mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-19 03:08:31 +00:00
89c1e2da78
A reset controller is a hardware module that controls reset signals that affect other hardware modules or chips. This patch defines a standard API that connects reset clients (i.e. the drivers for devices affected by reset signals) to drivers for reset controllers/providers. Initially, DT is the only supported method for connecting the two. The DT binding specification (reset.txt) was taken from Linux kernel v4.5's Documentation/devicetree/bindings/reset/reset.txt. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Simon Glass <sjg@chromium.org>
131 lines
2.8 KiB
C
131 lines
2.8 KiB
C
/*
|
|
* Copyright (c) 2016, NVIDIA CORPORATION.
|
|
*
|
|
* SPDX-License-Identifier: GPL-2.0
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <dm.h>
|
|
#include <fdtdec.h>
|
|
#include <reset.h>
|
|
#include <reset-uclass.h>
|
|
|
|
DECLARE_GLOBAL_DATA_PTR;
|
|
|
|
static inline struct reset_ops *reset_dev_ops(struct udevice *dev)
|
|
{
|
|
return (struct reset_ops *)dev->driver->ops;
|
|
}
|
|
|
|
static int reset_of_xlate_default(struct reset_ctl *reset_ctl,
|
|
struct fdtdec_phandle_args *args)
|
|
{
|
|
debug("%s(reset_ctl=%p)\n", __func__, reset_ctl);
|
|
|
|
if (args->args_count != 1) {
|
|
debug("Invaild args_count: %d\n", args->args_count);
|
|
return -EINVAL;
|
|
}
|
|
|
|
reset_ctl->id = args->args[0];
|
|
|
|
return 0;
|
|
}
|
|
|
|
int reset_get_by_index(struct udevice *dev, int index,
|
|
struct reset_ctl *reset_ctl)
|
|
{
|
|
struct fdtdec_phandle_args args;
|
|
int ret;
|
|
struct udevice *dev_reset;
|
|
struct reset_ops *ops;
|
|
|
|
debug("%s(dev=%p, index=%d, reset_ctl=%p)\n", __func__, dev, index,
|
|
reset_ctl);
|
|
|
|
ret = fdtdec_parse_phandle_with_args(gd->fdt_blob, dev->of_offset,
|
|
"resets", "#reset-cells", 0,
|
|
index, &args);
|
|
if (ret) {
|
|
debug("%s: fdtdec_parse_phandle_with_args failed: %d\n",
|
|
__func__, ret);
|
|
return ret;
|
|
}
|
|
|
|
ret = uclass_get_device_by_of_offset(UCLASS_RESET, args.node,
|
|
&dev_reset);
|
|
if (ret) {
|
|
debug("%s: uclass_get_device_by_of_offset failed: %d\n",
|
|
__func__, ret);
|
|
return ret;
|
|
}
|
|
ops = reset_dev_ops(dev_reset);
|
|
|
|
reset_ctl->dev = dev_reset;
|
|
if (ops->of_xlate)
|
|
ret = ops->of_xlate(reset_ctl, &args);
|
|
else
|
|
ret = reset_of_xlate_default(reset_ctl, &args);
|
|
if (ret) {
|
|
debug("of_xlate() failed: %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
ret = ops->request(reset_ctl);
|
|
if (ret) {
|
|
debug("ops->request() failed: %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int reset_get_by_name(struct udevice *dev, const char *name,
|
|
struct reset_ctl *reset_ctl)
|
|
{
|
|
int index;
|
|
|
|
debug("%s(dev=%p, name=%s, reset_ctl=%p)\n", __func__, dev, name,
|
|
reset_ctl);
|
|
|
|
index = fdt_find_string(gd->fdt_blob, dev->of_offset, "reset-names",
|
|
name);
|
|
if (index < 0) {
|
|
debug("fdt_find_string() failed: %d\n", index);
|
|
return index;
|
|
}
|
|
|
|
return reset_get_by_index(dev, index, reset_ctl);
|
|
}
|
|
|
|
int reset_free(struct reset_ctl *reset_ctl)
|
|
{
|
|
struct reset_ops *ops = reset_dev_ops(reset_ctl->dev);
|
|
|
|
debug("%s(reset_ctl=%p)\n", __func__, reset_ctl);
|
|
|
|
return ops->free(reset_ctl);
|
|
}
|
|
|
|
int reset_assert(struct reset_ctl *reset_ctl)
|
|
{
|
|
struct reset_ops *ops = reset_dev_ops(reset_ctl->dev);
|
|
|
|
debug("%s(reset_ctl=%p)\n", __func__, reset_ctl);
|
|
|
|
return ops->rst_assert(reset_ctl);
|
|
}
|
|
|
|
int reset_deassert(struct reset_ctl *reset_ctl)
|
|
{
|
|
struct reset_ops *ops = reset_dev_ops(reset_ctl->dev);
|
|
|
|
debug("%s(reset_ctl=%p)\n", __func__, reset_ctl);
|
|
|
|
return ops->rst_deassert(reset_ctl);
|
|
}
|
|
|
|
UCLASS_DRIVER(reset) = {
|
|
.id = UCLASS_RESET,
|
|
.name = "reset",
|
|
};
|