Move the DPCD read and link setup steps to HPD IRQ handler to remove
an unnecessary dependency between .detect callback and the HPD IRQ
handler before registering it6505 as a DRM bridge. This is safe because
there is always a .detect call after each HPD IRQ handler triggered by
the drm_helper_hpd_irq_event call.
Signed-off-by: Pin-yen Lin <[email protected]>
---
Changes in v2:
- Remove redundant spaces in it6505_detect
- Read sink count in it6505_irq_hpd
drivers/gpu/drm/bridge/ite-it6505.c | 80 +++++++++++++----------------
1 file changed, 35 insertions(+), 45 deletions(-)
diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
index f7f6c3e20fae..4b6061272599 100644
--- a/drivers/gpu/drm/bridge/ite-it6505.c
+++ b/drivers/gpu/drm/bridge/ite-it6505.c
@@ -725,28 +725,6 @@ static void it6505_calc_video_info(struct it6505 *it6505)
DRM_MODE_ARG(&it6505->video_info));
}
-static int it6505_drm_dp_link_probe(struct drm_dp_aux *aux,
- struct it6505_drm_dp_link *link)
-{
- u8 values[3];
- int err;
-
- memset(link, 0, sizeof(*link));
-
- err = drm_dp_dpcd_read(aux, DP_DPCD_REV, values, sizeof(values));
- if (err < 0)
- return err;
-
- link->revision = values[0];
- link->rate = drm_dp_bw_code_to_link_rate(values[1]);
- link->num_lanes = values[2] & DP_MAX_LANE_COUNT_MASK;
-
- if (values[2] & DP_ENHANCED_FRAME_CAP)
- link->capabilities = DP_ENHANCED_FRAME_CAP;
-
- return 0;
-}
-
static int it6505_drm_dp_link_set_power(struct drm_dp_aux *aux,
struct it6505_drm_dp_link *link,
u8 mode)
@@ -1456,11 +1434,19 @@ static void it6505_parse_link_capabilities(struct it6505 *it6505)
int bcaps;
if (it6505->dpcd[0] == 0) {
- it6505_aux_on(it6505);
- it6505_get_dpcd(it6505, DP_DPCD_REV, it6505->dpcd,
- ARRAY_SIZE(it6505->dpcd));
+ dev_err(dev, "DPCD is not initialized");
+ return;
}
+ memset(link, 0, sizeof(*link));
+
+ link->revision = it6505->dpcd[0];
+ link->rate = drm_dp_bw_code_to_link_rate(it6505->dpcd[1]);
+ link->num_lanes = it6505->dpcd[2] & DP_MAX_LANE_COUNT_MASK;
+
+ if (it6505->dpcd[2] & DP_ENHANCED_FRAME_CAP)
+ link->capabilities = DP_ENHANCED_FRAME_CAP;
+
DRM_DEV_DEBUG_DRIVER(dev, "DPCD Rev.: %d.%d",
link->revision >> 4, link->revision & 0x0F);
@@ -2323,19 +2309,32 @@ static int it6505_process_hpd_irq(struct it6505 *it6505)
static void it6505_irq_hpd(struct it6505 *it6505)
{
struct device *dev = &it6505->client->dev;
+ int dp_sink_count;
it6505->hpd_state = it6505_get_sink_hpd_status(it6505);
DRM_DEV_DEBUG_DRIVER(dev, "hpd change interrupt, change to %s",
it6505->hpd_state ? "high" : "low");
- if (it6505->bridge.dev)
- drm_helper_hpd_irq_event(it6505->bridge.dev);
- DRM_DEV_DEBUG_DRIVER(dev, "it6505->sink_count: %d",
- it6505->sink_count);
-
if (it6505->hpd_state) {
wait_for_completion_timeout(&it6505->wait_edid_complete,
msecs_to_jiffies(6000));
+ it6505_aux_on(it6505);
+ if (it6505->dpcd[0] == 0) {
+ it6505_get_dpcd(it6505, DP_DPCD_REV, it6505->dpcd,
+ ARRAY_SIZE(it6505->dpcd));
+ it6505_variable_config(it6505);
+ it6505_parse_link_capabilities(it6505);
+ }
+ it6505->auto_train_retry = AUTO_TRAIN_RETRY;
+
+ it6505_drm_dp_link_set_power(&it6505->aux, &it6505->link,
+ DP_SET_POWER_D0);
+ dp_sink_count = it6505_dpcd_read(it6505, DP_SINK_COUNT);
+ it6505->sink_count = DP_GET_SINK_COUNT(dp_sink_count);
+
+ DRM_DEV_DEBUG_DRIVER(dev, "it6505->sink_count: %d",
+ it6505->sink_count);
+
it6505_lane_termination_on(it6505);
it6505_lane_power_on(it6505);
@@ -2363,6 +2362,9 @@ static void it6505_irq_hpd(struct it6505 *it6505)
it6505_lane_off(it6505);
it6505_link_reset_step_train(it6505);
}
+
+ if (it6505->bridge.dev)
+ drm_helper_hpd_irq_event(it6505->bridge.dev);
}
static void it6505_irq_hpd_irq(struct it6505 *it6505)
@@ -2625,26 +2627,14 @@ static enum drm_connector_status it6505_detect(struct it6505 *it6505)
goto unlock;
if (it6505->enable_drv_hold) {
- status = it6505_get_sink_hpd_status(it6505) ?
- connector_status_connected :
- connector_status_disconnected;
+ status = it6505->hpd_state ? connector_status_connected :
+ connector_status_disconnected;
goto unlock;
}
- if (it6505_get_sink_hpd_status(it6505)) {
- it6505_aux_on(it6505);
- it6505_drm_dp_link_probe(&it6505->aux, &it6505->link);
+ if (it6505->hpd_state) {
it6505_drm_dp_link_set_power(&it6505->aux, &it6505->link,
DP_SET_POWER_D0);
- it6505->auto_train_retry = AUTO_TRAIN_RETRY;
-
- if (it6505->dpcd[0] == 0) {
- it6505_get_dpcd(it6505, DP_DPCD_REV, it6505->dpcd,
- ARRAY_SIZE(it6505->dpcd));
- it6505_variable_config(it6505);
- it6505_parse_link_capabilities(it6505);
- }
-
dp_sink_count = it6505_dpcd_read(it6505, DP_SINK_COUNT);
it6505->sink_count = DP_GET_SINK_COUNT(dp_sink_count);
DRM_DEV_DEBUG_DRIVER(dev, "it6505->sink_count:%d branch:%d",
--
2.38.0.rc1.362.ged0d419d3c-goog
On Thu, 13 Oct 2022 at 13:04, Pin-yen Lin <[email protected]> wrote:
>
> Move the DPCD read and link setup steps to HPD IRQ handler to remove
> an unnecessary dependency between .detect callback and the HPD IRQ
> handler before registering it6505 as a DRM bridge. This is safe because
> there is always a .detect call after each HPD IRQ handler triggered by
> the drm_helper_hpd_irq_event call.
>
> Signed-off-by: Pin-yen Lin <[email protected]>
> ---
>
> Changes in v2:
> - Remove redundant spaces in it6505_detect
> - Read sink count in it6505_irq_hpd
>
> drivers/gpu/drm/bridge/ite-it6505.c | 80 +++++++++++++----------------
> 1 file changed, 35 insertions(+), 45 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
> index f7f6c3e20fae..4b6061272599 100644
> --- a/drivers/gpu/drm/bridge/ite-it6505.c
> +++ b/drivers/gpu/drm/bridge/ite-it6505.c
> @@ -725,28 +725,6 @@ static void it6505_calc_video_info(struct it6505 *it6505)
> DRM_MODE_ARG(&it6505->video_info));
> }
>
> -static int it6505_drm_dp_link_probe(struct drm_dp_aux *aux,
> - struct it6505_drm_dp_link *link)
> -{
> - u8 values[3];
> - int err;
> -
> - memset(link, 0, sizeof(*link));
> -
> - err = drm_dp_dpcd_read(aux, DP_DPCD_REV, values, sizeof(values));
> - if (err < 0)
> - return err;
> -
> - link->revision = values[0];
> - link->rate = drm_dp_bw_code_to_link_rate(values[1]);
> - link->num_lanes = values[2] & DP_MAX_LANE_COUNT_MASK;
> -
> - if (values[2] & DP_ENHANCED_FRAME_CAP)
> - link->capabilities = DP_ENHANCED_FRAME_CAP;
> -
> - return 0;
> -}
> -
> static int it6505_drm_dp_link_set_power(struct drm_dp_aux *aux,
> struct it6505_drm_dp_link *link,
> u8 mode)
> @@ -1456,11 +1434,19 @@ static void it6505_parse_link_capabilities(struct it6505 *it6505)
> int bcaps;
>
> if (it6505->dpcd[0] == 0) {
> - it6505_aux_on(it6505);
> - it6505_get_dpcd(it6505, DP_DPCD_REV, it6505->dpcd,
> - ARRAY_SIZE(it6505->dpcd));
> + dev_err(dev, "DPCD is not initialized");
> + return;
> }
>
> + memset(link, 0, sizeof(*link));
> +
> + link->revision = it6505->dpcd[0];
> + link->rate = drm_dp_bw_code_to_link_rate(it6505->dpcd[1]);
> + link->num_lanes = it6505->dpcd[2] & DP_MAX_LANE_COUNT_MASK;
> +
> + if (it6505->dpcd[2] & DP_ENHANCED_FRAME_CAP)
> + link->capabilities = DP_ENHANCED_FRAME_CAP;
> +
> DRM_DEV_DEBUG_DRIVER(dev, "DPCD Rev.: %d.%d",
> link->revision >> 4, link->revision & 0x0F);
>
> @@ -2323,19 +2309,32 @@ static int it6505_process_hpd_irq(struct it6505 *it6505)
> static void it6505_irq_hpd(struct it6505 *it6505)
> {
> struct device *dev = &it6505->client->dev;
> + int dp_sink_count;
>
> it6505->hpd_state = it6505_get_sink_hpd_status(it6505);
> DRM_DEV_DEBUG_DRIVER(dev, "hpd change interrupt, change to %s",
> it6505->hpd_state ? "high" : "low");
>
> - if (it6505->bridge.dev)
> - drm_helper_hpd_irq_event(it6505->bridge.dev);
> - DRM_DEV_DEBUG_DRIVER(dev, "it6505->sink_count: %d",
> - it6505->sink_count);
> -
> if (it6505->hpd_state) {
> wait_for_completion_timeout(&it6505->wait_edid_complete,
> msecs_to_jiffies(6000));
> + it6505_aux_on(it6505);
> + if (it6505->dpcd[0] == 0) {
> + it6505_get_dpcd(it6505, DP_DPCD_REV, it6505->dpcd,
> + ARRAY_SIZE(it6505->dpcd));
> + it6505_variable_config(it6505);
> + it6505_parse_link_capabilities(it6505);
> + }
> + it6505->auto_train_retry = AUTO_TRAIN_RETRY;
> +
> + it6505_drm_dp_link_set_power(&it6505->aux, &it6505->link,
> + DP_SET_POWER_D0);
> + dp_sink_count = it6505_dpcd_read(it6505, DP_SINK_COUNT);
> + it6505->sink_count = DP_GET_SINK_COUNT(dp_sink_count);
> +
> + DRM_DEV_DEBUG_DRIVER(dev, "it6505->sink_count: %d",
> + it6505->sink_count);
> +
> it6505_lane_termination_on(it6505);
> it6505_lane_power_on(it6505);
>
> @@ -2363,6 +2362,9 @@ static void it6505_irq_hpd(struct it6505 *it6505)
> it6505_lane_off(it6505);
> it6505_link_reset_step_train(it6505);
> }
> +
> + if (it6505->bridge.dev)
> + drm_helper_hpd_irq_event(it6505->bridge.dev);
> }
>
> static void it6505_irq_hpd_irq(struct it6505 *it6505)
> @@ -2625,26 +2627,14 @@ static enum drm_connector_status it6505_detect(struct it6505 *it6505)
> goto unlock;
>
> if (it6505->enable_drv_hold) {
> - status = it6505_get_sink_hpd_status(it6505) ?
> - connector_status_connected :
> - connector_status_disconnected;
> + status = it6505->hpd_state ? connector_status_connected :
> + connector_status_disconnected;
> goto unlock;
> }
>
> - if (it6505_get_sink_hpd_status(it6505)) {
> - it6505_aux_on(it6505);
> - it6505_drm_dp_link_probe(&it6505->aux, &it6505->link);
> + if (it6505->hpd_state) {
> it6505_drm_dp_link_set_power(&it6505->aux, &it6505->link,
> DP_SET_POWER_D0);
> - it6505->auto_train_retry = AUTO_TRAIN_RETRY;
> -
> - if (it6505->dpcd[0] == 0) {
> - it6505_get_dpcd(it6505, DP_DPCD_REV, it6505->dpcd,
> - ARRAY_SIZE(it6505->dpcd));
> - it6505_variable_config(it6505);
> - it6505_parse_link_capabilities(it6505);
> - }
> -
> dp_sink_count = it6505_dpcd_read(it6505, DP_SINK_COUNT);
> it6505->sink_count = DP_GET_SINK_COUNT(dp_sink_count);
> DRM_DEV_DEBUG_DRIVER(dev, "it6505->sink_count:%d branch:%d",
> --
> 2.38.0.rc1.362.ged0d419d3c-goog
>
Reviewed-by: Robert Foss <[email protected]>