[PATCH v4 7/7] drm/bridge: anx7625: Add typec_mux_set callback function

[Prashant Malani <pmalani@chromium.org>]

From: Pin-Yen Lin <treapking@chromium.org>

Add the callback function when the driver receives state
changes of the Type-C port. The callback function configures the
crosspoint switch of the anx7625 bridge chip, which can change the
output pins of the signals according to the port state.

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Tested-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Signed-off-by: Pin-Yen Lin <treapking@chromium.org>
Signed-off-by: Prashant Malani <pmalani@chromium.org>
---

Changes since v3:
- Added Reviewed-by tag from Angelo.

Changes since v2:
- Moved num_typec_switches check to beginning of function
- Made dp_connected assignments fit on one line (and removed unnecessary
  parentheses)
- Added Reviewed-by and Tested-by tags.

Changes since v1:
- No changes.

 drivers/gpu/drm/bridge/analogix/anx7625.c | 56 +++++++++++++++++++++++
 drivers/gpu/drm/bridge/analogix/anx7625.h | 13 ++++++
 2 files changed, 69 insertions(+)

diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index bd21f159b973..5992fc8beeeb 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -15,6 +15,7 @@
 #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>
 
@@ -2582,9 +2583,64 @@ 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)
+{
+	if (ctx->typec_ports[0].dp_connected && ctx->typec_ports[1].dp_connected)
+		/* Both ports available, do nothing to retain the current one. */
+		return;
+	else if (ctx->typec_ports[0].dp_connected)
+		anx7625_set_crosspoint_switch(ctx, TYPEC_ORIENTATION_NORMAL);
+	else if (ctx->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 anx7625_port_data *data = typec_mux_get_drvdata(mux);
+	struct anx7625_data *ctx = data->ctx;
+	struct device *dev = &ctx->client->dev;
+	bool new_dp_connected, old_dp_connected;
+
+	if (ctx->num_typec_switches == 1)
+		return 0;
+
+	old_dp_connected = ctx->typec_ports[0].dp_connected || ctx->typec_ports[1].dp_connected;
+
+	dev_dbg(dev, "mux_set dp_connected: c0=%d, c1=%d\n",
+		ctx->typec_ports[0].dp_connected, ctx->typec_ports[1].dp_connected);
+
+	data->dp_connected = (state->alt && state->alt->svid == USB_TYPEC_DP_SID &&
+			      state->alt->mode == USB_TYPEC_DP_MODE);
+
+	new_dp_connected = ctx->typec_ports[0].dp_connected || ctx->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;
 }
 
diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.h b/drivers/gpu/drm/bridge/analogix/anx7625.h
index 76cfc64f7574..7d6c6fdf9a3a 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 ********/
 
 /***************************************************************/
@@ -444,6 +456,7 @@ struct anx7625_i2c_client {
 };
 
 struct anx7625_port_data {
+	bool dp_connected;
 	struct typec_mux_dev *typec_mux;
 	struct anx7625_data *ctx;
 };
-- 
2.36.1.476.g0c4daa206d-goog