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 */
34enum 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 */
47enum 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 */
63struct 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 */
78enum 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 */
121struct 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 */
142struct 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 */
179struct 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
186static inline struct i3c_driver *drv_to_i3cdrv(struct device_driver *drv)
187{
188	return container_of(drv, struct i3c_driver, driver);
189}
190
191struct 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
201const struct i3c_device_id *
202i3c_device_match_id(struct i3c_device *i3cdev,
203		    const struct i3c_device_id *id_table);
204
205static 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
213static 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
220int i3c_driver_register_with_owner(struct i3c_driver *drv,
221				   struct module *owner);
222void 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 */
251static 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 */
276static 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
303int i3c_device_do_priv_xfers(struct i3c_device *dev,
304			     struct i3c_priv_xfer *xfers,
305			     int nxfers);
306
307int i3c_device_do_setdasa(struct i3c_device *dev);
308
309void i3c_device_get_info(const struct i3c_device *dev, struct i3c_device_info *info);
310
311struct 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 */
335struct 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
342int i3c_device_request_ibi(struct i3c_device *dev,
343			   const struct i3c_ibi_setup *setup);
344void i3c_device_free_ibi(struct i3c_device *dev);
345int i3c_device_enable_ibi(struct i3c_device *dev);
346int i3c_device_disable_ibi(struct i3c_device *dev);
347
348#endif /* I3C_DEV_H */
349