-/*
- * Atheros AP83 board specific SPI Controller driver
- *
- * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
- *
- * 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/io.h>
-#include <linux/spi/spi.h>
-#include <linux/spi/spi_bitbang.h>
-#include <linux/bitops.h>
-#include <linux/gpio.h>
-
-#include <asm/mach-ar71xx/ar71xx.h>
-#include <asm/mach-ar71xx/platform.h>
-
-#define DRV_DESC "Atheros AP83 board SPI Controller driver"
-#define DRV_VERSION "0.1.0"
-#define DRV_NAME "ap83-spi"
-
-#define AP83_SPI_CLK_HIGH (1 << 23)
-#define AP83_SPI_CLK_LOW 0
-#define AP83_SPI_MOSI_HIGH (1 << 22)
-#define AP83_SPI_MOSI_LOW 0
-
-#define AP83_SPI_GPIO_CS 1
-#define AP83_SPI_GPIO_MISO 3
-
-struct ap83_spi {
- struct spi_bitbang bitbang;
- void __iomem *base;
- u32 addr;
-
- struct platform_device *pdev;
-};
-
-static inline u32 ap83_spi_rr(struct ap83_spi *sp, u32 reg)
-{
- return __raw_readl(sp->base + reg);
-}
-
-static inline struct ap83_spi *spidev_to_sp(struct spi_device *spi)
-{
- return spi_master_get_devdata(spi->master);
-}
-
-static inline void setsck(struct spi_device *spi, int val)
-{
- struct ap83_spi *sp = spidev_to_sp(spi);
-
- if (val)
- sp->addr |= AP83_SPI_CLK_HIGH;
- else
- sp->addr &= ~AP83_SPI_CLK_HIGH;
-
- dev_dbg(&spi->dev, "addr=%08x, SCK set to %s\n",
- sp->addr, (val) ? "HIGH" : "LOW");
-
- ap83_spi_rr(sp, sp->addr);
-}
-
-static inline void setmosi(struct spi_device *spi, int val)
-{
- struct ap83_spi *sp = spidev_to_sp(spi);
-
- if (val)
- sp->addr |= AP83_SPI_MOSI_HIGH;
- else
- sp->addr &= ~AP83_SPI_MOSI_HIGH;
-
- dev_dbg(&spi->dev, "addr=%08x, MOSI set to %s\n",
- sp->addr, (val) ? "HIGH" : "LOW");
-
- ap83_spi_rr(sp, sp->addr);
-}
-
-static inline u32 getmiso(struct spi_device *spi)
-{
- u32 ret;
-
- ret = gpio_get_value(AP83_SPI_GPIO_MISO) ? 1 : 0;
- dev_dbg(&spi->dev, "get MISO: %d\n", ret);
-
- return ret;
-}
-
-static inline void do_spidelay(struct spi_device *spi, unsigned nsecs)
-{
- ndelay(nsecs);
-}
-
-static void ap83_spi_chipselect(struct spi_device *spi, int on)
-{
- struct ap83_spi *sp = spidev_to_sp(spi);
-
- dev_dbg(&spi->dev, "set CS to %d\n", (on) ? 0 : 1);
-
- if (on) {
- ar71xx_flash_acquire();
-
- sp->addr = 0;
- ap83_spi_rr(sp, sp->addr);
-
- gpio_set_value(AP83_SPI_GPIO_CS, 0);
- } else {
- gpio_set_value(AP83_SPI_GPIO_CS, 1);
- ar71xx_flash_release();
- }
-}
-
-#define spidelay(nsecs) \
- do { \
- /* Steal the spi_device pointer from our caller. \
- * The bitbang-API should probably get fixed here... */ \
- do_spidelay(spi, nsecs); \
- } while (0)
-
-#define EXPAND_BITBANG_TXRX
-#include <linux/spi/spi_bitbang.h>
-#include "spi_bitbang_txrx.h"
-
-static u32 ap83_spi_txrx_mode0(struct spi_device *spi,
- unsigned nsecs, u32 word, u8 bits)
-{
- dev_dbg(&spi->dev, "TXRX0 word=%08x, bits=%u\n", word, bits);
- return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
-}
-
-static u32 ap83_spi_txrx_mode1(struct spi_device *spi,
- unsigned nsecs, u32 word, u8 bits)
-{
- dev_dbg(&spi->dev, "TXRX1 word=%08x, bits=%u\n", word, bits);
- return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits);
-}
-
-static u32 ap83_spi_txrx_mode2(struct spi_device *spi,
- unsigned nsecs, u32 word, u8 bits)
-{
- dev_dbg(&spi->dev, "TXRX2 word=%08x, bits=%u\n", word, bits);
- return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits);
-}
-
-static u32 ap83_spi_txrx_mode3(struct spi_device *spi,
- unsigned nsecs, u32 word, u8 bits)
-{
- dev_dbg(&spi->dev, "TXRX3 word=%08x, bits=%u\n", word, bits);
- return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits);
-}
-
-static int ap83_spi_probe(struct platform_device *pdev)
-{
- struct spi_master *master;
- struct ap83_spi *sp;
- struct ap83_spi_platform_data *pdata;
- struct resource *r;
- int ret;
-
- ret = gpio_request(AP83_SPI_GPIO_MISO, "spi-miso");
- if (ret) {
- dev_err(&pdev->dev, "gpio request failed for MISO\n");
- return ret;
- }
-
- ret = gpio_request(AP83_SPI_GPIO_CS, "spi-cs");
- if (ret) {
- dev_err(&pdev->dev, "gpio request failed for CS\n");
- goto err_free_miso;
- }
-
- ret = gpio_direction_input(AP83_SPI_GPIO_MISO);
- if (ret) {
- dev_err(&pdev->dev, "unable to set direction of MISO\n");
- goto err_free_cs;
- }
-
- ret = gpio_direction_output(AP83_SPI_GPIO_CS, 0);
- if (ret) {
- dev_err(&pdev->dev, "unable to set direction of CS\n");
- goto err_free_cs;
- }
-
- master = spi_alloc_master(&pdev->dev, sizeof(*sp));
- if (master == NULL) {
- dev_err(&pdev->dev, "failed to allocate spi master\n");
- return -ENOMEM;
- }
-
- sp = spi_master_get_devdata(master);
- platform_set_drvdata(pdev, sp);
-
- pdata = pdev->dev.platform_data;
-
- sp->bitbang.master = spi_master_get(master);
- sp->bitbang.chipselect = ap83_spi_chipselect;
- sp->bitbang.txrx_word[SPI_MODE_0] = ap83_spi_txrx_mode0;
- sp->bitbang.txrx_word[SPI_MODE_1] = ap83_spi_txrx_mode1;
- sp->bitbang.txrx_word[SPI_MODE_2] = ap83_spi_txrx_mode2;
- sp->bitbang.txrx_word[SPI_MODE_3] = ap83_spi_txrx_mode3;
-
- sp->bitbang.master->bus_num = pdev->id;
- sp->bitbang.master->num_chipselect = 1;
-
- r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (r == NULL) {
- ret = -ENOENT;
- goto err_spi_put;
- }
-
- sp->base = ioremap_nocache(r->start, r->end - r->start + 1);
- if (!sp->base) {
- ret = -ENXIO;
- goto err_spi_put;
- }
-
- ret = spi_bitbang_start(&sp->bitbang);
- if (!ret)
- goto err_unmap;
-
- dev_info(&pdev->dev, "AP83 SPI adapter at %08x\n", r->start);
-
- return 0;
-
-err_unmap:
- iounmap(sp->base);
-err_spi_put:
- platform_set_drvdata(pdev, NULL);
- spi_master_put(sp->bitbang.master);
-
-err_free_cs:
- gpio_free(AP83_SPI_GPIO_CS);
-err_free_miso:
- gpio_free(AP83_SPI_GPIO_MISO);
- return ret;
-}
-
-static int ap83_spi_remove(struct platform_device *pdev)
-{
- struct ap83_spi *sp = platform_get_drvdata(pdev);
-
- spi_bitbang_stop(&sp->bitbang);
- iounmap(sp->base);
- platform_set_drvdata(pdev, NULL);
- spi_master_put(sp->bitbang.master);
-
- return 0;
-}
-
-static struct platform_driver ap83_spi_drv = {
- .probe = ap83_spi_probe,
- .remove = ap83_spi_remove,
- .driver = {
- .name = DRV_NAME,
- .owner = THIS_MODULE,
- },
-};
-
-static int __init ap83_spi_init(void)
-{
- return platform_driver_register(&ap83_spi_drv);
-}
-module_init(ap83_spi_init);
-
-static void __exit ap83_spi_exit(void)
-{
- platform_driver_unregister(&ap83_spi_drv);
-}
-module_exit(ap83_spi_exit);
-
-MODULE_ALIAS("platform:" DRV_NAME);
-MODULE_DESCRIPTION(DRV_DESC);
-MODULE_VERSION(DRV_VERSION);
-MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
-MODULE_LICENSE("GPL v2");
projects / openwrt / svn-archive / archive.git / blobdiff