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
drv_to_i3cdrv(struct device_driver * drv)186 static inline struct i3c_driver *drv_to_i3cdrv(struct device_driver *drv)
187 {
188 return container_of(drv, struct i3c_driver, driver);
189 }
190
191 struct device *i3cdev_to_dev(struct i3c_device *i3cdev);
192
193 /**
194 * dev_to_i3cdev() - Returns the I3C device containing @dev
195 * @__dev: device object
196 *
197 * Return: a pointer to an I3C device object.
198 */
199 #define dev_to_i3cdev(__dev) container_of_const(__dev, struct i3c_device, dev)
200
201 const struct i3c_device_id *
202 i3c_device_match_id(struct i3c_device *i3cdev,
203 const struct i3c_device_id *id_table);
204
i3cdev_set_drvdata(struct i3c_device * i3cdev,void * data)205 static inline void i3cdev_set_drvdata(struct i3c_device *i3cdev,
206 void *data)
207 {
208 struct device *dev = i3cdev_to_dev(i3cdev);
209
210 dev_set_drvdata(dev, data);
211 }
212
i3cdev_get_drvdata(struct i3c_device * i3cdev)213 static inline void *i3cdev_get_drvdata(struct i3c_device *i3cdev)
214 {
215 struct device *dev = i3cdev_to_dev(i3cdev);
216
217 return dev_get_drvdata(dev);
218 }
219
220 int i3c_driver_register_with_owner(struct i3c_driver *drv,
221 struct module *owner);
222 void i3c_driver_unregister(struct i3c_driver *drv);
223
224 #define i3c_driver_register(__drv) \
225 i3c_driver_register_with_owner(__drv, THIS_MODULE)
226
227 /**
228 * module_i3c_driver() - Register a module providing an I3C driver
229 * @__drv: the I3C driver to register
230 *
231 * Provide generic init/exit functions that simply register/unregister an I3C
232 * driver.
233 * Should be used by any driver that does not require extra init/cleanup steps.
234 */
235 #define module_i3c_driver(__drv) \
236 module_driver(__drv, i3c_driver_register, i3c_driver_unregister)
237
238 /**
239 * i3c_i2c_driver_register() - Register an i2c and an i3c driver
240 * @i3cdrv: the I3C driver to register
241 * @i2cdrv: the I2C driver to register
242 *
243 * This function registers both @i2cdev and @i3cdev, and fails if one of these
244 * registrations fails. This is mainly useful for devices that support both I2C
245 * and I3C modes.
246 * Note that when CONFIG_I3C is not enabled, this function only registers the
247 * I2C driver.
248 *
249 * Return: 0 if both registrations succeeds, a negative error code otherwise.
250 */
i3c_i2c_driver_register(struct i3c_driver * i3cdrv,struct i2c_driver * i2cdrv)251 static inline int i3c_i2c_driver_register(struct i3c_driver *i3cdrv,
252 struct i2c_driver *i2cdrv)
253 {
254 int ret;
255
256 ret = i2c_add_driver(i2cdrv);
257 if (ret || !IS_ENABLED(CONFIG_I3C))
258 return ret;
259
260 ret = i3c_driver_register(i3cdrv);
261 if (ret)
262 i2c_del_driver(i2cdrv);
263
264 return ret;
265 }
266
267 /**
268 * i3c_i2c_driver_unregister() - Unregister an i2c and an i3c driver
269 * @i3cdrv: the I3C driver to register
270 * @i2cdrv: the I2C driver to register
271 *
272 * This function unregisters both @i3cdrv and @i2cdrv.
273 * Note that when CONFIG_I3C is not enabled, this function only unregisters the
274 * @i2cdrv.
275 */
i3c_i2c_driver_unregister(struct i3c_driver * i3cdrv,struct i2c_driver * i2cdrv)276 static inline void i3c_i2c_driver_unregister(struct i3c_driver *i3cdrv,
277 struct i2c_driver *i2cdrv)
278 {
279 if (IS_ENABLED(CONFIG_I3C))
280 i3c_driver_unregister(i3cdrv);
281
282 i2c_del_driver(i2cdrv);
283 }
284
285 /**
286 * module_i3c_i2c_driver() - Register a module providing an I3C and an I2C
287 * driver
288 * @__i3cdrv: the I3C driver to register
289 * @__i2cdrv: the I3C driver to register
290 *
291 * Provide generic init/exit functions that simply register/unregister an I3C
292 * and an I2C driver.
293 * This macro can be used even if CONFIG_I3C is disabled, in this case, only
294 * the I2C driver will be registered.
295 * Should be used by any driver that does not require extra init/cleanup steps.
296 */
297 #define module_i3c_i2c_driver(__i3cdrv, __i2cdrv) \
298 module_driver(__i3cdrv, \
299 i3c_i2c_driver_register, \
300 i3c_i2c_driver_unregister, \
301 __i2cdrv)
302
303 int i3c_device_do_priv_xfers(struct i3c_device *dev,
304 struct i3c_priv_xfer *xfers,
305 int nxfers);
306
307 int i3c_device_do_setdasa(struct i3c_device *dev);
308
309 void i3c_device_get_info(const struct i3c_device *dev, struct i3c_device_info *info);
310
311 struct i3c_ibi_payload {
312 unsigned int len;
313 const void *data;
314 };
315
316 /**
317 * struct i3c_ibi_setup - IBI setup object
318 * @max_payload_len: maximum length of the payload associated to an IBI. If one
319 * IBI appears to have a payload that is bigger than this
320 * number, the IBI will be rejected.
321 * @num_slots: number of pre-allocated IBI slots. This should be chosen so that
322 * the system never runs out of IBI slots, otherwise you'll lose
323 * IBIs.
324 * @handler: IBI handler, every time an IBI is received. This handler is called
325 * in a workqueue context. It is allowed to sleep and send new
326 * messages on the bus, though it's recommended to keep the
327 * processing done there as fast as possible to avoid delaying
328 * processing of other queued on the same workqueue.
329 *
330 * Temporary structure used to pass information to i3c_device_request_ibi().
331 * This object can be allocated on the stack since i3c_device_request_ibi()
332 * copies every bit of information and do not use it after
333 * i3c_device_request_ibi() has returned.
334 */
335 struct i3c_ibi_setup {
336 unsigned int max_payload_len;
337 unsigned int num_slots;
338 void (*handler)(struct i3c_device *dev,
339 const struct i3c_ibi_payload *payload);
340 };
341
342 int i3c_device_request_ibi(struct i3c_device *dev,
343 const struct i3c_ibi_setup *setup);
344 void i3c_device_free_ibi(struct i3c_device *dev);
345 int i3c_device_enable_ibi(struct i3c_device *dev);
346 int i3c_device_disable_ibi(struct i3c_device *dev);
347
348 #endif /* I3C_DEV_H */
349