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 #ifndef I3C_DEV_H
9 #define I3C_DEV_H
10
11 #include <linux/bitops.h>
12 #include <linux/device.h>
13 #include <linux/i2c.h>
14 #include <linux/kconfig.h>
15 #include <linux/mod_devicetable.h>
16 #include <linux/module.h>
17
18 /**
19 * enum i3c_error_code - I3C error codes
20 *
21 * @I3C_ERROR_UNKNOWN: unknown error, usually means the error is not I3C
22 * related
23 * @I3C_ERROR_M0: M0 error
24 * @I3C_ERROR_M1: M1 error
25 * @I3C_ERROR_M2: M2 error
26 *
27 * These are the standard error codes as defined by the I3C specification.
28 * When -EIO is returned by the i3c_device_do_priv_xfers() or
29 * i3c_device_send_hdr_cmds() one can check the error code in
30 * &struct_i3c_priv_xfer.err or &struct i3c_hdr_cmd.err to get a better idea of
31 * what went wrong.
32 *
33 */
34 enum i3c_error_code {
35 I3C_ERROR_UNKNOWN = 0,
36 I3C_ERROR_M0 = 1,
37 I3C_ERROR_M1,
38 I3C_ERROR_M2,
39 };
40
41 /**
42 * enum i3c_hdr_mode - HDR mode ids
43 * @I3C_HDR_DDR: DDR mode
44 * @I3C_HDR_TSP: TSP mode
45 * @I3C_HDR_TSL: TSL mode
46 */
47 enum i3c_hdr_mode {
48 I3C_HDR_DDR,
49 I3C_HDR_TSP,
50 I3C_HDR_TSL,
51 };
52
53 /**
54 * struct i3c_priv_xfer - I3C SDR private transfer
55 * @rnw: encodes the transfer direction. true for a read, false for a write
56 * @len: transfer length in bytes of the transfer
57 * @actual_len: actual length in bytes are transferred by the controller
58 * @data: input/output buffer
59 * @data.in: input buffer. Must point to a DMA-able buffer
60 * @data.out: output buffer. Must point to a DMA-able buffer
61 * @err: I3C error code
62 */
63 struct i3c_priv_xfer {
64 u8 rnw;
65 u16 len;
66 u16 actual_len;
67 union {
68 void *in;
69 const void *out;
70 } data;
71 enum i3c_error_code err;
72 };
73
74 /**
75 * enum i3c_dcr - I3C DCR values
76 * @I3C_DCR_GENERIC_DEVICE: generic I3C device
77 */
78 enum i3c_dcr {
79 I3C_DCR_GENERIC_DEVICE = 0,
80 };
81
82 #define I3C_PID_MANUF_ID(pid) (((pid) & GENMASK_ULL(47, 33)) >> 33)
83 #define I3C_PID_RND_LOWER_32BITS(pid) (!!((pid) & BIT_ULL(32)))
84 #define I3C_PID_RND_VAL(pid) ((pid) & GENMASK_ULL(31, 0))
85 #define I3C_PID_PART_ID(pid) (((pid) & GENMASK_ULL(31, 16)) >> 16)
86 #define I3C_PID_INSTANCE_ID(pid) (((pid) & GENMASK_ULL(15, 12)) >> 12)
87 #define I3C_PID_EXTRA_INFO(pid) ((pid) & GENMASK_ULL(11, 0))
88
89 #define I3C_BCR_DEVICE_ROLE(bcr) ((bcr) & GENMASK(7, 6))
90 #define I3C_BCR_I3C_SLAVE (0 << 6)
91 #define I3C_BCR_I3C_MASTER (1 << 6)
92 #define I3C_BCR_HDR_CAP BIT(5)
93 #define I3C_BCR_BRIDGE BIT(4)
94 #define I3C_BCR_OFFLINE_CAP BIT(3)
95 #define I3C_BCR_IBI_PAYLOAD BIT(2)
96 #define I3C_BCR_IBI_REQ_CAP BIT(1)
97 #define I3C_BCR_MAX_DATA_SPEED_LIM BIT(0)
98
99 /**
100 * struct i3c_device_info - I3C device information
101 * @pid: Provisioned ID
102 * @bcr: Bus Characteristic Register
103 * @dcr: Device Characteristic Register
104 * @static_addr: static/I2C address
105 * @dyn_addr: dynamic address
106 * @hdr_cap: supported HDR modes
107 * @max_read_ds: max read speed information
108 * @max_write_ds: max write speed information
109 * @max_ibi_len: max IBI payload length
110 * @max_read_turnaround: max read turn-around time in micro-seconds
111 * @max_read_len: max private SDR read length in bytes
112 * @max_write_len: max private SDR write length in bytes
113 *
114 * These are all basic information that should be advertised by an I3C device.
115 * Some of them are optional depending on the device type and device
116 * capabilities.
117 * For each I3C slave attached to a master with
118 * i3c_master_add_i3c_dev_locked(), the core will send the relevant CCC command
119 * to retrieve these data.
120 */
121 struct i3c_device_info {
122 u64 pid;
123 u8 bcr;
124 u8 dcr;
125 u8 static_addr;
126 u8 dyn_addr;
127 u8 hdr_cap;
128 u8 max_read_ds;
129 u8 max_write_ds;
130 u8 max_ibi_len;
131 u32 max_read_turnaround;
132 u16 max_read_len;
133 u16 max_write_len;
134 };
135
136 /*
137 * I3C device internals are kept hidden from I3C device users. It's just
138 * simpler to refactor things when everything goes through getter/setters, and
139 * I3C device drivers should not have to worry about internal representation
140 * anyway.
141 */
142 struct i3c_device;
143
144 /* These macros should be used to i3c_device_id entries. */
145 #define I3C_MATCH_MANUF_AND_PART (I3C_MATCH_MANUF | I3C_MATCH_PART)
146
147 #define I3C_DEVICE(_manufid, _partid, _drvdata) \
148 { \
149 .match_flags = I3C_MATCH_MANUF_AND_PART, \
150 .manuf_id = _manufid, \
151 .part_id = _partid, \
152 .data = _drvdata, \
153 }
154
155 #define I3C_DEVICE_EXTRA_INFO(_manufid, _partid, _info, _drvdata) \
156 { \
157 .match_flags = I3C_MATCH_MANUF_AND_PART | \
158 I3C_MATCH_EXTRA_INFO, \
159 .manuf_id = _manufid, \
160 .part_id = _partid, \
161 .extra_info = _info, \
162 .data = _drvdata, \
163 }
164
165 #define I3C_CLASS(_dcr, _drvdata) \
166 { \
167 .match_flags = I3C_MATCH_DCR, \
168 .dcr = _dcr, \
169 }
170
171 /**
172 * struct i3c_driver - I3C device driver
173 * @driver: inherit from device_driver
174 * @probe: I3C device probe method
175 * @remove: I3C device remove method
176 * @id_table: I3C device match table. Will be used by the framework to decide
177 * which device to bind to this driver
178 */
179 struct i3c_driver {
180 struct device_driver driver;
181 int (*probe)(struct i3c_device *dev);
182 void (*remove)(struct i3c_device *dev);
183 const struct i3c_device_id *id_table;
184 };
185
186 #define drv_to_i3cdrv(__drv) container_of_const(__drv, struct i3c_driver, driver)
187
188 struct device *i3cdev_to_dev(struct i3c_device *i3cdev);
189
190 /**
191 * dev_to_i3cdev() - Returns the I3C device containing @dev
192 * @__dev: device object
193 *
194 * Return: a pointer to an I3C device object.
195 */
196 #define dev_to_i3cdev(__dev) container_of_const(__dev, struct i3c_device, dev)
197
198 const struct i3c_device_id *
199 i3c_device_match_id(struct i3c_device *i3cdev,
200 const struct i3c_device_id *id_table);
201
202 static inline void i3cdev_set_drvdata(struct i3c_device *i3cdev,
203 void *data)
204 {
205 struct device *dev = i3cdev_to_dev(i3cdev);
206
207 dev_set_drvdata(dev, data);
208 }
209
210 static inline void *i3cdev_get_drvdata(struct i3c_device *i3cdev)
211 {
212 struct device *dev = i3cdev_to_dev(i3cdev);
213
214 return dev_get_drvdata(dev);
215 }
216
217 int i3c_driver_register_with_owner(struct i3c_driver *drv,
218 struct module *owner);
219 void i3c_driver_unregister(struct i3c_driver *drv);
220
221 #define i3c_driver_register(__drv) \
222 i3c_driver_register_with_owner(__drv, THIS_MODULE)
223
224 /**
225 * module_i3c_driver() - Register a module providing an I3C driver
226 * @__drv: the I3C driver to register
227 *
228 * Provide generic init/exit functions that simply register/unregister an I3C
229 * driver.
230 * Should be used by any driver that does not require extra init/cleanup steps.
231 */
232 #define module_i3c_driver(__drv) \
233 module_driver(__drv, i3c_driver_register, i3c_driver_unregister)
234
235 /**
236 * i3c_i2c_driver_register() - Register an i2c and an i3c driver
237 * @i3cdrv: the I3C driver to register
238 * @i2cdrv: the I2C driver to register
239 *
240 * This function registers both @i2cdev and @i3cdev, and fails if one of these
241 * registrations fails. This is mainly useful for devices that support both I2C
242 * and I3C modes.
243 * Note that when CONFIG_I3C is not enabled, this function only registers the
244 * I2C driver.
245 *
246 * Return: 0 if both registrations succeeds, a negative error code otherwise.
247 */
248 static inline int i3c_i2c_driver_register(struct i3c_driver *i3cdrv,
249 struct i2c_driver *i2cdrv)
250 {
251 int ret;
252
253 ret = i2c_add_driver(i2cdrv);
254 if (ret || !IS_ENABLED(CONFIG_I3C))
255 return ret;
256
257 ret = i3c_driver_register(i3cdrv);
258 if (ret)
259 i2c_del_driver(i2cdrv);
260
261 return ret;
262 }
263
264 /**
265 * i3c_i2c_driver_unregister() - Unregister an i2c and an i3c driver
266 * @i3cdrv: the I3C driver to register
267 * @i2cdrv: the I2C driver to register
268 *
269 * This function unregisters both @i3cdrv and @i2cdrv.
270 * Note that when CONFIG_I3C is not enabled, this function only unregisters the
271 * @i2cdrv.
272 */
273 static inline void i3c_i2c_driver_unregister(struct i3c_driver *i3cdrv,
274 struct i2c_driver *i2cdrv)
275 {
276 if (IS_ENABLED(CONFIG_I3C))
277 i3c_driver_unregister(i3cdrv);
278
279 i2c_del_driver(i2cdrv);
280 }
281
282 /**
283 * module_i3c_i2c_driver() - Register a module providing an I3C and an I2C
284 * driver
285 * @__i3cdrv: the I3C driver to register
286 * @__i2cdrv: the I3C driver to register
287 *
288 * Provide generic init/exit functions that simply register/unregister an I3C
289 * and an I2C driver.
290 * This macro can be used even if CONFIG_I3C is disabled, in this case, only
291 * the I2C driver will be registered.
292 * Should be used by any driver that does not require extra init/cleanup steps.
293 */
294 #define module_i3c_i2c_driver(__i3cdrv, __i2cdrv) \
295 module_driver(__i3cdrv, \
296 i3c_i2c_driver_register, \
297 i3c_i2c_driver_unregister, \
298 __i2cdrv)
299
300 int i3c_device_do_priv_xfers(struct i3c_device *dev,
301 struct i3c_priv_xfer *xfers,
302 int nxfers);
303
304 int i3c_device_do_setdasa(struct i3c_device *dev);
305
306 void i3c_device_get_info(const struct i3c_device *dev, struct i3c_device_info *info);
307
308 struct i3c_ibi_payload {
309 unsigned int len;
310 const void *data;
311 };
312
313 /**
314 * struct i3c_ibi_setup - IBI setup object
315 * @max_payload_len: maximum length of the payload associated to an IBI. If one
316 * IBI appears to have a payload that is bigger than this
317 * number, the IBI will be rejected.
318 * @num_slots: number of pre-allocated IBI slots. This should be chosen so that
319 * the system never runs out of IBI slots, otherwise you'll lose
320 * IBIs.
321 * @handler: IBI handler, every time an IBI is received. This handler is called
322 * in a workqueue context. It is allowed to sleep and send new
323 * messages on the bus, though it's recommended to keep the
324 * processing done there as fast as possible to avoid delaying
325 * processing of other queued on the same workqueue.
326 *
327 * Temporary structure used to pass information to i3c_device_request_ibi().
328 * This object can be allocated on the stack since i3c_device_request_ibi()
329 * copies every bit of information and do not use it after
330 * i3c_device_request_ibi() has returned.
331 */
332 struct i3c_ibi_setup {
333 unsigned int max_payload_len;
334 unsigned int num_slots;
335 void (*handler)(struct i3c_device *dev,
336 const struct i3c_ibi_payload *payload);
337 };
338
339 int i3c_device_request_ibi(struct i3c_device *dev,
340 const struct i3c_ibi_setup *setup);
341 void i3c_device_free_ibi(struct i3c_device *dev);
342 int i3c_device_enable_ibi(struct i3c_device *dev);
343 int i3c_device_disable_ibi(struct i3c_device *dev);
344
345 #endif /* I3C_DEV_H */
346
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