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Subject[PATCH 1/3] mmc: wbsd: Replace mdelay with usleep_range in wbsd_init
Date
wbsd_init() is never called in atomic context.

The call chains ending up at wbsd_init() are:
[1] wbsd_init() <- wbsd_probe()
[2] wbsd_init() <- wbsd_pnp_probe()

wbsd_probe() is set as ".probe" in struct platform_driver.
wbsd_pnp_probe() is set as ".probe" in struct pnp_driver.
These functions are not called in atomic context.

Despite never getting called from atomic context, wbsd_init()
calls mdelay() to busily wait.
This is not necessary and can be replaced with usleep_range() to
avoid busy waiting.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
---
drivers/mmc/host/wbsd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mmc/host/wbsd.c b/drivers/mmc/host/wbsd.c
index 546aaf8..6224d12 100644
--- a/drivers/mmc/host/wbsd.c
+++ b/drivers/mmc/host/wbsd.c
@@ -1709,7 +1709,7 @@ static int wbsd_init(struct device *dev, int base, int irq, int dma,
/*
* Allow device to initialise itself properly.
*/
- mdelay(5);
+ usleep_range(5000, 6000);

/*
* Reset the chip into a known state.
--
1.9.1
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