xref: /linux/drivers/platform/arm64/qcom-hamoa-ec.c (revision 3429ae7b2f02a4a6ad40d36ee06641d433d75a1b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2024 Maya Matuszczyk <maccraft123mc@gmail.com>
4  * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
5  */
6 
7 #include <linux/bitfield.h>
8 #include <linux/bits.h>
9 #include <linux/device.h>
10 #include <linux/dev_printk.h>
11 #include <linux/err.h>
12 #include <linux/i2c.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/pm.h>
17 #include <linux/slab.h>
18 #include <linux/thermal.h>
19 
20 #define EC_SCI_EVT_READ_CMD	0x05
21 #define EC_FW_VERSION_CMD	0x0e
22 #define EC_MODERN_STANDBY_CMD	0x23
23 #define EC_FAN_DBG_CONTROL_CMD	0x30
24 #define EC_SCI_EVT_CONTROL_CMD	0x35
25 #define EC_THERMAL_CAP_CMD	0x42
26 
27 #define EC_FW_VERSION_RESP_LEN	4
28 #define EC_THERMAL_CAP_RESP_LEN	3
29 #define EC_FAN_DEBUG_CMD_LEN	6
30 #define EC_FAN_SPEED_DATA_SIZE	4
31 
32 #define EC_MODERN_STANDBY_ENTER	0x01
33 #define EC_MODERN_STANDBY_EXIT	0x00
34 
35 #define EC_FAN_DEBUG_MODE_OFF   0
36 #define EC_FAN_DEBUG_MODE_ON    BIT(0)
37 #define EC_FAN_ON               BIT(1)
38 #define EC_FAN_DEBUG_TYPE_PWM   BIT(2)
39 #define EC_MAX_FAN_CNT		2
40 #define EC_FAN_NAME_SIZE	20
41 #define EC_FAN_MAX_PWM		255
42 
43 enum qcom_ec_sci_events {
44 	EC_FAN1_STATUS_CHANGE_EVT = 0x30,
45 	EC_FAN2_STATUS_CHANGE_EVT,
46 	EC_FAN1_SPEED_CHANGE_EVT,
47 	EC_FAN2_SPEED_CHANGE_EVT,
48 	EC_NEW_LUT_SET_EVT,
49 	EC_FAN_PROFILE_SWITCH_EVT,
50 	EC_THERMISTOR_1_THRESHOLD_CROSS_EVT,
51 	EC_THERMISTOR_2_THRESHOLD_CROSS_EVT,
52 	EC_THERMISTOR_3_THRESHOLD_CROSS_EVT,
53 	/* Reserved: 0x39 - 0x3c/0x3f */
54 	EC_RECOVERED_FROM_RESET_EVT = 0x3d,
55 };
56 
57 struct qcom_ec_version {
58 	u8 main_version;
59 	u8 sub_version;
60 	u8 test_version;
61 };
62 
63 struct qcom_ec_thermal_cap {
64 #define EC_THERMAL_FAN_CNT(x)		(FIELD_GET(GENMASK(1, 0), (x)))
65 #define EC_THERMAL_FAN_TYPE(x)		(FIELD_GET(GENMASK(4, 2), (x)))
66 #define EC_THERMAL_THERMISTOR_MASK(x)	(FIELD_GET(GENMASK(7, 0), (x)))
67 	u8 fan_cnt;
68 	u8 fan_type;
69 	u8 thermistor_mask;
70 };
71 
72 struct qcom_ec_cooling_dev {
73 	struct thermal_cooling_device *cdev;
74 	struct device *parent_dev;
75 	u8 fan_id;
76 	u8 state;
77 };
78 
79 struct qcom_ec {
80 	struct qcom_ec_cooling_dev *ec_cdev;
81 	struct qcom_ec_thermal_cap thermal_cap;
82 	struct qcom_ec_version version;
83 	struct i2c_client *client;
84 };
85 
86 static int qcom_ec_read(struct qcom_ec *ec, u8 cmd, u8 resp_len, u8 *resp)
87 {
88 	int ret;
89 
90 	ret = i2c_smbus_read_i2c_block_data(ec->client, cmd, resp_len, resp);
91 	if (ret < 0)
92 		return ret;
93 	else if (ret == 0 || ret == 0xff)
94 		return -EOPNOTSUPP;
95 
96 	if (resp[0] >= resp_len)
97 		return -EINVAL;
98 
99 	return 0;
100 }
101 
102 /*
103  * EC Device Firmware Version:
104  *
105  * Read Response:
106  * ----------------------------------------------------------------------
107  * | Offset	| Name		| Description				|
108  * ----------------------------------------------------------------------
109  * | 0x00	| Byte count	| Number of bytes in response		|
110  * |		|		| (excluding byte count)		|
111  * ----------------------------------------------------------------------
112  * | 0x01	| Test-version	| Test-version of EC firmware		|
113  * ----------------------------------------------------------------------
114  * | 0x02	| Sub-version	| Sub-version of EC firmware		|
115  * ----------------------------------------------------------------------
116  * | 0x03	| Main-version	| Main-version of EC firmware		|
117  * ----------------------------------------------------------------------
118  *
119  */
120 static int qcom_ec_read_fw_version(struct device *dev)
121 {
122 	struct i2c_client *client = to_i2c_client(dev);
123 	struct qcom_ec *ec = i2c_get_clientdata(client);
124 	struct qcom_ec_version *version = &ec->version;
125 	u8 resp[EC_FW_VERSION_RESP_LEN];
126 	int ret;
127 
128 	ret = qcom_ec_read(ec, EC_FW_VERSION_CMD, EC_FW_VERSION_RESP_LEN, resp);
129 	if (ret < 0)
130 		return ret;
131 
132 	version->main_version = resp[3];
133 	version->sub_version = resp[2];
134 	version->test_version = resp[1];
135 
136 	dev_dbg(dev, "EC Version %d.%d.%d\n",
137 		version->main_version, version->sub_version, version->test_version);
138 
139 	return 0;
140 }
141 
142 /*
143  * EC Device Thermal Capabilities:
144  *
145  * Read Response:
146  * ------------------------------------------------------------------------------
147  * | Offset		| Name		| Description				|
148  * ------------------------------------------------------------------------------
149  * | 0x00		| Byte count	| Number of bytes in response		|
150  * |			|		| (excluding byte count)		|
151  * ------------------------------------------------------------------------------
152  * | 0x02 (LSB)		| EC Thermal	| Bit 0-1: Number of fans		|
153  * | 0x03		| Capabilities	| Bit 2-4: Type of fan			|
154  * |			|		| Bit 5-6: Reserved			|
155  * |			|		| Bit 7: Data Valid/Invalid		|
156  * |			|		|	 (Valid - 1, Invalid - 0)	|
157  * |			|		| Bit 8-15: Thermistor 0 - 7 presence	|
158  * |			|		|	    (1 present, 0 absent)	|
159  * ------------------------------------------------------------------------------
160  *
161  */
162 static int qcom_ec_thermal_capabilities(struct device *dev)
163 {
164 	struct i2c_client *client = to_i2c_client(dev);
165 	struct qcom_ec *ec = i2c_get_clientdata(client);
166 	struct qcom_ec_thermal_cap *cap = &ec->thermal_cap;
167 	u8 resp[EC_THERMAL_CAP_RESP_LEN];
168 	int ret;
169 
170 	ret = qcom_ec_read(ec, EC_THERMAL_CAP_CMD, EC_THERMAL_CAP_RESP_LEN, resp);
171 	if (ret < 0)
172 		return ret;
173 
174 	cap->fan_cnt = min(EC_MAX_FAN_CNT, EC_THERMAL_FAN_CNT(resp[1]));
175 	cap->fan_type = EC_THERMAL_FAN_TYPE(resp[1]);
176 	cap->thermistor_mask = EC_THERMAL_THERMISTOR_MASK(resp[2]);
177 
178 	dev_dbg(dev, "Fan count: %d Fan Type: %d Thermistor Mask: %x\n",
179 		cap->fan_cnt, cap->fan_type, cap->thermistor_mask);
180 
181 	return 0;
182 }
183 
184 static irqreturn_t qcom_ec_irq(int irq, void *data)
185 {
186 	struct qcom_ec *ec = data;
187 	struct device *dev = &ec->client->dev;
188 	int val;
189 
190 	val = i2c_smbus_read_byte_data(ec->client, EC_SCI_EVT_READ_CMD);
191 	if (val < 0) {
192 		dev_err_ratelimited(dev, "Failed to read EC SCI Event: %d\n", val);
193 		return IRQ_HANDLED;
194 	}
195 
196 	switch (val) {
197 	case EC_FAN1_STATUS_CHANGE_EVT:
198 		dev_dbg_ratelimited(dev, "Fan1 status changed\n");
199 		break;
200 	case EC_FAN2_STATUS_CHANGE_EVT:
201 		dev_dbg_ratelimited(dev, "Fan2 status changed\n");
202 		break;
203 	case EC_FAN1_SPEED_CHANGE_EVT:
204 		dev_dbg_ratelimited(dev, "Fan1 speed crossed low/high trip point\n");
205 		break;
206 	case EC_FAN2_SPEED_CHANGE_EVT:
207 		dev_dbg_ratelimited(dev, "Fan2 speed crossed low/high trip point\n");
208 		break;
209 	case EC_NEW_LUT_SET_EVT:
210 		dev_dbg_ratelimited(dev, "New LUT set\n");
211 		break;
212 	case EC_FAN_PROFILE_SWITCH_EVT:
213 		dev_dbg_ratelimited(dev, "FAN Profile switched\n");
214 		break;
215 	case EC_THERMISTOR_1_THRESHOLD_CROSS_EVT:
216 		dev_dbg_ratelimited(dev, "Thermistor 1 threshold crossed\n");
217 		break;
218 	case EC_THERMISTOR_2_THRESHOLD_CROSS_EVT:
219 		dev_dbg_ratelimited(dev, "Thermistor 2 threshold crossed\n");
220 		break;
221 	case EC_THERMISTOR_3_THRESHOLD_CROSS_EVT:
222 		dev_dbg_ratelimited(dev, "Thermistor 3 threshold crossed\n");
223 		break;
224 	case EC_RECOVERED_FROM_RESET_EVT:
225 		dev_dbg_ratelimited(dev, "EC recovered from reset\n");
226 		break;
227 	default:
228 		dev_notice_ratelimited(dev, "Unknown EC event: %d\n", val);
229 		break;
230 	}
231 
232 	return IRQ_HANDLED;
233 }
234 
235 static int qcom_ec_sci_evt_control(struct device *dev, bool enable)
236 {
237 	struct i2c_client *client = to_i2c_client(dev);
238 
239 	return i2c_smbus_write_byte_data(client, EC_SCI_EVT_CONTROL_CMD, enable ? 1 : 0);
240 }
241 
242 static int qcom_ec_fan_get_max_state(struct thermal_cooling_device *cdev, unsigned long *state)
243 {
244 	*state = EC_FAN_MAX_PWM;
245 
246 	return 0;
247 }
248 
249 static int qcom_ec_fan_get_cur_state(struct thermal_cooling_device *cdev, unsigned long *state)
250 {
251 	struct qcom_ec_cooling_dev *ec_cdev = cdev->devdata;
252 
253 	*state = ec_cdev->state;
254 
255 	return 0;
256 }
257 
258 /*
259  * Fan Debug control command:
260  *
261  * Command Payload:
262  * --------------------------------------------------------------------------------------
263  * | Offset		| Name		| Description					|
264  * --------------------------------------------------------------------------------------
265  * | 0x00		| Command	| Fan control command				|
266  * --------------------------------------------------------------------------------------
267  * | 0x01		| Fan ID	| 0x1 : Fan 1					|
268  * |			|		| 0x2 : Fan 2					|
269  * --------------------------------------------------------------------------------------
270  * | 0x02		| Byte count = 4| Size of data to set fan speed			|
271  * --------------------------------------------------------------------------------------
272  * | 0x03		| Mode		| Bit 0: Debug Mode On/Off (0 - OFF, 1 - ON )	|
273  * |			|		| Bit 1: Fan On/Off (0 - Off, 1 - ON)		|
274  * |			|		| Bit 2: Debug Type (0 - RPM, 1 - PWM)		|
275  * --------------------------------------------------------------------------------------
276  * | 0x04 (LSB)		| Speed in RPM	| RPM value, if mode selected is RPM		|
277  * | 0x05		|		|						|
278  * --------------------------------------------------------------------------------------
279  * | 0x06		| Speed in PWM	| PWM value, if mode selected is PWM (0 - 255)	|
280  * ______________________________________________________________________________________
281  *
282  */
283 static int qcom_ec_fan_debug_mode_off(struct qcom_ec_cooling_dev *ec_cdev)
284 {
285 	struct device *dev = ec_cdev->parent_dev;
286 	struct i2c_client *client = to_i2c_client(dev);
287 	u8 request[6] = { ec_cdev->fan_id, EC_FAN_SPEED_DATA_SIZE,
288 			  EC_FAN_DEBUG_MODE_OFF, 0, 0, 0 };
289 	int ret;
290 
291 	ret = i2c_smbus_write_i2c_block_data(client, EC_FAN_DBG_CONTROL_CMD,
292 					     sizeof(request), request);
293 	if (ret) {
294 		dev_err(dev, "Failed to turn off fan%d debug mode: %d\n",
295 			ec_cdev->fan_id, ret);
296 	}
297 
298 	return ret;
299 }
300 
301 static int qcom_ec_fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
302 {
303 	struct qcom_ec_cooling_dev *ec_cdev = cdev->devdata;
304 	struct device *dev = ec_cdev->parent_dev;
305 	struct i2c_client *client = to_i2c_client(dev);
306 	u8 request[6] = { ec_cdev->fan_id, EC_FAN_SPEED_DATA_SIZE,
307 			  EC_FAN_DEBUG_MODE_ON | EC_FAN_ON | EC_FAN_DEBUG_TYPE_PWM,
308 			  0, 0, state };
309 	int ret;
310 
311 	ret = i2c_smbus_write_i2c_block_data(client, EC_FAN_DBG_CONTROL_CMD,
312 					     sizeof(request), request);
313 	if (ret) {
314 		dev_err(dev, "Failed to set fan pwm: %d\n", ret);
315 		return ret;
316 	}
317 
318 	ec_cdev->state = state;
319 
320 	return 0;
321 }
322 
323 static const struct thermal_cooling_device_ops qcom_ec_thermal_ops = {
324 	.get_max_state = qcom_ec_fan_get_max_state,
325 	.get_cur_state = qcom_ec_fan_get_cur_state,
326 	.set_cur_state = qcom_ec_fan_set_cur_state,
327 };
328 
329 static int qcom_ec_resume(struct device *dev)
330 {
331 	struct i2c_client *client = to_i2c_client(dev);
332 
333 	return i2c_smbus_write_byte_data(client, EC_MODERN_STANDBY_CMD,
334 					 EC_MODERN_STANDBY_EXIT);
335 }
336 
337 static int qcom_ec_suspend(struct device *dev)
338 {
339 	struct i2c_client *client = to_i2c_client(dev);
340 
341 	return i2c_smbus_write_byte_data(client, EC_MODERN_STANDBY_CMD,
342 					 EC_MODERN_STANDBY_ENTER);
343 }
344 
345 static int qcom_ec_probe(struct i2c_client *client)
346 {
347 	struct device *dev = &client->dev;
348 	struct qcom_ec *ec;
349 	unsigned int i;
350 	int ret;
351 
352 	ec = devm_kzalloc(dev, sizeof(*ec), GFP_KERNEL);
353 	if (!ec)
354 		return -ENOMEM;
355 
356 	ec->client = client;
357 
358 	ret = devm_request_threaded_irq(dev, client->irq, NULL, qcom_ec_irq,
359 					IRQF_ONESHOT, "qcom_ec", ec);
360 	if (ret < 0)
361 		return ret;
362 
363 	i2c_set_clientdata(client, ec);
364 
365 	ret = qcom_ec_read_fw_version(dev);
366 	if (ret < 0)
367 		return dev_err_probe(dev, ret, "Failed to read EC firmware version\n");
368 
369 	ret = qcom_ec_sci_evt_control(dev, true);
370 	if (ret < 0)
371 		return dev_err_probe(dev, ret, "Failed to enable SCI events\n");
372 
373 	ret = qcom_ec_thermal_capabilities(dev);
374 	if (ret < 0)
375 		return dev_err_probe(dev, ret, "Failed to read thermal capabilities\n");
376 
377 	if (ec->thermal_cap.fan_cnt == 0) {
378 		dev_warn(dev, FW_BUG "Failed to get fan count, firmware update required\n");
379 		return 0;
380 	}
381 
382 	ec->ec_cdev = devm_kcalloc(dev, ec->thermal_cap.fan_cnt, sizeof(*ec->ec_cdev), GFP_KERNEL);
383 	if (!ec->ec_cdev)
384 		return -ENOMEM;
385 
386 	for (i = 0; i < ec->thermal_cap.fan_cnt; i++) {
387 		struct qcom_ec_cooling_dev *ec_cdev = &ec->ec_cdev[i];
388 		char name[EC_FAN_NAME_SIZE];
389 
390 		scnprintf(name, sizeof(name), "qcom_ec_fan_%u", i);
391 		ec_cdev->fan_id = i + 1;
392 		ec_cdev->parent_dev = dev;
393 
394 		ec_cdev->cdev = devm_thermal_of_cooling_device_register(dev, NULL, name, ec_cdev,
395 									&qcom_ec_thermal_ops);
396 		if (IS_ERR(ec_cdev->cdev)) {
397 			return dev_err_probe(dev, PTR_ERR(ec_cdev->cdev),
398 					     "Failed to register fan%d cooling device\n", i);
399 		}
400 	}
401 
402 	return 0;
403 }
404 
405 static void qcom_ec_remove(struct i2c_client *client)
406 {
407 	struct qcom_ec *ec = i2c_get_clientdata(client);
408 	struct device *dev = &client->dev;
409 	int ret;
410 
411 	ret = qcom_ec_sci_evt_control(dev, false);
412 	if (ret < 0)
413 		dev_err(dev, "Failed to disable SCI events: %d\n", ret);
414 
415 	for (int i = 0; i < ec->thermal_cap.fan_cnt; i++) {
416 		struct qcom_ec_cooling_dev *ec_cdev = &ec->ec_cdev[i];
417 
418 		qcom_ec_fan_debug_mode_off(ec_cdev);
419 	}
420 }
421 
422 static const struct of_device_id qcom_ec_of_match[] = {
423 	{ .compatible = "qcom,hamoa-crd-ec" },
424 	{}
425 };
426 MODULE_DEVICE_TABLE(of, qcom_ec_of_match);
427 
428 static const struct i2c_device_id qcom_ec_i2c_id_table[] = {
429 	{ "qcom-hamoa-ec", },
430 	{}
431 };
432 MODULE_DEVICE_TABLE(i2c, qcom_ec_i2c_id_table);
433 
434 static DEFINE_SIMPLE_DEV_PM_OPS(qcom_ec_pm_ops,
435 		qcom_ec_suspend,
436 		qcom_ec_resume);
437 
438 static struct i2c_driver qcom_ec_i2c_driver = {
439 	.driver = {
440 		.name = "qcom-hamoa-ec",
441 		.of_match_table = qcom_ec_of_match,
442 		.pm = &qcom_ec_pm_ops,
443 	},
444 	.probe = qcom_ec_probe,
445 	.remove = qcom_ec_remove,
446 	.id_table = qcom_ec_i2c_id_table,
447 };
448 module_i2c_driver(qcom_ec_i2c_driver);
449 
450 MODULE_DESCRIPTION("QCOM Hamoa Embedded Controller");
451 MODULE_LICENSE("GPL");
452