u-boot/drivers/clk/clk-uclass.c
Simon Glass e70cc43831 dm: clk: Add support for decoding clocks from the device tree
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>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2016-01-21 19:47:29 -07:00

96 lines
1.9 KiB
C

/*
* Copyright (C) 2015 Google, Inc
* Written by Simon Glass <sjg@chromium.org>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <clk.h>
#include <dm.h>
#include <errno.h>
#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);
if (!ops->get_rate)
return -ENOSYS;
return ops->get_rate(dev);
}
ulong clk_set_rate(struct udevice *dev, ulong rate)
{
struct clk_ops *ops = clk_get_ops(dev);
if (!ops->set_rate)
return -ENOSYS;
return ops->set_rate(dev, rate);
}
int clk_enable(struct udevice *dev, int periph)
{
struct clk_ops *ops = clk_get_ops(dev);
if (!ops->enable)
return -ENOSYS;
return ops->enable(dev, periph);
}
ulong clk_get_periph_rate(struct udevice *dev, int periph)
{
struct clk_ops *ops = clk_get_ops(dev);
if (!ops->get_periph_rate)
return -ENOSYS;
return ops->get_periph_rate(dev, periph);
}
ulong clk_set_periph_rate(struct udevice *dev, int periph, ulong rate)
{
struct clk_ops *ops = clk_get_ops(dev);
if (!ops->set_periph_rate)
return -ENOSYS;
return ops->set_periph_rate(dev, periph, rate);
}
#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",
};