If the platform driver "probe" function fails to register a restart handler, it issues a warning and continues regardless. The corresponding "remove" function unregisters the restart handler regardless.
Use bit 2 of `dw_wdt.state` to indicate whether the restart handler was registered successfully in the "probe" function, and only unregister it in the "remove" function if so. Signed-off-by: Ian Abbott <abbo...@mev.co.uk> --- drivers/watchdog/dw_wdt.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c index cece633..1cd877b 100644 --- a/drivers/watchdog/dw_wdt.c +++ b/drivers/watchdog/dw_wdt.c @@ -62,6 +62,7 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started " /* dw_wdt.state bit numbers */ #define DW_WDT_IN_USE 0 #define DW_WDT_PROBED 1 +#define DW_WDT_RESTART_HANDLER 2 static struct { void __iomem *regs; @@ -366,6 +367,8 @@ static int dw_wdt_drv_probe(struct platform_device *pdev) ret = register_restart_handler(&dw_wdt.restart_handler); if (ret) pr_warn("cannot register restart handler\n"); + else + set_bit(DW_WDT_RESTART_HANDLER, &dw_wdt.state); dw_wdt_set_next_heartbeat(); setup_timer(&dw_wdt.timer, dw_wdt_ping, 0); @@ -384,7 +387,8 @@ out_unmark_probed: static int dw_wdt_drv_remove(struct platform_device *pdev) { - unregister_restart_handler(&dw_wdt.restart_handler); + if (test_and_clear_bit(DW_WDT_RESTART_HANDLER, &dw_wdt.state)) + unregister_restart_handler(&dw_wdt.restart_handler); misc_deregister(&dw_wdt_miscdev); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/