xref: /openbmc/linux/drivers/net/dsa/mv88e6xxx/phy.c (revision aac28965)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Marvell 88e6xxx Ethernet switch PHY and PPU support
4  *
5  * Copyright (c) 2008 Marvell Semiconductor
6  *
7  * Copyright (c) 2017 Andrew Lunn <andrew@lunn.ch>
8  */
9 
10 #include <linux/mdio.h>
11 #include <linux/module.h>
12 
13 #include "chip.h"
14 #include "phy.h"
15 
16 int mv88e6165_phy_read(struct mv88e6xxx_chip *chip, struct mii_bus *bus,
17 		       int addr, int reg, u16 *val)
18 {
19 	return mv88e6xxx_read(chip, addr, reg, val);
20 }
21 
22 int mv88e6165_phy_write(struct mv88e6xxx_chip *chip, struct mii_bus *bus,
23 			int addr, int reg, u16 val)
24 {
25 	return mv88e6xxx_write(chip, addr, reg, val);
26 }
27 
28 int mv88e6xxx_phy_read(struct mv88e6xxx_chip *chip, int phy, int reg, u16 *val)
29 {
30 	int addr = phy; /* PHY devices addresses start at 0x0 */
31 	struct mii_bus *bus;
32 
33 	bus = mv88e6xxx_default_mdio_bus(chip);
34 	if (!bus)
35 		return -EOPNOTSUPP;
36 
37 	if (!chip->info->ops->phy_read)
38 		return -EOPNOTSUPP;
39 
40 	return chip->info->ops->phy_read(chip, bus, addr, reg, val);
41 }
42 
43 int mv88e6xxx_phy_write(struct mv88e6xxx_chip *chip, int phy, int reg, u16 val)
44 {
45 	int addr = phy; /* PHY devices addresses start at 0x0 */
46 	struct mii_bus *bus;
47 
48 	bus = mv88e6xxx_default_mdio_bus(chip);
49 	if (!bus)
50 		return -EOPNOTSUPP;
51 
52 	if (!chip->info->ops->phy_write)
53 		return -EOPNOTSUPP;
54 
55 	return chip->info->ops->phy_write(chip, bus, addr, reg, val);
56 }
57 
58 static int mv88e6xxx_phy_page_get(struct mv88e6xxx_chip *chip, int phy, u8 page)
59 {
60 	return mv88e6xxx_phy_write(chip, phy, MV88E6XXX_PHY_PAGE, page);
61 }
62 
63 static void mv88e6xxx_phy_page_put(struct mv88e6xxx_chip *chip, int phy)
64 {
65 	int err;
66 
67 	/* Restore PHY page Copper 0x0 for access via the registered
68 	 * MDIO bus
69 	 */
70 	err = mv88e6xxx_phy_write(chip, phy, MV88E6XXX_PHY_PAGE,
71 				  MV88E6XXX_PHY_PAGE_COPPER);
72 	if (unlikely(err)) {
73 		dev_err(chip->dev,
74 			"failed to restore PHY %d page Copper (%d)\n",
75 			phy, err);
76 	}
77 }
78 
79 int mv88e6xxx_phy_page_read(struct mv88e6xxx_chip *chip, int phy,
80 			    u8 page, int reg, u16 *val)
81 {
82 	int err;
83 
84 	/* There is no paging for registers 22 */
85 	if (reg == MV88E6XXX_PHY_PAGE)
86 		return -EINVAL;
87 
88 	err = mv88e6xxx_phy_page_get(chip, phy, page);
89 	if (!err) {
90 		err = mv88e6xxx_phy_read(chip, phy, reg, val);
91 		mv88e6xxx_phy_page_put(chip, phy);
92 	}
93 
94 	return err;
95 }
96 
97 int mv88e6xxx_phy_page_write(struct mv88e6xxx_chip *chip, int phy,
98 			     u8 page, int reg, u16 val)
99 {
100 	int err;
101 
102 	/* There is no paging for registers 22 */
103 	if (reg == MV88E6XXX_PHY_PAGE)
104 		return -EINVAL;
105 
106 	err = mv88e6xxx_phy_page_get(chip, phy, page);
107 	if (!err) {
108 		err = mv88e6xxx_phy_write(chip, phy, MV88E6XXX_PHY_PAGE, page);
109 		if (!err)
110 			err = mv88e6xxx_phy_write(chip, phy, reg, val);
111 
112 		mv88e6xxx_phy_page_put(chip, phy);
113 	}
114 
115 	return err;
116 }
117 
118 static int mv88e6xxx_phy_ppu_disable(struct mv88e6xxx_chip *chip)
119 {
120 	if (!chip->info->ops->ppu_disable)
121 		return 0;
122 
123 	return chip->info->ops->ppu_disable(chip);
124 }
125 
126 static int mv88e6xxx_phy_ppu_enable(struct mv88e6xxx_chip *chip)
127 {
128 	if (!chip->info->ops->ppu_enable)
129 		return 0;
130 
131 	return chip->info->ops->ppu_enable(chip);
132 }
133 
134 static void mv88e6xxx_phy_ppu_reenable_work(struct work_struct *ugly)
135 {
136 	struct mv88e6xxx_chip *chip;
137 
138 	chip = container_of(ugly, struct mv88e6xxx_chip, ppu_work);
139 
140 	mv88e6xxx_reg_lock(chip);
141 
142 	if (mutex_trylock(&chip->ppu_mutex)) {
143 		if (mv88e6xxx_phy_ppu_enable(chip) == 0)
144 			chip->ppu_disabled = 0;
145 		mutex_unlock(&chip->ppu_mutex);
146 	}
147 
148 	mv88e6xxx_reg_unlock(chip);
149 }
150 
151 static void mv88e6xxx_phy_ppu_reenable_timer(struct timer_list *t)
152 {
153 	struct mv88e6xxx_chip *chip = from_timer(chip, t, ppu_timer);
154 
155 	schedule_work(&chip->ppu_work);
156 }
157 
158 static int mv88e6xxx_phy_ppu_access_get(struct mv88e6xxx_chip *chip)
159 {
160 	int ret;
161 
162 	mutex_lock(&chip->ppu_mutex);
163 
164 	/* If the PHY polling unit is enabled, disable it so that
165 	 * we can access the PHY registers.  If it was already
166 	 * disabled, cancel the timer that is going to re-enable
167 	 * it.
168 	 */
169 	if (!chip->ppu_disabled) {
170 		ret = mv88e6xxx_phy_ppu_disable(chip);
171 		if (ret < 0) {
172 			mutex_unlock(&chip->ppu_mutex);
173 			return ret;
174 		}
175 		chip->ppu_disabled = 1;
176 	} else {
177 		del_timer(&chip->ppu_timer);
178 		ret = 0;
179 	}
180 
181 	return ret;
182 }
183 
184 static void mv88e6xxx_phy_ppu_access_put(struct mv88e6xxx_chip *chip)
185 {
186 	/* Schedule a timer to re-enable the PHY polling unit. */
187 	mod_timer(&chip->ppu_timer, jiffies + msecs_to_jiffies(10));
188 	mutex_unlock(&chip->ppu_mutex);
189 }
190 
191 static void mv88e6xxx_phy_ppu_state_init(struct mv88e6xxx_chip *chip)
192 {
193 	mutex_init(&chip->ppu_mutex);
194 	INIT_WORK(&chip->ppu_work, mv88e6xxx_phy_ppu_reenable_work);
195 	timer_setup(&chip->ppu_timer, mv88e6xxx_phy_ppu_reenable_timer, 0);
196 }
197 
198 static void mv88e6xxx_phy_ppu_state_destroy(struct mv88e6xxx_chip *chip)
199 {
200 	del_timer_sync(&chip->ppu_timer);
201 }
202 
203 int mv88e6185_phy_ppu_read(struct mv88e6xxx_chip *chip, struct mii_bus *bus,
204 			   int addr, int reg, u16 *val)
205 {
206 	int err;
207 
208 	err = mv88e6xxx_phy_ppu_access_get(chip);
209 	if (!err) {
210 		err = mv88e6xxx_read(chip, addr, reg, val);
211 		mv88e6xxx_phy_ppu_access_put(chip);
212 	}
213 
214 	return err;
215 }
216 
217 int mv88e6185_phy_ppu_write(struct mv88e6xxx_chip *chip, struct mii_bus *bus,
218 			    int addr, int reg, u16 val)
219 {
220 	int err;
221 
222 	err = mv88e6xxx_phy_ppu_access_get(chip);
223 	if (!err) {
224 		err = mv88e6xxx_write(chip, addr, reg, val);
225 		mv88e6xxx_phy_ppu_access_put(chip);
226 	}
227 
228 	return err;
229 }
230 
231 void mv88e6xxx_phy_init(struct mv88e6xxx_chip *chip)
232 {
233 	if (chip->info->ops->ppu_enable && chip->info->ops->ppu_disable)
234 		mv88e6xxx_phy_ppu_state_init(chip);
235 }
236 
237 void mv88e6xxx_phy_destroy(struct mv88e6xxx_chip *chip)
238 {
239 	if (chip->info->ops->ppu_enable && chip->info->ops->ppu_disable)
240 		mv88e6xxx_phy_ppu_state_destroy(chip);
241 }
242 
243 int mv88e6xxx_phy_setup(struct mv88e6xxx_chip *chip)
244 {
245 	return mv88e6xxx_phy_ppu_enable(chip);
246 }
247