From 7179569aeb52197fd2a9909ba226c4c9cc0e2e2a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Heiko=20St=C3=BCbner?= Date: Thu, 28 Aug 2014 12:36:04 -0700 Subject: [PATCH] regulator: core: Add REGULATOR_EVENT_PRE_VOLTAGE_CHANGE (and ABORT) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In some cases we need to know when a regulator is about to be changed. Add a way for clients to be notified. Note that for set_voltage() we don't necessarily know what voltage we'll end up with, so we tell the client what the range will be so they can prepare. Signed-off-by: Heiko Stübner Signed-off-by: Doug Anderson Signed-off-by: Mark Brown --- drivers/regulator/core.c | 63 ++++++++++++++++++++++++++---- include/linux/regulator/consumer.h | 20 ++++++++++ 2 files changed, 76 insertions(+), 7 deletions(-) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index a3c3785901f5..dabc8e8862c8 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -102,7 +102,7 @@ static int _regulator_disable(struct regulator_dev *rdev); static int _regulator_get_voltage(struct regulator_dev *rdev); static int _regulator_get_current_limit(struct regulator_dev *rdev); static unsigned int _regulator_get_mode(struct regulator_dev *rdev); -static void _notifier_call_chain(struct regulator_dev *rdev, +static int _notifier_call_chain(struct regulator_dev *rdev, unsigned long event, void *data); static int _regulator_do_set_voltage(struct regulator_dev *rdev, int min_uV, int max_uV); @@ -2369,6 +2369,55 @@ int regulator_is_supported_voltage(struct regulator *regulator, } EXPORT_SYMBOL_GPL(regulator_is_supported_voltage); +static int _regulator_call_set_voltage(struct regulator_dev *rdev, + int min_uV, int max_uV, + unsigned *selector) +{ + struct pre_voltage_change_data data; + int ret; + + data.old_uV = _regulator_get_voltage(rdev); + data.min_uV = min_uV; + data.max_uV = max_uV; + ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE, + &data); + if (ret & NOTIFY_STOP_MASK) + return -EINVAL; + + ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, selector); + if (ret >= 0) + return ret; + + _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE, + (void *)data.old_uV); + + return ret; +} + +static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev, + int uV, unsigned selector) +{ + struct pre_voltage_change_data data; + int ret; + + data.old_uV = _regulator_get_voltage(rdev); + data.min_uV = uV; + data.max_uV = uV; + ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE, + &data); + if (ret & NOTIFY_STOP_MASK) + return -EINVAL; + + ret = rdev->desc->ops->set_voltage_sel(rdev, selector); + if (ret >= 0) + return ret; + + _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE, + (void *)data.old_uV); + + return ret; +} + static int _regulator_do_set_voltage(struct regulator_dev *rdev, int min_uV, int max_uV) { @@ -2396,8 +2445,8 @@ static int _regulator_do_set_voltage(struct regulator_dev *rdev, } if (rdev->desc->ops->set_voltage) { - ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, - &selector); + ret = _regulator_call_set_voltage(rdev, min_uV, max_uV, + &selector); if (ret >= 0) { if (rdev->desc->ops->list_voltage) @@ -2432,8 +2481,8 @@ static int _regulator_do_set_voltage(struct regulator_dev *rdev, if (old_selector == selector) ret = 0; else - ret = rdev->desc->ops->set_voltage_sel( - rdev, ret); + ret = _regulator_call_set_voltage_sel( + rdev, best_val, selector); } else { ret = -EINVAL; } @@ -3079,11 +3128,11 @@ EXPORT_SYMBOL_GPL(regulator_unregister_notifier); /* notify regulator consumers and downstream regulator consumers. * Note mutex must be held by caller. */ -static void _notifier_call_chain(struct regulator_dev *rdev, +static int _notifier_call_chain(struct regulator_dev *rdev, unsigned long event, void *data) { /* call rdev chain first */ - blocking_notifier_call_chain(&rdev->notifier, event, data); + return blocking_notifier_call_chain(&rdev->notifier, event, data); } /** diff --git a/include/linux/regulator/consumer.h b/include/linux/regulator/consumer.h index f8a8733068a7..d347c805f923 100644 --- a/include/linux/regulator/consumer.h +++ b/include/linux/regulator/consumer.h @@ -93,7 +93,12 @@ struct regmap; * OVER_TEMP Regulator over temp. * FORCE_DISABLE Regulator forcibly shut down by software. * VOLTAGE_CHANGE Regulator voltage changed. + * Data passed is old voltage cast to (void *). * DISABLE Regulator was disabled. + * PRE_VOLTAGE_CHANGE Regulator is about to have voltage changed. + * Data passed is "struct pre_voltage_change_data" + * ABORT_VOLTAGE_CHANGE Regulator voltage change failed for some reason. + * Data passed is old voltage cast to (void *). * * NOTE: These events can be OR'ed together when passed into handler. */ @@ -106,6 +111,21 @@ struct regmap; #define REGULATOR_EVENT_FORCE_DISABLE 0x20 #define REGULATOR_EVENT_VOLTAGE_CHANGE 0x40 #define REGULATOR_EVENT_DISABLE 0x80 +#define REGULATOR_EVENT_PRE_VOLTAGE_CHANGE 0x100 +#define REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE 0x200 + +/** + * struct pre_voltage_change_data - Data sent with PRE_VOLTAGE_CHANGE event + * + * @old_uV: Current voltage before change. + * @min_uV: Min voltage we'll change to. + * @max_uV: Max voltage we'll change to. + */ +struct pre_voltage_change_data { + unsigned long old_uV; + unsigned long min_uV; + unsigned long max_uV; +}; struct regulator;