1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Microchip KSZ8863 series register access through SMI
4 *
5 * Copyright (C) 2019 Pengutronix, Michael Grzeschik <kernel@pengutronix.de>
6 */
7
8 #include "ksz8.h"
9 #include "ksz_common.h"
10
11 /* Serial Management Interface (SMI) uses the following frame format:
12 *
13 * preamble|start|Read/Write| PHY | REG |TA| Data bits | Idle
14 * |frame| OP code |address |address| | |
15 * read | 32x1´s | 01 | 00 | 1xRRR | RRRRR |Z0| 00000000DDDDDDDD | Z
16 * write| 32x1´s | 01 | 00 | 0xRRR | RRRRR |10| xxxxxxxxDDDDDDDD | Z
17 *
18 */
19
20 #define SMI_KSZ88XX_READ_PHY BIT(4)
21
ksz8863_mdio_read(void * ctx,const void * reg_buf,size_t reg_len,void * val_buf,size_t val_len)22 static int ksz8863_mdio_read(void *ctx, const void *reg_buf, size_t reg_len,
23 void *val_buf, size_t val_len)
24 {
25 struct ksz_device *dev = ctx;
26 struct mdio_device *mdev;
27 u8 reg = *(u8 *)reg_buf;
28 u8 *val = val_buf;
29 struct ksz8 *ksz8;
30 int i, ret = 0;
31
32 ksz8 = dev->priv;
33 mdev = ksz8->priv;
34
35 mutex_lock_nested(&mdev->bus->mdio_lock, MDIO_MUTEX_NESTED);
36 for (i = 0; i < val_len; i++) {
37 int tmp = reg + i;
38
39 ret = __mdiobus_read(mdev->bus, ((tmp & 0xE0) >> 5) |
40 SMI_KSZ88XX_READ_PHY, tmp);
41 if (ret < 0)
42 goto out;
43
44 val[i] = ret;
45 }
46 ret = 0;
47
48 out:
49 mutex_unlock(&mdev->bus->mdio_lock);
50
51 return ret;
52 }
53
ksz8863_mdio_write(void * ctx,const void * data,size_t count)54 static int ksz8863_mdio_write(void *ctx, const void *data, size_t count)
55 {
56 struct ksz_device *dev = ctx;
57 struct mdio_device *mdev;
58 struct ksz8 *ksz8;
59 int i, ret = 0;
60 u32 reg;
61 u8 *val;
62
63 ksz8 = dev->priv;
64 mdev = ksz8->priv;
65
66 val = (u8 *)(data + 4);
67 reg = *(u32 *)data;
68
69 mutex_lock_nested(&mdev->bus->mdio_lock, MDIO_MUTEX_NESTED);
70 for (i = 0; i < (count - 4); i++) {
71 int tmp = reg + i;
72
73 ret = __mdiobus_write(mdev->bus, ((tmp & 0xE0) >> 5),
74 tmp, val[i]);
75 if (ret < 0)
76 goto out;
77 }
78
79 out:
80 mutex_unlock(&mdev->bus->mdio_lock);
81
82 return ret;
83 }
84
85 static const struct regmap_bus regmap_smi[] = {
86 {
87 .read = ksz8863_mdio_read,
88 .write = ksz8863_mdio_write,
89 },
90 {
91 .read = ksz8863_mdio_read,
92 .write = ksz8863_mdio_write,
93 .val_format_endian_default = REGMAP_ENDIAN_BIG,
94 },
95 {
96 .read = ksz8863_mdio_read,
97 .write = ksz8863_mdio_write,
98 .val_format_endian_default = REGMAP_ENDIAN_BIG,
99 }
100 };
101
102 static const struct regmap_config ksz8863_regmap_config[] = {
103 {
104 .name = "#8",
105 .reg_bits = 8,
106 .pad_bits = 24,
107 .val_bits = 8,
108 .cache_type = REGCACHE_NONE,
109 .lock = ksz_regmap_lock,
110 .unlock = ksz_regmap_unlock,
111 },
112 {
113 .name = "#16",
114 .reg_bits = 8,
115 .pad_bits = 24,
116 .val_bits = 16,
117 .cache_type = REGCACHE_NONE,
118 .lock = ksz_regmap_lock,
119 .unlock = ksz_regmap_unlock,
120 },
121 {
122 .name = "#32",
123 .reg_bits = 8,
124 .pad_bits = 24,
125 .val_bits = 32,
126 .cache_type = REGCACHE_NONE,
127 .lock = ksz_regmap_lock,
128 .unlock = ksz_regmap_unlock,
129 }
130 };
131
ksz8863_smi_probe(struct mdio_device * mdiodev)132 static int ksz8863_smi_probe(struct mdio_device *mdiodev)
133 {
134 struct regmap_config rc;
135 struct ksz_device *dev;
136 struct ksz8 *ksz8;
137 int ret;
138 int i;
139
140 ksz8 = devm_kzalloc(&mdiodev->dev, sizeof(struct ksz8), GFP_KERNEL);
141 if (!ksz8)
142 return -ENOMEM;
143
144 ksz8->priv = mdiodev;
145
146 dev = ksz_switch_alloc(&mdiodev->dev, ksz8);
147 if (!dev)
148 return -ENOMEM;
149
150 for (i = 0; i < ARRAY_SIZE(ksz8863_regmap_config); i++) {
151 rc = ksz8863_regmap_config[i];
152 rc.lock_arg = &dev->regmap_mutex;
153 dev->regmap[i] = devm_regmap_init(&mdiodev->dev,
154 ®map_smi[i], dev,
155 &rc);
156 if (IS_ERR(dev->regmap[i])) {
157 ret = PTR_ERR(dev->regmap[i]);
158 dev_err(&mdiodev->dev,
159 "Failed to initialize regmap%i: %d\n",
160 ksz8863_regmap_config[i].val_bits, ret);
161 return ret;
162 }
163 }
164
165 if (mdiodev->dev.platform_data)
166 dev->pdata = mdiodev->dev.platform_data;
167
168 ret = ksz8_switch_register(dev);
169
170 /* Main DSA driver may not be started yet. */
171 if (ret)
172 return ret;
173
174 dev_set_drvdata(&mdiodev->dev, dev);
175
176 return 0;
177 }
178
ksz8863_smi_remove(struct mdio_device * mdiodev)179 static void ksz8863_smi_remove(struct mdio_device *mdiodev)
180 {
181 struct ksz_device *dev = dev_get_drvdata(&mdiodev->dev);
182
183 if (dev)
184 ksz_switch_remove(dev);
185
186 dev_set_drvdata(&mdiodev->dev, NULL);
187 }
188
ksz8863_smi_shutdown(struct mdio_device * mdiodev)189 static void ksz8863_smi_shutdown(struct mdio_device *mdiodev)
190 {
191 struct ksz_device *dev = dev_get_drvdata(&mdiodev->dev);
192
193 if (dev)
194 dsa_switch_shutdown(dev->ds);
195
196 dev_set_drvdata(&mdiodev->dev, NULL);
197 }
198
199 static const struct of_device_id ksz8863_dt_ids[] = {
200 { .compatible = "microchip,ksz8863" },
201 { .compatible = "microchip,ksz8873" },
202 { },
203 };
204 MODULE_DEVICE_TABLE(of, ksz8863_dt_ids);
205
206 static struct mdio_driver ksz8863_driver = {
207 .probe = ksz8863_smi_probe,
208 .remove = ksz8863_smi_remove,
209 .shutdown = ksz8863_smi_shutdown,
210 .mdiodrv.driver = {
211 .name = "ksz8863-switch",
212 .of_match_table = ksz8863_dt_ids,
213 },
214 };
215
216 mdio_module_driver(ksz8863_driver);
217
218 MODULE_AUTHOR("Michael Grzeschik <m.grzeschik@pengutronix.de>");
219 MODULE_DESCRIPTION("Microchip KSZ8863 SMI Switch driver");
220 MODULE_LICENSE("GPL v2");
221