diff options
Diffstat (limited to 'drivers/extcon')
| -rw-r--r-- | drivers/extcon/extcon.c | 210 |
1 files changed, 135 insertions, 75 deletions
diff --git a/drivers/extcon/extcon.c b/drivers/extcon/extcon.c index d66adfd21159..8fde4befaa51 100644 --- a/drivers/extcon/extcon.c +++ b/drivers/extcon/extcon.c @@ -279,14 +279,11 @@ static bool is_extcon_attached(struct extcon_dev *edev, unsigned int index) return !!(edev->state & BIT(index)); } -static bool is_extcon_changed(u32 prev, u32 new, int idx, bool *attached) +static bool is_extcon_changed(struct extcon_dev *edev, int index, + bool new_state) { - if (((prev >> idx) & 0x1) != ((new >> idx) & 0x1)) { - *attached = ((new >> idx) & 0x1) ? true : false; - return true; - } - - return false; + int state = !!(edev->state & BIT(index)); + return (state != new_state); } static bool is_extcon_property_supported(unsigned int id, unsigned int prop) @@ -402,21 +399,13 @@ static ssize_t cable_state_show(struct device *dev, } /** - * 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 - * the name of extcon device (envp[0]) and the state output (envp[1]). - * Tizen uses this format for extcon device to get events from ports. - * Android uses this format as well. + * extcon_sync() - Synchronize the states for both the attached/detached + * @edev: the extcon device that has the cable. * - * Note that the notifier provides which bits are changed in the state - * variable with the val parameter (second) to the callback. + * This function send a notification to synchronize the all states of a + * specific external connector */ -static int extcon_update_state(struct extcon_dev *edev, u32 mask, u32 state) +int extcon_sync(struct extcon_dev *edev, unsigned int id) { char name_buf[120]; char state_buf[120]; @@ -425,73 +414,58 @@ static int extcon_update_state(struct extcon_dev *edev, u32 mask, u32 state) int env_offset = 0; int length; int index; + int state; unsigned long flags; - bool attached; if (!edev) return -EINVAL; + index = find_cable_index_by_id(edev, id); + if (index < 0) + return index; + spin_lock_irqsave(&edev->lock, flags); - if (edev->state != ((edev->state & ~mask) | (state & mask))) { - u32 old_state; + state = !!(edev->state & BIT(index)); + raw_notifier_call_chain(&edev->nh[index], state, edev); - if (check_mutually_exclusive(edev, (edev->state & ~mask) | - (state & mask))) { - spin_unlock_irqrestore(&edev->lock, flags); - return -EPERM; - } + /* This could be in interrupt handler */ + prop_buf = (char *)get_zeroed_page(GFP_ATOMIC); + if (!prop_buf) { + /* Unlock early before uevent */ + spin_unlock_irqrestore(&edev->lock, flags); - old_state = edev->state; - edev->state &= ~mask; - edev->state |= state & mask; + dev_err(&edev->dev, "out of memory in extcon_set_state\n"); + kobject_uevent(&edev->dev.kobj, KOBJ_CHANGE); - for (index = 0; index < edev->max_supported; index++) { - if (is_extcon_changed(old_state, edev->state, index, - &attached)) - raw_notifier_call_chain(&edev->nh[index], - attached, 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) { - if (prop_buf[length - 1] == '\n') - prop_buf[length - 1] = 0; - snprintf(name_buf, sizeof(name_buf), - "NAME=%s", prop_buf); - envp[env_offset++] = name_buf; - } - length = state_show(&edev->dev, NULL, prop_buf); - if (length > 0) { - if (prop_buf[length - 1] == '\n') - prop_buf[length - 1] = 0; - snprintf(state_buf, sizeof(state_buf), - "STATE=%s", prop_buf); - envp[env_offset++] = state_buf; - } - envp[env_offset] = NULL; - /* Unlock early before uevent */ - spin_unlock_irqrestore(&edev->lock, flags); + return 0; + } - 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); + length = name_show(&edev->dev, NULL, prop_buf); + if (length > 0) { + if (prop_buf[length - 1] == '\n') + prop_buf[length - 1] = 0; + snprintf(name_buf, sizeof(name_buf), "NAME=%s", prop_buf); + envp[env_offset++] = name_buf; + } - 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); + length = state_show(&edev->dev, NULL, prop_buf); + if (length > 0) { + if (prop_buf[length - 1] == '\n') + prop_buf[length - 1] = 0; + snprintf(state_buf, sizeof(state_buf), "STATE=%s", prop_buf); + 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); return 0; } +EXPORT_SYMBOL_GPL(extcon_sync); /** * extcon_get_state() - Get the state of a external connector. @@ -520,17 +494,22 @@ EXPORT_SYMBOL_GPL(extcon_get_state); /** * extcon_set_state() - Set the state of a external connector. + * without a notification. * @edev: the extcon device that has the cable. * @id: the unique id of each external connector * in extcon enumeration. * @state: the new cable status. The default semantics is * true: attached / false: detached. + * + * This function only set the state of a external connector without + * a notification. To synchronize the data of a external connector, + * use extcon_set_state_sync() and extcon_sync(). */ int extcon_set_state(struct extcon_dev *edev, unsigned int id, bool cable_state) { - u32 state; - int index; + unsigned long flags; + int index, ret = 0; if (!edev) return -EINVAL; @@ -539,6 +518,18 @@ int extcon_set_state(struct extcon_dev *edev, unsigned int id, if (index < 0) return index; + spin_lock_irqsave(&edev->lock, flags); + + /* Check whether the external connector's state is changed. */ + if (!is_extcon_changed(edev, index, cable_state)) + goto out; + + if (check_mutually_exclusive(edev, + (edev->state & ~BIT(index)) | (cable_state & BIT(index)))) { + ret = -EPERM; + goto out; + } + /* * Initialize the value of extcon property before setting * the detached state for an external connector. @@ -546,12 +537,56 @@ int extcon_set_state(struct extcon_dev *edev, unsigned int id, if (!cable_state) init_property(edev, id, index); - state = cable_state ? (1 << index) : 0; - return extcon_update_state(edev, 1 << index, state); + /* Update the state for a external connector. */ + if (cable_state) + edev->state |= BIT(index); + else + edev->state &= ~(BIT(index)); +out: + spin_unlock_irqrestore(&edev->lock, flags); + + return ret; } EXPORT_SYMBOL_GPL(extcon_set_state); /** + * extcon_set_state_sync() - Set the state of a external connector + * with a notification. + * @edev: the extcon device that has the cable. + * @id: the unique id of each external connector + * in extcon enumeration. + * @state: the new cable status. The default semantics is + * true: attached / false: detached. + * + * This function set the state of external connector and synchronize the data + * by usning a notification. + */ +int extcon_set_state_sync(struct extcon_dev *edev, unsigned int id, + bool cable_state) +{ + int ret, index; + unsigned long flags; + + index = find_cable_index_by_id(edev, id); + if (index < 0) + return index; + + /* Check whether the external connector's state is changed. */ + spin_lock_irqsave(&edev->lock, flags); + ret = is_extcon_changed(edev, index, cable_state); + spin_unlock_irqrestore(&edev->lock, flags); + if (!ret) + return 0; + + ret = extcon_set_state(edev, id, cable_state); + if (ret < 0) + return ret; + + return extcon_sync(edev, id); +} +EXPORT_SYMBOL_GPL(extcon_set_state_sync); + +/** * extcon_get_property() - Get the property value of a specific cable. * @edev: the extcon device that has the cable. * @id: the unique id of each external connector @@ -702,6 +737,31 @@ int extcon_set_property(struct extcon_dev *edev, unsigned int id, EXPORT_SYMBOL_GPL(extcon_set_property); /** + * extcon_set_property_sync() - Set the property value of a specific cable + with a notification. + * @prop_val: the pointer including the new value of property. + * + * When setting the property value of external connector, the external connector + * should be attached. The each property should be included in the list of + * supported properties according to the type of external connectors. + * + * Returns 0 if success or error number if fail + */ +int extcon_set_property_sync(struct extcon_dev *edev, unsigned int id, + unsigned int prop, + union extcon_property_value prop_val) +{ + int ret; + + ret = extcon_set_property(edev, id, prop, prop_val); + if (ret < 0) + return ret; + + return extcon_sync(edev, id); +} +EXPORT_SYMBOL_GPL(extcon_set_property_sync); + +/** * extcon_get_property_capability() - Get the capability of property * of an external connector. * @edev: the extcon device that has the cable. |