Instead of using a fixed clock HZ in the driver, obtain it from the "periph" clk that the watchdog timer uses. Signed-off-by: Simon Arlott <simon@xxxxxxxxxxx> --- Changed to check for -EPROBE_DEFER before printing an error. drivers/watchdog/bcm63xx_wdt.c | 38 ++++++++++++++++++++++++++++++++------ 1 file changed, 32 insertions(+), 6 deletions(-) diff --git a/drivers/watchdog/bcm63xx_wdt.c b/drivers/watchdog/bcm63xx_wdt.c index 1d2a501..3c7667a 100644 --- a/drivers/watchdog/bcm63xx_wdt.c +++ b/drivers/watchdog/bcm63xx_wdt.c @@ -13,6 +13,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/clk.h> #include <linux/errno.h> #include <linux/io.h> #include <linux/kernel.h> @@ -32,11 +33,13 @@ #define PFX KBUILD_MODNAME -#define WDT_HZ 50000000 /* Fclk */ +#define WDT_CLK_NAME "periph" struct bcm63xx_wdt_hw { raw_spinlock_t lock; void __iomem *regs; + struct clk *clk; + unsigned long clock_hz; bool running; }; @@ -51,7 +54,7 @@ static int bcm63xx_wdt_start(struct watchdog_device *wdd) unsigned long flags; raw_spin_lock_irqsave(&hw->lock, flags); - bcm_writel(wdd->timeout * WDT_HZ, hw->regs + WDT_DEFVAL_REG); + bcm_writel(wdd->timeout * hw->clock_hz, hw->regs + WDT_DEFVAL_REG); bcm_writel(WDT_START_1, hw->regs + WDT_CTL_REG); bcm_writel(WDT_START_2, hw->regs + WDT_CTL_REG); hw->running = true; @@ -116,7 +119,7 @@ static void bcm63xx_wdt_isr(void *data) die(PFX ": watchdog timer expired\n", get_irq_regs()); } - ms = timeleft / (WDT_HZ / 1000); + ms = timeleft / (hw->clock_hz / 1000); dev_alert(wdd->dev, "warning timer fired, reboot in %ums\n", ms); } @@ -160,14 +163,32 @@ static int bcm63xx_wdt_probe(struct platform_device *pdev) return -ENXIO; } + hw->clk = devm_clk_get(&pdev->dev, WDT_CLK_NAME); + if (IS_ERR(hw->clk)) { + if (PTR_ERR(hw->clk) != -EPROBE_DEFER) + dev_err(&pdev->dev, "unable to request clock\n"); + return PTR_ERR(hw->clk); + } + + hw->clock_hz = clk_get_rate(hw->clk); + if (!hw->clock_hz) { + dev_err(&pdev->dev, "unable to fetch clock rate\n"); + return -EINVAL; + } + + ret = clk_prepare_enable(hw->clk); + if (ret) { + dev_err(&pdev->dev, "unable to enable clock\n"); + return ret; + } + raw_spin_lock_init(&hw->lock); - hw->running = false; wdd->parent = &pdev->dev; wdd->ops = &bcm63xx_wdt_ops; wdd->info = &bcm63xx_wdt_info; wdd->min_timeout = 1; - wdd->max_timeout = 0xffffffff / WDT_HZ; + wdd->max_timeout = 0xffffffff / hw->clock_hz; wdd->timeout = min(30U, wdd->max_timeout); watchdog_set_drvdata(wdd, hw); @@ -179,7 +200,7 @@ static int bcm63xx_wdt_probe(struct platform_device *pdev) ret = bcm63xx_timer_register(TIMER_WDT_ID, bcm63xx_wdt_isr, wdd); if (ret < 0) { dev_err(&pdev->dev, "failed to register wdt timer isr\n"); - return ret; + goto disable_clk; } ret = watchdog_register_device(wdd); @@ -197,15 +218,20 @@ static int bcm63xx_wdt_probe(struct platform_device *pdev) unregister_timer: bcm63xx_timer_unregister(TIMER_WDT_ID); + +disable_clk: + clk_disable_unprepare(hw->clk); return ret; } static int bcm63xx_wdt_remove(struct platform_device *pdev) { struct watchdog_device *wdd = platform_get_drvdata(pdev); + struct bcm63xx_wdt_hw *hw = watchdog_get_drvdata(wdd); bcm63xx_timer_unregister(TIMER_WDT_ID); watchdog_unregister_device(wdd); + clk_disable_unprepare(hw->clk); return 0; } -- 2.1.4 -- Simon Arlott -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html