pinctrl: mediatek: use spin lock in mtk_rmw
Commit 42a46434e9b1 ("pinctrl: add lock in mtk_rmw function.") uses
mutex lock in mtk_rmw. However the function is possible called from
atomic context.
For example call trace:
mutex_lock+0x28/0x64
mtk_rmw+0x38/0x80
[snip]
max98357a_daiops_trigger+0x8c/0x9c
soc_pcm_trigger+0x5c/0x10c
The max98357a_daiops_trigger() could run in either atomic or non-atomic
context. As a result, dmesg shows some similar messages: "BUG: sleeping
function called from invalid context at kernel/locking/mutex.c:254".
Uses spin lock in mtk_rmw instead.
Fixes: 42a46434e9b1 ("pinctrl: add lock in mtk_rmw function.")
Signed-off-by: Tzung-Bi Shih <tzungbi@google.com>
Link: https://lore.kernel.org/r/20210419093449.3125704-1-tzungbi@google.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.h b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.h
index be35443..a6f1bdb 100644
--- a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.h
+++ b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.h
@@ -253,7 +253,7 @@ struct mtk_pinctrl {
struct mtk_pinctrl_group *groups;
const char **grp_names;
/* lock pin's register resource to avoid multiple threads issue*/
- struct mutex lock;
+ spinlock_t lock;
};
void mtk_rmw(struct mtk_pinctrl *pctl, u8 i, u32 reg, u32 mask, u32 set);