[PATCH v7 0/9] Register Type-C mode-switch in DP bridge endpoints

[PATCH v7 0/9] Register Type-C mode-switch in DP bridge endpoints

[Pin-yen Lin]

This series introduces bindings for anx7625/it6505 to register Type-C
mode-switch in their output endpoints, and use data-lanes property to
describe the pin connections.

The first two patch modifies fwnode_graph_devcon_matches and
cros_typec_init_ports to enable the registration of the switches.

Patch 4~6 introduce the bindings for anx7625 and the corresponding driver
modifications.

Patch 7~9 add similar bindings and driver changes for it6505.

v6: https://lore.kernel.org/all/20221124102056.393220-1-treapking@chromium.org/
v5: https://lore.kernel.org/linux-usb/20220622173605.1168416-1-pmalani@chromium.org/

Changes in v7:
- Fix the long comment lines
- Extracted the common codes to a helper function
- Fixed style issues in anx7625 driver
- Removed DT property validation in anx7625 driver.
- Fixed style issues in it6505 driver
- Removed the redundant sleep in it6505 driver
- Removed DT property validation in it6505 driver
- Rebased to drm-misc-next
- Fixed indentations in bindings patches
- Added a new patch to fix indentations in Kconfig

Changes in v6:
- Changed it6505_typec_mux_set callback function to accommodate with
  the latest drm-misc patches
- Changed the driver implementation to accommodate with the new binding
- Dropped typec-switch binding and use endpoints and data-lanes properties
  to describe the pin connections
- Added new patches (patch 1,2,4) to fix probing issues
- Changed the bindings of it6505/anx7625 and modified the drivers
  accordingly
- Merged it6505/anx7625 driver changes into a single patch

Pin-yen Lin (7):
  drm/display: Add Type-C switch helpers
  dt-bindings: drm/bridge: anx7625: Add mode-switch support
  drm/bridge: anx7625: Check for Type-C during panel registration
  drm/bridge: anx7625: Register Type C mode switches
  dt/bindings: drm/bridge: it6505: Add mode-switch support
  drm/bridge: it6505: Fix Kconfig indentation
  drm/bridge: it6505: Register Type C mode switches

Prashant Malani (2):
  device property: Add remote endpoint to devcon matcher
  platform/chrome: cros_ec_typec: Purge blocking switch devlinks

 .../display/bridge/analogix,anx7625.yaml      | 101 +++++++++++++-
 .../bindings/display/bridge/ite,it6505.yaml   |  95 +++++++++++--
 drivers/base/property.c                       |  15 ++
 drivers/gpu/drm/bridge/Kconfig                |  21 +--
 drivers/gpu/drm/bridge/analogix/Kconfig       |   1 +
 drivers/gpu/drm/bridge/analogix/anx7625.c     | 101 +++++++++++++-
 drivers/gpu/drm/bridge/analogix/anx7625.h     |  13 ++
 drivers/gpu/drm/bridge/ite-it6505.c           | 119 +++++++++++++++-
 drivers/gpu/drm/display/drm_dp_helper.c       | 132 ++++++++++++++++++
 drivers/platform/chrome/cros_ec_typec.c       |  10 ++
 include/drm/display/drm_dp_helper.h           |  16 +++
 11 files changed, 595 insertions(+), 29 deletions(-)

-- 
2.39.0.314.g84b9a713c41-goog

[PATCH v7 1/9] device property: Add remote endpoint to devcon matcher

[Pin-yen Lin]

From: Prashant Malani <pmalani@chromium.org>

When searching the device graph for device matches, check the
remote-endpoint itself for a match.

Some drivers register devices for individual endpoints. This allows
the matcher code to evaluate those for a match too, instead
of only looking at the remote parent devices. This is required when a
device supports two mode switches in its endpoints, so we can't simply
register the mode switch with the parent node.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
Signed-off-by: Pin-yen Lin <treapking@chromium.org>

---

(no changes since v6)

Changes in v6:
- New in v6

 drivers/base/property.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/base/property.c b/drivers/base/property.c
index 2a5a37fcd998..48877af4e444 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -1223,6 +1223,21 @@ static unsigned int fwnode_graph_devcon_matches(struct fwnode_handle *fwnode,
 			break;
 		}
 
+		/*
+		 * Some drivers may register devices for endpoints. Check
+		 * the remote-endpoints for matches in addition to the remote
+		 * port parent.
+		 */
+		node = fwnode_graph_get_remote_endpoint(ep);
+		if (fwnode_device_is_available(node)) {
+			ret = match(node, con_id, data);
+			if (ret) {
+				if (matches)
+					matches[count] = ret;
+				count++;
+			}
+		}
+
 		node = fwnode_graph_get_remote_port_parent(ep);
 		if (!fwnode_device_is_available(node)) {
 			fwnode_handle_put(node);
-- 
2.39.0.314.g84b9a713c41-goog

[PATCH v7 2/9] platform/chrome: cros_ec_typec: Purge blocking switch devlinks

[Pin-yen Lin]

From: Prashant Malani <pmalani@chromium.org>

When using OF graph, the fw_devlink code will create links between the
individual port driver (cros-ec-typec here) and the parent device for
a Type-C switch (like mode-switch). Since the mode-switch will in turn
have the usb-c-connector (i.e the child of the port driver) as a
supplier, fw_devlink will not be able to resolve the cyclic dependency
correctly.

As a result, the mode-switch driver probe() never runs, so mode-switches
are never registered. Because of that, the port driver probe constantly
fails with -EPROBE_DEFER, because the Type-C connector class requires all
switch devices to be registered prior to port registration.

To break this deadlock and allow the mode-switch registration to occur,
purge all the usb-c-connector nodes' absent suppliers. This eliminates
the connector as a supplier for a switch and allows it to be probed.

Signed-off-by: Prashant Malani <pmalani@chromium.org>

Signed-off-by: Pin-yen Lin <treapking@chromium.org>
---

Changes in v7:
- Fix the long comment lines

Changes in v6:
- New in v6

 drivers/platform/chrome/cros_ec_typec.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
index 2a7ff14dc37e..30cf03c2e95d 100644
--- a/drivers/platform/chrome/cros_ec_typec.c
+++ b/drivers/platform/chrome/cros_ec_typec.c
@@ -382,6 +382,16 @@ static int cros_typec_init_ports(struct cros_typec_data *typec)
 		return -EINVAL;
 	}
 
+	/*
+	 * OF graph may have set up some device links with switches, since
+	 * connectors have their own compatible. Purge these to avoid a deadlock
+	 * in switch probe (the switch mistakenly assumes the connector is a
+	 * supplier).
+	 */
+	if (dev->of_node)
+		device_for_each_child_node(dev, fwnode)
+			fw_devlink_purge_absent_suppliers(fwnode);
+
 	/* DT uses "reg" to specify port number. */
 	port_prop = dev->of_node ? "reg" : "port-number";
 	device_for_each_child_node(dev, fwnode) {
-- 
2.39.0.314.g84b9a713c41-goog

Re: [PATCH v7 2/9] platform/chrome: cros_ec_typec: Purge blocking switch devlinks

[Andy Shevchenko]

On Thu, Jan 05, 2023 at 09:24:50PM +0800, Pin-yen Lin wrote:
> From: Prashant Malani <pmalani@chromium.org>
> 
> When using OF graph, the fw_devlink code will create links between the
> individual port driver (cros-ec-typec here) and the parent device for
> a Type-C switch (like mode-switch). Since the mode-switch will in turn
> have the usb-c-connector (i.e the child of the port driver) as a
> supplier, fw_devlink will not be able to resolve the cyclic dependency
> correctly.
> 
> As a result, the mode-switch driver probe() never runs, so mode-switches
> are never registered. Because of that, the port driver probe constantly
> fails with -EPROBE_DEFER, because the Type-C connector class requires all
> switch devices to be registered prior to port registration.
> 
> To break this deadlock and allow the mode-switch registration to occur,
> purge all the usb-c-connector nodes' absent suppliers. This eliminates
> the connector as a supplier for a switch and allows it to be probed.

> Signed-off-by: Prashant Malani <pmalani@chromium.org>
> 
> Signed-off-by: Pin-yen Lin <treapking@chromium.org>

Tag block mustn't have the blank line(s).

...

> +	/*
> +	 * OF graph may have set up some device links with switches, since
> +	 * connectors have their own compatible. Purge these to avoid a deadlock
> +	 * in switch probe (the switch mistakenly assumes the connector is a
> +	 * supplier).
> +	 */

Perhaps even

	/*
	 * OF graph may have set up some device links with switches,
	 * since connectors have their own compatible. Purge these
	 * to avoid a deadlock in switch probe (the switch mistakenly
	 * assumes the connector is a supplier).
	 */

?

> +	if (dev->of_node)

I would use if (dev_of_node(dev)), but it's up to you and maintainers.

> +		device_for_each_child_node(dev, fwnode)
> +			fw_devlink_purge_absent_suppliers(fwnode);

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v7 2/9] platform/chrome: cros_ec_typec: Purge blocking switch devlinks

[Pin-yen Lin]

Hi Andy,

Thanks for the review.

On Thu, Jan 5, 2023 at 11:34 PM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
>
> On Thu, Jan 05, 2023 at 09:24:50PM +0800, Pin-yen Lin wrote:
> > From: Prashant Malani <pmalani@chromium.org>
> >
> > When using OF graph, the fw_devlink code will create links between the
> > individual port driver (cros-ec-typec here) and the parent device for
> > a Type-C switch (like mode-switch). Since the mode-switch will in turn
> > have the usb-c-connector (i.e the child of the port driver) as a
> > supplier, fw_devlink will not be able to resolve the cyclic dependency
> > correctly.
> >
> > As a result, the mode-switch driver probe() never runs, so mode-switches
> > are never registered. Because of that, the port driver probe constantly
> > fails with -EPROBE_DEFER, because the Type-C connector class requires all
> > switch devices to be registered prior to port registration.
> >
> > To break this deadlock and allow the mode-switch registration to occur,
> > purge all the usb-c-connector nodes' absent suppliers. This eliminates
> > the connector as a supplier for a switch and allows it to be probed.
>
> > Signed-off-by: Prashant Malani <pmalani@chromium.org>
> >
> > Signed-off-by: Pin-yen Lin <treapking@chromium.org>
>
> Tag block mustn't have the blank line(s).
>
> ...
>
> > +     /*
> > +      * OF graph may have set up some device links with switches, since
> > +      * connectors have their own compatible. Purge these to avoid a deadlock
> > +      * in switch probe (the switch mistakenly assumes the connector is a
> > +      * supplier).
> > +      */
>
> Perhaps even
>
>         /*
>          * OF graph may have set up some device links with switches,
>          * since connectors have their own compatible. Purge these
>          * to avoid a deadlock in switch probe (the switch mistakenly
>          * assumes the connector is a supplier).
>          */
>
> ?
I can update this in v8, though I wonder why shorter comments are
preferred as they haven't exceeded the 80-character length
requirement.
>
> > +     if (dev->of_node)
>
> I would use if (dev_of_node(dev)), but it's up to you and maintainers.

dev_of_node looks a bit better as it checks the enabled config for us.
I'll update this in v8.

>
> > +             device_for_each_child_node(dev, fwnode)
> > +                     fw_devlink_purge_absent_suppliers(fwnode);
>
> --
> With Best Regards,
> Andy Shevchenko
>
>

Best regards,
Pin-yen

[PATCH v7 3/9] drm/display: Add Type-C switch helpers

[Pin-yen Lin]

Add helpers to register and unregister Type-C "switches" for bridges
capable of switching their output between two downstream devices.

The helper registers USB Type-C mode switches when the "mode-switch"
and the "data-lanes" properties are available in Device Tree.

Signed-off-by: Pin-yen Lin <treapking@chromium.org>

---

Changes in v7:
- Extracted the common codes to a helper function
- New in v7

 drivers/gpu/drm/display/drm_dp_helper.c | 132 ++++++++++++++++++++++++
 include/drm/display/drm_dp_helper.h     |  16 +++
 2 files changed, 148 insertions(+)

diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c
index 16565a0a5da6..02a026f905ec 100644
--- a/drivers/gpu/drm/display/drm_dp_helper.c
+++ b/drivers/gpu/drm/display/drm_dp_helper.c
@@ -30,11 +30,13 @@
 #include <linux/sched.h>
 #include <linux/seq_file.h>
 #include <linux/string_helpers.h>
+#include <linux/usb/typec_mux.h>
 #include <linux/dynamic_debug.h>
 
 #include <drm/display/drm_dp_helper.h>
 #include <drm/display/drm_dp_mst_helper.h>
 #include <drm/drm_edid.h>
+#include <drm/drm_of.h>
 #include <drm/drm_print.h>
 #include <drm/drm_vblank.h>
 #include <drm/drm_panel.h>
@@ -3891,3 +3893,133 @@ int drm_panel_dp_aux_backlight(struct drm_panel *panel, struct drm_dp_aux *aux)
 EXPORT_SYMBOL(drm_panel_dp_aux_backlight);
 
 #endif
+
+#if IS_ENABLED(CONFIG_TYPEC)
+static int drm_dp_register_mode_switch(struct device *dev, struct device_node *node,
+				       struct drm_dp_typec_switch_desc *switch_desc,
+				       void *data, void *mux_set)
+{
+	struct drm_dp_typec_port_data *port_data;
+	struct typec_mux_desc mux_desc = {};
+	char name[32];
+	u32 dp_lanes[2];
+	int ret, num_lanes, port_num = -1;
+
+	num_lanes = drm_of_get_data_lanes_count(node, 0, 2);
+	if (num_lanes <= 0) {
+		dev_err(dev, "Error on getting data lanes count: %d\n",
+			num_lanes);
+		return num_lanes;
+	}
+
+	ret = of_property_read_u32_array(node, "data-lanes", dp_lanes, num_lanes);
+	if (ret) {
+		dev_err(dev, "Failed to read the data-lanes variable: %d\n",
+			ret);
+		return ret;
+	}
+
+	port_num = dp_lanes[0] / 2;
+
+	port_data = &switch_desc->typec_ports[port_num];
+	port_data->data = data;
+	mux_desc.fwnode = &node->fwnode;
+	mux_desc.drvdata = port_data;
+	snprintf(name, sizeof(name), "%s-%u", node->name, port_num);
+	mux_desc.name = name;
+	mux_desc.set = mux_set;
+
+	port_data->typec_mux = typec_mux_register(dev, &mux_desc);
+	if (IS_ERR(port_data->typec_mux)) {
+		ret = PTR_ERR(port_data->typec_mux);
+		dev_err(dev, "Mode switch register for port %d failed: %d\n",
+			port_num, ret);
+	}
+
+	return ret;
+}
+
+/**
+ * drm_dp_register_typec_switches() - register Type-C switches
+ * @dev: Device that registers Type-C switches
+ * @port: Device node for the switch
+ * @switch_desc: A Type-C switch descriptor
+ * @data: Private data for the switches
+ * @mux_set: Callback function for typec_mux_set
+ *
+ * This function registers USB Type-C switches for DP bridges that can switch
+ * the output signal between their output pins.
+ *
+ * Currently only mode switches are implemented, and the function assumes the
+ * given @port device node has endpoints with "mode-switch" property.
+ * Register the endpoint as port 0 if the "data-lanes" property falls in 0/1,
+ * and register it as port 1 if "data-lanes" falls in 2/3.
+ */
+int drm_dp_register_typec_switches(struct device *dev, struct device_node *port,
+				   struct drm_dp_typec_switch_desc *switch_desc,
+				   void *data, void *mux_set)
+{
+	struct device_node *sw;
+	int ret = 0;
+
+	for_each_child_of_node(port, sw) {
+		if (of_property_read_bool(sw, "mode-switch"))
+			switch_desc->num_typec_switches++;
+	}
+
+	if (!switch_desc->num_typec_switches) {
+		dev_warn(dev, "No Type-C switches node found\n");
+		return ret;
+	}
+
+	switch_desc->typec_ports = devm_kcalloc(
+		dev, switch_desc->num_typec_switches,
+		sizeof(struct drm_dp_typec_port_data), GFP_KERNEL);
+
+	if (!switch_desc->typec_ports)
+		return -ENOMEM;
+
+	/* Register switches for each connector. */
+	for_each_child_of_node(port, sw) {
+		if (!of_property_read_bool(sw, "mode-switch"))
+			continue;
+		ret = drm_dp_register_mode_switch(dev, sw, switch_desc, data, mux_set);
+		if (ret) {
+			dev_err(dev, "Failed to register mode switch: %d\n", ret);
+			of_node_put(sw);
+			break;
+		}
+	}
+
+	if (ret)
+		drm_dp_unregister_typec_switches(switch_desc);
+
+	return ret;
+}
+EXPORT_SYMBOL(drm_dp_register_typec_switches);
+
+/**
+ * drm_dp_unregister_typec_switches() - unregister Type-C switches
+ * @switch_desc: A Type-C switch descriptor
+ */
+void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc)
+{
+	int i;
+
+	for (i = 0; i < switch_desc->num_typec_switches; i++)
+		typec_mux_unregister(switch_desc->typec_ports[i].typec_mux);
+}
+EXPORT_SYMBOL(drm_dp_unregister_typec_switches);
+#else
+void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc)
+{
+}
+EXPORT_SYMBOL(drm_dp_register_typec_switches);
+int drm_dp_register_typec_switches(struct device *dev, struct device_node *port,
+				   struct drm_dp_typec_switch_desc *switch_desc,
+				   void *data, void *mux_set)
+{
+	return 0;
+}
+EXPORT_SYMBOL(drm_dp_unregister_typec_switches);
+#endif
diff --git a/include/drm/display/drm_dp_helper.h b/include/drm/display/drm_dp_helper.h
index ab55453f2d2c..fef0a9a0d8ea 100644
--- a/include/drm/display/drm_dp_helper.h
+++ b/include/drm/display/drm_dp_helper.h
@@ -763,4 +763,20 @@ bool drm_dp_downstream_rgb_to_ycbcr_conversion(const u8 dpcd[DP_RECEIVER_CAP_SIZ
 					       const u8 port_cap[4], u8 color_spc);
 int drm_dp_pcon_convert_rgb_to_ycbcr(struct drm_dp_aux *aux, u8 color_spc);
 
+struct drm_dp_typec_port_data {
+	struct typec_mux_dev *typec_mux;
+	void *data;
+	bool dp_connected;
+};
+
+struct drm_dp_typec_switch_desc {
+	int num_typec_switches;
+	struct drm_dp_typec_port_data *typec_ports;
+};
+
+void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc);
+int drm_dp_register_typec_switches(struct device *dev, struct device_node *port,
+				   struct drm_dp_typec_switch_desc *switch_desc,
+				   void *data, void *mux_set);
+
 #endif /* _DRM_DP_HELPER_H_ */
-- 
2.39.0.314.g84b9a713c41-goog

Re: [PATCH v7 3/9] drm/display: Add Type-C switch helpers

[Andy Shevchenko]

On Thu, Jan 05, 2023 at 09:24:51PM +0800, Pin-yen Lin wrote:
> Add helpers to register and unregister Type-C "switches" for bridges
> capable of switching their output between two downstream devices.
> 
> The helper registers USB Type-C mode switches when the "mode-switch"
> and the "data-lanes" properties are available in Device Tree.

...

> +	port_data->typec_mux = typec_mux_register(dev, &mux_desc);
> +	if (IS_ERR(port_data->typec_mux)) {
> +		ret = PTR_ERR(port_data->typec_mux);
> +		dev_err(dev, "Mode switch register for port %d failed: %d\n",
> +			port_num, ret);
> +	}
> +
> +	return ret;

...

> +	struct device_node *sw;

> +	int ret = 0;

It's easy to break things if you squeeze more code in the future in this
function, so I recommend to split assignment to be closer to its first user
(see below).

> +	for_each_child_of_node(port, sw) {
> +		if (of_property_read_bool(sw, "mode-switch"))
> +			switch_desc->num_typec_switches++;
> +	}
> +
> +	if (!switch_desc->num_typec_switches) {
> +		dev_warn(dev, "No Type-C switches node found\n");

> +		return ret;

return 0;

> +	}
> +
> +	switch_desc->typec_ports = devm_kcalloc(
> +		dev, switch_desc->num_typec_switches,
> +		sizeof(struct drm_dp_typec_port_data), GFP_KERNEL);
> +
> +	if (!switch_desc->typec_ports)
> +		return -ENOMEM;

> +	/* Register switches for each connector. */
> +	for_each_child_of_node(port, sw) {
> +		if (!of_property_read_bool(sw, "mode-switch"))
> +			continue;
> +		ret = drm_dp_register_mode_switch(dev, sw, switch_desc, data, mux_set);
> +		if (ret) {
> +			dev_err(dev, "Failed to register mode switch: %d\n", ret);
> +			of_node_put(sw);
> +			break;
> +		}
> +	}

> +	if (ret)
> +		drm_dp_unregister_typec_switches(switch_desc);
> +
> +	return ret;

Why not adding a goto label?

		ret = drm_dp_register_mode_switch(dev, sw, switch_desc, data, mux_set);
		if (ret)
			goto err_unregister_typec_switches;

	return 0;

err_unregister_typec_switches:
	of_node_put(sw);
	drm_dp_unregister_typec_switches(switch_desc);
	dev_err(dev, "Failed to register mode switch: %d\n", ret);
	return ret;

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v7 3/9] drm/display: Add Type-C switch helpers

[Pin-yen Lin]

Hi Andy,

Thanks for the review.

On Thu, Jan 5, 2023 at 11:41 PM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
>
> On Thu, Jan 05, 2023 at 09:24:51PM +0800, Pin-yen Lin wrote:
> > Add helpers to register and unregister Type-C "switches" for bridges
> > capable of switching their output between two downstream devices.
> >
> > The helper registers USB Type-C mode switches when the "mode-switch"
> > and the "data-lanes" properties are available in Device Tree.
>
> ...
>
> > +     port_data->typec_mux = typec_mux_register(dev, &mux_desc);
> > +     if (IS_ERR(port_data->typec_mux)) {
> > +             ret = PTR_ERR(port_data->typec_mux);
> > +             dev_err(dev, "Mode switch register for port %d failed: %d\n",
> > +                     port_num, ret);
> > +     }
> > +
> > +     return ret;
>
> ...
>
> > +     struct device_node *sw;
>
> > +     int ret = 0;
>
> It's easy to break things if you squeeze more code in the future in this
> function, so I recommend to split assignment to be closer to its first user
> (see below).
>
> > +     for_each_child_of_node(port, sw) {
> > +             if (of_property_read_bool(sw, "mode-switch"))
> > +                     switch_desc->num_typec_switches++;
> > +     }
> > +
> > +     if (!switch_desc->num_typec_switches) {
> > +             dev_warn(dev, "No Type-C switches node found\n");
>
> > +             return ret;
>
> return 0;

Thanks for the suggestion. I'll update this in v8.
>
> > +     }
> > +
> > +     switch_desc->typec_ports = devm_kcalloc(
> > +             dev, switch_desc->num_typec_switches,
> > +             sizeof(struct drm_dp_typec_port_data), GFP_KERNEL);
> > +
> > +     if (!switch_desc->typec_ports)
> > +             return -ENOMEM;
>
> > +     /* Register switches for each connector. */
> > +     for_each_child_of_node(port, sw) {
> > +             if (!of_property_read_bool(sw, "mode-switch"))
> > +                     continue;
> > +             ret = drm_dp_register_mode_switch(dev, sw, switch_desc, data, mux_set);
> > +             if (ret) {
> > +                     dev_err(dev, "Failed to register mode switch: %d\n", ret);
> > +                     of_node_put(sw);
> > +                     break;
> > +             }
> > +     }
>
> > +     if (ret)
> > +             drm_dp_unregister_typec_switches(switch_desc);
> > +
> > +     return ret;
>
> Why not adding a goto label?

I didn't know that goto label is preferred even when there are no
duplicated code blocks in the function.

I'll update this accordingly in v8.
>
>                 ret = drm_dp_register_mode_switch(dev, sw, switch_desc, data, mux_set);
>                 if (ret)
>                         goto err_unregister_typec_switches;
>
>         return 0;
>
> err_unregister_typec_switches:
>         of_node_put(sw);
>         drm_dp_unregister_typec_switches(switch_desc);
>         dev_err(dev, "Failed to register mode switch: %d\n", ret);
>         return ret;
>
> --
> With Best Regards,
> Andy Shevchenko
>
>
Best regards,
Pin-yen

[PATCH v7 4/9] dt-bindings: drm/bridge: anx7625: Add mode-switch support

[Pin-yen Lin]

Analogix 7625 can be used in systems to switch the DP traffic between
two downstreams, which can be USB Type-C DisplayPort alternate mode
lane or regular DisplayPort output ports.

Update the binding to accommodate this usage by introducing a
data-lanes and a mode-switch property on endpoints.

Also include the link to the product brief in the bindings.

Signed-off-by: Pin-yen Lin <treapking@chromium.org>

---

Changes in v7:
- Fixed issues reported by dt_binding_check
- Updated the schema and the example dts for data-lanes.
- Changed to generic naming for the example dts node.

Changes in v6:
- Remove switches node and use endpoints and data-lanes property to
  describe the connections.

 .../display/bridge/analogix,anx7625.yaml      | 101 +++++++++++++++++-
 1 file changed, 98 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/bridge/analogix,anx7625.yaml b/Documentation/devicetree/bindings/display/bridge/analogix,anx7625.yaml
index 4590186c4a0b..536dbe8eaf60 100644
--- a/Documentation/devicetree/bindings/display/bridge/analogix,anx7625.yaml
+++ b/Documentation/devicetree/bindings/display/bridge/analogix,anx7625.yaml
@@ -12,7 +12,8 @@ maintainers:
 
 description: |
   The ANX7625 is an ultra-low power 4K Mobile HD Transmitter
-  designed for portable devices.
+  designed for portable devices. Product brief is available at
+  https://www.analogix.com/en/system/files/AA-002291-PB-6-ANX7625_ProductBrief.pdf
 
 properties:
   compatible:
@@ -112,10 +113,50 @@ properties:
               data-lanes: true
 
       port@1:
-        $ref: /schemas/graph.yaml#/properties/port
+        $ref: /schemas/graph.yaml#/$defs/port-base
         description:
           Video port for panel or connector.
 
+        patternProperties:
+          "^endpoint@[01]$":
+            $ref: /schemas/graph.yaml#/$defs/endpoint-base
+            unevaluatedProperties: false
+
+            properties:
+              reg:
+                maxItems: 1
+
+              remote-endpoint: true
+
+              data-lanes:
+                oneOf:
+                  - minItems: 1
+                    maxItems: 1
+                    items:
+                      enum: [0, 1, 2, 3]
+
+                  - items:
+                      - const: 0
+                      - const: 1
+
+                  - items:
+                      - const: 2
+                      - const: 3
+
+                  - items:
+                      - const: 0
+                      - const: 1
+                      - const: 2
+                      - const: 3
+
+              mode-switch:
+                type: boolean
+                description: Register this node as a Type-C mode switch or not.
+
+            required:
+              - reg
+              - remote-endpoint
+
     required:
       - port@0
       - port@1
@@ -164,8 +205,12 @@ examples:
                 };
 
                 mipi2dp_bridge_out: port@1 {
+                    #address-cells = <1>;
+                    #size-cells = <0>;
+
                     reg = <1>;
-                    anx7625_out: endpoint {
+                    anx7625_out: endpoint@0 {
+                        reg = <0>;
                         remote-endpoint = <&panel_in>;
                     };
                 };
@@ -186,3 +231,53 @@ examples:
             };
         };
     };
+  - |
+    i2c3 {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        encoder@58 {
+            compatible = "analogix,anx7625";
+            reg = <0x58>;
+            pinctrl-names = "default";
+            pinctrl-0 = <&anx7625_dp_pins>;
+            enable-gpios = <&pio 176 GPIO_ACTIVE_HIGH>;
+            reset-gpios = <&pio 177 GPIO_ACTIVE_HIGH>;
+            vdd10-supply = <&pp1100_dpbrdg>;
+            vdd18-supply = <&pp1800_dpbrdg_dx>;
+            vdd33-supply = <&pp3300_dpbrdg_dx>;
+            analogix,audio-enable;
+
+            ports {
+                #address-cells = <1>;
+                #size-cells = <0>;
+
+                port@0 {
+                    reg = <0>;
+                    anx7625_dp_in: endpoint {
+                        bus-type = <7>;
+                        remote-endpoint = <&dpi_out>;
+                    };
+                };
+
+                port@1 {
+                    #address-cells = <1>;
+                    #size-cells = <0>;
+
+                    reg = <1>;
+                    anx_typec0: endpoint@0 {
+                        reg = <0>;
+                        mode-switch;
+                        data-lanes = <0 1>;
+                        remote-endpoint = <&typec_port0>;
+                    };
+                    anx_typec1: endpoint@1 {
+                        reg = <1>;
+                        mode-switch;
+                        data-lanes = <2 3>;
+                        remote-endpoint = <&typec_port1>;
+                    };
+                };
+            };
+        };
+    };
-- 
2.39.0.314.g84b9a713c41-goog

[PATCH v7 5/9] drm/bridge: anx7625: Check for Type-C during panel registration

[Pin-yen Lin]

The output port endpoints can be connected to USB-C connectors.
Running drm_of_find_panel_or_bridge() with such endpoints leads to
a continuous return value of -EPROBE_DEFER, even though there is
no panel present.

To avoid this, check for the existence of a "mode-switch" property in
the port endpoint, and skip panel registration completely if so.

Signed-off-by: Pin-yen Lin <treapking@chromium.org>

---

(no changes since v6)

Changes in v6:
- New in v6

 drivers/gpu/drm/bridge/analogix/anx7625.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index b375887e655d..1cf242130b91 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -1649,7 +1649,7 @@ static int anx7625_get_swing_setting(struct device *dev,
 static int anx7625_parse_dt(struct device *dev,
 			    struct anx7625_platform_data *pdata)
 {
-	struct device_node *np = dev->of_node, *ep0;
+	struct device_node *np = dev->of_node, *ep0, *sw;
 	int bus_type, mipi_lanes;
 
 	anx7625_get_swing_setting(dev, pdata);
@@ -1688,6 +1688,17 @@ static int anx7625_parse_dt(struct device *dev,
 	if (of_property_read_bool(np, "analogix,audio-enable"))
 		pdata->audio_en = 1;
 
+	/*
+	 * Don't bother finding a panel if a Type-C `mode-switch` property is
+	 * present in one of the endpoints.
+	 */
+	for_each_endpoint_of_node(np, sw) {
+		if (of_property_read_bool(sw, "mode-switch")) {
+			of_node_put(sw);
+			return 0;
+		}
+	}
+
 	pdata->panel_bridge = devm_drm_of_get_bridge(dev, np, 1, 0);
 	if (IS_ERR(pdata->panel_bridge)) {
 		if (PTR_ERR(pdata->panel_bridge) == -ENODEV) {
-- 
2.39.0.314.g84b9a713c41-goog

[PATCH v7 6/9] drm/bridge: anx7625: Register Type C mode switches

[Pin-yen Lin]

Register USB Type-C mode switches when the "mode-switch" property and
relevant port are available in Device Tree. Configure the crosspoint
switch based on the entered alternate mode for a specific Type-C
connector.

Signed-off-by: Pin-yen Lin <treapking@chromium.org>

---

Changes in v7:
- Fixed style issues in anx7625 driver
- Removed DT property validation in anx7625 driver.
- Extracted common codes to another commit.

Changes in v6:
- Squashed to a single patch

 drivers/gpu/drm/bridge/analogix/Kconfig   |  1 +
 drivers/gpu/drm/bridge/analogix/anx7625.c | 88 +++++++++++++++++++++++
 drivers/gpu/drm/bridge/analogix/anx7625.h | 13 ++++
 3 files changed, 102 insertions(+)

diff --git a/drivers/gpu/drm/bridge/analogix/Kconfig b/drivers/gpu/drm/bridge/analogix/Kconfig
index 173dada218ec..992b43ed1dd7 100644
--- a/drivers/gpu/drm/bridge/analogix/Kconfig
+++ b/drivers/gpu/drm/bridge/analogix/Kconfig
@@ -34,6 +34,7 @@ config DRM_ANALOGIX_ANX7625
 	tristate "Analogix Anx7625 MIPI to DP interface support"
 	depends on DRM
 	depends on OF
+	depends on TYPEC || TYPEC=n
 	select DRM_DISPLAY_DP_HELPER
 	select DRM_DISPLAY_HDCP_HELPER
 	select DRM_DISPLAY_HELPER
diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index 1cf242130b91..2bb504a8d789 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -15,6 +15,8 @@
 #include <linux/regulator/consumer.h>
 #include <linux/slab.h>
 #include <linux/types.h>
+#include <linux/usb/typec_dp.h>
+#include <linux/usb/typec_mux.h>
 #include <linux/workqueue.h>
 
 #include <linux/of_gpio.h>
@@ -2572,6 +2574,86 @@ static void anx7625_runtime_disable(void *data)
 	pm_runtime_disable(data);
 }
 
+static void anx7625_set_crosspoint_switch(struct anx7625_data *ctx,
+					  enum typec_orientation orientation)
+{
+	if (orientation == TYPEC_ORIENTATION_NORMAL) {
+		anx7625_reg_write(ctx, ctx->i2c.tcpc_client, TCPC_SWITCH_0,
+				  SW_SEL1_SSRX_RX1 | SW_SEL1_DPTX0_RX2);
+		anx7625_reg_write(ctx, ctx->i2c.tcpc_client, TCPC_SWITCH_1,
+				  SW_SEL2_SSTX_TX1 | SW_SEL2_DPTX1_TX2);
+	} else if (orientation == TYPEC_ORIENTATION_REVERSE) {
+		anx7625_reg_write(ctx, ctx->i2c.tcpc_client, TCPC_SWITCH_0,
+				  SW_SEL1_SSRX_RX2 | SW_SEL1_DPTX0_RX1);
+		anx7625_reg_write(ctx, ctx->i2c.tcpc_client, TCPC_SWITCH_1,
+				  SW_SEL2_SSTX_TX2 | SW_SEL2_DPTX1_TX1);
+	}
+}
+
+static void anx7625_typec_two_ports_update(struct anx7625_data *ctx)
+{
+	struct drm_dp_typec_switch_desc switch_desc = ctx->switch_desc;
+	/* Check if both ports available and do nothing to retain the current one */
+	if (switch_desc.typec_ports[0].dp_connected && switch_desc.typec_ports[1].dp_connected)
+		return;
+
+	if (switch_desc.typec_ports[0].dp_connected)
+		anx7625_set_crosspoint_switch(ctx, TYPEC_ORIENTATION_NORMAL);
+	else if (switch_desc.typec_ports[1].dp_connected)
+		anx7625_set_crosspoint_switch(ctx, TYPEC_ORIENTATION_REVERSE);
+}
+
+static int anx7625_typec_mux_set(struct typec_mux_dev *mux,
+				 struct typec_mux_state *state)
+{
+	struct drm_dp_typec_port_data *port_data = typec_mux_get_drvdata(mux);
+	struct anx7625_data *ctx = (struct anx7625_data *) port_data->data;
+	struct device *dev = &ctx->client->dev;
+	struct drm_dp_typec_switch_desc switch_desc = ctx->switch_desc;
+	bool new_dp_connected, old_dp_connected;
+
+	if (switch_desc.num_typec_switches == 1)
+		return 0;
+
+	old_dp_connected = switch_desc.typec_ports[0].dp_connected ||
+			   switch_desc.typec_ports[1].dp_connected;
+
+	port_data->dp_connected = state->alt &&
+				  state->alt->svid == USB_TYPEC_DP_SID &&
+				  state->alt->mode == USB_TYPEC_DP_MODE;
+
+	dev_dbg(dev, "mux_set dp_connected: c0=%d, c1=%d\n",
+		switch_desc.typec_ports[0].dp_connected, switch_desc.typec_ports[1].dp_connected);
+
+	new_dp_connected = switch_desc.typec_ports[0].dp_connected ||
+			   switch_desc.typec_ports[1].dp_connected;
+
+	/* dp on, power on first */
+	if (!old_dp_connected && new_dp_connected)
+		pm_runtime_get_sync(dev);
+
+	anx7625_typec_two_ports_update(ctx);
+
+	/* dp off, power off last */
+	if (old_dp_connected && !new_dp_connected)
+		pm_runtime_put_sync(dev);
+
+	return 0;
+}
+
+static void anx7625_unregister_typec_switches(struct anx7625_data *ctx)
+{
+	drm_dp_unregister_typec_switches(&ctx->switch_desc);
+}
+
+static int anx7625_register_typec_switches(struct device *dev, struct anx7625_data *ctx)
+{
+	struct device_node *port = of_graph_get_port_by_id(dev->of_node, 1);
+
+	return drm_dp_register_typec_switches(dev, port, &ctx->switch_desc,
+					      ctx, anx7625_typec_mux_set);
+}
+
 static int anx7625_i2c_probe(struct i2c_client *client)
 {
 	struct anx7625_data *platform;
@@ -2679,6 +2761,10 @@ static int anx7625_i2c_probe(struct i2c_client *client)
 	if (platform->pdata.intp_irq)
 		queue_work(platform->workqueue, &platform->work);
 
+	ret = anx7625_register_typec_switches(dev, platform);
+	if (ret && ret != -ENODEV)
+		dev_warn(dev, "Didn't register Type-C switches, err: %d\n", ret);
+
 	platform->bridge.funcs = &anx7625_bridge_funcs;
 	platform->bridge.of_node = client->dev.of_node;
 	if (!anx7625_of_panel_on_aux_bus(&client->dev))
@@ -2730,6 +2816,8 @@ static void anx7625_i2c_remove(struct i2c_client *client)
 
 	drm_bridge_remove(&platform->bridge);
 
+	anx7625_unregister_typec_switches(platform);
+
 	if (platform->pdata.intp_irq)
 		destroy_workqueue(platform->workqueue);
 
diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.h b/drivers/gpu/drm/bridge/analogix/anx7625.h
index 14f33d6be289..38abbd3d6b36 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.h
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.h
@@ -55,6 +55,18 @@
 #define HPD_STATUS_CHANGE 0x80
 #define HPD_STATUS 0x80
 
+#define TCPC_SWITCH_0 0xB4
+#define SW_SEL1_DPTX0_RX2 BIT(0)
+#define SW_SEL1_DPTX0_RX1 BIT(1)
+#define SW_SEL1_SSRX_RX2 BIT(4)
+#define SW_SEL1_SSRX_RX1 BIT(5)
+
+#define TCPC_SWITCH_1 0xB5
+#define SW_SEL2_DPTX1_TX2 BIT(0)
+#define SW_SEL2_DPTX1_TX1 BIT(1)
+#define SW_SEL2_SSTX_TX2 BIT(4)
+#define SW_SEL2_SSTX_TX1 BIT(5)
+
 /******** END of I2C Address 0x58 ********/
 
 /***************************************************************/
@@ -479,6 +491,7 @@ struct anx7625_data {
 	struct drm_connector *connector;
 	struct mipi_dsi_device *dsi;
 	struct drm_dp_aux aux;
+	struct drm_dp_typec_switch_desc switch_desc;
 };
 
 #endif  /* __ANX7625_H__ */
-- 
2.39.0.314.g84b9a713c41-goog

[PATCH v7 7/9] dt/bindings: drm/bridge: it6505: Add mode-switch support

[Pin-yen Lin]

ITE IT6505 can be used in systems to switch the DP traffic between
two downstreams, which can be USB Type-C DisplayPort alternate mode
lane or regular DisplayPort output ports.

Update the binding to accommodate this usage by introducing a
data-lanes and a mode-switch property on endpoints.

Signed-off-by: Pin-yen Lin <treapking@chromium.org>

---

Changes in v7:
- Fixed issues reported by dt_binding_check.
- Updated the schema and the example dts for data-lanes.
- Changed to generic naming for the example dts node.

Changes in v6:
- Remove switches node and use endpoints and data-lanes property to
  describe the connections.

 .../bindings/display/bridge/ite,it6505.yaml   | 95 ++++++++++++++++---
 1 file changed, 84 insertions(+), 11 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml b/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
index b16a9d9127dd..1ee7cd0d2035 100644
--- a/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
+++ b/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
@@ -77,20 +77,45 @@ properties:
         unevaluatedProperties: false
         description: Video port for DP output
 
-        properties:
-          endpoint:
+        patternProperties:
+          "^endpoint@[01]$":
             $ref: /schemas/graph.yaml#/$defs/endpoint-base
             unevaluatedProperties: false
 
             properties:
+              reg:
+                maxItems: 1
+
+              remote-endpoint: true
+
               data-lanes:
-                minItems: 1
-                uniqueItems: true
-                items:
-                  - enum: [ 0, 1 ]
-                  - const: 1
-                  - const: 2
-                  - const: 3
+                oneOf:
+                  - minItems: 1
+                    maxItems: 1
+                    items:
+                      enum: [0, 1, 2, 3]
+
+                  - items:
+                      - const: 0
+                      - const: 1
+
+                  - items:
+                      - const: 2
+                      - const: 3
+
+                  - items:
+                      - const: 0
+                      - const: 1
+                      - const: 2
+                      - const: 3
+
+              mode-switch:
+                type: boolean
+                description: Register this node as a Type-C mode switch or not.
+
+            required:
+              - reg
+              - remote-endpoint
 
     required:
       - port@0
@@ -102,7 +127,6 @@ required:
   - pwr18-supply
   - interrupts
   - reset-gpios
-  - extcon
   - ports
 
 additionalProperties: false
@@ -139,8 +163,11 @@ examples:
                 };
 
                 port@1 {
+                    #address-cells = <1>;
+                    #size-cells = <0>;
                     reg = <1>;
-                    it6505_out: endpoint {
+                    it6505_out: endpoint@0 {
+                        reg = <0>;
                         remote-endpoint = <&dp_in>;
                         data-lanes = <0 1>;
                     };
@@ -148,3 +175,49 @@ examples:
             };
         };
     };
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    i2c3 {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        dp-bridge@5c {
+            compatible = "ite,it6505";
+            interrupts = <8 IRQ_TYPE_LEVEL_LOW 8 0>;
+            reg = <0x5c>;
+            pinctrl-names = "default";
+            pinctrl-0 = <&it6505_pins>;
+            ovdd-supply = <&mt6366_vsim2_reg>;
+            pwr18-supply = <&pp1800_dpbrdg_dx>;
+            reset-gpios = <&pio 177 0>;
+
+            ports {
+                #address-cells = <1>;
+                #size-cells = <0>;
+                port@0 {
+                    reg = <0>;
+                    it6505_dpi_in: endpoint {
+                        remote-endpoint = <&dpi_out>;
+                    };
+                };
+                port@1 {
+                    #address-cells = <1>;
+                    #size-cells = <0>;
+                    reg = <1>;
+                    ite_typec0: endpoint@0 {
+                        reg = <0>;
+                        mode-switch;
+                        data-lanes = <0 1>;
+                        remote-endpoint = <&typec_port0>;
+                    };
+                    ite_typec1: endpoint@1 {
+                        reg = <1>;
+                        mode-switch;
+                        data-lanes = <2 3>;
+                        remote-endpoint = <&typec_port1>;
+                    };
+                };
+            };
+        };
+    };
-- 
2.39.0.314.g84b9a713c41-goog

Re: [PATCH v7 7/9] dt/bindings: drm/bridge: it6505: Add mode-switch support

[Krzysztof Kozlowski]

On 05/01/2023 14:24, Pin-yen Lin wrote:
> ITE IT6505 can be used in systems to switch the DP traffic between
> two downstreams, which can be USB Type-C DisplayPort alternate mode
> lane or regular DisplayPort output ports.

Use subject prefixes matching the subsystem (which you can get for
example with `git log --oneline -- DIRECTORY_OR_FILE` on the directory
your patch is touching).

> 
> Update the binding to accommodate this usage by introducing a
> data-lanes and a mode-switch property on endpoints.
> 
> Signed-off-by: Pin-yen Lin <treapking@chromium.org>
> 
> ---
> 
> Changes in v7:
> - Fixed issues reported by dt_binding_check.
> - Updated the schema and the example dts for data-lanes.
> - Changed to generic naming for the example dts node.
> 
> Changes in v6:
> - Remove switches node and use endpoints and data-lanes property to
>   describe the connections.
> 
>  .../bindings/display/bridge/ite,it6505.yaml   | 95 ++++++++++++++++---
>  1 file changed, 84 insertions(+), 11 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml b/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
> index b16a9d9127dd..1ee7cd0d2035 100644
> --- a/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
> +++ b/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
> @@ -77,20 +77,45 @@ properties:
>          unevaluatedProperties: false
>          description: Video port for DP output
>  
> -        properties:
> -          endpoint:
> +        patternProperties:
> +          "^endpoint@[01]$":
>              $ref: /schemas/graph.yaml#/$defs/endpoint-base
>              unevaluatedProperties: false
>  
>              properties:
> +              reg:
> +                maxItems: 1
> +
> +              remote-endpoint: true
> +
>                data-lanes:
> -                minItems: 1
> -                uniqueItems: true
> -                items:
> -                  - enum: [ 0, 1 ]
> -                  - const: 1
> -                  - const: 2
> -                  - const: 3
> +                oneOf:
> +                  - minItems: 1

Drop minItems.

> +                    maxItems: 1

Actually drop this as well and just use items with one item (enum).

> +                    items:
> +                      enum: [0, 1, 2, 3]
> +
> +                  - items:
> +                      - const: 0
> +                      - const: 1
> +
> +                  - items:
> +                      - const: 2
> +                      - const: 3
> +
> +                  - items:
> +                      - const: 0
> +                      - const: 1
> +                      - const: 2
> +                      - const: 3
> +
> +              mode-switch:
> +                type: boolean
> +                description: Register this node as a Type-C mode switch or not.
> +
> +            required:
> +              - reg
> +              - remote-endpoint
>  
>      required:
>        - port@0
> @@ -102,7 +127,6 @@ required:
>    - pwr18-supply
>    - interrupts
>    - reset-gpios
> -  - extcon
>    - ports
>  
>  additionalProperties: false
> @@ -139,8 +163,11 @@ examples:
>                  };
>  
>                  port@1 {
> +                    #address-cells = <1>;
> +                    #size-cells = <0>;
>                      reg = <1>;
> -                    it6505_out: endpoint {
> +                    it6505_out: endpoint@0 {
> +                        reg = <0>;
>                          remote-endpoint = <&dp_in>;
>                          data-lanes = <0 1>;
>                      };
> @@ -148,3 +175,49 @@ examples:
>              };
>          };
>      };
> +  - |
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +
> +    i2c3 {

Just i2c

Best regards,
Krzysztof

Re: [PATCH v7 7/9] dt/bindings: drm/bridge: it6505: Add mode-switch support

[Pin-yen Lin]

Hi Krzysztof,

Thanks for the review.

On Fri, Jan 6, 2023 at 8:48 PM Krzysztof Kozlowski
<krzysztof.kozlowski@linaro.org> wrote:
>
> On 05/01/2023 14:24, Pin-yen Lin wrote:
> > ITE IT6505 can be used in systems to switch the DP traffic between
> > two downstreams, which can be USB Type-C DisplayPort alternate mode
> > lane or regular DisplayPort output ports.
>
> Use subject prefixes matching the subsystem (which you can get for
> example with `git log --oneline -- DIRECTORY_OR_FILE` on the directory
> your patch is touching).

I'll fix this in this patch and the one for anx7625.
>
> >
> > Update the binding to accommodate this usage by introducing a
> > data-lanes and a mode-switch property on endpoints.
> >
> > Signed-off-by: Pin-yen Lin <treapking@chromium.org>
> >
> > ---
> >
> > Changes in v7:
> > - Fixed issues reported by dt_binding_check.
> > - Updated the schema and the example dts for data-lanes.
> > - Changed to generic naming for the example dts node.
> >
> > Changes in v6:
> > - Remove switches node and use endpoints and data-lanes property to
> >   describe the connections.
> >
> >  .../bindings/display/bridge/ite,it6505.yaml   | 95 ++++++++++++++++---
> >  1 file changed, 84 insertions(+), 11 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml b/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
> > index b16a9d9127dd..1ee7cd0d2035 100644
> > --- a/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
> > +++ b/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
> > @@ -77,20 +77,45 @@ properties:
> >          unevaluatedProperties: false
> >          description: Video port for DP output
> >
> > -        properties:
> > -          endpoint:
> > +        patternProperties:
> > +          "^endpoint@[01]$":
> >              $ref: /schemas/graph.yaml#/$defs/endpoint-base
> >              unevaluatedProperties: false
> >
> >              properties:
> > +              reg:
> > +                maxItems: 1
> > +
> > +              remote-endpoint: true
> > +
> >                data-lanes:
> > -                minItems: 1
> > -                uniqueItems: true
> > -                items:
> > -                  - enum: [ 0, 1 ]
> > -                  - const: 1
> > -                  - const: 2
> > -                  - const: 3
> > +                oneOf:
> > +                  - minItems: 1
>
> Drop minItems.
>
> > +                    maxItems: 1
>
> Actually drop this as well and just use items with one item (enum).

Sure I'll update this in v8.
>
> > +                    items:
> > +                      enum: [0, 1, 2, 3]
> > +
> > +                  - items:
> > +                      - const: 0
> > +                      - const: 1
> > +
> > +                  - items:
> > +                      - const: 2
> > +                      - const: 3
> > +
> > +                  - items:
> > +                      - const: 0
> > +                      - const: 1
> > +                      - const: 2
> > +                      - const: 3
> > +
> > +              mode-switch:
> > +                type: boolean
> > +                description: Register this node as a Type-C mode switch or not.
> > +
> > +            required:
> > +              - reg
> > +              - remote-endpoint
> >
> >      required:
> >        - port@0
> > @@ -102,7 +127,6 @@ required:
> >    - pwr18-supply
> >    - interrupts
> >    - reset-gpios
> > -  - extcon
> >    - ports
> >
> >  additionalProperties: false
> > @@ -139,8 +163,11 @@ examples:
> >                  };
> >
> >                  port@1 {
> > +                    #address-cells = <1>;
> > +                    #size-cells = <0>;
> >                      reg = <1>;
> > -                    it6505_out: endpoint {
> > +                    it6505_out: endpoint@0 {
> > +                        reg = <0>;
> >                          remote-endpoint = <&dp_in>;
> >                          data-lanes = <0 1>;
> >                      };
> > @@ -148,3 +175,49 @@ examples:
> >              };
> >          };
> >      };
> > +  - |
> > +    #include <dt-bindings/interrupt-controller/irq.h>
> > +
> > +    i2c3 {
>
> Just i2c

Will fix in v8.
>
> Best regards,
> Krzysztof
>

Best regards,
Pin-yen

[PATCH v7 8/9] drm/bridge: it6505: Fix Kconfig indentation

[Pin-yen Lin]

Replace the spaces with tab characters in the Kconfig file.

Signed-off-by: Pin-yen Lin <treapking@chromium.org>
---

Changes in v7:
- New in v7

 drivers/gpu/drm/bridge/Kconfig | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index 57946d80b02d..737578dd57ed 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -85,19 +85,19 @@ config DRM_FSL_LDB
 	  Support for i.MX8MP DPI-to-LVDS on-SoC encoder.
 
 config DRM_ITE_IT6505
-        tristate "ITE IT6505 DisplayPort bridge"
-        depends on OF
+	tristate "ITE IT6505 DisplayPort bridge"
+	depends on OF
 	select DRM_DISPLAY_DP_HELPER
 	select DRM_DISPLAY_HDCP_HELPER
 	select DRM_DISPLAY_HELPER
-        select DRM_DP_AUX_BUS
-        select DRM_KMS_HELPER
-        select DRM_DP_HELPER
-        select EXTCON
-        select CRYPTO
-        select CRYPTO_HASH
-        help
-          ITE IT6505 DisplayPort bridge chip driver.
+	select DRM_DP_AUX_BUS
+	select DRM_KMS_HELPER
+	select DRM_DP_HELPER
+	select EXTCON
+	select CRYPTO
+	select CRYPTO_HASH
+	help
+	  ITE IT6505 DisplayPort bridge chip driver.
 
 config DRM_LONTIUM_LT8912B
 	tristate "Lontium LT8912B DSI/HDMI bridge"
-- 
2.39.0.314.g84b9a713c41-goog

[PATCH v7 9/9] drm/bridge: it6505: Register Type C mode switches

[Pin-yen Lin]

Register USB Type-C mode switches when the "mode-switch" property and
relevant port are available in Device Tree. Configure the "lane_swap"
state based on the entered alternate mode for a specific Type-C
connector, which ends up updating the lane swap registers of the it6505
chip.

Signed-off-by: Pin-yen Lin <treapking@chromium.org>

---

Changes in v7:
- Fixed style issues in it6505 driver
- Removed the redundant sleep in it6505 driver
- Removed DT property validation in it6505 driver
- Rebased to drm-misc-next
- Extracted common codes to another commit

Changes in v6:
- Changed it6505_typec_mux_set callback function to accommodate with
  the latest drm-misc patches
- Changed the driver implementation to accommodate with the new binding
- Squashed to a single patch

 drivers/gpu/drm/bridge/Kconfig      |   1 +
 drivers/gpu/drm/bridge/ite-it6505.c | 119 +++++++++++++++++++++++++++-
 2 files changed, 116 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index 737578dd57ed..33803f581562 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -87,6 +87,7 @@ config DRM_FSL_LDB
 config DRM_ITE_IT6505
 	tristate "ITE IT6505 DisplayPort bridge"
 	depends on OF
+	depends on TYPEC || TYPEC=n
 	select DRM_DISPLAY_DP_HELPER
 	select DRM_DISPLAY_HDCP_HELPER
 	select DRM_DISPLAY_HELPER
diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
index 9cda2df21b88..d9be09e889e2 100644
--- a/drivers/gpu/drm/bridge/ite-it6505.c
+++ b/drivers/gpu/drm/bridge/ite-it6505.c
@@ -17,6 +17,8 @@
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
 #include <linux/types.h>
+#include <linux/usb/typec_dp.h>
+#include <linux/usb/typec_mux.h>
 #include <linux/wait.h>
 
 #include <crypto/hash.h>
@@ -28,6 +30,7 @@
 #include <drm/drm_crtc.h>
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_edid.h>
+#include <drm/drm_of.h>
 #include <drm/drm_print.h>
 #include <drm/drm_probe_helper.h>
 
@@ -455,6 +458,7 @@ struct it6505 {
 	struct delayed_work delayed_audio;
 	struct it6505_audio_data audio;
 	struct dentry *debugfs;
+	struct drm_dp_typec_switch_desc switch_desc;
 
 	/* it6505 driver hold option */
 	bool enable_drv_hold;
@@ -3346,12 +3350,105 @@ static void it6505_shutdown(struct i2c_client *client)
 		it6505_lane_off(it6505);
 }
 
+static void it6505_typec_ports_update(struct it6505 *it6505)
+{
+	struct drm_dp_typec_switch_desc switch_desc = it6505->switch_desc;
+
+	/* Check if both ports available and do nothing to retain the current one */
+	if (switch_desc.typec_ports[0].dp_connected && switch_desc.typec_ports[1].dp_connected)
+		return;
+
+	if (switch_desc.typec_ports[0].dp_connected)
+		it6505->lane_swap = false;
+	else if (switch_desc.typec_ports[1].dp_connected)
+		it6505->lane_swap = true;
+}
+
+static int it6505_typec_mux_set(struct typec_mux_dev *mux,
+				struct typec_mux_state *state)
+{
+	struct drm_dp_typec_port_data *port_data = typec_mux_get_drvdata(mux);
+	struct it6505 *it6505 = (struct it6505 *) port_data->data;
+	struct device *dev = &it6505->client->dev;
+	struct drm_dp_typec_switch_desc switch_desc = it6505->switch_desc;
+	bool old_dp_connected, new_dp_connected;
+
+	if (switch_desc.num_typec_switches == 1)
+		return 0;
+
+	mutex_lock(&it6505->extcon_lock);
+
+	old_dp_connected = switch_desc.typec_ports[0].dp_connected ||
+			   switch_desc.typec_ports[1].dp_connected;
+
+	port_data->dp_connected = state->alt &&
+				  state->alt->svid == USB_TYPEC_DP_SID &&
+				  state->alt->mode == USB_TYPEC_DP_MODE;
+
+	dev_dbg(dev, "mux_set dp_connected: c0=%d, c1=%d\n",
+		switch_desc.typec_ports[0].dp_connected, switch_desc.typec_ports[1].dp_connected);
+
+	new_dp_connected = switch_desc.typec_ports[0].dp_connected ||
+			   switch_desc.typec_ports[1].dp_connected;
+
+	if (it6505->enable_drv_hold) {
+		dev_dbg(dev, "enable driver hold\n");
+		goto unlock;
+	}
+
+	it6505_typec_ports_update(it6505);
+
+	if (!old_dp_connected && new_dp_connected) {
+		int ret = pm_runtime_get_sync(dev);
+
+		/*
+		 * pm_runtime_force_suspend() disables runtime PM when the
+		 * system enters suspend state. But on system resume, mux_set
+		 * can be triggered before pm_runtime_force_resume() re-enables
+		 * runtime PM. This makes the bridge stay powered off if the
+		 * downstream display is connected when the system is suspended.
+		 * Handling the error here to make sure the bridge is powered
+		 * on, and leave the PM runtime usage count incremented so
+		 * the future runtime PM calls is balanced.
+		 */
+		if (ret < 0)
+			it6505_poweron(it6505);
+
+		complete_all(&it6505->extcon_completion);
+	}
+
+	if (old_dp_connected && !new_dp_connected) {
+		reinit_completion(&it6505->extcon_completion);
+		pm_runtime_put_sync(dev);
+		if (it6505->bridge.dev)
+			drm_helper_hpd_irq_event(it6505->bridge.dev);
+		memset(it6505->dpcd, 0, sizeof(it6505->dpcd));
+	}
+
+unlock:
+	mutex_unlock(&it6505->extcon_lock);
+	return 0;
+}
+
+static void it6505_unregister_typec_switches(struct it6505 *it6505)
+{
+	drm_dp_unregister_typec_switches(&it6505->switch_desc);
+}
+
+static int it6505_register_typec_switches(struct device *dev, struct it6505 *it6505)
+{
+	struct device_node *port = of_graph_get_port_by_id(dev->of_node, 1);
+
+	return drm_dp_register_typec_switches(dev, port, &it6505->switch_desc,
+					      it6505, it6505_typec_mux_set);
+}
+
 static int it6505_i2c_probe(struct i2c_client *client)
 {
 	struct it6505 *it6505;
 	struct device *dev = &client->dev;
 	struct extcon_dev *extcon;
-	int err, intp_irq;
+	int err, intp_irq, ret;
 
 	it6505 = devm_kzalloc(&client->dev, sizeof(*it6505), GFP_KERNEL);
 	if (!it6505)
@@ -3371,11 +3468,24 @@ static int it6505_i2c_probe(struct i2c_client *client)
 	if (PTR_ERR(extcon) == -EPROBE_DEFER)
 		return -EPROBE_DEFER;
 	if (IS_ERR(extcon)) {
-		dev_err(dev, "can not get extcon device!");
-		return PTR_ERR(extcon);
+		if (PTR_ERR(extcon) != -ENODEV)
+			dev_warn(dev, "Cannot get extcon device: %ld\n",
+				 PTR_ERR(extcon));
+		it6505->extcon = NULL;
+	} else {
+		it6505->extcon = extcon;
 	}
 
-	it6505->extcon = extcon;
+	ret = it6505_register_typec_switches(dev, it6505);
+	if (ret) {
+		if (ret != -ENODEV)
+			dev_warn(dev, "Didn't register Type-C switches, err: %d\n",
+				 ret);
+		if (!it6505->extcon) {
+			dev_err(dev, "Both extcon and typec-switch are not registered.\n");
+			return -EINVAL;
+		}
+	}
 
 	it6505->regmap = devm_regmap_init_i2c(client, &it6505_regmap_config);
 	if (IS_ERR(it6505->regmap)) {
@@ -3447,6 +3557,7 @@ static void it6505_i2c_remove(struct i2c_client *client)
 	it6505_debugfs_remove(it6505);
 	it6505_poweroff(it6505);
 	it6505_remove_edid(it6505);
+	it6505_unregister_typec_switches(it6505);
 }
 
 static const struct i2c_device_id it6505_id[] = {
-- 
2.39.0.314.g84b9a713c41-goog