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
22static 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 */
32struct 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 */
44struct cros_feature_to_cells {
45 unsigned int id;
46 const struct mfd_cell *mfd_cells;
47 unsigned int num_cells;
48};
49
50static 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
73static const struct mfd_cell cros_ec_cec_cells[] = {
74 { .name = "cros-ec-cec", },
75};
76
77static const struct mfd_cell cros_ec_gpio_cells[] = {
78 { .name = "cros-ec-gpio", },
79};
80
81static const struct mfd_cell cros_ec_rtc_cells[] = {
82 { .name = "cros-ec-rtc", },
83};
84
85static const struct mfd_cell cros_ec_sensorhub_cells[] = {
86 { .name = "cros-ec-sensorhub", },
87};
88
89static const struct mfd_cell cros_usbpd_charger_cells[] = {
90 { .name = "cros-usbpd-charger", },
91 { .name = "cros-usbpd-logger", },
92};
93
94static const struct mfd_cell cros_usbpd_notify_cells[] = {
95 { .name = "cros-usbpd-notify", },
96};
97
98static const struct mfd_cell cros_ec_wdt_cells[] = {
99 { .name = "cros-ec-wdt", }
100};
101
102static const struct mfd_cell cros_ec_led_cells[] = {
103 { .name = "cros-ec-led", },
104};
105
106static const struct mfd_cell cros_ec_keyboard_leds_cells[] = {
107 { .name = "cros-keyboard-leds", },
108};
109
110static const struct mfd_cell cros_ec_ucsi_cells[] = {
111 { .name = "cros_ec_ucsi", },
112};
113
114static const struct mfd_cell cros_ec_charge_control_cells[] = {
115 { .name = "cros-charge-control", },
116};
117
118static 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_UCSI_PPM,
136 .mfd_cells = cros_ec_ucsi_cells,
137 .num_cells = ARRAY_SIZE(cros_ec_ucsi_cells),
138 },
139 {
140 .id = EC_FEATURE_HANG_DETECT,
141 .mfd_cells = cros_ec_wdt_cells,
142 .num_cells = ARRAY_SIZE(cros_ec_wdt_cells),
143 },
144 {
145 .id = EC_FEATURE_LED,
146 .mfd_cells = cros_ec_led_cells,
147 .num_cells = ARRAY_SIZE(cros_ec_led_cells),
148 },
149 {
150 .id = EC_FEATURE_PWM_KEYB,
151 .mfd_cells = cros_ec_keyboard_leds_cells,
152 .num_cells = ARRAY_SIZE(cros_ec_keyboard_leds_cells),
153 },
154 {
155 .id = EC_FEATURE_CHARGER,
156 .mfd_cells = cros_ec_charge_control_cells,
157 .num_cells = ARRAY_SIZE(cros_ec_charge_control_cells),
158 },
159};
160
161static const struct mfd_cell cros_ec_platform_cells[] = {
162 { .name = "cros-ec-chardev", },
163 { .name = "cros-ec-debugfs", },
164 { .name = "cros-ec-hwmon", },
165 { .name = "cros-ec-sysfs", },
166};
167
168static const struct mfd_cell cros_ec_pchg_cells[] = {
169 { .name = "cros-ec-pchg", },
170};
171
172static const struct mfd_cell cros_ec_lightbar_cells[] = {
173 { .name = "cros-ec-lightbar", }
174};
175
176static const struct mfd_cell cros_ec_vbc_cells[] = {
177 { .name = "cros-ec-vbc", }
178};
179
180static void cros_ec_class_release(struct device *dev)
181{
182 kfree(to_cros_ec_dev(dev));
183}
184
185static int ec_device_probe(struct platform_device *pdev)
186{
187 int retval = -ENOMEM;
188 struct device_node *node;
189 struct device *dev = &pdev->dev;
190 struct cros_ec_platform *ec_platform = dev_get_platdata(dev);
191 struct cros_ec_dev *ec = kzalloc(sizeof(*ec), GFP_KERNEL);
192 struct ec_response_pchg_count pchg_count;
193 int i;
194
195 if (!ec)
196 return retval;
197
198 dev_set_drvdata(dev, data: ec);
199 ec->ec_dev = dev_get_drvdata(dev: dev->parent);
200 ec->dev = dev;
201 ec->cmd_offset = ec_platform->cmd_offset;
202 ec->features.flags[0] = -1U; /* Not cached yet */
203 ec->features.flags[1] = -1U; /* Not cached yet */
204 device_initialize(dev: &ec->class_dev);
205
206 for (i = 0; i < ARRAY_SIZE(cros_mcu_devices); i++) {
207 /*
208 * Check whether this is actually a dedicated MCU rather
209 * than an standard EC.
210 */
211 if (cros_ec_check_features(ec, feature: cros_mcu_devices[i].id)) {
212 dev_info(dev, "CrOS %s MCU detected\n",
213 cros_mcu_devices[i].desc);
214 /*
215 * Help userspace differentiating ECs from other MCU,
216 * regardless of the probing order.
217 */
218 ec_platform->ec_name = cros_mcu_devices[i].name;
219 break;
220 }
221 }
222
223 /*
224 * Add the class device
225 */
226 ec->class_dev.class = &cros_class;
227 ec->class_dev.parent = dev;
228 ec->class_dev.release = cros_ec_class_release;
229
230 retval = dev_set_name(dev: &ec->class_dev, name: "%s", ec_platform->ec_name);
231 if (retval) {
232 dev_err(dev, "dev_set_name failed => %d\n", retval);
233 goto failed;
234 }
235
236 retval = device_add(dev: &ec->class_dev);
237 if (retval)
238 goto failed;
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(parent: ec->dev,
243 cells: 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, feature: cros_subdevices[i].id)) {
256 retval = mfd_add_hotplug_devices(parent: ec->dev,
257 cells: cros_subdevices[i].mfd_cells,
258 n_devs: 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 * UCSI provides power supply information so we don't need to separately
269 * load the cros_usbpd_charger driver.
270 */
271 if (cros_ec_check_features(ec, feature: EC_FEATURE_USB_PD) &&
272 !cros_ec_check_features(ec, feature: EC_FEATURE_UCSI_PPM)) {
273 retval = mfd_add_hotplug_devices(parent: ec->dev,
274 cells: cros_usbpd_charger_cells,
275 ARRAY_SIZE(cros_usbpd_charger_cells));
276
277 if (retval)
278 dev_warn(ec->dev, "failed to add usbpd-charger: %d\n",
279 retval);
280 }
281
282 /*
283 * Lightbar is a special case. Newer devices support autodetection,
284 * but older ones do not.
285 */
286 if (cros_ec_check_features(ec, feature: EC_FEATURE_LIGHTBAR) ||
287 dmi_match(f: DMI_PRODUCT_NAME, str: "Link")) {
288 retval = mfd_add_hotplug_devices(parent: ec->dev,
289 cells: cros_ec_lightbar_cells,
290 ARRAY_SIZE(cros_ec_lightbar_cells));
291 if (retval)
292 dev_warn(ec->dev, "failed to add lightbar: %d\n",
293 retval);
294 }
295
296 /*
297 * The PD notifier driver cell is separate since it only needs to be
298 * explicitly added on platforms that don't have the PD notifier ACPI
299 * device entry defined.
300 */
301 if (IS_ENABLED(CONFIG_OF) && ec->ec_dev->dev->of_node) {
302 if (cros_ec_check_features(ec, feature: EC_FEATURE_USB_PD)) {
303 retval = mfd_add_hotplug_devices(parent: ec->dev,
304 cells: cros_usbpd_notify_cells,
305 ARRAY_SIZE(cros_usbpd_notify_cells));
306 if (retval)
307 dev_err(ec->dev,
308 "failed to add PD notify devices: %d\n",
309 retval);
310 }
311 }
312
313 /*
314 * The PCHG device cannot be detected by sending EC_FEATURE_GET_CMD, but
315 * it can be detected by querying the number of peripheral chargers.
316 */
317 retval = cros_ec_cmd(ec_dev: ec->ec_dev, version: 0, EC_CMD_PCHG_COUNT, NULL, outsize: 0,
318 indata: &pchg_count, insize: sizeof(pchg_count));
319 if (retval >= 0 && pchg_count.port_count) {
320 retval = mfd_add_hotplug_devices(parent: ec->dev,
321 cells: cros_ec_pchg_cells,
322 ARRAY_SIZE(cros_ec_pchg_cells));
323 if (retval)
324 dev_warn(ec->dev, "failed to add pchg: %d\n",
325 retval);
326 }
327
328 /*
329 * The following subdevices cannot be detected by sending the
330 * EC_FEATURE_GET_CMD to the Embedded Controller device.
331 */
332 retval = mfd_add_hotplug_devices(parent: ec->dev, cells: cros_ec_platform_cells,
333 ARRAY_SIZE(cros_ec_platform_cells));
334 if (retval)
335 dev_warn(ec->dev,
336 "failed to add cros-ec platform devices: %d\n",
337 retval);
338
339 /* Check whether this EC instance has a VBC NVRAM */
340 node = ec->ec_dev->dev->of_node;
341 if (of_property_read_bool(np: node, propname: "google,has-vbc-nvram")) {
342 retval = mfd_add_hotplug_devices(parent: ec->dev, cells: cros_ec_vbc_cells,
343 ARRAY_SIZE(cros_ec_vbc_cells));
344 if (retval)
345 dev_warn(ec->dev, "failed to add VBC devices: %d\n",
346 retval);
347 }
348
349 return 0;
350
351failed:
352 put_device(dev: &ec->class_dev);
353 return retval;
354}
355
356static void ec_device_remove(struct platform_device *pdev)
357{
358 struct cros_ec_dev *ec = dev_get_drvdata(dev: &pdev->dev);
359
360 mfd_remove_devices(parent: ec->dev);
361 device_unregister(dev: &ec->class_dev);
362}
363
364static const struct platform_device_id cros_ec_id[] = {
365 { DRV_NAME, 0 },
366 { /* sentinel */ }
367};
368MODULE_DEVICE_TABLE(platform, cros_ec_id);
369
370static struct platform_driver cros_ec_dev_driver = {
371 .driver = {
372 .name = DRV_NAME,
373 },
374 .id_table = cros_ec_id,
375 .probe = ec_device_probe,
376 .remove = ec_device_remove,
377};
378
379static int __init cros_ec_dev_init(void)
380{
381 int ret;
382
383 ret = class_register(class: &cros_class);
384 if (ret) {
385 pr_err(CROS_EC_DEV_NAME ": failed to register device class\n");
386 return ret;
387 }
388
389 ret = platform_driver_register(&cros_ec_dev_driver);
390 if (ret) {
391 pr_warn(CROS_EC_DEV_NAME ": can't register driver: %d\n", ret);
392 class_unregister(class: &cros_class);
393 }
394 return ret;
395}
396
397static void __exit cros_ec_dev_exit(void)
398{
399 platform_driver_unregister(&cros_ec_dev_driver);
400 class_unregister(class: &cros_class);
401}
402
403module_init(cros_ec_dev_init);
404module_exit(cros_ec_dev_exit);
405
406MODULE_AUTHOR("Bill Richardson <wfrichar@chromium.org>");
407MODULE_DESCRIPTION("ChromeOS Embedded Controller");
408MODULE_VERSION("1.0");
409MODULE_LICENSE("GPL");
410

source code of linux/drivers/mfd/cros_ec_dev.c