xref: /linux/drivers/soc/qcom/pmic_glink.c (revision ab93e0dd72c37d378dd936f031ffb83ff2bd87ce)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2019-2020, The Linux Foundation. All rights reserved.
4  * Copyright (c) 2022, Linaro Ltd
5  */
6 #include <linux/auxiliary_bus.h>
7 #include <linux/cleanup.h>
8 #include <linux/delay.h>
9 #include <linux/module.h>
10 #include <linux/of.h>
11 #include <linux/platform_device.h>
12 #include <linux/rpmsg.h>
13 #include <linux/slab.h>
14 #include <linux/soc/qcom/pdr.h>
15 #include <linux/soc/qcom/pmic_glink.h>
16 #include <linux/spinlock.h>
17 
18 #define PMIC_GLINK_SEND_TIMEOUT (5 * HZ)
19 
20 enum {
21 	PMIC_GLINK_CLIENT_BATT = 0,
22 	PMIC_GLINK_CLIENT_ALTMODE,
23 	PMIC_GLINK_CLIENT_UCSI,
24 };
25 
26 struct pmic_glink {
27 	struct device *dev;
28 	struct pdr_handle *pdr;
29 
30 	struct rpmsg_endpoint *ept;
31 
32 	unsigned long client_mask;
33 
34 	struct auxiliary_device altmode_aux;
35 	struct auxiliary_device ps_aux;
36 	struct auxiliary_device ucsi_aux;
37 
38 	/* serializing client_state and pdr_state updates */
39 	struct mutex state_lock;
40 	unsigned int client_state;
41 	unsigned int pdr_state;
42 
43 	/* serializing clients list updates */
44 	spinlock_t client_lock;
45 	struct list_head clients;
46 };
47 
48 static struct pmic_glink *__pmic_glink;
49 static DEFINE_MUTEX(__pmic_glink_lock);
50 
51 struct pmic_glink_client {
52 	struct list_head node;
53 
54 	struct pmic_glink *pg;
55 	unsigned int id;
56 
57 	void (*cb)(const void *data, size_t len, void *priv);
58 	void (*pdr_notify)(void *priv, int state);
59 	void *priv;
60 };
61 
_devm_pmic_glink_release_client(struct device * dev,void * res)62 static void _devm_pmic_glink_release_client(struct device *dev, void *res)
63 {
64 	struct pmic_glink_client *client = (struct pmic_glink_client *)res;
65 	struct pmic_glink *pg = client->pg;
66 	unsigned long flags;
67 
68 	spin_lock_irqsave(&pg->client_lock, flags);
69 	list_del(&client->node);
70 	spin_unlock_irqrestore(&pg->client_lock, flags);
71 }
72 
devm_pmic_glink_client_alloc(struct device * dev,unsigned int id,void (* cb)(const void *,size_t,void *),void (* pdr)(void *,int),void * priv)73 struct pmic_glink_client *devm_pmic_glink_client_alloc(struct device *dev,
74 						       unsigned int id,
75 						       void (*cb)(const void *, size_t, void *),
76 						       void (*pdr)(void *, int),
77 						       void *priv)
78 {
79 	struct pmic_glink_client *client;
80 	struct pmic_glink *pg = dev_get_drvdata(dev->parent);
81 
82 	client = devres_alloc(_devm_pmic_glink_release_client, sizeof(*client), GFP_KERNEL);
83 	if (!client)
84 		return ERR_PTR(-ENOMEM);
85 
86 	client->pg = pg;
87 	client->id = id;
88 	client->cb = cb;
89 	client->pdr_notify = pdr;
90 	client->priv = priv;
91 	INIT_LIST_HEAD(&client->node);
92 
93 	devres_add(dev, client);
94 
95 	return client;
96 }
97 EXPORT_SYMBOL_GPL(devm_pmic_glink_client_alloc);
98 
pmic_glink_client_register(struct pmic_glink_client * client)99 void pmic_glink_client_register(struct pmic_glink_client *client)
100 {
101 	struct pmic_glink *pg = client->pg;
102 	unsigned long flags;
103 
104 	guard(mutex)(&pg->state_lock);
105 	spin_lock_irqsave(&pg->client_lock, flags);
106 
107 	list_add(&client->node, &pg->clients);
108 	client->pdr_notify(client->priv, pg->client_state);
109 
110 	spin_unlock_irqrestore(&pg->client_lock, flags);
111 }
112 EXPORT_SYMBOL_GPL(pmic_glink_client_register);
113 
pmic_glink_send(struct pmic_glink_client * client,void * data,size_t len)114 int pmic_glink_send(struct pmic_glink_client *client, void *data, size_t len)
115 {
116 	struct pmic_glink *pg = client->pg;
117 	bool timeout_reached = false;
118 	unsigned long start;
119 	int ret;
120 
121 	guard(mutex)(&pg->state_lock);
122 	if (!pg->ept) {
123 		return -ECONNRESET;
124 	}
125 
126 	start = jiffies;
127 	for (;;) {
128 		ret = rpmsg_send(pg->ept, data, len);
129 		if (ret != -EAGAIN)
130 			break;
131 
132 		if (timeout_reached) {
133 			ret = -ETIMEDOUT;
134 			break;
135 		}
136 
137 		usleep_range(1000, 5000);
138 		timeout_reached = time_after(jiffies, start + PMIC_GLINK_SEND_TIMEOUT);
139 	}
140 
141 	return ret;
142 }
143 EXPORT_SYMBOL_GPL(pmic_glink_send);
144 
pmic_glink_rpmsg_callback(struct rpmsg_device * rpdev,void * data,int len,void * priv,u32 addr)145 static int pmic_glink_rpmsg_callback(struct rpmsg_device *rpdev, void *data,
146 				     int len, void *priv, u32 addr)
147 {
148 	struct pmic_glink_client *client;
149 	struct pmic_glink_hdr *hdr;
150 	struct pmic_glink *pg = dev_get_drvdata(&rpdev->dev);
151 	unsigned long flags;
152 
153 	if (len < sizeof(*hdr)) {
154 		dev_warn(pg->dev, "ignoring truncated message\n");
155 		return 0;
156 	}
157 
158 	hdr = data;
159 
160 	spin_lock_irqsave(&pg->client_lock, flags);
161 	list_for_each_entry(client, &pg->clients, node) {
162 		if (client->id == le32_to_cpu(hdr->owner))
163 			client->cb(data, len, client->priv);
164 	}
165 	spin_unlock_irqrestore(&pg->client_lock, flags);
166 
167 	return 0;
168 }
169 
pmic_glink_aux_release(struct device * dev)170 static void pmic_glink_aux_release(struct device *dev)
171 {
172 	of_node_put(dev->of_node);
173 }
174 
pmic_glink_add_aux_device(struct pmic_glink * pg,struct auxiliary_device * aux,const char * name)175 static int pmic_glink_add_aux_device(struct pmic_glink *pg,
176 				     struct auxiliary_device *aux,
177 				     const char *name)
178 {
179 	struct device *parent = pg->dev;
180 	int ret;
181 
182 	aux->name = name;
183 	aux->dev.parent = parent;
184 	aux->dev.release = pmic_glink_aux_release;
185 	device_set_of_node_from_dev(&aux->dev, parent);
186 	ret = auxiliary_device_init(aux);
187 	if (ret) {
188 		of_node_put(aux->dev.of_node);
189 		return ret;
190 	}
191 
192 	ret = auxiliary_device_add(aux);
193 	if (ret)
194 		auxiliary_device_uninit(aux);
195 
196 	return ret;
197 }
198 
pmic_glink_del_aux_device(struct pmic_glink * pg,struct auxiliary_device * aux)199 static void pmic_glink_del_aux_device(struct pmic_glink *pg,
200 				      struct auxiliary_device *aux)
201 {
202 	auxiliary_device_delete(aux);
203 	auxiliary_device_uninit(aux);
204 }
205 
pmic_glink_state_notify_clients(struct pmic_glink * pg)206 static void pmic_glink_state_notify_clients(struct pmic_glink *pg)
207 {
208 	struct pmic_glink_client *client;
209 	unsigned int new_state = pg->client_state;
210 	unsigned long flags;
211 
212 	if (pg->client_state != SERVREG_SERVICE_STATE_UP) {
213 		if (pg->pdr_state == SERVREG_SERVICE_STATE_UP && pg->ept)
214 			new_state = SERVREG_SERVICE_STATE_UP;
215 	} else {
216 		if (pg->pdr_state == SERVREG_SERVICE_STATE_DOWN || !pg->ept)
217 			new_state = SERVREG_SERVICE_STATE_DOWN;
218 	}
219 
220 	if (new_state != pg->client_state) {
221 		spin_lock_irqsave(&pg->client_lock, flags);
222 		list_for_each_entry(client, &pg->clients, node)
223 			client->pdr_notify(client->priv, new_state);
224 		spin_unlock_irqrestore(&pg->client_lock, flags);
225 		pg->client_state = new_state;
226 	}
227 }
228 
pmic_glink_pdr_callback(int state,char * svc_path,void * priv)229 static void pmic_glink_pdr_callback(int state, char *svc_path, void *priv)
230 {
231 	struct pmic_glink *pg = priv;
232 
233 	guard(mutex)(&pg->state_lock);
234 	pg->pdr_state = state;
235 
236 	pmic_glink_state_notify_clients(pg);
237 }
238 
pmic_glink_rpmsg_probe(struct rpmsg_device * rpdev)239 static int pmic_glink_rpmsg_probe(struct rpmsg_device *rpdev)
240 {
241 	struct pmic_glink *pg;
242 
243 	guard(mutex)(&__pmic_glink_lock);
244 	pg = __pmic_glink;
245 	if (!pg)
246 		return dev_err_probe(&rpdev->dev, -ENODEV, "no pmic_glink device to attach to\n");
247 
248 	dev_set_drvdata(&rpdev->dev, pg);
249 
250 	guard(mutex)(&pg->state_lock);
251 	pg->ept = rpdev->ept;
252 	pmic_glink_state_notify_clients(pg);
253 
254 	return 0;
255 }
256 
pmic_glink_rpmsg_remove(struct rpmsg_device * rpdev)257 static void pmic_glink_rpmsg_remove(struct rpmsg_device *rpdev)
258 {
259 	struct pmic_glink *pg;
260 
261 	guard(mutex)(&__pmic_glink_lock);
262 	pg = __pmic_glink;
263 	if (!pg)
264 		return;
265 
266 	guard(mutex)(&pg->state_lock);
267 	pg->ept = NULL;
268 	pmic_glink_state_notify_clients(pg);
269 }
270 
271 static const struct rpmsg_device_id pmic_glink_rpmsg_id_match[] = {
272 	{ "PMIC_RTR_ADSP_APPS" },
273 	{}
274 };
275 
276 static struct rpmsg_driver pmic_glink_rpmsg_driver = {
277 	.probe = pmic_glink_rpmsg_probe,
278 	.remove = pmic_glink_rpmsg_remove,
279 	.callback = pmic_glink_rpmsg_callback,
280 	.id_table = pmic_glink_rpmsg_id_match,
281 	.drv  = {
282 		.name  = "qcom_pmic_glink_rpmsg",
283 	},
284 };
285 
pmic_glink_probe(struct platform_device * pdev)286 static int pmic_glink_probe(struct platform_device *pdev)
287 {
288 	const unsigned long *match_data;
289 	struct pdr_service *service;
290 	struct pmic_glink *pg;
291 	int ret;
292 
293 	pg = devm_kzalloc(&pdev->dev, sizeof(*pg), GFP_KERNEL);
294 	if (!pg)
295 		return -ENOMEM;
296 
297 	dev_set_drvdata(&pdev->dev, pg);
298 
299 	pg->dev = &pdev->dev;
300 
301 	INIT_LIST_HEAD(&pg->clients);
302 	spin_lock_init(&pg->client_lock);
303 	mutex_init(&pg->state_lock);
304 
305 	match_data = (unsigned long *)of_device_get_match_data(&pdev->dev);
306 	if (!match_data)
307 		return -EINVAL;
308 
309 	pg->client_mask = *match_data;
310 
311 	pg->pdr = pdr_handle_alloc(pmic_glink_pdr_callback, pg);
312 	if (IS_ERR(pg->pdr)) {
313 		ret = dev_err_probe(&pdev->dev, PTR_ERR(pg->pdr),
314 				    "failed to initialize pdr\n");
315 		return ret;
316 	}
317 
318 	if (pg->client_mask & BIT(PMIC_GLINK_CLIENT_UCSI)) {
319 		ret = pmic_glink_add_aux_device(pg, &pg->ucsi_aux, "ucsi");
320 		if (ret)
321 			goto out_release_pdr_handle;
322 	}
323 	if (pg->client_mask & BIT(PMIC_GLINK_CLIENT_ALTMODE)) {
324 		ret = pmic_glink_add_aux_device(pg, &pg->altmode_aux, "altmode");
325 		if (ret)
326 			goto out_release_ucsi_aux;
327 	}
328 	if (pg->client_mask & BIT(PMIC_GLINK_CLIENT_BATT)) {
329 		ret = pmic_glink_add_aux_device(pg, &pg->ps_aux, "power-supply");
330 		if (ret)
331 			goto out_release_altmode_aux;
332 	}
333 
334 	service = pdr_add_lookup(pg->pdr, "tms/servreg", "msm/adsp/charger_pd");
335 	if (IS_ERR(service)) {
336 		ret = dev_err_probe(&pdev->dev, PTR_ERR(service),
337 				    "failed adding pdr lookup for charger_pd\n");
338 		goto out_release_aux_devices;
339 	}
340 
341 	mutex_lock(&__pmic_glink_lock);
342 	__pmic_glink = pg;
343 	mutex_unlock(&__pmic_glink_lock);
344 
345 	return 0;
346 
347 out_release_aux_devices:
348 	if (pg->client_mask & BIT(PMIC_GLINK_CLIENT_BATT))
349 		pmic_glink_del_aux_device(pg, &pg->ps_aux);
350 out_release_altmode_aux:
351 	if (pg->client_mask & BIT(PMIC_GLINK_CLIENT_ALTMODE))
352 		pmic_glink_del_aux_device(pg, &pg->altmode_aux);
353 out_release_ucsi_aux:
354 	if (pg->client_mask & BIT(PMIC_GLINK_CLIENT_UCSI))
355 		pmic_glink_del_aux_device(pg, &pg->ucsi_aux);
356 out_release_pdr_handle:
357 	pdr_handle_release(pg->pdr);
358 
359 	return ret;
360 }
361 
pmic_glink_remove(struct platform_device * pdev)362 static void pmic_glink_remove(struct platform_device *pdev)
363 {
364 	struct pmic_glink *pg = dev_get_drvdata(&pdev->dev);
365 
366 	pdr_handle_release(pg->pdr);
367 
368 	if (pg->client_mask & BIT(PMIC_GLINK_CLIENT_BATT))
369 		pmic_glink_del_aux_device(pg, &pg->ps_aux);
370 	if (pg->client_mask & BIT(PMIC_GLINK_CLIENT_ALTMODE))
371 		pmic_glink_del_aux_device(pg, &pg->altmode_aux);
372 	if (pg->client_mask & BIT(PMIC_GLINK_CLIENT_UCSI))
373 		pmic_glink_del_aux_device(pg, &pg->ucsi_aux);
374 
375 	guard(mutex)(&__pmic_glink_lock);
376 	__pmic_glink = NULL;
377 }
378 
379 static const unsigned long pmic_glink_sm8450_client_mask = BIT(PMIC_GLINK_CLIENT_BATT) |
380 							   BIT(PMIC_GLINK_CLIENT_ALTMODE) |
381 							   BIT(PMIC_GLINK_CLIENT_UCSI);
382 
383 static const struct of_device_id pmic_glink_of_match[] = {
384 	{ .compatible = "qcom,pmic-glink", .data = &pmic_glink_sm8450_client_mask },
385 	{}
386 };
387 MODULE_DEVICE_TABLE(of, pmic_glink_of_match);
388 
389 static struct platform_driver pmic_glink_driver = {
390 	.probe = pmic_glink_probe,
391 	.remove = pmic_glink_remove,
392 	.driver = {
393 		.name = "qcom_pmic_glink",
394 		.of_match_table = pmic_glink_of_match,
395 	},
396 };
397 
pmic_glink_init(void)398 static int pmic_glink_init(void)
399 {
400 	int ret;
401 
402 	ret = platform_driver_register(&pmic_glink_driver);
403 	if (ret < 0)
404 		return ret;
405 
406 	ret = register_rpmsg_driver(&pmic_glink_rpmsg_driver);
407 	if (ret < 0) {
408 		platform_driver_unregister(&pmic_glink_driver);
409 		return ret;
410 	}
411 
412 	return 0;
413 }
414 module_init(pmic_glink_init);
415 
pmic_glink_exit(void)416 static void pmic_glink_exit(void)
417 {
418 	unregister_rpmsg_driver(&pmic_glink_rpmsg_driver);
419 	platform_driver_unregister(&pmic_glink_driver);
420 }
421 module_exit(pmic_glink_exit);
422 
423 MODULE_DESCRIPTION("Qualcomm PMIC GLINK driver");
424 MODULE_LICENSE("GPL");
425