diff options
author | Ingo Molnar <mingo@elte.hu> | 2008-07-18 19:53:16 +0200 |
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committer | Ingo Molnar <mingo@elte.hu> | 2008-07-18 19:53:16 +0200 |
commit | 9b610fda0df5d0f0b0c64242e37441ad1b384aac (patch) | |
tree | 0ea14b15f2e6546f37fe18d8ac3dc83077ec0e55 /arch/mips/txx9/rbtx4938/spi_eeprom.c | |
parent | b8f8c3cf0a4ac0632ec3f0e15e9dc0c29de917af (diff) | |
parent | 5b664cb235e97afbf34db9c4d77f08ebd725335e (diff) |
Merge branch 'linus' into timers/nohz
Diffstat (limited to 'arch/mips/txx9/rbtx4938/spi_eeprom.c')
-rw-r--r-- | arch/mips/txx9/rbtx4938/spi_eeprom.c | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/arch/mips/txx9/rbtx4938/spi_eeprom.c b/arch/mips/txx9/rbtx4938/spi_eeprom.c new file mode 100644 index 000000000000..a7ea8b041c1d --- /dev/null +++ b/arch/mips/txx9/rbtx4938/spi_eeprom.c @@ -0,0 +1,99 @@ +/* + * 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/txx9/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; +} |