diff options
Diffstat (limited to 'drivers/extcon/extcon_class.c')
| -rw-r--r-- | drivers/extcon/extcon_class.c | 439 |
1 files changed, 426 insertions, 13 deletions
diff --git a/drivers/extcon/extcon_class.c b/drivers/extcon/extcon_class.c index 83a088f1edc..403933bc3e9 100644 --- a/drivers/extcon/extcon_class.c +++ b/drivers/extcon/extcon_class.c @@ -31,6 +31,39 @@ #include <linux/extcon.h> #include <linux/slab.h> +/* + * extcon_cable_name suggests the standard cable names for commonly used + * cable types. + * + * However, please do not use extcon_cable_name directly for extcon_dev + * struct's supported_cable pointer unless your device really supports + * every single port-type of the following cable names. Please choose cable + * names that are actually used in your extcon device. + */ +const char *extcon_cable_name[] = { + [EXTCON_USB] = "USB", + [EXTCON_USB_HOST] = "USB-Host", + [EXTCON_TA] = "TA", + [EXTCON_FAST_CHARGER] = "Fast-charger", + [EXTCON_SLOW_CHARGER] = "Slow-charger", + [EXTCON_CHARGE_DOWNSTREAM] = "Charge-downstream", + [EXTCON_HDMI] = "HDMI", + [EXTCON_MHL] = "MHL", + [EXTCON_DVI] = "DVI", + [EXTCON_VGA] = "VGA", + [EXTCON_DOCK] = "Dock", + [EXTCON_LINE_IN] = "Line-in", + [EXTCON_LINE_OUT] = "Line-out", + [EXTCON_MIC_IN] = "Microphone", + [EXTCON_HEADPHONE_OUT] = "Headphone", + [EXTCON_SPDIF_IN] = "SPDIF-in", + [EXTCON_SPDIF_OUT] = "SPDIF-out", + [EXTCON_VIDEO_IN] = "Video-in", + [EXTCON_VIDEO_OUT] = "Video-out", + + NULL, +}; + struct class *extcon_class; #if defined(CONFIG_ANDROID) && !defined(CONFIG_ANDROID_SWITCH) static struct class_compat *switch_class; @@ -42,6 +75,7 @@ static DEFINE_MUTEX(extcon_dev_list_lock); static ssize_t state_show(struct device *dev, struct device_attribute *attr, char *buf) { + int i, count = 0; struct extcon_dev *edev = (struct extcon_dev *) dev_get_drvdata(dev); if (edev->print_state) { @@ -51,7 +85,39 @@ static ssize_t state_show(struct device *dev, struct device_attribute *attr, return ret; /* Use default if failed */ } - return sprintf(buf, "%u\n", edev->state); + + if (edev->max_supported == 0) + return sprintf(buf, "%u\n", edev->state); + + for (i = 0; i < SUPPORTED_CABLE_MAX; i++) { + if (!edev->supported_cable[i]) + break; + count += sprintf(buf + count, "%s=%d\n", + edev->supported_cable[i], + !!(edev->state & (1 << i))); + } + + return count; +} + +void extcon_set_state(struct extcon_dev *edev, u32 state); +static ssize_t state_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + u32 state; + ssize_t ret = 0; + struct extcon_dev *edev = (struct extcon_dev *) dev_get_drvdata(dev); + + ret = sscanf(buf, "0x%x", &state); + if (ret == 0) + ret = -EINVAL; + else + extcon_set_state(edev, state); + + if (ret < 0) + return ret; + + return count; } static ssize_t name_show(struct device *dev, struct device_attribute *attr, @@ -69,9 +135,52 @@ static ssize_t name_show(struct device *dev, struct device_attribute *attr, return sprintf(buf, "%s\n", dev_name(edev->dev)); } +static ssize_t cable_name_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct extcon_cable *cable = container_of(attr, struct extcon_cable, + attr_name); + + return sprintf(buf, "%s\n", + cable->edev->supported_cable[cable->cable_index]); +} + +static ssize_t cable_state_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct extcon_cable *cable = container_of(attr, struct extcon_cable, + attr_state); + + return sprintf(buf, "%d\n", + extcon_get_cable_state_(cable->edev, + cable->cable_index)); +} + +static ssize_t cable_state_store(struct device *dev, + struct device_attribute *attr, const char *buf, + size_t count) +{ + struct extcon_cable *cable = container_of(attr, struct extcon_cable, + attr_state); + int ret, state; + + ret = sscanf(buf, "%d", &state); + if (ret == 0) + ret = -EINVAL; + else + ret = extcon_set_cable_state_(cable->edev, cable->cable_index, + state); + + if (ret < 0) + return ret; + return count; +} + /** - * extcon_set_state() - Set the cable attach states of the extcon device. + * extcon_update_state() - Update the cable attach states of the extcon device + * only for the masked bits. * @edev: the extcon device + * @mask: the bit mask to designate updated bits. * @state: new cable attach status for @edev * * Changing the state sends uevent with environment variable containing @@ -79,10 +188,10 @@ static ssize_t name_show(struct device *dev, struct device_attribute *attr, * Tizen uses this format for extcon device to get events from ports. * Android uses this format as well. * - * Note that notifier provides the which bits are changes in the state - * variable with "val" to the callback. + * Note that the notifier provides which bits are changed in the state + * variable with the val parameter (second) to the callback. */ -void extcon_set_state(struct extcon_dev *edev, u32 state) +void extcon_update_state(struct extcon_dev *edev, u32 mask, u32 state) { char name_buf[120]; char state_buf[120]; @@ -90,15 +199,20 @@ void extcon_set_state(struct extcon_dev *edev, u32 state) char *envp[3]; int env_offset = 0; int length; - u32 old_state = edev->state; + unsigned long flags; - if (edev->state != state) { - edev->state = state; + spin_lock_irqsave(&edev->lock, flags); - raw_notifier_call_chain(&edev->nh, old_state ^ edev->state, - edev); + if (edev->state != ((edev->state & ~mask) | (state & mask))) { + u32 old_state = edev->state; - prop_buf = (char *)get_zeroed_page(GFP_KERNEL); + edev->state &= ~mask; + edev->state |= state & mask; + + raw_notifier_call_chain(&edev->nh, old_state, edev); + + /* This could be in interrupt handler */ + prop_buf = (char *)get_zeroed_page(GFP_ATOMIC); if (prop_buf) { length = name_show(edev->dev, NULL, prop_buf); if (length > 0) { @@ -117,17 +231,132 @@ void extcon_set_state(struct extcon_dev *edev, u32 state) envp[env_offset++] = state_buf; } envp[env_offset] = NULL; + /* Unlock early before uevent */ + spin_unlock_irqrestore(&edev->lock, flags); + kobject_uevent_env(&edev->dev->kobj, KOBJ_CHANGE, envp); free_page((unsigned long)prop_buf); } else { + /* Unlock early before uevent */ + spin_unlock_irqrestore(&edev->lock, flags); + dev_err(edev->dev, "out of memory in extcon_set_state\n"); kobject_uevent(&edev->dev->kobj, KOBJ_CHANGE); } + } else { + /* No changes */ + spin_unlock_irqrestore(&edev->lock, flags); } } +EXPORT_SYMBOL_GPL(extcon_update_state); + +/** + * extcon_set_state() - Set the cable attach states of the extcon device. + * @edev: the extcon device + * @state: new cable attach status for @edev + * + * Note that notifier provides which bits are changed in the state + * variable with the val parameter (second) to the callback. + */ +void extcon_set_state(struct extcon_dev *edev, u32 state) +{ + extcon_update_state(edev, 0xffffffff, state); +} EXPORT_SYMBOL_GPL(extcon_set_state); /** + * extcon_find_cable_index() - Get the cable index based on the cable name. + * @edev: the extcon device that has the cable. + * @cable_name: cable name to be searched. + * + * Note that accessing a cable state based on cable_index is faster than + * cable_name because using cable_name induces a loop with strncmp(). + * Thus, when get/set_cable_state is repeatedly used, using cable_index + * is recommended. + */ +int extcon_find_cable_index(struct extcon_dev *edev, const char *cable_name) +{ + int i; + + if (edev->supported_cable) { + for (i = 0; edev->supported_cable[i]; i++) { + if (!strncmp(edev->supported_cable[i], + cable_name, CABLE_NAME_MAX)) + return i; + } + } + + return -EINVAL; +} +EXPORT_SYMBOL_GPL(extcon_find_cable_index); + +/** + * extcon_get_cable_state_() - Get the status of a specific cable. + * @edev: the extcon device that has the cable. + * @index: cable index that can be retrieved by extcon_find_cable_index(). + */ +int extcon_get_cable_state_(struct extcon_dev *edev, int index) +{ + if (index < 0 || (edev->max_supported && edev->max_supported <= index)) + return -EINVAL; + + return !!(edev->state & (1 << index)); +} +EXPORT_SYMBOL_GPL(extcon_get_cable_state_); + +/** + * extcon_get_cable_state() - Get the status of a specific cable. + * @edev: the extcon device that has the cable. + * @cable_name: cable name. + * + * Note that this is slower than extcon_get_cable_state_. + */ +int extcon_get_cable_state(struct extcon_dev *edev, const char *cable_name) +{ + return extcon_get_cable_state_(edev, extcon_find_cable_index + (edev, cable_name)); +} +EXPORT_SYMBOL_GPL(extcon_get_cable_state); + +/** + * extcon_get_cable_state_() - Set the status of a specific cable. + * @edev: the extcon device that has the cable. + * @index: cable index that can be retrieved by extcon_find_cable_index(). + * @cable_state: the new cable status. The default semantics is + * true: attached / false: detached. + */ +int extcon_set_cable_state_(struct extcon_dev *edev, + int index, bool cable_state) +{ + u32 state; + + if (index < 0 || (edev->max_supported && edev->max_supported <= index)) + return -EINVAL; + + state = cable_state ? (1 << index) : 0; + extcon_update_state(edev, 1 << index, state); + return 0; +} +EXPORT_SYMBOL_GPL(extcon_set_cable_state_); + +/** + * extcon_get_cable_state() - Set the status of a specific cable. + * @edev: the extcon device that has the cable. + * @cable_name: cable name. + * @cable_state: the new cable status. The default semantics is + * true: attached / false: detached. + * + * Note that this is slower than extcon_set_cable_state_. + */ +int extcon_set_cable_state(struct extcon_dev *edev, + const char *cable_name, bool cable_state) +{ + return extcon_set_cable_state_(edev, extcon_find_cable_index + (edev, cable_name), cable_state); +} +EXPORT_SYMBOL_GPL(extcon_set_cable_state); + +/** * extcon_get_extcon_dev() - Get the extcon device instance from the name * @extcon_name: The extcon name provided with extcon_dev_register() */ @@ -147,11 +376,88 @@ out: } EXPORT_SYMBOL_GPL(extcon_get_extcon_dev); +static int _call_per_cable(struct notifier_block *nb, unsigned long val, + void *ptr) +{ + struct extcon_specific_cable_nb *obj = container_of(nb, + struct extcon_specific_cable_nb, internal_nb); + struct extcon_dev *edev = ptr; + + if ((val & (1 << obj->cable_index)) != + (edev->state & (1 << obj->cable_index))) { + obj->previous_value = val; + return obj->user_nb->notifier_call(obj->user_nb, val, ptr); + } + + return NOTIFY_OK; +} + +/** + * extcon_register_interest() - Register a notifier for a state change of a + * specific cable, not a entier set of cables of a + * extcon device. + * @obj: an empty extcon_specific_cable_nb object to be returned. + * @extcon_name: the name of extcon device. + * @cable_name: the target cable name. + * @nb: the notifier block to get notified. + * + * Provide an empty extcon_specific_cable_nb. extcon_register_interest() sets + * the struct for you. + * + * extcon_register_interest is a helper function for those who want to get + * notification for a single specific cable's status change. If a user wants + * to get notification for any changes of all cables of a extcon device, + * he/she should use the general extcon_register_notifier(). + * + * Note that the second parameter given to the callback of nb (val) is + * "old_state", not the current state. The current state can be retrieved + * by looking at the third pameter (edev pointer)'s state value. + */ +int extcon_register_interest(struct extcon_specific_cable_nb *obj, + const char *extcon_name, const char *cable_name, + struct notifier_block *nb) +{ + if (!obj || !extcon_name || !cable_name || !nb) + return -EINVAL; + + obj->edev = extcon_get_extcon_dev(extcon_name); + if (!obj->edev) + return -ENODEV; + + obj->cable_index = extcon_find_cable_index(obj->edev, cable_name); + if (obj->cable_index < 0) + return -ENODEV; + + obj->user_nb = nb; + + obj->internal_nb.notifier_call = _call_per_cable; + + return raw_notifier_chain_register(&obj->edev->nh, &obj->internal_nb); +} + +/** + * extcon_unregister_interest() - Unregister the notifier registered by + * extcon_register_interest(). + * @obj: the extcon_specific_cable_nb object returned by + * extcon_register_interest(). + */ +int extcon_unregister_interest(struct extcon_specific_cable_nb *obj) +{ + if (!obj) + return -EINVAL; + + return raw_notifier_chain_unregister(&obj->edev->nh, &obj->internal_nb); +} + /** * extcon_register_notifier() - Register a notifee to get notified by * any attach status changes from the extcon. * @edev: the extcon device. * @nb: a notifier block to be registered. + * + * Note that the second parameter given to the callback of nb (val) is + * "old_state", not the current state. The current state can be retrieved + * by looking at the third pameter (edev pointer)'s state value. */ int extcon_register_notifier(struct extcon_dev *edev, struct notifier_block *nb) @@ -173,8 +479,9 @@ int extcon_unregister_notifier(struct extcon_dev *edev, EXPORT_SYMBOL_GPL(extcon_unregister_notifier); static struct device_attribute extcon_attrs[] = { - __ATTR_RO(state), + __ATTR(state, S_IRUGO | S_IWUSR, state_show, state_store), __ATTR_RO(name), + __ATTR_NULL, }; static int create_extcon_class(void) @@ -202,6 +509,16 @@ static void extcon_cleanup(struct extcon_dev *edev, bool skip) mutex_unlock(&extcon_dev_list_lock); if (!skip && get_device(edev->dev)) { + int index; + + for (index = 0; index < edev->max_supported; index++) + kfree(edev->cables[index].attr_g.name); + + if (edev->max_supported) { + kfree(edev->extcon_dev_type.groups); + kfree(edev->cables); + } + device_unregister(edev->dev); put_device(edev->dev); } @@ -216,6 +533,10 @@ static void extcon_dev_release(struct device *dev) extcon_cleanup(edev, true); } +static void dummy_sysfs_dev_release(struct device *dev) +{ +} + /** * extcon_dev_register() - Register a new extcon device * @edev : the new extcon device (should be allocated before calling) @@ -228,7 +549,7 @@ static void extcon_dev_release(struct device *dev) */ int extcon_dev_register(struct extcon_dev *edev, struct device *dev) { - int ret; + int ret, index = 0; if (!extcon_class) { ret = create_extcon_class(); @@ -236,12 +557,93 @@ int extcon_dev_register(struct extcon_dev *edev, struct device *dev) return ret; } + if (edev->supported_cable) { + /* Get size of array */ + for (index = 0; edev->supported_cable[index]; index++) + ; + edev->max_supported = index; + } else { + edev->max_supported = 0; + } + + if (index > SUPPORTED_CABLE_MAX) { + dev_err(edev->dev, "extcon: maximum number of supported cables exceeded.\n"); + return -EINVAL; + } + edev->dev = kzalloc(sizeof(struct device), GFP_KERNEL); edev->dev->parent = dev; edev->dev->class = extcon_class; edev->dev->release = extcon_dev_release; dev_set_name(edev->dev, edev->name ? edev->name : dev_name(dev)); + + if (edev->max_supported) { + char buf[10]; + char *str; + struct extcon_cable *cable; + + edev->cables = kzalloc(sizeof(struct extcon_cable) * + edev->max_supported, GFP_KERNEL); + if (!edev->cables) { + ret = -ENOMEM; + goto err_sysfs_alloc; + } + for (index = 0; index < edev->max_supported; index++) { + cable = &edev->cables[index]; + + snprintf(buf, 10, "cable.%d", index); + str = kzalloc(sizeof(char) * (strlen(buf) + 1), + GFP_KERNEL); + if (!str) { + for (index--; index >= 0; index--) { + cable = &edev->cables[index]; + kfree(cable->attr_g.name); + } + ret = -ENOMEM; + + goto err_alloc_cables; + } + strcpy(str, buf); + + cable->edev = edev; + cable->cable_index = index; + cable->attrs[0] = &cable->attr_name.attr; + cable->attrs[1] = &cable->attr_state.attr; + cable->attrs[2] = NULL; + cable->attr_g.name = str; + cable->attr_g.attrs = cable->attrs; + + cable->attr_name.attr.name = "name"; + cable->attr_name.attr.mode = 0444; + cable->attr_name.show = cable_name_show; + + cable->attr_state.attr.name = "state"; + cable->attr_state.attr.mode = 0644; + cable->attr_state.show = cable_state_show; + cable->attr_state.store = cable_state_store; + } + } + + if (edev->max_supported) { + edev->extcon_dev_type.groups = + kzalloc(sizeof(struct attribute_group *) * + (edev->max_supported + 1), GFP_KERNEL); + if (!edev->extcon_dev_type.groups) { + ret = -ENOMEM; + goto err_alloc_groups; + } + + edev->extcon_dev_type.name = dev_name(edev->dev); + edev->extcon_dev_type.release = dummy_sysfs_dev_release; + + for (index = 0; index < edev->max_supported; index++) + edev->extcon_dev_type.groups[index] = + &edev->cables[index].attr_g; + + edev->dev->type = &edev->extcon_dev_type; + } + ret = device_register(edev->dev); if (ret) { put_device(edev->dev); @@ -253,6 +655,8 @@ int extcon_dev_register(struct extcon_dev *edev, struct device *dev) dev); #endif /* CONFIG_ANDROID && !defined(CONFIG_ANDROID_SWITCH) */ + spin_lock_init(&edev->lock); + RAW_INIT_NOTIFIER_HEAD(&edev->nh); dev_set_drvdata(edev->dev, edev); @@ -265,6 +669,15 @@ int extcon_dev_register(struct extcon_dev *edev, struct device *dev) return 0; err_dev: + if (edev->max_supported) + kfree(edev->extcon_dev_type.groups); +err_alloc_groups: + for (index = 0; index < edev->max_supported; index++) + kfree(edev->cables[index].attr_g.name); +err_alloc_cables: + if (edev->max_supported) + kfree(edev->cables); +err_sysfs_alloc: kfree(edev->dev); return ret; } |