diff options
Diffstat (limited to 'drivers/watchdog')
| -rw-r--r-- | drivers/watchdog/dw_wdt.c | 48 |
1 files changed, 43 insertions, 5 deletions
diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c index 693c0d1fd796..efbc36872670 100644 --- a/drivers/watchdog/dw_wdt.c +++ b/drivers/watchdog/dw_wdt.c @@ -68,6 +68,7 @@ struct dw_wdt_timeout { struct dw_wdt { void __iomem *regs; struct clk *clk; + struct clk *pclk; unsigned long rate; struct dw_wdt_timeout timeouts[DW_WDT_NUM_TOPS]; struct watchdog_device wdd; @@ -274,6 +275,7 @@ static int dw_wdt_suspend(struct device *dev) dw_wdt->control = readl(dw_wdt->regs + WDOG_CONTROL_REG_OFFSET); dw_wdt->timeout = readl(dw_wdt->regs + WDOG_TIMEOUT_RANGE_REG_OFFSET); + clk_disable_unprepare(dw_wdt->pclk); clk_disable_unprepare(dw_wdt->clk); return 0; @@ -287,6 +289,12 @@ static int dw_wdt_resume(struct device *dev) if (err) return err; + err = clk_prepare_enable(dw_wdt->pclk); + if (err) { + clk_disable_unprepare(dw_wdt->clk); + return err; + } + writel(dw_wdt->timeout, dw_wdt->regs + WDOG_TIMEOUT_RANGE_REG_OFFSET); writel(dw_wdt->control, dw_wdt->regs + WDOG_CONTROL_REG_OFFSET); @@ -393,9 +401,18 @@ static int dw_wdt_drv_probe(struct platform_device *pdev) if (IS_ERR(dw_wdt->regs)) return PTR_ERR(dw_wdt->regs); - dw_wdt->clk = devm_clk_get(dev, NULL); - if (IS_ERR(dw_wdt->clk)) - return PTR_ERR(dw_wdt->clk); + /* + * Try to request the watchdog dedicated timer clock source. It must + * be supplied if asynchronous mode is enabled. Otherwise fallback + * to the common timer/bus clocks configuration, in which the very + * first found clock supply both timer and APB signals. + */ + dw_wdt->clk = devm_clk_get(dev, "tclk"); + if (IS_ERR(dw_wdt->clk)) { + dw_wdt->clk = devm_clk_get(dev, NULL); + if (IS_ERR(dw_wdt->clk)) + return PTR_ERR(dw_wdt->clk); + } ret = clk_prepare_enable(dw_wdt->clk); if (ret) @@ -407,10 +424,27 @@ static int dw_wdt_drv_probe(struct platform_device *pdev) goto out_disable_clk; } + /* + * Request APB clock if device is configured with async clocks mode. + * In this case both tclk and pclk clocks are supposed to be specified. + * Alas we can't know for sure whether async mode was really activated, + * so the pclk phandle reference is left optional. If it couldn't be + * found we consider the device configured in synchronous clocks mode. + */ + dw_wdt->pclk = devm_clk_get_optional(dev, "pclk"); + if (IS_ERR(dw_wdt->pclk)) { + ret = PTR_ERR(dw_wdt->pclk); + goto out_disable_clk; + } + + ret = clk_prepare_enable(dw_wdt->pclk); + if (ret) + goto out_disable_clk; + dw_wdt->rst = devm_reset_control_get_optional_shared(&pdev->dev, NULL); if (IS_ERR(dw_wdt->rst)) { ret = PTR_ERR(dw_wdt->rst); - goto out_disable_clk; + goto out_disable_pclk; } reset_control_deassert(dw_wdt->rst); @@ -449,10 +483,13 @@ static int dw_wdt_drv_probe(struct platform_device *pdev) ret = watchdog_register_device(wdd); if (ret) - goto out_disable_clk; + goto out_disable_pclk; return 0; +out_disable_pclk: + clk_disable_unprepare(dw_wdt->pclk); + out_disable_clk: clk_disable_unprepare(dw_wdt->clk); return ret; @@ -464,6 +501,7 @@ static int dw_wdt_drv_remove(struct platform_device *pdev) watchdog_unregister_device(&dw_wdt->wdd); reset_control_assert(dw_wdt->rst); + clk_disable_unprepare(dw_wdt->pclk); clk_disable_unprepare(dw_wdt->clk); return 0; |