gpio: acpi: Override GPIO initialization flags
This allows ACPI GPIO code to modify flags based on
ACPI GpioIo() / GpioInt() resources.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index cb61e11..e431222 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -448,6 +448,34 @@ acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio)
}
}
+int
+acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
+{
+ int ret = 0;
+
+ /*
+ * Check if the BIOS has IoRestriction with explicitly set direction
+ * and update @flags accordingly. Otherwise use whatever caller asked
+ * for.
+ */
+ if (update & GPIOD_FLAGS_BIT_DIR_SET) {
+ enum gpiod_flags diff = *flags ^ update;
+
+ /*
+ * Check if caller supplied incompatible GPIO initialization
+ * flags.
+ *
+ * Return %-EINVAL to notify that firmware has different
+ * settings and we are going to use them.
+ */
+ if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
+ ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
+ ret = -EINVAL;
+ *flags = update;
+ }
+ return ret;
+}
+
struct acpi_gpio_lookup {
struct acpi_gpio_info info;
int index;
@@ -485,8 +513,11 @@ static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
* - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
*/
if (lookup->info.gpioint) {
+ lookup->info.flags = GPIOD_IN;
lookup->info.polarity = agpio->polarity;
lookup->info.triggering = agpio->triggering;
+ } else {
+ lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio);
}
}
@@ -613,13 +644,14 @@ static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
struct gpio_desc *acpi_find_gpio(struct device *dev,
const char *con_id,
unsigned int idx,
- enum gpiod_flags flags,
+ enum gpiod_flags *dflags,
enum gpio_lookup_flags *lookupflags)
{
struct acpi_device *adev = ACPI_COMPANION(dev);
struct acpi_gpio_info info;
struct gpio_desc *desc;
char propname[32];
+ int err;
int i;
/* Try first from _DSD */
@@ -650,7 +682,7 @@ struct gpio_desc *acpi_find_gpio(struct device *dev,
}
if (info.gpioint &&
- (flags == GPIOD_OUT_LOW || flags == GPIOD_OUT_HIGH)) {
+ (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
return ERR_PTR(-ENOENT);
}
@@ -658,6 +690,10 @@ struct gpio_desc *acpi_find_gpio(struct device *dev,
if (info.polarity == GPIO_ACTIVE_LOW)
*lookupflags |= GPIO_ACTIVE_LOW;
+ err = acpi_gpio_update_gpiod_flags(dflags, info.flags);
+ if (err)
+ dev_dbg(dev, "Override GPIO initialization flags\n");
+
return desc;
}
@@ -711,12 +747,16 @@ struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
* used to translate from the GPIO offset in the resource to the Linux IRQ
* number.
*
+ * The function is idempotent, though each time it runs it will configure GPIO
+ * pin direction according to the flags in GpioInt resource.
+ *
* Return: Linux IRQ number (>%0) on success, negative errno on failure.
*/
int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
{
int idx, i;
unsigned int irq_flags;
+ int ret;
for (i = 0, idx = 0; idx <= index; i++) {
struct acpi_gpio_info info;
@@ -729,6 +769,7 @@ int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
return PTR_ERR(desc);
if (info.gpioint && idx++ == index) {
+ char label[32];
int irq;
if (IS_ERR(desc))
@@ -738,6 +779,11 @@ int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
if (irq < 0)
return irq;
+ snprintf(label, sizeof(label), "GpioInt() %d", index);
+ ret = gpiod_configure_flags(desc, label, 0, info.flags);
+ if (ret < 0)
+ return ret;
+
irq_flags = acpi_dev_get_irq_type(info.triggering,
info.polarity);