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gpio: Break out code to get a descriptor from a DT node
Sometimes a GPIO needs to be taken from a node without a device associated with it. The fwnode accessor does this, let's however break out the DT code for now. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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6a537d4846
commit
6392cca42d
1 changed files with 88 additions and 39 deletions
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@ -3668,65 +3668,48 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
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EXPORT_SYMBOL_GPL(gpiod_get_index);
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/**
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* fwnode_get_named_gpiod - obtain a GPIO from firmware node
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* @fwnode: handle of the firmware node
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* @propname: name of the firmware property representing the GPIO
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* @index: index of the GPIO to obtain in the consumer
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* gpiod_get_from_of_node() - obtain a GPIO from an OF node
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* @node: handle of the OF node
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* @propname: name of the DT property representing the GPIO
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* @index: index of the GPIO to obtain for the consumer
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* @dflags: GPIO initialization flags
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* @label: label to attach to the requested GPIO
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*
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* This function can be used for drivers that get their configuration
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* from firmware.
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*
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* Function properly finds the corresponding GPIO using whatever is the
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* underlying firmware interface and then makes sure that the GPIO
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* descriptor is requested before it is returned to the caller.
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*
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* Returns:
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* On successful request the GPIO pin is configured in accordance with
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* provided @dflags.
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* provided @dflags. If the node does not have the requested GPIO
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* property, NULL is returned.
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*
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* In case of error an ERR_PTR() is returned.
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*/
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struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
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const char *propname, int index,
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enum gpiod_flags dflags,
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const char *label)
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static struct gpio_desc *gpiod_get_from_of_node(struct device_node *node,
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const char *propname, int index,
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enum gpiod_flags dflags,
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const char *label)
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{
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struct gpio_desc *desc = ERR_PTR(-ENODEV);
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unsigned long lflags = 0;
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enum of_gpio_flags flags;
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bool active_low = false;
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bool single_ended = false;
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bool open_drain = false;
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bool transitory = false;
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int ret;
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if (!fwnode)
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return ERR_PTR(-EINVAL);
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desc = of_get_named_gpiod_flags(node, propname,
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index, &flags);
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if (is_of_node(fwnode)) {
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enum of_gpio_flags flags;
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desc = of_get_named_gpiod_flags(to_of_node(fwnode), propname,
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index, &flags);
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if (!IS_ERR(desc)) {
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active_low = flags & OF_GPIO_ACTIVE_LOW;
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single_ended = flags & OF_GPIO_SINGLE_ENDED;
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open_drain = flags & OF_GPIO_OPEN_DRAIN;
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transitory = flags & OF_GPIO_TRANSITORY;
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}
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} else if (is_acpi_node(fwnode)) {
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struct acpi_gpio_info info;
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desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
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if (!IS_ERR(desc)) {
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active_low = info.polarity == GPIO_ACTIVE_LOW;
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acpi_gpio_update_gpiod_flags(&dflags, &info);
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}
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if (!desc || IS_ERR(desc)) {
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/* If it is not there, just return NULL */
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if (PTR_ERR(desc) == -ENOENT)
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return NULL;
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return desc;
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}
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if (IS_ERR(desc))
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return desc;
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active_low = flags & OF_GPIO_ACTIVE_LOW;
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single_ended = flags & OF_GPIO_SINGLE_ENDED;
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open_drain = flags & OF_GPIO_OPEN_DRAIN;
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transitory = flags & OF_GPIO_TRANSITORY;
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ret = gpiod_request(desc, label);
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if (ret)
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@ -3753,6 +3736,72 @@ struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
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return desc;
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}
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/**
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* fwnode_get_named_gpiod - obtain a GPIO from firmware node
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* @fwnode: handle of the firmware node
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* @propname: name of the firmware property representing the GPIO
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* @index: index of the GPIO to obtain for the consumer
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* @dflags: GPIO initialization flags
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* @label: label to attach to the requested GPIO
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*
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* This function can be used for drivers that get their configuration
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* from opaque firmware.
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*
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* The function properly finds the corresponding GPIO using whatever is the
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* underlying firmware interface and then makes sure that the GPIO
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* descriptor is requested before it is returned to the caller.
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*
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* Returns:
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* On successful request the GPIO pin is configured in accordance with
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* provided @dflags.
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*
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* In case of error an ERR_PTR() is returned.
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*/
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struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
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const char *propname, int index,
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enum gpiod_flags dflags,
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const char *label)
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{
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struct gpio_desc *desc = ERR_PTR(-ENODEV);
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unsigned long lflags = 0;
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int ret;
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if (!fwnode)
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return ERR_PTR(-EINVAL);
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if (is_of_node(fwnode)) {
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desc = gpiod_get_from_of_node(to_of_node(fwnode),
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propname, index,
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dflags,
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label);
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return desc;
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} else if (is_acpi_node(fwnode)) {
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struct acpi_gpio_info info;
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desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
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if (IS_ERR(desc))
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return desc;
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acpi_gpio_update_gpiod_flags(&dflags, &info);
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if (info.polarity == GPIO_ACTIVE_LOW)
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lflags |= GPIO_ACTIVE_LOW;
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}
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/* Currently only ACPI takes this path */
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ret = gpiod_request(desc, label);
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if (ret)
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return ERR_PTR(ret);
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ret = gpiod_configure_flags(desc, propname, lflags, dflags);
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if (ret < 0) {
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gpiod_put(desc);
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return ERR_PTR(ret);
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}
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return desc;
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}
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EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
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/**
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