After checking all possible call chains to pdc_adjust_pll and
pdc_detect_pll_input_clock,
my tool finds that these functions are never called in atomic context,
namely never in an interrupt handler or holding a spinlock.
And their caller functions pdc2027x_init_one and pdc2027x_reinit_one
calls pci_enable_device which can sleep, and no spinlock is held when
calling pdc_adjust_pll and pdc_detect_pll_input_clock,
so it proves that pdc_adjust_pll and pdc_detect_pll_input_clock
can call functions which can sleep.
Thus mdelay can be replaced with msleep to avoid busy wait.
Signed-off-by: Jia-Ju Bai <[email protected]>
---
drivers/ata/pata_pdc2027x.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/ata/pata_pdc2027x.c b/drivers/ata/pata_pdc2027x.c
index ffd8d33..4e8584d 100644
--- a/drivers/ata/pata_pdc2027x.c
+++ b/drivers/ata/pata_pdc2027x.c
@@ -580,7 +580,7 @@ static void pdc_adjust_pll(struct ata_host *host, long pll_clock, unsigned int b
ioread16(mmio_base + PDC_PLL_CTL); /* flush */
/* Wait the PLL circuit to be stable */
- mdelay(30);
+ msleep(30);
#ifdef PDC_DEBUG
/*
@@ -620,7 +620,7 @@ static long pdc_detect_pll_input_clock(struct ata_host *host)
start_time = ktime_get();
/* Let the counter run for 100 ms. */
- mdelay(100);
+ msleep(100);
/* Read the counter values again */
end_count = pdc_read_counter(host);
--
1.7.9.5
On Thu, Jan 25, 2018 at 06:45:05PM +0800, Jia-Ju Bai wrote:
> After checking all possible call chains to pdc_adjust_pll and
> pdc_detect_pll_input_clock,
> my tool finds that these functions are never called in atomic context,
> namely never in an interrupt handler or holding a spinlock.
> And their caller functions pdc2027x_init_one and pdc2027x_reinit_one
> calls pci_enable_device which can sleep, and no spinlock is held when
> calling pdc_adjust_pll and pdc_detect_pll_input_clock,
> so it proves that pdc_adjust_pll and pdc_detect_pll_input_clock
> can call functions which can sleep.
> Thus mdelay can be replaced with msleep to avoid busy wait.
>
> Signed-off-by: Jia-Ju Bai <[email protected]>
Applied to libata/for-4.16.
Thanks.
--
tejun