summaryrefslogtreecommitdiff
path: root/drivers/gpio
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/gpio')
-rw-r--r--drivers/gpio/gpiolib.c115
-rw-r--r--drivers/gpio/max7301.c24
-rw-r--r--drivers/gpio/max732x.c5
-rw-r--r--drivers/gpio/mcp23s08.c5
-rw-r--r--drivers/gpio/pca953x.c5
-rw-r--r--drivers/gpio/pcf857x.c5
6 files changed, 128 insertions, 31 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 572d372899d3..faa1cc66e9cf 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -67,17 +67,28 @@ static inline void desc_set_label(struct gpio_desc *d, const char *label)
* when setting direction, and otherwise illegal. Until board setup code
* and drivers use explicit requests everywhere (which won't happen when
* those calls have no teeth) we can't avoid autorequesting. This nag
- * message should motivate switching to explicit requests...
+ * message should motivate switching to explicit requests... so should
+ * the weaker cleanup after faults, compared to gpio_request().
*/
-static void gpio_ensure_requested(struct gpio_desc *desc)
+static int gpio_ensure_requested(struct gpio_desc *desc, unsigned offset)
{
if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
- pr_warning("GPIO-%d autorequested\n", (int)(desc - gpio_desc));
+ struct gpio_chip *chip = desc->chip;
+ int gpio = chip->base + offset;
+
+ if (!try_module_get(chip->owner)) {
+ pr_err("GPIO-%d: module can't be gotten \n", gpio);
+ clear_bit(FLAG_REQUESTED, &desc->flags);
+ /* lose */
+ return -EIO;
+ }
+ pr_warning("GPIO-%d autorequested\n", gpio);
desc_set_label(desc, "[auto]");
- if (!try_module_get(desc->chip->owner))
- pr_err("GPIO-%d: module can't be gotten \n",
- (int)(desc - gpio_desc));
+ /* caller must chip->request() w/o spinlock */
+ if (chip->request)
+ return 1;
}
+ return 0;
}
/* caller holds gpio_lock *OR* gpio is marked as requested */
@@ -237,7 +248,7 @@ static ssize_t gpio_value_show(struct device *dev,
if (!test_bit(FLAG_EXPORT, &desc->flags))
status = -EIO;
else
- status = sprintf(buf, "%d\n", gpio_get_value_cansleep(gpio));
+ status = sprintf(buf, "%d\n", !!gpio_get_value_cansleep(gpio));
mutex_unlock(&sysfs_lock);
return status;
@@ -752,6 +763,7 @@ EXPORT_SYMBOL_GPL(gpiochip_remove);
int gpio_request(unsigned gpio, const char *label)
{
struct gpio_desc *desc;
+ struct gpio_chip *chip;
int status = -EINVAL;
unsigned long flags;
@@ -760,14 +772,15 @@ int gpio_request(unsigned gpio, const char *label)
if (!gpio_is_valid(gpio))
goto done;
desc = &gpio_desc[gpio];
- if (desc->chip == NULL)
+ chip = desc->chip;
+ if (chip == NULL)
goto done;
- if (!try_module_get(desc->chip->owner))
+ if (!try_module_get(chip->owner))
goto done;
/* NOTE: gpio_request() can be called in early boot,
- * before IRQs are enabled.
+ * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
*/
if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
@@ -775,7 +788,20 @@ int gpio_request(unsigned gpio, const char *label)
status = 0;
} else {
status = -EBUSY;
- module_put(desc->chip->owner);
+ module_put(chip->owner);
+ }
+
+ if (chip->request) {
+ /* chip->request may sleep */
+ spin_unlock_irqrestore(&gpio_lock, flags);
+ status = chip->request(chip, gpio - chip->base);
+ spin_lock_irqsave(&gpio_lock, flags);
+
+ if (status < 0) {
+ desc_set_label(desc, NULL);
+ module_put(chip->owner);
+ clear_bit(FLAG_REQUESTED, &desc->flags);
+ }
}
done:
@@ -791,6 +817,9 @@ void gpio_free(unsigned gpio)
{
unsigned long flags;
struct gpio_desc *desc;
+ struct gpio_chip *chip;
+
+ might_sleep();
if (!gpio_is_valid(gpio)) {
WARN_ON(extra_checks);
@@ -802,9 +831,17 @@ void gpio_free(unsigned gpio)
spin_lock_irqsave(&gpio_lock, flags);
desc = &gpio_desc[gpio];
- if (desc->chip && test_and_clear_bit(FLAG_REQUESTED, &desc->flags)) {
+ chip = desc->chip;
+ if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
+ if (chip->free) {
+ spin_unlock_irqrestore(&gpio_lock, flags);
+ might_sleep_if(extra_checks && chip->can_sleep);
+ chip->free(chip, gpio - chip->base);
+ spin_lock_irqsave(&gpio_lock, flags);
+ }
desc_set_label(desc, NULL);
module_put(desc->chip->owner);
+ clear_bit(FLAG_REQUESTED, &desc->flags);
} else
WARN_ON(extra_checks);
@@ -869,7 +906,9 @@ int gpio_direction_input(unsigned gpio)
gpio -= chip->base;
if (gpio >= chip->ngpio)
goto fail;
- gpio_ensure_requested(desc);
+ status = gpio_ensure_requested(desc, gpio);
+ if (status < 0)
+ goto fail;
/* now we know the gpio is valid and chip won't vanish */
@@ -877,9 +916,22 @@ int gpio_direction_input(unsigned gpio)
might_sleep_if(extra_checks && chip->can_sleep);
+ if (status) {
+ status = chip->request(chip, gpio);
+ if (status < 0) {
+ pr_debug("GPIO-%d: chip request fail, %d\n",
+ chip->base + gpio, status);
+ /* and it's not available to anyone else ...
+ * gpio_request() is the fully clean solution.
+ */
+ goto lose;
+ }
+ }
+
status = chip->direction_input(chip, gpio);
if (status == 0)
clear_bit(FLAG_IS_OUT, &desc->flags);
+lose:
return status;
fail:
spin_unlock_irqrestore(&gpio_lock, flags);
@@ -907,7 +959,9 @@ int gpio_direction_output(unsigned gpio, int value)
gpio -= chip->base;
if (gpio >= chip->ngpio)
goto fail;
- gpio_ensure_requested(desc);
+ status = gpio_ensure_requested(desc, gpio);
+ if (status < 0)
+ goto fail;
/* now we know the gpio is valid and chip won't vanish */
@@ -915,9 +969,22 @@ int gpio_direction_output(unsigned gpio, int value)
might_sleep_if(extra_checks && chip->can_sleep);
+ if (status) {
+ status = chip->request(chip, gpio);
+ if (status < 0) {
+ pr_debug("GPIO-%d: chip request fail, %d\n",
+ chip->base + gpio, status);
+ /* and it's not available to anyone else ...
+ * gpio_request() is the fully clean solution.
+ */
+ goto lose;
+ }
+ }
+
status = chip->direction_output(chip, gpio, value);
if (status == 0)
set_bit(FLAG_IS_OUT, &desc->flags);
+lose:
return status;
fail:
spin_unlock_irqrestore(&gpio_lock, flags);
@@ -1008,6 +1075,24 @@ int __gpio_cansleep(unsigned gpio)
}
EXPORT_SYMBOL_GPL(__gpio_cansleep);
+/**
+ * __gpio_to_irq() - return the IRQ corresponding to a GPIO
+ * @gpio: gpio whose IRQ will be returned (already requested)
+ * Context: any
+ *
+ * This is used directly or indirectly to implement gpio_to_irq().
+ * It returns the number of the IRQ signaled by this (input) GPIO,
+ * or a negative errno.
+ */
+int __gpio_to_irq(unsigned gpio)
+{
+ struct gpio_chip *chip;
+
+ chip = gpio_to_chip(gpio);
+ return chip->to_irq ? chip->to_irq(chip, gpio - chip->base) : -ENXIO;
+}
+EXPORT_SYMBOL_GPL(__gpio_to_irq);
+
/* There's no value in making it easy to inline GPIO calls that may sleep.
@@ -1020,7 +1105,7 @@ int gpio_get_value_cansleep(unsigned gpio)
might_sleep_if(extra_checks);
chip = gpio_to_chip(gpio);
- return chip->get(chip, gpio - chip->base);
+ return chip->get ? chip->get(chip, gpio - chip->base) : 0;
}
EXPORT_SYMBOL_GPL(gpio_get_value_cansleep);
diff --git a/drivers/gpio/max7301.c b/drivers/gpio/max7301.c
index 39c795ad8312..8b24d784db93 100644
--- a/drivers/gpio/max7301.c
+++ b/drivers/gpio/max7301.c
@@ -255,10 +255,6 @@ static int __devinit max7301_probe(struct spi_device *spi)
ts->chip.dev = &spi->dev;
ts->chip.owner = THIS_MODULE;
- ret = gpiochip_add(&ts->chip);
- if (ret)
- goto exit_destroy;
-
/*
* tristate all pins in hardware and cache the
* register values for later use.
@@ -269,17 +265,19 @@ static int __devinit max7301_probe(struct spi_device *spi)
max7301_write(spi, 0x08 + i, 0xAA);
ts->port_config[i] = 0xAA;
for (j = 0; j < 4; j++) {
- int idx = ts->chip.base + (i - 1) * 4 + j;
- ret = gpio_direction_input(idx);
+ int offset = (i - 1) * 4 + j;
+ ret = max7301_direction_input(&ts->chip, offset);
if (ret)
- goto exit_remove;
- gpio_free(idx);
+ goto exit_destroy;
}
}
+
+ ret = gpiochip_add(&ts->chip);
+ if (ret)
+ goto exit_destroy;
+
return ret;
-exit_remove:
- gpiochip_remove(&ts->chip);
exit_destroy:
dev_set_drvdata(&spi->dev, NULL);
mutex_destroy(&ts->lock);
@@ -325,13 +323,15 @@ static int __init max7301_init(void)
{
return spi_register_driver(&max7301_driver);
}
+/* register after spi postcore initcall and before
+ * subsys initcalls that may rely on these GPIOs
+ */
+subsys_initcall(max7301_init);
static void __exit max7301_exit(void)
{
spi_unregister_driver(&max7301_driver);
}
-
-module_init(max7301_init);
module_exit(max7301_exit);
MODULE_AUTHOR("Juergen Beisert");
diff --git a/drivers/gpio/max732x.c b/drivers/gpio/max732x.c
index b51c8135ca28..55ae9a41897a 100644
--- a/drivers/gpio/max732x.c
+++ b/drivers/gpio/max732x.c
@@ -372,7 +372,10 @@ static int __init max732x_init(void)
{
return i2c_add_driver(&max732x_driver);
}
-module_init(max732x_init);
+/* register after i2c postcore initcall and before
+ * subsys initcalls that may rely on these GPIOs
+ */
+subsys_initcall(max732x_init);
static void __exit max732x_exit(void)
{
diff --git a/drivers/gpio/mcp23s08.c b/drivers/gpio/mcp23s08.c
index 8a1b405fefda..89c1d222e9d1 100644
--- a/drivers/gpio/mcp23s08.c
+++ b/drivers/gpio/mcp23s08.c
@@ -419,7 +419,10 @@ static int __init mcp23s08_init(void)
{
return spi_register_driver(&mcp23s08_driver);
}
-module_init(mcp23s08_init);
+/* register after spi postcore initcall and before
+ * subsys initcalls that may rely on these GPIOs
+ */
+subsys_initcall(mcp23s08_init);
static void __exit mcp23s08_exit(void)
{
diff --git a/drivers/gpio/pca953x.c b/drivers/gpio/pca953x.c
index cc8468692ae0..9ceeb89f1325 100644
--- a/drivers/gpio/pca953x.c
+++ b/drivers/gpio/pca953x.c
@@ -289,7 +289,10 @@ static int __init pca953x_init(void)
{
return i2c_add_driver(&pca953x_driver);
}
-module_init(pca953x_init);
+/* register after i2c postcore initcall and before
+ * subsys initcalls that may rely on these GPIOs
+ */
+subsys_initcall(pca953x_init);
static void __exit pca953x_exit(void)
{
diff --git a/drivers/gpio/pcf857x.c b/drivers/gpio/pcf857x.c
index fc9c6ae739ee..4bc2070dd4a1 100644
--- a/drivers/gpio/pcf857x.c
+++ b/drivers/gpio/pcf857x.c
@@ -351,7 +351,10 @@ static int __init pcf857x_init(void)
{
return i2c_add_driver(&pcf857x_driver);
}
-module_init(pcf857x_init);
+/* register after i2c postcore initcall and before
+ * subsys initcalls that may rely on these GPIOs
+ */
+subsys_initcall(pcf857x_init);
static void __exit pcf857x_exit(void)
{
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-12-18 08:44:19 +0000