Re: [PATCH v2 12/13] drm/bridge: lt9611: stop filtering modes via the table

[neil.armstrong@linaro.org]

On 11/01/2023 16:37, Dmitry Baryshkov wrote:
> On 11/01/2023 12:57, Neil Armstrong wrote:
>> On 08/01/2023 17:56, Dmitry Baryshkov wrote:
>>> The lt9611 bridge can support different modes, it makes no sense to list
>>> them in the table. Drop the table and check the number of interfaces
>>> using the fixed value.
>>>
>>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>>> ---
>>>   drivers/gpu/drm/bridge/lontium-lt9611.c | 41 +++----------------------
>>>   1 file changed, 4 insertions(+), 37 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/bridge/lontium-lt9611.c b/drivers/gpu/drm/bridge/lontium-lt9611.c
>>> index 82af1f954cc6..df9f015aa3a0 100644
>>> --- a/drivers/gpu/drm/bridge/lontium-lt9611.c
>>> +++ b/drivers/gpu/drm/bridge/lontium-lt9611.c
>>> @@ -84,24 +84,6 @@ static const struct regmap_config lt9611_regmap_config = {
>>>       .num_ranges = ARRAY_SIZE(lt9611_ranges),
>>>   };
>>> -struct lt9611_mode {
>>> -    u16 hdisplay;
>>> -    u16 vdisplay;
>>> -    u8 vrefresh;
>>> -    u8 lanes;
>>> -    u8 intfs;
>>> -};
>>> -
>>> -static struct lt9611_mode lt9611_modes[] = {
>>> -    { 3840, 2160, 30, 4, 2 }, /* 3840x2160 24bit 30Hz 4Lane 2ports */
>>> -    { 1920, 1080, 60, 4, 1 }, /* 1080P 24bit 60Hz 4lane 1port */
>>> -    { 1920, 1080, 30, 3, 1 }, /* 1080P 24bit 30Hz 3lane 1port */
>>> -    { 1920, 1080, 24, 3, 1 },
>>> -    { 720, 480, 60, 4, 1 },
>>> -    { 720, 576, 50, 2, 1 },
>>> -    { 640, 480, 60, 2, 1 },
>>> -};
>>> -
>>>   static struct lt9611 *bridge_to_lt9611(struct drm_bridge *bridge)
>>>   {
>>>       return container_of(bridge, struct lt9611, bridge);
>>> @@ -603,21 +585,6 @@ static int lt9611_regulator_enable(struct lt9611 *lt9611)
>>>       return 0;
>>>   }
>>> -static struct lt9611_mode *lt9611_find_mode(const struct drm_display_mode *mode)
>>> -{
>>> -    int i;
>>> -
>>> -    for (i = 0; i < ARRAY_SIZE(lt9611_modes); i++) {
>>> -        if (lt9611_modes[i].hdisplay == mode->hdisplay &&
>>> -            lt9611_modes[i].vdisplay == mode->vdisplay &&
>>> -            lt9611_modes[i].vrefresh == drm_mode_vrefresh(mode)) {
>>> -            return &lt9611_modes[i];
>>> -        }
>>> -    }
>>> -
>>> -    return NULL;
>>> -}
>>> -
>>>   static enum drm_connector_status lt9611_bridge_detect(struct drm_bridge *bridge)
>>>   {
>>>       struct lt9611 *lt9611 = bridge_to_lt9611(bridge);
>>> @@ -832,12 +799,12 @@ static enum drm_mode_status lt9611_bridge_mode_valid(struct drm_bridge *bridge,
>>>                                const struct drm_display_info *info,
>>>                                const struct drm_display_mode *mode)
>>>   {
>>> -    struct lt9611_mode *lt9611_mode = lt9611_find_mode(mode);
>>>       struct lt9611 *lt9611 = bridge_to_lt9611(bridge);
>>> -    if (!lt9611_mode)
>>> -        return MODE_BAD;
>>> -    else if (lt9611_mode->intfs > 1 && !lt9611->dsi1)
>>> +    if (mode->hdisplay >= 3840 && drm_mode_vrefresh(mode) >= 31)
>>
>> Isn't 31 a typo ?
> 
> Maybe I should change that to drm_mode_vrefresh(mode) > 30. The chip supports 3840x2160-30, but doesn't promise to support anything above that.

Yep >= 31 is valid, but > 30 seems more logical.

Concerning the hdisplay check, shouldn't be separate ?

You should switch to:
if (mode->hdisplay > 3840)
    return MODE_BAD_WIDTH;

if (mode->hdisplay == 3840 && drm_mode_vrefresh(mode) > 30)
    return MODE_CLOCK_HIGH;

Isn't there limits on vdisplay aswell ?

Neil

> 
>>
>>> +        return MODE_CLOCK_HIGH;
>>> +
>>> +    if (mode->hdisplay > 2000 && !lt9611->dsi1_node)
>>>           return MODE_PANEL;
>>>       else
>>>           return MODE_OK;
>>
>