xref: /openbmc/linux/drivers/usb/typec/ucsi/ucsi_glink.c (revision 9144f784f852f9a125cabe9927b986d909bfa439)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2019-2020, The Linux Foundation. All rights reserved.
4  * Copyright (c) 2023, Linaro Ltd
5  */
6 #include <linux/auxiliary_bus.h>
7 #include <linux/module.h>
8 #include <linux/mutex.h>
9 #include <linux/property.h>
10 #include <linux/soc/qcom/pdr.h>
11 #include <linux/usb/typec_mux.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/soc/qcom/pmic_glink.h>
14 #include "ucsi.h"
15 
16 #define PMIC_GLINK_MAX_PORTS	2
17 
18 #define UCSI_BUF_SIZE                   48
19 
20 #define MSG_TYPE_REQ_RESP               1
21 #define UCSI_BUF_SIZE                   48
22 
23 #define UC_NOTIFY_RECEIVER_UCSI         0x0
24 #define UC_UCSI_READ_BUF_REQ            0x11
25 #define UC_UCSI_WRITE_BUF_REQ           0x12
26 #define UC_UCSI_USBC_NOTIFY_IND         0x13
27 
28 struct ucsi_read_buf_req_msg {
29 	struct pmic_glink_hdr   hdr;
30 };
31 
32 struct ucsi_read_buf_resp_msg {
33 	struct pmic_glink_hdr   hdr;
34 	u8                      buf[UCSI_BUF_SIZE];
35 	u32                     ret_code;
36 };
37 
38 struct ucsi_write_buf_req_msg {
39 	struct pmic_glink_hdr   hdr;
40 	u8                      buf[UCSI_BUF_SIZE];
41 	u32                     reserved;
42 };
43 
44 struct ucsi_write_buf_resp_msg {
45 	struct pmic_glink_hdr   hdr;
46 	u32                     ret_code;
47 };
48 
49 struct ucsi_notify_ind_msg {
50 	struct pmic_glink_hdr   hdr;
51 	u32                     notification;
52 	u32                     receiver;
53 	u32                     reserved;
54 };
55 
56 struct pmic_glink_ucsi {
57 	struct device *dev;
58 
59 	struct gpio_desc *port_orientation[PMIC_GLINK_MAX_PORTS];
60 	struct typec_switch *port_switch[PMIC_GLINK_MAX_PORTS];
61 
62 	struct pmic_glink_client *client;
63 
64 	struct ucsi *ucsi;
65 	struct completion read_ack;
66 	struct completion write_ack;
67 	struct completion sync_ack;
68 	bool sync_pending;
69 	struct mutex lock;	/* protects concurrent access to PMIC Glink interface */
70 
71 	int sync_val;
72 
73 	struct work_struct notify_work;
74 	struct work_struct register_work;
75 
76 	u8 read_buf[UCSI_BUF_SIZE];
77 };
78 
pmic_glink_ucsi_read(struct ucsi * __ucsi,unsigned int offset,void * val,size_t val_len)79 static int pmic_glink_ucsi_read(struct ucsi *__ucsi, unsigned int offset,
80 				void *val, size_t val_len)
81 {
82 	struct pmic_glink_ucsi *ucsi = ucsi_get_drvdata(__ucsi);
83 	struct ucsi_read_buf_req_msg req = {};
84 	unsigned long left;
85 	int ret;
86 
87 	req.hdr.owner = PMIC_GLINK_OWNER_USBC;
88 	req.hdr.type = MSG_TYPE_REQ_RESP;
89 	req.hdr.opcode = UC_UCSI_READ_BUF_REQ;
90 
91 	mutex_lock(&ucsi->lock);
92 	memset(ucsi->read_buf, 0, sizeof(ucsi->read_buf));
93 	reinit_completion(&ucsi->read_ack);
94 
95 	ret = pmic_glink_send(ucsi->client, &req, sizeof(req));
96 	if (ret < 0) {
97 		dev_err(ucsi->dev, "failed to send UCSI read request: %d\n", ret);
98 		goto out_unlock;
99 	}
100 
101 	left = wait_for_completion_timeout(&ucsi->read_ack, 5 * HZ);
102 	if (!left) {
103 		dev_err(ucsi->dev, "timeout waiting for UCSI read response\n");
104 		ret = -ETIMEDOUT;
105 		goto out_unlock;
106 	}
107 
108 	memcpy(val, &ucsi->read_buf[offset], val_len);
109 	ret = 0;
110 
111 out_unlock:
112 	mutex_unlock(&ucsi->lock);
113 
114 	return ret;
115 }
116 
pmic_glink_ucsi_locked_write(struct pmic_glink_ucsi * ucsi,unsigned int offset,const void * val,size_t val_len)117 static int pmic_glink_ucsi_locked_write(struct pmic_glink_ucsi *ucsi, unsigned int offset,
118 					const void *val, size_t val_len)
119 {
120 	struct ucsi_write_buf_req_msg req = {};
121 	unsigned long left;
122 	int ret;
123 
124 	req.hdr.owner = PMIC_GLINK_OWNER_USBC;
125 	req.hdr.type = MSG_TYPE_REQ_RESP;
126 	req.hdr.opcode = UC_UCSI_WRITE_BUF_REQ;
127 	memcpy(&req.buf[offset], val, val_len);
128 
129 	reinit_completion(&ucsi->write_ack);
130 
131 	ret = pmic_glink_send(ucsi->client, &req, sizeof(req));
132 	if (ret < 0) {
133 		dev_err(ucsi->dev, "failed to send UCSI write request: %d\n", ret);
134 		return ret;
135 	}
136 
137 	left = wait_for_completion_timeout(&ucsi->write_ack, 5 * HZ);
138 	if (!left) {
139 		dev_err(ucsi->dev, "timeout waiting for UCSI write response\n");
140 		return -ETIMEDOUT;
141 	}
142 
143 	return 0;
144 }
145 
pmic_glink_ucsi_async_write(struct ucsi * __ucsi,unsigned int offset,const void * val,size_t val_len)146 static int pmic_glink_ucsi_async_write(struct ucsi *__ucsi, unsigned int offset,
147 				       const void *val, size_t val_len)
148 {
149 	struct pmic_glink_ucsi *ucsi = ucsi_get_drvdata(__ucsi);
150 	int ret;
151 
152 	mutex_lock(&ucsi->lock);
153 	ret = pmic_glink_ucsi_locked_write(ucsi, offset, val, val_len);
154 	mutex_unlock(&ucsi->lock);
155 
156 	return ret;
157 }
158 
pmic_glink_ucsi_sync_write(struct ucsi * __ucsi,unsigned int offset,const void * val,size_t val_len)159 static int pmic_glink_ucsi_sync_write(struct ucsi *__ucsi, unsigned int offset,
160 				      const void *val, size_t val_len)
161 {
162 	struct pmic_glink_ucsi *ucsi = ucsi_get_drvdata(__ucsi);
163 	unsigned long left;
164 	int ret;
165 
166 	/* TOFIX: Downstream forces recipient to CON when UCSI_GET_ALTERNATE_MODES command */
167 
168 	mutex_lock(&ucsi->lock);
169 	ucsi->sync_val = 0;
170 	reinit_completion(&ucsi->sync_ack);
171 	ucsi->sync_pending = true;
172 	ret = pmic_glink_ucsi_locked_write(ucsi, offset, val, val_len);
173 	mutex_unlock(&ucsi->lock);
174 
175 	left = wait_for_completion_timeout(&ucsi->sync_ack, 5 * HZ);
176 	if (!left) {
177 		dev_err(ucsi->dev, "timeout waiting for UCSI sync write response\n");
178 		/* return 0 here and let core UCSI code handle the CCI_BUSY */
179 		ret = 0;
180 	} else if (ucsi->sync_val) {
181 		dev_err(ucsi->dev, "sync write returned: %d\n", ucsi->sync_val);
182 	}
183 
184 	ucsi->sync_pending = false;
185 
186 	return ret;
187 }
188 
pmic_glink_ucsi_update_connector(struct ucsi_connector * con)189 static void pmic_glink_ucsi_update_connector(struct ucsi_connector *con)
190 {
191 	struct pmic_glink_ucsi *ucsi = ucsi_get_drvdata(con->ucsi);
192 
193 	if (con->num > PMIC_GLINK_MAX_PORTS ||
194 	    !ucsi->port_orientation[con->num - 1])
195 		return;
196 
197 	con->typec_cap.orientation_aware = true;
198 }
199 
pmic_glink_ucsi_connector_status(struct ucsi_connector * con)200 static void pmic_glink_ucsi_connector_status(struct ucsi_connector *con)
201 {
202 	struct pmic_glink_ucsi *ucsi = ucsi_get_drvdata(con->ucsi);
203 	int orientation;
204 
205 	if (con->num > PMIC_GLINK_MAX_PORTS ||
206 	    !ucsi->port_orientation[con->num - 1])
207 		return;
208 
209 	orientation = gpiod_get_value(ucsi->port_orientation[con->num - 1]);
210 	if (orientation >= 0) {
211 		typec_switch_set(ucsi->port_switch[con->num - 1],
212 				 orientation ? TYPEC_ORIENTATION_REVERSE
213 				 : TYPEC_ORIENTATION_NORMAL);
214 	}
215 }
216 
217 static const struct ucsi_operations pmic_glink_ucsi_ops = {
218 	.read = pmic_glink_ucsi_read,
219 	.sync_write = pmic_glink_ucsi_sync_write,
220 	.async_write = pmic_glink_ucsi_async_write,
221 	.update_connector = pmic_glink_ucsi_update_connector,
222 	.connector_status = pmic_glink_ucsi_connector_status,
223 };
224 
pmic_glink_ucsi_read_ack(struct pmic_glink_ucsi * ucsi,const void * data,int len)225 static void pmic_glink_ucsi_read_ack(struct pmic_glink_ucsi *ucsi, const void *data, int len)
226 {
227 	const struct ucsi_read_buf_resp_msg *resp = data;
228 
229 	if (resp->ret_code)
230 		return;
231 
232 	memcpy(ucsi->read_buf, resp->buf, UCSI_BUF_SIZE);
233 	complete(&ucsi->read_ack);
234 }
235 
pmic_glink_ucsi_write_ack(struct pmic_glink_ucsi * ucsi,const void * data,int len)236 static void pmic_glink_ucsi_write_ack(struct pmic_glink_ucsi *ucsi, const void *data, int len)
237 {
238 	const struct ucsi_write_buf_resp_msg *resp = data;
239 
240 	if (resp->ret_code)
241 		return;
242 
243 	ucsi->sync_val = resp->ret_code;
244 	complete(&ucsi->write_ack);
245 }
246 
pmic_glink_ucsi_notify(struct work_struct * work)247 static void pmic_glink_ucsi_notify(struct work_struct *work)
248 {
249 	struct pmic_glink_ucsi *ucsi = container_of(work, struct pmic_glink_ucsi, notify_work);
250 	unsigned int con_num;
251 	u32 cci;
252 	int ret;
253 
254 	ret = pmic_glink_ucsi_read(ucsi->ucsi, UCSI_CCI, &cci, sizeof(cci));
255 	if (ret) {
256 		dev_err(ucsi->dev, "failed to read CCI on notification\n");
257 		return;
258 	}
259 
260 	con_num = UCSI_CCI_CONNECTOR(cci);
261 	if (con_num)
262 		ucsi_connector_change(ucsi->ucsi, con_num);
263 
264 	if (ucsi->sync_pending &&
265 		   (cci & (UCSI_CCI_ACK_COMPLETE | UCSI_CCI_COMMAND_COMPLETE))) {
266 		complete(&ucsi->sync_ack);
267 	}
268 }
269 
pmic_glink_ucsi_register(struct work_struct * work)270 static void pmic_glink_ucsi_register(struct work_struct *work)
271 {
272 	struct pmic_glink_ucsi *ucsi = container_of(work, struct pmic_glink_ucsi, register_work);
273 
274 	ucsi_register(ucsi->ucsi);
275 }
276 
pmic_glink_ucsi_callback(const void * data,size_t len,void * priv)277 static void pmic_glink_ucsi_callback(const void *data, size_t len, void *priv)
278 {
279 	struct pmic_glink_ucsi *ucsi = priv;
280 	const struct pmic_glink_hdr *hdr = data;
281 
282 	switch (le32_to_cpu(hdr->opcode)) {
283 	case UC_UCSI_READ_BUF_REQ:
284 		pmic_glink_ucsi_read_ack(ucsi, data, len);
285 		break;
286 	case UC_UCSI_WRITE_BUF_REQ:
287 		pmic_glink_ucsi_write_ack(ucsi, data, len);
288 		break;
289 	case UC_UCSI_USBC_NOTIFY_IND:
290 		schedule_work(&ucsi->notify_work);
291 		break;
292 	};
293 }
294 
pmic_glink_ucsi_pdr_notify(void * priv,int state)295 static void pmic_glink_ucsi_pdr_notify(void *priv, int state)
296 {
297 	struct pmic_glink_ucsi *ucsi = priv;
298 
299 	if (state == SERVREG_SERVICE_STATE_UP)
300 		schedule_work(&ucsi->register_work);
301 	else if (state == SERVREG_SERVICE_STATE_DOWN)
302 		ucsi_unregister(ucsi->ucsi);
303 }
304 
pmic_glink_ucsi_destroy(void * data)305 static void pmic_glink_ucsi_destroy(void *data)
306 {
307 	struct pmic_glink_ucsi *ucsi = data;
308 
309 	/* Protect to make sure we're not in a middle of a transaction from a glink callback */
310 	mutex_lock(&ucsi->lock);
311 	ucsi_destroy(ucsi->ucsi);
312 	mutex_unlock(&ucsi->lock);
313 }
314 
pmic_glink_ucsi_probe(struct auxiliary_device * adev,const struct auxiliary_device_id * id)315 static int pmic_glink_ucsi_probe(struct auxiliary_device *adev,
316 				 const struct auxiliary_device_id *id)
317 {
318 	struct pmic_glink_ucsi *ucsi;
319 	struct device *dev = &adev->dev;
320 	struct fwnode_handle *fwnode;
321 	int ret;
322 
323 	ucsi = devm_kzalloc(dev, sizeof(*ucsi), GFP_KERNEL);
324 	if (!ucsi)
325 		return -ENOMEM;
326 
327 	ucsi->dev = dev;
328 	dev_set_drvdata(dev, ucsi);
329 
330 	INIT_WORK(&ucsi->notify_work, pmic_glink_ucsi_notify);
331 	INIT_WORK(&ucsi->register_work, pmic_glink_ucsi_register);
332 	init_completion(&ucsi->read_ack);
333 	init_completion(&ucsi->write_ack);
334 	init_completion(&ucsi->sync_ack);
335 	mutex_init(&ucsi->lock);
336 
337 	ucsi->ucsi = ucsi_create(dev, &pmic_glink_ucsi_ops);
338 	if (IS_ERR(ucsi->ucsi))
339 		return PTR_ERR(ucsi->ucsi);
340 
341 	/* Make sure we destroy *after* pmic_glink unregister */
342 	ret = devm_add_action_or_reset(dev, pmic_glink_ucsi_destroy, ucsi);
343 	if (ret)
344 		return ret;
345 
346 	ucsi_set_drvdata(ucsi->ucsi, ucsi);
347 
348 	device_for_each_child_node(dev, fwnode) {
349 		struct gpio_desc *desc;
350 		u32 port;
351 
352 		ret = fwnode_property_read_u32(fwnode, "reg", &port);
353 		if (ret < 0) {
354 			dev_err(dev, "missing reg property of %pOFn\n", fwnode);
355 			fwnode_handle_put(fwnode);
356 			return ret;
357 		}
358 
359 		if (port >= PMIC_GLINK_MAX_PORTS) {
360 			dev_warn(dev, "invalid connector number, ignoring\n");
361 			continue;
362 		}
363 
364 		desc = devm_gpiod_get_index_optional(&adev->dev, "orientation", port, GPIOD_IN);
365 
366 		/* If GPIO isn't found, continue */
367 		if (!desc)
368 			continue;
369 
370 		if (IS_ERR(desc)) {
371 			fwnode_handle_put(fwnode);
372 			return dev_err_probe(dev, PTR_ERR(desc),
373 					     "unable to acquire orientation gpio\n");
374 		}
375 		ucsi->port_orientation[port] = desc;
376 
377 		ucsi->port_switch[port] = fwnode_typec_switch_get(fwnode);
378 		if (IS_ERR(ucsi->port_switch[port]))
379 			return dev_err_probe(dev, PTR_ERR(ucsi->port_switch[port]),
380 					"failed to acquire orientation-switch\n");
381 	}
382 
383 	ucsi->client = devm_pmic_glink_client_alloc(dev, PMIC_GLINK_OWNER_USBC,
384 						    pmic_glink_ucsi_callback,
385 						    pmic_glink_ucsi_pdr_notify,
386 						    ucsi);
387 	if (IS_ERR(ucsi->client))
388 		return PTR_ERR(ucsi->client);
389 
390 	pmic_glink_client_register(ucsi->client);
391 
392 	return 0;
393 }
394 
pmic_glink_ucsi_remove(struct auxiliary_device * adev)395 static void pmic_glink_ucsi_remove(struct auxiliary_device *adev)
396 {
397 	struct pmic_glink_ucsi *ucsi = dev_get_drvdata(&adev->dev);
398 
399 	/* Unregister first to stop having read & writes */
400 	ucsi_unregister(ucsi->ucsi);
401 }
402 
403 static const struct auxiliary_device_id pmic_glink_ucsi_id_table[] = {
404 	{ .name = "pmic_glink.ucsi", },
405 	{},
406 };
407 MODULE_DEVICE_TABLE(auxiliary, pmic_glink_ucsi_id_table);
408 
409 static struct auxiliary_driver pmic_glink_ucsi_driver = {
410 	.name = "pmic_glink_ucsi",
411 	.probe = pmic_glink_ucsi_probe,
412 	.remove = pmic_glink_ucsi_remove,
413 	.id_table = pmic_glink_ucsi_id_table,
414 };
415 
416 module_auxiliary_driver(pmic_glink_ucsi_driver);
417 
418 MODULE_DESCRIPTION("Qualcomm PMIC GLINK UCSI driver");
419 MODULE_LICENSE("GPL");
420