[01/13] OMAP: Introduce a user list for each voltage domain instance in the voltage driver.

Message ID	4C7FF100.5090204@ti.com (mailing list archive)
State	Awaiting Upstream, archived
Headers	show Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id o82IkXwN003994 for <patchwork-omap@patchwork.kernel.org>; Thu, 2 Sep 2010 18:46:33 GMT Message-ID: <4C7FF100.5090204@ti.com> Date: Thu, 2 Sep 2010 13:46:24 -0500 From: Nishanth Menon <nm@ti.com> User-Agent: Thunderbird 2.0.0.24 (X11/20100411) MIME-Version: 1.0 To: Kevin Hilman <khilman@deeprootsystems.com> CC: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>, "Gopinath, Thara" <thara@ti.com>, "linux-omap@vger.kernel.org" <linux-omap@vger.kernel.org>, "paul@pwsan.com" <paul@pwsan.com>, "Sripathy, Vishwanath" <vishwanath.bs@ti.com>, "Sawant, Anand" <sawant@ti.com>, "Cousson, Benoit" <b-cousson@ti.com> Subject: Re: [PATCH 01/13] OMAP: Introduce a user list for each voltage domain instance in the voltage driver. References: <1282130412-12027-1-git-send-email-thara@ti.com> <1282130412-12027-2-git-send-email-thara@ti.com> <87eiddgjr7.fsf@deeprootsystems.com> <20100902094327.31a96174@surf> <4C7F5DB4.70306@ti.com> <87aao082bb.fsf@deeprootsystems.com> In-Reply-To: <87aao082bb.fsf@deeprootsystems.com> Content-Type: multipart/mixed; boundary="------------080804050009050506090306" Sender: linux-omap-owner@vger.kernel.org Precedence: bulk

From 3145fa45029fbdbfed2b2a2a6e335a72f8c47d36 Mon Sep 17 00:00:00 2001 From: Nishanth Menon <nm@ti.com> Date: Thu, 2 Sep 2010 13:40:40 -0500 Subject: {HACK}[PATCH 2/2] regulator: core: introduce unsafe operations introduce unsafe operations for consumers who can manage their own operation sequencing and dont want core to bother locking out multiple accesses exclusive of each other. Signed-off-by: Nishanth Menon <nm@ti.com> --- this patch is for demonstration purpose only drivers/regulator/core.c | 121 ++++++++++++++++++++++++++---------- include/linux/regulator/consumer.h | 2 + include/linux/regulator/driver.h | 1 + 3 files changed, 91 insertions(+), 33 deletions(-) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 0a1e199..c4c0e98 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -223,9 +223,11 @@ static ssize_t regulator_uV_show(struct device *dev, struct regulator_dev *rdev = dev_get_drvdata(dev); ssize_t ret; - mutex_lock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_lock(&rdev->mutex); ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev)); - mutex_unlock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_unlock(&rdev->mutex); return ret; } @@ -288,9 +290,11 @@ static ssize_t regulator_state_show(struct device *dev, struct regulator_dev *rdev = dev_get_drvdata(dev); ssize_t ret; - mutex_lock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_lock(&rdev->mutex); ret = regulator_print_state(buf, _regulator_is_enabled(rdev)); - mutex_unlock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_unlock(&rdev->mutex); return ret; } @@ -392,10 +396,12 @@ static ssize_t regulator_total_uA_show(struct device *dev, struct regulator *regulator; int uA = 0; - mutex_lock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_lock(&rdev->mutex); list_for_each_entry(regulator, &rdev->consumer_list, list) uA += regulator->uA_load; - mutex_unlock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_unlock(&rdev->mutex); return sprintf(buf, "%d\n", uA); } static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL); @@ -1078,7 +1084,7 @@ static int _regulator_get_enable_time(struct regulator_dev *rdev) /* Internal regulator request function */ static struct regulator *_regulator_get(struct device *dev, const char *id, - int exclusive) + int exclusive, int unsafe) { struct regulator_dev *rdev; struct regulator_map *map; @@ -1156,6 +1162,8 @@ found: else rdev->use_count = 0; } + if (unsafe) + rdev->flags |= REGULATOR_UNSAFEOPS_FLAG; out: mutex_unlock(&regulator_list_mutex); @@ -1178,7 +1186,7 @@ out: */ struct regulator *regulator_get(struct device *dev, const char *id) { - return _regulator_get(dev, id, 0); + return _regulator_get(dev, id, 0, 0); } EXPORT_SYMBOL_GPL(regulator_get); @@ -1205,11 +1213,27 @@ EXPORT_SYMBOL_GPL(regulator_get); */ struct regulator *regulator_get_exclusive(struct device *dev, const char *id) { - return _regulator_get(dev, id, 1); + return _regulator_get(dev, id, 1, 0); } EXPORT_SYMBOL_GPL(regulator_get_exclusive); /** + * regulator_get_exclusive_unsafe() - completely unsafe operations! + * @dev: device for regulator "consumer" + * @id: Supply name or regulator ID. + * + * Use of this function is strictly dangerous - caller should maintain + * exclusivity of access between operations, core will not take care of + * the same. this operation will fail unless the regulator can be + * exclusively openend + */ +struct regulator *regulator_get_exclusive_unsafe(struct device *dev, + const char *id) +{ + return _regulator_get(dev, id, 1, 1); +} +EXPORT_SYMBOL_GPL(regulator_get_exclusive); +/** * regulator_put - "free" the regulator source * @regulator: regulator source * @@ -1239,6 +1263,7 @@ void regulator_put(struct regulator *regulator) rdev->open_count--; rdev->flags &= ~REGULATOR_EXCLUSIVE_FLAG; + rdev->flags &= ~REGULATOR_UNSAFEOPS_FLAG; module_put(rdev->owner); mutex_unlock(&regulator_list_mutex); @@ -1340,9 +1365,11 @@ int regulator_enable(struct regulator *regulator) struct regulator_dev *rdev = regulator->rdev; int ret = 0; - mutex_lock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_lock(&rdev->mutex); ret = _regulator_enable(rdev); - mutex_unlock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_unlock(&rdev->mutex); return ret; } EXPORT_SYMBOL_GPL(regulator_enable); @@ -1409,9 +1436,11 @@ int regulator_disable(struct regulator *regulator) struct regulator_dev *rdev = regulator->rdev; int ret = 0; - mutex_lock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_lock(&rdev->mutex); ret = _regulator_disable(rdev); - mutex_unlock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_unlock(&rdev->mutex); return ret; } EXPORT_SYMBOL_GPL(regulator_disable); @@ -1456,10 +1485,12 @@ int regulator_force_disable(struct regulator *regulator) { int ret; - mutex_lock(&regulator->rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_lock(&regulator->rdev->mutex); regulator->uA_load = 0; ret = _regulator_force_disable(regulator->rdev); - mutex_unlock(&regulator->rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_unlock(&regulator->rdev->mutex); return ret; } EXPORT_SYMBOL_GPL(regulator_force_disable); @@ -1489,9 +1520,11 @@ int regulator_is_enabled(struct regulator *regulator) { int ret; - mutex_lock(&regulator->rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_lock(&regulator->rdev->mutex); ret = _regulator_is_enabled(regulator->rdev); - mutex_unlock(&regulator->rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_unlock(&regulator->rdev->mutex); return ret; } @@ -1532,9 +1565,11 @@ int regulator_list_voltage(struct regulator *regulator, unsigned selector) if (!ops->list_voltage || selector >= rdev->desc->n_voltages) return -EINVAL; - mutex_lock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_lock(&rdev->mutex); ret = ops->list_voltage(rdev, selector); - mutex_unlock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_unlock(&rdev->mutex); if (ret > 0) { if (ret < rdev->constraints->min_uV) @@ -1599,7 +1634,8 @@ int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV) struct regulator_dev *rdev = regulator->rdev; int ret; - mutex_lock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_lock(&rdev->mutex); /* sanity check */ if (!rdev->desc->ops->set_voltage) { @@ -1617,7 +1653,8 @@ int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV) out: _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE, NULL); - mutex_unlock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_unlock(&rdev->mutex); return ret; } EXPORT_SYMBOL_GPL(regulator_set_voltage); @@ -1644,11 +1681,13 @@ int regulator_get_voltage(struct regulator *regulator) { int ret; - mutex_lock(&regulator->rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_lock(&regulator->rdev->mutex); ret = _regulator_get_voltage(regulator->rdev); - mutex_unlock(&regulator->rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_unlock(&regulator->rdev->mutex); return ret; } @@ -1676,7 +1715,8 @@ int regulator_set_current_limit(struct regulator *regulator, struct regulator_dev *rdev = regulator->rdev; int ret; - mutex_lock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_lock(&rdev->mutex); /* sanity check */ if (!rdev->desc->ops->set_current_limit) { @@ -1691,7 +1731,8 @@ int regulator_set_current_limit(struct regulator *regulator, ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA); out: - mutex_unlock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_unlock(&rdev->mutex); return ret; } EXPORT_SYMBOL_GPL(regulator_set_current_limit); @@ -1700,7 +1741,8 @@ static int _regulator_get_current_limit(struct regulator_dev *rdev) { int ret; - mutex_lock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_lock(&rdev->mutex); /* sanity check */ if (!rdev->desc->ops->get_current_limit) { @@ -1710,7 +1752,8 @@ static int _regulator_get_current_limit(struct regulator_dev *rdev) ret = rdev->desc->ops->get_current_limit(rdev); out: - mutex_unlock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_unlock(&rdev->mutex); return ret; } @@ -1746,7 +1789,8 @@ int regulator_set_mode(struct regulator *regulator, unsigned int mode) int ret; int regulator_curr_mode; - mutex_lock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_lock(&rdev->mutex); /* sanity check */ if (!rdev->desc->ops->set_mode) { @@ -1770,7 +1814,8 @@ int regulator_set_mode(struct regulator *regulator, unsigned int mode) ret = rdev->desc->ops->set_mode(rdev, mode); out: - mutex_unlock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_unlock(&rdev->mutex); return ret; } EXPORT_SYMBOL_GPL(regulator_set_mode); @@ -1779,7 +1824,8 @@ static unsigned int _regulator_get_mode(struct regulator_dev *rdev) { int ret; - mutex_lock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_lock(&rdev->mutex); /* sanity check */ if (!rdev->desc->ops->get_mode) { @@ -1789,7 +1835,8 @@ static unsigned int _regulator_get_mode(struct regulator_dev *rdev) ret = rdev->desc->ops->get_mode(rdev); out: - mutex_unlock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_unlock(&rdev->mutex); return ret; } @@ -1838,7 +1885,8 @@ int regulator_set_optimum_mode(struct regulator *regulator, int uA_load) int ret, output_uV, input_uV, total_uA_load = 0; unsigned int mode; - mutex_lock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_lock(&rdev->mutex); regulator->uA_load = uA_load; ret = regulator_check_drms(rdev); @@ -1892,7 +1940,8 @@ int regulator_set_optimum_mode(struct regulator *regulator, int uA_load) } ret = mode; out: - mutex_unlock(&rdev->mutex); + if (!(rdev->flags & REGULATOR_UNSAFEOPS_FLAG)) + mutex_unlock(&rdev->mutex); return ret; } EXPORT_SYMBOL_GPL(regulator_set_optimum_mode); @@ -1934,6 +1983,9 @@ static void _notifier_call_chain(struct regulator_dev *rdev, unsigned long event, void *data) { struct regulator_dev *_rdev; + /* We will not have notifiers in this mode */ + if (rdev->flags & REGULATOR_UNSAFEOPS_FLAG) + return; /* call rdev chain first */ blocking_notifier_call_chain(&rdev->notifier, event, NULL); @@ -2423,6 +2475,9 @@ int regulator_suspend_prepare(suspend_state_t state) /* ON is handled by regulator active state */ if (state == PM_SUSPEND_ON) return -EINVAL; + /* we will not suspend if we are opened unsafe */ + if (rdev->flags & REGULATOR_UNSAFEOPS_FLAG) + return -EINVAL; mutex_lock(&regulator_list_mutex); list_for_each_entry(rdev, &regulator_list, list) { diff --git a/include/linux/regulator/consumer.h b/include/linux/regulator/consumer.h index ebd7472..c071992 100644 --- a/include/linux/regulator/consumer.h +++ b/include/linux/regulator/consumer.h @@ -131,6 +131,8 @@ struct regulator *__must_check regulator_get(struct device *dev, const char *id); struct regulator *__must_check regulator_get_exclusive(struct device *dev, const char *id); +struct regulator *__must_check regulator_get_exclusive_unsafe(struct device *dev, + const char *id); void regulator_put(struct regulator *regulator); /* regulator output control and status */ diff --git a/include/linux/regulator/driver.h b/include/linux/regulator/driver.h index 6397ab3..6d117d9 100644 --- a/include/linux/regulator/driver.h +++ b/include/linux/regulator/driver.h @@ -157,6 +157,7 @@ struct regulator_desc { }; #define REGULATOR_EXCLUSIVE_FLAG (0x1 << 1) +#define REGULATOR_UNSAFEOPS_FLAG (0x2 << 1) /* * struct regulator_dev -- 1.6.3.3

[01/13] OMAP: Introduce a user list for each voltage domain instance in the voltage driver.

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Patch