[PATCH 6/9] gpiolib: use descriptors internally

From: Alexandre Courbot
Date: Sat Feb 02 2013 - 11:28:58 EST

Make sure gpiolib works internally with descriptors and (chip, offset)
pairs instead of using the global integer namespace. This prepares the
ground for the removal of the global gpio_desc[] array and the
introduction of the descriptor-based GPIO API.

Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxx>
---
drivers/gpio/gpiolib.c | 493 +++++++++++++++++++++++++++++++------------------
1 file changed, 317 insertions(+), 176 deletions(-)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index af4c350..82c40bd 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -78,6 +78,28 @@ static LIST_HEAD(gpio_chips);
static DEFINE_IDR(dirent_idr);
#endif

+/*
+ * Internal gpiod_* API using descriptors instead of the integer namespace.
+ * Most of this should eventually go public.
+ */
+static int gpiod_request(struct gpio_desc *desc, const char *label);
+static void gpiod_free(struct gpio_desc *desc);
+static int gpiod_direction_input(struct gpio_desc *desc);
+static int gpiod_direction_output(struct gpio_desc *desc, int value);
+static int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce);
+static int gpiod_get_value_cansleep(struct gpio_desc *desc);
+static void gpiod_set_value_cansleep(struct gpio_desc *desc, int value);
+static int gpiod_get_value(struct gpio_desc *desc);
+static void gpiod_set_value(struct gpio_desc *desc, int value);
+static int gpiod_cansleep(struct gpio_desc *desc);
+static int gpiod_to_irq(struct gpio_desc *desc);
+static int gpiod_export(struct gpio_desc *desc, bool direction_may_change);
+static int gpiod_export_link(struct device *dev, const char *name,
+ struct gpio_desc *desc);
+static int gpiod_sysfs_set_active_low(struct gpio_desc *desc, int value);
+static void gpiod_unexport(struct gpio_desc *desc);
+
+
static inline void desc_set_label(struct gpio_desc *d, const char *label)
{
#ifdef CONFIG_DEBUG_FS
@@ -85,6 +107,36 @@ static inline void desc_set_label(struct gpio_desc *d, const char *label)
#endif
}

+/*
+ * Return the GPIO number of the passed descriptor relative to its chip
+ */
+static int gpio_chip_hwgpio(const struct gpio_desc *desc)
+{
+ return (desc - &gpio_desc[0]) - desc->chip->base;
+}
+
+/**
+ * Convert a GPIO number to its descriptor
+ */
+static struct gpio_desc *gpio_to_desc(unsigned gpio)
+{
+ if (WARN(!gpio_is_valid(gpio), "invalid GPIO %d\n", gpio))
+ return NULL;
+ else
+ return &gpio_desc[gpio];
+}
+
+/**
+ * Convert a GPIO descriptor to the integer namespace.
+ * This should disappear in the future but is needed since we still
+ * use GPIO numbers for error messages and sysfs nodes
+ */
+static int desc_to_gpio(const struct gpio_desc *desc)
+{
+ return desc - &gpio_desc[0];
+}
+
+
/* Warn when drivers omit gpio_request() calls -- legal but ill-advised
* when setting direction, and otherwise illegal. Until board setup code
* and drivers use explicit requests everywhere (which won't happen when
@@ -96,10 +148,10 @@ static inline void desc_set_label(struct gpio_desc *d, const char *label)
* only "legal" in the sense that (old) code using it won't break yet,
* but instead only triggers a WARN() stack dump.
*/
-static int gpio_ensure_requested(struct gpio_desc *desc, unsigned offset)
+static int gpio_ensure_requested(struct gpio_desc *desc)
{
const struct gpio_chip *chip = desc->chip;
- const int gpio = chip->base + offset;
+ const int gpio = desc_to_gpio(desc);

if (WARN(test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0,
"autorequest GPIO-%d\n", gpio)) {
@@ -118,9 +170,14 @@ static int gpio_ensure_requested(struct gpio_desc *desc, unsigned offset)
}

/* caller holds gpio_lock *OR* gpio is marked as requested */
+static struct gpio_chip *gpiod_to_chip(struct gpio_desc *desc)
+{
+ return desc->chip;
+}
+
struct gpio_chip *gpio_to_chip(unsigned gpio)
{
- return gpio_desc[gpio].chip;
+ return gpiod_to_chip(gpio_to_desc(gpio));
}

/* dynamic allocation of GPIOs, e.g. on a hotplugged device */
@@ -148,19 +205,19 @@ static int gpiochip_find_base(int ngpio)
}

/* caller ensures gpio is valid and requested, chip->get_direction may sleep */
-static int gpio_get_direction(unsigned gpio)
+static int gpiod_get_direction(struct gpio_desc *desc)
{
struct gpio_chip *chip;
- struct gpio_desc *desc = &gpio_desc[gpio];
+ unsigned offset;
int status = -EINVAL;

- chip = gpio_to_chip(gpio);
- gpio -= chip->base;
+ chip = gpiod_to_chip(desc);
+ offset = gpio_chip_hwgpio(desc);

if (!chip->get_direction)
return status;

- status = chip->get_direction(chip, gpio);
+ status = chip->get_direction(chip, offset);
if (status > 0) {
/* GPIOF_DIR_IN, or other positive */
status = 1;
@@ -204,8 +261,7 @@ static DEFINE_MUTEX(sysfs_lock);
static ssize_t gpio_direction_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- const struct gpio_desc *desc = dev_get_drvdata(dev);
- unsigned gpio = desc - gpio_desc;
+ struct gpio_desc *desc = dev_get_drvdata(dev);
ssize_t status;

mutex_lock(&sysfs_lock);
@@ -213,7 +269,7 @@ static ssize_t gpio_direction_show(struct device *dev,
if (!test_bit(FLAG_EXPORT, &desc->flags))
status = -EIO;
else
- gpio_get_direction(gpio);
+ gpiod_get_direction(desc);
status = sprintf(buf, "%s\n",
test_bit(FLAG_IS_OUT, &desc->flags)
? "out" : "in");
@@ -225,8 +281,7 @@ static ssize_t gpio_direction_show(struct device *dev,
static ssize_t gpio_direction_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
- const struct gpio_desc *desc = dev_get_drvdata(dev);
- unsigned gpio = desc - gpio_desc;
+ struct gpio_desc *desc = dev_get_drvdata(dev);
ssize_t status;

mutex_lock(&sysfs_lock);
@@ -234,11 +289,11 @@ static ssize_t gpio_direction_store(struct device *dev,
if (!test_bit(FLAG_EXPORT, &desc->flags))
status = -EIO;
else if (sysfs_streq(buf, "high"))
- status = gpio_direction_output(gpio, 1);
+ status = gpiod_direction_output(desc, 1);
else if (sysfs_streq(buf, "out") || sysfs_streq(buf, "low"))
- status = gpio_direction_output(gpio, 0);
+ status = gpiod_direction_output(desc, 0);
else if (sysfs_streq(buf, "in"))
- status = gpio_direction_input(gpio);
+ status = gpiod_direction_input(desc);
else
status = -EINVAL;

@@ -252,8 +307,7 @@ static /* const */ DEVICE_ATTR(direction, 0644,
static ssize_t gpio_value_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- const struct gpio_desc *desc = dev_get_drvdata(dev);
- unsigned gpio = desc - gpio_desc;
+ struct gpio_desc *desc = dev_get_drvdata(dev);
ssize_t status;

mutex_lock(&sysfs_lock);
@@ -263,7 +317,7 @@ static ssize_t gpio_value_show(struct device *dev,
} else {
int value;

- value = !!gpio_get_value_cansleep(gpio);
+ value = !!gpiod_get_value_cansleep(desc);
if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
value = !value;

@@ -277,8 +331,7 @@ static ssize_t gpio_value_show(struct device *dev,
static ssize_t gpio_value_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
- const struct gpio_desc *desc = dev_get_drvdata(dev);
- unsigned gpio = desc - gpio_desc;
+ struct gpio_desc *desc = dev_get_drvdata(dev);
ssize_t status;

mutex_lock(&sysfs_lock);
@@ -294,7 +347,7 @@ static ssize_t gpio_value_store(struct device *dev,
if (status == 0) {
if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
value = !value;
- gpio_set_value_cansleep(gpio, value != 0);
+ gpiod_set_value_cansleep(desc, value != 0);
status = size;
}
}
@@ -324,7 +377,7 @@ static int gpio_setup_irq(struct gpio_desc *desc, struct device *dev,
if ((desc->flags & GPIO_TRIGGER_MASK) == gpio_flags)
return 0;

- irq = gpio_to_irq(desc - gpio_desc);
+ irq = gpiod_to_irq(desc);
if (irq < 0)
return -EIO;

@@ -594,29 +647,32 @@ static ssize_t export_store(struct class *class,
struct class_attribute *attr,
const char *buf, size_t len)
{
- long gpio;
- int status;
+ long gpio;
+ struct gpio_desc *desc;
+ int status;

status = strict_strtol(buf, 0, &gpio);
if (status < 0)
goto done;

+ desc = gpio_to_desc(gpio);
+
/* No extra locking here; FLAG_SYSFS just signifies that the
* request and export were done by on behalf of userspace, so
* they may be undone on its behalf too.
*/

- status = gpio_request(gpio, "sysfs");
+ status = gpiod_request(desc, "sysfs");
if (status < 0) {
if (status == -EPROBE_DEFER)
status = -ENODEV;
goto done;
}
- status = gpio_export(gpio, true);
+ status = gpiod_export(desc, true);
if (status < 0)
- gpio_free(gpio);
+ gpiod_free(desc);
else
- set_bit(FLAG_SYSFS, &gpio_desc[gpio].flags);
+ set_bit(FLAG_SYSFS, &desc->flags);

done:
if (status)
@@ -628,8 +684,9 @@ static ssize_t unexport_store(struct class *class,
struct class_attribute *attr,
const char *buf, size_t len)
{
- long gpio;
- int status;
+ long gpio;
+ struct gpio_desc *desc;
+ int status;

status = strict_strtol(buf, 0, &gpio);
if (status < 0)
@@ -637,17 +694,18 @@ static ssize_t unexport_store(struct class *class,

status = -EINVAL;

+ desc = gpio_to_desc(gpio);
/* reject bogus commands (gpio_unexport ignores them) */
- if (!gpio_is_valid(gpio))
+ if (!desc)
goto done;

/* No extra locking here; FLAG_SYSFS just signifies that the
* request and export were done by on behalf of userspace, so
* they may be undone on its behalf too.
*/
- if (test_and_clear_bit(FLAG_SYSFS, &gpio_desc[gpio].flags)) {
+ if (test_and_clear_bit(FLAG_SYSFS, &desc->flags)) {
status = 0;
- gpio_free(gpio);
+ gpiod_free(desc);
}
done:
if (status)
@@ -684,13 +742,13 @@ static struct class gpio_class = {
*
* Returns zero on success, else an error.
*/
-int gpio_export(unsigned gpio, bool direction_may_change)
+static int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
{
unsigned long flags;
- struct gpio_desc *desc;
int status;
const char *ioname = NULL;
struct device *dev;
+ int offset;

/* can't export until sysfs is available ... */
if (!gpio_class.p) {
@@ -698,20 +756,19 @@ int gpio_export(unsigned gpio, bool direction_may_change)
return -ENOENT;
}

- if (!gpio_is_valid(gpio)) {
- pr_debug("%s: gpio %d is not valid\n", __func__, gpio);
+ if (!desc) {
+ pr_debug("%s: invalid gpio descriptor\n", __func__);
return -EINVAL;
}

mutex_lock(&sysfs_lock);

spin_lock_irqsave(&gpio_lock, flags);
- desc = &gpio_desc[gpio];
if (!test_bit(FLAG_REQUESTED, &desc->flags) ||
test_bit(FLAG_EXPORT, &desc->flags)) {
spin_unlock_irqrestore(&gpio_lock, flags);
pr_debug("%s: gpio %d unavailable (requested=%d, exported=%d)\n",
- __func__, gpio,
+ __func__, desc_to_gpio(desc),
test_bit(FLAG_REQUESTED, &desc->flags),
test_bit(FLAG_EXPORT, &desc->flags));
status = -EPERM;
@@ -722,11 +779,13 @@ int gpio_export(unsigned gpio, bool direction_may_change)
direction_may_change = false;
spin_unlock_irqrestore(&gpio_lock, flags);

- if (desc->chip->names && desc->chip->names[gpio - desc->chip->base])
- ioname = desc->chip->names[gpio - desc->chip->base];
+ offset = gpio_chip_hwgpio(desc);
+ 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", gpio);
+ desc, ioname ? ioname : "gpio%u",
+ desc_to_gpio(desc));
if (IS_ERR(dev)) {
status = PTR_ERR(dev);
goto fail_unlock;
@@ -742,7 +801,7 @@ int gpio_export(unsigned gpio, bool direction_may_change)
goto fail_unregister_device;
}

- if (gpio_to_irq(gpio) >= 0 && (direction_may_change ||
+ 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)
@@ -757,9 +816,15 @@ fail_unregister_device:
device_unregister(dev);
fail_unlock:
mutex_unlock(&sysfs_lock);
- pr_debug("%s: gpio%d status %d\n", __func__, gpio, status);
+ pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc),
+ status);
return status;
}
+
+int gpio_export(unsigned gpio, bool direction_may_change)
+{
+ return gpiod_export(gpio_to_desc(gpio), direction_may_change);
+}
EXPORT_SYMBOL_GPL(gpio_export);

static int match_export(struct device *dev, void *data)
@@ -778,18 +843,16 @@ static int match_export(struct device *dev, void *data)
*
* Returns zero on success, else an error.
*/
-int gpio_export_link(struct device *dev, const char *name, unsigned gpio)
+static int gpiod_export_link(struct device *dev, const char *name,
+ struct gpio_desc *desc)
{
- struct gpio_desc *desc;
int status = -EINVAL;

- if (!gpio_is_valid(gpio))
+ if (!desc)
goto done;

mutex_lock(&sysfs_lock);

- desc = &gpio_desc[gpio];
-
if (test_bit(FLAG_EXPORT, &desc->flags)) {
struct device *tdev;

@@ -806,12 +869,17 @@ int gpio_export_link(struct device *dev, const char *name, unsigned gpio)

done:
if (status)
- pr_debug("%s: gpio%d status %d\n", __func__, gpio, status);
+ pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc),
+ status);

return status;
}
-EXPORT_SYMBOL_GPL(gpio_export_link);

+int gpio_export_link(struct device *dev, const char *name, unsigned gpio)
+{
+ return gpiod_export_link(dev, name, gpio_to_desc(gpio));
+}
+EXPORT_SYMBOL_GPL(gpio_export_link);

/**
* gpio_sysfs_set_active_low - set the polarity of gpio sysfs value
@@ -825,19 +893,16 @@ EXPORT_SYMBOL_GPL(gpio_export_link);
*
* Returns zero on success, else an error.
*/
-int gpio_sysfs_set_active_low(unsigned gpio, int value)
+static int gpiod_sysfs_set_active_low(struct gpio_desc *desc, int value)
{
- struct gpio_desc *desc;
struct device *dev = NULL;
int status = -EINVAL;

- if (!gpio_is_valid(gpio))
+ if (!desc)
goto done;

mutex_lock(&sysfs_lock);

- desc = &gpio_desc[gpio];
-
if (test_bit(FLAG_EXPORT, &desc->flags)) {
dev = class_find_device(&gpio_class, NULL, desc, match_export);
if (dev == NULL) {
@@ -853,10 +918,16 @@ unlock:

done:
if (status)
- pr_debug("%s: gpio%d status %d\n", __func__, gpio, status);
+ pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc),
+ status);

return status;
}
+
+int gpio_sysfs_set_active_low(unsigned gpio, int value)
+{
+ return gpiod_sysfs_set_active_low(gpio_to_desc(gpio), value);
+}
EXPORT_SYMBOL_GPL(gpio_sysfs_set_active_low);

/**
@@ -865,21 +936,18 @@ EXPORT_SYMBOL_GPL(gpio_sysfs_set_active_low);
*
* This is implicit on gpio_free().
*/
-void gpio_unexport(unsigned gpio)
+static void gpiod_unexport(struct gpio_desc *desc)
{
- struct gpio_desc *desc;
int status = 0;
struct device *dev = NULL;

- if (!gpio_is_valid(gpio)) {
+ if (!desc) {
status = -EINVAL;
goto done;
}

mutex_lock(&sysfs_lock);

- desc = &gpio_desc[gpio];
-
if (test_bit(FLAG_EXPORT, &desc->flags)) {

dev = class_find_device(&gpio_class, NULL, desc, match_export);
@@ -891,13 +959,20 @@ void gpio_unexport(unsigned gpio)
}

mutex_unlock(&sysfs_lock);
+
if (dev) {
device_unregister(dev);
put_device(dev);
}
done:
if (status)
- pr_debug("%s: gpio%d status %d\n", __func__, gpio, status);
+ pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc),
+ status);
+}
+
+void gpio_unexport(unsigned gpio)
+{
+ gpiod_unexport(gpio_to_desc(gpio));
}
EXPORT_SYMBOL_GPL(gpio_unexport);

@@ -1281,20 +1356,18 @@ EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
* on each other, and help provide better diagnostics in debugfs.
* They're called even less than the "set direction" calls.
*/
-int gpio_request(unsigned gpio, const char *label)
+static int gpiod_request(struct gpio_desc *desc, const char *label)
{
- struct gpio_desc *desc;
struct gpio_chip *chip;
int status = -EPROBE_DEFER;
unsigned long flags;

spin_lock_irqsave(&gpio_lock, flags);

- if (!gpio_is_valid(gpio)) {
+ if (!desc) {
status = -EINVAL;
goto done;
}
- desc = &gpio_desc[gpio];
chip = desc->chip;
if (chip == NULL)
goto done;
@@ -1318,7 +1391,7 @@ int gpio_request(unsigned gpio, const char *label)
if (chip->request) {
/* chip->request may sleep */
spin_unlock_irqrestore(&gpio_lock, flags);
- status = chip->request(chip, gpio - chip->base);
+ status = chip->request(chip, gpio_chip_hwgpio(desc));
spin_lock_irqsave(&gpio_lock, flags);

if (status < 0) {
@@ -1331,42 +1404,46 @@ int gpio_request(unsigned gpio, const char *label)
if (chip->get_direction) {
/* chip->get_direction may sleep */
spin_unlock_irqrestore(&gpio_lock, flags);
- gpio_get_direction(gpio);
+ gpiod_get_direction(desc);
spin_lock_irqsave(&gpio_lock, flags);
}
done:
if (status)
- pr_debug("gpio_request: gpio-%d (%s) status %d\n",
- gpio, label ? : "?", status);
+ pr_debug("_gpio_request: gpio-%d (%s) status %d\n",
+ desc ? desc_to_gpio(desc) : -1,
+ label ? : "?", status);
spin_unlock_irqrestore(&gpio_lock, flags);
return status;
}
+
+int gpio_request(unsigned gpio, const char *label)
+{
+ return gpiod_request(gpio_to_desc(gpio), label);
+}
EXPORT_SYMBOL_GPL(gpio_request);

-void gpio_free(unsigned gpio)
+static void gpiod_free(struct gpio_desc *desc)
{
unsigned long flags;
- struct gpio_desc *desc;
struct gpio_chip *chip;

might_sleep();

- if (!gpio_is_valid(gpio)) {
+ if (!desc) {
WARN_ON(extra_checks);
return;
}

- gpio_unexport(gpio);
+ gpiod_unexport(desc);

spin_lock_irqsave(&gpio_lock, flags);

- desc = &gpio_desc[gpio];
chip = desc->chip;
if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
if (chip->free) {
spin_unlock_irqrestore(&gpio_lock, flags);
might_sleep_if(chip->can_sleep);
- chip->free(chip, gpio - chip->base);
+ chip->free(chip, gpio_chip_hwgpio(desc));
spin_lock_irqsave(&gpio_lock, flags);
}
desc_set_label(desc, NULL);
@@ -1380,6 +1457,11 @@ void gpio_free(unsigned gpio)

spin_unlock_irqrestore(&gpio_lock, flags);
}
+
+void gpio_free(unsigned gpio)
+{
+ gpiod_free(gpio_to_desc(gpio));
+}
EXPORT_SYMBOL_GPL(gpio_free);

/**
@@ -1390,29 +1472,32 @@ EXPORT_SYMBOL_GPL(gpio_free);
*/
int gpio_request_one(unsigned gpio, unsigned long flags, const char *label)
{
+ struct gpio_desc *desc;
int err;

- err = gpio_request(gpio, label);
+ desc = gpio_to_desc(gpio);
+
+ err = gpiod_request(desc, label);
if (err)
return err;

if (flags & GPIOF_OPEN_DRAIN)
- set_bit(FLAG_OPEN_DRAIN, &gpio_desc[gpio].flags);
+ set_bit(FLAG_OPEN_DRAIN, &desc->flags);

if (flags & GPIOF_OPEN_SOURCE)
- set_bit(FLAG_OPEN_SOURCE, &gpio_desc[gpio].flags);
+ set_bit(FLAG_OPEN_SOURCE, &desc->flags);

if (flags & GPIOF_DIR_IN)
- err = gpio_direction_input(gpio);
+ err = gpiod_direction_input(desc);
else
- err = gpio_direction_output(gpio,
+ err = gpiod_direction_output(desc,
(flags & GPIOF_INIT_HIGH) ? 1 : 0);

if (err)
goto free_gpio;

if (flags & GPIOF_EXPORT) {
- err = gpio_export(gpio, flags & GPIOF_EXPORT_CHANGEABLE);
+ err = gpiod_export(desc, flags & GPIOF_EXPORT_CHANGEABLE);
if (err)
goto free_gpio;
}
@@ -1420,7 +1505,7 @@ int gpio_request_one(unsigned gpio, unsigned long flags, const char *label)
return 0;

free_gpio:
- gpio_free(gpio);
+ gpiod_free(desc);
return err;
}
EXPORT_SYMBOL_GPL(gpio_request_one);
@@ -1476,13 +1561,14 @@ EXPORT_SYMBOL_GPL(gpio_free_array);
const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset)
{
unsigned gpio = chip->base + offset;
+ struct gpio_desc *desc = &gpio_desc[gpio];

- if (!gpio_is_valid(gpio) || gpio_desc[gpio].chip != chip)
+ if (!gpio_is_valid(gpio) || desc->chip != chip)
return NULL;
- if (test_bit(FLAG_REQUESTED, &gpio_desc[gpio].flags) == 0)
+ if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
return NULL;
#ifdef CONFIG_DEBUG_FS
- return gpio_desc[gpio].label;
+ return desc->label;
#else
return "?";
#endif
@@ -1499,24 +1585,21 @@ EXPORT_SYMBOL_GPL(gpiochip_is_requested);
* rely on gpio_request() having been called beforehand.
*/

-int gpio_direction_input(unsigned gpio)
+static int gpiod_direction_input(struct gpio_desc *desc)
{
unsigned long flags;
struct gpio_chip *chip;
- struct gpio_desc *desc = &gpio_desc[gpio];
int status = -EINVAL;
+ int offset;

spin_lock_irqsave(&gpio_lock, flags);

- if (!gpio_is_valid(gpio))
+ if (!desc)
goto fail;
chip = desc->chip;
if (!chip || !chip->get || !chip->direction_input)
goto fail;
- gpio -= chip->base;
- if (gpio >= chip->ngpio)
- goto fail;
- status = gpio_ensure_requested(desc, gpio);
+ status = gpio_ensure_requested(desc);
if (status < 0)
goto fail;

@@ -1526,11 +1609,12 @@ int gpio_direction_input(unsigned gpio)

might_sleep_if(chip->can_sleep);

+ offset = gpio_chip_hwgpio(desc);
if (status) {
- status = chip->request(chip, gpio);
+ status = chip->request(chip, offset);
if (status < 0) {
pr_debug("GPIO-%d: chip request fail, %d\n",
- chip->base + gpio, status);
+ desc_to_gpio(desc), status);
/* and it's not available to anyone else ...
* gpio_request() is the fully clean solution.
*/
@@ -1538,48 +1622,54 @@ int gpio_direction_input(unsigned gpio)
}
}

- status = chip->direction_input(chip, gpio);
+ status = chip->direction_input(chip, offset);
if (status == 0)
clear_bit(FLAG_IS_OUT, &desc->flags);

- trace_gpio_direction(chip->base + gpio, 1, status);
+ trace_gpio_direction(desc_to_gpio(desc), 1, status);
lose:
return status;
fail:
spin_unlock_irqrestore(&gpio_lock, flags);
- if (status)
+ if (status) {
+ int gpio = -1;
+ if (desc)
+ gpio = desc_to_gpio(desc);
pr_debug("%s: gpio-%d status %d\n",
__func__, gpio, status);
+ }
return status;
}
+
+int gpio_direction_input(unsigned gpio)
+{
+ return gpiod_direction_input(gpio_to_desc(gpio));
+}
EXPORT_SYMBOL_GPL(gpio_direction_input);

-int gpio_direction_output(unsigned gpio, int value)
+static int gpiod_direction_output(struct gpio_desc *desc, int value)
{
unsigned long flags;
struct gpio_chip *chip;
- struct gpio_desc *desc = &gpio_desc[gpio];
int status = -EINVAL;
+ int offset;

/* Open drain pin should not be driven to 1 */
if (value && test_bit(FLAG_OPEN_DRAIN, &desc->flags))
- return gpio_direction_input(gpio);
+ return gpiod_direction_input(desc);

/* Open source pin should not be driven to 0 */
if (!value && test_bit(FLAG_OPEN_SOURCE, &desc->flags))
- return gpio_direction_input(gpio);
+ return gpiod_direction_input(desc);

spin_lock_irqsave(&gpio_lock, flags);

- if (!gpio_is_valid(gpio))
+ if (!desc)
goto fail;
chip = desc->chip;
if (!chip || !chip->set || !chip->direction_output)
goto fail;
- gpio -= chip->base;
- if (gpio >= chip->ngpio)
- goto fail;
- status = gpio_ensure_requested(desc, gpio);
+ status = gpio_ensure_requested(desc);
if (status < 0)
goto fail;

@@ -1589,11 +1679,12 @@ int gpio_direction_output(unsigned gpio, int value)

might_sleep_if(chip->can_sleep);

+ offset = gpio_chip_hwgpio(desc);
if (status) {
- status = chip->request(chip, gpio);
+ status = chip->request(chip, offset);
if (status < 0) {
pr_debug("GPIO-%d: chip request fail, %d\n",
- chip->base + gpio, status);
+ desc_to_gpio(desc), status);
/* and it's not available to anyone else ...
* gpio_request() is the fully clean solution.
*/
@@ -1601,20 +1692,29 @@ int gpio_direction_output(unsigned gpio, int value)
}
}

- status = chip->direction_output(chip, gpio, value);
+ status = chip->direction_output(chip, offset, value);
if (status == 0)
set_bit(FLAG_IS_OUT, &desc->flags);
- trace_gpio_value(chip->base + gpio, 0, value);
- trace_gpio_direction(chip->base + gpio, 0, status);
+ trace_gpio_value(desc_to_gpio(desc), 0, value);
+ trace_gpio_direction(desc_to_gpio(desc), 0, status);
lose:
return status;
fail:
spin_unlock_irqrestore(&gpio_lock, flags);
- if (status)
+ if (status) {
+ int gpio = -1;
+ if (desc)
+ gpio = desc_to_gpio(desc);
pr_debug("%s: gpio-%d status %d\n",
__func__, gpio, status);
+ }
return status;
}
+
+int gpio_direction_output(unsigned gpio, int value)
+{
+ return gpiod_direction_output(gpio_to_desc(gpio), value);
+}
EXPORT_SYMBOL_GPL(gpio_direction_output);

/**
@@ -1622,24 +1722,22 @@ EXPORT_SYMBOL_GPL(gpio_direction_output);
* @gpio: the gpio to set debounce time
* @debounce: debounce time is microseconds
*/
-int gpio_set_debounce(unsigned gpio, unsigned debounce)
+static int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
{
unsigned long flags;
struct gpio_chip *chip;
- struct gpio_desc *desc = &gpio_desc[gpio];
int status = -EINVAL;
+ int offset;

spin_lock_irqsave(&gpio_lock, flags);

- if (!gpio_is_valid(gpio))
+ if (!desc)
goto fail;
chip = desc->chip;
if (!chip || !chip->set || !chip->set_debounce)
goto fail;
- gpio -= chip->base;
- if (gpio >= chip->ngpio)
- goto fail;
- status = gpio_ensure_requested(desc, gpio);
+
+ status = gpio_ensure_requested(desc);
if (status < 0)
goto fail;

@@ -1649,16 +1747,26 @@ int gpio_set_debounce(unsigned gpio, unsigned debounce)

might_sleep_if(chip->can_sleep);

- return chip->set_debounce(chip, gpio, debounce);
+ offset = gpio_chip_hwgpio(desc);
+ return chip->set_debounce(chip, offset, debounce);

fail:
spin_unlock_irqrestore(&gpio_lock, flags);
- if (status)
+ if (status) {
+ int gpio = -1;
+ if (desc)
+ gpio = desc_to_gpio(desc);
pr_debug("%s: gpio-%d status %d\n",
__func__, gpio, status);
+ }

return status;
}
+
+int gpio_set_debounce(unsigned gpio, unsigned debounce)
+{
+ return gpiod_set_debounce(gpio_to_desc(gpio), debounce);
+}
EXPORT_SYMBOL_GPL(gpio_set_debounce);

/* I/O calls are only valid after configuration completed; the relevant
@@ -1692,18 +1800,25 @@ EXPORT_SYMBOL_GPL(gpio_set_debounce);
* It returns the zero or nonzero value provided by the associated
* gpio_chip.get() method; or zero if no such method is provided.
*/
-int __gpio_get_value(unsigned gpio)
+static int gpiod_get_value(struct gpio_desc *desc)
{
struct gpio_chip *chip;
int value;
+ int offset;

- chip = gpio_to_chip(gpio);
+ chip = desc->chip;
+ offset = gpio_chip_hwgpio(desc);
/* Should be using gpio_get_value_cansleep() */
WARN_ON(chip->can_sleep);
- value = chip->get ? chip->get(chip, gpio - chip->base) : 0;
- trace_gpio_value(gpio, 1, value);
+ value = chip->get ? chip->get(chip, offset) : 0;
+ trace_gpio_value(desc_to_gpio(desc), 1, value);
return value;
}
+
+int __gpio_get_value(unsigned gpio)
+{
+ return gpiod_get_value(gpio_to_desc(gpio));
+}
EXPORT_SYMBOL_GPL(__gpio_get_value);

/*
@@ -1712,23 +1827,25 @@ EXPORT_SYMBOL_GPL(__gpio_get_value);
* @chip: Gpio chip.
* @value: Non-zero for setting it HIGH otherise it will set to LOW.
*/
-static void _gpio_set_open_drain_value(unsigned gpio,
- struct gpio_chip *chip, int value)
+static void _gpio_set_open_drain_value(struct gpio_desc *desc, int value)
{
int err = 0;
+ struct gpio_chip *chip = desc->chip;
+ int offset = gpio_chip_hwgpio(desc);
+
if (value) {
- err = chip->direction_input(chip, gpio - chip->base);
+ err = chip->direction_input(chip, offset);
if (!err)
- clear_bit(FLAG_IS_OUT, &gpio_desc[gpio].flags);
+ clear_bit(FLAG_IS_OUT, &desc->flags);
} else {
- err = chip->direction_output(chip, gpio - chip->base, 0);
+ err = chip->direction_output(chip, offset, 0);
if (!err)
- set_bit(FLAG_IS_OUT, &gpio_desc[gpio].flags);
+ set_bit(FLAG_IS_OUT, &desc->flags);
}
- trace_gpio_direction(gpio, value, err);
+ trace_gpio_direction(desc_to_gpio(desc), value, err);
if (err < 0)
pr_err("%s: Error in set_value for open drain gpio%d err %d\n",
- __func__, gpio, err);
+ __func__, desc_to_gpio(desc), err);
}

/*
@@ -1737,26 +1854,27 @@ static void _gpio_set_open_drain_value(unsigned gpio,
* @chip: Gpio chip.
* @value: Non-zero for setting it HIGH otherise it will set to LOW.
*/
-static void _gpio_set_open_source_value(unsigned gpio,
- struct gpio_chip *chip, int value)
+static void _gpio_set_open_source_value(struct gpio_desc *desc, int value)
{
int err = 0;
+ struct gpio_chip *chip = desc->chip;
+ int offset = gpio_chip_hwgpio(desc);
+
if (value) {
- err = chip->direction_output(chip, gpio - chip->base, 1);
+ err = chip->direction_output(chip, offset, 1);
if (!err)
- set_bit(FLAG_IS_OUT, &gpio_desc[gpio].flags);
+ set_bit(FLAG_IS_OUT, &desc->flags);
} else {
- err = chip->direction_input(chip, gpio - chip->base);
+ err = chip->direction_input(chip, offset);
if (!err)
- clear_bit(FLAG_IS_OUT, &gpio_desc[gpio].flags);
+ clear_bit(FLAG_IS_OUT, &desc->flags);
}
- trace_gpio_direction(gpio, !value, err);
+ trace_gpio_direction(desc_to_gpio(desc), !value, err);
if (err < 0)
pr_err("%s: Error in set_value for open source gpio%d err %d\n",
- __func__, gpio, err);
+ __func__, desc_to_gpio(desc), err);
}

-
/**
* __gpio_set_value() - assign a gpio's value
* @gpio: gpio whose value will be assigned
@@ -1766,20 +1884,25 @@ static void _gpio_set_open_source_value(unsigned gpio,
* This is used directly or indirectly to implement gpio_set_value().
* It invokes the associated gpio_chip.set() method.
*/
-void __gpio_set_value(unsigned gpio, int value)
+static void gpiod_set_value(struct gpio_desc *desc, int value)
{
struct gpio_chip *chip;

- chip = gpio_to_chip(gpio);
+ chip = desc->chip;
/* Should be using gpio_set_value_cansleep() */
WARN_ON(chip->can_sleep);
- trace_gpio_value(gpio, 0, value);
- if (test_bit(FLAG_OPEN_DRAIN, &gpio_desc[gpio].flags))
- _gpio_set_open_drain_value(gpio, chip, value);
- else if (test_bit(FLAG_OPEN_SOURCE, &gpio_desc[gpio].flags))
- _gpio_set_open_source_value(gpio, chip, value);
+ trace_gpio_value(desc_to_gpio(desc), 0, value);
+ if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
+ _gpio_set_open_drain_value(desc, value);
+ else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
+ _gpio_set_open_source_value(desc, value);
else
- chip->set(chip, gpio - chip->base, value);
+ chip->set(chip, gpio_chip_hwgpio(desc), value);
+}
+
+void __gpio_set_value(unsigned gpio, int value)
+{
+ return gpiod_set_value(gpio_to_desc(gpio), value);
}
EXPORT_SYMBOL_GPL(__gpio_set_value);

@@ -1791,14 +1914,15 @@ EXPORT_SYMBOL_GPL(__gpio_set_value);
* This is used directly or indirectly to implement gpio_cansleep(). It
* returns nonzero if access reading or writing the GPIO value can sleep.
*/
-int __gpio_cansleep(unsigned gpio)
+static int gpiod_cansleep(struct gpio_desc *desc)
{
- struct gpio_chip *chip;
-
/* only call this on GPIOs that are valid! */
- chip = gpio_to_chip(gpio);
+ return desc->chip->can_sleep;
+}

- return chip->can_sleep;
+int __gpio_cansleep(unsigned gpio)
+{
+ return gpiod_cansleep(gpio_to_desc(gpio));
}
EXPORT_SYMBOL_GPL(__gpio_cansleep);

@@ -1811,50 +1935,67 @@ EXPORT_SYMBOL_GPL(__gpio_cansleep);
* It returns the number of the IRQ signaled by this (input) GPIO,
* or a negative errno.
*/
-int __gpio_to_irq(unsigned gpio)
+static int gpiod_to_irq(struct gpio_desc *desc)
{
struct gpio_chip *chip;
+ int offset;

- chip = gpio_to_chip(gpio);
- return chip->to_irq ? chip->to_irq(chip, gpio - chip->base) : -ENXIO;
+ chip = desc->chip;
+ offset = gpio_chip_hwgpio(desc);
+ return chip->to_irq ? chip->to_irq(chip, offset) : -ENXIO;
}
-EXPORT_SYMBOL_GPL(__gpio_to_irq);

+int __gpio_to_irq(unsigned gpio)
+{
+ return gpiod_to_irq(gpio_to_desc(gpio));
+}
+EXPORT_SYMBOL_GPL(__gpio_to_irq);


/* There's no value in making it easy to inline GPIO calls that may sleep.
* Common examples include ones connected to I2C or SPI chips.
*/

-int gpio_get_value_cansleep(unsigned gpio)
+static int gpiod_get_value_cansleep(struct gpio_desc *desc)
{
struct gpio_chip *chip;
int value;
+ int offset;

might_sleep_if(extra_checks);
- chip = gpio_to_chip(gpio);
- value = chip->get ? chip->get(chip, gpio - chip->base) : 0;
- trace_gpio_value(gpio, 1, value);
+ chip = desc->chip;
+ offset = gpio_chip_hwgpio(desc);
+ value = chip->get ? chip->get(chip, offset) : 0;
+ trace_gpio_value(desc_to_gpio(desc), 1, value);
return value;
}
+
+int gpio_get_value_cansleep(unsigned gpio)
+{
+ return gpiod_get_value_cansleep(gpio_to_desc(gpio));
+}
EXPORT_SYMBOL_GPL(gpio_get_value_cansleep);

-void gpio_set_value_cansleep(unsigned gpio, int value)
+static void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
{
struct gpio_chip *chip;

might_sleep_if(extra_checks);
- chip = gpio_to_chip(gpio);
- trace_gpio_value(gpio, 0, value);
- if (test_bit(FLAG_OPEN_DRAIN, &gpio_desc[gpio].flags))
- _gpio_set_open_drain_value(gpio, chip, value);
- else if (test_bit(FLAG_OPEN_SOURCE, &gpio_desc[gpio].flags))
- _gpio_set_open_source_value(gpio, chip, value);
+ chip = desc->chip;
+ trace_gpio_value(desc_to_gpio(desc), 0, value);
+ if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
+ _gpio_set_open_drain_value(desc, value);
+ else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
+ _gpio_set_open_source_value(desc, value);
else
- chip->set(chip, gpio - chip->base, value);
+ chip->set(chip, gpio_chip_hwgpio(desc), value);
}
-EXPORT_SYMBOL_GPL(gpio_set_value_cansleep);

+void gpio_set_value_cansleep(unsigned gpio, int value)
+{
+ return gpiod_set_value_cansleep(gpio_to_desc(gpio), value);
+}
+EXPORT_SYMBOL_GPL(gpio_set_value_cansleep);

#ifdef CONFIG_DEBUG_FS

@@ -1869,7 +2010,7 @@ static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip)
if (!test_bit(FLAG_REQUESTED, &gdesc->flags))
continue;

- gpio_get_direction(gpio);
+ gpiod_get_direction(gdesc);
is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
seq_printf(s, " gpio-%-3d (%-20.20s) %s %s",
gpio, gdesc->label,
--
1.8.1.1

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