From: Andy Shevchenko andriy.shevchenko@linux.intel.com
[ Upstream commit ba8c90c6184784b397807b72403656085ac2f8c1 ]
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: f32517bf1ae0 ("gpio: pca953x: support ACPI devices found on Galileo Gen2") Depends-on: 25e3ef894eef ("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 Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpio/gpio-pca953x.c | 79 +++++++++++++++++++++++++++++++++++++ 1 file changed, 79 insertions(+)
diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c index d8ba6c5195be7..8571e54512476 100644 --- a/drivers/gpio/gpio-pca953x.c +++ b/drivers/gpio/gpio-pca953x.c @@ -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, }, { } @@ -744,6 +817,12 @@ 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;