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gpio: pca953x: Override IRQ for one of the expanders on Galileo Gen 2

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ACPI table on Intel Galileo Gen 2 has wrong pin number for IRQ resource
of one of the I²C GPIO expanders. Since we know what that number is and
luckily have GPIO bases fixed for SoC's controllers, we may use a simple
DMI quirk to match the platform and retrieve GpioInt() pin on it for
the expander in question.

Mika suggested the way to avoid a quirk in the GPIO ACPI library and
here is the second, almost rewritten version of it.

Fixes: f32517bf1a ("gpio: pca953x: support ACPI devices found on Galileo Gen2")
Depends-on: 25e3ef894e ("gpio: acpi: Split out acpi_gpio_get_irq_resource() helper")
Suggested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
This commit is contained in:
Andy Shevchenko 2020-06-05 16:40:34 +03:00 committed by Bartosz Golaszewski
parent 064c73afe7
commit ba8c90c618
1 changed files with 79 additions and 0 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

79
drivers/gpio/gpio-pca953x.c
View file

@ -107,6 +107,79 @@ static const struct i2c_device_id pca953x_id[] = {
};
MODULE_DEVICE_TABLE(i2c, pca953x_id);
#ifdef CONFIG_GPIO_PCA953X_IRQ
#include <linux/dmi.h>
#include <linux/gpio.h>
#include <linux/list.h>
static const struct dmi_system_id pca953x_dmi_acpi_irq_info[] = {
{
/*
* On Intel Galileo Gen 2 board the IRQ pin of one of
* the I²C GPIO expanders, which has GpioInt() resource,
* is provided as an absolute number instead of being
* relative. Since first controller (gpio-sch.c) and
* second (gpio-dwapb.c) are at the fixed bases, we may
* safely refer to the number in the global space to get
* an IRQ out of it.
*/
.matches = {
DMI_EXACT_MATCH(DMI_BOARD_NAME, "GalileoGen2"),
},
},
{}
};
#ifdef CONFIG_ACPI
static int pca953x_acpi_get_pin(struct acpi_resource *ares, void *data)
{
struct acpi_resource_gpio *agpio;
int *pin = data;
if (acpi_gpio_get_irq_resource(ares, &agpio))
*pin = agpio->pin_table[0];
return 1;
}
static int pca953x_acpi_find_pin(struct device *dev)
{
struct acpi_device *adev = ACPI_COMPANION(dev);
int pin = -ENOENT, ret;
LIST_HEAD(r);
ret = acpi_dev_get_resources(adev, &r, pca953x_acpi_get_pin, &pin);
acpi_dev_free_resource_list(&r);
if (ret < 0)
return ret;
return pin;
}
#else
static inline int pca953x_acpi_find_pin(struct device *dev) { return -ENXIO; }
#endif
static int pca953x_acpi_get_irq(struct device *dev)
{
int pin, ret;
pin = pca953x_acpi_find_pin(dev);
if (pin < 0)
return pin;
dev_info(dev, "Applying ACPI interrupt quirk (GPIO %d)\n", pin);
if (!gpio_is_valid(pin))
return -EINVAL;
ret = gpio_request(pin, "pca953x interrupt");
if (ret)
return ret;
return gpio_to_irq(pin);
}
#endif
static const struct acpi_device_id pca953x_acpi_ids[] = {
{ "INT3491", 16 | PCA953X_TYPE | PCA_LATCH_INT, },
{ }
@ -754,6 +827,12 @@ static int pca953x_irq_setup(struct pca953x_chip *chip, int irq_base)
DECLARE_BITMAP(irq_stat, MAX_LINE);
int ret;
if (dmi_first_match(pca953x_dmi_acpi_irq_info)) {
ret = pca953x_acpi_get_irq(&client->dev);
if (ret > 0)
client->irq = ret;
}
if (!client->irq)
return 0;