linux/drivers/platform/chrome/cros_ec_lpc_reg.c

102 lines
2.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
// LPC interface for ChromeOS Embedded Controller
//
// Copyright (C) 2016 Google, Inc
#include <linux/io.h>
#include <linux/mfd/cros_ec.h>
#include <linux/mfd/cros_ec_commands.h>
#include "cros_ec_lpc_mec.h"
static u8 lpc_read_bytes(unsigned int offset, unsigned int length, u8 *dest)
{
int i;
int sum = 0;
for (i = 0; i < length; ++i) {
dest[i] = inb(offset + i);
sum += dest[i];
}
/* Return checksum of all bytes read */
return sum;
}
static u8 lpc_write_bytes(unsigned int offset, unsigned int length, u8 *msg)
{
int i;
int sum = 0;
for (i = 0; i < length; ++i) {
outb(msg[i], offset + i);
sum += msg[i];
}
/* Return checksum of all bytes written */
return sum;
}
#ifdef CONFIG_CROS_EC_LPC_MEC
u8 cros_ec_lpc_read_bytes(unsigned int offset, unsigned int length, u8 *dest)
{
int in_range = cros_ec_lpc_mec_in_range(offset, length);
if (in_range < 0)
return 0;
return in_range ?
cros_ec_lpc_io_bytes_mec(MEC_IO_READ,
offset - EC_HOST_CMD_REGION0,
length, dest) :
lpc_read_bytes(offset, length, dest);
}
u8 cros_ec_lpc_write_bytes(unsigned int offset, unsigned int length, u8 *msg)
{
int in_range = cros_ec_lpc_mec_in_range(offset, length);
if (in_range < 0)
return 0;
return in_range ?
cros_ec_lpc_io_bytes_mec(MEC_IO_WRITE,
offset - EC_HOST_CMD_REGION0,
length, msg) :
lpc_write_bytes(offset, length, msg);
}
void cros_ec_lpc_reg_init(void)
{
cros_ec_lpc_mec_init(EC_HOST_CMD_REGION0,
EC_LPC_ADDR_MEMMAP + EC_MEMMAP_SIZE);
}
void cros_ec_lpc_reg_destroy(void)
{
cros_ec_lpc_mec_destroy();
}
#else /* CONFIG_CROS_EC_LPC_MEC */
u8 cros_ec_lpc_read_bytes(unsigned int offset, unsigned int length, u8 *dest)
{
return lpc_read_bytes(offset, length, dest);
}
u8 cros_ec_lpc_write_bytes(unsigned int offset, unsigned int length, u8 *msg)
{
return lpc_write_bytes(offset, length, msg);
}
void cros_ec_lpc_reg_init(void)
{
}
void cros_ec_lpc_reg_destroy(void)
{
}
#endif /* CONFIG_CROS_EC_LPC_MEC */