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 .max_raw_read = 1,
90 .max_raw_write = 1,
91 },
92 {
93 .read = ksz8863_mdio_read,
94 .write = ksz8863_mdio_write,
95 .val_format_endian_default = REGMAP_ENDIAN_BIG,
96 .max_raw_read = 2,
97 .max_raw_write = 2,
98 },
99 {
100 .read = ksz8863_mdio_read,
101 .write = ksz8863_mdio_write,
102 .val_format_endian_default = REGMAP_ENDIAN_BIG,
103 .max_raw_read = 4,
104 .max_raw_write = 4,
105 }
106 };
107
108 static const struct regmap_config ksz8863_regmap_config[] = {
109 {
110 .name = "#8",
111 .reg_bits = 8,
112 .pad_bits = 24,
113 .val_bits = 8,
114 .cache_type = REGCACHE_NONE,
115 .use_single_read = 1,
116 .lock = ksz_regmap_lock,
117 .unlock = ksz_regmap_unlock,
118 },
119 {
120 .name = "#16",
121 .reg_bits = 8,
122 .pad_bits = 24,
123 .val_bits = 16,
124 .cache_type = REGCACHE_NONE,
125 .use_single_read = 1,
126 .lock = ksz_regmap_lock,
127 .unlock = ksz_regmap_unlock,
128 },
129 {
130 .name = "#32",
131 .reg_bits = 8,
132 .pad_bits = 24,
133 .val_bits = 32,
134 .cache_type = REGCACHE_NONE,
135 .use_single_read = 1,
136 .lock = ksz_regmap_lock,
137 .unlock = ksz_regmap_unlock,
138 }
139 };
140
ksz8863_smi_probe(struct mdio_device * mdiodev)141 static int ksz8863_smi_probe(struct mdio_device *mdiodev)
142 {
143 struct regmap_config rc;
144 struct ksz_device *dev;
145 struct ksz8 *ksz8;
146 int ret;
147 int i;
148
149 ksz8 = devm_kzalloc(&mdiodev->dev, sizeof(struct ksz8), GFP_KERNEL);
150 if (!ksz8)
151 return -ENOMEM;
152
153 ksz8->priv = mdiodev;
154
155 dev = ksz_switch_alloc(&mdiodev->dev, ksz8);
156 if (!dev)
157 return -ENOMEM;
158
159 for (i = 0; i < ARRAY_SIZE(ksz8863_regmap_config); i++) {
160 rc = ksz8863_regmap_config[i];
161 rc.lock_arg = &dev->regmap_mutex;
162 dev->regmap[i] = devm_regmap_init(&mdiodev->dev,
163 ®map_smi[i], dev,
164 &rc);
165 if (IS_ERR(dev->regmap[i])) {
166 ret = PTR_ERR(dev->regmap[i]);
167 dev_err(&mdiodev->dev,
168 "Failed to initialize regmap%i: %d\n",
169 ksz8863_regmap_config[i].val_bits, ret);
170 return ret;
171 }
172 }
173
174 if (mdiodev->dev.platform_data)
175 dev->pdata = mdiodev->dev.platform_data;
176
177 ret = ksz8_switch_register(dev);
178
179 /* Main DSA driver may not be started yet. */
180 if (ret)
181 return ret;
182
183 dev_set_drvdata(&mdiodev->dev, dev);
184
185 return 0;
186 }
187
ksz8863_smi_remove(struct mdio_device * mdiodev)188 static void ksz8863_smi_remove(struct mdio_device *mdiodev)
189 {
190 struct ksz_device *dev = dev_get_drvdata(&mdiodev->dev);
191
192 if (dev)
193 ksz_switch_remove(dev);
194
195 dev_set_drvdata(&mdiodev->dev, NULL);
196 }
197
ksz8863_smi_shutdown(struct mdio_device * mdiodev)198 static void ksz8863_smi_shutdown(struct mdio_device *mdiodev)
199 {
200 struct ksz_device *dev = dev_get_drvdata(&mdiodev->dev);
201
202 if (dev)
203 dsa_switch_shutdown(dev->ds);
204
205 dev_set_drvdata(&mdiodev->dev, NULL);
206 }
207
208 static const struct of_device_id ksz8863_dt_ids[] = {
209 {
210 .compatible = "microchip,ksz8863",
211 .data = &ksz_switch_chips[KSZ8830]
212 },
213 {
214 .compatible = "microchip,ksz8873",
215 .data = &ksz_switch_chips[KSZ8830]
216 },
217 { },
218 };
219 MODULE_DEVICE_TABLE(of, ksz8863_dt_ids);
220
221 static struct mdio_driver ksz8863_driver = {
222 .probe = ksz8863_smi_probe,
223 .remove = ksz8863_smi_remove,
224 .shutdown = ksz8863_smi_shutdown,
225 .mdiodrv.driver = {
226 .name = "ksz8863-switch",
227 .of_match_table = ksz8863_dt_ids,
228 },
229 };
230
231 mdio_module_driver(ksz8863_driver);
232
233 MODULE_AUTHOR("Michael Grzeschik <m.grzeschik@pengutronix.de>");
234 MODULE_DESCRIPTION("Microchip KSZ8863 SMI Switch driver");
235 MODULE_LICENSE("GPL v2");
236