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