linux_dsm_epyc7002/drivers/i2c/i2c-boardinfo.c
Dmitry Torokhov 4124c4eba4 i2c: allow attaching IRQ resources to i2c_board_info
Simple integer for interrupt number is not expressive enough, as it does
not convey interrupt trigger type that should be used. Let's allow
attaching array of resources to the board info and have i2c core parse
first IRQ resource and set up interrupt trigger as needed.

Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2017-04-01 09:36:19 -07:00

112 lines
3.3 KiB
C

/*
* i2c-boardinfo.c - collect pre-declarations of I2C devices
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/export.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/property.h>
#include <linux/rwsem.h>
#include <linux/slab.h>
#include "i2c-core.h"
/* These symbols are exported ONLY FOR the i2c core.
* No other users will be supported.
*/
DECLARE_RWSEM(__i2c_board_lock);
EXPORT_SYMBOL_GPL(__i2c_board_lock);
LIST_HEAD(__i2c_board_list);
EXPORT_SYMBOL_GPL(__i2c_board_list);
int __i2c_first_dynamic_bus_num;
EXPORT_SYMBOL_GPL(__i2c_first_dynamic_bus_num);
/**
* i2c_register_board_info - statically declare I2C devices
* @busnum: identifies the bus to which these devices belong
* @info: vector of i2c device descriptors
* @len: how many descriptors in the vector; may be zero to reserve
* the specified bus number.
*
* Systems using the Linux I2C driver stack can declare tables of board info
* while they initialize. This should be done in board-specific init code
* near arch_initcall() time, or equivalent, before any I2C adapter driver is
* registered. For example, mainboard init code could define several devices,
* as could the init code for each daughtercard in a board stack.
*
* The I2C devices will be created later, after the adapter for the relevant
* bus has been registered. After that moment, standard driver model tools
* are used to bind "new style" I2C drivers to the devices. The bus number
* for any device declared using this routine is not available for dynamic
* allocation.
*
* The board info passed can safely be __initdata, but be careful of embedded
* pointers (for platform_data, functions, etc) since that won't be copied.
* Device properties are deep-copied though.
*/
int i2c_register_board_info(int busnum, struct i2c_board_info const *info, unsigned len)
{
int status;
down_write(&__i2c_board_lock);
/* dynamic bus numbers will be assigned after the last static one */
if (busnum >= __i2c_first_dynamic_bus_num)
__i2c_first_dynamic_bus_num = busnum + 1;
for (status = 0; len; len--, info++) {
struct i2c_devinfo *devinfo;
devinfo = kzalloc(sizeof(*devinfo), GFP_KERNEL);
if (!devinfo) {
pr_debug("i2c-core: can't register boardinfo!\n");
status = -ENOMEM;
break;
}
devinfo->busnum = busnum;
devinfo->board_info = *info;
if (info->properties) {
devinfo->board_info.properties =
property_entries_dup(info->properties);
if (IS_ERR(devinfo->board_info.properties)) {
status = PTR_ERR(devinfo->board_info.properties);
break;
}
}
if (info->resources) {
devinfo->board_info.resources =
kmemdup(info->resources,
info->num_resources *
sizeof(*info->resources),
GFP_KERNEL);
if (!devinfo->board_info.resources) {
status = -ENOMEM;
break;
}
}
list_add_tail(&devinfo->list, &__i2c_board_list);
}
up_write(&__i2c_board_lock);
return status;
}