gpiolib: acpi: teach acpi_find_gpio() to handle data-only nodes

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().

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index 61b311e..bd36fac 100644 (file)
--- 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);
 }
 
 /**