1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * ChromeOS Embedded Controller
4 *
5 * Copyright (C) 2014 Google, Inc.
6 */
7
8 #include <linux/dmi.h>
9 #include <linux/kconfig.h>
10 #include <linux/mfd/core.h>
11 #include <linux/module.h>
12 #include <linux/mod_devicetable.h>
13 #include <linux/of.h>
14 #include <linux/platform_device.h>
15 #include <linux/platform_data/cros_ec_chardev.h>
16 #include <linux/platform_data/cros_ec_commands.h>
17 #include <linux/platform_data/cros_ec_proto.h>
18 #include <linux/slab.h>
19
20 #define DRV_NAME "cros-ec-dev"
21
22 static struct class cros_class = {
23 .name = "chromeos",
24 };
25
26 /**
27 * struct cros_feature_to_name - CrOS feature id to name/short description.
28 * @id: The feature identifier.
29 * @name: Device name associated with the feature id.
30 * @desc: Short name that will be displayed.
31 */
32 struct cros_feature_to_name {
33 unsigned int id;
34 const char *name;
35 const char *desc;
36 };
37
38 /**
39 * struct cros_feature_to_cells - CrOS feature id to mfd cells association.
40 * @id: The feature identifier.
41 * @mfd_cells: Pointer to the array of mfd cells that needs to be added.
42 * @num_cells: Number of mfd cells into the array.
43 */
44 struct cros_feature_to_cells {
45 unsigned int id;
46 const struct mfd_cell *mfd_cells;
47 unsigned int num_cells;
48 };
49
50 static const struct cros_feature_to_name cros_mcu_devices[] = {
51 {
52 .id = EC_FEATURE_FINGERPRINT,
53 .name = CROS_EC_DEV_FP_NAME,
54 .desc = "Fingerprint",
55 },
56 {
57 .id = EC_FEATURE_ISH,
58 .name = CROS_EC_DEV_ISH_NAME,
59 .desc = "Integrated Sensor Hub",
60 },
61 {
62 .id = EC_FEATURE_SCP,
63 .name = CROS_EC_DEV_SCP_NAME,
64 .desc = "System Control Processor",
65 },
66 {
67 .id = EC_FEATURE_TOUCHPAD,
68 .name = CROS_EC_DEV_TP_NAME,
69 .desc = "Touchpad",
70 },
71 };
72
73 static const struct mfd_cell cros_ec_cec_cells[] = {
74 { .name = "cros-ec-cec", },
75 };
76
77 static const struct mfd_cell cros_ec_gpio_cells[] = {
78 { .name = "cros-ec-gpio", },
79 };
80
81 static const struct mfd_cell cros_ec_rtc_cells[] = {
82 { .name = "cros-ec-rtc", },
83 };
84
85 static const struct mfd_cell cros_ec_sensorhub_cells[] = {
86 { .name = "cros-ec-sensorhub", },
87 };
88
89 static const struct mfd_cell cros_usbpd_charger_cells[] = {
90 { .name = "cros-charge-control", },
91 { .name = "cros-usbpd-charger", },
92 { .name = "cros-usbpd-logger", },
93 };
94
95 static const struct mfd_cell cros_usbpd_notify_cells[] = {
96 { .name = "cros-usbpd-notify", },
97 };
98
99 static const struct mfd_cell cros_ec_wdt_cells[] = {
100 { .name = "cros-ec-wdt", }
101 };
102
103 static const struct mfd_cell cros_ec_led_cells[] = {
104 { .name = "cros-ec-led", },
105 };
106
107 static const struct mfd_cell cros_ec_keyboard_leds_cells[] = {
108 { .name = "cros-keyboard-leds", },
109 };
110
111 static const struct mfd_cell cros_ec_ucsi_cells[] = {
112 { .name = "cros_ec_ucsi", },
113 };
114
115 static const struct cros_feature_to_cells cros_subdevices[] = {
116 {
117 .id = EC_FEATURE_CEC,
118 .mfd_cells = cros_ec_cec_cells,
119 .num_cells = ARRAY_SIZE(cros_ec_cec_cells),
120 },
121 {
122 .id = EC_FEATURE_GPIO,
123 .mfd_cells = cros_ec_gpio_cells,
124 .num_cells = ARRAY_SIZE(cros_ec_gpio_cells),
125 },
126 {
127 .id = EC_FEATURE_RTC,
128 .mfd_cells = cros_ec_rtc_cells,
129 .num_cells = ARRAY_SIZE(cros_ec_rtc_cells),
130 },
131 {
132 .id = EC_FEATURE_UCSI_PPM,
133 .mfd_cells = cros_ec_ucsi_cells,
134 .num_cells = ARRAY_SIZE(cros_ec_ucsi_cells),
135 },
136 {
137 .id = EC_FEATURE_HANG_DETECT,
138 .mfd_cells = cros_ec_wdt_cells,
139 .num_cells = ARRAY_SIZE(cros_ec_wdt_cells),
140 },
141 {
142 .id = EC_FEATURE_LED,
143 .mfd_cells = cros_ec_led_cells,
144 .num_cells = ARRAY_SIZE(cros_ec_led_cells),
145 },
146 {
147 .id = EC_FEATURE_PWM_KEYB,
148 .mfd_cells = cros_ec_keyboard_leds_cells,
149 .num_cells = ARRAY_SIZE(cros_ec_keyboard_leds_cells),
150 },
151 };
152
153 static const struct mfd_cell cros_ec_platform_cells[] = {
154 { .name = "cros-ec-chardev", },
155 { .name = "cros-ec-debugfs", },
156 { .name = "cros-ec-hwmon", },
157 { .name = "cros-ec-sysfs", },
158 };
159
160 static const struct mfd_cell cros_ec_pchg_cells[] = {
161 { .name = "cros-ec-pchg", },
162 };
163
164 static const struct mfd_cell cros_ec_lightbar_cells[] = {
165 { .name = "cros-ec-lightbar", }
166 };
167
168 static const struct mfd_cell cros_ec_vbc_cells[] = {
169 { .name = "cros-ec-vbc", }
170 };
171
cros_ec_class_release(struct device * dev)172 static void cros_ec_class_release(struct device *dev)
173 {
174 kfree(to_cros_ec_dev(dev));
175 }
176
ec_device_probe(struct platform_device * pdev)177 static int ec_device_probe(struct platform_device *pdev)
178 {
179 int retval = -ENOMEM;
180 struct device_node *node;
181 struct device *dev = &pdev->dev;
182 struct cros_ec_platform *ec_platform = dev_get_platdata(dev);
183 struct cros_ec_dev *ec = kzalloc(sizeof(*ec), GFP_KERNEL);
184 struct ec_response_pchg_count pchg_count;
185 int i;
186
187 if (!ec)
188 return retval;
189
190 dev_set_drvdata(dev, ec);
191 ec->ec_dev = dev_get_drvdata(dev->parent);
192 ec->dev = dev;
193 ec->cmd_offset = ec_platform->cmd_offset;
194 ec->features.flags[0] = -1U; /* Not cached yet */
195 ec->features.flags[1] = -1U; /* Not cached yet */
196 device_initialize(&ec->class_dev);
197
198 for (i = 0; i < ARRAY_SIZE(cros_mcu_devices); i++) {
199 /*
200 * Check whether this is actually a dedicated MCU rather
201 * than an standard EC.
202 */
203 if (cros_ec_check_features(ec, cros_mcu_devices[i].id)) {
204 dev_info(dev, "CrOS %s MCU detected\n",
205 cros_mcu_devices[i].desc);
206 /*
207 * Help userspace differentiating ECs from other MCU,
208 * regardless of the probing order.
209 */
210 ec_platform->ec_name = cros_mcu_devices[i].name;
211 break;
212 }
213 }
214
215 /*
216 * Add the class device
217 */
218 ec->class_dev.class = &cros_class;
219 ec->class_dev.parent = dev;
220 ec->class_dev.release = cros_ec_class_release;
221
222 retval = dev_set_name(&ec->class_dev, "%s", ec_platform->ec_name);
223 if (retval) {
224 dev_err(dev, "dev_set_name failed => %d\n", retval);
225 goto failed;
226 }
227
228 retval = device_add(&ec->class_dev);
229 if (retval)
230 goto failed;
231
232 /* check whether this EC is a sensor hub. */
233 if (cros_ec_get_sensor_count(ec) > 0) {
234 retval = mfd_add_hotplug_devices(ec->dev,
235 cros_ec_sensorhub_cells,
236 ARRAY_SIZE(cros_ec_sensorhub_cells));
237 if (retval)
238 dev_err(ec->dev, "failed to add %s subdevice: %d\n",
239 cros_ec_sensorhub_cells->name, retval);
240 }
241
242 /*
243 * The following subdevices can be detected by sending the
244 * EC_FEATURE_GET_CMD Embedded Controller device.
245 */
246 for (i = 0; i < ARRAY_SIZE(cros_subdevices); i++) {
247 if (cros_ec_check_features(ec, cros_subdevices[i].id)) {
248 retval = mfd_add_hotplug_devices(ec->dev,
249 cros_subdevices[i].mfd_cells,
250 cros_subdevices[i].num_cells);
251 if (retval)
252 dev_err(ec->dev,
253 "failed to add %s subdevice: %d\n",
254 cros_subdevices[i].mfd_cells->name,
255 retval);
256 }
257 }
258
259 /*
260 * UCSI provides power supply information so we don't need to separately
261 * load the cros_usbpd_charger driver.
262 */
263 if (cros_ec_check_features(ec, EC_FEATURE_USB_PD) &&
264 !cros_ec_check_features(ec, EC_FEATURE_UCSI_PPM)) {
265 retval = mfd_add_hotplug_devices(ec->dev,
266 cros_usbpd_charger_cells,
267 ARRAY_SIZE(cros_usbpd_charger_cells));
268
269 if (retval)
270 dev_warn(ec->dev, "failed to add usbpd-charger: %d\n",
271 retval);
272 }
273
274 /*
275 * Lightbar is a special case. Newer devices support autodetection,
276 * but older ones do not.
277 */
278 if (cros_ec_check_features(ec, EC_FEATURE_LIGHTBAR) ||
279 dmi_match(DMI_PRODUCT_NAME, "Link")) {
280 retval = mfd_add_hotplug_devices(ec->dev,
281 cros_ec_lightbar_cells,
282 ARRAY_SIZE(cros_ec_lightbar_cells));
283 if (retval)
284 dev_warn(ec->dev, "failed to add lightbar: %d\n",
285 retval);
286 }
287
288 /*
289 * The PD notifier driver cell is separate since it only needs to be
290 * explicitly added on platforms that don't have the PD notifier ACPI
291 * device entry defined.
292 */
293 if (IS_ENABLED(CONFIG_OF) && ec->ec_dev->dev->of_node) {
294 if (cros_ec_check_features(ec, EC_FEATURE_USB_PD)) {
295 retval = mfd_add_hotplug_devices(ec->dev,
296 cros_usbpd_notify_cells,
297 ARRAY_SIZE(cros_usbpd_notify_cells));
298 if (retval)
299 dev_err(ec->dev,
300 "failed to add PD notify devices: %d\n",
301 retval);
302 }
303 }
304
305 /*
306 * The PCHG device cannot be detected by sending EC_FEATURE_GET_CMD, but
307 * it can be detected by querying the number of peripheral chargers.
308 */
309 retval = cros_ec_cmd(ec->ec_dev, 0, EC_CMD_PCHG_COUNT, NULL, 0,
310 &pchg_count, sizeof(pchg_count));
311 if (retval >= 0 && pchg_count.port_count) {
312 retval = mfd_add_hotplug_devices(ec->dev,
313 cros_ec_pchg_cells,
314 ARRAY_SIZE(cros_ec_pchg_cells));
315 if (retval)
316 dev_warn(ec->dev, "failed to add pchg: %d\n",
317 retval);
318 }
319
320 /*
321 * The following subdevices cannot be detected by sending the
322 * EC_FEATURE_GET_CMD to the Embedded Controller device.
323 */
324 retval = mfd_add_hotplug_devices(ec->dev, cros_ec_platform_cells,
325 ARRAY_SIZE(cros_ec_platform_cells));
326 if (retval)
327 dev_warn(ec->dev,
328 "failed to add cros-ec platform devices: %d\n",
329 retval);
330
331 /* Check whether this EC instance has a VBC NVRAM */
332 node = ec->ec_dev->dev->of_node;
333 if (of_property_read_bool(node, "google,has-vbc-nvram")) {
334 retval = mfd_add_hotplug_devices(ec->dev, cros_ec_vbc_cells,
335 ARRAY_SIZE(cros_ec_vbc_cells));
336 if (retval)
337 dev_warn(ec->dev, "failed to add VBC devices: %d\n",
338 retval);
339 }
340
341 return 0;
342
343 failed:
344 put_device(&ec->class_dev);
345 return retval;
346 }
347
ec_device_remove(struct platform_device * pdev)348 static void ec_device_remove(struct platform_device *pdev)
349 {
350 struct cros_ec_dev *ec = dev_get_drvdata(&pdev->dev);
351
352 mfd_remove_devices(ec->dev);
353 device_unregister(&ec->class_dev);
354 }
355
356 static const struct platform_device_id cros_ec_id[] = {
357 { DRV_NAME, 0 },
358 { /* sentinel */ }
359 };
360 MODULE_DEVICE_TABLE(platform, cros_ec_id);
361
362 static struct platform_driver cros_ec_dev_driver = {
363 .driver = {
364 .name = DRV_NAME,
365 },
366 .id_table = cros_ec_id,
367 .probe = ec_device_probe,
368 .remove = ec_device_remove,
369 };
370
cros_ec_dev_init(void)371 static int __init cros_ec_dev_init(void)
372 {
373 int ret;
374
375 ret = class_register(&cros_class);
376 if (ret) {
377 pr_err(CROS_EC_DEV_NAME ": failed to register device class\n");
378 return ret;
379 }
380
381 ret = platform_driver_register(&cros_ec_dev_driver);
382 if (ret) {
383 pr_warn(CROS_EC_DEV_NAME ": can't register driver: %d\n", ret);
384 class_unregister(&cros_class);
385 }
386 return ret;
387 }
388
cros_ec_dev_exit(void)389 static void __exit cros_ec_dev_exit(void)
390 {
391 platform_driver_unregister(&cros_ec_dev_driver);
392 class_unregister(&cros_class);
393 }
394
395 module_init(cros_ec_dev_init);
396 module_exit(cros_ec_dev_exit);
397
398 MODULE_AUTHOR("Bill Richardson <wfrichar@chromium.org>");
399 MODULE_DESCRIPTION("ChromeOS Embedded Controller");
400 MODULE_VERSION("1.0");
401 MODULE_LICENSE("GPL");
402