diff mbox series

platform/chrome: cros_ec_typec: Add support for setting USB mode via sysfs

Message ID 20250210130419.4110130-1-akuchynski@chromium.org (mailing list archive)
State Accepted
Commit 9fc83373f0ffb8834da48b1446a5c2fef9525bb1
Headers show
Series platform/chrome: cros_ec_typec: Add support for setting USB mode via sysfs | expand

Commit Message

Andrei Kuchynski Feb. 10, 2025, 1:04 p.m. UTC
This patch implements USB mode setting via a sysfs interface in
cros_ec_typec driver. User-space applications can now change the current
USB mode by writing to "usb_mode" sysfs entry, replacing the previous
ioctl-based method.
The embedded controller (EC) currently supports only entering USB4 mode
and exiting all modes (including altmodes). Both of these operations
trigger Data Reset Message, even if no USB Mode is active.
Additionally, the patch exposes the USB modes supported by the port via
"usb_capability" sysfs attribute.

Signed-off-by: Andrei Kuchynski <akuchynski@chromium.org>
---
 drivers/platform/chrome/cros_ec_typec.c | 28 +++++++++++++++++++++++++
 drivers/platform/chrome/cros_ec_typec.h |  1 +
 2 files changed, 29 insertions(+)

Comments

Tzung-Bi Shih Feb. 18, 2025, 2:26 p.m. UTC | #1
On Mon, Feb 10, 2025 at 01:04:19PM +0000, Andrei Kuchynski wrote:
> +static int cros_typec_enter_usb_mode(struct typec_port *tc_port, enum usb_mode mode)
> +{
> +	struct cros_typec_port *port = typec_get_drvdata(tc_port);
> +	struct ec_params_typec_control req = {
> +		.port = port->port_num,
> +		.command = (mode == USB_MODE_USB4) ?
> +			TYPEC_CONTROL_COMMAND_ENTER_MODE : TYPEC_CONTROL_COMMAND_EXIT_MODES,
> +		.mode_to_enter = CROS_EC_ALTMODE_USB4

The symbol `CROS_EC_ALTMODE_USB4` doesn't exist.  On a related note, wouldn't
it always enter CROS_EC_ALTMODE_USB4 if the value is hard-coded here?

> @@ -84,6 +102,13 @@ static int cros_typec_parse_port_props(struct typec_capability *cap,
>  		cap->prefer_role = ret;
>  	}
>  
> +	if (fwnode_property_present(fwnode, "usb2-port"))
> +		cap->usb_capability |= USB_CAPABILITY_USB2;
> +	if (fwnode_property_present(fwnode, "usb3-port"))
> +		cap->usb_capability |= USB_CAPABILITY_USB3;
> +	if (fwnode_property_present(fwnode, "usb4-port"))
> +		cap->usb_capability |= USB_CAPABILITY_USB4;

Are these defined somewhere?  E.g. the bindings?
Andrei Kuchynski Feb. 20, 2025, 1:39 p.m. UTC | #2
On Tue, Feb 18, 2025 at 2:26 PM Tzung-Bi Shih <tzungbi@kernel.org> wrote:
>
> On Mon, Feb 10, 2025 at 01:04:19PM +0000, Andrei Kuchynski wrote:
> > +static int cros_typec_enter_usb_mode(struct typec_port *tc_port, enum usb_mode mode)
> > +{
> > +     struct cros_typec_port *port = typec_get_drvdata(tc_port);
> > +     struct ec_params_typec_control req = {
> > +             .port = port->port_num,
> > +             .command = (mode == USB_MODE_USB4) ?
> > +                     TYPEC_CONTROL_COMMAND_ENTER_MODE : TYPEC_CONTROL_COMMAND_EXIT_MODES,
> > +             .mode_to_enter = CROS_EC_ALTMODE_USB4
>
> The symbol `CROS_EC_ALTMODE_USB4` doesn't exist.  On a related note, wouldn't
> it always enter CROS_EC_ALTMODE_USB4 if the value is hard-coded here?
>

CROS_EC_ALTMODE_USB4 is defined in drivers/platform/chrome/cros_ec_typec.h.
TYPEC_CONTROL_COMMAND_ENTER_MODE command will be sent only if
mode == USB_MODE_USB4 because EC currently only supports entering USB4 mode.
Otherwise, TYPEC_CONTROL_COMMAND_EXIT_MODES is sent, and the mode_to_enter
field is irrelevant for this command.

> > @@ -84,6 +102,13 @@ static int cros_typec_parse_port_props(struct typec_capability *cap,
> >               cap->prefer_role = ret;
> >       }
> >
> > +     if (fwnode_property_present(fwnode, "usb2-port"))
> > +             cap->usb_capability |= USB_CAPABILITY_USB2;
> > +     if (fwnode_property_present(fwnode, "usb3-port"))
> > +             cap->usb_capability |= USB_CAPABILITY_USB3;
> > +     if (fwnode_property_present(fwnode, "usb4-port"))
> > +             cap->usb_capability |= USB_CAPABILITY_USB4;
>
> Are these defined somewhere?  E.g. the bindings?

Unfortunately, property names are set in the ACPI firmware in the same way.
Tzung-Bi Shih Feb. 21, 2025, 1:41 a.m. UTC | #3
On Thu, Feb 20, 2025 at 01:39:57PM +0000, Andrei Kuchynski wrote:
> On Tue, Feb 18, 2025 at 2:26 PM Tzung-Bi Shih <tzungbi@kernel.org> wrote:
> >
> > On Mon, Feb 10, 2025 at 01:04:19PM +0000, Andrei Kuchynski wrote:
> > > +static int cros_typec_enter_usb_mode(struct typec_port *tc_port, enum usb_mode mode)
> > > +{
> > > +     struct cros_typec_port *port = typec_get_drvdata(tc_port);
> > > +     struct ec_params_typec_control req = {
> > > +             .port = port->port_num,
> > > +             .command = (mode == USB_MODE_USB4) ?
> > > +                     TYPEC_CONTROL_COMMAND_ENTER_MODE : TYPEC_CONTROL_COMMAND_EXIT_MODES,
> > > +             .mode_to_enter = CROS_EC_ALTMODE_USB4
> >
> > The symbol `CROS_EC_ALTMODE_USB4` doesn't exist.  On a related note, wouldn't
> > it always enter CROS_EC_ALTMODE_USB4 if the value is hard-coded here?
> >
> 
> CROS_EC_ALTMODE_USB4 is defined in drivers/platform/chrome/cros_ec_typec.h.

I see.  Overlooked that.
Tzung-Bi Shih Feb. 21, 2025, 1:45 a.m. UTC | #4
On Mon, Feb 10, 2025 at 01:04:19PM +0000, Andrei Kuchynski wrote:
> This patch implements USB mode setting via a sysfs interface in
> cros_ec_typec driver. User-space applications can now change the current
> USB mode by writing to "usb_mode" sysfs entry, replacing the previous
> ioctl-based method.
> The embedded controller (EC) currently supports only entering USB4 mode
> and exiting all modes (including altmodes). Both of these operations
> trigger Data Reset Message, even if no USB Mode is active.
> Additionally, the patch exposes the USB modes supported by the port via
> "usb_capability" sysfs attribute.
> 
> [...]

Applied to

    https://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux.git for-next

[1/1] platform/chrome: cros_ec_typec: Add support for setting USB mode via sysfs
      commit: 9fc83373f0ffb8834da48b1446a5c2fef9525bb1

Thanks!
diff mbox series

Patch

diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
index 6ee182101bc9..d2228720991f 100644
--- a/drivers/platform/chrome/cros_ec_typec.c
+++ b/drivers/platform/chrome/cros_ec_typec.c
@@ -42,6 +42,24 @@  static void cros_typec_role_switch_quirk(struct fwnode_handle *fwnode)
 #endif
 }
 
+static int cros_typec_enter_usb_mode(struct typec_port *tc_port, enum usb_mode mode)
+{
+	struct cros_typec_port *port = typec_get_drvdata(tc_port);
+	struct ec_params_typec_control req = {
+		.port = port->port_num,
+		.command = (mode == USB_MODE_USB4) ?
+			TYPEC_CONTROL_COMMAND_ENTER_MODE : TYPEC_CONTROL_COMMAND_EXIT_MODES,
+		.mode_to_enter = CROS_EC_ALTMODE_USB4
+	};
+
+	return cros_ec_cmd(port->typec_data->ec, 0, EC_CMD_TYPEC_CONTROL,
+			  &req, sizeof(req), NULL, 0);
+}
+
+static const struct typec_operations cros_typec_usb_mode_ops = {
+	.enter_usb_mode = cros_typec_enter_usb_mode
+};
+
 static int cros_typec_parse_port_props(struct typec_capability *cap,
 				       struct fwnode_handle *fwnode,
 				       struct device *dev)
@@ -84,6 +102,13 @@  static int cros_typec_parse_port_props(struct typec_capability *cap,
 		cap->prefer_role = ret;
 	}
 
+	if (fwnode_property_present(fwnode, "usb2-port"))
+		cap->usb_capability |= USB_CAPABILITY_USB2;
+	if (fwnode_property_present(fwnode, "usb3-port"))
+		cap->usb_capability |= USB_CAPABILITY_USB3;
+	if (fwnode_property_present(fwnode, "usb4-port"))
+		cap->usb_capability |= USB_CAPABILITY_USB4;
+
 	cros_typec_role_switch_quirk(fwnode);
 
 	cap->fwnode = fwnode;
@@ -379,6 +404,9 @@  static int cros_typec_init_ports(struct cros_typec_data *typec)
 		if (ret < 0)
 			goto unregister_ports;
 
+		cap->driver_data = cros_port;
+		cap->ops = &cros_typec_usb_mode_ops;
+
 		cros_port->port = typec_register_port(dev, cap);
 		if (IS_ERR(cros_port->port)) {
 			ret = PTR_ERR(cros_port->port);
diff --git a/drivers/platform/chrome/cros_ec_typec.h b/drivers/platform/chrome/cros_ec_typec.h
index 9fd5342bb0ad..f9c31f04c102 100644
--- a/drivers/platform/chrome/cros_ec_typec.h
+++ b/drivers/platform/chrome/cros_ec_typec.h
@@ -18,6 +18,7 @@ 
 enum {
 	CROS_EC_ALTMODE_DP = 0,
 	CROS_EC_ALTMODE_TBT,
+	CROS_EC_ALTMODE_USB4,
 	CROS_EC_ALTMODE_MAX,
 };