1// SPDX-License-Identifier: GPL-2.0
  2
  3#include <linux/errno.h>
  4#include <linux/mdio.h>
  5#include <linux/module.h>
  6#include <linux/regmap.h>
  7
  8#define REGVAL_MASK		GENMASK(15, 0)
  9#define REGNUM_C22_MASK		GENMASK(4, 0)
 10/* Clause-45 mask includes the device type (5 bit) and actual register number (16 bit) */
 11#define REGNUM_C45_MASK		GENMASK(20, 0)
 12
 13static int regmap_mdio_read(struct mdio_device *mdio_dev, u32 reg, unsigned int *val)
 14{
 15	int ret;
 16
 17	ret = mdiodev_read(mdio_dev, reg);
 18	if (ret < 0)
 19		return ret;
 20
 21	*val = ret & REGVAL_MASK;
 22	return 0;
 23}
 24
 25static int regmap_mdio_write(struct mdio_device *mdio_dev, u32 reg, unsigned int val)
 26{
 27	return mdiodev_write(mdio_dev, reg, val);
 28}
 29
 30static int regmap_mdio_c22_read(void *context, unsigned int reg, unsigned int *val)
 31{
 32	struct mdio_device *mdio_dev = context;
 33
 34	if (unlikely(reg & ~REGNUM_C22_MASK))
 35		return -ENXIO;
 36
 37	return regmap_mdio_read(mdio_dev, reg, val);
 38}
 39
 40static int regmap_mdio_c22_write(void *context, unsigned int reg, unsigned int val)
 41{
 42	struct mdio_device *mdio_dev = context;
 43
 44	if (unlikely(reg & ~REGNUM_C22_MASK))
 45		return -ENXIO;
 46
 47	return mdiodev_write(mdio_dev, reg, val);
 48}
 49
 50static const struct regmap_bus regmap_mdio_c22_bus = {
 51	.reg_write = regmap_mdio_c22_write,
 52	.reg_read = regmap_mdio_c22_read,
 53};
 54
 55static int regmap_mdio_c45_read(void *context, unsigned int reg, unsigned int *val)
 56{
 57	struct mdio_device *mdio_dev = context;
 58
 59	if (unlikely(reg & ~REGNUM_C45_MASK))
 60		return -ENXIO;
 61
 62	return regmap_mdio_read(mdio_dev, MII_ADDR_C45 | reg, val);
 63}
 64
 65static int regmap_mdio_c45_write(void *context, unsigned int reg, unsigned int val)
 66{
 67	struct mdio_device *mdio_dev = context;
 68
 69	if (unlikely(reg & ~REGNUM_C45_MASK))
 70		return -ENXIO;
 71
 72	return regmap_mdio_write(mdio_dev, MII_ADDR_C45 | reg, val);
 73}
 74
 75static const struct regmap_bus regmap_mdio_c45_bus = {
 76	.reg_write = regmap_mdio_c45_write,
 77	.reg_read = regmap_mdio_c45_read,
 78};
 79
 80struct regmap *__regmap_init_mdio(struct mdio_device *mdio_dev,
 81	const struct regmap_config *config, struct lock_class_key *lock_key,
 82	const char *lock_name)
 83{
 84	const struct regmap_bus *bus;
 85
 86	if (config->reg_bits == 5 && config->val_bits == 16)
 87		bus = &regmap_mdio_c22_bus;
 88	else if (config->reg_bits == 21 && config->val_bits == 16)
 89		bus = &regmap_mdio_c45_bus;
 90	else
 91		return ERR_PTR(-EOPNOTSUPP);
 92
 93	return __regmap_init(&mdio_dev->dev, bus, mdio_dev, config, lock_key, lock_name);
 94}
 95EXPORT_SYMBOL_GPL(__regmap_init_mdio);
 96
 97struct regmap *__devm_regmap_init_mdio(struct mdio_device *mdio_dev,
 98	const struct regmap_config *config, struct lock_class_key *lock_key,
 99	const char *lock_name)
100{
101	const struct regmap_bus *bus;
102
103	if (config->reg_bits == 5 && config->val_bits == 16)
104		bus = &regmap_mdio_c22_bus;
105	else if (config->reg_bits == 21 && config->val_bits == 16)
106		bus = &regmap_mdio_c45_bus;
107	else
108		return ERR_PTR(-EOPNOTSUPP);
109
110	return __devm_regmap_init(&mdio_dev->dev, bus, mdio_dev, config, lock_key, lock_name);
111}
112EXPORT_SYMBOL_GPL(__devm_regmap_init_mdio);
113
114MODULE_AUTHOR("Sander Vanheule <sander@svanheule.net>");
115MODULE_DESCRIPTION("Regmap MDIO Module");
116MODULE_LICENSE("GPL v2");