diff mbox series

[09/10] platform/chrome: cros_ec_typec: Propagate altmode entry result

Message ID 20250616133147.1835939-10-akuchynski@chromium.org
State New
Headers show
Series USB Type-C mode selection | expand

Commit Message

Andrei Kuchynski June 16, 2025, 1:31 p.m. UTC
In the `cros_typec_configure_mux` function, which concludes the DP/TBT
alternate mode entry, the error code should be reported back to the Type-C
mode selection logic. This ensures a detailed result is conveyed to user
space.
To inform partner drivers about the result, the VDM mechanism is used. For
DP altmode, the DP_CMD_STATUS_UPDATE message is utilized, as it is the
final one in the mode entry sequence. For TBT mode, the
TBT_CMD_STATUS_UPDATE message is sent.

Signed-off-by: Andrei Kuchynski <akuchynski@chromium.org>
---
 drivers/platform/chrome/cros_ec_typec.c      |  9 ++++++
 drivers/platform/chrome/cros_typec_altmode.c | 32 ++++++++++++++++++--
 drivers/platform/chrome/cros_typec_altmode.h |  6 ++++
 include/linux/usb/typec_dp.h                 |  2 ++
 4 files changed, 46 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
index 3aed429fde03..a4f338771094 100644
--- a/drivers/platform/chrome/cros_ec_typec.c
+++ b/drivers/platform/chrome/cros_ec_typec.c
@@ -610,6 +610,7 @@  static int cros_typec_enable_dp(struct cros_typec_data *typec,
 	if (!ret)
 		ret = typec_mux_set(port->mux, &port->state);
 
+	dp_data.error = 0;
 	if (!ret)
 		ret = cros_typec_displayport_status_update(port->state.alt,
 							   port->state.data);
@@ -699,8 +700,16 @@  static int cros_typec_configure_mux(struct cros_typec_data *typec, int port_num,
 		ret = cros_typec_enable_usb4(typec, port_num, pd_ctrl);
 	} else if (port->mux_flags & USB_PD_MUX_TBT_COMPAT_ENABLED) {
 		ret = cros_typec_enable_tbt(typec, port_num, pd_ctrl);
+		cros_typec_tbt_status_update(
+			port->port_altmode[CROS_EC_ALTMODE_TBT], ret);
 	} else if (port->mux_flags & USB_PD_MUX_DP_ENABLED) {
 		ret = cros_typec_enable_dp(typec, port_num, pd_ctrl);
+		if (ret) {
+			struct typec_displayport_data dp_data = {.error = ret};
+
+			cros_typec_displayport_status_update(
+				port->port_altmode[CROS_EC_ALTMODE_DP], &dp_data);
+		}
 	} else if (port->mux_flags & USB_PD_MUX_SAFE_MODE) {
 		ret = cros_typec_usb_safe_state(port);
 	} else if (port->mux_flags & USB_PD_MUX_USB_ENABLED) {
diff --git a/drivers/platform/chrome/cros_typec_altmode.c b/drivers/platform/chrome/cros_typec_altmode.c
index 557340b53af0..7ee295cf0c02 100644
--- a/drivers/platform/chrome/cros_typec_altmode.c
+++ b/drivers/platform/chrome/cros_typec_altmode.c
@@ -28,6 +28,7 @@  struct cros_typec_altmode_data {
 
 	u16 sid;
 	u8 mode;
+	int error;
 };
 
 struct cros_typec_dp_data {
@@ -295,9 +296,16 @@  int cros_typec_displayport_status_update(struct typec_altmode *altmode,
 
 	dp_data->data = *data;
 	dp_data->pending_status_update = false;
-	adata->header |= VDO_CMDT(CMDT_RSP_ACK);
-	adata->vdo_data = &dp_data->data.status;
-	adata->vdo_size = 2;
+	if (data->error) {
+		adata->header |= VDO_CMDT(CMDT_RSP_NAK);
+		adata->error = dp_data->data.error;
+		adata->vdo_data = &adata->error;
+		adata->vdo_size = 1;
+	} else {
+		adata->header |= VDO_CMDT(CMDT_RSP_ACK);
+		adata->vdo_data = &dp_data->data.status;
+		adata->vdo_size = 2;
+	}
 	schedule_work(&adata->work);
 
 	mutex_unlock(&adata->lock);
@@ -370,4 +378,22 @@  cros_typec_register_thunderbolt(struct cros_typec_port *port,
 
 	return alt;
 }
+
+int cros_typec_tbt_status_update(struct typec_altmode *alt, int error)
+{
+	struct cros_typec_altmode_data *adata = typec_altmode_get_drvdata(alt);
+
+	mutex_lock(&adata->lock);
+
+	adata->header = VDO(adata->sid, 1, SVDM_VER_2_0, TBT_CMD_STATUS_UPDATE);
+	adata->header |= VDO_CMDT(error ? CMDT_RSP_NAK : CMDT_RSP_ACK);
+	adata->error = error;
+	adata->vdo_data = &adata->error;
+	adata->vdo_size = 1;
+	schedule_work(&adata->work);
+
+	mutex_unlock(&adata->lock);
+
+	return 0;
+}
 #endif
diff --git a/drivers/platform/chrome/cros_typec_altmode.h b/drivers/platform/chrome/cros_typec_altmode.h
index 3f2aa95d065a..848a2b194b34 100644
--- a/drivers/platform/chrome/cros_typec_altmode.h
+++ b/drivers/platform/chrome/cros_typec_altmode.h
@@ -39,6 +39,7 @@  static inline int cros_typec_displayport_status_update(struct typec_altmode *alt
 struct typec_altmode *
 cros_typec_register_thunderbolt(struct cros_typec_port *port,
 				struct typec_altmode_desc *desc);
+int cros_typec_tbt_status_update(struct typec_altmode *alt, int error);
 #else
 static inline struct typec_altmode *
 cros_typec_register_thunderbolt(struct cros_typec_port *port,
@@ -46,6 +47,11 @@  cros_typec_register_thunderbolt(struct cros_typec_port *port,
 {
 	return typec_port_register_altmode(port->port, desc);
 }
+static inline int cros_typec_tbt_status_update(struct typec_altmode *alt,
+					int error)
+{
+	return 0;
+}
 #endif
 
 #endif /* __CROS_TYPEC_ALTMODE_H__ */
diff --git a/include/linux/usb/typec_dp.h b/include/linux/usb/typec_dp.h
index f2da264d9c14..1679f7bb0c75 100644
--- a/include/linux/usb/typec_dp.h
+++ b/include/linux/usb/typec_dp.h
@@ -44,10 +44,12 @@  enum {
  * commands: Status Update and Configure.
  *
  * @status will show for example the status of the HPD signal.
+ * @error will contain the error code, if applicable.
  */
 struct typec_displayport_data {
 	u32 status;
 	u32 conf;
+	int error;
 };
 
 enum {