xref: /openbmc/linux/drivers/i3c/device.c (revision 2fa5ebe3)
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(const 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  * i3c_device_match_id() - Returns the i3c_device_id entry matching @i3cdev
213  * @i3cdev: I3C device
214  * @id_table: I3C device match table
215  *
216  * Return: a pointer to an i3c_device_id object or NULL if there's no match.
217  */
218 const struct i3c_device_id *
219 i3c_device_match_id(struct i3c_device *i3cdev,
220 		    const struct i3c_device_id *id_table)
221 {
222 	struct i3c_device_info devinfo;
223 	const struct i3c_device_id *id;
224 	u16 manuf, part, ext_info;
225 	bool rndpid;
226 
227 	i3c_device_get_info(i3cdev, &devinfo);
228 
229 	manuf = I3C_PID_MANUF_ID(devinfo.pid);
230 	part = I3C_PID_PART_ID(devinfo.pid);
231 	ext_info = I3C_PID_EXTRA_INFO(devinfo.pid);
232 	rndpid = I3C_PID_RND_LOWER_32BITS(devinfo.pid);
233 
234 	for (id = id_table; id->match_flags != 0; id++) {
235 		if ((id->match_flags & I3C_MATCH_DCR) &&
236 		    id->dcr != devinfo.dcr)
237 			continue;
238 
239 		if ((id->match_flags & I3C_MATCH_MANUF) &&
240 		    id->manuf_id != manuf)
241 			continue;
242 
243 		if ((id->match_flags & I3C_MATCH_PART) &&
244 		    (rndpid || id->part_id != part))
245 			continue;
246 
247 		if ((id->match_flags & I3C_MATCH_EXTRA_INFO) &&
248 		    (rndpid || id->extra_info != ext_info))
249 			continue;
250 
251 		return id;
252 	}
253 
254 	return NULL;
255 }
256 EXPORT_SYMBOL_GPL(i3c_device_match_id);
257 
258 /**
259  * i3c_driver_register_with_owner() - register an I3C device driver
260  *
261  * @drv: driver to register
262  * @owner: module that owns this driver
263  *
264  * Register @drv to the core.
265  *
266  * Return: 0 in case of success, a negative error core otherwise.
267  */
268 int i3c_driver_register_with_owner(struct i3c_driver *drv, struct module *owner)
269 {
270 	drv->driver.owner = owner;
271 	drv->driver.bus = &i3c_bus_type;
272 
273 	if (!drv->probe) {
274 		pr_err("Trying to register an i3c driver without probe callback\n");
275 		return -EINVAL;
276 	}
277 
278 	return driver_register(&drv->driver);
279 }
280 EXPORT_SYMBOL_GPL(i3c_driver_register_with_owner);
281 
282 /**
283  * i3c_driver_unregister() - unregister an I3C device driver
284  *
285  * @drv: driver to unregister
286  *
287  * Unregister @drv.
288  */
289 void i3c_driver_unregister(struct i3c_driver *drv)
290 {
291 	driver_unregister(&drv->driver);
292 }
293 EXPORT_SYMBOL_GPL(i3c_driver_unregister);
294