[PATCH 8/9] usb: typec: altmodes/displayport: Notify drm subsys of hotplug events

Hans de Goede
2021-05-03T15:47:28Z

Use the new drm_connector_find_by_fwnode() and
drm_connector_oob_hotplug_event() functions to let drm/kms drivers
know about DisplayPort over Type-C hotplug events.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Changes in v2:
- Add missing depends on DRM to TYPEC_DP_ALTMODE Kconfig entry
---
drivers/usb/typec/altmodes/Kconfig | 1 +
drivers/usb/typec/altmodes/displayport.c | 40 +++++++++++++++++++++++-
2 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/typec/altmodes/Kconfig b/drivers/usb/typec/altmodes/Kconfig
index 60d375e9c3c7..1a6b5e872b0d 100644
--- a/drivers/usb/typec/altmodes/Kconfig
+++ b/drivers/usb/typec/altmodes/Kconfig
@@ -4,6 +4,7 @@ menu "USB Type-C Alternate Mode drivers"

config TYPEC_DP_ALTMODE
tristate "DisplayPort Alternate Mode driver"
+ depends on DRM
help
DisplayPort USB Type-C Alternate Mode allows DisplayPort
displays and adapters to be attached to the USB Type-C
diff --git a/drivers/usb/typec/altmodes/displayport.c b/drivers/usb/typec/altmodes/displayport.c
index aa669b9cf70e..f00dfc5c14b6 100644
--- a/drivers/usb/typec/altmodes/displayport.c
+++ b/drivers/usb/typec/altmodes/displayport.c
@@ -11,8 +11,10 @@
#include <linux/delay.h>
#include <linux/mutex.h>
#include <linux/module.h>
+#include <linux/property.h>
#include <linux/usb/pd_vdo.h>
#include <linux/usb/typec_dp.h>
+#include <drm/drm_connector.h>
#include "displayport.h"

#define DP_HEADER(_dp, ver, cmd) (VDO((_dp)->alt->svid, 1, ver, cmd) \
@@ -62,12 +64,30 @@ struct dp_altmode {
struct work_struct work;
struct typec_altmode *alt;
const struct typec_altmode *port;
+ struct fwnode_handle *connector_fwnode;
};

+static void dp_altmode_notify_connector(struct dp_altmode *dp)
+{
+ struct drm_connector_oob_hotplug_event_data data = { };
+ u8 pin_assign = DP_CONF_GET_PIN_ASSIGN(dp->data.conf);
+
+ data.connected = dp->data.status & DP_STATUS_HPD_STATE;
+ data.orientation = typec_altmode_get_orientation(dp->alt);
+
+ if (pin_assign & DP_PIN_ASSIGN_DP_ONLY_MASK)
+ data.dp_lanes = 4;
+ else if (pin_assign & DP_PIN_ASSIGN_MULTI_FUNC_MASK)
+ data.dp_lanes = 2;
+
+ drm_connector_oob_hotplug_event(dp->connector_fwnode, &data);
+}
+
static int dp_altmode_notify(struct dp_altmode *dp)
{
unsigned long conf;
u8 state;
+ int ret;

if (dp->data.conf) {
state = get_count_order(DP_CONF_GET_PIN_ASSIGN(dp->data.conf));
@@ -76,7 +96,12 @@ static int dp_altmode_notify(struct dp_altmode *dp)
conf = TYPEC_STATE_USB;
}

- return typec_altmode_notify(dp->alt, conf, &dp->data);
+ ret = typec_altmode_notify(dp->alt, conf, &dp->data);
+ if (ret)
+ return ret;
+
+ dp_altmode_notify_connector(dp);
+ return 0;
}

static int dp_altmode_configure(struct dp_altmode *dp, u8 con)
@@ -512,6 +537,7 @@ static const struct attribute_group dp_altmode_group = {
int dp_altmode_probe(struct typec_altmode *alt)
{
const struct typec_altmode *port = typec_altmode_get_partner(alt);
+ struct fwnode_handle *fwnode;
struct dp_altmode *dp;
int ret;

@@ -540,6 +566,11 @@ int dp_altmode_probe(struct typec_altmode *alt)
alt->desc = "DisplayPort";
alt->ops = &dp_altmode_ops;

+ fwnode = dev_fwnode(alt->dev.parent->parent); /* typec_port fwnode */
+ dp->connector_fwnode = fwnode_find_reference(fwnode, "displayport", 0);
+ if (IS_ERR(dp->connector_fwnode))
+ dp->connector_fwnode = NULL;
+
typec_altmode_set_drvdata(alt, dp);

dp->state = DP_STATE_ENTER;
@@ -555,6 +586,13 @@ void dp_altmode_remove(struct typec_altmode *alt)

sysfs_remove_group(&alt->dev.kobj, &dp_altmode_group);
cancel_work_sync(&dp->work);
+
+ if (dp->connector_fwnode) {
+ dp->data.conf = 0;
+ dp->data.status = 0;
+ dp_altmode_notify_connector(dp);
+ fwnode_handle_put(dp->connector_fwnode);
+ }
}
EXPORT_SYMBOL_GPL(dp_altmode_remove);

--
2.31.1