[PATCH v15 07/10] drm/bridge: anx7625: Register Type C mode switches

[Pin-yen Lin <treapking@chromium.org>]

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

Crosspoint switch can also be used for switching the output signal for
different orientations of a single USB Type-C connector, but the
orientation switch is not implemented yet. A TODO is added for this.

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

---

Changes in v15:
- Swap the definitions in anx7625_typec_port_data
- Add comments about the completion
- Abort the mux_set callback when the switch is unregistered
- Fix style issues

Changes in v14:
- Fix style issues

Changes in v12:
- Fixed style issues in anx7625 driver
- Fixed the inverted orientation setting in anx7625 driver
- Changed "&ctx->client->dev" to "ctx->dev"
- Fix style issues
- Updated the error logs when parsing data-lanes property

Changes in v11:
- Added back "data-lanes" parsing logics
- Removed Kconfig dependency
- Updated the usage of the private data
- Dropped Tested-by tag because of the new changes

Changes in v10:
- Added a TODO for implementing orientation switch for anx7625
- Updated the commit message for the absence of orientation switch
- Fixed typo in the commit message
- Collected Tested-by tag

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/anx7625.c | 157 ++++++++++++++++++++++
 drivers/gpu/drm/bridge/analogix/anx7625.h |  20 +++
 2 files changed, 177 insertions(+)

diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index 76d46db3f8dc..7ed5797e134c 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>
@@ -2570,6 +2572,154 @@ 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)
+{
+	unsigned int i;
+
+	/* Check if both ports available and do nothing to retain the current one */
+	if (ctx->port_data[0].dp_connected && ctx->port_data[1].dp_connected)
+		return;
+
+	for (i = 0; i < 2; i++) {
+		if (ctx->port_data[i].dp_connected)
+			anx7625_set_crosspoint_switch(ctx,
+						      ctx->port_data[i].orientation);
+	}
+}
+
+static int anx7625_typec_mux_set(struct typec_mux_dev *mux,
+				 struct typec_mux_state *state)
+{
+	struct drm_dp_typec_port_data *port = typec_mux_get_drvdata(mux);
+	struct anx7625_data *ctx = port->data;
+	struct device *dev = ctx->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;
+
+	/*
+	 * The completion is called in anx7625_register_typec_switches
+	 * even on errors, so it's safe to wait for completion without timeout.
+	 */
+	wait_for_completion(&ctx->mux_register);
+
+	/* Abort when the switches are unregistered. */
+	if (!ctx->port_data)
+		return -EINVAL;
+
+	old_dp_connected = ctx->port_data[0].dp_connected ||
+			   ctx->port_data[1].dp_connected;
+
+	ctx->port_data[port->port_num].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",
+		ctx->port_data[0].dp_connected, ctx->port_data[1].dp_connected);
+
+	new_dp_connected = ctx->port_data[0].dp_connected ||
+			   ctx->port_data[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);
+	ctx->port_data = NULL;
+}
+
+static int anx7625_register_typec_switches(struct device *dev, struct anx7625_data *ctx)
+{
+	struct device_node *port_node = of_graph_get_port_by_id(dev->of_node, 1);
+	struct drm_dp_typec_switch_desc *switch_desc = &ctx->switch_desc;
+	int ret;
+	u32 dp_lanes[4];
+	unsigned int i, num_lanes;
+
+	/*
+	 * Currently, only mode switch is implemented.
+	 * TODO: Implement Type-C orientation switch for anx7625.
+	 */
+	ret = drm_dp_register_typec_switches(dev, &port_node->fwnode,
+					     &ctx->switch_desc, ctx,
+					     anx7625_typec_mux_set);
+	if (ret)
+		return ret;
+
+	ctx->port_data = devm_kcalloc(dev, switch_desc->num_typec_switches,
+				      sizeof(*ctx->port_data),
+				      GFP_KERNEL);
+	if (!ctx->port_data) {
+		ret = -ENOMEM;
+		goto unregister_mux;
+	}
+
+	for (i = 0; i < switch_desc->num_typec_switches; i++) {
+		struct drm_dp_typec_port_data *port = &switch_desc->typec_ports[i];
+		struct fwnode_handle *fwnode = port->fwnode;
+
+		ret = fwnode_property_count_u32(fwnode, "data-lanes");
+		if (ret < 0) {
+			dev_err(dev,
+				"Error on getting data lanes count from %pfwP: %d\n",
+				fwnode, ret);
+			goto unregister_mux;
+		}
+		num_lanes = ret;
+
+		ret = fwnode_property_read_u32_array(fwnode, "data-lanes",
+						     dp_lanes, num_lanes);
+		if (ret) {
+			dev_err(dev,
+				"Failed to read the data-lanes variable: %d\n",
+				ret);
+			goto unregister_mux;
+		}
+
+		ctx->port_data[i].orientation = dp_lanes[0] < 2 ?
+			TYPEC_ORIENTATION_REVERSE : TYPEC_ORIENTATION_NORMAL;
+		ctx->port_data[i].dp_connected = false;
+	}
+	complete_all(&ctx->mux_register);
+
+	return 0;
+
+unregister_mux:
+	anx7625_unregister_typec_switches(ctx);
+	complete_all(&ctx->mux_register);
+	return ret;
+}
+
 static int anx7625_i2c_probe(struct i2c_client *client)
 {
 	struct anx7625_data *platform;
@@ -2607,6 +2757,7 @@ static int anx7625_i2c_probe(struct i2c_client *client)
 
 	mutex_init(&platform->lock);
 	mutex_init(&platform->hdcp_wq_lock);
+	init_completion(&platform->mux_register);
 
 	INIT_DELAYED_WORK(&platform->hdcp_work, hdcp_check_work_func);
 	platform->hdcp_workqueue = create_workqueue("hdcp workqueue");
@@ -2677,6 +2828,10 @@ 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))
@@ -2728,6 +2883,8 @@ 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 5af819611ebc..291dba62e096 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 ********/
 
 /***************************************************************/
@@ -449,6 +461,11 @@ struct anx7625_i2c_client {
 	struct i2c_client *tcpc_client;
 };
 
+struct anx7625_typec_port_data {
+	enum typec_orientation orientation;
+	bool dp_connected;
+};
+
 struct anx7625_data {
 	struct anx7625_platform_data pdata;
 	struct platform_device *audio_pdev;
@@ -479,6 +496,9 @@ struct anx7625_data {
 	struct drm_connector *connector;
 	struct mipi_dsi_device *dsi;
 	struct drm_dp_aux aux;
+	struct completion mux_register;
+	struct drm_dp_typec_switch_desc switch_desc;
+	struct anx7625_typec_port_data *port_data;
 };
 
 #endif  /* __ANX7625_H__ */
-- 
2.40.0.348.gf938b09366-goog