On Fri, Mar 17, 2023 at 11:42:28AM +0100, Alvin Šipraga wrote:
> From: Alvin Šipraga <alsi@xxxxxxxxxxxxxxx>
>
> The connector child node of the TUSB320 device might be linked with a
> USB OTG controller with USB role switch capability. Add driver support
> for detecting a usb_role_switch and setting its state in the typec
> interrupt handler. This follows similar practice in other drivers in the
> typec subsystem, which this extcon driver can opt-in to.
I'm sorry to be a bit picky here, but I must ask that you don't use
the term USB OTG. It is too confusing - OTG may refer to USB device
controller, USB host controller, or dual-role capable USB controller,
depending on the case, so we need to be specific.
The OTG spec itself is in any case obsolete - USB Type-C and USB PD
specs define their own way of handling the roles, and they are not
compatible with the USB OTG specification(s).
thanks,
> Signed-off-by: Alvin Šipraga <alsi@xxxxxxxxxxxxxxx>
> ---
> v2: remove unused variable as reported by kernel test robot
> ---
> drivers/extcon/extcon-usbc-tusb320.c | 21 +++++++++++++++++++++
> 1 file changed, 21 insertions(+)
>
> diff --git a/drivers/extcon/extcon-usbc-tusb320.c b/drivers/extcon/extcon-usbc-tusb320.c
> index 882d1f48495e..cc2d0ac7c5f6 100644
> --- a/drivers/extcon/extcon-usbc-tusb320.c
> +++ b/drivers/extcon/extcon-usbc-tusb320.c
> @@ -16,6 +16,7 @@
> #include <linux/regmap.h>
> #include <linux/usb/typec.h>
> #include <linux/usb/typec_altmode.h>
> +#include <linux/usb/role.h>
>
> #define TUSB320_REG8 0x8
> #define TUSB320_REG8_CURRENT_MODE_ADVERTISE GENMASK(7, 6)
> @@ -80,6 +81,7 @@ struct tusb320_priv {
> enum typec_port_type port_type;
> enum typec_pwr_opmode pwr_opmode;
> struct fwnode_handle *connector_fwnode;
> + struct usb_role_switch *role_sw;
> };
>
> static const char * const tusb_attached_states[] = {
> @@ -278,6 +280,7 @@ static void tusb320_typec_irq_handler(struct tusb320_priv *priv, u8 reg9)
> struct typec_port *port = priv->port;
> struct device *dev = priv->dev;
> int typec_mode;
> + enum usb_role usb_role;
> enum typec_role pwr_role;
> enum typec_data_role data_role;
> u8 state, mode, accessory;
> @@ -300,11 +303,13 @@ static void tusb320_typec_irq_handler(struct tusb320_priv *priv, u8 reg9)
> switch (state) {
> case TUSB320_ATTACHED_STATE_DFP:
> typec_mode = TYPEC_MODE_USB2;
> + usb_role = USB_ROLE_HOST;
> pwr_role = TYPEC_SOURCE;
> data_role = TYPEC_HOST;
> break;
> case TUSB320_ATTACHED_STATE_UFP:
> typec_mode = TYPEC_MODE_USB2;
> + usb_role = USB_ROLE_DEVICE;
> pwr_role = TYPEC_SINK;
> data_role = TYPEC_DEVICE;
> break;
> @@ -316,6 +321,7 @@ static void tusb320_typec_irq_handler(struct tusb320_priv *priv, u8 reg9)
> if (accessory == TUSB320_REG8_ACCESSORY_CONNECTED_AUDIO ||
> accessory == TUSB320_REG8_ACCESSORY_CONNECTED_ACHRG) {
> typec_mode = TYPEC_MODE_AUDIO;
> + usb_role = USB_ROLE_NONE;
> pwr_role = TYPEC_SINK;
> data_role = TYPEC_DEVICE;
> break;
> @@ -323,12 +329,14 @@ static void tusb320_typec_irq_handler(struct tusb320_priv *priv, u8 reg9)
> TUSB320_REG8_ACCESSORY_CONNECTED_DBGDFP) {
> typec_mode = TYPEC_MODE_DEBUG;
> pwr_role = TYPEC_SOURCE;
> + usb_role = USB_ROLE_HOST;
> data_role = TYPEC_HOST;
> break;
> } else if (accessory ==
> TUSB320_REG8_ACCESSORY_CONNECTED_DBGUFP) {
> typec_mode = TYPEC_MODE_DEBUG;
> pwr_role = TYPEC_SINK;
> + usb_role = USB_ROLE_DEVICE;
> data_role = TYPEC_DEVICE;
> break;
> }
> @@ -339,6 +347,7 @@ static void tusb320_typec_irq_handler(struct tusb320_priv *priv, u8 reg9)
> fallthrough;
> default:
> typec_mode = TYPEC_MODE_USB2;
> + usb_role = USB_ROLE_NONE;
> pwr_role = TYPEC_SINK;
> data_role = TYPEC_DEVICE;
> break;
> @@ -348,6 +357,7 @@ static void tusb320_typec_irq_handler(struct tusb320_priv *priv, u8 reg9)
> typec_set_pwr_role(port, pwr_role);
> typec_set_data_role(port, data_role);
> typec_set_mode(port, typec_mode);
> + usb_role_switch_set_role(priv->role_sw, usb_role);
>
> mode = FIELD_GET(TUSB320_REG8_CURRENT_MODE_DETECT, reg8);
> if (mode == TUSB320_REG8_CURRENT_MODE_DETECT_DEF)
> @@ -472,10 +482,20 @@ static int tusb320_typec_probe(struct i2c_client *client,
> goto err_put;
> }
>
> + /* Find any optional USB role switch that needs reporting to */
> + priv->role_sw = fwnode_usb_role_switch_get(connector);
> + if (IS_ERR(priv->role_sw)) {
> + ret = PTR_ERR(priv->role_sw);
> + goto err_unreg;
> + }
> +
> priv->connector_fwnode = connector;
>
> return 0;
>
> +err_unreg:
> + typec_unregister_port(priv->port);
> +
> err_put:
> fwnode_handle_put(connector);
>
> @@ -484,6 +504,7 @@ static int tusb320_typec_probe(struct i2c_client *client,
>
> static void tusb320_typec_remove(struct tusb320_priv *priv)
> {
> + usb_role_switch_put(priv->role_sw);
> typec_unregister_port(priv->port);
> fwnode_handle_put(priv->connector_fwnode);
> }
> --
> 2.39.2
--
heikki
