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_platform.h>
20 #include <linux/regmap.h>
21
22 #include <linux/mfd/lochnagar.h>
23 #include <linux/mfd/lochnagar1_regs.h>
24 #include <linux/mfd/lochnagar2_regs.h>
25
26 #define LOCHNAGAR_BOOT_RETRIES 10
27 #define LOCHNAGAR_BOOT_DELAY_MS 350
28
29 #define LOCHNAGAR_CONFIG_POLL_US 10000
30
lochnagar1_readable_register(struct device * dev,unsigned int reg)31 static bool lochnagar1_readable_register(struct device *dev, unsigned int reg)
32 {
33 switch (reg) {
34 case LOCHNAGAR_SOFTWARE_RESET:
35 case LOCHNAGAR_FIRMWARE_ID1...LOCHNAGAR_FIRMWARE_ID2:
36 case LOCHNAGAR1_CDC_AIF1_SEL...LOCHNAGAR1_CDC_AIF3_SEL:
37 case LOCHNAGAR1_CDC_MCLK1_SEL...LOCHNAGAR1_CDC_MCLK2_SEL:
38 case LOCHNAGAR1_CDC_AIF_CTRL1...LOCHNAGAR1_CDC_AIF_CTRL2:
39 case LOCHNAGAR1_EXT_AIF_CTRL:
40 case LOCHNAGAR1_DSP_AIF1_SEL...LOCHNAGAR1_DSP_AIF2_SEL:
41 case LOCHNAGAR1_DSP_CLKIN_SEL:
42 case LOCHNAGAR1_DSP_AIF:
43 case LOCHNAGAR1_GF_AIF1...LOCHNAGAR1_GF_AIF2:
44 case LOCHNAGAR1_PSIA_AIF:
45 case LOCHNAGAR1_PSIA1_SEL...LOCHNAGAR1_PSIA2_SEL:
46 case LOCHNAGAR1_SPDIF_AIF_SEL:
47 case LOCHNAGAR1_GF_AIF3_SEL...LOCHNAGAR1_GF_AIF4_SEL:
48 case LOCHNAGAR1_GF_CLKOUT1_SEL:
49 case LOCHNAGAR1_GF_AIF1_SEL...LOCHNAGAR1_GF_AIF2_SEL:
50 case LOCHNAGAR1_GF_GPIO2...LOCHNAGAR1_GF_GPIO7:
51 case LOCHNAGAR1_RST:
52 case LOCHNAGAR1_LED1...LOCHNAGAR1_LED2:
53 case LOCHNAGAR1_I2C_CTRL:
54 return true;
55 default:
56 return false;
57 }
58 }
59
60 static const struct regmap_config lochnagar1_i2c_regmap = {
61 .reg_bits = 8,
62 .val_bits = 8,
63 .reg_format_endian = REGMAP_ENDIAN_BIG,
64 .val_format_endian = REGMAP_ENDIAN_BIG,
65
66 .max_register = 0x50,
67 .readable_reg = lochnagar1_readable_register,
68
69 .use_single_read = true,
70 .use_single_write = true,
71
72 .cache_type = REGCACHE_MAPLE,
73 };
74
75 static const struct reg_sequence lochnagar1_patch[] = {
76 { 0x40, 0x0083 },
77 { 0x47, 0x0018 },
78 { 0x50, 0x0000 },
79 };
80
lochnagar2_readable_register(struct device * dev,unsigned int reg)81 static bool lochnagar2_readable_register(struct device *dev, unsigned int reg)
82 {
83 switch (reg) {
84 case LOCHNAGAR_SOFTWARE_RESET:
85 case LOCHNAGAR_FIRMWARE_ID1...LOCHNAGAR_FIRMWARE_ID2:
86 case LOCHNAGAR2_CDC_AIF1_CTRL...LOCHNAGAR2_CDC_AIF3_CTRL:
87 case LOCHNAGAR2_DSP_AIF1_CTRL...LOCHNAGAR2_DSP_AIF2_CTRL:
88 case LOCHNAGAR2_PSIA1_CTRL...LOCHNAGAR2_PSIA2_CTRL:
89 case LOCHNAGAR2_GF_AIF3_CTRL...LOCHNAGAR2_GF_AIF4_CTRL:
90 case LOCHNAGAR2_GF_AIF1_CTRL...LOCHNAGAR2_GF_AIF2_CTRL:
91 case LOCHNAGAR2_SPDIF_AIF_CTRL:
92 case LOCHNAGAR2_USB_AIF1_CTRL...LOCHNAGAR2_USB_AIF2_CTRL:
93 case LOCHNAGAR2_ADAT_AIF_CTRL:
94 case LOCHNAGAR2_CDC_MCLK1_CTRL...LOCHNAGAR2_CDC_MCLK2_CTRL:
95 case LOCHNAGAR2_DSP_CLKIN_CTRL:
96 case LOCHNAGAR2_PSIA1_MCLK_CTRL...LOCHNAGAR2_PSIA2_MCLK_CTRL:
97 case LOCHNAGAR2_SPDIF_MCLK_CTRL:
98 case LOCHNAGAR2_GF_CLKOUT1_CTRL...LOCHNAGAR2_GF_CLKOUT2_CTRL:
99 case LOCHNAGAR2_ADAT_MCLK_CTRL:
100 case LOCHNAGAR2_SOUNDCARD_MCLK_CTRL:
101 case LOCHNAGAR2_GPIO_FPGA_GPIO1...LOCHNAGAR2_GPIO_FPGA_GPIO6:
102 case LOCHNAGAR2_GPIO_CDC_GPIO1...LOCHNAGAR2_GPIO_CDC_GPIO8:
103 case LOCHNAGAR2_GPIO_DSP_GPIO1...LOCHNAGAR2_GPIO_DSP_GPIO6:
104 case LOCHNAGAR2_GPIO_GF_GPIO2...LOCHNAGAR2_GPIO_GF_GPIO7:
105 case LOCHNAGAR2_GPIO_CDC_AIF1_BCLK...LOCHNAGAR2_GPIO_CDC_AIF3_TXDAT:
106 case LOCHNAGAR2_GPIO_DSP_AIF1_BCLK...LOCHNAGAR2_GPIO_DSP_AIF2_TXDAT:
107 case LOCHNAGAR2_GPIO_PSIA1_BCLK...LOCHNAGAR2_GPIO_PSIA2_TXDAT:
108 case LOCHNAGAR2_GPIO_GF_AIF3_BCLK...LOCHNAGAR2_GPIO_GF_AIF4_TXDAT:
109 case LOCHNAGAR2_GPIO_GF_AIF1_BCLK...LOCHNAGAR2_GPIO_GF_AIF2_TXDAT:
110 case LOCHNAGAR2_GPIO_DSP_UART1_RX...LOCHNAGAR2_GPIO_DSP_UART2_TX:
111 case LOCHNAGAR2_GPIO_GF_UART2_RX...LOCHNAGAR2_GPIO_GF_UART2_TX:
112 case LOCHNAGAR2_GPIO_USB_UART_RX:
113 case LOCHNAGAR2_GPIO_CDC_PDMCLK1...LOCHNAGAR2_GPIO_CDC_PDMDAT2:
114 case LOCHNAGAR2_GPIO_CDC_DMICCLK1...LOCHNAGAR2_GPIO_CDC_DMICDAT4:
115 case LOCHNAGAR2_GPIO_DSP_DMICCLK1...LOCHNAGAR2_GPIO_DSP_DMICDAT2:
116 case LOCHNAGAR2_GPIO_I2C2_SCL...LOCHNAGAR2_GPIO_I2C4_SDA:
117 case LOCHNAGAR2_GPIO_DSP_STANDBY:
118 case LOCHNAGAR2_GPIO_CDC_MCLK1...LOCHNAGAR2_GPIO_CDC_MCLK2:
119 case LOCHNAGAR2_GPIO_DSP_CLKIN:
120 case LOCHNAGAR2_GPIO_PSIA1_MCLK...LOCHNAGAR2_GPIO_PSIA2_MCLK:
121 case LOCHNAGAR2_GPIO_GF_GPIO1...LOCHNAGAR2_GPIO_GF_GPIO5:
122 case LOCHNAGAR2_GPIO_DSP_GPIO20:
123 case LOCHNAGAR2_GPIO_CHANNEL1...LOCHNAGAR2_GPIO_CHANNEL16:
124 case LOCHNAGAR2_MINICARD_RESETS:
125 case LOCHNAGAR2_ANALOGUE_PATH_CTRL1...LOCHNAGAR2_ANALOGUE_PATH_CTRL2:
126 case LOCHNAGAR2_COMMS_CTRL4:
127 case LOCHNAGAR2_SPDIF_CTRL:
128 case LOCHNAGAR2_IMON_CTRL1...LOCHNAGAR2_IMON_CTRL4:
129 case LOCHNAGAR2_IMON_DATA1...LOCHNAGAR2_IMON_DATA2:
130 case LOCHNAGAR2_POWER_CTRL:
131 case LOCHNAGAR2_MICVDD_CTRL1:
132 case LOCHNAGAR2_MICVDD_CTRL2:
133 case LOCHNAGAR2_VDDCORE_CDC_CTRL1:
134 case LOCHNAGAR2_VDDCORE_CDC_CTRL2:
135 case LOCHNAGAR2_SOUNDCARD_AIF_CTRL:
136 return true;
137 default:
138 return false;
139 }
140 }
141
lochnagar2_volatile_register(struct device * dev,unsigned int reg)142 static bool lochnagar2_volatile_register(struct device *dev, unsigned int reg)
143 {
144 switch (reg) {
145 case LOCHNAGAR2_GPIO_CHANNEL1...LOCHNAGAR2_GPIO_CHANNEL16:
146 case LOCHNAGAR2_ANALOGUE_PATH_CTRL1:
147 case LOCHNAGAR2_IMON_CTRL3...LOCHNAGAR2_IMON_CTRL4:
148 case LOCHNAGAR2_IMON_DATA1...LOCHNAGAR2_IMON_DATA2:
149 return true;
150 default:
151 return false;
152 }
153 }
154
155 static const struct regmap_config lochnagar2_i2c_regmap = {
156 .reg_bits = 16,
157 .val_bits = 16,
158 .reg_format_endian = REGMAP_ENDIAN_BIG,
159 .val_format_endian = REGMAP_ENDIAN_BIG,
160
161 .max_register = 0x1F1F,
162 .readable_reg = lochnagar2_readable_register,
163 .volatile_reg = lochnagar2_volatile_register,
164
165 .cache_type = REGCACHE_MAPLE,
166 };
167
168 static const struct reg_sequence lochnagar2_patch[] = {
169 { 0x00EE, 0x0000 },
170 };
171
172 struct lochnagar_config {
173 int id;
174 const char * const name;
175 enum lochnagar_type type;
176 const struct regmap_config *regmap;
177 const struct reg_sequence *patch;
178 int npatch;
179 };
180
181 static struct lochnagar_config lochnagar_configs[] = {
182 {
183 .id = 0x50,
184 .name = "lochnagar1",
185 .type = LOCHNAGAR1,
186 .regmap = &lochnagar1_i2c_regmap,
187 .patch = lochnagar1_patch,
188 .npatch = ARRAY_SIZE(lochnagar1_patch),
189 },
190 {
191 .id = 0xCB58,
192 .name = "lochnagar2",
193 .type = LOCHNAGAR2,
194 .regmap = &lochnagar2_i2c_regmap,
195 .patch = lochnagar2_patch,
196 .npatch = ARRAY_SIZE(lochnagar2_patch),
197 },
198 };
199
200 static const struct of_device_id lochnagar_of_match[] = {
201 { .compatible = "cirrus,lochnagar1", .data = &lochnagar_configs[0] },
202 { .compatible = "cirrus,lochnagar2", .data = &lochnagar_configs[1] },
203 {},
204 };
205
lochnagar_wait_for_boot(struct regmap * regmap,unsigned int * id)206 static int lochnagar_wait_for_boot(struct regmap *regmap, unsigned int *id)
207 {
208 int i, ret;
209
210 for (i = 0; i < LOCHNAGAR_BOOT_RETRIES; ++i) {
211 msleep(LOCHNAGAR_BOOT_DELAY_MS);
212
213 /* The reset register will return the device ID when read */
214 ret = regmap_read(regmap, LOCHNAGAR_SOFTWARE_RESET, id);
215 if (!ret)
216 return ret;
217 }
218
219 return -ETIMEDOUT;
220 }
221
222 /**
223 * lochnagar_update_config - Synchronise the boards analogue configuration to
224 * the hardware.
225 *
226 * @lochnagar: A pointer to the primary core data structure.
227 *
228 * Return: Zero on success or an appropriate negative error code on failure.
229 */
lochnagar_update_config(struct lochnagar * lochnagar)230 int lochnagar_update_config(struct lochnagar *lochnagar)
231 {
232 struct regmap *regmap = lochnagar->regmap;
233 unsigned int done = LOCHNAGAR2_ANALOGUE_PATH_UPDATE_STS_MASK;
234 int timeout_ms = LOCHNAGAR_BOOT_DELAY_MS * LOCHNAGAR_BOOT_RETRIES;
235 unsigned int val = 0;
236 int ret;
237
238 lockdep_assert_held(&lochnagar->analogue_config_lock);
239
240 if (lochnagar->type != LOCHNAGAR2)
241 return 0;
242
243 /*
244 * Toggle the ANALOGUE_PATH_UPDATE bit and wait for the device to
245 * acknowledge that any outstanding changes to the analogue
246 * configuration have been applied.
247 */
248 ret = regmap_write(regmap, LOCHNAGAR2_ANALOGUE_PATH_CTRL1, 0);
249 if (ret < 0)
250 return ret;
251
252 ret = regmap_write(regmap, LOCHNAGAR2_ANALOGUE_PATH_CTRL1,
253 LOCHNAGAR2_ANALOGUE_PATH_UPDATE_MASK);
254 if (ret < 0)
255 return ret;
256
257 ret = regmap_read_poll_timeout(regmap,
258 LOCHNAGAR2_ANALOGUE_PATH_CTRL1, val,
259 (val & done), LOCHNAGAR_CONFIG_POLL_US,
260 timeout_ms * 1000);
261 if (ret < 0)
262 return ret;
263
264 return 0;
265 }
266 EXPORT_SYMBOL_GPL(lochnagar_update_config);
267
lochnagar_i2c_probe(struct i2c_client * i2c)268 static int lochnagar_i2c_probe(struct i2c_client *i2c)
269 {
270 struct device *dev = &i2c->dev;
271 const struct lochnagar_config *config = NULL;
272 struct lochnagar *lochnagar;
273 struct gpio_desc *reset, *present;
274 unsigned int val;
275 unsigned int firmwareid;
276 unsigned int devid, rev;
277 int ret;
278
279 lochnagar = devm_kzalloc(dev, sizeof(*lochnagar), GFP_KERNEL);
280 if (!lochnagar)
281 return -ENOMEM;
282
283 config = i2c_get_match_data(i2c);
284
285 lochnagar->dev = dev;
286 mutex_init(&lochnagar->analogue_config_lock);
287
288 dev_set_drvdata(dev, lochnagar);
289
290 reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
291 if (IS_ERR(reset)) {
292 ret = PTR_ERR(reset);
293 dev_err(dev, "Failed to get reset GPIO: %d\n", ret);
294 return ret;
295 }
296
297 present = devm_gpiod_get_optional(dev, "present", GPIOD_OUT_HIGH);
298 if (IS_ERR(present)) {
299 ret = PTR_ERR(present);
300 dev_err(dev, "Failed to get present GPIO: %d\n", ret);
301 return ret;
302 }
303
304 /* Leave the Lochnagar in reset for a reasonable amount of time */
305 msleep(20);
306
307 /* Bring Lochnagar out of reset */
308 gpiod_set_value_cansleep(reset, 1);
309
310 /* Identify Lochnagar */
311 lochnagar->type = config->type;
312
313 lochnagar->regmap = devm_regmap_init_i2c(i2c, config->regmap);
314 if (IS_ERR(lochnagar->regmap)) {
315 ret = PTR_ERR(lochnagar->regmap);
316 dev_err(dev, "Failed to allocate register map: %d\n", ret);
317 return ret;
318 }
319
320 /* Wait for Lochnagar to boot */
321 ret = lochnagar_wait_for_boot(lochnagar->regmap, &val);
322 if (ret < 0) {
323 dev_err(dev, "Failed to read device ID: %d\n", ret);
324 return ret;
325 }
326
327 devid = val & LOCHNAGAR_DEVICE_ID_MASK;
328 rev = val & LOCHNAGAR_REV_ID_MASK;
329
330 if (devid != config->id) {
331 dev_err(dev,
332 "ID does not match %s (expected 0x%x got 0x%x)\n",
333 config->name, config->id, devid);
334 return -ENODEV;
335 }
336
337 /* Identify firmware */
338 ret = regmap_read(lochnagar->regmap, LOCHNAGAR_FIRMWARE_ID1, &val);
339 if (ret < 0) {
340 dev_err(dev, "Failed to read firmware id 1: %d\n", ret);
341 return ret;
342 }
343
344 firmwareid = val;
345
346 ret = regmap_read(lochnagar->regmap, LOCHNAGAR_FIRMWARE_ID2, &val);
347 if (ret < 0) {
348 dev_err(dev, "Failed to read firmware id 2: %d\n", ret);
349 return ret;
350 }
351
352 firmwareid |= (val << config->regmap->val_bits);
353
354 dev_info(dev, "Found %s (0x%x) revision %u firmware 0x%.6x\n",
355 config->name, devid, rev + 1, firmwareid);
356
357 ret = regmap_register_patch(lochnagar->regmap, config->patch,
358 config->npatch);
359 if (ret < 0) {
360 dev_err(dev, "Failed to register patch: %d\n", ret);
361 return ret;
362 }
363
364 ret = devm_of_platform_populate(dev);
365 if (ret < 0) {
366 dev_err(dev, "Failed to populate child nodes: %d\n", ret);
367 return ret;
368 }
369
370 return ret;
371 }
372
373 static struct i2c_driver lochnagar_i2c_driver = {
374 .driver = {
375 .name = "lochnagar",
376 .of_match_table = lochnagar_of_match,
377 .suppress_bind_attrs = true,
378 },
379 .probe = lochnagar_i2c_probe,
380 };
381
lochnagar_i2c_init(void)382 static int __init lochnagar_i2c_init(void)
383 {
384 int ret;
385
386 ret = i2c_add_driver(&lochnagar_i2c_driver);
387 if (ret)
388 pr_err("Failed to register Lochnagar driver: %d\n", ret);
389
390 return ret;
391 }
392 subsys_initcall(lochnagar_i2c_init);
393