Re: [PATCH v4] phy: samsung: Use readl_poll_timeout function

From: Anand Moon
Date: Thu Jul 16 2020 - 01:56:37 EST


Hi Vinod,

On Thu, 16 Jul 2020 at 11:20, Vinod Koul <vkoul@xxxxxxxxxx> wrote:
>
> On 13-07-20, 07:42, Anand Moon wrote:
> > Instead of a busy waiting while loop using udelay
> > use readl_poll_timeout function to check the condition
> > is met or timeout occurs in crport_handshake function.
> > readl_poll_timeout is called in non atomic context so
> > it safe to sleep until the condition is met.
> >
> > Fixes: d8c80bb3b55b ("phy: exynos5-usbdrd: Calibrate LOS levels for exynos5420/5800")
> > Signed-off-by: Anand Moon <linux.amoon@xxxxxxxxx>
> > ---
> > Changes v4:
> > Rebased on to of patch [0] https://patchwork.kernel.org/patch/11651673/
> > --Fix the commit message.
> > --Fix the error timeout condition for -ETIMEDOUT
> > ---
> > Changes v3:
> > --Fix the commit message.
> > --Drop the variable, used the value directly.
> > Changes v2:
> > --used the default timeout values.
> > --Added missing Fixed tags.
> > ---
> > drivers/phy/samsung/phy-exynos5-usbdrd.c | 39 ++++++++----------------
> > 1 file changed, 12 insertions(+), 27 deletions(-)
> >
> > diff --git a/drivers/phy/samsung/phy-exynos5-usbdrd.c b/drivers/phy/samsung/phy-exynos5-usbdrd.c
> > index 7f6279fb4f8f..ad81aa65cdff 100644
> > --- a/drivers/phy/samsung/phy-exynos5-usbdrd.c
> > +++ b/drivers/phy/samsung/phy-exynos5-usbdrd.c
> > @@ -16,6 +16,7 @@
> > #include <linux/of.h>
> > #include <linux/of_address.h>
> > #include <linux/of_device.h>
> > +#include <linux/iopoll.h>
> > #include <linux/phy/phy.h>
> > #include <linux/platform_device.h>
> > #include <linux/mutex.h>
> > @@ -556,41 +557,25 @@ static int exynos5_usbdrd_phy_power_off(struct phy *phy)
> > static int crport_handshake(struct exynos5_usbdrd_phy *phy_drd,
> > u32 val, u32 cmd)
> > {
> > - u32 usec = 100;
> > unsigned int result;
> > + int err;
> >
> > writel(val | cmd, phy_drd->reg_phy + EXYNOS5_DRD_PHYREG0);
> >
> > - do {
> > - result = readl(phy_drd->reg_phy + EXYNOS5_DRD_PHYREG1);
> > - if (result & PHYREG1_CR_ACK)
> > - break;
> > -
> > - udelay(1);
> > - } while (usec-- > 0);
> > -
> > - if (!usec) {
> > - dev_err(phy_drd->dev,
> > - "CRPORT handshake timeout1 (0x%08x)\n", val);
> > - return -ETIME;
> > + err = readl_poll_timeout(phy_drd->reg_phy + EXYNOS5_DRD_PHYREG1,
> > + result, (result & PHYREG1_CR_ACK), 1, 100);
>
> pls align this line to opening brace of preceding line:
>
> err = readl_poll_timeout(phy_drd->reg_phy + EXYNOS5_DRD_PHYREG1,
> result, (result & PHYREG1_CR_ACK), 1, 100);
>
> This is recommended way of splitting lines, see
> Documentation/process/coding-style.rst and run checkpatch.pl with
> --strict option

Ok, I will do this, just waiting for some more feedback on these changes.
>
> thanks
> --
> ~Vinod

-Anand