|  | /* | 
|  | * cros_ec_lpc_reg - LPC access to the Chrome OS Embedded Controller | 
|  | * | 
|  | * Copyright (C) 2016 Google, Inc | 
|  | * | 
|  | * This software is licensed under the terms of the GNU General Public | 
|  | * License version 2, as published by the Free Software Foundation, and | 
|  | * may be copied, distributed, and modified under those terms. | 
|  | * | 
|  | * 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. | 
|  | * | 
|  | * This driver uses the Chrome OS EC byte-level message-based protocol for | 
|  | * communicating the keyboard state (which keys are pressed) from a keyboard EC | 
|  | * to the AP over some bus (such as i2c, lpc, spi).  The EC does debouncing, | 
|  | * but everything else (including deghosting) is done here.  The main | 
|  | * motivation for this is to keep the EC firmware as simple as possible, since | 
|  | * it cannot be easily upgraded and EC flash/IRAM space is relatively | 
|  | * expensive. | 
|  | */ | 
|  |  | 
|  | #ifndef __LINUX_MFD_CROS_EC_REG_H | 
|  | #define __LINUX_MFD_CROS_EC_REG_H | 
|  |  | 
|  | /** | 
|  | * cros_ec_lpc_read_bytes - Read bytes from a given LPC-mapped address. | 
|  | * Returns 8-bit checksum of all bytes read. | 
|  | * | 
|  | * @offset: Base read address | 
|  | * @length: Number of bytes to read | 
|  | * @dest: Destination buffer | 
|  | */ | 
|  | u8 cros_ec_lpc_read_bytes(unsigned int offset, unsigned int length, u8 *dest); | 
|  |  | 
|  | /** | 
|  | * cros_ec_lpc_write_bytes - Write bytes to a given LPC-mapped address. | 
|  | * Returns 8-bit checksum of all bytes written. | 
|  | * | 
|  | * @offset: Base write address | 
|  | * @length: Number of bytes to write | 
|  | * @msg: Write data buffer | 
|  | */ | 
|  | u8 cros_ec_lpc_write_bytes(unsigned int offset, unsigned int length, u8 *msg); | 
|  |  | 
|  | /** | 
|  | * cros_ec_lpc_reg_init | 
|  | * | 
|  | * Initialize register I/O. | 
|  | */ | 
|  | void cros_ec_lpc_reg_init(void); | 
|  |  | 
|  | /** | 
|  | * cros_ec_lpc_reg_destroy | 
|  | * | 
|  | * Cleanup reg I/O. | 
|  | */ | 
|  | void cros_ec_lpc_reg_destroy(void); | 
|  |  | 
|  | #endif /* __LINUX_MFD_CROS_EC_REG_H */ |