On Tue, Feb 10, 2015 at 02:40:52PM +0100, Rojhalat Ibrahim wrote:
> +#ifdef CONFIG_ACPI
> +
> +static unsigned int acpi_gpio_package_count(const union acpi_object *obj)
> +{
> + const union acpi_object *element = obj->package.elements;
> + const union acpi_object *end = element + obj->package.count;
> + unsigned int count = 0;
> +
> + while (element < end) {
> + if (element->type == ACPI_TYPE_LOCAL_REFERENCE)
> + count++;
> +
> + element++;
> + }
> + return count;
> +}
> +
> +static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
> +{
> + unsigned int *count = data;
> +
> + if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
> + *count += ares->data.gpio.pin_table_length;
> +
> + return 1;
> +}
> +
> +static int acpi_gpio_count(struct device *dev, const char *con_id)
> +{
> + struct acpi_device *adev = ACPI_COMPANION(dev);
> + const union acpi_object *obj;
> + const struct acpi_gpio_mapping *gm;
> + int count = -ENOENT;
> + int ret;
> + char propname[32];
> + unsigned int i;
> +
> + /* Try first from _DSD */
> + for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
> + if (con_id && strcmp(con_id, "gpios"))
> + snprintf(propname, sizeof(propname), "%s-%s",
> + con_id, gpio_suffixes[i]);
> + else
> + snprintf(propname, sizeof(propname), "%s",
> + gpio_suffixes[i]);
> +
> + ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
> + &obj);
> + if (ret == 0) {
> + if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
> + count = 1;
> + else if (obj->type == ACPI_TYPE_PACKAGE)
> + count = acpi_gpio_package_count(obj);
> + } else if (adev->driver_gpios) {
> + for (gm = adev->driver_gpios; gm->name; gm++)
> + if (strcmp(propname, gm->name) == 0) {
> + count = gm->size;
> + break;
> + }
> + }
> + if (count >= 0)
> + break;
> + }
> +
> + /* Then from plain _CRS GPIOs */
> + if (count < 0) {
> + struct list_head resource_list;
> + unsigned int crs_count = 0;
> +
> + INIT_LIST_HEAD(&resource_list);
> + acpi_dev_get_resources(adev, &resource_list,
> + acpi_find_gpio_count, &crs_count);
> + acpi_dev_free_resource_list(&resource_list);
> + if (crs_count > 0)
> + count = crs_count;
> + }
> + return count;
> +}
> +
> +#else
> +
> +static int acpi_gpio_count(struct device *dev, const char *con_id)
> +{
> + return -ENODEV;
> +}
> +
> +#endif
It just occured to me that it would be better to put this code to
gpiolib-acpi.c and declare acpi_gpio_count() in drivers/gpio/gpiolib.h.
That said, I tested this code on Lenovo Thinkpad10 by converting
drivers/input/misc/soc_button_array.c to fetch its GPIOs using this new
API -- it works just fine (and looks better).
Once you have done the above change you can add for the ACPI parts,
Reviewed-by: Mika Westerberg <[email protected]>
Tested-by: Mika Westerberg <[email protected]>
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