1/*
  2 * Marvell 88e6xxx Ethernet switch PHY and PPU support
  3 *
  4 * Copyright (c) 2008 Marvell Semiconductor
  5 *
  6 * Copyright (c) 2017 Andrew Lunn <andrew@lunn.ch>
  7 *
  8 * This program is free software; you can redistribute it and/or modify
  9 * it under the terms of the GNU General Public License as published by
 10 * the Free Software Foundation; either version 2 of the License, or
 11 * (at your option) any later version.
 12 */
 13
 14#include <linux/mdio.h>
 15#include <linux/module.h>
 16
 17#include "chip.h"
 18#include "phy.h"
 19
 20int mv88e6165_phy_read(struct mv88e6xxx_chip *chip, struct mii_bus *bus,
 21		       int addr, int reg, u16 *val)
 22{
 23	return mv88e6xxx_read(chip, addr, reg, val);
 24}
 25
 26int mv88e6165_phy_write(struct mv88e6xxx_chip *chip, struct mii_bus *bus,
 27			int addr, int reg, u16 val)
 28{
 29	return mv88e6xxx_write(chip, addr, reg, val);
 30}
 31
 32int mv88e6xxx_phy_read(struct mv88e6xxx_chip *chip, int phy, int reg, u16 *val)
 33{
 34	int addr = phy; /* PHY devices addresses start at 0x0 */
 35	struct mii_bus *bus;
 36
 37	bus = mv88e6xxx_default_mdio_bus(chip);
 38	if (!bus)
 39		return -EOPNOTSUPP;
 40
 41	if (!chip->info->ops->phy_read)
 42		return -EOPNOTSUPP;
 43
 44	return chip->info->ops->phy_read(chip, bus, addr, reg, val);
 45}
 46
 47int mv88e6xxx_phy_write(struct mv88e6xxx_chip *chip, int phy, int reg, u16 val)
 48{
 49	int addr = phy; /* PHY devices addresses start at 0x0 */
 50	struct mii_bus *bus;
 51
 52	bus = mv88e6xxx_default_mdio_bus(chip);
 53	if (!bus)
 54		return -EOPNOTSUPP;
 55
 56	if (!chip->info->ops->phy_write)
 57		return -EOPNOTSUPP;
 58
 59	return chip->info->ops->phy_write(chip, bus, addr, reg, val);
 60}
 61
 62static int mv88e6xxx_phy_page_get(struct mv88e6xxx_chip *chip, int phy, u8 page)
 63{
 64	return mv88e6xxx_phy_write(chip, phy, MV88E6XXX_PHY_PAGE, page);
 65}
 66
 67static void mv88e6xxx_phy_page_put(struct mv88e6xxx_chip *chip, int phy)
 68{
 69	int err;
 70
 71	/* Restore PHY page Copper 0x0 for access via the registered
 72	 * MDIO bus
 73	 */
 74	err = mv88e6xxx_phy_write(chip, phy, MV88E6XXX_PHY_PAGE,
 75				  MV88E6XXX_PHY_PAGE_COPPER);
 76	if (unlikely(err)) {
 77		dev_err(chip->dev,
 78			"failed to restore PHY %d page Copper (%d)\n",
 79			phy, err);
 80	}
 81}
 82
 83int mv88e6xxx_phy_page_read(struct mv88e6xxx_chip *chip, int phy,
 84			    u8 page, int reg, u16 *val)
 85{
 86	int err;
 87
 88	/* There is no paging for registers 22 */
 89	if (reg == MV88E6XXX_PHY_PAGE)
 90		return -EINVAL;
 91
 92	err = mv88e6xxx_phy_page_get(chip, phy, page);
 93	if (!err) {
 94		err = mv88e6xxx_phy_read(chip, phy, reg, val);
 95		mv88e6xxx_phy_page_put(chip, phy);
 96	}
 97
 98	return err;
 99}
100
101int mv88e6xxx_phy_page_write(struct mv88e6xxx_chip *chip, int phy,
102			     u8 page, int reg, u16 val)
103{
104	int err;
105
106	/* There is no paging for registers 22 */
107	if (reg == MV88E6XXX_PHY_PAGE)
108		return -EINVAL;
109
110	err = mv88e6xxx_phy_page_get(chip, phy, page);
111	if (!err) {
112		err = mv88e6xxx_phy_write(chip, phy, MV88E6XXX_PHY_PAGE, page);
113		mv88e6xxx_phy_page_put(chip, phy);
114	}
115
116	return err;
117}
118
119static int mv88e6xxx_phy_ppu_disable(struct mv88e6xxx_chip *chip)
120{
121	if (!chip->info->ops->ppu_disable)
122		return 0;
123
124	return chip->info->ops->ppu_disable(chip);
125}
126
127static int mv88e6xxx_phy_ppu_enable(struct mv88e6xxx_chip *chip)
128{
129	if (!chip->info->ops->ppu_enable)
130		return 0;
131
132	return chip->info->ops->ppu_enable(chip);
133}
134
135static void mv88e6xxx_phy_ppu_reenable_work(struct work_struct *ugly)
136{
137	struct mv88e6xxx_chip *chip;
138
139	chip = container_of(ugly, struct mv88e6xxx_chip, ppu_work);
140
141	mutex_lock(&chip->reg_lock);
142
143	if (mutex_trylock(&chip->ppu_mutex)) {
144		if (mv88e6xxx_phy_ppu_enable(chip) == 0)
145			chip->ppu_disabled = 0;
146		mutex_unlock(&chip->ppu_mutex);
147	}
148
149	mutex_unlock(&chip->reg_lock);
150}
151
152static void mv88e6xxx_phy_ppu_reenable_timer(struct timer_list *t)
153{
154	struct mv88e6xxx_chip *chip = from_timer(chip, t, ppu_timer);
155
156	schedule_work(&chip->ppu_work);
157}
158
159static int mv88e6xxx_phy_ppu_access_get(struct mv88e6xxx_chip *chip)
160{
161	int ret;
162
163	mutex_lock(&chip->ppu_mutex);
164
165	/* If the PHY polling unit is enabled, disable it so that
166	 * we can access the PHY registers.  If it was already
167	 * disabled, cancel the timer that is going to re-enable
168	 * it.
169	 */
170	if (!chip->ppu_disabled) {
171		ret = mv88e6xxx_phy_ppu_disable(chip);
172		if (ret < 0) {
173			mutex_unlock(&chip->ppu_mutex);
174			return ret;
175		}
176		chip->ppu_disabled = 1;
177	} else {
178		del_timer(&chip->ppu_timer);
179		ret = 0;
180	}
181
182	return ret;
183}
184
185static void mv88e6xxx_phy_ppu_access_put(struct mv88e6xxx_chip *chip)
186{
187	/* Schedule a timer to re-enable the PHY polling unit. */
188	mod_timer(&chip->ppu_timer, jiffies + msecs_to_jiffies(10));
189	mutex_unlock(&chip->ppu_mutex);
190}
191
192static void mv88e6xxx_phy_ppu_state_init(struct mv88e6xxx_chip *chip)
193{
194	mutex_init(&chip->ppu_mutex);
195	INIT_WORK(&chip->ppu_work, mv88e6xxx_phy_ppu_reenable_work);
196	timer_setup(&chip->ppu_timer, mv88e6xxx_phy_ppu_reenable_timer, 0);
197}
198
199static void mv88e6xxx_phy_ppu_state_destroy(struct mv88e6xxx_chip *chip)
200{
201	del_timer_sync(&chip->ppu_timer);
202}
203
204int mv88e6185_phy_ppu_read(struct mv88e6xxx_chip *chip, struct mii_bus *bus,
205			   int addr, int reg, u16 *val)
206{
207	int err;
208
209	err = mv88e6xxx_phy_ppu_access_get(chip);
210	if (!err) {
211		err = mv88e6xxx_read(chip, addr, reg, val);
212		mv88e6xxx_phy_ppu_access_put(chip);
213	}
214
215	return err;
216}
217
218int mv88e6185_phy_ppu_write(struct mv88e6xxx_chip *chip, struct mii_bus *bus,
219			    int addr, int reg, u16 val)
220{
221	int err;
222
223	err = mv88e6xxx_phy_ppu_access_get(chip);
224	if (!err) {
225		err = mv88e6xxx_write(chip, addr, reg, val);
226		mv88e6xxx_phy_ppu_access_put(chip);
227	}
228
229	return err;
230}
231
232void mv88e6xxx_phy_init(struct mv88e6xxx_chip *chip)
233{
234	if (chip->info->ops->ppu_enable && chip->info->ops->ppu_disable)
235		mv88e6xxx_phy_ppu_state_init(chip);
236}
237
238void mv88e6xxx_phy_destroy(struct mv88e6xxx_chip *chip)
239{
240	if (chip->info->ops->ppu_enable && chip->info->ops->ppu_disable)
241		mv88e6xxx_phy_ppu_state_destroy(chip);
242}
243
244int mv88e6xxx_phy_setup(struct mv88e6xxx_chip *chip)
245{
246	return mv88e6xxx_phy_ppu_enable(chip);
247}