Re: [PATCH RSEND] drm/bridge: analogix_dp: use devm_phy_optional_get() for the DP PHY

[Damon Ding <damon.ding@rock-chips.com>]

On 9/24/2026 11:24 AM, Damon Ding wrote:
> Hi Jun,
> 
> On 9/24/2026 10:04 AM, Jun Yan wrote:
>> The DP PHY is optional: the Rockchip RK3399 eDP controller (used as the
>> internal eDP port) has no separate PHY device and relies on its built-in
>> PHY, which is programmed directly through the GRF registers, so its DT
>> node carries no "phys"/"phy-names" property.
>>
>> Requesting the PHY with devm_phy_get() therefore returns -ENODEV (or
>> -ENOSYS when CONFIG_GENERIC_PHY is disabled) and the driver logs a
>> misleading "no DP phy configured" error at probe time before falling back
>> to a NULL phy.
>>
>> Use devm_phy_optional_get() instead, which returns NULL when the PHY is
>> absent and otherwise behaves identically, and drop the manual -ENODEV/
>> -ENOSYS handling. This also removes the spurious error message.
>>
>> Assisted-by: Claude:deepseek-v4-flash
>> Signed-off-by: Jun Yan <jerrysteve1101@gmail.com>
>> ---
>>   .../gpu/drm/bridge/analogix/analogix_dp_core.c | 18 +++---------------
>>   1 file changed, 3 insertions(+), 15 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/ 
>> drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
>> index 18e76d1e78e1..28eb668d3e3f 100644
>> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
>> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
>> @@ -1427,21 +1427,9 @@ analogix_dp_probe(struct device *dev, struct 
>> analogix_dp_plat_data *plat_data)
>>       if (ret)
>>           return ERR_PTR(ret);
>> -    dp->phy = devm_phy_get(dp->dev, "dp");
>> -    if (IS_ERR(dp->phy)) {
>> -        dev_err(dp->dev, "no DP phy configured\n");
>> -        ret = PTR_ERR(dp->phy);
>> -        if (ret) {
>> -            /*
>> -             * phy itself is not enabled, so we can move forward
>> -             * assigning NULL to phy pointer.
>> -             */
>> -            if (ret == -ENOSYS || ret == -ENODEV)
>> -                dp->phy = NULL;
>> -            else
>> -                return ERR_PTR(ret);
>> -        }
>> -    }
> 
> It should be better to add some comments here:
> 
> /*
>   * Exynos5/RK3288/RK3399 use Analogix DP controller built-in PHY,
>   * no separate PHY configuration is needed.
>   */

Well, I think it should be fixed to:

/*
  * RK3288/RK3399 use Analogix DP controller built-in PHY,
  * no extra PHY configuration is required.
  */

The Exynos5xxx case may be more complex.

> 
>> +    dp->phy = devm_phy_optional_get(dp->dev, "dp");
>> +    if (IS_ERR(dp->phy))
>> +        return ERR_CAST(dp->phy);
>>       dp->clock = devm_clk_get(&pdev->dev, "dp");
>>       if (IS_ERR(dp->clock)) {
> 
> With the comment added:
> Reviewed-by: Damon Ding <damon.ding@rock-chips.com>
> 
> Best regards,
> Damon
>