diff options
Diffstat (limited to 'arch/mips/txx9/generic')
| -rw-r--r-- | arch/mips/txx9/generic/Makefile | 1 | ||||
| -rw-r--r-- | arch/mips/txx9/generic/spi_eeprom.c | 103 |
2 files changed, 104 insertions, 0 deletions
diff --git a/arch/mips/txx9/generic/Makefile b/arch/mips/txx9/generic/Makefile index 9bb34af26b7..986852cc774 100644 --- a/arch/mips/txx9/generic/Makefile +++ b/arch/mips/txx9/generic/Makefile @@ -8,5 +8,6 @@ obj-$(CONFIG_SOC_TX3927) += setup_tx3927.o irq_tx3927.o obj-$(CONFIG_SOC_TX4927) += mem_tx4927.o setup_tx4927.o irq_tx4927.o obj-$(CONFIG_SOC_TX4938) += mem_tx4927.o setup_tx4938.o irq_tx4938.o obj-$(CONFIG_TOSHIBA_FPCIB0) += smsc_fdc37m81x.o +obj-$(CONFIG_SPI) += spi_eeprom.o EXTRA_CFLAGS += -Werror diff --git a/arch/mips/txx9/generic/spi_eeprom.c b/arch/mips/txx9/generic/spi_eeprom.c new file mode 100644 index 00000000000..75c347238f4 --- /dev/null +++ b/arch/mips/txx9/generic/spi_eeprom.c @@ -0,0 +1,103 @@ +/* + * 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 busid, int chipid, int size) +{ + struct spi_board_info info = { + .modalias = "at25", + .max_speed_hz = 1500000, /* 1.5Mbps */ + .bus_num = busid, + .chip_select = chipid, + /* Mode 0: High-Active, Sample-Then-Shift */ + }; + struct spi_eeprom *eeprom; + eeprom = kzalloc(sizeof(*eeprom), GFP_KERNEL); + if (!eeprom) + return -ENOMEM; + strcpy(eeprom->name, "at250x0"); + eeprom->byte_len = size; + eeprom->page_size = AT250X0_PAGE_SIZE; + eeprom->flags = EE_ADDR1; + info.platform_data = eeprom; + return spi_register_board_info(&info, 1); +} + +/* simple temporary spi driver to provide early access to seeprom. */ + +static struct read_param { + int busid; + 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->busid != spi->master->bus_num || + 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 busid, int chipid, int address, + unsigned char *buf, int len) +{ + int ret; + struct read_param param = { + .busid = busid, + .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; +} |