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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: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Mika Westerberg 2014-03-10 14:54:51 +02:00 committed by Linus Walleij
parent 77c2d7929d
commit aa92b6f689
1 changed files with 64 additions and 42 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

106
drivers/gpio/gpiolib-acpi.c
View File

@ -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);
}