From 0548bf4f5ad6fc3bd93c4940fa48078b34609682 Mon Sep 17 00:00:00 2001
From: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
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 <javier.martinez@collabora.co.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>
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 <dianders@chromium.org>
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 <dianders@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
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 <geert@linux-m68k.org>
Date: Sun, 15 Mar 2015 14:03:50 +0100
Subject: [PATCH 3/3] regulator: tps65910: Add missing #include <linux/of.h>
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 <geert@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
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 <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
+#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>