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author | Jia-Ju Bai <baijiaju1990@gmail.com> | 2018-01-25 18:32:59 +0800 |
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committer | Tejun Heo <tj@kernel.org> | 2018-01-25 07:28:23 -0800 |
commit | eada8598e69f9ff767c387951f40bab5aafe6a88 (patch) | |
tree | 8646a9f0e57abd09f8287337ff9359209f86284b /drivers/ata/pata_it821x.c | |
parent | e72685dbd2e7782ce99ccd198e52dc0d9cf1d16f (diff) | |
download | talos-op-linux-eada8598e69f9ff767c387951f40bab5aafe6a88.tar.gz talos-op-linux-eada8598e69f9ff767c387951f40bab5aafe6a88.zip |
ata: pata_it821x: Replace mdelay with usleep_range in it821x_firmware_command
After checking all possible call chains to it821x_firmware_command here,
my tool finds that it821x_firmware_command
is never called in atomic context,
namely never in an interrupt handler or holding a spinlock.
And it821x_firmware_command calls kmalloc(GFP_KERNEL),
so it proves again that it821x_firmware_command
can call functions which can sleep.
Thus mdelay can be replaced with usleep_range to avoid busy wait.
This is found by a static analysis tool named DCNS written by myself.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'drivers/ata/pata_it821x.c')
-rw-r--r-- | drivers/ata/pata_it821x.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/ata/pata_it821x.c b/drivers/ata/pata_it821x.c index 7a21edf89e72..8468b300193b 100644 --- a/drivers/ata/pata_it821x.c +++ b/drivers/ata/pata_it821x.c @@ -683,7 +683,7 @@ static u8 *it821x_firmware_command(struct ata_port *ap, u8 cmd, int len) ioread16_rep(ap->ioaddr.data_addr, buf, len/2); return (u8 *)buf; } - mdelay(1); + usleep_range(500, 1000); } kfree(buf); printk(KERN_ERR "it821x_firmware_command: timeout\n"); |