[PATCH 6/8] platform/chrome: cros_ec_typec: Displayport support

Abhishek Pandit-Subedi posted 8 patches 2 months ago
There is a newer version of this series
[PATCH 6/8] platform/chrome: cros_ec_typec: Displayport support
Posted by Abhishek Pandit-Subedi 2 months ago
Add support for entering and exiting displayport alt-mode on systems
using AP driven alt-mode.

Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
---

 MAINTAINERS                                   |   5 +-
 drivers/platform/chrome/Makefile              |   2 +
 drivers/platform/chrome/cros_ec_typec.c       |  13 +-
 drivers/platform/chrome/cros_ec_typec.h       |   1 +
 drivers/platform/chrome/cros_typec_altmode.h  |  34 +++
 .../platform/chrome/cros_typec_displayport.c  | 247 ++++++++++++++++++
 6 files changed, 299 insertions(+), 3 deletions(-)
 create mode 100644 drivers/platform/chrome/cros_typec_altmode.h
 create mode 100644 drivers/platform/chrome/cros_typec_displayport.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 10430778c998..d8baf38cacc6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5282,11 +5282,12 @@ F:	include/linux/platform_data/cros_usbpd_notify.h
 
 CHROMEOS EC USB TYPE-C DRIVER
 M:	Prashant Malani <pmalani@chromium.org>
+M:	Benson Leung <bleung@chromium.org>
+M:	Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
 L:	chrome-platform@lists.linux.dev
 S:	Maintained
 F:	drivers/platform/chrome/cros_ec_typec.*
-F:	drivers/platform/chrome/cros_typec_switch.c
-F:	drivers/platform/chrome/cros_typec_vdm.*
+F:	drivers/platform/chrome/cros_typec_*
 
 CHROMEOS HPS DRIVER
 M:	Dan Callaghan <dcallagh@chromium.org>
diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile
index 2dcc6ccc2302..fe6c5234ac27 100644
--- a/drivers/platform/chrome/Makefile
+++ b/drivers/platform/chrome/Makefile
@@ -18,7 +18,9 @@ obj-$(CONFIG_CROS_EC_SPI)		+= cros_ec_spi.o
 obj-$(CONFIG_CROS_EC_UART)		+= cros_ec_uart.o
 cros_ec_lpcs-objs			:= cros_ec_lpc.o cros_ec_lpc_mec.o
 cros-ec-typec-objs			:= cros_ec_typec.o cros_typec_vdm.o
+cros-ec-typec-$(CONFIG_TYPEC_DP_ALTMODE) += cros_typec_displayport.o
 obj-$(CONFIG_CROS_EC_TYPEC)		+= cros-ec-typec.o
+
 obj-$(CONFIG_CROS_EC_LPC)		+= cros_ec_lpcs.o
 obj-$(CONFIG_CROS_EC_PROTO)		+= cros_ec_proto.o cros_ec_trace.o
 obj-$(CONFIG_CROS_KBD_LED_BACKLIGHT)	+= cros_kbd_led_backlight.o
diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
index 6c0228981627..f9221d0d95f5 100644
--- a/drivers/platform/chrome/cros_ec_typec.c
+++ b/drivers/platform/chrome/cros_ec_typec.c
@@ -18,6 +18,7 @@
 
 #include "cros_ec_typec.h"
 #include "cros_typec_vdm.h"
+#include "cros_typec_altmode.h"
 
 #define DRV_NAME "cros-ec-typec"
 
@@ -293,12 +294,16 @@ static int cros_typec_register_port_altmodes(struct cros_typec_data *typec,
 	desc.svid = USB_TYPEC_DP_SID;
 	desc.mode = USB_TYPEC_DP_MODE;
 	desc.vdo = DP_PORT_VDO;
-	amode = typec_port_register_altmode(port->port, &desc);
+	amode = cros_typec_register_displayport(port, &desc,
+						typec->ap_driven_altmode);
 	if (IS_ERR(amode))
 		return PTR_ERR(amode);
 	port->port_altmode[CROS_EC_ALTMODE_DP] = amode;
+
+#if !IS_ENABLED(CONFIG_TYPEC_DP_ALTMODE)
 	typec_altmode_set_drvdata(amode, port);
 	amode->ops = &port_amode_ops;
+#endif
 
 	/*
 	 * Register TBT compatibility alt mode. The EC will not enter the mode
@@ -575,6 +580,10 @@ static int cros_typec_enable_dp(struct cros_typec_data *typec,
 	if (!ret)
 		ret = typec_mux_set(port->mux, &port->state);
 
+	if (!ret)
+		cros_typec_displayport_status_update(port->state.alt,
+						     port->state.data);
+
 	return ret;
 }
 
@@ -1254,6 +1263,8 @@ static int cros_typec_probe(struct platform_device *pdev)
 
 	typec->typec_cmd_supported = cros_ec_check_features(ec_dev, EC_FEATURE_TYPEC_CMD);
 	typec->needs_mux_ack = cros_ec_check_features(ec_dev, EC_FEATURE_TYPEC_MUX_REQUIRE_AP_ACK);
+	typec->ap_driven_altmode = cros_ec_check_features(
+		ec_dev, EC_FEATURE_TYPEC_REQUIRE_AP_MODE_ENTRY);
 
 	ret = cros_ec_cmd(typec->ec, 0, EC_CMD_USB_PD_PORTS, NULL, 0,
 			  &resp, sizeof(resp));
diff --git a/drivers/platform/chrome/cros_ec_typec.h b/drivers/platform/chrome/cros_ec_typec.h
index deda180a646f..9fd5342bb0ad 100644
--- a/drivers/platform/chrome/cros_ec_typec.h
+++ b/drivers/platform/chrome/cros_ec_typec.h
@@ -39,6 +39,7 @@ struct cros_typec_data {
 	struct work_struct port_work;
 	bool typec_cmd_supported;
 	bool needs_mux_ack;
+	bool ap_driven_altmode;
 };
 
 /* Per port data. */
diff --git a/drivers/platform/chrome/cros_typec_altmode.h b/drivers/platform/chrome/cros_typec_altmode.h
new file mode 100644
index 000000000000..a8b37a18c83a
--- /dev/null
+++ b/drivers/platform/chrome/cros_typec_altmode.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef __CROS_TYPEC_ALTMODE_H__
+#define __CROS_TYPEC_ALTMODE_H__
+
+struct cros_typec_port;
+struct typec_altmode;
+struct typec_altmode_desc;
+struct typec_displayport_data;
+
+#if IS_ENABLED(CONFIG_TYPEC_DP_ALTMODE)
+struct typec_altmode *
+cros_typec_register_displayport(struct cros_typec_port *port,
+				struct typec_altmode_desc *desc,
+				bool ap_mode_entry);
+
+int cros_typec_displayport_status_update(struct typec_altmode *altmode,
+					 struct typec_displayport_data *data);
+#else
+struct typec_altmode *
+cros_typec_register_displayport(struct cros_typec_port *port,
+				struct typec_altmode_desc *desc,
+				bool ap_mode_entry)
+{
+	return typec_port_register_altmode(port->port, desc);
+}
+
+int cros_typec_displayport_status_update(struct typec_altmode *altmode,
+					 struct typec_displayport_data *data)
+{
+	return 0;
+}
+#endif
+#endif /* __CROS_TYPEC_ALTMODE_H__ */
diff --git a/drivers/platform/chrome/cros_typec_displayport.c b/drivers/platform/chrome/cros_typec_displayport.c
new file mode 100644
index 000000000000..bccd57290601
--- /dev/null
+++ b/drivers/platform/chrome/cros_typec_displayport.c
@@ -0,0 +1,247 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Alt-mode implementation for Displayport on ChromeOS EC.
+ *
+ * Copyright 2024 Google LLC
+ * Author: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
+ */
+#include "cros_ec_typec.h"
+
+#include <linux/usb/typec_dp.h>
+#include <linux/usb/pd_vdo.h>
+
+#include "cros_typec_altmode.h"
+
+struct typec_dp_data {
+	struct typec_displayport_data data;
+	struct work_struct work;
+
+	struct cros_typec_port *port;
+	struct typec_altmode *alt;
+	bool ap_mode_entry;
+	bool configured;
+	bool pending_status_update;
+
+	u32 header;
+	u32 *vdo_data;
+	u8 vdo_size;
+};
+
+static void cros_typec_displayport_work(struct work_struct *work)
+{
+	struct typec_dp_data *data =
+		container_of(work, struct typec_dp_data, work);
+
+	if (typec_altmode_vdm(data->alt, data->header, data->vdo_data,
+			      data->vdo_size))
+		dev_err(&data->alt->dev, "VDM 0x%x failed", data->header);
+
+	data->header = 0;
+	data->vdo_data = NULL;
+	data->vdo_size = 0;
+}
+
+static int cros_typec_displayport_enter(struct typec_altmode *alt, u32 *vdo)
+{
+	struct typec_dp_data *data = typec_altmode_get_drvdata(alt);
+	struct ec_params_typec_control req = {
+		.port = data->port->port_num,
+		.command = TYPEC_CONTROL_COMMAND_ENTER_MODE,
+		.mode_to_enter = CROS_EC_ALTMODE_DP,
+	};
+	int svdm_version;
+	int ret;
+
+	if (!data->ap_mode_entry) {
+		const struct typec_altmode *partner =
+			typec_altmode_get_partner(alt);
+		dev_warn(&partner->dev,
+			 "EC does not support ap driven mode entry\n");
+		return -EOPNOTSUPP;
+	}
+
+	ret = cros_ec_cmd(data->port->typec_data->ec, 0, EC_CMD_TYPEC_CONTROL,
+			  &req, sizeof(req), NULL, 0);
+	if (ret < 0)
+		return ret;
+
+	svdm_version = typec_altmode_get_svdm_version(alt);
+	if (svdm_version < 0)
+		return svdm_version;
+
+	data->header = VDO(USB_TYPEC_DP_SID, 1, svdm_version, CMD_ENTER_MODE);
+	data->header |= VDO_OPOS(USB_TYPEC_DP_MODE);
+	data->header |= VDO_CMDT(CMDT_RSP_ACK);
+
+	data->vdo_data = NULL;
+	data->vdo_size = 1;
+
+	schedule_work(&data->work);
+
+	return ret;
+}
+
+static int cros_typec_displayport_exit(struct typec_altmode *alt)
+{
+	struct typec_dp_data *data = typec_altmode_get_drvdata(alt);
+	struct ec_params_typec_control req = {
+		.port = data->port->port_num,
+		.command = TYPEC_CONTROL_COMMAND_EXIT_MODES,
+	};
+	int svdm_version;
+	int ret;
+
+	if (!data->ap_mode_entry) {
+		const struct typec_altmode *partner =
+			typec_altmode_get_partner(alt);
+		dev_warn(&partner->dev,
+			 "EC does not support ap driven mode entry\n");
+		return -EOPNOTSUPP;
+	}
+
+	ret = cros_ec_cmd(data->port->typec_data->ec, 0, EC_CMD_TYPEC_CONTROL,
+			  &req, sizeof(req), NULL, 0);
+
+	if (ret < 0)
+		return ret;
+
+	svdm_version = typec_altmode_get_svdm_version(alt);
+	if (svdm_version < 0)
+		return svdm_version;
+
+	data->header = VDO(USB_TYPEC_DP_SID, 1, svdm_version, CMD_EXIT_MODE);
+	data->header |= VDO_OPOS(USB_TYPEC_DP_MODE);
+	data->header |= VDO_CMDT(CMDT_RSP_ACK);
+
+	data->vdo_data = NULL;
+	data->vdo_size = 1;
+
+	schedule_work(&data->work);
+
+	return ret;
+}
+
+int cros_typec_displayport_status_update(struct typec_altmode *altmode,
+					 struct typec_displayport_data *data)
+{
+	struct typec_dp_data *dp_data = typec_altmode_get_drvdata(altmode);
+
+	if (!dp_data->pending_status_update) {
+		dev_dbg(&altmode->dev,
+			"Got DPStatus without a pending request");
+		return 0;
+	}
+
+	if (dp_data->configured && dp_data->data.conf != data->conf)
+		dev_dbg(&altmode->dev,
+			"DP Conf doesn't match. Requested 0x%04x, Actual 0x%04x",
+			dp_data->data.conf, data->conf);
+
+	dp_data->header |= VDO_CMDT(CMDT_RSP_ACK);
+	dp_data->data = *data;
+	dp_data->vdo_data = &dp_data->data.status;
+	dp_data->vdo_size = 2;
+	dp_data->pending_status_update = false;
+
+	schedule_work(&dp_data->work);
+	return 0;
+}
+
+static int cros_typec_displayport_vdm(struct typec_altmode *alt, u32 header,
+				      const u32 *data, int count)
+{
+	struct typec_dp_data *dp_data = typec_altmode_get_drvdata(alt);
+
+	int cmd_type = PD_VDO_CMDT(header);
+	int cmd = PD_VDO_CMD(header);
+	int svdm_version;
+
+	if (!dp_data->ap_mode_entry) {
+		const struct typec_altmode *partner =
+			typec_altmode_get_partner(alt);
+		dev_warn(&partner->dev,
+			 "EC does not support ap driven mode entry\n");
+		return -EOPNOTSUPP;
+	}
+
+	svdm_version = typec_altmode_get_svdm_version(alt);
+	if (svdm_version < 0)
+		return svdm_version;
+
+	switch (cmd_type) {
+	case CMDT_INIT:
+		if (PD_VDO_SVDM_VER(header) < svdm_version) {
+			typec_partner_set_svdm_version(dp_data->port->partner,
+						       PD_VDO_SVDM_VER(header));
+			svdm_version = PD_VDO_SVDM_VER(header);
+		}
+
+		dp_data->header = VDO(USB_TYPEC_DP_SID, 1, svdm_version, cmd);
+		dp_data->header |= VDO_OPOS(USB_TYPEC_DP_MODE);
+
+		/*
+		 * DP_CMD_CONFIGURE: We can't actually do anything with the
+		 * provided VDO yet so just send back an ACK.
+		 *
+		 * DP_CMD_STATUS_UPDATE: We wait for Mux changes to send
+		 * DPStatus Acks.
+		 */
+		switch (cmd) {
+		case DP_CMD_CONFIGURE:
+			dp_data->data.conf = *data;
+			dp_data->header |= VDO_CMDT(CMDT_RSP_ACK);
+			dp_data->configured = true;
+			schedule_work(&dp_data->work);
+			break;
+		case DP_CMD_STATUS_UPDATE:
+			dp_data->pending_status_update = true;
+			break;
+		default:
+			dp_data->header |= VDO_CMDT(CMDT_RSP_ACK);
+			schedule_work(&dp_data->work);
+			break;
+		}
+
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static const struct typec_altmode_ops cros_typec_displayport_ops = {
+	.enter = cros_typec_displayport_enter,
+	.exit = cros_typec_displayport_exit,
+	.vdm = cros_typec_displayport_vdm,
+};
+
+struct typec_altmode *
+cros_typec_register_displayport(struct cros_typec_port *port,
+				struct typec_altmode_desc *desc,
+				bool ap_mode_entry)
+{
+	struct typec_altmode *alt;
+	struct typec_dp_data *data;
+
+	alt = typec_port_register_altmode(port->port, desc);
+	if (IS_ERR(alt))
+		return alt;
+
+	data = devm_kzalloc(&alt->dev, sizeof(*data), GFP_KERNEL);
+	if (!data) {
+		typec_unregister_altmode(alt);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	INIT_WORK(&data->work, cros_typec_displayport_work);
+	data->alt = alt;
+	data->port = port;
+	data->ap_mode_entry = ap_mode_entry;
+	data->configured = false;
+
+	typec_altmode_set_ops(alt, &cros_typec_displayport_ops);
+	typec_altmode_set_drvdata(alt, data);
+
+	return alt;
+}
-- 
2.46.0.792.g87dc391469-goog
Re: [PATCH 6/8] platform/chrome: cros_ec_typec: Displayport support
Posted by kernel test robot 2 months ago
Hi Abhishek,

kernel test robot noticed the following build warnings:

[auto build test WARNING on chrome-platform/for-next]
[also build test WARNING on chrome-platform/for-firmware-next usb/usb-testing usb/usb-next usb/usb-linus linus/master v6.11 next-20240927]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Abhishek-Pandit-Subedi/usb-typec-Add-driver-for-Thunderbolt-3-Alternate-Mode/20240926-002931
base:   https://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux.git for-next
patch link:    https://lore.kernel.org/r/20240925092505.6.I142fc0c09df58689b98f0cebf1c5e48b9d4fa800%40changeid
patch subject: [PATCH 6/8] platform/chrome: cros_ec_typec: Displayport support
config: i386-randconfig-001-20240928 (https://download.01.org/0day-ci/archive/20240928/202409281250.dtPQ2TrT-lkp@intel.com/config)
compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240928/202409281250.dtPQ2TrT-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202409281250.dtPQ2TrT-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from drivers/platform/chrome/cros_ec_typec.c:21:
>> drivers/platform/chrome/cros_typec_altmode.h:21:1: warning: no previous prototype for function 'cros_typec_register_displayport' [-Wmissing-prototypes]
      21 | cros_typec_register_displayport(struct cros_typec_port *port,
         | ^
   drivers/platform/chrome/cros_typec_altmode.h:20:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
      20 | struct typec_altmode *
         | ^
         | static 
>> drivers/platform/chrome/cros_typec_altmode.h:28:5: warning: no previous prototype for function 'cros_typec_displayport_status_update' [-Wmissing-prototypes]
      28 | int cros_typec_displayport_status_update(struct typec_altmode *altmode,
         |     ^
   drivers/platform/chrome/cros_typec_altmode.h:28:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
      28 | int cros_typec_displayport_status_update(struct typec_altmode *altmode,
         | ^
         | static 
   2 warnings generated.


vim +/cros_typec_register_displayport +21 drivers/platform/chrome/cros_typec_altmode.h

    10	
    11	#if IS_ENABLED(CONFIG_TYPEC_DP_ALTMODE)
    12	struct typec_altmode *
    13	cros_typec_register_displayport(struct cros_typec_port *port,
    14					struct typec_altmode_desc *desc,
    15					bool ap_mode_entry);
    16	
    17	int cros_typec_displayport_status_update(struct typec_altmode *altmode,
    18						 struct typec_displayport_data *data);
    19	#else
    20	struct typec_altmode *
  > 21	cros_typec_register_displayport(struct cros_typec_port *port,
    22					struct typec_altmode_desc *desc,
    23					bool ap_mode_entry)
    24	{
    25		return typec_port_register_altmode(port->port, desc);
    26	}
    27	
  > 28	int cros_typec_displayport_status_update(struct typec_altmode *altmode,

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Re: [PATCH 6/8] platform/chrome: cros_ec_typec: Displayport support
Posted by Dmitry Baryshkov 2 months ago
On Wed, Sep 25, 2024 at 09:25:07AM GMT, Abhishek Pandit-Subedi wrote:
> Add support for entering and exiting displayport alt-mode on systems
> using AP driven alt-mode.
> 
> Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
> ---
> 
>  MAINTAINERS                                   |   5 +-
>  drivers/platform/chrome/Makefile              |   2 +
>  drivers/platform/chrome/cros_ec_typec.c       |  13 +-
>  drivers/platform/chrome/cros_ec_typec.h       |   1 +
>  drivers/platform/chrome/cros_typec_altmode.h  |  34 +++
>  .../platform/chrome/cros_typec_displayport.c  | 247 ++++++++++++++++++
>  6 files changed, 299 insertions(+), 3 deletions(-)
>  create mode 100644 drivers/platform/chrome/cros_typec_altmode.h
>  create mode 100644 drivers/platform/chrome/cros_typec_displayport.c
> 
> diff --git a/drivers/platform/chrome/cros_typec_altmode.h b/drivers/platform/chrome/cros_typec_altmode.h
> new file mode 100644
> index 000000000000..a8b37a18c83a
> --- /dev/null
> +++ b/drivers/platform/chrome/cros_typec_altmode.h
> @@ -0,0 +1,34 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +
> +#ifndef __CROS_TYPEC_ALTMODE_H__
> +#define __CROS_TYPEC_ALTMODE_H__
> +
> +struct cros_typec_port;
> +struct typec_altmode;
> +struct typec_altmode_desc;
> +struct typec_displayport_data;
> +
> +#if IS_ENABLED(CONFIG_TYPEC_DP_ALTMODE)
> +struct typec_altmode *
> +cros_typec_register_displayport(struct cros_typec_port *port,
> +				struct typec_altmode_desc *desc,
> +				bool ap_mode_entry);
> +
> +int cros_typec_displayport_status_update(struct typec_altmode *altmode,
> +					 struct typec_displayport_data *data);
> +#else

As pointed out by the robot, the stubs should be 'static inline'

> +struct typec_altmode *
> +cros_typec_register_displayport(struct cros_typec_port *port,
> +				struct typec_altmode_desc *desc,
> +				bool ap_mode_entry)
> +{
> +	return typec_port_register_altmode(port->port, desc);
> +}
> +
> +int cros_typec_displayport_status_update(struct typec_altmode *altmode,
> +					 struct typec_displayport_data *data)
> +{
> +	return 0;
> +}
> +#endif
> +#endif /* __CROS_TYPEC_ALTMODE_H__ */

-- 
With best wishes
Dmitry
Re: [PATCH 6/8] platform/chrome: cros_ec_typec: Displayport support
Posted by Heikki Krogerus 2 months ago
> diff --git a/drivers/platform/chrome/cros_typec_altmode.h b/drivers/platform/chrome/cros_typec_altmode.h
> new file mode 100644
> index 000000000000..a8b37a18c83a
> --- /dev/null
> +++ b/drivers/platform/chrome/cros_typec_altmode.h
> @@ -0,0 +1,34 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +
> +#ifndef __CROS_TYPEC_ALTMODE_H__
> +#define __CROS_TYPEC_ALTMODE_H__
> +
> +struct cros_typec_port;
> +struct typec_altmode;
> +struct typec_altmode_desc;
> +struct typec_displayport_data;
> +
> +#if IS_ENABLED(CONFIG_TYPEC_DP_ALTMODE)
> +struct typec_altmode *
> +cros_typec_register_displayport(struct cros_typec_port *port,
> +				struct typec_altmode_desc *desc,
> +				bool ap_mode_entry);
> +
> +int cros_typec_displayport_status_update(struct typec_altmode *altmode,
> +					 struct typec_displayport_data *data);
> +#else
> +struct typec_altmode *

static inline struct typec_altmode *

> +cros_typec_register_displayport(struct cros_typec_port *port,
> +				struct typec_altmode_desc *desc,
> +				bool ap_mode_entry)
> +{
> +	return typec_port_register_altmode(port->port, desc);
> +}
> +
> +int cros_typec_displayport_status_update(struct typec_altmode *altmode,
> +					 struct typec_displayport_data *data)

static inline int

> +{
> +	return 0;
> +}
> +#endif
> +#endif /* __CROS_TYPEC_ALTMODE_H__ */

thanks,

-- 
heikki