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path: root/drivers/gpio/gpiolib.c
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Diffstat (limited to 'drivers/gpio/gpiolib.c')
-rw-r--r--drivers/gpio/gpiolib.c251
1 files changed, 137 insertions, 114 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index c8a7c810bade..50c4922fe53a 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -10,12 +10,13 @@
#include <linux/seq_file.h>
#include <linux/gpio.h>
#include <linux/of_gpio.h>
-#include <linux/acpi_gpio.h>
#include <linux/idr.h>
#include <linux/slab.h>
#include <linux/acpi.h>
#include <linux/gpio/driver.h>
+#include "gpiolib.h"
+
#define CREATE_TRACE_POINTS
#include <trace/events/gpio.h>
@@ -84,40 +85,57 @@ static DEFINE_IDR(dirent_idr);
static int gpiod_request(struct gpio_desc *desc, const char *label);
static void gpiod_free(struct gpio_desc *desc);
+/* With descriptor prefix */
+
#ifdef CONFIG_DEBUG_FS
-#define gpiod_emerg(desc, fmt, ...) \
- pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label, \
+#define gpiod_emerg(desc, fmt, ...) \
+ pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
##__VA_ARGS__)
-#define gpiod_crit(desc, fmt, ...) \
- pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label, \
+#define gpiod_crit(desc, fmt, ...) \
+ pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
##__VA_ARGS__)
-#define gpiod_err(desc, fmt, ...) \
- pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label, \
+#define gpiod_err(desc, fmt, ...) \
+ pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
##__VA_ARGS__)
-#define gpiod_warn(desc, fmt, ...) \
- pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label, \
+#define gpiod_warn(desc, fmt, ...) \
+ pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
##__VA_ARGS__)
-#define gpiod_info(desc, fmt, ...) \
- pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label, \
+#define gpiod_info(desc, fmt, ...) \
+ pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
##__VA_ARGS__)
-#define gpiod_dbg(desc, fmt, ...) \
- pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label, \
+#define gpiod_dbg(desc, fmt, ...) \
+ pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
##__VA_ARGS__)
#else
-#define gpiod_emerg(desc, fmt, ...) \
+#define gpiod_emerg(desc, fmt, ...) \
pr_emerg("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__)
-#define gpiod_crit(desc, fmt, ...) \
+#define gpiod_crit(desc, fmt, ...) \
pr_crit("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__)
-#define gpiod_err(desc, fmt, ...) \
+#define gpiod_err(desc, fmt, ...) \
pr_err("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__)
-#define gpiod_warn(desc, fmt, ...) \
+#define gpiod_warn(desc, fmt, ...) \
pr_warn("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__)
-#define gpiod_info(desc, fmt, ...) \
+#define gpiod_info(desc, fmt, ...) \
pr_info("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__)
-#define gpiod_dbg(desc, fmt, ...) \
+#define gpiod_dbg(desc, fmt, ...) \
pr_debug("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__)
#endif
+/* With chip prefix */
+
+#define chip_emerg(chip, fmt, ...) \
+ pr_emerg("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
+#define chip_crit(chip, fmt, ...) \
+ pr_crit("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
+#define chip_err(chip, fmt, ...) \
+ pr_err("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
+#define chip_warn(chip, fmt, ...) \
+ pr_warn("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
+#define chip_info(chip, fmt, ...) \
+ pr_info("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
+#define chip_dbg(chip, fmt, ...) \
+ pr_debug("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
+
static inline void desc_set_label(struct gpio_desc *d, const char *label)
{
#ifdef CONFIG_DEBUG_FS
@@ -151,9 +169,10 @@ EXPORT_SYMBOL_GPL(gpio_to_desc);
static struct gpio_desc *gpiochip_offset_to_desc(struct gpio_chip *chip,
unsigned int offset)
{
- unsigned int gpio = chip->base + offset;
+ if (offset >= chip->ngpio)
+ return ERR_PTR(-EINVAL);
- return gpio_to_desc(gpio);
+ return &chip->desc[offset];
}
/**
@@ -187,7 +206,8 @@ static int gpio_ensure_requested(struct gpio_desc *desc)
if (WARN(test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0,
"autorequest GPIO-%d\n", gpio)) {
if (!try_module_get(chip->owner)) {
- pr_err("GPIO-%d: module can't be gotten \n", gpio);
+ gpiod_err(desc, "%s: module can't be gotten\n",
+ __func__);
clear_bit(FLAG_REQUESTED, &desc->flags);
/* lose */
return -EIO;
@@ -808,8 +828,8 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
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__, desc_to_gpio(desc),
+ gpiod_dbg(desc, "%s: unavailable (requested=%d, exported=%d)\n",
+ __func__,
test_bit(FLAG_REQUESTED, &desc->flags),
test_bit(FLAG_EXPORT, &desc->flags));
status = -EPERM;
@@ -857,8 +877,7 @@ fail_unregister_device:
device_unregister(dev);
fail_unlock:
mutex_unlock(&sysfs_lock);
- pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc),
- status);
+ gpiod_dbg(desc, "%s: status %d\n", __func__, status);
return status;
}
EXPORT_SYMBOL_GPL(gpiod_export);
@@ -906,8 +925,7 @@ int gpiod_export_link(struct device *dev, const char *name,
mutex_unlock(&sysfs_lock);
if (status)
- pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc),
- status);
+ gpiod_dbg(desc, "%s: status %d\n", __func__, status);
return status;
}
@@ -951,8 +969,7 @@ unlock:
mutex_unlock(&sysfs_lock);
if (status)
- pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc),
- status);
+ gpiod_dbg(desc, "%s: status %d\n", __func__, status);
return status;
}
@@ -994,8 +1011,7 @@ void gpiod_unexport(struct gpio_desc *desc)
}
if (status)
- pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc),
- status);
+ gpiod_dbg(desc, "%s: status %d\n", __func__, status);
}
EXPORT_SYMBOL_GPL(gpiod_unexport);
@@ -1034,8 +1050,7 @@ static int gpiochip_export(struct gpio_chip *chip)
chip->desc[gpio++].chip = NULL;
spin_unlock_irqrestore(&gpio_lock, flags);
- pr_debug("%s: chip %s status %d\n", __func__,
- chip->label, status);
+ chip_dbg(chip, "%s: status %d\n", __func__, status);
}
return status;
@@ -1051,15 +1066,14 @@ static void gpiochip_unexport(struct gpio_chip *chip)
if (dev) {
put_device(dev);
device_unregister(dev);
- chip->exported = 0;
+ chip->exported = false;
status = 0;
} else
status = -ENODEV;
mutex_unlock(&sysfs_lock);
if (status)
- pr_debug("%s: chip %s status %d\n", __func__,
- chip->label, status);
+ chip_dbg(chip, "%s: status %d\n", __func__, status);
}
static int __init gpiolib_sysfs_init(void)
@@ -1213,6 +1227,7 @@ int gpiochip_add(struct gpio_chip *chip)
#endif
of_gpiochip_add(chip);
+ acpi_gpiochip_add(chip);
if (status)
goto fail;
@@ -1221,7 +1236,7 @@ int gpiochip_add(struct gpio_chip *chip)
if (status)
goto fail;
- pr_debug("gpiochip_add: registered GPIOs %d to %d on device: %s\n",
+ pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__,
chip->base, chip->base + chip->ngpio - 1,
chip->label ? : "generic");
@@ -1231,7 +1246,7 @@ unlock:
spin_unlock_irqrestore(&gpio_lock, flags);
fail:
/* failures here can mean systems won't boot... */
- pr_err("gpiochip_add: gpios %d..%d (%s) failed to register\n",
+ pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__,
chip->base, chip->base + chip->ngpio - 1,
chip->label ? : "generic");
return status;
@@ -1254,6 +1269,7 @@ int gpiochip_remove(struct gpio_chip *chip)
gpiochip_remove_pin_ranges(chip);
of_gpiochip_remove(chip);
+ acpi_gpiochip_remove(chip);
for (id = 0; id < chip->ngpio; id++) {
if (test_bit(FLAG_REQUESTED, &chip->desc[id].flags)) {
@@ -1339,8 +1355,7 @@ int gpiochip_add_pingroup_range(struct gpio_chip *chip,
pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
if (!pin_range) {
- pr_err("%s: GPIO chip: failed to allocate pin ranges\n",
- chip->label);
+ chip_err(chip, "failed to allocate pin ranges\n");
return -ENOMEM;
}
@@ -1361,9 +1376,8 @@ int gpiochip_add_pingroup_range(struct gpio_chip *chip,
pinctrl_add_gpio_range(pctldev, &pin_range->range);
- pr_debug("GPIO chip %s: created GPIO range %d->%d ==> %s PINGRP %s\n",
- chip->label, gpio_offset,
- gpio_offset + pin_range->range.npins - 1,
+ chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n",
+ gpio_offset, gpio_offset + pin_range->range.npins - 1,
pinctrl_dev_get_devname(pctldev), pin_group);
list_add_tail(&pin_range->node, &chip->pin_ranges);
@@ -1390,8 +1404,7 @@ int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
if (!pin_range) {
- pr_err("%s: GPIO chip: failed to allocate pin ranges\n",
- chip->label);
+ chip_err(chip, "failed to allocate pin ranges\n");
return -ENOMEM;
}
@@ -1406,13 +1419,12 @@ int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
&pin_range->range);
if (IS_ERR(pin_range->pctldev)) {
ret = PTR_ERR(pin_range->pctldev);
- pr_err("%s: GPIO chip: could not create pin range\n",
- chip->label);
+ chip_err(chip, "could not create pin range\n");
kfree(pin_range);
return ret;
}
- pr_debug("GPIO chip %s: created GPIO range %d->%d ==> %s PIN %d->%d\n",
- chip->label, gpio_offset, gpio_offset + npins - 1,
+ chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
+ gpio_offset, gpio_offset + npins - 1,
pinctl_name,
pin_offset, pin_offset + npins - 1);
@@ -1499,8 +1511,7 @@ static int gpiod_request(struct gpio_desc *desc, const char *label)
}
done:
if (status)
- pr_debug("_gpio_request: gpio-%d (%s) status %d\n",
- desc_to_gpio(desc), label ? : "?", status);
+ gpiod_dbg(desc, "%s: status %d\n", __func__, status);
spin_unlock_irqrestore(&gpio_lock, flags);
return status;
}
@@ -1701,7 +1712,7 @@ int gpiod_direction_input(struct gpio_desc *desc)
if (!chip->get || !chip->direction_input) {
gpiod_warn(desc,
"%s: missing get() or direction_input() operations\n",
- __func__);
+ __func__);
return -EIO;
}
@@ -1721,7 +1732,8 @@ int gpiod_direction_input(struct gpio_desc *desc)
if (status) {
status = chip->request(chip, offset);
if (status < 0) {
- gpiod_dbg(desc, "chip request fail, %d\n", status);
+ gpiod_dbg(desc, "%s: chip request fail, %d\n",
+ __func__, status);
/* and it's not available to anyone else ...
* gpio_request() is the fully clean solution.
*/
@@ -1739,7 +1751,7 @@ lose:
fail:
spin_unlock_irqrestore(&gpio_lock, flags);
if (status)
- gpiod_dbg(desc, "%s status %d\n", __func__, status);
+ gpiod_dbg(desc, "%s: status %d\n", __func__, status);
return status;
}
EXPORT_SYMBOL_GPL(gpiod_direction_input);
@@ -1806,7 +1818,8 @@ int gpiod_direction_output(struct gpio_desc *desc, int value)
if (status) {
status = chip->request(chip, offset);
if (status < 0) {
- gpiod_dbg(desc, "chip request fail, %d\n", status);
+ gpiod_dbg(desc, "%s: chip request fail, %d\n",
+ __func__, status);
/* and it's not available to anyone else ...
* gpio_request() is the fully clean solution.
*/
@@ -2259,18 +2272,14 @@ void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
/**
- * gpiod_add_table() - register GPIO device consumers
- * @table: array of consumers to register
- * @num: number of consumers in table
+ * gpiod_add_lookup_table() - register GPIO device consumers
+ * @table: table of consumers to register
*/
-void gpiod_add_table(struct gpiod_lookup *table, size_t size)
+void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
{
mutex_lock(&gpio_lookup_lock);
- while (size--) {
- list_add_tail(&table->list, &gpio_lookup_list);
- table++;
- }
+ list_add_tail(&table->list, &gpio_lookup_list);
mutex_unlock(&gpio_lookup_lock);
}
@@ -2326,76 +2335,92 @@ static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id,
return desc;
}
-static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
- unsigned int idx,
- enum gpio_lookup_flags *flags)
+static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
{
const char *dev_id = dev ? dev_name(dev) : NULL;
- struct gpio_desc *desc = ERR_PTR(-ENODEV);
- unsigned int match, best = 0;
- struct gpiod_lookup *p;
+ struct gpiod_lookup_table *table;
mutex_lock(&gpio_lookup_lock);
- list_for_each_entry(p, &gpio_lookup_list, list) {
- match = 0;
+ list_for_each_entry(table, &gpio_lookup_list, list) {
+ if (table->dev_id && dev_id) {
+ /*
+ * Valid strings on both ends, must be identical to have
+ * a match
+ */
+ if (!strcmp(table->dev_id, dev_id))
+ goto found;
+ } else {
+ /*
+ * One of the pointers is NULL, so both must be to have
+ * a match
+ */
+ if (dev_id == table->dev_id)
+ goto found;
+ }
+ }
+ table = NULL;
- if (p->dev_id) {
- if (!dev_id || strcmp(p->dev_id, dev_id))
- continue;
+found:
+ mutex_unlock(&gpio_lookup_lock);
+ return table;
+}
- match += 2;
- }
+static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
+ unsigned int idx,
+ enum gpio_lookup_flags *flags)
+{
+ struct gpio_desc *desc = ERR_PTR(-ENOENT);
+ struct gpiod_lookup_table *table;
+ struct gpiod_lookup *p;
- if (p->con_id) {
- if (!con_id || strcmp(p->con_id, con_id))
- continue;
+ table = gpiod_find_lookup_table(dev);
+ if (!table)
+ return desc;
- match += 1;
- }
+ for (p = &table->table[0]; p->chip_label; p++) {
+ struct gpio_chip *chip;
+ /* idx must always match exactly */
if (p->idx != idx)
continue;
- if (match > best) {
- struct gpio_chip *chip;
+ /* If the lookup entry has a con_id, require exact match */
+ if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
+ continue;
- chip = find_chip_by_name(p->chip_label);
+ chip = find_chip_by_name(p->chip_label);
- if (!chip) {
- dev_warn(dev, "cannot find GPIO chip %s\n",
- p->chip_label);
- continue;
- }
+ if (!chip) {
+ dev_err(dev, "cannot find GPIO chip %s\n",
+ p->chip_label);
+ return ERR_PTR(-ENODEV);
+ }
- if (chip->ngpio <= p->chip_hwnum) {
- dev_warn(dev, "GPIO chip %s has %d GPIOs\n",
- chip->label, chip->ngpio);
- continue;
- }
+ if (chip->ngpio <= p->chip_hwnum) {
+ dev_err(dev,
+ "requested GPIO %d is out of range [0..%d] for chip %s\n",
+ idx, chip->ngpio, chip->label);
+ return ERR_PTR(-EINVAL);
+ }
- desc = gpio_to_desc(chip->base + p->chip_hwnum);
- *flags = p->flags;
+ desc = gpiochip_offset_to_desc(chip, p->chip_hwnum);
+ *flags = p->flags;
- if (match != 3)
- best = match;
- else
- break;
- }
+ return desc;
}
- mutex_unlock(&gpio_lookup_lock);
-
return desc;
}
/**
* gpio_get - obtain a GPIO for a given GPIO function
- * @dev: GPIO consumer
+ * @dev: GPIO consumer, can be NULL for system-global GPIOs
* @con_id: function within the GPIO consumer
*
* Return the GPIO descriptor corresponding to the function con_id of device
- * dev, or an IS_ERR() condition if an error occured.
+ * dev, -ENOENT if no GPIO has been assigned to the requested function, or
+ * another IS_ERR() code if an error occured while trying to acquire the GPIO.
*/
struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id)
{
@@ -2405,14 +2430,16 @@ EXPORT_SYMBOL_GPL(gpiod_get);
/**
* gpiod_get_index - obtain a GPIO from a multi-index GPIO function
- * @dev: GPIO consumer
+ * @dev: GPIO consumer, can be NULL for system-global GPIOs
* @con_id: function within the GPIO consumer
* @idx: index of the GPIO to obtain in the consumer
*
* This variant of gpiod_get() allows to access GPIOs other than the first
* defined one for functions that define several GPIOs.
*
- * Return a valid GPIO descriptor, or an IS_ERR() condition in case of error.
+ * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
+ * requested function and/or index, or another IS_ERR() code if an error
+ * occured while trying to acquire the GPIO.
*/
struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
const char *con_id,
@@ -2437,13 +2464,9 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
* Either we are not using DT or ACPI, or their lookup did not return
* a result. In that case, use platform lookup as a fallback.
*/
- if (!desc || IS_ERR(desc)) {
- struct gpio_desc *pdesc;
+ if (!desc || desc == ERR_PTR(-ENOENT)) {
dev_dbg(dev, "using lookup tables for GPIO lookup");
- pdesc = gpiod_find(dev, con_id, idx, &flags);
- /* If used as fallback, do not replace the previous error */
- if (!IS_ERR(pdesc) || !desc)
- desc = pdesc;
+ desc = gpiod_find(dev, con_id, idx, &flags);
}
if (IS_ERR(desc)) {
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-05 01:34:51 +0300