[PATCH 3/6] gpiolib: acpi: teach acpi_find_gpio() to handle data-only nodes

Dmitry Torokhov
2022-11-04T06:11:02Z

In preparation of switching all ACPI-based GPIO lookups to go through
acpi_find_gpio() we need to make sure it can handle data-only ACPI
nodes, same as existing acpi_node_get_gpiod().

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
drivers/gpio/gpiolib-acpi.c | 76 +++++++++++++++++++++++++++++----------------
1 file changed, 50 insertions(+), 26 deletions(-)

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index ccb74e208989..d51bf2a3203d 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -864,8 +864,9 @@ static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
* function only returns the first.
*/
static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
- const char *propname, int index,
- struct acpi_gpio_info *info)
+ const char *propname,
+ int index,
+ struct acpi_gpio_info *info)
{
struct acpi_gpio_lookup lookup;
int ret;
@@ -896,6 +897,44 @@ static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
return ret ? ERR_PTR(ret) : lookup.desc;
}

+/**
+ * acpi_get_gpiod_from_data() - get a GPIO descriptor from ACPI data node
+ * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
+ * @propname: Property name of the GPIO
+ * @index: index of GpioIo/GpioInt resource (starting from %0)
+ * @info: info pointer to fill in (optional)
+ *
+ * This function uses the property-based GPIO lookup to get to the GPIO
+ * resource with the relevant information from a data-only ACPI firmware node
+ * and uses that to obtain the GPIO descriptor to return.
+ *
+ * If the GPIO cannot be translated or there is an error an ERR_PTR is
+ * returned.
+ */
+static struct gpio_desc *acpi_get_gpiod_from_data(struct fwnode_handle *fwnode,
+ const char *propname,
+ int index,
+ struct acpi_gpio_info *info)
+{
+ struct acpi_gpio_lookup lookup;
+ int ret;
+
+ if (!is_acpi_data_node(fwnode))
+ return ERR_PTR(-ENODEV);
+
+ if (!propname)
+ return ERR_PTR(-EINVAL);
+
+ lookup.index = index;
+
+ ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
+ if (ret)
+ return ERR_PTR(ret);
+
+ ret = acpi_gpio_resource_lookup(&lookup, info);
+ return ret ? ERR_PTR(ret) : lookup.desc;
+}
+
static bool acpi_can_fallback_to_crs(struct acpi_device *adev,
const char *con_id)
{
@@ -912,16 +951,12 @@ struct gpio_desc *acpi_find_gpio(struct fwnode_handle *fwnode,
enum gpiod_flags *dflags,
unsigned long *lookupflags)
{
- struct acpi_device *adev;
+ struct acpi_device *adev = to_acpi_device_node(fwnode);
struct acpi_gpio_info info;
struct gpio_desc *desc;
char propname[32];
int i;

- adev = to_acpi_device_node(fwnode);
- if (!adev)
- return ERR_PTR(-ENODEV);
-
/* Try first from _DSD */
for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
if (con_id) {
@@ -932,7 +967,12 @@ struct gpio_desc *acpi_find_gpio(struct fwnode_handle *fwnode,
gpio_suffixes[i]);
}

- desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
+ if (adev)
+ desc = acpi_get_gpiod_by_index(adev,
+ propname, idx, &info);
+ else
+ desc = acpi_get_gpiod_from_data(fwnode,
+ propname, idx, &info);
if (!IS_ERR(desc))
break;
if (PTR_ERR(desc) == -EPROBE_DEFER)
@@ -941,7 +981,7 @@ struct gpio_desc *acpi_find_gpio(struct fwnode_handle *fwnode,

/* Then from plain _CRS GPIOs */
if (IS_ERR(desc)) {
- if (!acpi_can_fallback_to_crs(adev, con_id))
+ if (!adev || !acpi_can_fallback_to_crs(adev, con_id))
return ERR_PTR(-ENOENT);

desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
@@ -979,29 +1019,13 @@ struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
const char *propname, int index,
struct acpi_gpio_info *info)
{
- struct acpi_gpio_lookup lookup;
struct acpi_device *adev;
- int ret;

adev = to_acpi_device_node(fwnode);
if (adev)
return acpi_get_gpiod_by_index(adev, propname, index, info);

- if (!is_acpi_data_node(fwnode))
- return ERR_PTR(-ENODEV);
-
- if (!propname)
- return ERR_PTR(-EINVAL);
-
- memset(&lookup, 0, sizeof(lookup));
- lookup.index = index;
-
- ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
- if (ret)
- return ERR_PTR(ret);
-
- ret = acpi_gpio_resource_lookup(&lookup, info);
- return ret ? ERR_PTR(ret) : lookup.desc;
+ return acpi_get_gpiod_from_data(fwnode, propname, index, info);
}

/**

--
b4 0.11.0-dev-28747