From 0548bf4f5ad6fc3bd93c4940fa48078b34609682 Mon Sep 17 00:00:00 2001 From: Javier Martinez Canillas Date: Mon, 2 Mar 2015 21:40:39 +0100 Subject: [PATCH 1/3] regulator: Only enable disabled regulators on resume The _regulator_do_enable() call ought to be a no-op when called on an already-enabled regulator. However, as an optimization _regulator_enable() doesn't call _regulator_do_enable() on an already enabled regulator. That means we never test the case of calling _regulator_do_enable() during normal usage and there may be hidden bugs or warnings. We have seen warnings issued by the tps65090 driver and bugs when using the GPIO enable pin. Let's match the same optimization that _regulator_enable() in regulator_suspend_finish(). That may speed up suspend/resume and also avoids exposing hidden bugs. [Use much clearer commit message from Doug Anderson] Signed-off-by: Javier Martinez Canillas Signed-off-by: Mark Brown Cc: stable@vger.kernel.org --- drivers/regulator/core.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index b899947d839d..0e271e57504a 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -3807,9 +3807,11 @@ int regulator_suspend_finish(void) list_for_each_entry(rdev, ®ulator_list, list) { mutex_lock(&rdev->mutex); if (rdev->use_count > 0 || rdev->constraints->always_on) { - error = _regulator_do_enable(rdev); - if (error) - ret = error; + if (!_regulator_is_enabled(rdev)) { + error = _regulator_do_enable(rdev); + if (error) + ret = error; + } } else { if (!have_full_constraints()) goto unlock; From 29d62ec5f87fbeec8413e2215ddad12e7f972e4c Mon Sep 17 00:00:00 2001 From: Doug Anderson Date: Tue, 3 Mar 2015 15:20:47 -0800 Subject: [PATCH 2/3] regulator: core: Fix enable GPIO reference counting Normally _regulator_do_enable() isn't called on an already-enabled rdev. That's because the main caller, _regulator_enable() always calls _regulator_is_enabled() and only calls _regulator_do_enable() if the rdev was not already enabled. However, there is one caller of _regulator_do_enable() that doesn't check: regulator_suspend_finish(). While we might want to make regulator_suspend_finish() behave more like _regulator_enable(), it's probably also a good idea to make _regulator_do_enable() robust if it is called on an already enabled rdev. At the moment, _regulator_do_enable() is _not_ robust for already enabled rdevs if we're using an ena_pin. Each time _regulator_do_enable() is called for an rdev using an ena_pin the reference count of the ena_pin is incremented even if the rdev was already enabled. This is not as intended because the ena_pin is for something else: for keeping track of how many active rdevs there are sharing the same ena_pin. Here's how the reference counting works here: * Each time _regulator_enable() is called we increment rdev->use_count, so _regulator_enable() calls need to be balanced with _regulator_disable() calls. * There is no explicit reference counting in _regulator_do_enable() which is normally just a warapper around rdev->desc->ops->enable() with code for supporting delays. It's not expected that the "ops->enable()" call do reference counting. * Since regulator_ena_gpio_ctrl() does have reference counting (handling the sharing of the pin amongst multiple rdevs), we shouldn't call it if the current rdev is already enabled. Note that as part of this we cleanup (remove) the initting of ena_gpio_state in regulator_register(). In _regulator_do_enable(), _regulator_do_disable() and _regulator_is_enabled() is is clear that ena_gpio_state should be the state of whether this particular rdev has requested the GPIO be enabled. regulator_register() was initting it as the actual state of the pin. Fixes: 967cfb18c0e3 ("regulator: core: manage enable GPIO list") Signed-off-by: Doug Anderson Signed-off-by: Mark Brown Cc: stable@vger.kernel.org --- drivers/regulator/core.c | 26 ++++++++++++-------------- 1 file changed, 12 insertions(+), 14 deletions(-) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 0e271e57504a..fafeb32427c1 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1839,10 +1839,12 @@ static int _regulator_do_enable(struct regulator_dev *rdev) } if (rdev->ena_pin) { - ret = regulator_ena_gpio_ctrl(rdev, true); - if (ret < 0) - return ret; - rdev->ena_gpio_state = 1; + if (!rdev->ena_gpio_state) { + ret = regulator_ena_gpio_ctrl(rdev, true); + if (ret < 0) + return ret; + rdev->ena_gpio_state = 1; + } } else if (rdev->desc->ops->enable) { ret = rdev->desc->ops->enable(rdev); if (ret < 0) @@ -1939,10 +1941,12 @@ static int _regulator_do_disable(struct regulator_dev *rdev) trace_regulator_disable(rdev_get_name(rdev)); if (rdev->ena_pin) { - ret = regulator_ena_gpio_ctrl(rdev, false); - if (ret < 0) - return ret; - rdev->ena_gpio_state = 0; + if (rdev->ena_gpio_state) { + ret = regulator_ena_gpio_ctrl(rdev, false); + if (ret < 0) + return ret; + rdev->ena_gpio_state = 0; + } } else if (rdev->desc->ops->disable) { ret = rdev->desc->ops->disable(rdev); @@ -3633,12 +3637,6 @@ regulator_register(const struct regulator_desc *regulator_desc, config->ena_gpio, ret); goto wash; } - - if (config->ena_gpio_flags & GPIOF_OUT_INIT_HIGH) - rdev->ena_gpio_state = 1; - - if (config->ena_gpio_invert) - rdev->ena_gpio_state = !rdev->ena_gpio_state; } /* set regulator constraints */ From d16da513c9c8f394216b8dd7c258e667b2c43c74 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Sun, 15 Mar 2015 14:03:50 +0100 Subject: [PATCH 3/3] regulator: tps65910: Add missing #include MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit drivers/regulator/tps65910-regulator.c: In function ‘tps65910_parse_dt_reg_data’: drivers/regulator/tps65910-regulator.c:1018: error: implicit declaration of function ‘of_get_child_by_name’ drivers/regulator/tps65910-regulator.c:1018: warning: assignment makes pointer from integer without a cast drivers/regulator/tps65910-regulator.c:1034: error: implicit declaration of function ‘of_node_put’ drivers/regulator/tps65910-regulator.c:1056: error: implicit declaration of function ‘of_property_read_u32’ Signed-off-by: Geert Uytterhoeven Signed-off-by: Mark Brown --- drivers/regulator/tps65910-regulator.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/regulator/tps65910-regulator.c b/drivers/regulator/tps65910-regulator.c index e2cffe01b807..fb991ec76423 100644 --- a/drivers/regulator/tps65910-regulator.c +++ b/drivers/regulator/tps65910-regulator.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include #include