Device trees allow mixing different kinds of GPIOs in one property. For
that it is usefull to only provide a pointer to an arbitrary location in
the property and initialize a GPIO from that.
---
bsps/arm/include/bsp/imx-gpio.h | 26 ++++++++++++++++
bsps/arm/shared/pins/imx-gpio.c | 55 ++++++++++++++++++++++++++-------
2 files changed, 69 insertions(+), 12 deletions(-)
diff --git a/bsps/arm/include/bsp/imx-gpio.h b/bsps/arm/include/bsp/imx-gpio.h
index 148f62a56e..5cda22972f 100644
--- a/bsps/arm/include/bsp/imx-gpio.h
+++ b/bsps/arm/include/bsp/imx-gpio.h
@@ -76,6 +76,32 @@ struct imx_gpio_pin {
*/
void imx_gpio_init (struct imx_gpio_pin *pin);
+/**
+ * Initialize a GPIO pin from the fields in an FDT property.
+ *
+ * If you have for example the following property in an FDT node:
+ *
+ * some-node {
+ * mixed-stuff = <0>, <&some_node 1>, <&gpio4 22 GPIO_ACTIVE_LOW>,
<17>;
+ * };
+ *
+ * You can get the property using fdt_getprop(...) in your code, somehow find
+ * the right start position (the phandle &gpio4) and then pass it to this
+ * function.
+ *
+ * If you pass something != NULL to @a next_prop_pointer, you will get a
pointer
+ * to the next part in the attribute. In the example above, that will be a
+ * pointer to the <17>.
+ *
+ * NOTE: The information from the third parameter in the FDT (GPIO_ACTIVE_LOW
in
+ * the example) is currently ignored.
+ */
+rtems_status_code imx_gpio_init_from_fdt_property_pointer(
+ struct imx_gpio_pin *pin,
+ const uint32_t *prop_pointer,
+ enum imx_gpio_mode mode,
+ const uint32_t **next_prop_pointer);
+
/**
* Initialize a GPIO pin from a FDT property.
*
diff --git a/bsps/arm/shared/pins/imx-gpio.c b/bsps/arm/shared/pins/imx-gpio.c
index 8b7d09e864..1e39822b93 100644
--- a/bsps/arm/shared/pins/imx-gpio.c
+++ b/bsps/arm/shared/pins/imx-gpio.c
@@ -191,12 +191,11 @@ static void imx_gpio_set_interrupt_mode(struct
imx_gpio_pin *pin, uint32_t mode)
}
}
-rtems_status_code imx_gpio_init_from_fdt_property (
+rtems_status_code imx_gpio_init_from_fdt_property_pointer (
struct imx_gpio_pin *pin,
- int node_offset,
- const char *property,
+ const uint32_t *prop_pointer,
enum imx_gpio_mode mode,
- size_t index
+ const uint32_t **next_prop_pointer
)
{
int len;
@@ -205,7 +204,6 @@ rtems_status_code imx_gpio_init_from_fdt_property (
const void *fdt;
uint32_t gpio_regs;
const unsigned pin_length_dwords = 3;
- const unsigned pin_length_bytes = (pin_length_dwords * sizeof(uint32_t));
uint32_t gpio_phandle;
uint32_t pin_nr;
int cfgnode;
@@ -213,16 +211,12 @@ rtems_status_code imx_gpio_init_from_fdt_property (
memset(pin, 0, sizeof(*pin));
fdt = bsp_fdt_get();
- val = fdt_getprop(fdt, node_offset, property, &len);
- if (val == NULL || (len % pin_length_bytes != 0) ||
- (index >= len / pin_length_bytes)) {
- sc = RTEMS_UNSATISFIED;
- }
if (sc == RTEMS_SUCCESSFUL) {
- pin_nr = fdt32_to_cpu(val[1 + index * pin_length_dwords]);
- gpio_phandle = fdt32_to_cpu(val[0 + index * pin_length_dwords]);
+ pin_nr = fdt32_to_cpu(prop_pointer[1]);
+ gpio_phandle = fdt32_to_cpu(prop_pointer[0]);
cfgnode = fdt_node_offset_by_phandle(fdt, gpio_phandle);
+ /* FIXME: Check compatible strings here. */
val = fdt_getprop(fdt, cfgnode, "reg", &len);
if (len > 0) {
gpio_regs = fdt32_to_cpu(val[0]);
@@ -239,6 +233,43 @@ rtems_status_code imx_gpio_init_from_fdt_property (
if (sc == RTEMS_SUCCESSFUL) {
imx_gpio_init(pin);
}
+ if (sc == RTEMS_SUCCESSFUL && next_prop_pointer != NULL) {
+ *next_prop_pointer = prop_pointer + pin_length_dwords;
+ }
+
+ return sc;
+}
+
+rtems_status_code imx_gpio_init_from_fdt_property (
+ struct imx_gpio_pin *pin,
+ int node_offset,
+ const char *property,
+ enum imx_gpio_mode mode,
+ size_t index
+)
+{
+ int len;
+ const uint32_t *val;
+ rtems_status_code sc = RTEMS_SUCCESSFUL;
+ const void *fdt;
+ const unsigned pin_length_dwords = 3;
+ const unsigned pin_length_bytes = pin_length_dwords * 4;
+
+ memset(pin, 0, sizeof(*pin));
+
+ fdt = bsp_fdt_get();
+ val = fdt_getprop(fdt, node_offset, property, &len);
+ if (val == NULL || (len % pin_length_bytes != 0) ||
+ (index >= len / pin_length_bytes)) {
+ sc = RTEMS_UNSATISFIED;
+ }
+ if (sc == RTEMS_SUCCESSFUL) {
+ sc = imx_gpio_init_from_fdt_property_pointer(
+ pin,
+ val + index * pin_length_dwords,
+ mode,
+ NULL);
+ }
return sc;
}
--
2.35.3
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