linux/drivers/base/regmap/regmap-mdio.c
Sander Vanheule 0df0240946
regmap: mdio: Reject invalid addresses
When an invalid register offset is provided, the upper bits are silently
discarded. Change this to return -ENXIO instead, to help catch potential
bugs.

Signed-off-by: Sander Vanheule <sander@svanheule.net>
Link: https://lore.kernel.org/r/047007e0e9fb596480829f11f8c7e6281d235c70.1623244066.git.sander@svanheule.net
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-06-14 15:00:29 +01:00

117 lines
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/errno.h>
#include <linux/mdio.h>
#include <linux/module.h>
#include <linux/regmap.h>
#define REGVAL_MASK GENMASK(15, 0)
#define REGNUM_C22_MASK GENMASK(4, 0)
/* Clause-45 mask includes the device type (5 bit) and actual register number (16 bit) */
#define REGNUM_C45_MASK GENMASK(20, 0)
static int regmap_mdio_read(struct mdio_device *mdio_dev, u32 reg, unsigned int *val)
{
int ret;
ret = mdiobus_read(mdio_dev->bus, mdio_dev->addr, reg);
if (ret < 0)
return ret;
*val = ret & REGVAL_MASK;
return 0;
}
static int regmap_mdio_write(struct mdio_device *mdio_dev, u32 reg, unsigned int val)
{
return mdiobus_write(mdio_dev->bus, mdio_dev->addr, reg, val);
}
static int regmap_mdio_c22_read(void *context, unsigned int reg, unsigned int *val)
{
struct mdio_device *mdio_dev = context;
if (unlikely(reg & ~REGNUM_C22_MASK))
return -ENXIO;
return regmap_mdio_read(mdio_dev, reg, val);
}
static int regmap_mdio_c22_write(void *context, unsigned int reg, unsigned int val)
{
struct mdio_device *mdio_dev = context;
if (unlikely(reg & ~REGNUM_C22_MASK))
return -ENXIO;
return mdiobus_write(mdio_dev->bus, mdio_dev->addr, reg, val);
}
static const struct regmap_bus regmap_mdio_c22_bus = {
.reg_write = regmap_mdio_c22_write,
.reg_read = regmap_mdio_c22_read,
};
static int regmap_mdio_c45_read(void *context, unsigned int reg, unsigned int *val)
{
struct mdio_device *mdio_dev = context;
if (unlikely(reg & ~REGNUM_C45_MASK))
return -ENXIO;
return regmap_mdio_read(mdio_dev, MII_ADDR_C45 | reg, val);
}
static int regmap_mdio_c45_write(void *context, unsigned int reg, unsigned int val)
{
struct mdio_device *mdio_dev = context;
if (unlikely(reg & ~REGNUM_C45_MASK))
return -ENXIO;
return regmap_mdio_write(mdio_dev, MII_ADDR_C45 | reg, val);
}
static const struct regmap_bus regmap_mdio_c45_bus = {
.reg_write = regmap_mdio_c45_write,
.reg_read = regmap_mdio_c45_read,
};
struct regmap *__regmap_init_mdio(struct mdio_device *mdio_dev,
const struct regmap_config *config, struct lock_class_key *lock_key,
const char *lock_name)
{
const struct regmap_bus *bus;
if (config->reg_bits == 5 && config->val_bits == 16)
bus = &regmap_mdio_c22_bus;
else if (config->reg_bits == 21 && config->val_bits == 16)
bus = &regmap_mdio_c45_bus;
else
return ERR_PTR(-EOPNOTSUPP);
return __regmap_init(&mdio_dev->dev, bus, mdio_dev, config, lock_key, lock_name);
}
EXPORT_SYMBOL_GPL(__regmap_init_mdio);
struct regmap *__devm_regmap_init_mdio(struct mdio_device *mdio_dev,
const struct regmap_config *config, struct lock_class_key *lock_key,
const char *lock_name)
{
const struct regmap_bus *bus;
if (config->reg_bits == 5 && config->val_bits == 16)
bus = &regmap_mdio_c22_bus;
else if (config->reg_bits == 21 && config->val_bits == 16)
bus = &regmap_mdio_c45_bus;
else
return ERR_PTR(-EOPNOTSUPP);
return __devm_regmap_init(&mdio_dev->dev, bus, mdio_dev, config, lock_key, lock_name);
}
EXPORT_SYMBOL_GPL(__devm_regmap_init_mdio);
MODULE_AUTHOR("Sander Vanheule <sander@svanheule.net>");
MODULE_DESCRIPTION("Regmap MDIO Module");
MODULE_LICENSE("GPL v2");