Now that static device properties understand notion of child nodes, let's
teach gpiolib to tie such children and machine GPIO descriptor tables.
We will continue using a single table for entire device, but instead of
using connection ID as a lookup key in the GPIO descriptor table directly,
we will perform additional translation: fwnode_get_named_gpiod() when
dealing with property_set-backed fwnodes will try parsing string property
with name matching connection ID and use result of the lookup as the key in
the table:
static const struct property_entry dev_child1_props[] __initconst = {
...
PROPERTY_ENTRY_STRING("gpios", "child-1-gpios"),
{ }
};
static struct gpiod_lookup_table dev_gpiod_table = {
.dev_id = "some-device",
.table = {
...
GPIO_LOOKUP_IDX("B", 1, "child-1-gpios", 1, GPIO_ACTIVE_LOW),
...
},
};
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
---
drivers/gpio/gpiolib.c | 108 ++++++++++++++++++++++++++++++-----------
1 file changed, 79 insertions(+), 29 deletions(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index e013d417a936..b6574febe2b8 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -4307,39 +4307,44 @@ struct gpio_desc *gpiod_get_from_of_node(struct device_node *node,
}
EXPORT_SYMBOL(gpiod_get_from_of_node);
-/**
- * fwnode_get_named_gpiod - obtain a GPIO from firmware node
- * @fwnode: handle of the firmware node
- * @propname: name of the firmware property representing the GPIO
- * @index: index of the GPIO to obtain for the consumer
- * @dflags: GPIO initialization flags
- * @label: label to attach to the requested GPIO
- *
- * This function can be used for drivers that get their configuration
- * from opaque firmware.
- *
- * The function properly finds the corresponding GPIO using whatever is the
- * underlying firmware interface and then makes sure that the GPIO
- * descriptor is requested before it is returned to the caller.
- *
- * Returns:
- * On successful request the GPIO pin is configured in accordance with
- * provided @dflags.
- *
- * In case of error an ERR_PTR() is returned.
- */
-struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
- const char *propname, int index,
- enum gpiod_flags dflags,
- const char *label)
+static struct gpio_desc *
+software_node_get_gpiod(struct fwnode_handle *fwnode,
+ const char *propname, int index, unsigned long *flags)
+{
+ struct device *dev;
+ const char *con_id;
+
+ dev = software_node_get_linked_device(fwnode);
+ if (IS_ERR_OR_NULL(dev))
+ return ERR_PTR(-EINVAL);
+
+ if (fwnode_property_read_string(fwnode, propname, &con_id)) {
+ /*
+ * We could not find string mapping property name to
+ * entry in gpio lookup table. Let's see if we are
+ * dealing with firmware node corresponding to the
+ * device (and not a child node): for such nodes we can
+ * try doing lookup directly with property name.
+ */
+ if (fwnode_get_parent(fwnode))
+ return ERR_PTR(-ENOENT);
+
+ con_id = propname;
+ }
+
+ return gpiod_find(dev, con_id, index, flags);
+}
+
+static struct gpio_desc *__fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
+ const char *propname,
+ int index,
+ enum gpiod_flags dflags,
+ const char *label)
{
unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
struct gpio_desc *desc = ERR_PTR(-ENODEV);
int ret;
- if (!fwnode)
- return ERR_PTR(-EINVAL);
-
if (is_of_node(fwnode)) {
desc = gpiod_get_from_of_node(to_of_node(fwnode),
propname, index,
@@ -4355,9 +4360,13 @@ struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
acpi_gpio_update_gpiod_flags(&dflags, &info);
acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
+ } else if (is_software_node(fwnode)) {
+ desc = software_node_get_gpiod(fwnode, propname, index,
+ &lflags);
+ if (IS_ERR(desc))
+ return desc;
}
- /* Currently only ACPI takes this path */
ret = gpiod_request(desc, label);
if (ret)
return ERR_PTR(ret);
@@ -4370,6 +4379,47 @@ struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
return desc;
}
+
+/**
+ * fwnode_get_named_gpiod - obtain a GPIO from firmware node
+ * @fwnode: handle of the firmware node
+ * @propname: name of the firmware property representing the GPIO
+ * @index: index of the GPIO to obtain for the consumer
+ * @dflags: GPIO initialization flags
+ * @label: label to attach to the requested GPIO
+ *
+ * This function can be used for drivers that get their configuration
+ * from opaque firmware.
+ *
+ * The function properly finds the corresponding GPIO using whatever is the
+ * underlying firmware interface and then makes sure that the GPIO
+ * descriptor is requested before it is returned to the caller.
+ *
+ * Returns:
+ * On successful request the GPIO pin is configured in accordance with
+ * provided @dflags.
+ *
+ * In case of error an ERR_PTR() is returned.
+ */
+struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
+ const char *propname, int index,
+ enum gpiod_flags dflags,
+ const char *label)
+{
+ struct gpio_desc *desc;
+
+ if (!fwnode)
+ return ERR_PTR(-EINVAL);
+
+ desc = __fwnode_get_named_gpiod(fwnode, propname, index, dflags, label);
+ if (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT &&
+ !IS_ERR_OR_NULL(fwnode->secondary)) {
+ desc = __fwnode_get_named_gpiod(fwnode->secondary,
+ propname, index, dflags, label);
+ }
+
+ return desc;
+}
EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
/**
--
2.22.0.510.g264f2c817a-goog
