1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  *  include/asm-ppc/pmac_low_i2c.h
4  *
5  *  Copyright (C) 2003 Ben. Herrenschmidt (benh@kernel.crashing.org)
6  */
7 #ifndef __PMAC_LOW_I2C_H__
8 #define __PMAC_LOW_I2C_H__
9 #ifdef __KERNEL__
10 
11 /* i2c mode (based on the platform functions format) */
12 enum {
13 	pmac_i2c_mode_dumb	= 1,
14 	pmac_i2c_mode_std	= 2,
15 	pmac_i2c_mode_stdsub	= 3,
16 	pmac_i2c_mode_combined	= 4,
17 };
18 
19 /* RW bit in address */
20 enum {
21 	pmac_i2c_read		= 0x01,
22 	pmac_i2c_write		= 0x00
23 };
24 
25 /* i2c bus type */
26 enum {
27 	pmac_i2c_bus_keywest	= 0,
28 	pmac_i2c_bus_pmu	= 1,
29 	pmac_i2c_bus_smu	= 2,
30 };
31 
32 /* i2c bus features */
33 enum {
34 	/* can_largesub : supports >1 byte subaddresses (SMU only) */
35 	pmac_i2c_can_largesub	= 0x00000001u,
36 
37 	/* multibus : device node holds multiple busses, bus number is
38 	 * encoded in bits 0xff00 of "reg" of a given device
39 	 */
40 	pmac_i2c_multibus	= 0x00000002u,
41 };
42 
43 /* i2c busses in the system */
44 struct pmac_i2c_bus;
45 struct i2c_adapter;
46 
47 /* Init, called early during boot */
48 extern int pmac_i2c_init(void);
49 
50 /* Lookup an i2c bus for a device-node. The node can be either the bus
51  * node itself or a device below it. In the case of a multibus, the bus
52  * node itself is the controller node, else, it's a child of the controller
53  * node
54  */
55 extern struct pmac_i2c_bus *pmac_i2c_find_bus(struct device_node *node);
56 
57 /* Get the address for an i2c device. This strips the bus number if
58  * necessary. The 7 bits address is returned 1 bit right shifted so that the
59  * direction can be directly ored in
60  */
61 extern u8 pmac_i2c_get_dev_addr(struct device_node *device);
62 
63 /* Get infos about a bus */
64 extern struct device_node *pmac_i2c_get_controller(struct pmac_i2c_bus *bus);
65 extern struct device_node *pmac_i2c_get_bus_node(struct pmac_i2c_bus *bus);
66 extern int pmac_i2c_get_type(struct pmac_i2c_bus *bus);
67 extern int pmac_i2c_get_flags(struct pmac_i2c_bus *bus);
68 extern int pmac_i2c_get_channel(struct pmac_i2c_bus *bus);
69 
70 /* i2c layer adapter helpers */
71 extern struct i2c_adapter *pmac_i2c_get_adapter(struct pmac_i2c_bus *bus);
72 extern struct pmac_i2c_bus *pmac_i2c_adapter_to_bus(struct i2c_adapter *adapter);
73 
74 /* March a device or bus with an i2c adapter structure, to be used by drivers
75  * to match device-tree nodes with i2c adapters during adapter discovery
76  * callbacks
77  */
78 extern int pmac_i2c_match_adapter(struct device_node *dev,
79 				  struct i2c_adapter *adapter);
80 
81 
82 /* (legacy) Locking functions exposed to i2c-keywest */
83 extern int pmac_low_i2c_lock(struct device_node *np);
84 extern int pmac_low_i2c_unlock(struct device_node *np);
85 
86 /* Access functions for platform code */
87 extern int pmac_i2c_open(struct pmac_i2c_bus *bus, int polled);
88 extern void pmac_i2c_close(struct pmac_i2c_bus *bus);
89 extern int pmac_i2c_setmode(struct pmac_i2c_bus *bus, int mode);
90 extern int pmac_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
91 			 u32 subaddr, u8 *data,  int len);
92 
93 /* Suspend/resume code called by via-pmu directly for now */
94 extern void pmac_pfunc_i2c_suspend(void);
95 extern void pmac_pfunc_i2c_resume(void);
96 
97 #endif /* __KERNEL__ */
98 #endif /* __PMAC_LOW_I2C_H__ */
99