Commit aa92b6f6 authored by Mika Westerberg's avatar Mika Westerberg Committed by Linus Walleij
Browse files

gpio / ACPI: Allocate ACPI specific data directly in acpi_gpiochip_add() 



We are going to add more ACPI specific data to accompany GPIO chip so
instead of allocating it per each use-case we allocate it once when
acpi_gpiochip_add() is called and release it when acpi_gpiochip_remove() is
called.

Doing this allows us to add more ACPI specific data by merely adding new
fields to struct acpi_gpio_chip.

In addition we embed evt_pins member directly to the structure instead of
having it as a pointer. This simplifies the code a bit since we don't need
to check against NULL.

Signed-off-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent 77c2d792

drivers/gpio/gpiolib-acpi.c

+64 −42
Original line number Diff line number Diff line
@@ -26,6 +26,11 @@ struct acpi_gpio_evt_pin { 
	unsigned int irq;

};



struct acpi_gpio_chip {

	struct gpio_chip *chip;

	struct list_head evt_pins;

};



static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)

{

	if (!gc->dev)
@@ -81,14 +86,14 @@ static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data) 
	return IRQ_HANDLED;

}



static void acpi_gpio_evt_dh(acpi_handle handle, void *data)

static void acpi_gpio_chip_dh(acpi_handle handle, void *data)

{

	/* The address of this function is used as a key. */

}



/**

 * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events

 * @chip:      gpio chip

 * @acpi_gpio:      ACPI GPIO chip

 *

 * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are

 * handled by ACPI event methods which need to be called from the GPIO
@@ -96,12 +101,12 @@ static void acpi_gpio_evt_dh(acpi_handle handle, void *data) 
 * gpio pins have acpi event methods and assigns interrupt handlers that calls

 * the acpi event methods for those pins.

 */

static void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)

static void acpi_gpiochip_request_interrupts(struct acpi_gpio_chip *acpi_gpio)

{

	struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};

	struct gpio_chip *chip = acpi_gpio->chip;

	struct acpi_resource *res;

	acpi_handle handle, evt_handle;

	struct list_head *evt_pins = NULL;

	acpi_status status;

	unsigned int pin;

	int irq, ret;
@@ -114,23 +119,7 @@ static void acpi_gpiochip_request_interrupts(struct gpio_chip *chip) 
	if (!handle)

		return;



	status = acpi_get_event_resources(handle, &buf);

	if (ACPI_FAILURE(status))

		return;



	status = acpi_get_handle(handle, "_EVT", &evt_handle);

	if (ACPI_SUCCESS(status)) {

		evt_pins = kzalloc(sizeof(*evt_pins), GFP_KERNEL);

		if (evt_pins) {

			INIT_LIST_HEAD(evt_pins);

			status = acpi_attach_data(handle, acpi_gpio_evt_dh,

						  evt_pins);

			if (ACPI_FAILURE(status)) {

				kfree(evt_pins);

				evt_pins = NULL;

			}

		}

	}

	INIT_LIST_HEAD(&acpi_gpio->evt_pins);



	/*

	 * If a GPIO interrupt has an ACPI event handler method, or _EVT is
@@ -167,14 +156,18 @@ static void acpi_gpiochip_request_interrupts(struct gpio_chip *chip) 
				data = ev_handle;

			}

		}

		if (!handler && evt_pins) {

		if (!handler) {

			struct acpi_gpio_evt_pin *evt_pin;



			status = acpi_get_handle(handle, "_EVT", &evt_handle);

			if (ACPI_FAILURE(status))

				continue



			evt_pin = kzalloc(sizeof(*evt_pin), GFP_KERNEL);

			if (!evt_pin)

				continue;



			list_add_tail(&evt_pin->node, evt_pins);

			list_add_tail(&evt_pin->node, &acpi_gpio->evt_pins);

			evt_pin->evt_handle = evt_handle;

			evt_pin->pin = pin;

			evt_pin->irq = irq;
@@ -197,39 +190,27 @@ static void acpi_gpiochip_request_interrupts(struct gpio_chip *chip) 


/**

 * acpi_gpiochip_free_interrupts() - Free GPIO _EVT ACPI event interrupts.

 * @chip:      gpio chip

 * @acpi_gpio:      ACPI GPIO chip

 *

 * Free interrupts associated with the _EVT method for the given GPIO chip.

 *

 * The remaining ACPI event interrupts associated with the chip are freed

 * automatically.

 */

static void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)

static void acpi_gpiochip_free_interrupts(struct acpi_gpio_chip *acpi_gpio)

{

	acpi_handle handle;

	acpi_status status;

	struct list_head *evt_pins;

	struct acpi_gpio_evt_pin *evt_pin, *ep;

	struct gpio_chip *chip = acpi_gpio->chip;



	if (!chip->dev || !chip->to_irq)

		return;



	handle = ACPI_HANDLE(chip->dev);

	if (!handle)

		return;



	status = acpi_get_data(handle, acpi_gpio_evt_dh, (void **)&evt_pins);

	if (ACPI_FAILURE(status))

		return;



	list_for_each_entry_safe_reverse(evt_pin, ep, evt_pins, node) {

	list_for_each_entry_safe_reverse(evt_pin, ep, &acpi_gpio->evt_pins,

					 node) {

		devm_free_irq(chip->dev, evt_pin->irq, evt_pin);

		list_del(&evt_pin->node);

		kfree(evt_pin);

	}



	acpi_detach_data(handle, acpi_gpio_evt_dh);

	kfree(evt_pins);

}



struct acpi_gpio_lookup {
@@ -312,10 +293,51 @@ struct gpio_desc *acpi_get_gpiod_by_index(struct device *dev, int index, 


void acpi_gpiochip_add(struct gpio_chip *chip)

{

	acpi_gpiochip_request_interrupts(chip);

	struct acpi_gpio_chip *acpi_gpio;

	acpi_handle handle;

	acpi_status status;



	handle = ACPI_HANDLE(chip->dev);

	if (!handle)

		return;



	acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);

	if (!acpi_gpio) {

		dev_err(chip->dev,

			"Failed to allocate memory for ACPI GPIO chip\n");

		return;

	}



	acpi_gpio->chip = chip;



	status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);

	if (ACPI_FAILURE(status)) {

		dev_err(chip->dev, "Failed to attach ACPI GPIO chip\n");

		kfree(acpi_gpio);

		return;

	}



	acpi_gpiochip_request_interrupts(acpi_gpio);

}



void acpi_gpiochip_remove(struct gpio_chip *chip)

{

	acpi_gpiochip_free_interrupts(chip);

	struct acpi_gpio_chip *acpi_gpio;

	acpi_handle handle;

	acpi_status status;



	handle = ACPI_HANDLE(chip->dev);

	if (!handle)

		return;



	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);

	if (ACPI_FAILURE(status)) {

		dev_warn(chip->dev, "Failed to retrieve ACPI GPIO chip\n");

		return;

	}



	acpi_gpiochip_free_interrupts(acpi_gpio);



	acpi_detach_data(handle, acpi_gpio_chip_dh);

	kfree(acpi_gpio);

}

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