Re: [PATCH 3/3] drm/panel: ebbg-ft8719: Split initialization into enable/disable fn

[David Heidelberg <david@ixit.cz>]

On 08/09/2026 14:15, Neil Armstrong wrote:
> On 9/6/26 15:19, David Heidelberg via B4 Relay wrote:
>> From: David Heidelberg <david@ixit.cz>
>>
>> Efficiently this already happens with prepare/unprepare calls.
>> Remove unnecessary login and just use enable/disable functions.
> 
> I would replace with:
> 
> Move the MIPI commands into enable/disable callbacks since they
> are called between prepare/unprepare callbacks.
> 

I'll adjust.

> Or similar.
> 
>>
>> Signed-off-by: David Heidelberg <david@ixit.cz>
>> ---
>>   drivers/gpu/drm/panel/panel-ebbg-ft8719.c | 17 +++++++----------
>>   1 file changed, 7 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/panel/panel-ebbg-ft8719.c b/drivers/gpu/drm/ 
>> panel/panel-ebbg-ft8719.c
>> index 14982263a94f1..9965f46f1a316 100644
>> --- a/drivers/gpu/drm/panel/panel-ebbg-ft8719.c
>> +++ b/drivers/gpu/drm/panel/panel-ebbg-ft8719.c
>> @@ -49,40 +49,42 @@ static void ebbg_ft8719_reset(struct ebbg_ft8719 *ctx)
>>       gpiod_set_value_cansleep(ctx->reset_gpio, 0);
>>       usleep_range(4000, 5000);
>>       gpiod_set_value_cansleep(ctx->reset_gpio, 1);
>>       usleep_range(1000, 2000);
>>       gpiod_set_value_cansleep(ctx->reset_gpio, 0);
>>       usleep_range(15000, 16000);
>>   }
>> -static int ebbg_ft8719_on(struct ebbg_ft8719 *ctx)
>> +static int ebbg_ft8719_enable(struct drm_panel *panel)
>>   {
>> +    struct ebbg_ft8719 *ctx = to_ebbg_ft8719(panel);
>>       struct mipi_dsi_device *dsi = ctx->dsi;
>>       struct mipi_dsi_multi_context dsi_ctx = { .dsi = dsi };
>>       dsi->mode_flags |= MIPI_DSI_MODE_LPM;
>>       mipi_dsi_dcs_set_display_brightness_multi(&dsi_ctx, 0x00ff);
>>       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, MIPI_DCS_WRITE_CONTROL_DISPLAY, 
>> 0x24);
>>       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, MIPI_DCS_WRITE_POWER_SAVE, 0x00);
>>       mipi_dsi_dcs_exit_sleep_mode_multi(&dsi_ctx);
>>       mipi_dsi_msleep(&dsi_ctx, 90);
>>       mipi_dsi_dcs_set_display_on_multi(&dsi_ctx);
>>       return dsi_ctx.accum_err;
>>   }
>> -static int ebbg_ft8719_off(struct ebbg_ft8719 *ctx)
>> +static int ebbg_ft8719_disable(struct drm_panel *panel)
>>   {
>> +    struct ebbg_ft8719 *ctx = to_ebbg_ft8719(panel);
>>       struct mipi_dsi_device *dsi = ctx->dsi;
>>       struct mipi_dsi_multi_context dsi_ctx = { .dsi = dsi };
>> -    dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
>> +    ctx->dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
>>       mipi_dsi_dcs_set_display_off_multi(&dsi_ctx);
>>       mipi_dsi_usleep_range(&dsi_ctx, 10000, 11000);
>>       mipi_dsi_dcs_enter_sleep_mode_multi(&dsi_ctx);
>>       mipi_dsi_msleep(&dsi_ctx, 90);
>>       return dsi_ctx.accum_err;
> 
> Before the ebbg_ft8719_off() return error was ignored, perhaps you still want to 
> ignore the disable return error.

Sure, make sense. Next revision will land in minutes!
Thanks
David

> 
> Neil
> 
>>   }
>> @@ -93,30 +95,23 @@ static int ebbg_ft8719_prepare(struct drm_panel *panel)
>>       int ret;
>>       ret = regulator_bulk_enable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
>>       if (ret < 0)
>>           return ret;
>>       ebbg_ft8719_reset(ctx);
>> -    ret = ebbg_ft8719_on(ctx);
>> -    if (ret < 0) {
>> -        gpiod_set_value_cansleep(ctx->reset_gpio, 1);
>> -        return ret;
>> -    }
>> -
>>       return 0;
>>   }
>>   static int ebbg_ft8719_unprepare(struct drm_panel *panel)
>>   {
>>       struct ebbg_ft8719 *ctx = to_ebbg_ft8719(panel);
>> -    ebbg_ft8719_off(ctx);
>>       gpiod_set_value_cansleep(ctx->reset_gpio, 1);
>>       regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
>>       return 0;
>>   }
>>   static const struct drm_display_mode ebbg_ft8719_mode = {
>>       .clock = (1080 + 28 + 4 + 16) * (2246 + 120 + 4 + 12) * 60 / 1000,
>> @@ -148,16 +143,18 @@ static int ebbg_ft8719_get_modes(struct drm_panel *panel,
>>       connector->display_info.height_mm = mode->height_mm;
>>       drm_mode_probed_add(connector, mode);
>>       return 1;
>>   }
>>   static const struct drm_panel_funcs ebbg_ft8719_panel_funcs = {
>>       .prepare = ebbg_ft8719_prepare,
>> +    .enable = ebbg_ft8719_enable,
>> +    .disable = ebbg_ft8719_disable,
>>       .unprepare = ebbg_ft8719_unprepare,
>>       .get_modes = ebbg_ft8719_get_modes,
>>   };
>>   static int ebbg_ft8719_probe(struct mipi_dsi_device *dsi)
>>   {
>>       struct device *dev = &dsi->dev;
>>       struct ebbg_ft8719 *ctx;
>>
>