From: Rahul T R <r-ravikumar@xxxxxx>
In J721S2 EVMs DP0 hpd is not connected to correct
hpd pin on SOC, to handle such cases, Add support for
"no-hpd" property in the device tree node to disable
hpd
Also change the log level for dpcd read failuers to
debug, since framework retries 32 times for each read
Signed-off-by: Rahul T R <r-ravikumar@xxxxxx>
Signed-off-by: Jayesh Choudhary <j-choudhary@xxxxxx>
---
.../drm/bridge/cadence/cdns-mhdp8546-core.c | 37 ++++++++++++++++---
.../drm/bridge/cadence/cdns-mhdp8546-core.h | 1 +
2 files changed, 33 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
index f6822dfa3805..e177794b069d 100644
--- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
+++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
@@ -54,6 +54,8 @@
#include "cdns-mhdp8546-hdcp.h"
#include "cdns-mhdp8546-j721e.h"
+static int cdns_mhdp_update_link_status(struct cdns_mhdp_device *mhdp);
+
static int cdns_mhdp_mailbox_read(struct cdns_mhdp_device *mhdp)
{
int ret, empty;
@@ -749,7 +751,7 @@ static int cdns_mhdp_fw_activate(const struct firmware *fw,
* MHDP_HW_STOPPED happens only due to driver removal when
* bridge should already be detached.
*/
- if (mhdp->bridge_attached)
+ if (mhdp->bridge_attached && !mhdp->no_hpd)
writel(~(u32)CDNS_APB_INT_MASK_SW_EVENT_INT,
mhdp->regs + CDNS_APB_INT_MASK);
@@ -845,7 +847,7 @@ static ssize_t cdns_mhdp_transfer(struct drm_dp_aux *aux,
ret = cdns_mhdp_dpcd_read(mhdp, msg->address,
msg->buffer, msg->size);
if (ret) {
- dev_err(mhdp->dev,
+ dev_dbg(mhdp->dev,
"Failed to read DPCD addr %u\n",
msg->address);
@@ -1738,6 +1740,19 @@ static int cdns_mhdp_attach(struct drm_bridge *bridge,
spin_unlock(&mhdp->start_lock);
+ if (mhdp->no_hpd) {
+ ret = wait_event_timeout(mhdp->fw_load_wq,
+ mhdp->hw_state == MHDP_HW_READY,
+ msecs_to_jiffies(100));
+ if (ret == 0) {
+ dev_err(mhdp->dev, "%s: Timeout waiting for fw loading\n",
+ __func__);
+ return -ETIMEDOUT;
+ }
+
+ cdns_mhdp_update_link_status(mhdp);
+ return 0;
+ }
/* Enable SW event interrupts */
if (hw_ready)
writel(~(u32)CDNS_APB_INT_MASK_SW_EVENT_INT,
@@ -2256,7 +2271,16 @@ static int cdns_mhdp_update_link_status(struct cdns_mhdp_device *mhdp)
mutex_lock(&mhdp->link_mutex);
- mhdp->plugged = cdns_mhdp_detect_hpd(mhdp, &hpd_pulse);
+ if (mhdp->no_hpd) {
+ ret = drm_dp_dpcd_read_link_status(&mhdp->aux, status);
+ hpd_pulse = false;
+ if (ret < 0)
+ mhdp->plugged = false;
+ else
+ mhdp->plugged = true;
+ } else {
+ mhdp->plugged = cdns_mhdp_detect_hpd(mhdp, &hpd_pulse);
+ }
if (!mhdp->plugged) {
cdns_mhdp_link_down(mhdp);
@@ -2451,6 +2475,8 @@ static int cdns_mhdp_probe(struct platform_device *pdev)
mhdp->aux.dev = dev;
mhdp->aux.transfer = cdns_mhdp_transfer;
+ mhdp->no_hpd = of_property_read_bool(dev->of_node, "cdns,no-hpd");
+
mhdp->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(mhdp->regs)) {
dev_err(dev, "Failed to get memory resource\n");
@@ -2526,8 +2552,9 @@ static int cdns_mhdp_probe(struct platform_device *pdev)
mhdp->bridge.of_node = pdev->dev.of_node;
mhdp->bridge.funcs = &cdns_mhdp_bridge_funcs;
- mhdp->bridge.ops = DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID |
- DRM_BRIDGE_OP_HPD;
+ mhdp->bridge.ops = DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID;
+ if (!mhdp->no_hpd)
+ mhdp->bridge.ops |= DRM_BRIDGE_OP_HPD;
mhdp->bridge.type = DRM_MODE_CONNECTOR_DisplayPort;
if (mhdp->info)
mhdp->bridge.timings = mhdp->info->timings;
diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.h b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.h
index bedddd510d17..6786ccb51387 100644
--- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.h
+++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.h
@@ -388,6 +388,7 @@ struct cdns_mhdp_device {
bool link_up;
bool plugged;
+ bool no_hpd;
/*
* "start_lock" protects the access to bridge_attached and
--
2.25.1
