u-boot/drivers/clk/clk_fixed_rate.c
Masahiro Yamada b21e20b255 clk: add fixed rate clock driver
This commit intends to implement "fixed-clock" as in Linux.
(drivers/clk/clk-fixed-rate.c in Linux)

If you need a very simple clock to just provide fixed clock rate
like a crystal oscillator, you do not have to write a new driver.
This driver can support it.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
2016-01-21 19:46:47 -07:00

57 lines
1.3 KiB
C

/*
* Copyright (C) 2016 Masahiro Yamada <yamada.masahiro@socionext.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <clk.h>
#include <dm/device.h>
DECLARE_GLOBAL_DATA_PTR;
struct clk_fixed_rate {
unsigned long fixed_rate;
};
#define to_clk_fixed_rate(dev) ((struct clk_fixed_rate *)dev_get_platdata(dev))
static ulong clk_fixed_rate_get_rate(struct udevice *dev)
{
return to_clk_fixed_rate(dev)->fixed_rate;
}
static ulong clk_fixed_rate_get_periph_rate(struct udevice *dev, int periph)
{
return clk_fixed_rate_get_rate(dev);
}
const struct clk_ops clk_fixed_rate_ops = {
.get_rate = clk_fixed_rate_get_rate,
.get_periph_rate = clk_fixed_rate_get_periph_rate,
};
static int clk_fixed_rate_ofdata_to_platdata(struct udevice *dev)
{
to_clk_fixed_rate(dev)->fixed_rate =
fdtdec_get_int(gd->fdt_blob, dev->of_offset,
"clock-frequency", 0);
return 0;
}
static const struct udevice_id clk_fixed_rate_match[] = {
{
.compatible = "fixed-clock",
},
{ /* sentinel */ }
};
U_BOOT_DRIVER(clk_fixed_rate) = {
.name = "fixed_rate_clock",
.id = UCLASS_CLK,
.of_match = clk_fixed_rate_match,
.ofdata_to_platdata = clk_fixed_rate_ofdata_to_platdata,
.platdata_auto_alloc_size = sizeof(struct clk_fixed_rate),
.ops = &clk_fixed_rate_ops,
};