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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>
This commit is contained in:
Jia-Ju Bai 2018-04-11 09:43:26 +08:00 committed by Marc Kleine-Budde
parent 276b7361bb
commit c8d4dea2a8
1 changed files with 1 additions and 1 deletions
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2
drivers/net/can/sja1000/peak_pcmcia.c
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@ -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);