Commit 57251285 authored by Simon Glass's avatar Simon Glass
Browse files

dm: Add support for generic system controllers (syscon)



Many SoCs have a number of system controllers which are dealt with as a
group by a single driver. It is a pain to have to add lots of compatible
strings and/or separate drivers for each. Instead we can identify the
controllers by a number and request the address of the one we want.

Add a simple implementation of this which can be used by SoC driver code.
Signed-off-by: default avatarSimon Glass <sjg@chromium.org>
parent 6f98b750
......@@ -11,3 +11,4 @@ endif
obj-$(CONFIG_DM_DEVICE_REMOVE) += device-remove.o
obj-$(CONFIG_DM) += dump.o
obj-$(CONFIG_OF_CONTROL) += regmap.o
obj-$(CONFIG_OF_CONTROL) += syscon-uclass.o
/*
* Copyright (C) 2015 Google, Inc
* Written by Simon Glass <sjg@chromium.org>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <syscon.h>
#include <dm.h>
#include <errno.h>
#include <regmap.h>
#include <dm/device-internal.h>
#include <dm/lists.h>
#include <dm/root.h>
#include <linux/err.h>
struct regmap *syscon_get_regmap(struct udevice *dev)
{
struct syscon_uc_info *priv = dev_get_uclass_priv(dev);
return priv->regmap;
}
static int syscon_pre_probe(struct udevice *dev)
{
struct syscon_uc_info *priv = dev_get_uclass_priv(dev);
return regmap_init_mem(dev, &priv->regmap);
}
struct regmap *syscon_get_regmap_by_driver_data(ulong driver_data)
{
struct udevice *dev;
struct uclass *uc;
int ret;
ret = uclass_get(UCLASS_SYSCON, &uc);
if (ret)
return ERR_PTR(ret);
uclass_foreach_dev(dev, uc) {
if (dev->driver_data == driver_data) {
struct syscon_uc_info *priv;
int ret;
ret = device_probe(dev);
if (ret)
return ERR_PTR(ret);
priv = dev_get_uclass_priv(dev);
return priv->regmap;
}
}
return ERR_PTR(-ENOENT);
}
void *syscon_get_first_range(ulong driver_data)
{
struct regmap *map;
map = syscon_get_regmap_by_driver_data(driver_data);
if (IS_ERR(map))
return map;
return regmap_get_range(map, 0);
}
UCLASS_DRIVER(syscon) = {
.id = UCLASS_SYSCON,
.name = "syscon",
.per_device_auto_alloc_size = sizeof(struct syscon_uc_info),
.pre_probe = syscon_pre_probe,
};
......@@ -46,6 +46,7 @@ enum uclass_id {
UCLASS_SPI, /* SPI bus */
UCLASS_SPI_FLASH, /* SPI flash */
UCLASS_SPI_GENERIC, /* Generic SPI flash target */
UCLASS_SYSCON, /* System configuration device */
UCLASS_THERMAL, /* Thermal sensor */
UCLASS_USB, /* USB bus */
UCLASS_USB_DEV_GENERIC, /* USB generic device */
......
/*
* Copyright (c) 2015 Google, Inc
* Written by Simon Glass <sjg@chromium.org>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#ifndef __SYSCON_H
#define __SYSCON_H
/**
* struct syscon_uc_info - Information stored by the syscon UCLASS_UCLASS
*
* @regmap: Register map for this controller
*/
struct syscon_uc_info {
struct regmap *regmap;
};
/* So far there are no ops so this is a placeholder */
struct syscon_ops {
};
#define syscon_get_ops(dev) ((struct syscon_ops *)(dev)->driver->ops)
/**
* syscon_get_regmap() - Get access to a register map
*
* @dev: Device to check (UCLASS_SCON)
* @info: Returns regmap for the device
* @return 0 if OK, -ve on error
*/
struct regmap *syscon_get_regmap(struct udevice *dev);
/**
* syscon_get_regmap_by_driver_data() - Look up a controller by its ID
*
* Each system controller can be accessed by its driver data, which is
* assumed to be unique through the scope of all system controllers that
* are in use. This function looks up the regmap given this driver data.
*
* @driver_data: Driver data value to look up
* @return register map correponding to @driver_data, or -ve error code
*/
struct regmap *syscon_get_regmap_by_driver_data(ulong driver_data);
/**
* syscon_get_first_range() - get the first memory range from a syscon regmap
*
* @driver_data: Driver data value to look up
* @return first region of register map correponding to @driver_data, or
* -ve error code
*/
void *syscon_get_first_range(ulong driver_data);
#endif
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment