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/acpi.h>
9 #include <linux/dmi.h>
10 #include <linux/kconfig.h>
11 #include <linux/mfd/core.h>
12 #include <linux/module.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-usbpd-charger", },
91 { .name = "cros-usbpd-logger", },
92 };
93
94 static const struct mfd_cell cros_usbpd_notify_cells[] = {
95 { .name = "cros-usbpd-notify", },
96 };
97
98 static const struct mfd_cell cros_ec_wdt_cells[] = {
99 { .name = "cros-ec-wdt", }
100 };
101
102 static const struct mfd_cell cros_ec_led_cells[] = {
103 { .name = "cros-ec-led", },
104 };
105
106 static const struct mfd_cell cros_ec_keyboard_leds_cells[] = {
107 { .name = "cros-keyboard-leds", },
108 };
109
110 static const struct mfd_cell cros_ec_ucsi_cells[] = {
111 { .name = "cros_ec_ucsi", },
112 };
113
114 static const struct mfd_cell cros_ec_charge_control_cells[] = {
115 { .name = "cros-charge-control", },
116 };
117
118 static const struct cros_feature_to_cells cros_subdevices[] = {
119 {
120 .id = EC_FEATURE_CEC,
121 .mfd_cells = cros_ec_cec_cells,
122 .num_cells = ARRAY_SIZE(cros_ec_cec_cells),
123 },
124 {
125 .id = EC_FEATURE_GPIO,
126 .mfd_cells = cros_ec_gpio_cells,
127 .num_cells = ARRAY_SIZE(cros_ec_gpio_cells),
128 },
129 {
130 .id = EC_FEATURE_RTC,
131 .mfd_cells = cros_ec_rtc_cells,
132 .num_cells = ARRAY_SIZE(cros_ec_rtc_cells),
133 },
134 {
135 .id = EC_FEATURE_HANG_DETECT,
136 .mfd_cells = cros_ec_wdt_cells,
137 .num_cells = ARRAY_SIZE(cros_ec_wdt_cells),
138 },
139 {
140 .id = EC_FEATURE_LED,
141 .mfd_cells = cros_ec_led_cells,
142 .num_cells = ARRAY_SIZE(cros_ec_led_cells),
143 },
144 {
145 .id = EC_FEATURE_PWM_KEYB,
146 .mfd_cells = cros_ec_keyboard_leds_cells,
147 .num_cells = ARRAY_SIZE(cros_ec_keyboard_leds_cells),
148 },
149 {
150 .id = EC_FEATURE_CHARGER,
151 .mfd_cells = cros_ec_charge_control_cells,
152 .num_cells = ARRAY_SIZE(cros_ec_charge_control_cells),
153 },
154 };
155
156 static const struct mfd_cell cros_ec_platform_cells[] = {
157 { .name = "cros-ec-chardev", },
158 { .name = "cros-ec-debugfs", },
159 { .name = "cros-ec-hwmon", },
160 { .name = "cros-ec-sysfs", },
161 };
162
163 static const struct mfd_cell cros_ec_pchg_cells[] = {
164 { .name = "cros-ec-pchg", },
165 };
166
167 static const struct mfd_cell cros_ec_lightbar_cells[] = {
168 { .name = "cros-ec-lightbar", }
169 };
170
171 static const struct mfd_cell cros_ec_vbc_cells[] = {
172 { .name = "cros-ec-vbc", }
173 };
174
cros_ec_class_release(struct device * dev)175 static void cros_ec_class_release(struct device *dev)
176 {
177 kfree(to_cros_ec_dev(dev));
178 }
179
ec_device_probe(struct platform_device * pdev)180 static int ec_device_probe(struct platform_device *pdev)
181 {
182 int retval = -ENOMEM;
183 struct device_node *node;
184 struct device *dev = &pdev->dev;
185 struct cros_ec_platform *ec_platform = dev_get_platdata(dev);
186 struct cros_ec_dev *ec = kzalloc_obj(*ec);
187 struct ec_response_pchg_count pchg_count;
188 int i;
189
190 if (!ec)
191 return retval;
192
193 ec->ec_dev = dev_get_drvdata(dev->parent);
194 ec->dev = dev;
195 ec->cmd_offset = ec_platform->cmd_offset;
196 ec->features.flags[0] = -1U; /* Not cached yet */
197 ec->features.flags[1] = -1U; /* Not cached yet */
198 device_initialize(&ec->class_dev);
199
200 /*
201 * Add the class device
202 */
203 ec->class_dev.class = &cros_class;
204 ec->class_dev.parent = dev;
205 ec->class_dev.release = cros_ec_class_release;
206
207 retval = cros_ec_read_features(ec);
208 if (retval < 0)
209 goto failed;
210
211 for (i = 0; i < ARRAY_SIZE(cros_mcu_devices); i++) {
212 /*
213 * Check whether this is actually a dedicated MCU rather
214 * than an standard EC.
215 */
216 if (cros_ec_check_features(ec, cros_mcu_devices[i].id)) {
217 dev_info(dev, "CrOS %s MCU detected\n",
218 cros_mcu_devices[i].desc);
219 /*
220 * Help userspace differentiating ECs from other MCU,
221 * regardless of the probing order.
222 */
223 ec_platform->ec_name = cros_mcu_devices[i].name;
224 break;
225 }
226 }
227
228 retval = dev_set_name(&ec->class_dev, "%s", ec_platform->ec_name);
229 if (retval) {
230 dev_err(dev, "dev_set_name failed => %d\n", retval);
231 goto failed;
232 }
233
234 retval = device_add(&ec->class_dev);
235 if (retval)
236 goto failed;
237
238 dev_set_drvdata(dev, ec);
239
240 /* check whether this EC is a sensor hub. */
241 if (cros_ec_get_sensor_count(ec) > 0) {
242 retval = mfd_add_hotplug_devices(ec->dev,
243 cros_ec_sensorhub_cells,
244 ARRAY_SIZE(cros_ec_sensorhub_cells));
245 if (retval)
246 dev_err(ec->dev, "failed to add %s subdevice: %d\n",
247 cros_ec_sensorhub_cells->name, retval);
248 }
249
250 /*
251 * The following subdevices can be detected by sending the
252 * EC_FEATURE_GET_CMD Embedded Controller device.
253 */
254 for (i = 0; i < ARRAY_SIZE(cros_subdevices); i++) {
255 if (cros_ec_check_features(ec, cros_subdevices[i].id)) {
256 retval = mfd_add_hotplug_devices(ec->dev,
257 cros_subdevices[i].mfd_cells,
258 cros_subdevices[i].num_cells);
259 if (retval)
260 dev_err(ec->dev,
261 "failed to add %s subdevice: %d\n",
262 cros_subdevices[i].mfd_cells->name,
263 retval);
264 }
265 }
266
267 /*
268 * FW nodes can load cros_ec_ucsi, but early PDC devices did not define
269 * the required nodes. On PDC systems without FW nodes for cros_ec_ucsi,
270 * the driver should be added as an mfd subdevice.
271 */
272 if (cros_ec_check_features(ec, EC_FEATURE_USB_PD) &&
273 cros_ec_check_features(ec, EC_FEATURE_UCSI_PPM) &&
274 !acpi_dev_found("GOOG0021") &&
275 !of_find_compatible_node(NULL, NULL, "google,cros-ec-ucsi")) {
276 retval = mfd_add_hotplug_devices(ec->dev,
277 cros_ec_ucsi_cells,
278 ARRAY_SIZE(cros_ec_ucsi_cells));
279
280 if (retval)
281 dev_warn(ec->dev, "failed to add cros_ec_ucsi: %d\n", retval);
282 }
283
284 /*
285 * UCSI provides power supply information so we don't need to separately
286 * load the cros_usbpd_charger driver.
287 */
288 if (cros_ec_check_features(ec, EC_FEATURE_USB_PD) &&
289 !cros_ec_check_features(ec, EC_FEATURE_UCSI_PPM)) {
290 retval = mfd_add_hotplug_devices(ec->dev,
291 cros_usbpd_charger_cells,
292 ARRAY_SIZE(cros_usbpd_charger_cells));
293
294 if (retval)
295 dev_warn(ec->dev, "failed to add usbpd-charger: %d\n",
296 retval);
297 }
298
299 /*
300 * Lightbar is a special case. Newer devices support autodetection,
301 * but older ones do not.
302 */
303 if (cros_ec_check_features(ec, EC_FEATURE_LIGHTBAR) ||
304 dmi_match(DMI_PRODUCT_NAME, "Link")) {
305 retval = mfd_add_hotplug_devices(ec->dev,
306 cros_ec_lightbar_cells,
307 ARRAY_SIZE(cros_ec_lightbar_cells));
308 if (retval)
309 dev_warn(ec->dev, "failed to add lightbar: %d\n",
310 retval);
311 }
312
313 /*
314 * The PD notifier driver cell is separate since it only needs to be
315 * explicitly added on platforms that don't have the PD notifier ACPI
316 * device entry defined.
317 */
318 if (IS_ENABLED(CONFIG_OF) && ec->ec_dev->dev->of_node) {
319 if (cros_ec_check_features(ec, EC_FEATURE_USB_PD)) {
320 retval = mfd_add_hotplug_devices(ec->dev,
321 cros_usbpd_notify_cells,
322 ARRAY_SIZE(cros_usbpd_notify_cells));
323 if (retval)
324 dev_err(ec->dev,
325 "failed to add PD notify devices: %d\n",
326 retval);
327 }
328 }
329
330 /*
331 * The PCHG device cannot be detected by sending EC_FEATURE_GET_CMD, but
332 * it can be detected by querying the number of peripheral chargers.
333 */
334 retval = cros_ec_cmd(ec->ec_dev, 0, EC_CMD_PCHG_COUNT, NULL, 0,
335 &pchg_count, sizeof(pchg_count));
336 if (retval >= 0 && pchg_count.port_count) {
337 retval = mfd_add_hotplug_devices(ec->dev,
338 cros_ec_pchg_cells,
339 ARRAY_SIZE(cros_ec_pchg_cells));
340 if (retval)
341 dev_warn(ec->dev, "failed to add pchg: %d\n",
342 retval);
343 }
344
345 /*
346 * The following subdevices cannot be detected by sending the
347 * EC_FEATURE_GET_CMD to the Embedded Controller device.
348 */
349 retval = mfd_add_hotplug_devices(ec->dev, cros_ec_platform_cells,
350 ARRAY_SIZE(cros_ec_platform_cells));
351 if (retval)
352 dev_warn(ec->dev,
353 "failed to add cros-ec platform devices: %d\n",
354 retval);
355
356 /* Check whether this EC instance has a VBC NVRAM */
357 node = ec->ec_dev->dev->of_node;
358 if (of_property_read_bool(node, "google,has-vbc-nvram")) {
359 retval = mfd_add_hotplug_devices(ec->dev, cros_ec_vbc_cells,
360 ARRAY_SIZE(cros_ec_vbc_cells));
361 if (retval)
362 dev_warn(ec->dev, "failed to add VBC devices: %d\n",
363 retval);
364 }
365
366 return 0;
367
368 failed:
369 put_device(&ec->class_dev);
370 return retval;
371 }
372
ec_device_remove(struct platform_device * pdev)373 static void ec_device_remove(struct platform_device *pdev)
374 {
375 struct cros_ec_dev *ec = dev_get_drvdata(&pdev->dev);
376
377 mfd_remove_devices(ec->dev);
378 device_unregister(&ec->class_dev);
379 }
380
381 static const struct platform_device_id cros_ec_id[] = {
382 { DRV_NAME, 0 },
383 { /* sentinel */ }
384 };
385 MODULE_DEVICE_TABLE(platform, cros_ec_id);
386
387 static struct platform_driver cros_ec_dev_driver = {
388 .driver = {
389 .name = DRV_NAME,
390 },
391 .id_table = cros_ec_id,
392 .probe = ec_device_probe,
393 .remove = ec_device_remove,
394 };
395
cros_ec_dev_init(void)396 static int __init cros_ec_dev_init(void)
397 {
398 int ret;
399
400 ret = class_register(&cros_class);
401 if (ret) {
402 pr_err(CROS_EC_DEV_NAME ": failed to register device class\n");
403 return ret;
404 }
405
406 ret = platform_driver_register(&cros_ec_dev_driver);
407 if (ret) {
408 pr_warn(CROS_EC_DEV_NAME ": can't register driver: %d\n", ret);
409 class_unregister(&cros_class);
410 }
411 return ret;
412 }
413
cros_ec_dev_exit(void)414 static void __exit cros_ec_dev_exit(void)
415 {
416 platform_driver_unregister(&cros_ec_dev_driver);
417 class_unregister(&cros_class);
418 }
419
420 module_init(cros_ec_dev_init);
421 module_exit(cros_ec_dev_exit);
422
423 MODULE_AUTHOR("Bill Richardson <wfrichar@chromium.org>");
424 MODULE_DESCRIPTION("ChromeOS Embedded Controller");
425 MODULE_VERSION("1.0");
426 MODULE_LICENSE("GPL");
427