1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* |
3 | * I2C driver for Renesas Synchronization Management Unit (SMU) devices. |
4 | * |
5 | * Copyright (C) 2021 Integrated Device Technology, Inc., a Renesas Company. |
6 | */ |
7 | |
8 | #include <linux/i2c.h> |
9 | #include <linux/init.h> |
10 | #include <linux/kernel.h> |
11 | #include <linux/mfd/core.h> |
12 | #include <linux/mfd/rsmu.h> |
13 | #include <linux/module.h> |
14 | #include <linux/of.h> |
15 | #include <linux/regmap.h> |
16 | #include <linux/slab.h> |
17 | |
18 | #include "rsmu.h" |
19 | |
20 | /* |
21 | * 32-bit register address: the lower 8 bits of the register address come |
22 | * from the offset addr byte and the upper 24 bits come from the page register. |
23 | */ |
24 | #define RSMU_CM_PAGE_ADDR 0xFC |
25 | #define RSMU_CM_PAGE_MASK 0xFFFFFF00 |
26 | #define RSMU_CM_ADDRESS_MASK 0x000000FF |
27 | |
28 | /* |
29 | * 15-bit register address: the lower 7 bits of the register address come |
30 | * from the offset addr byte and the upper 8 bits come from the page register. |
31 | */ |
32 | #define RSMU_SABRE_PAGE_ADDR 0x7F |
33 | #define RSMU_SABRE_PAGE_WINDOW 128 |
34 | |
35 | static const struct regmap_range_cfg rsmu_sabre_range_cfg[] = { |
36 | { |
37 | .range_min = 0, |
38 | .range_max = 0x400, |
39 | .selector_reg = RSMU_SABRE_PAGE_ADDR, |
40 | .selector_mask = 0xFF, |
41 | .selector_shift = 0, |
42 | .window_start = 0, |
43 | .window_len = RSMU_SABRE_PAGE_WINDOW, |
44 | } |
45 | }; |
46 | |
47 | static bool rsmu_sabre_volatile_reg(struct device *dev, unsigned int reg) |
48 | { |
49 | switch (reg) { |
50 | case RSMU_SABRE_PAGE_ADDR: |
51 | return false; |
52 | default: |
53 | return true; |
54 | } |
55 | } |
56 | |
57 | static int rsmu_read_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u16 bytes) |
58 | { |
59 | struct i2c_client *client = to_i2c_client(rsmu->dev); |
60 | struct i2c_msg msg[2]; |
61 | int cnt; |
62 | |
63 | msg[0].addr = client->addr; |
64 | msg[0].flags = 0; |
65 | msg[0].len = 1; |
66 | msg[0].buf = ® |
67 | |
68 | msg[1].addr = client->addr; |
69 | msg[1].flags = I2C_M_RD; |
70 | msg[1].len = bytes; |
71 | msg[1].buf = buf; |
72 | |
73 | cnt = i2c_transfer(adap: client->adapter, msgs: msg, num: 2); |
74 | |
75 | if (cnt < 0) { |
76 | dev_err(rsmu->dev, "i2c_transfer failed at addr: %04x!" , reg); |
77 | return cnt; |
78 | } else if (cnt != 2) { |
79 | dev_err(rsmu->dev, |
80 | "i2c_transfer sent only %d of 2 messages" , cnt); |
81 | return -EIO; |
82 | } |
83 | |
84 | return 0; |
85 | } |
86 | |
87 | static int rsmu_write_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u16 bytes) |
88 | { |
89 | struct i2c_client *client = to_i2c_client(rsmu->dev); |
90 | u8 msg[RSMU_MAX_WRITE_COUNT + 1]; /* 1 Byte added for the device register */ |
91 | int cnt; |
92 | |
93 | if (bytes > RSMU_MAX_WRITE_COUNT) |
94 | return -EINVAL; |
95 | |
96 | msg[0] = reg; |
97 | memcpy(&msg[1], buf, bytes); |
98 | |
99 | cnt = i2c_master_send(client, buf: msg, count: bytes + 1); |
100 | |
101 | if (cnt < 0) { |
102 | dev_err(&client->dev, |
103 | "i2c_master_send failed at addr: %04x!" , reg); |
104 | return cnt; |
105 | } |
106 | |
107 | return 0; |
108 | } |
109 | |
110 | static int rsmu_write_page_register(struct rsmu_ddata *rsmu, u32 reg) |
111 | { |
112 | u32 page = reg & RSMU_CM_PAGE_MASK; |
113 | u8 buf[4]; |
114 | int err; |
115 | |
116 | /* Do not modify offset register for none-scsr registers */ |
117 | if (reg < RSMU_CM_SCSR_BASE) |
118 | return 0; |
119 | |
120 | /* Simply return if we are on the same page */ |
121 | if (rsmu->page == page) |
122 | return 0; |
123 | |
124 | buf[0] = 0x0; |
125 | buf[1] = (u8)((page >> 8) & 0xFF); |
126 | buf[2] = (u8)((page >> 16) & 0xFF); |
127 | buf[3] = (u8)((page >> 24) & 0xFF); |
128 | |
129 | err = rsmu_write_device(rsmu, RSMU_CM_PAGE_ADDR, buf, bytes: sizeof(buf)); |
130 | if (err) |
131 | dev_err(rsmu->dev, "Failed to set page offset 0x%x\n" , page); |
132 | else |
133 | /* Remember the last page */ |
134 | rsmu->page = page; |
135 | |
136 | return err; |
137 | } |
138 | |
139 | static int rsmu_reg_read(void *context, unsigned int reg, unsigned int *val) |
140 | { |
141 | struct rsmu_ddata *rsmu = i2c_get_clientdata(client: (struct i2c_client *)context); |
142 | u8 addr = (u8)(reg & RSMU_CM_ADDRESS_MASK); |
143 | int err; |
144 | |
145 | err = rsmu_write_page_register(rsmu, reg); |
146 | if (err) |
147 | return err; |
148 | |
149 | err = rsmu_read_device(rsmu, reg: addr, buf: (u8 *)val, bytes: 1); |
150 | if (err) |
151 | dev_err(rsmu->dev, "Failed to read offset address 0x%x\n" , addr); |
152 | |
153 | return err; |
154 | } |
155 | |
156 | static int rsmu_reg_write(void *context, unsigned int reg, unsigned int val) |
157 | { |
158 | struct rsmu_ddata *rsmu = i2c_get_clientdata(client: (struct i2c_client *)context); |
159 | u8 addr = (u8)(reg & RSMU_CM_ADDRESS_MASK); |
160 | u8 data = (u8)val; |
161 | int err; |
162 | |
163 | err = rsmu_write_page_register(rsmu, reg); |
164 | if (err) |
165 | return err; |
166 | |
167 | err = rsmu_write_device(rsmu, reg: addr, buf: &data, bytes: 1); |
168 | if (err) |
169 | dev_err(rsmu->dev, |
170 | "Failed to write offset address 0x%x\n" , addr); |
171 | |
172 | return err; |
173 | } |
174 | |
175 | static const struct regmap_config rsmu_cm_regmap_config = { |
176 | .reg_bits = 32, |
177 | .val_bits = 8, |
178 | .max_register = 0x20120000, |
179 | .reg_read = rsmu_reg_read, |
180 | .reg_write = rsmu_reg_write, |
181 | .cache_type = REGCACHE_NONE, |
182 | }; |
183 | |
184 | static const struct regmap_config rsmu_sabre_regmap_config = { |
185 | .reg_bits = 8, |
186 | .val_bits = 8, |
187 | .max_register = 0x400, |
188 | .ranges = rsmu_sabre_range_cfg, |
189 | .num_ranges = ARRAY_SIZE(rsmu_sabre_range_cfg), |
190 | .volatile_reg = rsmu_sabre_volatile_reg, |
191 | .cache_type = REGCACHE_MAPLE, |
192 | .can_multi_write = true, |
193 | }; |
194 | |
195 | static const struct regmap_config rsmu_sl_regmap_config = { |
196 | .reg_bits = 16, |
197 | .val_bits = 8, |
198 | .reg_format_endian = REGMAP_ENDIAN_BIG, |
199 | .max_register = 0x340, |
200 | .cache_type = REGCACHE_NONE, |
201 | .can_multi_write = true, |
202 | }; |
203 | |
204 | static int rsmu_i2c_probe(struct i2c_client *client) |
205 | { |
206 | const struct i2c_device_id *id = i2c_client_get_device_id(client); |
207 | const struct regmap_config *cfg; |
208 | struct rsmu_ddata *rsmu; |
209 | int ret; |
210 | |
211 | rsmu = devm_kzalloc(dev: &client->dev, size: sizeof(*rsmu), GFP_KERNEL); |
212 | if (!rsmu) |
213 | return -ENOMEM; |
214 | |
215 | i2c_set_clientdata(client, data: rsmu); |
216 | |
217 | rsmu->dev = &client->dev; |
218 | rsmu->type = (enum rsmu_type)id->driver_data; |
219 | |
220 | switch (rsmu->type) { |
221 | case RSMU_CM: |
222 | cfg = &rsmu_cm_regmap_config; |
223 | break; |
224 | case RSMU_SABRE: |
225 | cfg = &rsmu_sabre_regmap_config; |
226 | break; |
227 | case RSMU_SL: |
228 | cfg = &rsmu_sl_regmap_config; |
229 | break; |
230 | default: |
231 | dev_err(rsmu->dev, "Unsupported RSMU device type: %d\n" , rsmu->type); |
232 | return -ENODEV; |
233 | } |
234 | |
235 | if (rsmu->type == RSMU_CM) |
236 | rsmu->regmap = devm_regmap_init(&client->dev, NULL, client, cfg); |
237 | else |
238 | rsmu->regmap = devm_regmap_init_i2c(client, cfg); |
239 | if (IS_ERR(ptr: rsmu->regmap)) { |
240 | ret = PTR_ERR(ptr: rsmu->regmap); |
241 | dev_err(rsmu->dev, "Failed to allocate register map: %d\n" , ret); |
242 | return ret; |
243 | } |
244 | |
245 | return rsmu_core_init(rsmu); |
246 | } |
247 | |
248 | static void rsmu_i2c_remove(struct i2c_client *client) |
249 | { |
250 | struct rsmu_ddata *rsmu = i2c_get_clientdata(client); |
251 | |
252 | rsmu_core_exit(rsmu); |
253 | } |
254 | |
255 | static const struct i2c_device_id rsmu_i2c_id[] = { |
256 | { "8a34000" , RSMU_CM }, |
257 | { "8a34001" , RSMU_CM }, |
258 | { "82p33810" , RSMU_SABRE }, |
259 | { "82p33811" , RSMU_SABRE }, |
260 | { "8v19n850" , RSMU_SL }, |
261 | { "8v19n851" , RSMU_SL }, |
262 | {} |
263 | }; |
264 | MODULE_DEVICE_TABLE(i2c, rsmu_i2c_id); |
265 | |
266 | static const struct of_device_id rsmu_i2c_of_match[] = { |
267 | { .compatible = "idt,8a34000" , .data = (void *)RSMU_CM }, |
268 | { .compatible = "idt,8a34001" , .data = (void *)RSMU_CM }, |
269 | { .compatible = "idt,82p33810" , .data = (void *)RSMU_SABRE }, |
270 | { .compatible = "idt,82p33811" , .data = (void *)RSMU_SABRE }, |
271 | { .compatible = "idt,8v19n850" , .data = (void *)RSMU_SL }, |
272 | { .compatible = "idt,8v19n851" , .data = (void *)RSMU_SL }, |
273 | {} |
274 | }; |
275 | MODULE_DEVICE_TABLE(of, rsmu_i2c_of_match); |
276 | |
277 | static struct i2c_driver rsmu_i2c_driver = { |
278 | .driver = { |
279 | .name = "rsmu-i2c" , |
280 | .of_match_table = rsmu_i2c_of_match, |
281 | }, |
282 | .probe = rsmu_i2c_probe, |
283 | .remove = rsmu_i2c_remove, |
284 | .id_table = rsmu_i2c_id, |
285 | }; |
286 | |
287 | static int __init rsmu_i2c_init(void) |
288 | { |
289 | return i2c_add_driver(&rsmu_i2c_driver); |
290 | } |
291 | subsys_initcall(rsmu_i2c_init); |
292 | |
293 | static void __exit rsmu_i2c_exit(void) |
294 | { |
295 | i2c_del_driver(driver: &rsmu_i2c_driver); |
296 | } |
297 | module_exit(rsmu_i2c_exit); |
298 | |
299 | MODULE_DESCRIPTION("Renesas SMU I2C driver" ); |
300 | MODULE_LICENSE("GPL" ); |
301 | |