From mboxrd@z Thu Jan 1 00:00:00 1970 From: alexandre.belloni@free-electrons.com (Alexandre Belloni) Date: Fri, 31 Jul 2015 11:39:52 +0200 Subject: [PATCH 16/23] watchdog: at91sam9: get and use slow clock In-Reply-To: <1438335599-3301-1-git-send-email-alexandre.belloni@free-electrons.com> References: <1438335599-3301-1-git-send-email-alexandre.belloni@free-electrons.com> Message-ID: <1438335599-3301-17-git-send-email-alexandre.belloni@free-electrons.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Commit dca1a4b5ff6e ("clk: at91: keep slow clk enabled to prevent system hang") added a workaround for the slow clock as it is not properly handled by its users. Get and use the slow clock as it is necessary for the at91sam9 watchdog. Signed-off-by: Alexandre Belloni Reviewed-by: Guenter Roeck --- Cc: Wim Van Sebroeck Cc: linux-watchdog at vger.kernel.org drivers/watchdog/at91sam9_wdt.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) diff --git a/drivers/watchdog/at91sam9_wdt.c b/drivers/watchdog/at91sam9_wdt.c index e4698f7c5f93..7e6acaf3ece4 100644 --- a/drivers/watchdog/at91sam9_wdt.c +++ b/drivers/watchdog/at91sam9_wdt.c @@ -17,6 +17,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include #include #include #include @@ -90,6 +91,7 @@ struct at91wdt { unsigned long heartbeat; /* WDT heartbeat in jiffies */ bool nowayout; unsigned int irq; + struct clk *sclk; }; /* ......................................................................... */ @@ -352,15 +354,25 @@ static int __init at91wdt_probe(struct platform_device *pdev) if (IS_ERR(wdt->base)) return PTR_ERR(wdt->base); + wdt->sclk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(wdt->sclk)) + return PTR_ERR(wdt->sclk); + + err = clk_prepare_enable(wdt->sclk); + if (err) { + dev_err(&pdev->dev, "Could not enable slow clock\n"); + return err; + } + if (pdev->dev.of_node) { err = of_at91wdt_init(pdev->dev.of_node, wdt); if (err) - return err; + goto err_clk; } err = at91_wdt_init(pdev, wdt); if (err) - return err; + goto err_clk; platform_set_drvdata(pdev, wdt); @@ -368,6 +380,11 @@ static int __init at91wdt_probe(struct platform_device *pdev) wdt->wdd.timeout, wdt->nowayout); return 0; + +err_clk: + clk_disable_unprepare(wdt->sclk); + + return err; } static int __exit at91wdt_remove(struct platform_device *pdev) @@ -377,6 +394,7 @@ static int __exit at91wdt_remove(struct platform_device *pdev) pr_warn("I quit now, hardware will probably reboot!\n"); del_timer(&wdt->timer); + clk_disable_unprepare(wdt->sclk); return 0; } -- 2.1.4