1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Lochnagar I2C bus interface
4 *
5 * Copyright (c) 2012-2018 Cirrus Logic, Inc. and
6 * Cirrus Logic International Semiconductor Ltd.
7 *
8 * Author: Charles Keepax <ckeepax@opensource.cirrus.com>
9 */
10
11 #include <linux/delay.h>
12 #include <linux/device.h>
13 #include <linux/err.h>
14 #include <linux/gpio/consumer.h>
15 #include <linux/i2c.h>
16 #include <linux/lockdep.h>
17 #include <linux/mfd/core.h>
18 #include <linux/mutex.h>
19 #include <linux/of.h>
20 #include <linux/of_platform.h>
21 #include <linux/regmap.h>
22
23 #include <linux/mfd/lochnagar.h>
24 #include <linux/mfd/lochnagar1_regs.h>
25 #include <linux/mfd/lochnagar2_regs.h>
26
27 #define LOCHNAGAR_BOOT_RETRIES 10
28 #define LOCHNAGAR_BOOT_DELAY_MS 350
29
30 #define LOCHNAGAR_CONFIG_POLL_US 10000
31
lochnagar1_readable_register(struct device * dev,unsigned int reg)32 static bool lochnagar1_readable_register(struct device *dev, unsigned int reg)
33 {
34 switch (reg) {
35 case LOCHNAGAR_SOFTWARE_RESET:
36 case LOCHNAGAR_FIRMWARE_ID1...LOCHNAGAR_FIRMWARE_ID2:
37 case LOCHNAGAR1_CDC_AIF1_SEL...LOCHNAGAR1_CDC_AIF3_SEL:
38 case LOCHNAGAR1_CDC_MCLK1_SEL...LOCHNAGAR1_CDC_MCLK2_SEL:
39 case LOCHNAGAR1_CDC_AIF_CTRL1...LOCHNAGAR1_CDC_AIF_CTRL2:
40 case LOCHNAGAR1_EXT_AIF_CTRL:
41 case LOCHNAGAR1_DSP_AIF1_SEL...LOCHNAGAR1_DSP_AIF2_SEL:
42 case LOCHNAGAR1_DSP_CLKIN_SEL:
43 case LOCHNAGAR1_DSP_AIF:
44 case LOCHNAGAR1_GF_AIF1...LOCHNAGAR1_GF_AIF2:
45 case LOCHNAGAR1_PSIA_AIF:
46 case LOCHNAGAR1_PSIA1_SEL...LOCHNAGAR1_PSIA2_SEL:
47 case LOCHNAGAR1_SPDIF_AIF_SEL:
48 case LOCHNAGAR1_GF_AIF3_SEL...LOCHNAGAR1_GF_AIF4_SEL:
49 case LOCHNAGAR1_GF_CLKOUT1_SEL:
50 case LOCHNAGAR1_GF_AIF1_SEL...LOCHNAGAR1_GF_AIF2_SEL:
51 case LOCHNAGAR1_GF_GPIO2...LOCHNAGAR1_GF_GPIO7:
52 case LOCHNAGAR1_RST:
53 case LOCHNAGAR1_LED1...LOCHNAGAR1_LED2:
54 case LOCHNAGAR1_I2C_CTRL:
55 return true;
56 default:
57 return false;
58 }
59 }
60
61 static const struct regmap_config lochnagar1_i2c_regmap = {
62 .reg_bits = 8,
63 .val_bits = 8,
64 .reg_format_endian = REGMAP_ENDIAN_BIG,
65 .val_format_endian = REGMAP_ENDIAN_BIG,
66
67 .max_register = 0x50,
68 .readable_reg = lochnagar1_readable_register,
69
70 .use_single_read = true,
71 .use_single_write = true,
72
73 .cache_type = REGCACHE_RBTREE,
74 };
75
76 static const struct reg_sequence lochnagar1_patch[] = {
77 { 0x40, 0x0083 },
78 { 0x47, 0x0018 },
79 { 0x50, 0x0000 },
80 };
81
lochnagar2_readable_register(struct device * dev,unsigned int reg)82 static bool lochnagar2_readable_register(struct device *dev, unsigned int reg)
83 {
84 switch (reg) {
85 case LOCHNAGAR_SOFTWARE_RESET:
86 case LOCHNAGAR_FIRMWARE_ID1...LOCHNAGAR_FIRMWARE_ID2:
87 case LOCHNAGAR2_CDC_AIF1_CTRL...LOCHNAGAR2_CDC_AIF3_CTRL:
88 case LOCHNAGAR2_DSP_AIF1_CTRL...LOCHNAGAR2_DSP_AIF2_CTRL:
89 case LOCHNAGAR2_PSIA1_CTRL...LOCHNAGAR2_PSIA2_CTRL:
90 case LOCHNAGAR2_GF_AIF3_CTRL...LOCHNAGAR2_GF_AIF4_CTRL:
91 case LOCHNAGAR2_GF_AIF1_CTRL...LOCHNAGAR2_GF_AIF2_CTRL:
92 case LOCHNAGAR2_SPDIF_AIF_CTRL:
93 case LOCHNAGAR2_USB_AIF1_CTRL...LOCHNAGAR2_USB_AIF2_CTRL:
94 case LOCHNAGAR2_ADAT_AIF_CTRL:
95 case LOCHNAGAR2_CDC_MCLK1_CTRL...LOCHNAGAR2_CDC_MCLK2_CTRL:
96 case LOCHNAGAR2_DSP_CLKIN_CTRL:
97 case LOCHNAGAR2_PSIA1_MCLK_CTRL...LOCHNAGAR2_PSIA2_MCLK_CTRL:
98 case LOCHNAGAR2_SPDIF_MCLK_CTRL:
99 case LOCHNAGAR2_GF_CLKOUT1_CTRL...LOCHNAGAR2_GF_CLKOUT2_CTRL:
100 case LOCHNAGAR2_ADAT_MCLK_CTRL:
101 case LOCHNAGAR2_SOUNDCARD_MCLK_CTRL:
102 case LOCHNAGAR2_GPIO_FPGA_GPIO1...LOCHNAGAR2_GPIO_FPGA_GPIO6:
103 case LOCHNAGAR2_GPIO_CDC_GPIO1...LOCHNAGAR2_GPIO_CDC_GPIO8:
104 case LOCHNAGAR2_GPIO_DSP_GPIO1...LOCHNAGAR2_GPIO_DSP_GPIO6:
105 case LOCHNAGAR2_GPIO_GF_GPIO2...LOCHNAGAR2_GPIO_GF_GPIO7:
106 case LOCHNAGAR2_GPIO_CDC_AIF1_BCLK...LOCHNAGAR2_GPIO_CDC_AIF3_TXDAT:
107 case LOCHNAGAR2_GPIO_DSP_AIF1_BCLK...LOCHNAGAR2_GPIO_DSP_AIF2_TXDAT:
108 case LOCHNAGAR2_GPIO_PSIA1_BCLK...LOCHNAGAR2_GPIO_PSIA2_TXDAT:
109 case LOCHNAGAR2_GPIO_GF_AIF3_BCLK...LOCHNAGAR2_GPIO_GF_AIF4_TXDAT:
110 case LOCHNAGAR2_GPIO_GF_AIF1_BCLK...LOCHNAGAR2_GPIO_GF_AIF2_TXDAT:
111 case LOCHNAGAR2_GPIO_DSP_UART1_RX...LOCHNAGAR2_GPIO_DSP_UART2_TX:
112 case LOCHNAGAR2_GPIO_GF_UART2_RX...LOCHNAGAR2_GPIO_GF_UART2_TX:
113 case LOCHNAGAR2_GPIO_USB_UART_RX:
114 case LOCHNAGAR2_GPIO_CDC_PDMCLK1...LOCHNAGAR2_GPIO_CDC_PDMDAT2:
115 case LOCHNAGAR2_GPIO_CDC_DMICCLK1...LOCHNAGAR2_GPIO_CDC_DMICDAT4:
116 case LOCHNAGAR2_GPIO_DSP_DMICCLK1...LOCHNAGAR2_GPIO_DSP_DMICDAT2:
117 case LOCHNAGAR2_GPIO_I2C2_SCL...LOCHNAGAR2_GPIO_I2C4_SDA:
118 case LOCHNAGAR2_GPIO_DSP_STANDBY:
119 case LOCHNAGAR2_GPIO_CDC_MCLK1...LOCHNAGAR2_GPIO_CDC_MCLK2:
120 case LOCHNAGAR2_GPIO_DSP_CLKIN:
121 case LOCHNAGAR2_GPIO_PSIA1_MCLK...LOCHNAGAR2_GPIO_PSIA2_MCLK:
122 case LOCHNAGAR2_GPIO_GF_GPIO1...LOCHNAGAR2_GPIO_GF_GPIO5:
123 case LOCHNAGAR2_GPIO_DSP_GPIO20:
124 case LOCHNAGAR2_GPIO_CHANNEL1...LOCHNAGAR2_GPIO_CHANNEL16:
125 case LOCHNAGAR2_MINICARD_RESETS:
126 case LOCHNAGAR2_ANALOGUE_PATH_CTRL1...LOCHNAGAR2_ANALOGUE_PATH_CTRL2:
127 case LOCHNAGAR2_COMMS_CTRL4:
128 case LOCHNAGAR2_SPDIF_CTRL:
129 case LOCHNAGAR2_IMON_CTRL1...LOCHNAGAR2_IMON_CTRL4:
130 case LOCHNAGAR2_IMON_DATA1...LOCHNAGAR2_IMON_DATA2:
131 case LOCHNAGAR2_POWER_CTRL:
132 case LOCHNAGAR2_MICVDD_CTRL1:
133 case LOCHNAGAR2_MICVDD_CTRL2:
134 case LOCHNAGAR2_VDDCORE_CDC_CTRL1:
135 case LOCHNAGAR2_VDDCORE_CDC_CTRL2:
136 case LOCHNAGAR2_SOUNDCARD_AIF_CTRL:
137 return true;
138 default:
139 return false;
140 }
141 }
142
lochnagar2_volatile_register(struct device * dev,unsigned int reg)143 static bool lochnagar2_volatile_register(struct device *dev, unsigned int reg)
144 {
145 switch (reg) {
146 case LOCHNAGAR2_GPIO_CHANNEL1...LOCHNAGAR2_GPIO_CHANNEL16:
147 case LOCHNAGAR2_ANALOGUE_PATH_CTRL1:
148 case LOCHNAGAR2_IMON_CTRL3...LOCHNAGAR2_IMON_CTRL4:
149 case LOCHNAGAR2_IMON_DATA1...LOCHNAGAR2_IMON_DATA2:
150 return true;
151 default:
152 return false;
153 }
154 }
155
156 static const struct regmap_config lochnagar2_i2c_regmap = {
157 .reg_bits = 16,
158 .val_bits = 16,
159 .reg_format_endian = REGMAP_ENDIAN_BIG,
160 .val_format_endian = REGMAP_ENDIAN_BIG,
161
162 .max_register = 0x1F1F,
163 .readable_reg = lochnagar2_readable_register,
164 .volatile_reg = lochnagar2_volatile_register,
165
166 .cache_type = REGCACHE_RBTREE,
167 };
168
169 static const struct reg_sequence lochnagar2_patch[] = {
170 { 0x00EE, 0x0000 },
171 };
172
173 struct lochnagar_config {
174 int id;
175 const char * const name;
176 enum lochnagar_type type;
177 const struct regmap_config *regmap;
178 const struct reg_sequence *patch;
179 int npatch;
180 };
181
182 static struct lochnagar_config lochnagar_configs[] = {
183 {
184 .id = 0x50,
185 .name = "lochnagar1",
186 .type = LOCHNAGAR1,
187 .regmap = &lochnagar1_i2c_regmap,
188 .patch = lochnagar1_patch,
189 .npatch = ARRAY_SIZE(lochnagar1_patch),
190 },
191 {
192 .id = 0xCB58,
193 .name = "lochnagar2",
194 .type = LOCHNAGAR2,
195 .regmap = &lochnagar2_i2c_regmap,
196 .patch = lochnagar2_patch,
197 .npatch = ARRAY_SIZE(lochnagar2_patch),
198 },
199 };
200
201 static const struct of_device_id lochnagar_of_match[] = {
202 { .compatible = "cirrus,lochnagar1", .data = &lochnagar_configs[0] },
203 { .compatible = "cirrus,lochnagar2", .data = &lochnagar_configs[1] },
204 {},
205 };
206
lochnagar_wait_for_boot(struct regmap * regmap,unsigned int * id)207 static int lochnagar_wait_for_boot(struct regmap *regmap, unsigned int *id)
208 {
209 int i, ret;
210
211 for (i = 0; i < LOCHNAGAR_BOOT_RETRIES; ++i) {
212 msleep(LOCHNAGAR_BOOT_DELAY_MS);
213
214 /* The reset register will return the device ID when read */
215 ret = regmap_read(regmap, LOCHNAGAR_SOFTWARE_RESET, id);
216 if (!ret)
217 return ret;
218 }
219
220 return -ETIMEDOUT;
221 }
222
223 /**
224 * lochnagar_update_config - Synchronise the boards analogue configuration to
225 * the hardware.
226 *
227 * @lochnagar: A pointer to the primary core data structure.
228 *
229 * Return: Zero on success or an appropriate negative error code on failure.
230 */
lochnagar_update_config(struct lochnagar * lochnagar)231 int lochnagar_update_config(struct lochnagar *lochnagar)
232 {
233 struct regmap *regmap = lochnagar->regmap;
234 unsigned int done = LOCHNAGAR2_ANALOGUE_PATH_UPDATE_STS_MASK;
235 int timeout_ms = LOCHNAGAR_BOOT_DELAY_MS * LOCHNAGAR_BOOT_RETRIES;
236 unsigned int val = 0;
237 int ret;
238
239 lockdep_assert_held(&lochnagar->analogue_config_lock);
240
241 if (lochnagar->type != LOCHNAGAR2)
242 return 0;
243
244 /*
245 * Toggle the ANALOGUE_PATH_UPDATE bit and wait for the device to
246 * acknowledge that any outstanding changes to the analogue
247 * configuration have been applied.
248 */
249 ret = regmap_write(regmap, LOCHNAGAR2_ANALOGUE_PATH_CTRL1, 0);
250 if (ret < 0)
251 return ret;
252
253 ret = regmap_write(regmap, LOCHNAGAR2_ANALOGUE_PATH_CTRL1,
254 LOCHNAGAR2_ANALOGUE_PATH_UPDATE_MASK);
255 if (ret < 0)
256 return ret;
257
258 ret = regmap_read_poll_timeout(regmap,
259 LOCHNAGAR2_ANALOGUE_PATH_CTRL1, val,
260 (val & done), LOCHNAGAR_CONFIG_POLL_US,
261 timeout_ms * 1000);
262 if (ret < 0)
263 return ret;
264
265 return 0;
266 }
267 EXPORT_SYMBOL_GPL(lochnagar_update_config);
268
lochnagar_i2c_probe(struct i2c_client * i2c)269 static int lochnagar_i2c_probe(struct i2c_client *i2c)
270 {
271 struct device *dev = &i2c->dev;
272 const struct lochnagar_config *config = NULL;
273 const struct of_device_id *of_id;
274 struct lochnagar *lochnagar;
275 struct gpio_desc *reset, *present;
276 unsigned int val;
277 unsigned int firmwareid;
278 unsigned int devid, rev;
279 int ret;
280
281 lochnagar = devm_kzalloc(dev, sizeof(*lochnagar), GFP_KERNEL);
282 if (!lochnagar)
283 return -ENOMEM;
284
285 of_id = of_match_device(lochnagar_of_match, dev);
286 if (!of_id)
287 return -EINVAL;
288
289 config = of_id->data;
290
291 lochnagar->dev = dev;
292 mutex_init(&lochnagar->analogue_config_lock);
293
294 dev_set_drvdata(dev, lochnagar);
295
296 reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
297 if (IS_ERR(reset)) {
298 ret = PTR_ERR(reset);
299 dev_err(dev, "Failed to get reset GPIO: %d\n", ret);
300 return ret;
301 }
302
303 present = devm_gpiod_get_optional(dev, "present", GPIOD_OUT_HIGH);
304 if (IS_ERR(present)) {
305 ret = PTR_ERR(present);
306 dev_err(dev, "Failed to get present GPIO: %d\n", ret);
307 return ret;
308 }
309
310 /* Leave the Lochnagar in reset for a reasonable amount of time */
311 msleep(20);
312
313 /* Bring Lochnagar out of reset */
314 gpiod_set_value_cansleep(reset, 1);
315
316 /* Identify Lochnagar */
317 lochnagar->type = config->type;
318
319 lochnagar->regmap = devm_regmap_init_i2c(i2c, config->regmap);
320 if (IS_ERR(lochnagar->regmap)) {
321 ret = PTR_ERR(lochnagar->regmap);
322 dev_err(dev, "Failed to allocate register map: %d\n", ret);
323 return ret;
324 }
325
326 /* Wait for Lochnagar to boot */
327 ret = lochnagar_wait_for_boot(lochnagar->regmap, &val);
328 if (ret < 0) {
329 dev_err(dev, "Failed to read device ID: %d\n", ret);
330 return ret;
331 }
332
333 devid = val & LOCHNAGAR_DEVICE_ID_MASK;
334 rev = val & LOCHNAGAR_REV_ID_MASK;
335
336 if (devid != config->id) {
337 dev_err(dev,
338 "ID does not match %s (expected 0x%x got 0x%x)\n",
339 config->name, config->id, devid);
340 return -ENODEV;
341 }
342
343 /* Identify firmware */
344 ret = regmap_read(lochnagar->regmap, LOCHNAGAR_FIRMWARE_ID1, &val);
345 if (ret < 0) {
346 dev_err(dev, "Failed to read firmware id 1: %d\n", ret);
347 return ret;
348 }
349
350 firmwareid = val;
351
352 ret = regmap_read(lochnagar->regmap, LOCHNAGAR_FIRMWARE_ID2, &val);
353 if (ret < 0) {
354 dev_err(dev, "Failed to read firmware id 2: %d\n", ret);
355 return ret;
356 }
357
358 firmwareid |= (val << config->regmap->val_bits);
359
360 dev_info(dev, "Found %s (0x%x) revision %u firmware 0x%.6x\n",
361 config->name, devid, rev + 1, firmwareid);
362
363 ret = regmap_register_patch(lochnagar->regmap, config->patch,
364 config->npatch);
365 if (ret < 0) {
366 dev_err(dev, "Failed to register patch: %d\n", ret);
367 return ret;
368 }
369
370 ret = devm_of_platform_populate(dev);
371 if (ret < 0) {
372 dev_err(dev, "Failed to populate child nodes: %d\n", ret);
373 return ret;
374 }
375
376 return ret;
377 }
378
379 static struct i2c_driver lochnagar_i2c_driver = {
380 .driver = {
381 .name = "lochnagar",
382 .of_match_table = lochnagar_of_match,
383 .suppress_bind_attrs = true,
384 },
385 .probe = lochnagar_i2c_probe,
386 };
387
lochnagar_i2c_init(void)388 static int __init lochnagar_i2c_init(void)
389 {
390 int ret;
391
392 ret = i2c_add_driver(&lochnagar_i2c_driver);
393 if (ret)
394 pr_err("Failed to register Lochnagar driver: %d\n", ret);
395
396 return ret;
397 }
398 subsys_initcall(lochnagar_i2c_init);
399