/* 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_master_get_devdata(spi->master); } 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, 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; 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 */ info = sp->info = dev->dev.platform_data; /* setup spi bitbang adaptor */ sp->bitbang.master = spi_master_get(master); sp->bitbang.master->bus_num = info->bus_num; sp->bitbang.master->num_chipselect = info->num_chipselect; 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; 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");