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openwrt-xburst/target/linux/generic/patches-3.7/862-gpio_spi_driver.patch

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THIS CODE IS DEPRECATED.
Please use the new mainline SPI-GPIO driver, as of 2.6.29.
--mb
---
drivers/spi/Kconfig | 9 +
drivers/spi/Makefile | 1
drivers/spi/spi_gpio_old.c | 251 +++++++++++++++++++++++++++++++++++++++
include/linux/spi/spi_gpio_old.h | 73 +++++++++++
4 files changed, 334 insertions(+)
--- /dev/null
+++ b/include/linux/spi/spi_gpio_old.h
@@ -0,0 +1,73 @@
+/*
+ * spi_gpio interface to platform code
+ *
+ * Copyright (c) 2008 Piotr Skamruk
+ * Copyright (c) 2008 Michael Buesch
+ *
+ * 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.
+ */
+#ifndef _LINUX_SPI_SPI_GPIO
+#define _LINUX_SPI_SPI_GPIO
+
+#include <linux/types.h>
+#include <linux/spi/spi.h>
+
+
+/**
+ * struct spi_gpio_platform_data - Data definitions for a SPI-GPIO device.
+ *
+ * This structure holds information about a GPIO-based SPI device.
+ *
+ * @pin_clk: The GPIO pin number of the CLOCK pin.
+ *
+ * @pin_miso: The GPIO pin number of the MISO pin.
+ *
+ * @pin_mosi: The GPIO pin number of the MOSI pin.
+ *
+ * @pin_cs: The GPIO pin number of the CHIPSELECT pin.
+ *
+ * @cs_activelow: If true, the chip is selected when the CS line is low.
+ *
+ * @no_spi_delay: If true, no delay is done in the lowlevel bitbanging.
+ * Note that doing no delay is not standards compliant,
+ * but it might be needed to speed up transfers on some
+ * slow embedded machines.
+ *
+ * @boardinfo_setup: This callback is called after the
+ * SPI master device was registered, but before the
+ * device is registered.
+ * @boardinfo_setup_data: Data argument passed to boardinfo_setup().
+ */
+struct spi_gpio_platform_data {
+ unsigned int pin_clk;
+ unsigned int pin_miso;
+ unsigned int pin_mosi;
+ unsigned int pin_cs;
+ bool cs_activelow;
+ bool no_spi_delay;
+ int (*boardinfo_setup)(struct spi_board_info *bi,
+ struct spi_master *master,
+ void *data);
+ void *boardinfo_setup_data;
+};
+
+/**
+ * SPI_GPIO_PLATDEV_NAME - The platform device name string.
+ *
+ * The name string that has to be used for platform_device_alloc
+ * when allocating a spi-gpio device.
+ */
+#define SPI_GPIO_PLATDEV_NAME "spi-gpio"
+
+/**
+ * spi_gpio_next_id - Get another platform device ID number.
+ *
+ * This returns the next platform device ID number that has to be used
+ * for platform_device_alloc. The ID is opaque and should not be used for
+ * anything else.
+ */
+int spi_gpio_next_id(void);
+
+#endif /* _LINUX_SPI_SPI_GPIO */
--- /dev/null
+++ b/drivers/spi/spi_gpio_old.c
@@ -0,0 +1,251 @@
+/*
+ * Bitbanging SPI bus driver using GPIO API
+ *
+ * Copyright (c) 2008 Piotr Skamruk
+ * Copyright (c) 2008 Michael Buesch
+ *
+ * based on spi_s3c2410_gpio.c
+ * Copyright (c) 2006 Ben Dooks
+ * Copyright (c) 2006 Simtec Electronics
+ * and on i2c-gpio.c
+ * Copyright (C) 2007 Atmel Corporation
+ *
+ * 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/module.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi_bitbang.h>
+#include <linux/spi/spi_gpio_old.h>
+#include <linux/gpio.h>
+#include <asm/atomic.h>
+
+
+struct spi_gpio {
+ struct spi_bitbang bitbang;
+ struct spi_gpio_platform_data *info;
+ struct platform_device *pdev;
+ struct spi_board_info bi;
+};
+
+
+static inline struct spi_gpio *spidev_to_sg(struct spi_device *dev)
+{
+ return dev->controller_data;
+}
+
+static inline void setsck(struct spi_device *dev, int val)
+{
+ struct spi_gpio *sp = spidev_to_sg(dev);
+ gpio_set_value(sp->info->pin_clk, val ? 1 : 0);
+}
+
+static inline void setmosi(struct spi_device *dev, int val)
+{
+ struct spi_gpio *sp = spidev_to_sg(dev);
+ gpio_set_value(sp->info->pin_mosi, val ? 1 : 0);
+}
+
+static inline u32 getmiso(struct spi_device *dev)
+{
+ struct spi_gpio *sp = spidev_to_sg(dev);
+ return gpio_get_value(sp->info->pin_miso) ? 1 : 0;
+}
+
+static inline void do_spidelay(struct spi_device *dev, unsigned nsecs)
+{
+ struct spi_gpio *sp = spidev_to_sg(dev);
+
+ if (!sp->info->no_spi_delay)
+ ndelay(nsecs);
+}
+
+#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 "spi-bitbang-txrx.h"
+
+static u32 spi_gpio_txrx_mode0(struct spi_device *spi,
+ unsigned nsecs, u32 word, u8 bits)
+{
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
+}
+
+static u32 spi_gpio_txrx_mode1(struct spi_device *spi,
+ unsigned nsecs, u32 word, u8 bits)
+{
+ return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits);
+}
+
+static u32 spi_gpio_txrx_mode2(struct spi_device *spi,
+ unsigned nsecs, u32 word, u8 bits)
+{
+ return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits);
+}
+
+static u32 spi_gpio_txrx_mode3(struct spi_device *spi,
+ unsigned nsecs, u32 word, u8 bits)
+{
+ return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits);
+}
+
+static void spi_gpio_chipselect(struct spi_device *dev, int on)
+{
+ struct spi_gpio *sp = spidev_to_sg(dev);
+
+ if (sp->info->cs_activelow)
+ on = !on;
+ gpio_set_value(sp->info->pin_cs, on ? 1 : 0);
+}
+
+static int spi_gpio_probe(struct platform_device *pdev)
+{
+ struct spi_master *master;
+ struct spi_gpio_platform_data *pdata;
+ struct spi_gpio *sp;
+ struct spi_device *spidev;
+ int err;
+
+ pdata = pdev->dev.platform_data;
+ if (!pdata)
+ return -ENXIO;
+
+ err = -ENOMEM;
+ master = spi_alloc_master(&pdev->dev, sizeof(struct spi_gpio));
+ if (!master)
+ goto err_alloc_master;
+
+ sp = spi_master_get_devdata(master);
+ platform_set_drvdata(pdev, sp);
+ sp->info = pdata;
+
+ err = gpio_request(pdata->pin_clk, "spi_clock");
+ if (err)
+ goto err_request_clk;
+ err = gpio_request(pdata->pin_mosi, "spi_mosi");
+ if (err)
+ goto err_request_mosi;
+ err = gpio_request(pdata->pin_miso, "spi_miso");
+ if (err)
+ goto err_request_miso;
+ err = gpio_request(pdata->pin_cs, "spi_cs");
+ if (err)
+ goto err_request_cs;
+
+ sp->bitbang.master = spi_master_get(master);
+ sp->bitbang.master->bus_num = -1;
+ sp->bitbang.master->num_chipselect = 1;
+ sp->bitbang.chipselect = spi_gpio_chipselect;
+ sp->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_txrx_mode0;
+ sp->bitbang.txrx_word[SPI_MODE_1] = spi_gpio_txrx_mode1;
+ sp->bitbang.txrx_word[SPI_MODE_2] = spi_gpio_txrx_mode2;
+ sp->bitbang.txrx_word[SPI_MODE_3] = spi_gpio_txrx_mode3;
+
+ gpio_direction_output(pdata->pin_clk, 0);
+ gpio_direction_output(pdata->pin_mosi, 0);
+ gpio_direction_output(pdata->pin_cs,
+ pdata->cs_activelow ? 1 : 0);
+ gpio_direction_input(pdata->pin_miso);
+
+ err = spi_bitbang_start(&sp->bitbang);
+ if (err)
+ goto err_no_bitbang;
+ err = pdata->boardinfo_setup(&sp->bi, master,
+ pdata->boardinfo_setup_data);
+ if (err)
+ goto err_bi_setup;
+ sp->bi.controller_data = sp;
+ spidev = spi_new_device(master, &sp->bi);
+ if (!spidev)
+ goto err_new_dev;
+
+ return 0;
+
+err_new_dev:
+err_bi_setup:
+ spi_bitbang_stop(&sp->bitbang);
+err_no_bitbang:
+ spi_master_put(sp->bitbang.master);
+ gpio_free(pdata->pin_cs);
+err_request_cs:
+ gpio_free(pdata->pin_miso);
+err_request_miso:
+ gpio_free(pdata->pin_mosi);
+err_request_mosi:
+ gpio_free(pdata->pin_clk);
+err_request_clk:
+ kfree(master);
+
+err_alloc_master:
+ return err;
+}
+
+static int __devexit spi_gpio_remove(struct platform_device *pdev)
+{
+ struct spi_gpio *sp;
+ struct spi_gpio_platform_data *pdata;
+
+ pdata = pdev->dev.platform_data;
+ sp = platform_get_drvdata(pdev);
+
+ gpio_free(pdata->pin_clk);
+ gpio_free(pdata->pin_mosi);
+ gpio_free(pdata->pin_miso);
+ gpio_free(pdata->pin_cs);
+ spi_bitbang_stop(&sp->bitbang);
+ spi_master_put(sp->bitbang.master);
+
+ return 0;
+}
+
+static struct platform_driver spi_gpio_driver = {
+ .driver = {
+ .name = SPI_GPIO_PLATDEV_NAME,
+ .owner = THIS_MODULE,
+ },
+ .probe = spi_gpio_probe,
+ .remove = __devexit_p(spi_gpio_remove),
+};
+
+int spi_gpio_next_id(void)
+{
+ static atomic_t counter = ATOMIC_INIT(-1);
+
+ return atomic_inc_return(&counter);
+}
+EXPORT_SYMBOL(spi_gpio_next_id);
+
+static int __init spi_gpio_init(void)
+{
+ int err;
+
+ err = platform_driver_register(&spi_gpio_driver);
+ if (err)
+ printk(KERN_ERR "spi-gpio: register failed: %d\n", err);
+
+ return err;
+}
+module_init(spi_gpio_init);
+
+static void __exit spi_gpio_exit(void)
+{
+ platform_driver_unregister(&spi_gpio_driver);
+}
+module_exit(spi_gpio_exit);
+
+MODULE_AUTHOR("Piot Skamruk <piotr.skamruk at gmail.com>");
+MODULE_AUTHOR("Michael Buesch");
+MODULE_DESCRIPTION("Platform independent GPIO bitbanging SPI driver");
+MODULE_LICENSE("GPL v2");
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -170,6 +170,15 @@ config SPI_GPIO
GPIO operations, you should be able to leverage that for better
speed with a custom version of this driver; see the source code.
+config SPI_GPIO_OLD
+ tristate "Old GPIO API based bitbanging SPI controller (DEPRECATED)"
+ depends on SPI_MASTER && GENERIC_GPIO
+ select SPI_BITBANG
+ help
+ This code is deprecated. Please use the new mainline SPI-GPIO driver.
+
+ If unsure, say N.
+
config SPI_IMX
tristate "Freescale i.MX SPI controllers"
depends on ARCH_MXC
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -31,6 +31,7 @@ obj-$(CONFIG_SPI_FSL_LIB) += spi-fsl-li
obj-$(CONFIG_SPI_FSL_ESPI) += spi-fsl-espi.o
obj-$(CONFIG_SPI_FSL_SPI) += spi-fsl-spi.o
obj-$(CONFIG_SPI_GPIO) += spi-gpio.o
+obj-$(CONFIG_SPI_GPIO_OLD) += spi_gpio_old.o
obj-$(CONFIG_SPI_IMX) += spi-imx.o
obj-$(CONFIG_SPI_LM70_LLP) += spi-lm70llp.o
obj-$(CONFIG_SPI_MPC512x_PSC) += spi-mpc512x-psc.o