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 ---
drivers/clk/clk-uclass.c | 28 ++++++++++++++++++++++++++++ include/clk.h | 15 +++++++++++++++ 2 files changed, 43 insertions(+)
diff --git a/drivers/clk/clk-uclass.c b/drivers/clk/clk-uclass.c index 8078b0f..a205b26 100644 --- a/drivers/clk/clk-uclass.c +++ b/drivers/clk/clk-uclass.c @@ -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); @@ -62,6 +64,32 @@ int clk_get_id(struct udevice *dev, int args_count, uint32_t *args) return ops->get_id(dev, args_count, args); }
+int clk_get_by_index(struct udevice *dev, int index, struct udevice **clk_devp, + int *periphp) +{ + struct fdtdec_phandle_args args; + int ret; + + 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; + } + *periphp = args.args_count > 0 ? args.args[0] : -1; + + return 0; +} + UCLASS_DRIVER(clk) = { .id = UCLASS_CLK, .name = "clk", diff --git a/include/clk.h b/include/clk.h index ce2db41..b77c788 100644 --- a/include/clk.h +++ b/include/clk.h @@ -150,4 +150,19 @@ static inline int fdt_clk_get(const void *fdt, int nodeoffset, int index, } #endif
+/** + * 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 + * @periphp: Returns peripheral ID for the device to control. This is the + * first argument after the clock node phandle. + * @return 0 if OK, or -ve error code + */ +int clk_get_by_index(struct udevice *dev, int index, struct udevice **clk_devp, + int *periphp); #endif /* _CLK_H_ */