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/* linux/drivers/spi/spi_s3c24xx_gpio.c
*
* Copyright (c) 2006 Ben Dooks
* Copyright (c) 2006 Simtec Electronics
*
* S3C24XX GPIO based SPI driver
*
* 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/spi/spi.h>
#include <linux/spi/spi_bitbang.h>
#include <mach/regs-gpio.h>
#include <mach/spi-gpio.h>
#include <mach/hardware.h>
struct s3c2410_spigpio {
struct spi_bitbang bitbang;
struct s3c2410_spigpio_info *info;
struct platform_device *dev;
};
static inline struct s3c2410_spigpio *spidev_to_sg(struct spi_device *spi)
{
return spi->controller_data;
}
static inline void setsck(struct spi_device *dev, int on)
{
struct s3c2410_spigpio *sg = spidev_to_sg(dev);
s3c2410_gpio_setpin(sg->info->pin_clk, on ? 1 : 0);
}
static inline void setmosi(struct spi_device *dev, int on)
{
struct s3c2410_spigpio *sg = spidev_to_sg(dev);
s3c2410_gpio_setpin(sg->info->pin_mosi, on ? 1 : 0);
}
static inline u32 getmiso(struct spi_device *dev)
{
struct s3c2410_spigpio *sg = spidev_to_sg(dev);
return s3c2410_gpio_getpin(sg->info->pin_miso) ? 1 : 0;
}
#define spidelay(x) ndelay(x)
#define EXPAND_BITBANG_TXRX
#include <linux/spi/spi_bitbang.h>
static u32 s3c2410_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 s3c2410_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 s3c2410_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 s3c2410_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 s3c2410_spigpio_chipselect(struct spi_device *dev, int value)
{
struct s3c2410_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 s3c2410_spigpio_probe(struct platform_device *dev)
{
struct s3c2410_spigpio_info *info;
struct spi_master *master;
struct s3c2410_spigpio *sp;
int ret;
int i;
master = spi_alloc_master(&dev->dev, sizeof(struct s3c2410_spigpio));
if (master == NULL) {
dev_err(&dev->dev, "failed to allocate spi master\n");
ret = -ENOMEM;
goto err;
}
sp = spi_master_get_devdata(master);
platform_set_drvdata(dev, sp);
/* copy in the platform data */
info = sp->info = dev->dev.platform_data;
master->num_chipselect = info->num_chipselect;
/* setup spi bitbang adaptor */
sp->bitbang.master = spi_master_get(master);
sp->bitbang.master->bus_num = info->bus_num;
sp->bitbang.chipselect = s3c2410_spigpio_chipselect;
sp->bitbang.txrx_word[SPI_MODE_0] = s3c2410_spigpio_txrx_mode0;
sp->bitbang.txrx_word[SPI_MODE_1] = s3c2410_spigpio_txrx_mode1;
sp->bitbang.txrx_word[SPI_MODE_2] = s3c2410_spigpio_txrx_mode2;
sp->bitbang.txrx_word[SPI_MODE_3] = s3c2410_spigpio_txrx_mode3;
/* set state of spi pins, always assume that the clock is
* available, but do check the MOSI and MISO. */
s3c2410_gpio_setpin(info->pin_clk, 0);
s3c2410_gpio_cfgpin(info->pin_clk, S3C2410_GPIO_OUTPUT);
if (info->pin_mosi < S3C2410_GPH10) {
s3c2410_gpio_setpin(info->pin_mosi, 0);
s3c2410_gpio_cfgpin(info->pin_mosi, S3C2410_GPIO_OUTPUT);
}
if (info->pin_miso != S3C2410_GPA0 && info->pin_miso < S3C2410_GPH10)
s3c2410_gpio_cfgpin(info->pin_miso, S3C2410_GPIO_INPUT);
ret = spi_bitbang_start(&sp->bitbang);
if (ret)
goto err_no_bitbang;
/* register the chips to go with the board */
for (i = 0; i < sp->info->board_size; i++) {
struct spi_device *spidev;
dev_info(&dev->dev, "registering %p: %s\n",
&sp->info->board_info[i],
sp->info->board_info[i].modalias);
sp->info->board_info[i].controller_data = sp;
spidev = spi_new_device(master, sp->info->board_info + i);
if (spidev)
spidev->max_speed_hz =
sp->info->board_info[i].max_speed_hz;
}
return 0;
err_no_bitbang:
spi_master_put(sp->bitbang.master);
err:
return ret;
}
static int s3c2410_spigpio_remove(struct platform_device *dev)
{
struct s3c2410_spigpio *sp = platform_get_drvdata(dev);
spi_bitbang_stop(&sp->bitbang);
spi_master_put(sp->bitbang.master);
return 0;
}
/* all gpio should be held over suspend/resume, so we should
* not need to deal with this
*/
#define s3c2410_spigpio_suspend NULL
#define s3c2410_spigpio_resume NULL
/* work with hotplug and coldplug */
MODULE_ALIAS("platform:spi_s3c24xx_gpio");
static struct platform_driver s3c2410_spigpio_drv = {
.probe = s3c2410_spigpio_probe,
.remove = s3c2410_spigpio_remove,
.suspend = s3c2410_spigpio_suspend,
.resume = s3c2410_spigpio_resume,
.driver = {
.name = "spi_s3c24xx_gpio",
.owner = THIS_MODULE,
},
};
static int __init s3c2410_spigpio_init(void)
{
return platform_driver_register(&s3c2410_spigpio_drv);
}
static void __exit s3c2410_spigpio_exit(void)
{
platform_driver_unregister(&s3c2410_spigpio_drv);
}
module_init(s3c2410_spigpio_init);
module_exit(s3c2410_spigpio_exit);
MODULE_DESCRIPTION("S3C24XX SPI Driver");
MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
MODULE_LICENSE("GPL");
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