xref: /openbmc/linux/drivers/i3c/device.c (revision e8254a8e)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2018 Cadence Design Systems Inc.
4  *
5  * Author: Boris Brezillon <boris.brezillon@bootlin.com>
6  */
7 
8 #include <linux/atomic.h>
9 #include <linux/bug.h>
10 #include <linux/completion.h>
11 #include <linux/device.h>
12 #include <linux/mutex.h>
13 #include <linux/slab.h>
14 
15 #include "internals.h"
16 
17 /**
18  * i3c_device_do_priv_xfers() - do I3C SDR private transfers directed to a
19  *				specific device
20  *
21  * @dev: device with which the transfers should be done
22  * @xfers: array of transfers
23  * @nxfers: number of transfers
24  *
25  * Initiate one or several private SDR transfers with @dev.
26  *
27  * This function can sleep and thus cannot be called in atomic context.
28  *
29  * Return: 0 in case of success, a negative error core otherwise.
30  */
31 int i3c_device_do_priv_xfers(struct i3c_device *dev,
32 			     struct i3c_priv_xfer *xfers,
33 			     int nxfers)
34 {
35 	int ret, i;
36 
37 	if (nxfers < 1)
38 		return 0;
39 
40 	for (i = 0; i < nxfers; i++) {
41 		if (!xfers[i].len || !xfers[i].data.in)
42 			return -EINVAL;
43 	}
44 
45 	i3c_bus_normaluse_lock(dev->bus);
46 	ret = i3c_dev_do_priv_xfers_locked(dev->desc, xfers, nxfers);
47 	i3c_bus_normaluse_unlock(dev->bus);
48 
49 	return ret;
50 }
51 EXPORT_SYMBOL_GPL(i3c_device_do_priv_xfers);
52 
53 /**
54  * i3c_device_do_setdasa() - do I3C dynamic address assignement with
55  *                           static address
56  *
57  * @dev: device with which the DAA should be done
58  *
59  * Return: 0 in case of success, a negative error core otherwise.
60  */
61 int i3c_device_do_setdasa(struct i3c_device *dev)
62 {
63 	int ret;
64 
65 	i3c_bus_normaluse_lock(dev->bus);
66 	ret = i3c_dev_setdasa_locked(dev->desc);
67 	i3c_bus_normaluse_unlock(dev->bus);
68 
69 	return ret;
70 }
71 EXPORT_SYMBOL_GPL(i3c_device_do_setdasa);
72 
73 /**
74  * i3c_device_get_info() - get I3C device information
75  *
76  * @dev: device we want information on
77  * @info: the information object to fill in
78  *
79  * Retrieve I3C dev info.
80  */
81 void i3c_device_get_info(struct i3c_device *dev,
82 			 struct i3c_device_info *info)
83 {
84 	if (!info)
85 		return;
86 
87 	i3c_bus_normaluse_lock(dev->bus);
88 	if (dev->desc)
89 		*info = dev->desc->info;
90 	i3c_bus_normaluse_unlock(dev->bus);
91 }
92 EXPORT_SYMBOL_GPL(i3c_device_get_info);
93 
94 /**
95  * i3c_device_disable_ibi() - Disable IBIs coming from a specific device
96  * @dev: device on which IBIs should be disabled
97  *
98  * This function disable IBIs coming from a specific device and wait for
99  * all pending IBIs to be processed.
100  *
101  * Return: 0 in case of success, a negative error core otherwise.
102  */
103 int i3c_device_disable_ibi(struct i3c_device *dev)
104 {
105 	int ret = -ENOENT;
106 
107 	i3c_bus_normaluse_lock(dev->bus);
108 	if (dev->desc) {
109 		mutex_lock(&dev->desc->ibi_lock);
110 		ret = i3c_dev_disable_ibi_locked(dev->desc);
111 		mutex_unlock(&dev->desc->ibi_lock);
112 	}
113 	i3c_bus_normaluse_unlock(dev->bus);
114 
115 	return ret;
116 }
117 EXPORT_SYMBOL_GPL(i3c_device_disable_ibi);
118 
119 /**
120  * i3c_device_enable_ibi() - Enable IBIs coming from a specific device
121  * @dev: device on which IBIs should be enabled
122  *
123  * This function enable IBIs coming from a specific device and wait for
124  * all pending IBIs to be processed. This should be called on a device
125  * where i3c_device_request_ibi() has succeeded.
126  *
127  * Note that IBIs from this device might be received before this function
128  * returns to its caller.
129  *
130  * Return: 0 in case of success, a negative error core otherwise.
131  */
132 int i3c_device_enable_ibi(struct i3c_device *dev)
133 {
134 	int ret = -ENOENT;
135 
136 	i3c_bus_normaluse_lock(dev->bus);
137 	if (dev->desc) {
138 		mutex_lock(&dev->desc->ibi_lock);
139 		ret = i3c_dev_enable_ibi_locked(dev->desc);
140 		mutex_unlock(&dev->desc->ibi_lock);
141 	}
142 	i3c_bus_normaluse_unlock(dev->bus);
143 
144 	return ret;
145 }
146 EXPORT_SYMBOL_GPL(i3c_device_enable_ibi);
147 
148 /**
149  * i3c_device_request_ibi() - Request an IBI
150  * @dev: device for which we should enable IBIs
151  * @req: setup requested for this IBI
152  *
153  * This function is responsible for pre-allocating all resources needed to
154  * process IBIs coming from @dev. When this function returns, the IBI is not
155  * enabled until i3c_device_enable_ibi() is called.
156  *
157  * Return: 0 in case of success, a negative error core otherwise.
158  */
159 int i3c_device_request_ibi(struct i3c_device *dev,
160 			   const struct i3c_ibi_setup *req)
161 {
162 	int ret = -ENOENT;
163 
164 	if (!req->handler || !req->num_slots)
165 		return -EINVAL;
166 
167 	i3c_bus_normaluse_lock(dev->bus);
168 	if (dev->desc) {
169 		mutex_lock(&dev->desc->ibi_lock);
170 		ret = i3c_dev_request_ibi_locked(dev->desc, req);
171 		mutex_unlock(&dev->desc->ibi_lock);
172 	}
173 	i3c_bus_normaluse_unlock(dev->bus);
174 
175 	return ret;
176 }
177 EXPORT_SYMBOL_GPL(i3c_device_request_ibi);
178 
179 /**
180  * i3c_device_free_ibi() - Free all resources needed for IBI handling
181  * @dev: device on which you want to release IBI resources
182  *
183  * This function is responsible for de-allocating resources previously
184  * allocated by i3c_device_request_ibi(). It should be called after disabling
185  * IBIs with i3c_device_disable_ibi().
186  */
187 void i3c_device_free_ibi(struct i3c_device *dev)
188 {
189 	i3c_bus_normaluse_lock(dev->bus);
190 	if (dev->desc) {
191 		mutex_lock(&dev->desc->ibi_lock);
192 		i3c_dev_free_ibi_locked(dev->desc);
193 		mutex_unlock(&dev->desc->ibi_lock);
194 	}
195 	i3c_bus_normaluse_unlock(dev->bus);
196 }
197 EXPORT_SYMBOL_GPL(i3c_device_free_ibi);
198 
199 /**
200  * i3cdev_to_dev() - Returns the device embedded in @i3cdev
201  * @i3cdev: I3C device
202  *
203  * Return: a pointer to a device object.
204  */
205 struct device *i3cdev_to_dev(struct i3c_device *i3cdev)
206 {
207 	return &i3cdev->dev;
208 }
209 EXPORT_SYMBOL_GPL(i3cdev_to_dev);
210 
211 /**
212  * dev_to_i3cdev() - Returns the I3C device containing @dev
213  * @dev: device object
214  *
215  * Return: a pointer to an I3C device object.
216  */
217 struct i3c_device *dev_to_i3cdev(struct device *dev)
218 {
219 	return container_of(dev, struct i3c_device, dev);
220 }
221 EXPORT_SYMBOL_GPL(dev_to_i3cdev);
222 
223 /**
224  * i3c_device_match_id() - Returns the i3c_device_id entry matching @i3cdev
225  * @i3cdev: I3C device
226  * @id_table: I3C device match table
227  *
228  * Return: a pointer to an i3c_device_id object or NULL if there's no match.
229  */
230 const struct i3c_device_id *
231 i3c_device_match_id(struct i3c_device *i3cdev,
232 		    const struct i3c_device_id *id_table)
233 {
234 	struct i3c_device_info devinfo;
235 	const struct i3c_device_id *id;
236 	u16 manuf, part, ext_info;
237 	bool rndpid;
238 
239 	i3c_device_get_info(i3cdev, &devinfo);
240 
241 	manuf = I3C_PID_MANUF_ID(devinfo.pid);
242 	part = I3C_PID_PART_ID(devinfo.pid);
243 	ext_info = I3C_PID_EXTRA_INFO(devinfo.pid);
244 	rndpid = I3C_PID_RND_LOWER_32BITS(devinfo.pid);
245 
246 	for (id = id_table; id->match_flags != 0; id++) {
247 		if ((id->match_flags & I3C_MATCH_DCR) &&
248 		    id->dcr != devinfo.dcr)
249 			continue;
250 
251 		if ((id->match_flags & I3C_MATCH_MANUF) &&
252 		    id->manuf_id != manuf)
253 			continue;
254 
255 		if ((id->match_flags & I3C_MATCH_PART) &&
256 		    (rndpid || id->part_id != part))
257 			continue;
258 
259 		if ((id->match_flags & I3C_MATCH_EXTRA_INFO) &&
260 		    (rndpid || id->extra_info != ext_info))
261 			continue;
262 
263 		return id;
264 	}
265 
266 	return NULL;
267 }
268 EXPORT_SYMBOL_GPL(i3c_device_match_id);
269 
270 /**
271  * i3c_driver_register_with_owner() - register an I3C device driver
272  *
273  * @drv: driver to register
274  * @owner: module that owns this driver
275  *
276  * Register @drv to the core.
277  *
278  * Return: 0 in case of success, a negative error core otherwise.
279  */
280 int i3c_driver_register_with_owner(struct i3c_driver *drv, struct module *owner)
281 {
282 	drv->driver.owner = owner;
283 	drv->driver.bus = &i3c_bus_type;
284 
285 	if (!drv->probe) {
286 		pr_err("Trying to register an i3c driver without probe callback\n");
287 		return -EINVAL;
288 	}
289 
290 	return driver_register(&drv->driver);
291 }
292 EXPORT_SYMBOL_GPL(i3c_driver_register_with_owner);
293 
294 /**
295  * i3c_driver_unregister() - unregister an I3C device driver
296  *
297  * @drv: driver to unregister
298  *
299  * Unregister @drv.
300  */
301 void i3c_driver_unregister(struct i3c_driver *drv)
302 {
303 	driver_unregister(&drv->driver);
304 }
305 EXPORT_SYMBOL_GPL(i3c_driver_unregister);
306