[PATCH] S3C24XX: GPIO based SPI driver
SPI driver for SPI by GPIO on the Samsung S3C24XX series of SoC processors. Signed-off-by: Ben Dooks <ben-linux@fluff.org> Cc: Greg KH <greg@kroah.com> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Ben Dooks
committed by
Linus Torvalds
Linus Torvalds
parent
1b81d6637d
commit
1fc7547d4b
188
drivers/spi/spi_s3c24xx_gpio.c
Normal file
188
drivers/spi/spi_s3c24xx_gpio.c
Normal file
@ -0,0 +1,188 @@
|
||||
/* 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/config.h>
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/init.h>
|
||||
#include <linux/delay.h>
|
||||
#include <linux/spinlock.h>
|
||||
#include <linux/platform_device.h>
|
||||
|
||||
#include <linux/spi/spi.h>
|
||||
#include <linux/spi/spi_bitbang.h>
|
||||
|
||||
#include <asm/arch/regs-gpio.h>
|
||||
#include <asm/arch/spi-gpio.h>
|
||||
#include <asm/arch/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 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, value);
|
||||
}
|
||||
|
||||
static int s3c2410_spigpio_probe(struct platform_device *dev)
|
||||
{
|
||||
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 plkatform data */
|
||||
sp->info = dev->dev.platform_data;
|
||||
|
||||
/* setup spi bitbang adaptor */
|
||||
sp->bitbang.master = spi_master_get(master);
|
||||
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;
|
||||
|
||||
/* set state of spi pins */
|
||||
s3c2410_gpio_setpin(sp->info->pin_clk, 0);
|
||||
s3c2410_gpio_setpin(sp->info->pin_mosi, 0);
|
||||
|
||||
s3c2410_gpio_cfgpin(sp->info->pin_clk, S3C2410_GPIO_OUTPUT);
|
||||
s3c2410_gpio_cfgpin(sp->info->pin_mosi, S3C2410_GPIO_OUTPUT);
|
||||
s3c2410_gpio_cfgpin(sp->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++) {
|
||||
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;
|
||||
spi_new_device(master, sp->info->board_info + i);
|
||||
}
|
||||
|
||||
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
|
||||
|
||||
|
||||
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 = "s3c24xx-spi-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");
|
||||
Reference in New Issue
Block a user