[PATCH 11/14] drm/bridge: analogix_dp: don't wait for PLL lock too early

[Robert Foss]

On Fri, May 3, 2024 at 5:12 PM Lucas Stach <l.stach at pengutronix.de> wrote:
>
> The PLL will be reconfigured later, which may cause it to go out of lock
> anyways, so there is no point in waiting for the PLL to lock here. Instead
> we can continue execution of the link setup, which will properly set the
> PLL parameters and will wait for the PLL to lock at the appropriate times.
>
> Signed-off-by: Lucas Stach <l.stach at pengutronix.de>
> ---
>  drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c | 14 +-------------
>  1 file changed, 1 insertion(+), 13 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
> index d267cf05cbca..e9c643a8b6fc 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
> @@ -356,7 +356,6 @@ void analogix_dp_set_analog_power_down(struct analogix_dp_device *dp,
>  int analogix_dp_init_analog_func(struct analogix_dp_device *dp)
>  {
>         u32 reg;
> -       int timeout_loop = 0;
>
>         analogix_dp_set_analog_power_down(dp, POWER_ALL, 0);
>
> @@ -368,18 +367,7 @@ int analogix_dp_init_analog_func(struct analogix_dp_device *dp)
>         writel(reg, dp->reg_base + ANALOGIX_DP_DEBUG_CTL);
>
>         /* Power up PLL */
> -       if (analogix_dp_get_pll_lock_status(dp) == PLL_UNLOCKED) {
> -               analogix_dp_set_pll_power_down(dp, 0);
> -
> -               while (analogix_dp_get_pll_lock_status(dp) == PLL_UNLOCKED) {
> -                       timeout_loop++;
> -                       if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
> -                               dev_err(dp->dev, "failed to get pll lock status\n");
> -                               return -ETIMEDOUT;
> -                       }
> -                       usleep_range(10, 20);
> -               }
> -       }
> +       analogix_dp_set_pll_power_down(dp, 0);
>
>         /* Enable Serdes FIFO function and Link symbol clock domain module */
>         reg = readl(dp->reg_base + ANALOGIX_DP_FUNC_EN_2);
> --
> 2.39.2
>


Reviewed-by: Robert Foss <rfoss at kernel.org>