diff options
Diffstat (limited to 'drivers/gpio/gpiolib.c')
| -rw-r--r-- | drivers/gpio/gpiolib.c | 61 |
1 files changed, 57 insertions, 4 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index ec0fd95bbf35..56eec094184c 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -514,6 +514,10 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip) if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE) set_bit(FLAG_OPEN_SOURCE, &desc->flags); + ret = gpiod_set_transitory(desc, false); + if (ret < 0) + goto out_free_descs; + /* * Lines have to be requested explicitly for input * or output, else the line will be treated "as is". @@ -2530,6 +2534,49 @@ int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) EXPORT_SYMBOL_GPL(gpiod_set_debounce); /** + * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset + * @desc: descriptor of the GPIO for which to configure persistence + * @transitory: True to lose state on suspend or reset, false for persistence + * + * Returns: + * 0 on success, otherwise a negative error code. + */ +int gpiod_set_transitory(struct gpio_desc *desc, bool transitory) +{ + struct gpio_chip *chip; + unsigned long packed; + int gpio; + int rc; + + /* + * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for + * persistence state. + */ + if (transitory) + set_bit(FLAG_TRANSITORY, &desc->flags); + else + clear_bit(FLAG_TRANSITORY, &desc->flags); + + /* If the driver supports it, set the persistence state now */ + chip = desc->gdev->chip; + if (!chip->set_config) + return 0; + + packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE, + !transitory); + gpio = gpio_chip_hwgpio(desc); + rc = chip->set_config(chip, gpio, packed); + if (rc == -ENOTSUPP) { + dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n", + gpio); + return 0; + } + + return rc; +} +EXPORT_SYMBOL_GPL(gpiod_set_transitory); + +/** * gpiod_is_active_low - test whether a GPIO is active-low or not * @desc: the gpio descriptor to test * @@ -3116,8 +3163,7 @@ bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset) if (offset >= chip->ngpio) return false; - return !test_bit(FLAG_SLEEP_MAY_LOSE_VALUE, - &chip->gpiodev->descs[offset].flags); + return !test_bit(FLAG_TRANSITORY, &chip->gpiodev->descs[offset].flags); } EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent); @@ -3554,8 +3600,10 @@ int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, if (lflags & GPIO_OPEN_SOURCE) set_bit(FLAG_OPEN_SOURCE, &desc->flags); - if (lflags & GPIO_SLEEP_MAY_LOSE_VALUE) - set_bit(FLAG_SLEEP_MAY_LOSE_VALUE, &desc->flags); + + status = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY)); + if (status < 0) + return status; /* No particular flag request, return here... */ if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) { @@ -3669,6 +3717,7 @@ struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, bool active_low = false; bool single_ended = false; bool open_drain = false; + bool transitory = false; int ret; if (!fwnode) @@ -3683,6 +3732,7 @@ struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, active_low = flags & OF_GPIO_ACTIVE_LOW; single_ended = flags & OF_GPIO_SINGLE_ENDED; open_drain = flags & OF_GPIO_OPEN_DRAIN; + transitory = flags & OF_GPIO_TRANSITORY; } } else if (is_acpi_node(fwnode)) { struct acpi_gpio_info info; @@ -3711,6 +3761,9 @@ struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, lflags |= GPIO_OPEN_SOURCE; } + if (transitory) + lflags |= GPIO_TRANSITORY; + ret = gpiod_configure_flags(desc, propname, lflags, dflags); if (ret < 0) { gpiod_put(desc); |