@@ -12,6 +12,8 @@
#include <dm/lists.h>
#include <dm/root.h>
+DECLARE_GLOBAL_DATA_PTR;
+
ulong clk_get_rate(struct udevice *dev)
{
struct clk_ops *ops = clk_get_ops(dev);
@@ -72,6 +74,32 @@ int clk_get_id(struct udevice *dev, int args_count, uint32_t *args)
return ops->get_id(dev, args_count, args);
}
+#if CONFIG_IS_ENABLED(OF_CONTROL)
+int clk_get_by_index(struct udevice *dev, int index, struct udevice **clk_devp)
+{
+ struct fdtdec_phandle_args args;
+ int ret;
+
+ assert(*clk_devp);
+ ret = fdtdec_parse_phandle_with_args(gd->fdt_blob, dev->of_offset,
+ "clocks", "#clock-cells", 0, index,
+ &args);
+ if (ret) {
+ debug("%s: fdtdec_parse_phandle_with_args failed: err=%d\n",
+ __func__, ret);
+ return ret;
+ }
+
+ ret = uclass_get_device_by_of_offset(UCLASS_CLK, args.node, clk_devp);
+ if (ret) {
+ debug("%s: uclass_get_device_by_of_offset failed: err=%d\n",
+ __func__, ret);
+ return ret;
+ }
+ return args.args_count > 0 ? args.args[0] : 0;
+}
+#endif
+
UCLASS_DRIVER(clk) = {
.id = UCLASS_CLK,
.name = "clk",
@@ -159,4 +159,21 @@ static inline int fdt_clk_get(const void *fdt, int nodeoffset, int index,
}
#endif
+#if CONFIG_IS_ENABLED(OF_CONTROL)
+/**
+ * clk_get_by_index() - look up a clock referenced by a device
+ *
+ * Parse a device's 'clocks' list, returning information on the indexed clock,
+ * ensuring that it is activated.
+ *
+ * @dev: Device containing the clock reference
+ * @index: Clock index to return (0 = first)
+ * @clk_devp: Returns clock device
+ * @return: Peripheral ID for the device to control. This is the first
+ * argument after the clock node phandle. If there is no arguemnt,
+ * returns 0. Return -ve error code on any error
+ */
+int clk_get_by_index(struct udevice *dev, int index, struct udevice **clk_devp);
+#endif
+
#endif /* _CLK_H_ */
Add a method which can locate a clock for a device, given its index. This uses the normal device tree bindings to return the clock device and the first argument which is normally used as a peripheral ID in U-Boot. Signed-off-by: Simon Glass <sjg@chromium.org> --- Changes in v3: - Use CONFIG_IS_ENABLED(OF_CONTROL) in C and header file Changes in v2: - Make the peripheral ID a return value - Add an assert for clk_devp - Make the function dependent on OF_CONTROL drivers/clk/clk-uclass.c | 28 ++++++++++++++++++++++++++++ include/clk.h | 17 +++++++++++++++++ 2 files changed, 45 insertions(+)