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authorPaul Cercueil <paul@crapouillou.net>2019-06-07 18:24:27 +0200
committerWim Van Sebroeck <wim@linux-watchdog.org>2019-07-08 16:10:11 +0200
commit9b3461188e86f19113f57a71c8873fab6ca95f36 (patch)
treeeb2f091e8972b123ccd343958c59b577a1fcd0d0 /drivers/watchdog
parentdf04cce3b8f9124fbb201edde84b591fd38d2169 (diff)
watchdog: jz4740: Avoid starting watchdog in set_timeout
Previously the jz4740_wdt_set_timeout() function was starting the timer unconditionally, even if it was stopped when that function was entered. Now, the timer will be restarted only if it was already running before this function is called. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Diffstat (limited to 'drivers/watchdog')
-rw-r--r--drivers/watchdog/jz4740_wdt.c14
1 files changed, 13 insertions, 1 deletions
diff --git a/drivers/watchdog/jz4740_wdt.c b/drivers/watchdog/jz4740_wdt.c
index f1199db7bffa..d4a90916dd38 100644
--- a/drivers/watchdog/jz4740_wdt.c
+++ b/drivers/watchdog/jz4740_wdt.c
@@ -68,6 +68,7 @@ static int jz4740_wdt_set_timeout(struct watchdog_device *wdt_dev,
unsigned int rtc_clk_rate;
unsigned int timeout_value;
unsigned short clock_div = JZ_WDT_CLOCK_DIV_1;
+ u8 tcer;
rtc_clk_rate = clk_get_rate(drvdata->rtc_clk);
@@ -83,6 +84,7 @@ static int jz4740_wdt_set_timeout(struct watchdog_device *wdt_dev,
clock_div += (1 << TCU_TCSR_PRESCALE_LSB);
}
+ tcer = readb(drvdata->base + TCU_REG_WDT_TCER);
writeb(0x0, drvdata->base + TCU_REG_WDT_TCER);
writew(clock_div, drvdata->base + TCU_REG_WDT_TCSR);
@@ -90,7 +92,8 @@ static int jz4740_wdt_set_timeout(struct watchdog_device *wdt_dev,
writew(0x0, drvdata->base + TCU_REG_WDT_TCNT);
writew(clock_div | JZ_WDT_CLOCK_RTC, drvdata->base + TCU_REG_WDT_TCSR);
- writeb(0x1, drvdata->base + TCU_REG_WDT_TCER);
+ if (tcer & TCU_WDT_TCER_TCEN)
+ writeb(TCU_WDT_TCER_TCEN, drvdata->base + TCU_REG_WDT_TCER);
wdt_dev->timeout = new_timeout;
return 0;
@@ -98,9 +101,18 @@ static int jz4740_wdt_set_timeout(struct watchdog_device *wdt_dev,
static int jz4740_wdt_start(struct watchdog_device *wdt_dev)
{
+ struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
+ u8 tcer;
+
+ tcer = readb(drvdata->base + TCU_REG_WDT_TCER);
+
jz4740_timer_enable_watchdog();
jz4740_wdt_set_timeout(wdt_dev, wdt_dev->timeout);
+ /* Start watchdog if it wasn't started already */
+ if (!(tcer & TCU_WDT_TCER_TCEN))
+ writeb(TCU_WDT_TCER_TCEN, drvdata->base + TCU_REG_WDT_TCER);
+
return 0;
}