RZ/V2M doesn't have parity error registers */ + ret = reset_control_reset(priv->rstc); + if (ret) + return ret; wdev->timeout = 0; @@ -198,13 +241,11 @@ static const struct watchdog_ops rzg2l_wdt_ops = { .restart = rzg2l_wdt_restart, }; -static void rzg2l_wdt_reset_assert_pm_disable(void *data) +static void rzg2l_wdt_pm_disable(void *data) { struct watchdog_device *wdev = data; - struct rzg2l_wdt_priv *priv = watchdog_get_drvdata(wdev); pm_runtime_disable(wdev->parent); - reset_control_assert(priv->rstc); } static int rzg2l_wdt_probe(struct platform_device *pdev) @@ -247,12 +288,9 @@ static int rzg2l_wdt_probe(struct platform_device *pdev) return dev_err_probe(&pdev->dev, PTR_ERR(priv->rstc), "failed to get cpg reset"); - ret = reset_control_deassert(priv->rstc); - if (ret) - return dev_err_probe(dev, ret, "failed to deassert"); - priv->devtype = (uintptr_t)of_device_get_match_data(dev); + pm_runtime_irq_safe(&pdev->dev); pm_runtime_enable(&pdev->dev); priv->wdev.info = &rzg2l_wdt_ident; @@ -264,18 +302,15 @@ static int rzg2l_wdt_probe(struct platform_device *pdev) priv->wdev.timeout = WDT_DEFAULT_TIMEOUT; watchdog_set_drvdata(&priv->wdev, priv); - ret = devm_add_action_or_reset(&pdev->dev, - rzg2l_wdt_reset_assert_pm_disable, - &priv->wdev); - if (ret < 0) + dev_set_drvdata(dev, priv); + ret = devm_add_action_or_reset(&pdev->dev, rzg2l_wdt_pm_disable, &priv->wdev); + if (ret) return ret; watchdog_set_nowayout(&priv->wdev, nowayout); watchdog_stop_on_unregister(&priv->wdev); - ret = watchdog_init_timeout(&priv->wdev, 0, dev); - if (ret) - dev_warn(dev, "Specified timeout invalid, using default"); + watchdog_init_timeout(&priv->wdev, 0, dev); return devm_watchdog_register_device(&pdev->dev, &priv->wdev); } @@ -287,10 +322,35 @@ static const struct of_device_id rzg2l_wdt_ids[] = { }; MODULE_DEVICE_TABLE(of, rzg2l_wdt_ids); +static int rzg2l_wdt_suspend_late(struct device *dev) +{ + struct rzg2l_wdt_priv *priv = dev_get_drvdata(dev); + + if (!watchdog_active(&priv->wdev)) + return 0; + + return rzg2l_wdt_stop(&priv->wdev); +} + +static int rzg2l_wdt_resume_early(struct device *dev) +{ + struct rzg2l_wdt_priv *priv = dev_get_drvdata(dev); + + if (!watchdog_active(&priv->wdev)) + return 0; + + return rzg2l_wdt_start(&priv->wdev); +} + +static const struct dev_pm_ops rzg2l_wdt_pm_ops = { + LATE_SYSTEM_SLEEP_PM_OPS(rzg2l_wdt_suspend_late, rzg2l_wdt_resume_early) +}; + static struct platform_driver rzg2l_wdt_driver = { .driver = { .name = "rzg2l_wdt", .of_match_table = rzg2l_wdt_ids, + .pm = &rzg2l_wdt_pm_ops, }, .probe = rzg2l_wdt_probe, }; |