path: root/drivers/usb/typec/class.c

// SPDX-License-Identifier: GPL-2.0
/*
 * USB Type-C Connector Class
 *
 * Copyright (C) 2017, Intel Corporation
 * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
 */

#include <linux/device.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/usb/typec.h>
#include <linux/usb/typec_mux.h>

struct typec_mode {
	int				index;
	u32				vdo;
	char				*desc;
	enum typec_port_type		roles;

	struct typec_altmode		*alt_mode;

	unsigned int			active:1;

	char				group_name[6];
	struct attribute_group		group;
	struct attribute		*attrs[5];
	struct device_attribute		vdo_attr;
	struct device_attribute		desc_attr;
	struct device_attribute		active_attr;
	struct device_attribute		roles_attr;
};

struct typec_altmode {
	struct device			dev;
	u16				svid;
	int				n_modes;
	struct typec_mode		modes[ALTMODE_MAX_MODES];
	const struct attribute_group	*mode_groups[ALTMODE_MAX_MODES];
};

struct typec_plug {
	struct device			dev;
	enum typec_plug_index		index;
};

struct typec_cable {
	struct device			dev;
	enum typec_plug_type		type;
	struct usb_pd_identity		*identity;
	unsigned int			active:1;
};

struct typec_partner {
	struct device			dev;
	unsigned int			usb_pd:1;
	struct usb_pd_identity		*identity;
	enum typec_accessory		accessory;
};

struct typec_port {
	unsigned int			id;
	struct device			dev;

	int				prefer_role;
	enum typec_data_role		data_role;
	enum typec_role			pwr_role;
	enum typec_role			vconn_role;
	enum typec_pwr_opmode		pwr_opmode;
	enum typec_port_type		port_type;
	struct mutex			port_type_lock;

	enum typec_orientation		orientation;
	struct typec_switch		*sw;
	struct typec_mux		*mux;

	const struct typec_capability	*cap;
};

#define to_typec_port(_dev_) container_of(_dev_, struct typec_port, dev)
#define to_typec_plug(_dev_) container_of(_dev_, struct typec_plug, dev)
#define to_typec_cable(_dev_) container_of(_dev_, struct typec_cable, dev)
#define to_typec_partner(_dev_) container_of(_dev_, struct typec_partner, dev)
#define to_altmode(_dev_) container_of(_dev_, struct typec_altmode, dev)

static const struct device_type typec_partner_dev_type;
static const struct device_type typec_cable_dev_type;
static const struct device_type typec_plug_dev_type;
static const struct device_type typec_port_dev_type;

#define is_typec_partner(_dev_) (_dev_->type == &typec_partner_dev_type)
#define is_typec_cable(_dev_) (_dev_->type == &typec_cable_dev_type)
#define is_typec_plug(_dev_) (_dev_->type == &typec_plug_dev_type)
#define is_typec_port(_dev_) (_dev_->type == &typec_port_dev_type)

static DEFINE_IDA(typec_index_ida);
static struct class *typec_class;

/* ------------------------------------------------------------------------- */
/* Common attributes */

static const char * const typec_accessory_modes[] = {
	[TYPEC_ACCESSORY_NONE]		= "none",
	[TYPEC_ACCESSORY_AUDIO]		= "analog_audio",
	[TYPEC_ACCESSORY_DEBUG]		= "debug",
};

static struct usb_pd_identity *get_pd_identity(struct device *dev)
{
	if (is_typec_partner(dev)) {
		struct typec_partner *partner = to_typec_partner(dev);

		return partner->identity;
	} else if (is_typec_cable(dev)) {
		struct typec_cable *cable = to_typec_cable(dev);

		return cable->identity;
	}
	return NULL;
}

static ssize_t id_header_show(struct device *dev, struct device_attribute *attr,
			      char *buf)
{
	struct usb_pd_identity *id = get_pd_identity(dev);

	return sprintf(buf, "0x%08x\n", id->id_header);
}
static DEVICE_ATTR_RO(id_header);

static ssize_t cert_stat_show(struct device *dev, struct device_attribute *attr,
			      char *buf)
{
	struct usb_pd_identity *id = get_pd_identity(dev);

	return sprintf(buf, "0x%08x\n", id->cert_stat);
}
static DEVICE_ATTR_RO(cert_stat);

static ssize_t product_show(struct device *dev, struct device_attribute *attr,
			    char *buf)
{
	struct usb_pd_identity *id = get_pd_identity(dev);

	return sprintf(buf, "0x%08x\n", id->product);
}
static DEVICE_ATTR_RO(product);

static struct attribute *usb_pd_id_attrs[] = {
	&dev_attr_id_header.attr,
	&dev_attr_cert_stat.attr,
	&dev_attr_product.attr,
	NULL
};

static const struct attribute_group usb_pd_id_group = {
	.name = "identity",
	.attrs = usb_pd_id_attrs,
};

static const struct attribute_group *usb_pd_id_groups[] = {
	&usb_pd_id_group,
	NULL,
};

static void typec_report_identity(struct device *dev)
{
	sysfs_notify(&dev->kobj, "identity", "id_header");
	sysfs_notify(&dev->kobj, "identity", "cert_stat");
	sysfs_notify(&dev->kobj, "identity", "product");
}

/* ------------------------------------------------------------------------- */
/* Alternate Modes */

/**
 * typec_altmode_update_active - Report Enter/Exit mode
 * @alt: Handle to the alternate mode
 * @mode: Mode index
 * @active: True when the mode has been entered
 *
 * If a partner or cable plug executes Enter/Exit Mode command successfully, the
 * drivers use this routine to report the updated state of the mode.
 */
void typec_altmode_update_active(struct typec_altmode *alt, int mode,
				 bool active)
{
	struct typec_mode *m = &alt->modes[mode];
	char dir[6];

	if (m->active == active)
		return;

	m->active = active;
	snprintf(dir, sizeof(dir), "mode%d", mode);
	sysfs_notify(&alt->dev.kobj, dir, "active");
	kobject_uevent(&alt->dev.kobj, KOBJ_CHANGE);
}
EXPORT_SYMBOL_GPL(typec_altmode_update_active);

/**
 * typec_altmode2port - Alternate Mode to USB Type-C port
 * @alt: The Alternate Mode
 *
 * Returns handle to the port that a cable plug or partner with @alt is
 * connected to.
 */
struct typec_port *typec_altmode2port(struct typec_altmode *alt)
{
	if (is_typec_plug(alt->dev.parent))
		return to_typec_port(alt->dev.parent->parent->parent);
	if (is_typec_partner(alt->dev.parent))
		return to_typec_port(alt->dev.parent->parent);
	if (is_typec_port(alt->dev.parent))
		return to_typec_port(alt->dev.parent);

	return NULL;
}
EXPORT_SYMBOL_GPL(typec_altmode2port);

static ssize_t
typec_altmode_vdo_show(struct device *dev, struct device_attribute *attr,
		       char *buf)
{
	struct typec_mode *mode = container_of(attr, struct typec_mode,
					       vdo_attr);

	return sprintf(buf, "0x%08x\n", mode->vdo);
}

static ssize_t
typec_altmode_desc_show(struct device *dev, struct device_attribute *attr,
			char *buf)
{
	struct typec_mode *mode = container_of(attr, struct typec_mode,
					       desc_attr);

	return sprintf(buf, "%s\n", mode->desc ? mode->desc : "");
}

static ssize_t
typec_altmode_active_show(struct device *dev, struct device_attribute *attr,
			  char *buf)
{
	struct typec_mode *mode = container_of(attr, struct typec_mode,
					       active_attr);

	return sprintf(buf, "%s\n", mode->active ? "yes" : "no");
}

static ssize_t
typec_altmode_active_store(struct device *dev, struct device_attribute *attr,
			   const char *buf, size_t size)
{
	struct typec_mode *mode = container_of(attr, struct typec_mode,
					       active_attr);
	struct typec_port *port = typec_altmode2port(mode->alt_mode);
	bool activate;
	int ret;

	if (!port->cap->activate_mode)
		return -EOPNOTSUPP;

	ret = kstrtobool(buf, &activate);
	if (ret)
		return ret;

	ret = port->cap->activate_mode(port->cap, mode->index, activate);
	if (ret)
		return ret;

	return size;
}

static ssize_t
typec_altmode_roles_show(struct device *dev, struct device_attribute *attr,
			 char *buf)
{
	struct typec_mode *mode = container_of(attr, struct typec_mode,
					       roles_attr);
	ssize_t ret;

	switch (mode->roles) {
	case TYPEC_PORT_SRC:
		ret = sprintf(buf, "source\n");
		break;
	case TYPEC_PORT_SNK:
		ret = sprintf(buf, "sink\n");
		break;
	case TYPEC_PORT_DRP:
	default:
		ret = sprintf(buf, "source sink\n");
		break;
	}
	return ret;
}

static void typec_init_modes(struct typec_altmode *alt,
			     const struct typec_mode_desc *desc, bool is_port)
{
	int i;

	for (i = 0; i < alt->n_modes; i++, desc++) {
		struct typec_mode *mode = &alt->modes[i];

		/* Not considering the human readable description critical */
		mode->desc = kstrdup(desc->desc, GFP_KERNEL);
		if (desc->desc && !mode->desc)
			dev_err(&