From a66633052cb56e3ccd2bcf065ef3b199c24a4b0d Mon Sep 17 00:00:00 2001 From: Jia-Ju Bai <baijiaju1990@gmail.com> Date: Wed, 11 Apr 2018 09:43:26 +0800 Subject: [PATCH] can: sja1000: Replace mdelay with usleep_range in pcan_add_channels pcan_add_channels() is never called in atomic context. pcan_add_channels() is only called by pcan_probe(), which is only set as ".probe" in struct pcmcia_driver. Despite never getting called from atomic context, pcan_add_channels() 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> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> --- drivers/net/can/sja1000/peak_pcmcia.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/can/sja1000/peak_pcmcia.c b/drivers/net/can/sja1000/peak_pcmcia.c index 485b19c9ae47e..b8c39ede7cd51 100644 --- a/drivers/net/can/sja1000/peak_pcmcia.c +++ b/drivers/net/can/sja1000/peak_pcmcia.c @@ -530,7 +530,7 @@ static int pcan_add_channels(struct pcan_pccard *card) pcan_write_reg(card, PCC_CCR, ccr); /* wait 2ms before unresetting channels */ - mdelay(2); + usleep_range(2000, 3000); ccr &= ~PCC_CCR_RST_ALL; pcan_write_reg(card, PCC_CCR, ccr); -- 2.39.5