diff options
Diffstat (limited to 'drivers/usb/phy/phy.c')
| -rw-r--r-- | drivers/usb/phy/phy.c | 770 |
1 files changed, 770 insertions, 0 deletions
diff --git a/drivers/usb/phy/phy.c b/drivers/usb/phy/phy.c new file mode 100644 index 000000000..1b24492bb --- /dev/null +++ b/drivers/usb/phy/phy.c @@ -0,0 +1,770 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * phy.c -- USB phy handling + * + * Copyright (C) 2004-2013 Texas Instruments + */ +#include <linux/kernel.h> +#include <linux/export.h> +#include <linux/err.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/of.h> + +#include <linux/usb/phy.h> + +/* Default current range by charger type. */ +#define DEFAULT_SDP_CUR_MIN 2 +#define DEFAULT_SDP_CUR_MAX 500 +#define DEFAULT_SDP_CUR_MIN_SS 150 +#define DEFAULT_SDP_CUR_MAX_SS 900 +#define DEFAULT_DCP_CUR_MIN 500 +#define DEFAULT_DCP_CUR_MAX 5000 +#define DEFAULT_CDP_CUR_MIN 1500 +#define DEFAULT_CDP_CUR_MAX 5000 +#define DEFAULT_ACA_CUR_MIN 1500 +#define DEFAULT_ACA_CUR_MAX 5000 + +static LIST_HEAD(phy_list); +static DEFINE_SPINLOCK(phy_lock); + +struct phy_devm { + struct usb_phy *phy; + struct notifier_block *nb; +}; + +static const char *const usb_chger_type[] = { + [UNKNOWN_TYPE] = "USB_CHARGER_UNKNOWN_TYPE", + [SDP_TYPE] = "USB_CHARGER_SDP_TYPE", + [CDP_TYPE] = "USB_CHARGER_CDP_TYPE", + [DCP_TYPE] = "USB_CHARGER_DCP_TYPE", + [ACA_TYPE] = "USB_CHARGER_ACA_TYPE", +}; + +static const char *const usb_chger_state[] = { + [USB_CHARGER_DEFAULT] = "USB_CHARGER_DEFAULT", + [USB_CHARGER_PRESENT] = "USB_CHARGER_PRESENT", + [USB_CHARGER_ABSENT] = "USB_CHARGER_ABSENT", +}; + +static struct usb_phy *__usb_find_phy(struct list_head *list, + enum usb_phy_type type) +{ + struct usb_phy *phy = NULL; + + list_for_each_entry(phy, list, head) { + if (phy->type != type) + continue; + + return phy; + } + + return ERR_PTR(-ENODEV); +} + +static struct usb_phy *__of_usb_find_phy(struct device_node *node) +{ + struct usb_phy *phy; + + if (!of_device_is_available(node)) + return ERR_PTR(-ENODEV); + + list_for_each_entry(phy, &phy_list, head) { + if (node != phy->dev->of_node) + continue; + + return phy; + } + + return ERR_PTR(-EPROBE_DEFER); +} + +static struct usb_phy *__device_to_usb_phy(struct device *dev) +{ + struct usb_phy *usb_phy; + + list_for_each_entry(usb_phy, &phy_list, head) { + if (usb_phy->dev == dev) + return usb_phy; + } + + return NULL; +} + +static void usb_phy_set_default_current(struct usb_phy *usb_phy) +{ + usb_phy->chg_cur.sdp_min = DEFAULT_SDP_CUR_MIN; + usb_phy->chg_cur.sdp_max = DEFAULT_SDP_CUR_MAX; + usb_phy->chg_cur.dcp_min = DEFAULT_DCP_CUR_MIN; + usb_phy->chg_cur.dcp_max = DEFAULT_DCP_CUR_MAX; + usb_phy->chg_cur.cdp_min = DEFAULT_CDP_CUR_MIN; + usb_phy->chg_cur.cdp_max = DEFAULT_CDP_CUR_MAX; + usb_phy->chg_cur.aca_min = DEFAULT_ACA_CUR_MIN; + usb_phy->chg_cur.aca_max = DEFAULT_ACA_CUR_MAX; +} + +/** + * usb_phy_notify_charger_work - notify the USB charger state + * @work: the charger work to notify the USB charger state + * + * This work can be issued when USB charger state has been changed or + * USB charger current has been changed, then we can notify the current + * what can be drawn to power user and the charger state to userspace. + * + * If we get the charger type from extcon subsystem, we can notify the + * charger state to power user automatically by usb_phy_get_charger_type() + * issuing from extcon subsystem. + * + * If we get the charger type from ->charger_detect() instead of extcon + * subsystem, the usb phy driver should issue usb_phy_set_charger_state() + * to set charger state when the charger state has been changed. + */ +static void usb_phy_notify_charger_work(struct work_struct *work) +{ + struct usb_phy *usb_phy = container_of(work, struct usb_phy, chg_work); + unsigned int min, max; + + switch (usb_phy->chg_state) { + case USB_CHARGER_PRESENT: + usb_phy_get_charger_current(usb_phy, &min, &max); + + atomic_notifier_call_chain(&usb_phy->notifier, max, usb_phy); + break; + case USB_CHARGER_ABSENT: + usb_phy_set_default_current(usb_phy); + + atomic_notifier_call_chain(&usb_phy->notifier, 0, usb_phy); + break; + default: + dev_warn(usb_phy->dev, "Unknown USB charger state: %d\n", + usb_phy->chg_state); + return; + } + + kobject_uevent(&usb_phy->dev->kobj, KOBJ_CHANGE); +} + +static int usb_phy_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + struct usb_phy *usb_phy; + char uchger_state[50] = { 0 }; + char uchger_type[50] = { 0 }; + unsigned long flags; + + spin_lock_irqsave(&phy_lock, flags); + usb_phy = __device_to_usb_phy(dev); + spin_unlock_irqrestore(&phy_lock, flags); + + if (!usb_phy) + return -ENODEV; + + snprintf(uchger_state, ARRAY_SIZE(uchger_state), + "USB_CHARGER_STATE=%s", usb_chger_state[usb_phy->chg_state]); + + snprintf(uchger_type, ARRAY_SIZE(uchger_type), + "USB_CHARGER_TYPE=%s", usb_chger_type[usb_phy->chg_type]); + + if (add_uevent_var(env, uchger_state)) + return -ENOMEM; + + if (add_uevent_var(env, uchger_type)) + return -ENOMEM; + + return 0; +} + +static void __usb_phy_get_charger_type(struct usb_phy *usb_phy) +{ + if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_SDP) > 0) { + usb_phy->chg_type = SDP_TYPE; + usb_phy->chg_state = USB_CHARGER_PRESENT; + } else if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_CDP) > 0) { + usb_phy->chg_type = CDP_TYPE; + usb_phy->chg_state = USB_CHARGER_PRESENT; + } else if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_DCP) > 0) { + usb_phy->chg_type = DCP_TYPE; + usb_phy->chg_state = USB_CHARGER_PRESENT; + } else if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_ACA) > 0) { + usb_phy->chg_type = ACA_TYPE; + usb_phy->chg_state = USB_CHARGER_PRESENT; + } else { + usb_phy->chg_type = UNKNOWN_TYPE; + usb_phy->chg_state = USB_CHARGER_ABSENT; + } + + schedule_work(&usb_phy->chg_work); +} + +/** + * usb_phy_get_charger_type - get charger type from extcon subsystem + * @nb: the notifier block to determine charger type + * @state: the cable state + * @data: private data + * + * Determin the charger type from extcon subsystem which also means the + * charger state has been chaned, then we should notify this event. + */ +static int usb_phy_get_charger_type(struct notifier_block *nb, + unsigned long state, void *data) +{ + struct usb_phy *usb_phy = container_of(nb, struct usb_phy, type_nb); + + __usb_phy_get_charger_type(usb_phy); + return NOTIFY_OK; +} + +/** + * usb_phy_set_charger_current - set the USB charger current + * @usb_phy: the USB phy to be used + * @mA: the current need to be set + * + * Usually we only change the charger default current when USB finished the + * enumeration as one SDP charger. As one SDP charger, usb_phy_set_power() + * will issue this function to change charger current when after setting USB + * configuration, or suspend/resume USB. For other type charger, we should + * use the default charger current and we do not suggest to issue this function + * to change the charger current. + * + * When USB charger current has been changed, we need to notify the power users. + */ +void usb_phy_set_charger_current(struct usb_phy *usb_phy, unsigned int mA) +{ + switch (usb_phy->chg_type) { + case SDP_TYPE: + if (usb_phy->chg_cur.sdp_max == mA) + return; + + usb_phy->chg_cur.sdp_max = (mA > DEFAULT_SDP_CUR_MAX_SS) ? + DEFAULT_SDP_CUR_MAX_SS : mA; + break; + case DCP_TYPE: + if (usb_phy->chg_cur.dcp_max == mA) + return; + + usb_phy->chg_cur.dcp_max = (mA > DEFAULT_DCP_CUR_MAX) ? + DEFAULT_DCP_CUR_MAX : mA; + break; + case CDP_TYPE: + if (usb_phy->chg_cur.cdp_max == mA) + return; + + usb_phy->chg_cur.cdp_max = (mA > DEFAULT_CDP_CUR_MAX) ? + DEFAULT_CDP_CUR_MAX : mA; + break; + case ACA_TYPE: + if (usb_phy->chg_cur.aca_max == mA) + return; + + usb_phy->chg_cur.aca_max = (mA > DEFAULT_ACA_CUR_MAX) ? + DEFAULT_ACA_CUR_MAX : mA; + break; + default: + return; + } + + schedule_work(&usb_phy->chg_work); +} +EXPORT_SYMBOL_GPL(usb_phy_set_charger_current); + +/** + * usb_phy_get_charger_current - get the USB charger current + * @usb_phy: the USB phy to be used + * @min: the minimum current + * @max: the maximum current + * + * Usually we will notify the maximum current to power user, but for some + * special case, power user also need the minimum current value. Then the + * power user can issue this function to get the suitable current. + */ +void usb_phy_get_charger_current(struct usb_phy *usb_phy, + unsigned int *min, unsigned int *max) +{ + switch (usb_phy->chg_type) { + case SDP_TYPE: + *min = usb_phy->chg_cur.sdp_min; + *max = usb_phy->chg_cur.sdp_max; + break; + case DCP_TYPE: + *min = usb_phy->chg_cur.dcp_min; + *max = usb_phy->chg_cur.dcp_max; + break; + case CDP_TYPE: + *min = usb_phy->chg_cur.cdp_min; + *max = usb_phy->chg_cur.cdp_max; + break; + case ACA_TYPE: + *min = usb_phy->chg_cur.aca_min; + *max = usb_phy->chg_cur.aca_max; + break; + default: + *min = 0; + *max = 0; + break; + } +} +EXPORT_SYMBOL_GPL(usb_phy_get_charger_current); + +/** + * usb_phy_set_charger_state - set the USB charger state + * @usb_phy: the USB phy to be used + * @state: the new state need to be set for charger + * + * The usb phy driver can issue this function when the usb phy driver + * detected the charger state has been changed, in this case the charger + * type should be get from ->charger_detect(). + */ +void usb_phy_set_charger_state(struct usb_phy *usb_phy, + enum usb_charger_state state) +{ + if (usb_phy->chg_state == state || !usb_phy->charger_detect) + return; + + usb_phy->chg_state = state; + if (usb_phy->chg_state == USB_CHARGER_PRESENT) + usb_phy->chg_type = usb_phy->charger_detect(usb_phy); + else + usb_phy->chg_type = UNKNOWN_TYPE; + + schedule_work(&usb_phy->chg_work); +} +EXPORT_SYMBOL_GPL(usb_phy_set_charger_state); + +static void devm_usb_phy_release(struct device *dev, void *res) +{ + struct usb_phy *phy = *(struct usb_phy **)res; + + usb_put_phy(phy); +} + +static void devm_usb_phy_release2(struct device *dev, void *_res) +{ + struct phy_devm *res = _res; + + if (res->nb) + usb_unregister_notifier(res->phy, res->nb); + usb_put_phy(res->phy); +} + +static int devm_usb_phy_match(struct device *dev, void *res, void *match_data) +{ + struct usb_phy **phy = res; + + return *phy == match_data; +} + +static void usb_charger_init(struct usb_phy *usb_phy) +{ + usb_phy->chg_type = UNKNOWN_TYPE; + usb_phy->chg_state = USB_CHARGER_DEFAULT; + usb_phy_set_default_current(usb_phy); + INIT_WORK(&usb_phy->chg_work, usb_phy_notify_charger_work); +} + +static int usb_add_extcon(struct usb_phy *x) +{ + int ret; + + if (of_property_read_bool(x->dev->of_node, "extcon")) { + x->edev = extcon_get_edev_by_phandle(x->dev, 0); + if (IS_ERR(x->edev)) + return PTR_ERR(x->edev); + + x->id_edev = extcon_get_edev_by_phandle(x->dev, 1); + if (IS_ERR(x->id_edev)) { + x->id_edev = NULL; + dev_info(x->dev, "No separate ID extcon device\n"); + } + + if (x->vbus_nb.notifier_call) { + ret = devm_extcon_register_notifier(x->dev, x->edev, + EXTCON_USB, + &x->vbus_nb); + if (ret < 0) { + dev_err(x->dev, + "register VBUS notifier failed\n"); + return ret; + } + } else { + x->type_nb.notifier_call = usb_phy_get_charger_type; + + ret = devm_extcon_register_notifier(x->dev, x->edev, + EXTCON_CHG_USB_SDP, + &x->type_nb); + if (ret) { + dev_err(x->dev, + "register extcon USB SDP failed.\n"); + return ret; + } + + ret = devm_extcon_register_notifier(x->dev, x->edev, + EXTCON_CHG_USB_CDP, + &x->type_nb); + if (ret) { + dev_err(x->dev, + "register extcon USB CDP failed.\n"); + return ret; + } + + ret = devm_extcon_register_notifier(x->dev, x->edev, + EXTCON_CHG_USB_DCP, + &x->type_nb); + if (ret) { + dev_err(x->dev, + "register extcon USB DCP failed.\n"); + return ret; + } + + ret = devm_extcon_register_notifier(x->dev, x->edev, + EXTCON_CHG_USB_ACA, + &x->type_nb); + if (ret) { + dev_err(x->dev, + "register extcon USB ACA failed.\n"); + return ret; + } + } + + if (x->id_nb.notifier_call) { + struct extcon_dev *id_ext; + + if (x->id_edev) + id_ext = x->id_edev; + else + id_ext = x->edev; + + ret = devm_extcon_register_notifier(x->dev, id_ext, + EXTCON_USB_HOST, + &x->id_nb); + if (ret < 0) { + dev_err(x->dev, + "register ID notifier failed\n"); + return ret; + } + } + } + + if (x->type_nb.notifier_call) + __usb_phy_get_charger_type(x); + + return 0; +} + +/** + * devm_usb_get_phy - find the USB PHY + * @dev: device that requests this phy + * @type: the type of the phy the controller requires + * + * Gets the phy using usb_get_phy(), and associates a device with it using + * devres. On driver detach, release function is invoked on the devres data, + * then, devres data is freed. + * + * For use by USB host and peripheral drivers. + */ +struct usb_phy *devm_usb_get_phy(struct device *dev, enum usb_phy_type type) +{ + struct usb_phy **ptr, *phy; + + ptr = devres_alloc(devm_usb_phy_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + phy = usb_get_phy(type); + if (!IS_ERR(phy)) { + *ptr = phy; + devres_add(dev, ptr); + } else + devres_free(ptr); + + return phy; +} +EXPORT_SYMBOL_GPL(devm_usb_get_phy); + +/** + * usb_get_phy - find the USB PHY + * @type: the type of the phy the controller requires + * + * Returns the phy driver, after getting a refcount to it; or + * -ENODEV if there is no such phy. The caller is responsible for + * calling usb_put_phy() to release that count. + * + * For use by USB host and peripheral drivers. + */ +struct usb_phy *usb_get_phy(enum usb_phy_type type) +{ + struct usb_phy *phy = NULL; + unsigned long flags; + + spin_lock_irqsave(&phy_lock, flags); + + phy = __usb_find_phy(&phy_list, type); + if (IS_ERR(phy) || !try_module_get(phy->dev->driver->owner)) { + pr_debug("PHY: unable to find transceiver of type %s\n", + usb_phy_type_string(type)); + if (!IS_ERR(phy)) + phy = ERR_PTR(-ENODEV); + + goto err0; + } + + get_device(phy->dev); + +err0: + spin_unlock_irqrestore(&phy_lock, flags); + + return phy; +} +EXPORT_SYMBOL_GPL(usb_get_phy); + +/** + * devm_usb_get_phy_by_node - find the USB PHY by device_node + * @dev: device that requests this phy + * @node: the device_node for the phy device. + * @nb: a notifier_block to register with the phy. + * + * Returns the phy driver associated with the given device_node, + * after getting a refcount to it, -ENODEV if there is no such phy or + * -EPROBE_DEFER if the device is not yet loaded. While at that, it + * also associates the device with + * the phy using devres. On driver detach, release function is invoked + * on the devres data, then, devres data is freed. + * + * For use by peripheral drivers for devices related to a phy, + * such as a charger. + */ +struct usb_phy *devm_usb_get_phy_by_node(struct device *dev, + struct device_node *node, + struct notifier_block *nb) +{ + struct usb_phy *phy = ERR_PTR(-ENOMEM); + struct phy_devm *ptr; + unsigned long flags; + + ptr = devres_alloc(devm_usb_phy_release2, sizeof(*ptr), GFP_KERNEL); + if (!ptr) { + dev_dbg(dev, "failed to allocate memory for devres\n"); + goto err0; + } + + spin_lock_irqsave(&phy_lock, flags); + + phy = __of_usb_find_phy(node); + if (IS_ERR(phy)) { + devres_free(ptr); + goto err1; + } + + if (!try_module_get(phy->dev->driver->owner)) { + phy = ERR_PTR(-ENODEV); + devres_free(ptr); + goto err1; + } + if (nb) + usb_register_notifier(phy, nb); + ptr->phy = phy; + ptr->nb = nb; + devres_add(dev, ptr); + + get_device(phy->dev); + +err1: + spin_unlock_irqrestore(&phy_lock, flags); + +err0: + + return phy; +} +EXPORT_SYMBOL_GPL(devm_usb_get_phy_by_node); + +/** + * devm_usb_get_phy_by_phandle - find the USB PHY by phandle + * @dev: device that requests this phy + * @phandle: name of the property holding the phy phandle value + * @index: the index of the phy + * + * Returns the phy driver associated with the given phandle value, + * after getting a refcount to it, -ENODEV if there is no such phy or + * -EPROBE_DEFER if there is a phandle to the phy, but the device is + * not yet loaded. While at that, it also associates the device with + * the phy using devres. On driver detach, release function is invoked + * on the devres data, then, devres data is freed. + * + * For use by USB host and peripheral drivers. + */ +struct usb_phy *devm_usb_get_phy_by_phandle(struct device *dev, + const char *phandle, u8 index) +{ + struct device_node *node; + struct usb_phy *phy; + + if (!dev->of_node) { + dev_dbg(dev, "device does not have a device node entry\n"); + return ERR_PTR(-EINVAL); + } + + node = of_parse_phandle(dev->of_node, phandle, index); + if (!node) { + dev_dbg(dev, "failed to get %s phandle in %pOF node\n", phandle, + dev->of_node); + return ERR_PTR(-ENODEV); + } + phy = devm_usb_get_phy_by_node(dev, node, NULL); + of_node_put(node); + return phy; +} +EXPORT_SYMBOL_GPL(devm_usb_get_phy_by_phandle); + +/** + * devm_usb_put_phy - release the USB PHY + * @dev: device that wants to release this phy + * @phy: the phy returned by devm_usb_get_phy() + * + * destroys the devres associated with this phy and invokes usb_put_phy + * to release the phy. + * + * For use by USB host and peripheral drivers. + */ +void devm_usb_put_phy(struct device *dev, struct usb_phy *phy) +{ + int r; + + r = devres_destroy(dev, devm_usb_phy_release, devm_usb_phy_match, phy); + dev_WARN_ONCE(dev, r, "couldn't find PHY resource\n"); +} +EXPORT_SYMBOL_GPL(devm_usb_put_phy); + +/** + * usb_put_phy - release the USB PHY + * @x: the phy returned by usb_get_phy() + * + * Releases a refcount the caller received from usb_get_phy(). + * + * For use by USB host and peripheral drivers. + */ +void usb_put_phy(struct usb_phy *x) +{ + if (x) { + struct module *owner = x->dev->driver->owner; + + put_device(x->dev); + module_put(owner); + } +} +EXPORT_SYMBOL_GPL(usb_put_phy); + +/** + * usb_add_phy: declare the USB PHY + * @x: the USB phy to be used; or NULL + * @type: the type of this PHY + * + * This call is exclusively for use by phy drivers, which + * coordinate the activities of drivers for host and peripheral + * controllers, and in some cases for VBUS current regulation. + */ +int usb_add_phy(struct usb_phy *x, enum usb_phy_type type) +{ + int ret = 0; + unsigned long flags; + struct usb_phy *phy; + + if (x->type != USB_PHY_TYPE_UNDEFINED) { + dev_err(x->dev, "not accepting initialized PHY %s\n", x->label); + return -EINVAL; + } + + usb_charger_init(x); + ret = usb_add_extcon(x); + if (ret) + return ret; + + ATOMIC_INIT_NOTIFIER_HEAD(&x->notifier); + + spin_lock_irqsave(&phy_lock, flags); + + list_for_each_entry(phy, &phy_list, head) { + if (phy->type == type) { + ret = -EBUSY; + dev_err(x->dev, "transceiver type %s already exists\n", + usb_phy_type_string(type)); + goto out; + } + } + + x->type = type; + list_add_tail(&x->head, &phy_list); + +out: + spin_unlock_irqrestore(&phy_lock, flags); + return ret; +} +EXPORT_SYMBOL_GPL(usb_add_phy); + +static struct device_type usb_phy_dev_type = { + .name = "usb_phy", + .uevent = usb_phy_uevent, +}; + +/** + * usb_add_phy_dev - declare the USB PHY + * @x: the USB phy to be used; or NULL + * + * This call is exclusively for use by phy drivers, which + * coordinate the activities of drivers for host and peripheral + * controllers, and in some cases for VBUS current regulation. + */ +int usb_add_phy_dev(struct usb_phy *x) +{ + unsigned long flags; + int ret; + + if (!x->dev) { + dev_err(x->dev, "no device provided for PHY\n"); + return -EINVAL; + } + + usb_charger_init(x); + ret = usb_add_extcon(x); + if (ret) + return ret; + + x->dev->type = &usb_phy_dev_type; + + ATOMIC_INIT_NOTIFIER_HEAD(&x->notifier); + + spin_lock_irqsave(&phy_lock, flags); + list_add_tail(&x->head, &phy_list); + spin_unlock_irqrestore(&phy_lock, flags); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_add_phy_dev); + +/** + * usb_remove_phy - remove the OTG PHY + * @x: the USB OTG PHY to be removed; + * + * This reverts the effects of usb_add_phy + */ +void usb_remove_phy(struct usb_phy *x) +{ + unsigned long flags; + + spin_lock_irqsave(&phy_lock, flags); + if (x) + list_del(&x->head); + spin_unlock_irqrestore(&phy_lock, flags); +} +EXPORT_SYMBOL_GPL(usb_remove_phy); + +/** + * usb_phy_set_event - set event to phy event + * @x: the phy returned by usb_get_phy(); + * @event: event to set + * + * This sets event to phy event + */ +void usb_phy_set_event(struct usb_phy *x, unsigned long event) +{ + x->last_event = event; +} +EXPORT_SYMBOL_GPL(usb_phy_set_event); |