diff mbox series

[v2,3/7] usb: typec: Auto enter control for alternate modes

Message ID 20241030142833.v2.3.I439cffc7bf76d94f5850eb85980f1197c4f9154c@changeid (mailing list archive)
State New
Headers show
Series Thunderbolt and DP altmode support for cros-ec-typec | expand

Commit Message

Abhishek Pandit-Subedi Oct. 30, 2024, 9:28 p.m. UTC
Add controls for whether an alternate mode is automatically entered when
a partner connects. The auto_enter control is only available on ports
and applies immediately after a partner connects. The default behavior
is to enable auto enter and drivers must explicitly disable it.

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

(no changes since v1)

 Documentation/ABI/testing/sysfs-bus-typec |  9 +++++++
 drivers/usb/typec/altmodes/displayport.c  |  6 +++--
 drivers/usb/typec/altmodes/thunderbolt.c  |  3 ++-
 drivers/usb/typec/class.c                 | 31 +++++++++++++++++++++++
 include/linux/usb/typec.h                 |  2 ++
 include/linux/usb/typec_altmode.h         |  2 ++
 6 files changed, 50 insertions(+), 3 deletions(-)

Comments

Heikki Krogerus Oct. 31, 2024, 2:33 p.m. UTC | #1
On Wed, Oct 30, 2024 at 02:28:34PM -0700, Abhishek Pandit-Subedi wrote:
> Add controls for whether an alternate mode is automatically entered when
> a partner connects. The auto_enter control is only available on ports
> and applies immediately after a partner connects. The default behavior
> is to enable auto enter and drivers must explicitly disable it.
> 
> Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
> ---
> 
> (no changes since v1)
> 
>  Documentation/ABI/testing/sysfs-bus-typec |  9 +++++++
>  drivers/usb/typec/altmodes/displayport.c  |  6 +++--
>  drivers/usb/typec/altmodes/thunderbolt.c  |  3 ++-
>  drivers/usb/typec/class.c                 | 31 +++++++++++++++++++++++
>  include/linux/usb/typec.h                 |  2 ++
>  include/linux/usb/typec_altmode.h         |  2 ++
>  6 files changed, 50 insertions(+), 3 deletions(-)
> 
> diff --git a/Documentation/ABI/testing/sysfs-bus-typec b/Documentation/ABI/testing/sysfs-bus-typec
> index 205d9c91e2e1..f09d05727b82 100644
> --- a/Documentation/ABI/testing/sysfs-bus-typec
> +++ b/Documentation/ABI/testing/sysfs-bus-typec
> @@ -12,6 +12,15 @@ Description:
>  
>  		Valid values are boolean.
>  
> +What:		/sys/bus/typec/devices/.../auto_enter
> +Date:		September 2024
> +Contact:	Heikki Krogerus <heikki.krogerus@linux.intel.com>
> +Description:
> +		Controls whether a mode will be automatically entered when a partner is
> +		connected.
> +
> +		This field is only valid and displayed on a port. Valid values are boolean.

So, why can't this be controlled with the "active" property of the
port altmode instead? That's why it's there.

Sorry if I missed something in v1 related to this question.

thanks,
diff mbox series

Patch

diff --git a/Documentation/ABI/testing/sysfs-bus-typec b/Documentation/ABI/testing/sysfs-bus-typec
index 205d9c91e2e1..f09d05727b82 100644
--- a/Documentation/ABI/testing/sysfs-bus-typec
+++ b/Documentation/ABI/testing/sysfs-bus-typec
@@ -12,6 +12,15 @@  Description:
 
 		Valid values are boolean.
 
+What:		/sys/bus/typec/devices/.../auto_enter
+Date:		September 2024
+Contact:	Heikki Krogerus <heikki.krogerus@linux.intel.com>
+Description:
+		Controls whether a mode will be automatically entered when a partner is
+		connected.
+
+		This field is only valid and displayed on a port. Valid values are boolean.
+
 What:		/sys/bus/typec/devices/.../description
 Date:		July 2018
 Contact:	Heikki Krogerus <heikki.krogerus@linux.intel.com>
diff --git a/drivers/usb/typec/altmodes/displayport.c b/drivers/usb/typec/altmodes/displayport.c
index 2f03190a9873..62263f1d3a72 100644
--- a/drivers/usb/typec/altmodes/displayport.c
+++ b/drivers/usb/typec/altmodes/displayport.c
@@ -767,8 +767,10 @@  int dp_altmode_probe(struct typec_altmode *alt)
 	if (plug)
 		typec_altmode_set_drvdata(plug, dp);
 
-	dp->state = plug ? DP_STATE_ENTER_PRIME : DP_STATE_ENTER;
-	schedule_work(&dp->work);
+	if (port->auto_enter) {
+		dp->state = plug ? DP_STATE_ENTER_PRIME : DP_STATE_ENTER;
+		schedule_work(&dp->work);
+	}
 
 	return 0;
 }
diff --git a/drivers/usb/typec/altmodes/thunderbolt.c b/drivers/usb/typec/altmodes/thunderbolt.c
index 8380b22d26a7..181892bf1225 100644
--- a/drivers/usb/typec/altmodes/thunderbolt.c
+++ b/drivers/usb/typec/altmodes/thunderbolt.c
@@ -212,6 +212,7 @@  static const struct typec_altmode_ops tbt_altmode_ops = {
 
 static int tbt_altmode_probe(struct typec_altmode *alt)
 {
+	const struct typec_altmode *port = typec_altmode_get_partner(alt);
 	struct tbt_altmode *tbt;
 
 	tbt = devm_kzalloc(&alt->dev, sizeof(*tbt), GFP_KERNEL);
@@ -226,7 +227,7 @@  static int tbt_altmode_probe(struct typec_altmode *alt)
 	typec_altmode_set_drvdata(alt, tbt);
 	typec_altmode_set_ops(alt, &tbt_altmode_ops);
 
-	if (tbt_ready(alt)) {
+	if (port->auto_enter && tbt_ready(alt)) {
 		if (tbt->plug[TYPEC_PLUG_SOP_PP])
 			tbt->state = TBT_STATE_SOP_PP_ENTER;
 		else if (tbt->plug[TYPEC_PLUG_SOP_P])
diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
index 85494b9f7502..e74f835c6859 100644
--- a/drivers/usb/typec/class.c
+++ b/drivers/usb/typec/class.c
@@ -403,6 +403,31 @@  static ssize_t active_store(struct device *dev, struct device_attribute *attr,
 }
 static DEVICE_ATTR_RW(active);
 
+static ssize_t
+auto_enter_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct typec_altmode *alt = to_typec_altmode(dev);
+
+	return sprintf(buf, "%s\n", alt->auto_enter ? "yes" : "no");
+}
+
+static ssize_t auto_enter_store(struct device *dev, struct device_attribute *attr,
+			    const char *buf, size_t size)
+{
+	struct typec_altmode *adev = to_typec_altmode(dev);
+	bool auto_enter;
+	int ret;
+
+	ret = kstrtobool(buf, &auto_enter);
+	if (ret)
+		return ret;
+
+	adev->auto_enter = auto_enter;
+
+	return size;
+}
+static DEVICE_ATTR_RW(auto_enter);
+
 static ssize_t
 supported_roles_show(struct device *dev, struct device_attribute *attr,
 		     char *buf)
@@ -446,6 +471,7 @@  static DEVICE_ATTR_RO(svid);
 
 static struct attribute *typec_altmode_attrs[] = {
 	&dev_attr_active.attr,
+	&dev_attr_auto_enter.attr,
 	&dev_attr_mode.attr,
 	&dev_attr_svid.attr,
 	&dev_attr_vdo.attr,
@@ -461,6 +487,10 @@  static umode_t typec_altmode_attr_is_visible(struct kobject *kobj,
 		if (!adev->ops || !adev->ops->activate)
 			return 0444;
 
+	if (attr == &dev_attr_auto_enter.attr)
+		if (!is_typec_port(adev->dev.parent))
+			return 0;
+
 	return attr->mode;
 }
 
@@ -564,6 +594,7 @@  typec_register_altmode(struct device *parent,
 	if (is_port) {
 		alt->attrs[3] = &dev_attr_supported_roles.attr;
 		alt->adev.active = true; /* Enabled by default */
+		alt->adev.auto_enter = !desc->no_auto_enter;
 	}
 
 	sprintf(alt->group_name, "mode%d", desc->mode);
diff --git a/include/linux/usb/typec.h b/include/linux/usb/typec.h
index d616b8807000..5336b7c92ca4 100644
--- a/include/linux/usb/typec.h
+++ b/include/linux/usb/typec.h
@@ -139,6 +139,7 @@  int typec_cable_set_identity(struct typec_cable *cable);
  * @svid: Standard or Vendor ID
  * @mode: Index of the Mode
  * @vdo: VDO returned by Discover Modes USB PD command
+ * @no_auto_enter: Only for ports. Disables auto enter which is default behavior.
  * @roles: Only for ports. DRP if the mode is available in both roles
  *
  * Description of an Alternate Mode which a connector, cable plug or partner
@@ -148,6 +149,7 @@  struct typec_altmode_desc {
 	u16			svid;
 	u8			mode;
 	u32			vdo;
+	bool			no_auto_enter;
 	/* Only used with ports */
 	enum typec_port_data	roles;
 };
diff --git a/include/linux/usb/typec_altmode.h b/include/linux/usb/typec_altmode.h
index b3c0866ea70f..ab7c3ebe4926 100644
--- a/include/linux/usb/typec_altmode.h
+++ b/include/linux/usb/typec_altmode.h
@@ -18,6 +18,7 @@  struct typec_altmode_ops;
  * @mode: Index of the Mode
  * @vdo: VDO returned by Discover Modes USB PD command
  * @active: Tells has the mode been entered or not
+ * @auto_enter: Tells whether to auto-enter mode (only valid for port mode).
  * @desc: Optional human readable description of the mode
  * @ops: Operations vector from the driver
  * @cable_ops: Cable operations vector from the driver.
@@ -28,6 +29,7 @@  struct typec_altmode {
 	int				mode;
 	u32				vdo;
 	unsigned int			active:1;
+	unsigned int			auto_enter:1;
 
 	char				*desc;
 	const struct typec_altmode_ops	*ops;