2018-07-27 09:03:30

by Jia-Ju Bai

Subject: [PATCH] sound: pci: cthw20k2: Replace mdelay() with msleep() and usleep_range()

hw_pll_init(), hw_dac_stop(), hw_dac_start() and hw_adc_init()
are never called in atomic context.
They call mdelay() to busily wait, which is not necessary.
mdelay() can be replaced with msleep().

This is found by a static analysis tool named DCNS written by myself.

Signed-off-by: Jia-Ju Bai <[email protected]>
---
sound/pci/ctxfi/cthw20k2.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/sound/pci/ctxfi/cthw20k2.c b/sound/pci/ctxfi/cthw20k2.c
index b866d6b2c923..3c966fafc754 100644
--- a/sound/pci/ctxfi/cthw20k2.c
+++ b/sound/pci/ctxfi/cthw20k2.c
@@ -1316,12 +1316,12 @@ static int hw_pll_init(struct hw *hw, unsigned int rsr)
set_field(&pllctl, PLLCTL_FD, 48000 == rsr ? 16 - 4 : 147 - 4);
set_field(&pllctl, PLLCTL_RD, 48000 == rsr ? 1 - 1 : 10 - 1);
hw_write_20kx(hw, PLL_CTL, pllctl);
- mdelay(40);
+ msleep(40);

pllctl = hw_read_20kx(hw, PLL_CTL);
set_field(&pllctl, PLLCTL_FD, 48000 == rsr ? 16 - 2 : 147 - 2);
hw_write_20kx(hw, PLL_CTL, pllctl);
- mdelay(40);
+ msleep(40);

for (i = 0; i < 1000; i++) {
pllstat = hw_read_20kx(hw, PLL_STAT);
@@ -1584,7 +1584,7 @@ static void hw_dac_stop(struct hw *hw)
data = hw_read_20kx(hw, GPIO_DATA);
data &= 0xFFFFFFFD;
hw_write_20kx(hw, GPIO_DATA, data);
- mdelay(10);
+ usleep_range(10000, 11000);
}

static void hw_dac_start(struct hw *hw)
@@ -1593,7 +1593,7 @@ static void hw_dac_start(struct hw *hw)
data = hw_read_20kx(hw, GPIO_DATA);
data |= 0x2;
hw_write_20kx(hw, GPIO_DATA, data);
- mdelay(50);
+ msleep(50);
}

static void hw_dac_reset(struct hw *hw)
@@ -1864,11 +1864,11 @@ static int hw_adc_init(struct hw *hw, const struct adc_conf *info)
hw_write_20kx(hw, GPIO_DATA, data);
}

- mdelay(10);
+ usleep_range(10000, 11000);
/* Return the ADC to normal operation. */
data |= (0x1 << 15);
hw_write_20kx(hw, GPIO_DATA, data);
- mdelay(50);
+ msleep(50);

/* I2C write to register offset 0x0B to set ADC LRCLK polarity */
/* invert bit, interface format to I2S, word length to 24-bit, */
--
2.17.0

2018-07-27 09:53:09

by Takashi Iwai

Subject: Re: [PATCH] sound: pci: cthw20k2: Replace mdelay() with msleep() and usleep_range()

On Fri, 27 Jul 2018 11:01:43 +0200,
Jia-Ju Bai wrote:
>
> hw_pll_init(), hw_dac_stop(), hw_dac_start() and hw_adc_init()
> are never called in atomic context.
> They call mdelay() to busily wait, which is not necessary.
> mdelay() can be replaced with msleep().
>
> This is found by a static analysis tool named DCNS written by myself.
>
> Signed-off-by: Jia-Ju Bai <[email protected]>

Applied, thanks.


Takashi