On Wed, Aug 30, 2023 at 4:25 PM Biju Das <biju.das.jz@xxxxxxxxxxxxxx> wrote:
>
> As per spec, it is allowed to pulse the HPD signal to indicate that the
> EDID information has changed. Some monitors do this when they wake up
> from standby or are enabled. When the HPD goes low the adv7511 is
> reset and the outputs are disabled which might cause the monitor to
> go to standby again. To avoid this we ignore the HPD pin for the
> first few seconds after enabling the output. On the other hand,
> adv7535 require to enable HPD Override bit for proper HPD.
>
> Add hpd_override_enable variable to struct adv7511_chip_info to handle
> this scenario.
>
> Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> ---
> v1->v2:
> * Restored enum adv7511_type as there are users.
> * Replaced variable type from unsigned->bool.
> ---
> drivers/gpu/drm/bridge/adv7511/adv7511.h | 1 +
> drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 7 ++++---
> 2 files changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511.h b/drivers/gpu/drm/bridge/adv7511/adv7511.h
> index 0d39e32b0793..39c9ece373b0 100644
> --- a/drivers/gpu/drm/bridge/adv7511/adv7511.h
> +++ b/drivers/gpu/drm/bridge/adv7511/adv7511.h
> @@ -342,6 +342,7 @@ struct adv7511_chip_info {
> unsigned int reg_cec_offset;
> bool has_dsi;
> bool link_config;
> + bool hpd_override_enable;
> };
>
> struct adv7511 {
> diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> index e0ec3c098225..83ff4206b3b7 100644
> --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> @@ -354,7 +354,7 @@ static void __adv7511_power_on(struct adv7511 *adv7511)
> * first few seconds after enabling the output. On the other hand
> * adv7535 require to enable HPD Override bit for proper HPD.
> */
> - if (adv7511->info->type == ADV7535)
> + if (adv7511->info->hpd_override_enable)
> regmap_update_bits(adv7511->regmap, ADV7511_REG_POWER2,
> ADV7535_REG_POWER2_HPD_OVERRIDE,
> ADV7535_REG_POWER2_HPD_OVERRIDE);
> @@ -381,7 +381,7 @@ static void adv7511_power_on(struct adv7511 *adv7511)
> static void __adv7511_power_off(struct adv7511 *adv7511)
> {
> /* TODO: setup additional power down modes */
> - if (adv7511->info->type == ADV7535)
> + if (adv7511->info->hpd_override_enable)
> regmap_update_bits(adv7511->regmap, ADV7511_REG_POWER2,
> ADV7535_REG_POWER2_HPD_OVERRIDE, 0);
>
> @@ -682,7 +682,7 @@ adv7511_detect(struct adv7511 *adv7511, struct drm_connector *connector)
> status = connector_status_disconnected;
> } else {
> /* Renable HPD sensing */
> - if (adv7511->info->type == ADV7535)
> + if (adv7511->info->hpd_override_enable)
> regmap_update_bits(adv7511->regmap, ADV7511_REG_POWER2,
> ADV7535_REG_POWER2_HPD_OVERRIDE,
> ADV7535_REG_POWER2_HPD_OVERRIDE);
> @@ -1379,6 +1379,7 @@ static const struct adv7511_chip_info adv7535_chip_info = {
> .num_supplies = ARRAY_SIZE(adv7533_supply_names),
> .reg_cec_offset = ADV7533_REG_CEC_OFFSET,
> .has_dsi = true,
> + .hpd_override_enable = true,
> };
>
> static const struct i2c_device_id adv7511_i2c_ids[] = {
> --
> 2.25.1
Reviewed-by: Robert Foss <rfoss@xxxxxxxxxx>
