linux-sg2042/drivers/misc/eeprom/digsy_mtc_eeprom.c

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/*
* EEPROMs access control driver for display configuration EEPROMs
* on DigsyMTC board.
*
* (C) 2011 DENX Software Engineering, Anatolij Gustschin <agust@denx.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/gpio.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/spi/spi.h>
#include <linux/spi/spi_gpio.h>
#include <linux/eeprom_93xx46.h>
#define GPIO_EEPROM_CLK 216
#define GPIO_EEPROM_CS 210
#define GPIO_EEPROM_DI 217
#define GPIO_EEPROM_DO 249
#define GPIO_EEPROM_OE 255
#define EE_SPI_BUS_NUM 1
static void digsy_mtc_op_prepare(void *p)
{
/* enable */
gpio_set_value(GPIO_EEPROM_OE, 0);
}
static void digsy_mtc_op_finish(void *p)
{
/* disable */
gpio_set_value(GPIO_EEPROM_OE, 1);
}
struct eeprom_93xx46_platform_data digsy_mtc_eeprom_data = {
.flags = EE_ADDR8,
.prepare = digsy_mtc_op_prepare,
.finish = digsy_mtc_op_finish,
};
static struct spi_gpio_platform_data eeprom_spi_gpio_data = {
.sck = GPIO_EEPROM_CLK,
.mosi = GPIO_EEPROM_DI,
.miso = GPIO_EEPROM_DO,
.num_chipselect = 1,
};
static struct platform_device digsy_mtc_eeprom = {
.name = "spi_gpio",
.id = EE_SPI_BUS_NUM,
.dev = {
.platform_data = &eeprom_spi_gpio_data,
},
};
static struct spi_board_info digsy_mtc_eeprom_info[] __initdata = {
{
.modalias = "93xx46",
.max_speed_hz = 1000000,
.bus_num = EE_SPI_BUS_NUM,
.chip_select = 0,
.mode = SPI_MODE_0,
.controller_data = (void *)GPIO_EEPROM_CS,
.platform_data = &digsy_mtc_eeprom_data,
},
};
static int __init digsy_mtc_eeprom_devices_init(void)
{
int ret;
ret = gpio_request_one(GPIO_EEPROM_OE, GPIOF_OUT_INIT_HIGH,
"93xx46 EEPROMs OE");
if (ret) {
pr_err("can't request gpio %d\n", GPIO_EEPROM_OE);
return ret;
}
spi_register_board_info(digsy_mtc_eeprom_info,
ARRAY_SIZE(digsy_mtc_eeprom_info));
return platform_device_register(&digsy_mtc_eeprom);
}
device_initcall(digsy_mtc_eeprom_devices_init);