u-boot/drivers/core/syscon-uclass.c
Patrick Delaunay de5bab9c59 syscon: update syscon_node_to_regmap to use the DM functions
+ Update the function syscon_node_to_regmap() to force bound on
  syscon uclass and directly use the list of device from DM.
+ Remove the static list syscon_list.

This patch avoid issue (crash) when syscon_node_to_regmap() is called
before and after reallocation (list content is invalid).

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
2018-12-15 11:49:56 -05:00

176 lines
3.9 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2015 Google, Inc
* Written by Simon Glass <sjg@chromium.org>
*/
#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>
/*
* Caution:
* This API requires the given device has alerady been bound to syscon driver.
* For example,
* compatible = "syscon", "simple-mfd";
* works, but
* compatible = "simple-mfd", "syscon";
* does not. The behavior is different from Linux.
*/
struct regmap *syscon_get_regmap(struct udevice *dev)
{
struct syscon_uc_info *priv;
if (device_get_uclass_id(dev) != UCLASS_SYSCON)
return ERR_PTR(-ENOEXEC);
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);
/*
* With OF_PLATDATA we really have no way of knowing the format of
* the device-specific platform data. So we assume that it starts with
* a 'reg' member, and this holds a single address and size. Drivers
* using OF_PLATDATA will need to ensure that this is true.
*/
#if CONFIG_IS_ENABLED(OF_PLATDATA)
struct syscon_base_platdata *plat = dev_get_platdata(dev);
return regmap_init_mem_platdata(dev, plat->reg, ARRAY_SIZE(plat->reg),
&priv->regmap);
#else
return regmap_init_mem(dev_ofnode(dev), &priv->regmap);
#endif
}
struct regmap *syscon_regmap_lookup_by_phandle(struct udevice *dev,
const char *name)
{
struct udevice *syscon;
struct regmap *r;
int err;
err = uclass_get_device_by_phandle(UCLASS_SYSCON, dev,
name, &syscon);
if (err) {
dev_dbg(dev, "unable to find syscon device\n");
return ERR_PTR(err);
}
r = syscon_get_regmap(syscon);
if (!r) {
dev_dbg(dev, "unable to find regmap\n");
return ERR_PTR(-ENODEV);
}
return r;
}
int syscon_get_by_driver_data(ulong driver_data, struct udevice **devp)
{
struct udevice *dev;
struct uclass *uc;
int ret;
*devp = NULL;
ret = uclass_get(UCLASS_SYSCON, &uc);
if (ret)
return ret;
uclass_foreach_dev(dev, uc) {
if (dev->driver_data == driver_data) {
*devp = dev;
return device_probe(dev);
}
}
return -ENODEV;
}
struct regmap *syscon_get_regmap_by_driver_data(ulong driver_data)
{
struct syscon_uc_info *priv;
struct udevice *dev;
int ret;
ret = syscon_get_by_driver_data(driver_data, &dev);
if (ret)
return ERR_PTR(ret);
priv = dev_get_uclass_priv(dev);
return priv->regmap;
}
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,
};
static const struct udevice_id generic_syscon_ids[] = {
{ .compatible = "syscon" },
{ }
};
U_BOOT_DRIVER(generic_syscon) = {
.name = "syscon",
.id = UCLASS_SYSCON,
#if !CONFIG_IS_ENABLED(OF_PLATDATA)
.bind = dm_scan_fdt_dev,
#endif
.of_match = generic_syscon_ids,
};
/*
* Linux-compatible syscon-to-regmap
* The syscon node can be bound to another driver, but still works
* as a syscon provider.
*/
struct regmap *syscon_node_to_regmap(ofnode node)
{
struct udevice *dev, *parent;
int ret;
if (!uclass_get_device_by_ofnode(UCLASS_SYSCON, node, &dev))
return syscon_get_regmap(dev);
if (!ofnode_device_is_compatible(node, "syscon"))
return ERR_PTR(-EINVAL);
/* bound to driver with same ofnode or to root if not found */
if (device_find_global_by_ofnode(node, &parent))
parent = dm_root();
/* force bound to syscon class */
ret = device_bind_driver_to_node(parent, "syscon",
ofnode_get_name(node),
node, &dev);
if (ret)
return ERR_PTR(ret);
ret = device_probe(dev);
if (ret)
return ERR_PTR(ret);
return syscon_get_regmap(dev);
}