1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) 2017 Pengutronix, Juergen Borleis <kernel@pengutronix.de>
  4 *
  5 * Partially based on a patch from
  6 * Copyright (c) 2014 Stefan Roese <sr@denx.de>
  7 */
  8#include <linux/kernel.h>
  9#include <linux/module.h>
 10#include <linux/mdio.h>
 11#include <linux/phy.h>
 12#include <linux/of.h>
 13
 14#include "lan9303.h"
 15
 16/* Generate phy-addr and -reg from the input address */
 17#define PHY_ADDR(x) ((((x) >> 6) + 0x10) & 0x1f)
 18#define PHY_REG(x) (((x) >> 1) & 0x1f)
 19
 20struct lan9303_mdio {
 21	struct mdio_device *device;
 22	struct lan9303 chip;
 23};
 24
 25static void lan9303_mdio_real_write(struct mdio_device *mdio, int reg, u16 val)
 26{
 27	mdio->bus->write(mdio->bus, PHY_ADDR(reg), PHY_REG(reg), val);
 28}
 29
 30static int lan9303_mdio_write(void *ctx, uint32_t reg, uint32_t val)
 31{
 32	struct lan9303_mdio *sw_dev = (struct lan9303_mdio *)ctx;
 33
 34	reg <<= 2; /* reg num to offset */
 35	mutex_lock_nested(&sw_dev->device->bus->mdio_lock, MDIO_MUTEX_NESTED);
 36	lan9303_mdio_real_write(sw_dev->device, reg, val & 0xffff);
 37	lan9303_mdio_real_write(sw_dev->device, reg + 2, (val >> 16) & 0xffff);
 38	mutex_unlock(&sw_dev->device->bus->mdio_lock);
 39
 40	return 0;
 41}
 42
 43static u16 lan9303_mdio_real_read(struct mdio_device *mdio, int reg)
 44{
 45	return mdio->bus->read(mdio->bus, PHY_ADDR(reg), PHY_REG(reg));
 46}
 47
 48static int lan9303_mdio_read(void *ctx, uint32_t reg, uint32_t *val)
 49{
 50	struct lan9303_mdio *sw_dev = (struct lan9303_mdio *)ctx;
 51
 52	reg <<= 2; /* reg num to offset */
 53	mutex_lock_nested(&sw_dev->device->bus->mdio_lock, MDIO_MUTEX_NESTED);
 54	*val = lan9303_mdio_real_read(sw_dev->device, reg);
 55	*val |= (lan9303_mdio_real_read(sw_dev->device, reg + 2) << 16);
 56	mutex_unlock(&sw_dev->device->bus->mdio_lock);
 57
 58	return 0;
 59}
 60
 61static int lan9303_mdio_phy_write(struct lan9303 *chip, int phy, int reg,
 62				  u16 val)
 63{
 64	struct lan9303_mdio *sw_dev = dev_get_drvdata(chip->dev);
 65
 66	return mdiobus_write_nested(sw_dev->device->bus, phy, reg, val);
 67}
 68
 69static int lan9303_mdio_phy_read(struct lan9303 *chip, int phy,  int reg)
 70{
 71	struct lan9303_mdio *sw_dev = dev_get_drvdata(chip->dev);
 72
 73	return mdiobus_read_nested(sw_dev->device->bus, phy, reg);
 74}
 75
 76static const struct lan9303_phy_ops lan9303_mdio_phy_ops = {
 77	.phy_read = lan9303_mdio_phy_read,
 78	.phy_write = lan9303_mdio_phy_write,
 79};
 80
 81static const struct regmap_config lan9303_mdio_regmap_config = {
 82	.reg_bits = 8,
 83	.val_bits = 32,
 84	.reg_stride = 1,
 85	.can_multi_write = true,
 86	.max_register = 0x0ff, /* address bits 0..1 are not used */
 87	.reg_format_endian = REGMAP_ENDIAN_LITTLE,
 88
 89	.volatile_table = &lan9303_register_set,
 90	.wr_table = &lan9303_register_set,
 91	.rd_table = &lan9303_register_set,
 92
 93	.reg_read = lan9303_mdio_read,
 94	.reg_write = lan9303_mdio_write,
 95
 96	.cache_type = REGCACHE_NONE,
 97};
 98
 99static int lan9303_mdio_probe(struct mdio_device *mdiodev)
100{
101	struct lan9303_mdio *sw_dev;
102	int ret;
103
104	sw_dev = devm_kzalloc(&mdiodev->dev, sizeof(struct lan9303_mdio),
105			      GFP_KERNEL);
106	if (!sw_dev)
107		return -ENOMEM;
108
109	sw_dev->chip.regmap = devm_regmap_init(&mdiodev->dev, NULL, sw_dev,
110					       &lan9303_mdio_regmap_config);
111	if (IS_ERR(sw_dev->chip.regmap)) {
112		ret = PTR_ERR(sw_dev->chip.regmap);
113		dev_err(&mdiodev->dev, "regmap init failed: %d\n", ret);
114		return ret;
115	}
116
117	/* link forward and backward */
118	sw_dev->device = mdiodev;
119	dev_set_drvdata(&mdiodev->dev, sw_dev);
120	sw_dev->chip.dev = &mdiodev->dev;
121
122	sw_dev->chip.ops = &lan9303_mdio_phy_ops;
123
124	ret = lan9303_probe(&sw_dev->chip, mdiodev->dev.of_node);
125	if (ret != 0)
126		return ret;
127
128	dev_info(&mdiodev->dev, "LAN9303 MDIO driver loaded successfully\n");
129
130	return 0;
131}
132
133static void lan9303_mdio_remove(struct mdio_device *mdiodev)
134{
135	struct lan9303_mdio *sw_dev = dev_get_drvdata(&mdiodev->dev);
136
137	if (!sw_dev)
138		return;
139
140	lan9303_remove(&sw_dev->chip);
141}
142
143static void lan9303_mdio_shutdown(struct mdio_device *mdiodev)
144{
145	struct lan9303_mdio *sw_dev = dev_get_drvdata(&mdiodev->dev);
146
147	if (!sw_dev)
148		return;
149
150	lan9303_shutdown(&sw_dev->chip);
151
152	dev_set_drvdata(&mdiodev->dev, NULL);
153}
154
155/*-------------------------------------------------------------------------*/
156
157static const struct of_device_id lan9303_mdio_of_match[] = {
158	{ .compatible = "smsc,lan9303-mdio" },
159	{ .compatible = "microchip,lan9354-mdio" },
160	{ /* sentinel */ },
161};
162MODULE_DEVICE_TABLE(of, lan9303_mdio_of_match);
163
164static struct mdio_driver lan9303_mdio_driver = {
165	.mdiodrv.driver = {
166		.name = "LAN9303_MDIO",
167		.of_match_table = lan9303_mdio_of_match,
168	},
169	.probe  = lan9303_mdio_probe,
170	.remove = lan9303_mdio_remove,
171	.shutdown = lan9303_mdio_shutdown,
172};
173mdio_module_driver(lan9303_mdio_driver);
174
175MODULE_AUTHOR("Stefan Roese <sr@denx.de>, Juergen Borleis <kernel@pengutronix.de>");
176MODULE_DESCRIPTION("Driver for SMSC/Microchip LAN9303 three port ethernet switch in MDIO managed mode");
177MODULE_LICENSE("GPL v2");