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v3.1
 1/*
 2 * i2c-boardinfo.c - collect pre-declarations of I2C devices
 3 *
 4 * This program is free software; you can redistribute it and/or modify
 5 * it under the terms of the GNU General Public License as published by
 6 * the Free Software Foundation; either version 2 of the License, or
 7 * (at your option) any later version.
 8 *
 9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17 */
18
19#include <linux/kernel.h>
20#include <linux/i2c.h>
21#include <linux/slab.h>
22#include <linux/rwsem.h>
 
23
24#include "i2c-core.h"
25
26
27/* These symbols are exported ONLY FOR the i2c core.
28 * No other users will be supported.
29 */
30DECLARE_RWSEM(__i2c_board_lock);
31EXPORT_SYMBOL_GPL(__i2c_board_lock);
32
33LIST_HEAD(__i2c_board_list);
34EXPORT_SYMBOL_GPL(__i2c_board_list);
35
36int __i2c_first_dynamic_bus_num;
37EXPORT_SYMBOL_GPL(__i2c_first_dynamic_bus_num);
38
39
40/**
41 * i2c_register_board_info - statically declare I2C devices
42 * @busnum: identifies the bus to which these devices belong
43 * @info: vector of i2c device descriptors
44 * @len: how many descriptors in the vector; may be zero to reserve
45 *	the specified bus number.
46 *
47 * Systems using the Linux I2C driver stack can declare tables of board info
48 * while they initialize.  This should be done in board-specific init code
49 * near arch_initcall() time, or equivalent, before any I2C adapter driver is
50 * registered.  For example, mainboard init code could define several devices,
51 * as could the init code for each daughtercard in a board stack.
52 *
53 * The I2C devices will be created later, after the adapter for the relevant
54 * bus has been registered.  After that moment, standard driver model tools
55 * are used to bind "new style" I2C drivers to the devices.  The bus number
56 * for any device declared using this routine is not available for dynamic
57 * allocation.
58 *
59 * The board info passed can safely be __initdata, but be careful of embedded
60 * pointers (for platform_data, functions, etc) since that won't be copied.
61 */
62int __init
63i2c_register_board_info(int busnum,
64	struct i2c_board_info const *info, unsigned len)
65{
66	int status;
67
68	down_write(&__i2c_board_lock);
69
70	/* dynamic bus numbers will be assigned after the last static one */
71	if (busnum >= __i2c_first_dynamic_bus_num)
72		__i2c_first_dynamic_bus_num = busnum + 1;
73
74	for (status = 0; len; len--, info++) {
75		struct i2c_devinfo	*devinfo;
76
77		devinfo = kzalloc(sizeof(*devinfo), GFP_KERNEL);
78		if (!devinfo) {
79			pr_debug("i2c-core: can't register boardinfo!\n");
80			status = -ENOMEM;
81			break;
82		}
83
84		devinfo->busnum = busnum;
85		devinfo->board_info = *info;
86		list_add_tail(&devinfo->list, &__i2c_board_list);
87	}
88
89	up_write(&__i2c_board_lock);
90
91	return status;
92}
v4.6
 1/*
 2 * i2c-boardinfo.c - collect pre-declarations of I2C devices
 3 *
 4 * This program is free software; you can redistribute it and/or modify
 5 * it under the terms of the GNU General Public License as published by
 6 * the Free Software Foundation; either version 2 of the License, or
 7 * (at your option) any later version.
 8 *
 9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 * GNU General Public License for more details.
 
 
 
 
13 */
14
15#include <linux/export.h>
16#include <linux/i2c.h>
17#include <linux/kernel.h>
18#include <linux/rwsem.h>
19#include <linux/slab.h>
20
21#include "i2c-core.h"
22
23
24/* These symbols are exported ONLY FOR the i2c core.
25 * No other users will be supported.
26 */
27DECLARE_RWSEM(__i2c_board_lock);
28EXPORT_SYMBOL_GPL(__i2c_board_lock);
29
30LIST_HEAD(__i2c_board_list);
31EXPORT_SYMBOL_GPL(__i2c_board_list);
32
33int __i2c_first_dynamic_bus_num;
34EXPORT_SYMBOL_GPL(__i2c_first_dynamic_bus_num);
35
36
37/**
38 * i2c_register_board_info - statically declare I2C devices
39 * @busnum: identifies the bus to which these devices belong
40 * @info: vector of i2c device descriptors
41 * @len: how many descriptors in the vector; may be zero to reserve
42 *	the specified bus number.
43 *
44 * Systems using the Linux I2C driver stack can declare tables of board info
45 * while they initialize.  This should be done in board-specific init code
46 * near arch_initcall() time, or equivalent, before any I2C adapter driver is
47 * registered.  For example, mainboard init code could define several devices,
48 * as could the init code for each daughtercard in a board stack.
49 *
50 * The I2C devices will be created later, after the adapter for the relevant
51 * bus has been registered.  After that moment, standard driver model tools
52 * are used to bind "new style" I2C drivers to the devices.  The bus number
53 * for any device declared using this routine is not available for dynamic
54 * allocation.
55 *
56 * The board info passed can safely be __initdata, but be careful of embedded
57 * pointers (for platform_data, functions, etc) since that won't be copied.
58 */
59int __init
60i2c_register_board_info(int busnum,
61	struct i2c_board_info const *info, unsigned len)
62{
63	int status;
64
65	down_write(&__i2c_board_lock);
66
67	/* dynamic bus numbers will be assigned after the last static one */
68	if (busnum >= __i2c_first_dynamic_bus_num)
69		__i2c_first_dynamic_bus_num = busnum + 1;
70
71	for (status = 0; len; len--, info++) {
72		struct i2c_devinfo	*devinfo;
73
74		devinfo = kzalloc(sizeof(*devinfo), GFP_KERNEL);
75		if (!devinfo) {
76			pr_debug("i2c-core: can't register boardinfo!\n");
77			status = -ENOMEM;
78			break;
79		}
80
81		devinfo->busnum = busnum;
82		devinfo->board_info = *info;
83		list_add_tail(&devinfo->list, &__i2c_board_list);
84	}
85
86	up_write(&__i2c_board_lock);
87
88	return status;
89}