[PATCH v2] i2c: avoid sleep in IRQ context

Fuqian Huang
2019-08-07T07:18:20Z

i2c_pxa_handler -> i2c_pxa_irq_txempty ->
i2c_pxa_reset -> i2c_pxa_set_slave -> i2c_pxa_wait_slave

As i2c_pxa_handler is an interrupt handler, it will finally
calls i2c_pxa_wait_slave which calls msleep.

Add in_interrupt check before msleep to avoid sleep
in IRQ context.
When in interrupt context, use mdelay instead of msleep.

Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com>
---
drivers/i2c/busses/i2c-pxa.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 2c3c3d6935c0..876e693bafd9 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -456,7 +456,10 @@ static int i2c_pxa_wait_slave(struct pxa_i2c *i2c)
return 1;
}

- msleep(1);
+ if (in_interrupt())
+ mdelay(1);
+ else
+ msleep(1);
}

if (i2c_debug > 0)
--
2.11.0