From e733a2fb8cbcff0747108cb529ffb4e4a00465ac Mon Sep 17 00:00:00 2001
From: Aaron Lu <aaron.lu@intel.com>
Date: Mon, 12 Jan 2015 10:09:32 +0800
Subject: [PATCH 01/11] gpio: crystalcove: use handle_nested_irq
The CrystalCove GPIO chip has can_sleep set so its demultiplexed irqs
will have IRQ_NESTED_THREAD flag set, thus we should use the nested
version handle_nested_irq in CrystalCove's irq handler instead of
handle_generic_irq, or the following warning will be hit and the
functionality is lost:
[ 4089.639554] Hardware name: ASUSTeK COMPUTER INC. T100TA/T100TA, BIOS T100TA.313 08/13/2014
[ 4089.639564] 00000002 00000000 c24fbdf4 c16e0257 c24fbe38 c24fbe28 c105390c c18ec480
[ 4089.639596] c24fbe54 00000048 c18f8e3b 00000295 c10a60fc 00000295 c10a60fc f4464540
[ 4089.639626] f446459c c278ad40 c24fbe40 c1053974 00000009 c24fbe38 c18ec480 c24fbe54
[ 4089.639656] Call Trace:
[ 4089.639685] [<c16e0257>] dump_stack+0x41/0x52
[ 4089.639707] [<c105390c>] warn_slowpath_common+0x8c/0xc0
[ 4089.639727] [<c10a60fc>] ? irq_nested_primary_handler+0x2c/0x30
[ 4089.639744] [<c10a60fc>] ? irq_nested_primary_handler+0x2c/0x30
[ 4089.639763] [<c1053974>] warn_slowpath_fmt+0x34/0x40
[ 4089.639781] [<c10a60fc>] irq_nested_primary_handler+0x2c/0x30
[ 4089.639800] [<c10a5c56>] handle_irq_event_percpu+0x76/0x190
[ 4089.639818] [<c1461570>] ? regmap_format_10_14_write+0x30/0x30
[ 4089.639836] [<c1464f4c>] ? _regmap_bus_raw_write+0x4c/0x70
[ 4089.639854] [<c10a5da1>] handle_irq_event+0x31/0x50
[ 4089.639872] [<c10a83eb>] handle_simple_irq+0x4b/0x70
[ 4089.639889] [<c10a5384>] generic_handle_irq+0x24/0x40
[ 4089.639908] [<c1366d87>] crystalcove_gpio_irq_handler+0xa7/0xc0
[ 4089.639927] [<c10a85a7>] handle_nested_irq+0x77/0x190
[ 4089.639947] [<c1469801>] regmap_irq_thread+0x1b1/0x360
[ 4089.639966] [<c10a6ae8>] irq_thread_fn+0x18/0x30
[ 4089.639983] [<c10a6906>] irq_thread+0xf6/0x110
[ 4089.640001] [<c10a6ad0>] ? irq_finalize_oneshot.part.30+0x1b0/0x1b0
[ 4089.640019] [<c10a6b50>] ? irq_forced_thread_fn+0x50/0x50
[ 4089.640037] [<c10a6810>] ? irq_thread_check_affinity+0xc0/0xc0
[ 4089.640054] [<c106f389>] kthread+0xa9/0xc0
[ 4089.640074] [<c16e6401>] ret_from_kernel_thread+0x21/0x30
[ 4089.640091] [<c106f2e0>] ? kthread_create_on_node+0x110/0x110
[ 4089.640105] ---[ end trace dca7946ad31eba7d ]---
Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=90521
Reported-and-tested-by: Brian Loften <bloften80@gmail.com>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/gpio/gpio-crystalcove.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpio/gpio-crystalcove.c b/drivers/gpio/gpio-crystalcove.c
index 55d4803d71b0d..3d9e08f7e823e 100644
--- a/drivers/gpio/gpio-crystalcove.c
+++ b/drivers/gpio/gpio-crystalcove.c
@@ -272,7 +272,7 @@ static irqreturn_t crystalcove_gpio_irq_handler(int irq, void *data)
for (gpio = 0; gpio < CRYSTALCOVE_GPIO_NUM; gpio++) {
if (pending & BIT(gpio)) {
virq = irq_find_mapping(cg->chip.irqdomain, gpio);
- generic_handle_irq(virq);
+ handle_nested_irq(virq);
}
}
From 5539b3c938d64a60cb1fc442ac3ce9263d52de0c Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Mon, 12 Jan 2015 17:12:24 +0100
Subject: [PATCH 02/11] gpio: fix memory and reference leaks in gpiochip_add
error path
Memory allocated and references taken by of_gpiochip_add and
acpi_gpiochip_add were never released on errors in gpiochip_add (e.g.
failure to find free gpio range).
Fixes: 391c970c0dd1 ("of/gpio: add default of_xlate function if device
has a node pointer")
Fixes: 664e3e5ac64c ("gpio / ACPI: register to ACPI events
automatically")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/gpio/gpiolib.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 487afe6f22fcd..89c59f5f19240 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -277,6 +277,9 @@ int gpiochip_add(struct gpio_chip *chip)
spin_unlock_irqrestore(&gpio_lock, flags);
+ if (status)
+ goto fail;
+
#ifdef CONFIG_PINCTRL
INIT_LIST_HEAD(&chip->pin_ranges);
#endif
@@ -284,12 +287,12 @@ int gpiochip_add(struct gpio_chip *chip)
of_gpiochip_add(chip);
acpi_gpiochip_add(chip);
- if (status)
- goto fail;
-
status = gpiochip_export(chip);
- if (status)
+ if (status) {
+ acpi_gpiochip_remove(chip);
+ of_gpiochip_remove(chip);
goto fail;
+ }
pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__,
chip->base, chip->base + chip->ngpio - 1,
From 225fce83cb72e1bffb712a33ce47c210c770f8ab Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Mon, 12 Jan 2015 17:12:25 +0100
Subject: [PATCH 03/11] gpio: fix gpio-chip list corruption
Fix potential corruption of gpio-chip list due to failure to remove the
chip from the list before returning in gpiochip_add error path.
The chip could be long gone when the global list is next traversed,
something which could lead to a null-pointer dereference. In the best
case (chip not deallocated) we are just leaking the gpio range.
Fixes: 14e85c0e69d5 ("gpio: remove gpio_descs global array")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/gpio/gpiolib.c | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 89c59f5f19240..ac5944b4e4d88 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -248,7 +248,8 @@ int gpiochip_add(struct gpio_chip *chip)
base = gpiochip_find_base(chip->ngpio);
if (base < 0) {
status = base;
- goto unlock;
+ spin_unlock_irqrestore(&gpio_lock, flags);
+ goto err_free_descs;
}
chip->base = base;
}
@@ -288,11 +289,8 @@ int gpiochip_add(struct gpio_chip *chip)
acpi_gpiochip_add(chip);
status = gpiochip_export(chip);
- if (status) {
- acpi_gpiochip_remove(chip);
- of_gpiochip_remove(chip);
- goto fail;
- }
+ if (status)
+ goto err_remove_chip;
pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__,
chip->base, chip->base + chip->ngpio - 1,
@@ -300,9 +298,14 @@ int gpiochip_add(struct gpio_chip *chip)
return 0;
-unlock:
+err_remove_chip:
+ acpi_gpiochip_remove(chip);
+ of_gpiochip_remove(chip);
+ spin_lock_irqsave(&gpio_lock, flags);
+ list_del(&chip->list);
spin_unlock_irqrestore(&gpio_lock, flags);
fail:
+err_free_descs:
kfree(descs);
chip->desc = NULL;
From 05aa52033494a13178fb550660aea87cd8a99cfd Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Mon, 12 Jan 2015 17:12:26 +0100
Subject: [PATCH 04/11] gpio: clean up gpiochip_add error handling
Clean up gpiochip_add error handling.
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/gpio/gpiolib.c | 38 +++++++++++++++++---------------------
1 file changed, 17 insertions(+), 21 deletions(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index ac5944b4e4d88..4efb92ca34631 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -255,32 +255,29 @@ int gpiochip_add(struct gpio_chip *chip)
}
status = gpiochip_add_to_list(chip);
+ if (status) {
+ spin_unlock_irqrestore(&gpio_lock, flags);
+ goto err_free_descs;
+ }
- if (status == 0) {
- for (id = 0; id < chip->ngpio; id++) {
- struct gpio_desc *desc = &descs[id];
- desc->chip = chip;
-
- /* REVISIT: most hardware initializes GPIOs as
- * inputs (often with pullups enabled) so power
- * usage is minimized. Linux code should set the
- * gpio direction first thing; but until it does,
- * and in case chip->get_direction is not set,
- * we may expose the wrong direction in sysfs.
- */
- desc->flags = !chip->direction_input
- ? (1 << FLAG_IS_OUT)
- : 0;
- }
+ for (id = 0; id < chip->ngpio; id++) {
+ struct gpio_desc *desc = &descs[id];
+
+ desc->chip = chip;
+
+ /* REVISIT: most hardware initializes GPIOs as inputs (often
+ * with pullups enabled) so power usage is minimized. Linux
+ * code should set the gpio direction first thing; but until
+ * it does, and in case chip->get_direction is not set, we may
+ * expose the wrong direction in sysfs.
+ */
+ desc->flags = !chip->direction_input ? (1 << FLAG_IS_OUT) : 0;
}
chip->desc = descs;
spin_unlock_irqrestore(&gpio_lock, flags);
- if (status)
- goto fail;
-
#ifdef CONFIG_PINCTRL
INIT_LIST_HEAD(&chip->pin_ranges);
#endif
@@ -304,10 +301,9 @@ int gpiochip_add(struct gpio_chip *chip)
spin_lock_irqsave(&gpio_lock, flags);
list_del(&chip->list);
spin_unlock_irqrestore(&gpio_lock, flags);
-fail:
+ chip->desc = NULL;
err_free_descs:
kfree(descs);
- chip->desc = NULL;
/* failures here can mean systems won't boot... */
pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__,
From 00acc3dc248063f982cfacfbe5e78c0d6797ffef Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Mon, 12 Jan 2015 17:12:27 +0100
Subject: [PATCH 05/11] gpio: fix memory leak and sleep-while-atomic
Fix memory leak and sleep-while-atomic in gpiochip_remove.
The memory leak was introduced by afa82fab5e13 ("gpio / ACPI: Move event
handling registration to gpiolib irqchip helpers") that moved the
release of acpi interrupt resources to gpiochip_irqchip_remove, but by
then the resources are no longer accessible as the acpi_gpio_chip has
already been freed by acpi_gpiochip_remove.
Note that this also fixes a few potential sleep-while-atomics, which has
been around since 1425052097b5 ("gpio: add IRQ chip helpers in gpiolib")
when the call to gpiochip_irqchip_remove while holding a spinlock was
added (a couple of irq-domain paths can end up grabbing mutexes).
Fixes: afa82fab5e13 ("gpio / ACPI: Move event handling registration to
gpiolib irqchip helpers")
Fixes: 1425052097b5 ("gpio: add IRQ chip helpers in gpiolib")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/gpio/gpiolib.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 4efb92ca34631..0f8173051edca 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -327,11 +327,12 @@ void gpiochip_remove(struct gpio_chip *chip)
unsigned long flags;
unsigned id;
+ gpiochip_irqchip_remove(chip);
+
acpi_gpiochip_remove(chip);
spin_lock_irqsave(&gpio_lock, flags);
- gpiochip_irqchip_remove(chip);
gpiochip_remove_pin_ranges(chip);
of_gpiochip_remove(chip);
From 6798acaa0138d8b12f1c54402ebcb66fea3deb03 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Mon, 12 Jan 2015 17:12:28 +0100
Subject: [PATCH 06/11] gpio: fix sleep-while-atomic in gpiochip_remove
Move direct and indirect calls to gpiochip_remove_pin_ranges outside of
spin lock as they can end up taking a mutex in pinctrl_remove_gpio_range.
Note that the pin ranges are already added outside of the lock.
Fixes: 9ef0d6f7628b ("gpiolib: call pin removal in chip removal function")
Fixes: f23f1516b675 ("gpiolib: provide provision to register pin ranges")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/gpio/gpiolib.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 0f8173051edca..37f919dc2cb47 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -330,12 +330,10 @@ void gpiochip_remove(struct gpio_chip *chip)
gpiochip_irqchip_remove(chip);
acpi_gpiochip_remove(chip);
-
- spin_lock_irqsave(&gpio_lock, flags);
-
gpiochip_remove_pin_ranges(chip);
of_gpiochip_remove(chip);
+ spin_lock_irqsave(&gpio_lock, flags);
for (id = 0; id < chip->ngpio; id++) {
if (test_bit(FLAG_REQUESTED, &chip->desc[id].flags))
dev_crit(chip->dev, "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
From 01cca93a9491ed95992523ff7e79dd9bfcdea8e0 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Mon, 12 Jan 2015 17:12:29 +0100
Subject: [PATCH 07/11] gpio: unregister gpiochip device before removing it
Unregister gpiochip device (used to export information through sysfs)
before removing it internally. This way removal will reverse addition.
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/gpio/gpiolib.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 37f919dc2cb47..568aa2b6bdb01 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -327,6 +327,8 @@ void gpiochip_remove(struct gpio_chip *chip)
unsigned long flags;
unsigned id;
+ gpiochip_unexport(chip);
+
gpiochip_irqchip_remove(chip);
acpi_gpiochip_remove(chip);
@@ -343,7 +345,6 @@ void gpiochip_remove(struct gpio_chip *chip)
list_del(&chip->list);
spin_unlock_irqrestore(&gpio_lock, flags);
- gpiochip_unexport(chip);
kfree(chip->desc);
chip->desc = NULL;
From 121b6a79955a3a3fd7bbb9b8cb88d5b9dad6283d Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Tue, 13 Jan 2015 13:00:04 +0100
Subject: [PATCH 08/11] gpio: sysfs: fix gpio-chip device-attribute leak
The gpio-chip device attributes were never destroyed when the device was
removed.
Fix by using device_create_with_groups() to create the device attributes
of the chip class device.
Note that this also fixes the attribute-creation race with userspace.
Fixes: d8f388d8dc8d ("gpio: sysfs interface")
Cc: stable <stable@vger.kernel.org> # v2.6.27+
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/gpio/gpiolib-sysfs.c | 19 ++++++++-----------
1 file changed, 8 insertions(+), 11 deletions(-)
diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index 2ac1800b58bb7..33cf4bd0ed2d5 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -400,16 +400,13 @@ static ssize_t chip_ngpio_show(struct device *dev,
}
static DEVICE_ATTR(ngpio, 0444, chip_ngpio_show, NULL);
-static const struct attribute *gpiochip_attrs[] = {
+static struct attribute *gpiochip_attrs[] = {
&dev_attr_base.attr,
&dev_attr_label.attr,
&dev_attr_ngpio.attr,
NULL,
};
-
-static const struct attribute_group gpiochip_attr_group = {
- .attrs = (struct attribute **) gpiochip_attrs,
-};
+ATTRIBUTE_GROUPS(gpiochip);
/*
* /sys/class/gpio/export ... write-only
@@ -750,13 +747,13 @@ int gpiochip_export(struct gpio_chip *chip)
/* use chip->base for the ID; it's already known to be unique */
mutex_lock(&sysfs_lock);
- dev = device_create(&gpio_class, chip->dev, MKDEV(0, 0), chip,
- "gpiochip%d", chip->base);
- if (!IS_ERR(dev)) {
- status = sysfs_create_group(&dev->kobj,
- &gpiochip_attr_group);
- } else
+ dev = device_create_with_groups(&gpio_class, chip->dev, MKDEV(0, 0),
+ chip, gpiochip_groups,
+ "gpiochip%d", chip->base);
+ if (IS_ERR(dev))
status = PTR_ERR(dev);
+ else
+ status = 0;
chip->exported = (status == 0);
mutex_unlock(&sysfs_lock);
From 0915e6feb38de8d3601819992a5bd050201a56fa Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Tue, 13 Jan 2015 13:00:05 +0100
Subject: [PATCH 09/11] gpio: sysfs: fix gpio device-attribute leak
The gpio device attributes were never destroyed when the gpio was
unexported (or on export failures).
Use device_create_with_groups() to create the default device attributes
of the gpio class device. Note that this also fixes the
attribute-creation race with userspace for these attributes.
Remove contingent attributes in export error path and on unexport.
Fixes: d8f388d8dc8d ("gpio: sysfs interface")
Cc: stable <stable@vger.kernel.org> # v2.6.27+
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/gpio/gpiolib-sysfs.c | 28 +++++++++++++---------------
1 file changed, 13 insertions(+), 15 deletions(-)
diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index 33cf4bd0ed2d5..fd4d9423f6e6a 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -128,7 +128,7 @@ static ssize_t gpio_value_store(struct device *dev,
return status;
}
-static const DEVICE_ATTR(value, 0644,
+static DEVICE_ATTR(value, 0644,
gpio_value_show, gpio_value_store);
static irqreturn_t gpio_sysfs_irq(int irq, void *priv)
@@ -353,18 +353,15 @@ static ssize_t gpio_active_low_store(struct device *dev,
return status ? : size;
}
-static const DEVICE_ATTR(active_low, 0644,
+static DEVICE_ATTR(active_low, 0644,
gpio_active_low_show, gpio_active_low_store);
-static const struct attribute *gpio_attrs[] = {
+static struct attribute *gpio_attrs[] = {
&dev_attr_value.attr,
&dev_attr_active_low.attr,
NULL,
};
-
-static const struct attribute_group gpio_attr_group = {
- .attrs = (struct attribute **) gpio_attrs,
-};
+ATTRIBUTE_GROUPS(gpio);
/*
* /sys/class/gpio/gpiochipN/
@@ -561,18 +558,15 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
if (desc->chip->names && desc->chip->names[offset])
ioname = desc->chip->names[offset];
- dev = device_create(&gpio_class, desc->chip->dev, MKDEV(0, 0),
- desc, ioname ? ioname : "gpio%u",
- desc_to_gpio(desc));
+ dev = device_create_with_groups(&gpio_class, desc->chip->dev,
+ MKDEV(0, 0), desc, gpio_groups,
+ ioname ? ioname : "gpio%u",
+ desc_to_gpio(desc));
if (IS_ERR(dev)) {
status = PTR_ERR(dev);
goto fail_unlock;
}
- status = sysfs_create_group(&dev->kobj, &gpio_attr_group);
- if (status)
- goto fail_unregister_device;
-
if (direction_may_change) {
status = device_create_file(dev, &dev_attr_direction);
if (status)
@@ -583,13 +577,15 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
!test_bit(FLAG_IS_OUT, &desc->flags))) {
status = device_create_file(dev, &dev_attr_edge);
if (status)
- goto fail_unregister_device;
+ goto fail_remove_attr_direction;
}
set_bit(FLAG_EXPORT, &desc->flags);
mutex_unlock(&sysfs_lock);
return 0;
+fail_remove_attr_direction:
+ device_remove_file(dev, &dev_attr_direction);
fail_unregister_device:
device_unregister(dev);
fail_unlock:
@@ -723,6 +719,8 @@ void gpiod_unexport(struct gpio_desc *desc)
mutex_unlock(&sysfs_lock);
if (dev) {
+ device_remove_file(dev, &dev_attr_edge);
+ device_remove_file(dev, &dev_attr_direction);
device_unregister(dev);
put_device(dev);
}
From ebbeba120ab2ec6ac5f3afc1425ec6ff0b77ad6f Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Tue, 13 Jan 2015 13:00:06 +0100
Subject: [PATCH 10/11] gpio: sysfs: fix gpio attribute-creation race
Fix attribute-creation race with userspace by using the default group
to create also the contingent gpio device attributes.
Fixes: d8f388d8dc8d ("gpio: sysfs interface")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/gpio/gpiolib-sysfs.c | 61 +++++++++++++++++++++++-------------
drivers/gpio/gpiolib.h | 1 +
2 files changed, 40 insertions(+), 22 deletions(-)
diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index fd4d9423f6e6a..f62aa115d79ab 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -356,12 +356,44 @@ static ssize_t gpio_active_low_store(struct device *dev,
static DEVICE_ATTR(active_low, 0644,
gpio_active_low_show, gpio_active_low_store);
+static umode_t gpio_is_visible(struct kobject *kobj, struct attribute *attr,
+ int n)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct gpio_desc *desc = dev_get_drvdata(dev);
+ umode_t mode = attr->mode;
+ bool show_direction = test_bit(FLAG_SYSFS_DIR, &desc->flags);
+
+ if (attr == &dev_attr_direction.attr) {
+ if (!show_direction)
+ mode = 0;
+ } else if (attr == &dev_attr_edge.attr) {
+ if (gpiod_to_irq(desc) < 0)
+ mode = 0;
+ if (!show_direction && test_bit(FLAG_IS_OUT, &desc->flags))
+ mode = 0;
+ }
+
+ return mode;
+}
+
static struct attribute *gpio_attrs[] = {
+ &dev_attr_direction.attr,
+ &dev_attr_edge.attr,
&dev_attr_value.attr,
&dev_attr_active_low.attr,
NULL,
};
-ATTRIBUTE_GROUPS(gpio);
+
+static const struct attribute_group gpio_group = {
+ .attrs = gpio_attrs,
+ .is_visible = gpio_is_visible,
+};
+
+static const struct attribute_group *gpio_groups[] = {
+ &gpio_group,
+ NULL
+};
/*
* /sys/class/gpio/gpiochipN/
@@ -550,8 +582,11 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
goto fail_unlock;
}
- if (!desc->chip->direction_input || !desc->chip->direction_output)
- direction_may_change = false;
+ if (desc->chip->direction_input && desc->chip->direction_output &&
+ direction_may_change) {
+ set_bit(FLAG_SYSFS_DIR, &desc->flags);
+ }
+
spin_unlock_irqrestore(&gpio_lock, flags);
offset = gpio_chip_hwgpio(desc);
@@ -567,27 +602,10 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
goto fail_unlock;
}
- if (direction_may_change) {
- status = device_create_file(dev, &dev_attr_direction);
- if (status)
- goto fail_unregister_device;
- }
-
- if (gpiod_to_irq(desc) >= 0 && (direction_may_change ||
- !test_bit(FLAG_IS_OUT, &desc->flags))) {
- status = device_create_file(dev, &dev_attr_edge);
- if (status)
- goto fail_remove_attr_direction;
- }
-
set_bit(FLAG_EXPORT, &desc->flags);
mutex_unlock(&sysfs_lock);
return 0;
-fail_remove_attr_direction:
- device_remove_file(dev, &dev_attr_direction);
-fail_unregister_device:
- device_unregister(dev);
fail_unlock:
mutex_unlock(&sysfs_lock);
gpiod_dbg(desc, "%s: status %d\n", __func__, status);
@@ -711,6 +729,7 @@ void gpiod_unexport(struct gpio_desc *desc)
dev = class_find_device(&gpio_class, NULL, desc, match_export);
if (dev) {
gpio_setup_irq(desc, dev, 0);
+ clear_bit(FLAG_SYSFS_DIR, &desc->flags);
clear_bit(FLAG_EXPORT, &desc->flags);
} else
status = -ENODEV;
@@ -719,8 +738,6 @@ void gpiod_unexport(struct gpio_desc *desc)
mutex_unlock(&sysfs_lock);
if (dev) {
- device_remove_file(dev, &dev_attr_edge);
- device_remove_file(dev, &dev_attr_direction);
device_unregister(dev);
put_device(dev);
}
diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h
index e3a52113a5410..550a5eafbd38c 100644
--- a/drivers/gpio/gpiolib.h
+++ b/drivers/gpio/gpiolib.h
@@ -77,6 +77,7 @@ struct gpio_desc {
#define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */
#define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */
#define FLAG_USED_AS_IRQ 9 /* GPIO is connected to an IRQ */
+#define FLAG_SYSFS_DIR 10 /* show sysfs direction attribute */
#define ID_SHIFT 16 /* add new flags before this one */
From 7b8792bbdffdff3abda704f89c6a45ea97afdc62 Mon Sep 17 00:00:00 2001
From: Hans Holmberg <hans.holmberg@intel.com>
Date: Fri, 9 Jan 2015 09:40:43 +0100
Subject: [PATCH 11/11] gpiolib: of: Correct error handling in
of_get_named_gpiod_flags
of_get_named_gpiod_flags fails with -EPROBE_DEFER in cases
where the gpio chip is available and the GPIO translation fails.
This causes drivers to be re-probed erroneusly, and hides the
real problem(i.e. the GPIO number being out of range).
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Hans Holmberg <hans.holmberg@intel.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/gpio/gpiolib-of.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index 604dbe60bdee1..08261f2b3a82a 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -45,8 +45,14 @@ static int of_gpiochip_find_and_xlate(struct gpio_chip *gc, void *data)
return false;
ret = gc->of_xlate(gc, &gg_data->gpiospec, gg_data->flags);
- if (ret < 0)
- return false;
+ if (ret < 0) {
+ /* We've found the gpio chip, but the translation failed.
+ * Return true to stop looking and return the translation
+ * error via out_gpio
+ */
+ gg_data->out_gpio = ERR_PTR(ret);
+ return true;
+ }
gg_data->out_gpio = gpiochip_get_desc(gc, ret);
return true;