[PATCH v17 6/7] drm/rockchip: cdn-dp: retry to check sink count

Chris Zhong
2017-02-05T07:55:01Z

Sometimes the Dock is disconnected, but cdn_dp_encoder_disable is not
triggered by DRM. For example, unplug the Dock in console mode, and
re-plug it again, the cdn_dp_event_work will try to get the sink count
of Dock, since the DP is still active. But the Dock has been powered
down, it need re-power on, and wait for a while until it is ready to
DPCD communication.

Signed-off-by: Chris Zhong <zyw@rock-chips.com>
---

Changes in v17: None

drivers/gpu/drm/rockchip/cdn-dp-core.c | 91 +++++++++++++++++++---------------
drivers/gpu/drm/rockchip/cdn-dp-core.h | 1 +
2 files changed, 52 insertions(+), 40 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/cdn-dp-core.c b/drivers/gpu/drm/rockchip/cdn-dp-core.c
index 799e826..a630b0d 100644
--- a/drivers/gpu/drm/rockchip/cdn-dp-core.c
+++ b/drivers/gpu/drm/rockchip/cdn-dp-core.c
@@ -197,6 +197,39 @@ static struct cdn_dp_port *cdn_dp_connected_port(struct cdn_dp_device *dp)
return NULL;
}

+static bool cdn_dp_check_sink_connection(struct cdn_dp_device *dp)
+{
+ unsigned long timeout = jiffies + msecs_to_jiffies(CDN_DPCD_TIMEOUT_MS);
+ struct cdn_dp_port *port;
+ u8 sink_count = 0;
+
+ if (dp->active_port < 0 || dp->active_port >= dp->ports) {
+ DRM_DEV_ERROR(dp->dev, "active_port is wrong!\n");
+ return false;
+ }
+
+ port = dp->port[dp->active_port];
+
+ /*
+ * Attempt to read sink count, retry in case the sink may not be ready.
+ *
+ * Sinks are *supposed* to come up within 1ms from an off state, but
+ * some docks need more time to power up.
+ */
+ while (time_before(jiffies, timeout)) {
+ if (!extcon_get_state(port->extcon, EXTCON_DISP_DP))
+ return false;
+
+ if (!cdn_dp_get_sink_count(dp, &sink_count))
+ return sink_count ? true : false;
+
+ usleep_range(5000, 10000);
+ }
+
+ DRM_DEV_ERROR(dp->dev, "Get sink capability timed out\n");
+ return false;
+}
+
static enum drm_connector_status
cdn_dp_connector_detect(struct drm_connector *connector, bool force)
{
@@ -345,47 +378,24 @@ static int cdn_dp_firmware_init(struct cdn_dp_device *dp)
return cdn_dp_event_config(dp);
}

-static int cdn_dp_get_sink_capability(struct cdn_dp_device *dp,
- struct cdn_dp_port *port,
- u8 *sink_count)
+static int cdn_dp_get_sink_capability(struct cdn_dp_device *dp)
{
int ret;
- unsigned long timeout = jiffies + msecs_to_jiffies(CDN_DPCD_TIMEOUT_MS);

- /*
- * Attempt to read sink count & sink capability, retry in case the sink
- * may not be ready.
- *
- * Sinks are *supposed* to come up within 1ms from an off state, but
- * some docks need more time to power up.
- */
- while (time_before(jiffies, timeout)) {
- if (!extcon_get_state(port->extcon, EXTCON_DISP_DP))
- return -ENODEV;
-
- if (cdn_dp_get_sink_count(dp, sink_count)) {
- usleep_range(5000, 10000);
- continue;
- }
-
- if (!*sink_count)
- return -ENODEV;
-
- ret = cdn_dp_dpcd_read(dp, DP_DPCD_REV, dp->dpcd,
- DP_RECEIVER_CAP_SIZE);
- if (ret) {
- DRM_DEV_ERROR(dp->dev, "Failed to get caps %d\n", ret);
- return ret;
- }
+ if (!cdn_dp_check_sink_connection(dp))
+ return -ENODEV;

- kfree(dp->edid);
- dp->edid = drm_do_get_edid(&dp->connector,
- cdn_dp_get_edid_block, dp);
- return 0;
+ ret = cdn_dp_dpcd_read(dp, DP_DPCD_REV, dp->dpcd,
+ DP_RECEIVER_CAP_SIZE);
+ if (ret) {
+ DRM_DEV_ERROR(dp->dev, "Failed to get caps %d\n", ret);
+ return ret;
}

- DRM_DEV_ERROR(dp->dev, "Get sink capability timed out\n");
- return -ETIMEDOUT;
+ kfree(dp->edid);
+ dp->edid = drm_do_get_edid(&dp->connector,
+ cdn_dp_get_edid_block, dp);
+ return 0;
}

static int cdn_dp_enable_phy(struct cdn_dp_device *dp, struct cdn_dp_port *port)
@@ -437,6 +447,7 @@ static int cdn_dp_enable_phy(struct cdn_dp_device *dp, struct cdn_dp_port *port)
goto err_power_on;
}

+ dp->active_port = port->id;
return 0;

err_power_on:
@@ -466,6 +477,7 @@ static int cdn_dp_disable_phy(struct cdn_dp_device *dp,

port->phy_enabled = false;
port->lanes = 0;
+ dp->active_port = -1;
return 0;
}

@@ -504,7 +516,6 @@ static int cdn_dp_enable(struct cdn_dp_device *dp)
{
int ret, i, lanes;
struct cdn_dp_port *port;
- u8 sink_count;

port = cdn_dp_connected_port(dp);
if (!port) {
@@ -535,8 +546,8 @@ static int cdn_dp_enable(struct cdn_dp_device *dp)
if (ret)
continue;

- ret = cdn_dp_get_sink_capability(dp, port, &sink_count);
- if (ret || (!ret && !sink_count)) {
+ ret = cdn_dp_get_sink_capability(dp);
+ if (ret) {
cdn_dp_disable_phy(dp, port);
} else {
dp->active = true;
@@ -939,7 +950,6 @@ static void cdn_dp_pd_event_work(struct work_struct *work)
enum drm_connector_status old_status;

int ret;
- u8 sink_count;

mutex_lock(&dp->lock);

@@ -967,7 +977,7 @@ static void cdn_dp_pd_event_work(struct work_struct *work)
}

/* Enabled and connected to a dongle without a sink, notify userspace */
- } else if (cdn_dp_get_sink_count(dp, &sink_count) || !sink_count) {
+ } else if (!cdn_dp_check_sink_connection(dp)) {
DRM_DEV_INFO(dp->dev, "Connected without sink. Assert hpd\n");
dp->connected = false;

@@ -1040,6 +1050,7 @@ static int cdn_dp_bind(struct device *dev, struct device *master, void *data)
dp->drm_dev = drm_dev;
dp->connected = false;
dp->active = false;
+ dp->active_port = -1;

INIT_WORK(&dp->event_work, cdn_dp_pd_event_work);

diff --git a/drivers/gpu/drm/rockchip/cdn-dp-core.h b/drivers/gpu/drm/rockchip/cdn-dp-core.h
index 7d48661..f57e296 100644
--- a/drivers/gpu/drm/rockchip/cdn-dp-core.h
+++ b/drivers/gpu/drm/rockchip/cdn-dp-core.h
@@ -104,6 +104,7 @@ struct cdn_dp_device {
struct cdn_dp_port *port[MAX_PHY];
u8 ports;
u8 lanes;
+ int active_port;

u8 dpcd[DP_RECEIVER_CAP_SIZE];
bool sink_has_audio;
--
2.6.3