/* * i2c-boardinfo.h - 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. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include <linux/kernel.h> #include <linux/i2c.h> #include "i2c-core.h" /* These symbols are exported ONLY FOR the i2c core. * No other users will be supported. */ DEFINE_MUTEX(__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. */ int __init i2c_register_board_info(int busnum, struct i2c_board_info const *info, unsigned len) { int status; mutex_lock(&__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; list_add_tail(&devinfo->list, &__i2c_board_list); } mutex_unlock(&__i2c_board_lock); return status; }