watchdog: msc313e: Enable clock before accessing hardware registers

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msc313e_wdt_probe() reads from hardware registers without ensuring the
required clock is enabled.  Furthermore, if the bootloader leaves the
watchdog running, msc313e_wdt_probe() sets WDOG_HW_RUNNING without
increasing the clock's reference count.

While the clock is currently supplied as a fixed clock by the device
tree (`xtal_div2` in arch/arm/boot/dts/sigmastar/mstar-v7.dtsi) which
masks the physical issue, this still violates the API usage.

Call clk_prepare_enable() before reading WDT registers.  If the WDT is
running, leave the clock enabled so the CCF reference counter is
balanced.

Fixes: ffd264bd15 ("watchdog: msc313e: Check if the WDT was running at boot")
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://patch.msgid.link/20260828161348.13212-5-tzungbi@kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

...

This commit is contained in:

Tzung-Bi Shih 2026-08-29 00:13:43 +08:00 • committed by Guenter Roeck

parent 3db30f3159

commit 3db2df24e7

1 changed files with 21 additions and 2 deletions

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drivers/watchdog/msc313e_wdt.c

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