Re: [PATCH] watchdog: imx2_wdt: Drop .remove callback

From: Guenter Roeck
Date: Sun Feb 23 2020 - 23:04:39 EST


On 2/23/20 6:51 PM, Anson Huang wrote:
.remove callback implementation doesn' call clk_disable_unprepare() which
is buggy, actually, we can just use devm_watchdog_register_device() and
devm_add_action_or_reset() to handle all necessary operations for remove
action, then .remove callback can be dropped.

Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>

---
drivers/watchdog/imx2_wdt.c | 37 ++++++++++---------------------------
1 file changed, 10 insertions(+), 27 deletions(-)

diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c
index f8d58bf..1fe472f 100644
--- a/drivers/watchdog/imx2_wdt.c
+++ b/drivers/watchdog/imx2_wdt.c
@@ -244,6 +244,11 @@ static const struct regmap_config imx2_wdt_regmap_config = {
.max_register = 0x8,
};
+static void imx2_wdt_action(void *data)
+{
+ clk_disable_unprepare(data);
+}
+
static int __init imx2_wdt_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -292,6 +297,10 @@ static int __init imx2_wdt_probe(struct platform_device *pdev)
if (ret)
return ret;
+ ret = devm_add_action_or_reset(dev, imx2_wdt_action, wdev->clk);
+ if (ret)
+ return ret;
+
regmap_read(wdev->regmap, IMX2_WDT_WRSR, &val);
wdog->bootstatus = val & IMX2_WDT_WRSR_TOUT ? WDIOF_CARDRESET : 0;
@@ -315,32 +324,7 @@ static int __init imx2_wdt_probe(struct platform_device *pdev)
*/
regmap_write(wdev->regmap, IMX2_WDT_WMCR, 0);
- ret = watchdog_register_device(wdog);
- if (ret)
- goto disable_clk;
-
- dev_info(dev, "timeout %d sec (nowayout=%d)\n",
- wdog->timeout, nowayout);
-
- return 0;
-
-disable_clk:
- clk_disable_unprepare(wdev->clk);
- return ret;
-}
-
-static int __exit imx2_wdt_remove(struct platform_device *pdev)
-{
- struct watchdog_device *wdog = platform_get_drvdata(pdev);
- struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
-
- watchdog_unregister_device(wdog);
-
- if (imx2_wdt_is_running(wdev)) {
- imx2_wdt_ping(wdog);
- dev_crit(&pdev->dev, "Device removed: Expect reboot!\n");
- }
- return 0;
+ return devm_watchdog_register_device(dev, wdog);
}
static void imx2_wdt_shutdown(struct platform_device *pdev)
@@ -417,7 +401,6 @@ static const struct of_device_id imx2_wdt_dt_ids[] = {
MODULE_DEVICE_TABLE(of, imx2_wdt_dt_ids);
static struct platform_driver imx2_wdt_driver = {
- .remove = __exit_p(imx2_wdt_remove),
.shutdown = imx2_wdt_shutdown,
.driver = {
.name = DRIVER_NAME,