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/* linux/drivers/spi/spi_s3c64xx_gpio.c
*
* Copyright (c) 2009 Openmoko Inc.
* Author: Matt Hsu <matt_hsu@openmoko.org>
*
* S3C64XX GPIO-SPI driver.
* This driver is based on spi_s3c24xx_gpio.c
*
* Copyright (c) 2006 Ben Dooks
* Copyright (c) 2006 Simtec Electronics
*
* 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/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/platform_device.h>
#include <linux/gpio.h>
#include <linux/spi/spi.h>
#include <linux/spi/spi_bitbang.h>
#include <plat/gpio-cfg.h>
#include <mach/spi-gpio.h>
struct s3c64xx_spigpio {
struct spi_bitbang bitbang;
struct s3c64xx_spigpio_info *info;
struct platform_device *dev;
};
static inline struct s3c64xx_spigpio *spidev_to_sg(struct spi_device *spi)
{
return spi->controller_data;
}
static inline void setsck(struct spi_device *dev, int on)
{
struct s3c64xx_spigpio *sg = spidev_to_sg(dev);
gpio_direction_output(sg->info->pin_clk, on ? 1 : 0);
}
static inline void setmosi(struct spi_device *dev, int on)
{
struct s3c64xx_spigpio *sg = spidev_to_sg(dev);
gpio_direction_output(sg->info->pin_mosi, on ? 1 : 0);
}
static inline u32 getmiso(struct spi_device *dev)
{
struct s3c64xx_spigpio *sg = spidev_to_sg(dev);
return gpio_direction_input(sg->info->pin_miso) ? 1 : 0;
}
#define spidelay(x) ndelay(x)
#define EXPAND_BITBANG_TXRX
#include <linux/spi/spi_bitbang.h>
static u32 s3c64xx_spigpio_txrx_mode0(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
}
static u32 s3c64xx_spigpio_txrx_mode1(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
return bitbang_txrx_be_cpha1(spi, nsecs, 0, word, bits);
}
static u32 s3c64xx_spigpio_txrx_mode2(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
return bitbang_txrx_be_cpha0(spi, nsecs, 1, word, bits);
}
static u32 s3c64xx_spigpio_txrx_mode3(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
return bitbang_txrx_be_cpha1(spi, nsecs, 1, word, bits);
}
static void s3c64xx_spigpio_chipselect(struct spi_device *dev, int value)
{
struct s3c64xx_spigpio *sg = spidev_to_sg(dev);
if (sg->info && sg->info->chip_select)
(sg->info->chip_select)(sg->info, dev->chip_select, value);
}
static int s3c64xx_spigpio_probe(struct platform_device *dev)
{
struct s3c64xx_spigpio_info *info;
struct spi_master *master;
struct s3c64xx_spigpio *spi;
int ret;
int i;
master = spi_alloc_master(&dev->dev, sizeof(struct s3c64xx_spigpio));
if (master == NULL) {
dev_err(&dev->dev, "failed to allocate spi master\n");
ret = -ENOMEM;
goto err;
}
spi = spi_master_get_devdata(master);
/* copy in the platform data */
info = spi->info = dev->dev.platform_data;
master->num_chipselect = info->num_chipselect;
/* setup spi bitbang adaptor */
spi->bitbang.master = spi_master_get(master);
spi->bitbang.master->bus_num = info->bus_num;
spi->bitbang.chipselect = s3c64xx_spigpio_chipselect;
spi->bitbang.txrx_word[SPI_MODE_0] = s3c64xx_spigpio_txrx_mode0;
spi->bitbang.txrx_word[SPI_MODE_1] = s3c64xx_spigpio_txrx_mode1;
spi->bitbang.txrx_word[SPI_MODE_2] = s3c64xx_spigpio_txrx_mode2;
spi->bitbang.txrx_word[SPI_MODE_3] = s3c64xx_spigpio_txrx_mode3;
/* set state of spi pins. */
gpio_direction_output(info->pin_clk, 0);
s3c_gpio_cfgpin(info->pin_clk, S3C_GPIO_OUTPUT);
ret = spi_bitbang_start(&spi->bitbang);
if (ret)
goto err_no_bitbang;
/* register the chips to go with the board */
for (i = 0; i < spi->info->board_size; i++) {
struct spi_device *spidev;
dev_info(&dev->dev, "registering %p: %s\n",
&spi->info->board_info[i],
spi->info->board_info[i].modalias);
spi->info->board_info[i].controller_data = spi;
spidev = spi_new_device(master, spi->info->board_info + i);
if (spidev)
spidev->max_speed_hz =
spi->info->board_info[i].max_speed_hz;
}
return 0;
err_no_bitbang:
spi_master_put(spi->bitbang.master);
err:
return ret;
}
static int s3c64xx_spigpio_remove(struct platform_device *dev)
{
struct s3c64xx_spigpio *sp = platform_get_drvdata(dev);
spi_bitbang_stop(&sp->bitbang);
spi_master_put(sp->bitbang.master);
return 0;
}
#define s3c64xx_spigpio_suspend NULL
#define s3c64xx_spigpio_resume NULL
static struct platform_driver s3c64xx_spigpio_drv = {
.probe = s3c64xx_spigpio_probe,
.remove = s3c64xx_spigpio_remove,
.suspend = s3c64xx_spigpio_suspend,
.resume = s3c64xx_spigpio_resume,
.driver = {
.name = "spi_s3c64xx_gpio",
.owner = THIS_MODULE,
},
};
static int __init s3c64xx_spigpio_init(void)
{
return platform_driver_register(&s3c64xx_spigpio_drv);
}
static void __exit s3c64xx_spigpio_exit(void)
{
platform_driver_unregister(&s3c64xx_spigpio_drv);
}
module_init(s3c64xx_spigpio_init);
module_exit(s3c64xx_spigpio_exit);
MODULE_DESCRIPTION("S3C64XX GPIO-SPI Driver");
MODULE_AUTHOR("Matt Hsu, <matt_hsu@openmoko.org>");
MODULE_LICENSE("GPLv2");
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