You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
99 lines
2.3 KiB
99 lines
2.3 KiB
/*
|
|
* linux/arch/mips/tx4938/toshiba_rbtx4938/spi_eeprom.c
|
|
* Copyright (C) 2000-2001 Toshiba Corporation
|
|
*
|
|
* 2003-2005 (c) MontaVista Software, Inc. This file is licensed under the
|
|
* terms of the GNU General Public License version 2. This program is
|
|
* licensed "as is" without any warranty of any kind, whether express
|
|
* or implied.
|
|
*
|
|
* Support for TX4938 in 2.6 - Manish Lachwani (mlachwani@mvista.com)
|
|
*/
|
|
#include <linux/init.h>
|
|
#include <linux/device.h>
|
|
#include <linux/spi/spi.h>
|
|
#include <linux/spi/eeprom.h>
|
|
#include <asm/tx4938/spi.h>
|
|
|
|
#define AT250X0_PAGE_SIZE 8
|
|
|
|
/* register board information for at25 driver */
|
|
int __init spi_eeprom_register(int chipid)
|
|
{
|
|
static struct spi_eeprom eeprom = {
|
|
.name = "at250x0",
|
|
.byte_len = 128,
|
|
.page_size = AT250X0_PAGE_SIZE,
|
|
.flags = EE_ADDR1,
|
|
};
|
|
struct spi_board_info info = {
|
|
.modalias = "at25",
|
|
.max_speed_hz = 1500000, /* 1.5Mbps */
|
|
.bus_num = 0,
|
|
.chip_select = chipid,
|
|
.platform_data = &eeprom,
|
|
/* Mode 0: High-Active, Sample-Then-Shift */
|
|
};
|
|
|
|
return spi_register_board_info(&info, 1);
|
|
}
|
|
|
|
/* simple temporary spi driver to provide early access to seeprom. */
|
|
|
|
static struct read_param {
|
|
int chipid;
|
|
int address;
|
|
unsigned char *buf;
|
|
int len;
|
|
} *read_param;
|
|
|
|
static int __init early_seeprom_probe(struct spi_device *spi)
|
|
{
|
|
int stat = 0;
|
|
u8 cmd[2];
|
|
int len = read_param->len;
|
|
char *buf = read_param->buf;
|
|
int address = read_param->address;
|
|
|
|
dev_info(&spi->dev, "spiclk %u KHz.\n",
|
|
(spi->max_speed_hz + 500) / 1000);
|
|
if (read_param->chipid != spi->chip_select)
|
|
return -ENODEV;
|
|
while (len > 0) {
|
|
/* spi_write_then_read can only work with small chunk */
|
|
int c = len < AT250X0_PAGE_SIZE ? len : AT250X0_PAGE_SIZE;
|
|
cmd[0] = 0x03; /* AT25_READ */
|
|
cmd[1] = address;
|
|
stat = spi_write_then_read(spi, cmd, sizeof(cmd), buf, c);
|
|
buf += c;
|
|
len -= c;
|
|
address += c;
|
|
}
|
|
return stat;
|
|
}
|
|
|
|
static struct spi_driver early_seeprom_driver __initdata = {
|
|
.driver = {
|
|
.name = "at25",
|
|
.owner = THIS_MODULE,
|
|
},
|
|
.probe = early_seeprom_probe,
|
|
};
|
|
|
|
int __init spi_eeprom_read(int chipid, int address,
|
|
unsigned char *buf, int len)
|
|
{
|
|
int ret;
|
|
struct read_param param = {
|
|
.chipid = chipid,
|
|
.address = address,
|
|
.buf = buf,
|
|
.len = len
|
|
};
|
|
|
|
read_param = ¶m;
|
|
ret = spi_register_driver(&early_seeprom_driver);
|
|
if (!ret)
|
|
spi_unregister_driver(&early_seeprom_driver);
|
|
return ret;
|
|
}
|
|
|