mirror of https://gitee.com/openkylin/linux.git
104 lines
2.6 KiB
C
104 lines
2.6 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* EEPROMs access control driver for display configuration EEPROMs
|
|
* on DigsyMTC board.
|
|
*
|
|
* (C) 2011 DENX Software Engineering, Anatolij Gustschin <agust@denx.de>
|
|
*
|
|
* FIXME: this driver is used on a device-tree probed platform: it
|
|
* should be defined as a bit-banged SPI device and probed from the device
|
|
* tree and not like this with static grabbing of a few numbered GPIO
|
|
* lines at random.
|
|
*
|
|
* Add proper SPI and EEPROM in arch/powerpc/boot/dts/digsy_mtc.dts
|
|
* and delete this driver.
|
|
*/
|
|
|
|
#include <linux/gpio.h>
|
|
#include <linux/gpio/machine.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 = {
|
|
.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 gpiod_lookup_table eeprom_spi_gpiod_table = {
|
|
.dev_id = "spi_gpio",
|
|
.table = {
|
|
GPIO_LOOKUP("gpio@b00", GPIO_EEPROM_CLK,
|
|
"sck", GPIO_ACTIVE_HIGH),
|
|
GPIO_LOOKUP("gpio@b00", GPIO_EEPROM_DI,
|
|
"mosi", GPIO_ACTIVE_HIGH),
|
|
GPIO_LOOKUP("gpio@b00", GPIO_EEPROM_DO,
|
|
"miso", GPIO_ACTIVE_HIGH),
|
|
GPIO_LOOKUP("gpio@b00", GPIO_EEPROM_CS,
|
|
"cs", GPIO_ACTIVE_HIGH),
|
|
{ },
|
|
},
|
|
};
|
|
|
|
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,
|
|
.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;
|
|
}
|
|
gpiod_add_lookup_table(&eeprom_spi_gpiod_table);
|
|
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);
|