diff options
Diffstat (limited to 'drivers/gpio/gpiolib.c')
-rw-r--r-- | drivers/gpio/gpiolib.c | 255 |
1 files changed, 139 insertions, 116 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 85f772c0b26..50c4922fe53 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; @@ -393,7 +413,7 @@ static const DEVICE_ATTR(value, 0644, static irqreturn_t gpio_sysfs_irq(int irq, void *priv) { - struct sysfs_dirent *value_sd = priv; + struct kernfs_node *value_sd = priv; sysfs_notify_dirent(value_sd); return IRQ_HANDLED; @@ -402,7 +422,7 @@ static irqreturn_t gpio_sysfs_irq(int irq, void *priv) static int gpio_setup_irq(struct gpio_desc *desc, struct device *dev, unsigned long gpio_flags) { - struct sysfs_dirent *value_sd; + struct kernfs_node *value_sd; unsigned long irq_flags; int ret, irq, id; @@ -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)) { |