diff options
Diffstat (limited to 'drivers/watchdog/sprd_wdt.c')
-rw-r--r-- | drivers/watchdog/sprd_wdt.c | 43 |
1 files changed, 21 insertions, 22 deletions
diff --git a/drivers/watchdog/sprd_wdt.c b/drivers/watchdog/sprd_wdt.c index 65cb55f3916f..4e689b6ff141 100644 --- a/drivers/watchdog/sprd_wdt.c +++ b/drivers/watchdog/sprd_wdt.c @@ -6,6 +6,7 @@ #include <linux/bitops.h> #include <linux/clk.h> +#include <linux/delay.h> #include <linux/device.h> #include <linux/err.h> #include <linux/interrupt.h> @@ -53,7 +54,7 @@ #define SPRD_WDT_CNT_HIGH_SHIFT 16 #define SPRD_WDT_LOW_VALUE_MASK GENMASK(15, 0) -#define SPRD_WDT_LOAD_TIMEOUT 1000 +#define SPRD_WDT_LOAD_TIMEOUT 11 struct sprd_wdt { void __iomem *base; @@ -108,6 +109,23 @@ static int sprd_wdt_load_value(struct sprd_wdt *wdt, u32 timeout, u32 tmr_step = timeout * SPRD_WDT_CNT_STEP; u32 prtmr_step = pretimeout * SPRD_WDT_CNT_STEP; + /* + * Checking busy bit to make sure the previous loading operation is + * done. According to the specification, the busy bit would be set + * after a new loading operation and last 2 or 3 RTC clock + * cycles (about 60us~92us). + */ + do { + val = readl_relaxed(wdt->base + SPRD_WDT_INT_RAW); + if (!(val & SPRD_WDT_LD_BUSY_BIT)) + break; + + usleep_range(10, 100); + } while (delay_cnt++ < SPRD_WDT_LOAD_TIMEOUT); + + if (delay_cnt >= SPRD_WDT_LOAD_TIMEOUT) + return -EBUSY; + sprd_wdt_unlock(wdt->base); writel_relaxed((tmr_step >> SPRD_WDT_CNT_HIGH_SHIFT) & SPRD_WDT_LOW_VALUE_MASK, wdt->base + SPRD_WDT_LOAD_HIGH); @@ -120,20 +138,6 @@ static int sprd_wdt_load_value(struct sprd_wdt *wdt, u32 timeout, wdt->base + SPRD_WDT_IRQ_LOAD_LOW); sprd_wdt_lock(wdt->base); - /* - * Waiting the load value operation done, - * it needs two or three RTC clock cycles. - */ - do { - val = readl_relaxed(wdt->base + SPRD_WDT_INT_RAW); - if (!(val & SPRD_WDT_LD_BUSY_BIT)) - break; - - cpu_relax(); - } while (delay_cnt++ < SPRD_WDT_LOAD_TIMEOUT); - - if (delay_cnt >= SPRD_WDT_LOAD_TIMEOUT) - return -EBUSY; return 0; } @@ -345,15 +349,10 @@ static int __maybe_unused sprd_wdt_pm_resume(struct device *dev) if (ret) return ret; - if (watchdog_active(&wdt->wdd)) { + if (watchdog_active(&wdt->wdd)) ret = sprd_wdt_start(&wdt->wdd); - if (ret) { - sprd_wdt_disable(wdt); - return ret; - } - } - return 0; + return ret; } static const struct dev_pm_ops sprd_wdt_pm_ops = { |