Update GPIO-based MMC driver

SVN-Revision: 11864

1 files changed, 554 insertions, 0 deletions

diff --git a/target/linux/generic-2.6/patches-2.6.25/922-gpiommc.patch b/target/linux/generic-2.6/patches-2.6.25/922-gpiommc.patch
new file mode 100644
index 0000000000..8253202c09
--- /dev/null
+++ b/target/linux/generic-2.6/patches-2.6.25/922-gpiommc.patch
@@ -0,0 +1,554 @@
+Index: linux-2.6.25.10/drivers/mmc/host/gpiommc.c
+===================================================================
+--- /dev/null	1970-01-01 00:00:00.000000000 +0000
++++ linux-2.6.25.10/drivers/mmc/host/gpiommc.c	2008-07-18 22:31:00.000000000 +0200
+@@ -0,0 +1,328 @@
++/*
++ * Driver an MMC/SD card on a bitbanging GPIO SPI bus.
++ * This module hooks up the mmc_spi and spi_gpio modules and also
++ * provides a sysfs interface.
++ *
++ * Copyright 2008 Michael Buesch <mb@bu3sch.de>
++ *
++ * Licensed under the GNU/GPL. See COPYING for details.
++ */
++
++#include <linux/mmc/gpiommc.h>
++#include <linux/platform_device.h>
++#include <linux/list.h>
++#include <linux/mutex.h>
++#include <linux/spi/spi_gpio.h>
++
++
++#define PFX				"gpio-mmc: "
++#define GPIOMMC_MAX_NAMELEN_STR		__stringify(GPIOMMC_MAX_NAMELEN)
++
++struct gpiommc_device {
++	struct platform_device *pdev;
++	struct platform_device *spi_pdev;
++	struct spi_board_info boardinfo;
++};
++
++
++MODULE_DESCRIPTION("GPIO based MMC driver");
++MODULE_AUTHOR("Michael Buesch");
++MODULE_LICENSE("GPL");
++
++
++static int gpiommc_boardinfo_setup(struct spi_board_info *bi,
++				   struct spi_master *master,
++				   void *data)
++{
++	struct gpiommc_device *d = data;
++	struct gpiommc_platform_data *pdata = d->pdev->dev.platform_data;
++
++	/* Bind the SPI master to the MMC-SPI host driver. */
++	strlcpy(bi->modalias, "mmc_spi", sizeof(bi->modalias));
++
++	bi->max_speed_hz = pdata->max_bus_speed;
++	bi->bus_num = master->bus_num;
++	bi->mode = pdata->mode;
++
++	return 0;
++}
++
++static int gpiommc_probe(struct platform_device *pdev)
++{
++	struct gpiommc_platform_data *mmc_pdata = pdev->dev.platform_data;
++	struct spi_gpio_platform_data spi_pdata;
++	struct gpiommc_device *d;
++	int err;
++
++	err = -ENXIO;
++	if (!mmc_pdata)
++		goto error;
++
++	/* Allocate the GPIO-MMC device */
++	err = -ENOMEM;
++	d = kzalloc(sizeof(*d), GFP_KERNEL);
++	if (!d)
++		goto error;
++	d->pdev = pdev;
++
++	/* Create the SPI-GPIO device */
++	d->spi_pdev = platform_device_alloc(SPI_GPIO_PLATDEV_NAME,
++					    spi_gpio_next_id());
++	if (!d->spi_pdev)
++		goto err_free_d;
++
++	memset(&spi_pdata, 0, sizeof(spi_pdata));
++	spi_pdata.pin_clk = mmc_pdata->pins.gpio_clk;
++	spi_pdata.pin_miso = mmc_pdata->pins.gpio_do;
++	spi_pdata.pin_mosi = mmc_pdata->pins.gpio_di;
++	spi_pdata.pin_cs = mmc_pdata->pins.gpio_cs;
++	spi_pdata.cs_activelow = mmc_pdata->pins.cs_activelow;
++	spi_pdata.no_spi_delay = mmc_pdata->no_spi_delay;
++	spi_pdata.boardinfo_setup = gpiommc_boardinfo_setup;
++	spi_pdata.boardinfo_setup_data = d;
++
++	err = platform_device_add_data(d->spi_pdev, &spi_pdata,
++				       sizeof(spi_pdata));
++	if (err)
++		goto err_free_pdev;
++	err = platform_device_add(d->spi_pdev);
++	if (err)
++		goto err_free_pdata;
++	platform_set_drvdata(pdev, d);
++
++	printk(KERN_INFO PFX "MMC-Card \"%s\" "
++	       "attached to GPIO pins di=%u, do=%u, clk=%u, cs=%u\n",
++	       mmc_pdata->name, mmc_pdata->pins.gpio_di,
++	       mmc_pdata->pins.gpio_do,
++	       mmc_pdata->pins.gpio_clk,
++	       mmc_pdata->pins.gpio_cs);
++
++	return 0;
++
++err_free_pdata:
++	kfree(d->spi_pdev->dev.platform_data);
++	d->spi_pdev->dev.platform_data = NULL;
++err_free_pdev:
++	platform_device_put(d->spi_pdev);
++err_free_d:
++	kfree(d);
++error:
++	return err;
++}
++
++static int gpiommc_remove(struct platform_device *pdev)
++{
++	struct gpiommc_device *d = platform_get_drvdata(pdev);
++	struct gpiommc_platform_data *pdata = d->pdev->dev.platform_data;
++
++	platform_device_unregister(d->spi_pdev);
++	printk(KERN_INFO PFX "GPIO based MMC-Card \"%s\" removed\n", pdata->name);
++	platform_device_put(d->spi_pdev);
++
++	return 0;
++}
++
++/* Wrapper for the platform data with context data for the sysfs interface. */
++struct gpiommc_sysfs_platform_data {
++	struct gpiommc_platform_data p; /* Keep as first element */
++
++	/* The platform device that we allocated. */
++	struct platform_device *pdev;
++	/* gpiommc_sysfs_list */
++	struct list_head list;
++};
++
++static LIST_HEAD(gpiommc_sysfs_list);
++static DEFINE_MUTEX(gpiommc_sysfs_mutex);
++
++static struct gpiommc_sysfs_platform_data *gpiommc_sysfs_find_dev(const char *name)
++{
++	struct gpiommc_sysfs_platform_data *pdata;
++
++	list_for_each_entry(pdata, &gpiommc_sysfs_list, list) {
++		if (strcmp(pdata->p.name, name) == 0)
++			return pdata;
++	}
++
++	return NULL;
++}
++
++static ssize_t gpiommc_add_store(struct device_driver *drv,
++				 const char *buf, size_t count)
++{
++	int res, err;
++	struct gpiommc_sysfs_platform_data pdata_local, *pdata;
++	struct platform_device *pdev;
++	unsigned int no_spi_delay = 0, mode = 0, csactivelow = 0;
++
++	mutex_lock(&gpiommc_sysfs_mutex);
++
++	pdata = &pdata_local;
++	memset(pdata, 0, sizeof(*pdata));
++
++	err = -EINVAL;
++	res = sscanf(buf, "%" GPIOMMC_MAX_NAMELEN_STR "s %u %u %u %u %u %u %u %u",
++		     pdata->p.name,
++		     &pdata->p.pins.gpio_di,
++		     &pdata->p.pins.gpio_do,
++		     &pdata->p.pins.gpio_clk,
++		     &pdata->p.pins.gpio_cs,
++		     &mode,
++		     &pdata->p.max_bus_speed,
++		     &no_spi_delay,
++		     &csactivelow);
++	pdata->p.mode = mode;
++	pdata->p.no_spi_delay = !!no_spi_delay;
++	pdata->p.pins.cs_activelow = !!csactivelow;
++	if (res < 9)
++		pdata->p.pins.cs_activelow = 1; /* Default: CS = activelow */
++	if (res < 8)
++		pdata->p.no_spi_delay = 0; /* Default: Delay turned on */
++	if (res < 7)
++		pdata->p.max_bus_speed = 5000000; /* Default: 5Mhz */
++	if (res < 6)
++		pdata->p.mode = 0; /* Default: SPI mode 0 */
++	if (res < 5 || res > 9)
++		goto out; /* First 5 args are mandatory. */
++
++	/* Convert mode so that the SPI subsystem does understand it. */
++	switch (pdata->p.mode) {
++	case 0:
++		pdata->p.mode = SPI_MODE_0;
++		break;
++	case 1:
++		pdata->p.mode = SPI_MODE_1;
++		break;
++	case 2:
++		pdata->p.mode = SPI_MODE_2;
++		break;
++	case 3:
++		pdata->p.mode = SPI_MODE_3;
++		break;
++	default:
++		goto out; /* Invalid mode */
++	}
++
++	err = -EEXIST;
++	if (gpiommc_sysfs_find_dev(pdata->p.name))
++		goto out;
++
++	err = -ENOMEM;
++	pdev = platform_device_alloc(GPIOMMC_PLATDEV_NAME, gpiommc_next_id());
++	if (!pdev)
++		goto out;
++
++	err = platform_device_add_data(pdev, pdata, sizeof(*pdata));
++	if (err)
++		goto err_free_pdev;
++	pdata = pdev->dev.platform_data;
++
++	err = platform_device_add(pdev);
++	if (err)
++		goto err_free_pdev;
++
++	pdata->pdev = pdev;
++	INIT_LIST_HEAD(&pdata->list);
++	list_add(&pdata->list, &gpiommc_sysfs_list);
++
++	err = 0;
++out:
++	mutex_unlock(&gpiommc_sysfs_mutex);
++
++	return err ? err : count;
++
++err_free_pdev:
++	platform_device_put(pdev);
++	goto out;
++}
++
++static ssize_t gpiommc_remove_store(struct device_driver *drv,
++				    const char *buf, size_t count)
++{
++	struct gpiommc_sysfs_platform_data *pdata;
++	int err;
++
++	mutex_lock(&gpiommc_sysfs_mutex);
++
++	err = -ENODEV;
++	pdata = gpiommc_sysfs_find_dev(buf);
++	if (!pdata)
++		goto out;
++
++	list_del(&pdata->list);
++	platform_device_unregister(pdata->pdev);
++
++out:
++	mutex_unlock(&gpiommc_sysfs_mutex);
++
++	return err ? err : count;
++}
++
++static DRIVER_ATTR(add, 0200,
++		   NULL, gpiommc_add_store);
++static DRIVER_ATTR(remove, 0200,
++		   NULL, gpiommc_remove_store);
++
++static struct platform_driver gpiommc_plat_driver = {
++	.probe	= gpiommc_probe,
++	.remove	= gpiommc_remove,
++	.driver	= {
++		.name	= GPIOMMC_PLATDEV_NAME,
++		.owner	= THIS_MODULE,
++	},
++};
++
++int gpiommc_next_id(void)
++{
++	static atomic_t counter = ATOMIC_INIT(-1);
++
++	return atomic_inc_return(&counter);
++}
++EXPORT_SYMBOL(gpiommc_next_id);
++
++static int __init gpiommc_modinit(void)
++{
++	int err;
++
++	err = platform_driver_register(&gpiommc_plat_driver);
++	if (err)
++		return err;
++	err = driver_create_file(&gpiommc_plat_driver.driver,
++				 &driver_attr_add);
++	if (err)
++		goto err_drv_unreg;
++	err = driver_create_file(&gpiommc_plat_driver.driver,
++				 &driver_attr_remove);
++	if (err)
++		goto err_remove_add;
++
++	return 0;
++
++err_remove_add:
++	driver_remove_file(&gpiommc_plat_driver.driver,
++			   &driver_attr_add);
++err_drv_unreg:
++	platform_driver_unregister(&gpiommc_plat_driver);
++	return err;
++}
++module_init(gpiommc_modinit);
++
++static void __exit gpiommc_modexit(void)
++{
++	struct gpiommc_sysfs_platform_data *pdata, *pdata_tmp;
++
++	driver_remove_file(&gpiommc_plat_driver.driver,
++			   &driver_attr_remove);
++	driver_remove_file(&gpiommc_plat_driver.driver,
++			   &driver_attr_add);
++
++	mutex_lock(&gpiommc_sysfs_mutex);
++	list_for_each_entry_safe(pdata, pdata_tmp, &gpiommc_sysfs_list, list) {
++		list_del(&pdata->list);
++		platform_device_unregister(pdata->pdev);
++	}
++	mutex_unlock(&gpiommc_sysfs_mutex);
++
++	platform_driver_unregister(&gpiommc_plat_driver);
++}
++module_exit(gpiommc_modexit);
+Index: linux-2.6.25.10/drivers/mmc/host/Kconfig
+===================================================================
+--- linux-2.6.25.10.orig/drivers/mmc/host/Kconfig	2008-07-18 22:30:36.000000000 +0200
++++ linux-2.6.25.10/drivers/mmc/host/Kconfig	2008-07-18 22:31:00.000000000 +0200
+@@ -130,3 +130,23 @@ config MMC_SPI
+ 
+ 	  If unsure, or if your system has no SPI master driver, say N.
+ 
++config GPIOMMC
++	tristate "MMC/SD over GPIO-based SPI"
++	depends on MMC && MMC_SPI && SPI_GPIO
++	help
++	  This driver hooks up the mmc_spi and spi_gpio modules so that
++	  MMC/SD cards can be used on a GPIO based bus by bitbanging
++	  the SPI protocol in software.
++
++	  This driver provides a sysfs interface to dynamically create
++	  and destroy GPIO-based MMC/SD card interfaces. It also provides
++	  a platform device interface API.
++	  See Documentation/gpiommc.txt for details.
++
++	  The module will be called gpiommc.
++
++	  If unsure, say N.
++
++config MMC_S3C
++	tristate "Samsung S3C SD/MMC Card Interface support"
++	depends on ARCH_S3C2410 && MMC
+Index: linux-2.6.25.10/drivers/mmc/host/Makefile
+===================================================================
+--- linux-2.6.25.10.orig/drivers/mmc/host/Makefile	2008-07-18 22:30:36.000000000 +0200
++++ linux-2.6.25.10/drivers/mmc/host/Makefile	2008-07-18 22:31:20.000000000 +0200
+@@ -18,3 +18,4 @@ obj-$(CONFIG_MMC_AT91)		+= at91_mci.o
+ obj-$(CONFIG_MMC_TIFM_SD)	+= tifm_sd.o
+ obj-$(CONFIG_MMC_SPI)		+= mmc_spi.o
+ 
++obj-$(CONFIG_GPIOMMC)		+= gpiommc.o
+Index: linux-2.6.25.10/include/linux/mmc/gpiommc.h
+===================================================================
+--- /dev/null	1970-01-01 00:00:00.000000000 +0000
++++ linux-2.6.25.10/include/linux/mmc/gpiommc.h	2008-07-18 22:31:00.000000000 +0200
+@@ -0,0 +1,62 @@
++/*
++ * Device driver for MMC/SD cards driven over a GPIO bus.
++ *
++ * Copyright (c) 2008 Michael Buesch
++ *
++ * Licensed under the GNU/GPL version 2.
++ */
++#ifndef LINUX_GPIOMMC_H_
++#define LINUX_GPIOMMC_H_
++
++#include <linux/types.h>
++
++
++#define GPIOMMC_MAX_NAMELEN		15
++
++/** struct gpiommc_pins - Hardware pin assignments
++ * @gpio_di: The GPIO number of the DATA IN pin
++ * @gpio_do: The GPIO number of the DATA OUT pin
++ * @gpio_clk: The GPIO number of the CLOCK pin
++ * @gpio_cs: The GPIO number of the CHIPSELECT pin
++ * @cs_activelow: If true, the chip is considered selected if @gpio_cs is low.
++ */
++struct gpiommc_pins {
++	unsigned int gpio_di;
++	unsigned int gpio_do;
++	unsigned int gpio_clk;
++	unsigned int gpio_cs;
++	bool cs_activelow;
++};
++
++/** struct gpiommc_platform_data - Platform data for a MMC-over-SPI-GPIO device.
++ * @name: The unique name string of the device.
++ * @pins: The hardware pin assignments.
++ * @mode: The hardware mode. This is either SPI_MODE_0,
++ *        SPI_MODE_1, SPI_MODE_2 or SPI_MODE_3. See the SPI documentation.
++ * @no_spi_delay: Do not use delays in the lowlevel SPI bitbanging code.
++ *                This is not standards compliant, but may be required for some
++ *                embedded machines to gain reasonable speed.
++ * @max_bus_speed: The maximum speed of the SPI bus, in Hertz.
++ */
++struct gpiommc_platform_data {
++	char name[GPIOMMC_MAX_NAMELEN + 1];
++	struct gpiommc_pins pins;
++	u8 mode;
++	bool no_spi_delay;
++	unsigned int max_bus_speed;
++};
++
++/** GPIOMMC_PLATDEV_NAME - The platform device name string.
++ * The name string that has to be used for platform_device_alloc
++ * when allocating a gpiommc device.
++ */
++#define GPIOMMC_PLATDEV_NAME	"gpiommc"
++
++/** gpiommc_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 gpiommc_next_id(void);
++
++#endif /* LINUX_GPIOMMC_H_ */
+Index: linux-2.6.25.10/Documentation/gpiommc.txt
+===================================================================
+--- /dev/null	1970-01-01 00:00:00.000000000 +0000
++++ linux-2.6.25.10/Documentation/gpiommc.txt	2008-07-18 22:31:00.000000000 +0200
+@@ -0,0 +1,96 @@
++GPIOMMC - Driver for an MMC/SD card on a bitbanging GPIO SPI bus
++================================================================
++
++The gpiommc module hooks up the mmc_spi and spi_gpio modules for running an
++MMC or SD card on GPIO pins.
++
++Two interfaces for registering a new MMC/SD card device are provided.
++A static platform-device based mechanism and a dynamic sysfs based interface.
++
++
++Registering devices via platform-device
++=======================================
++
++The platform-device interface is used for registering MMC/SD devices that are
++part of the hardware platform. This is most useful only for embedded machines
++with MMC/SD devices statically connected to the platform GPIO bus.
++
++The data structures are declared in <linux/mmc/gpiommc.h>
++
++To register a new device, define an instance of struct gpiommc_platform_data.
++This structure holds any information about how the device is hooked up to the
++GPIO pins and what hardware modes the device supports. See the docbook-style
++documentation in the header file for more information on the struct fields.
++
++Then allocate a new instance of a platform device by doing:
++
++	pdev = platform_device_alloc(GPIOMMC_PLATDEV_NAME, gpiommc_next_id());
++
++This will allocate the platform device data structures and hook it up to the
++gpiommc driver.
++Then add the gpiommc_platform_data to the platform device.
++
++	err = platform_device_add_data(pdev, pdata, sizeof(struct gpiommc_platform_data));
++
++You may free the local instance of struct gpiommc_platform_data now.
++Now simply register the platform device.
++
++	err = platform_device_add(pdev);
++
++Done. The gpiommc probe routine should be called and you should see a dmesg
++message for the added device.
++
++
++Registering devices via sysfs
++=============================
++
++MMC/SD cards connected via GPIO often are a pretty dynamic thing. For example
++selfmade hacks for soldering an MMC/SD card to standard GPIO pins on embedded
++hardware are a common situation.
++So we provide a dynamic interface to conveniently handle adding and removing
++devices from userspace, without the need to recompile the kernel.
++
++There are two sysfs files responsible for that:
++export ADD=/sys/bus/platform/drivers/gpiommc/add
++export REMOVE=/sys/bus/platform/drivers/gpiommc/remove
++
++To add a new device, simply echo the configuration string to the "add" file.
++The config string is composed out of the following elements:
++
++DEVNAME DIpin DOpin CLKpin CSpin SPIMODE MAXBUSSPEED NO_SPI_DELAY CSACTIVELOW
++
++DEVNAME is a unique name string for the device.
++DIpin is the SPI DI GPIO pin.
++DOpin is the SPI DO GPIO pin.
++CLKpin is the SPI CLOCK GPIO pin.
++CSpin is the SPI CHIPSELECT GPIO pin.
++SPIMODE is the hardware mode the device will run at. Can be 0-3.
++MAXBUSSPEED is the maximum bus speed in Hertz.
++NO_SPI_DELAY can be 1 or 0. If it is 1, then the lowlevel SPI delay
++will not be performed. This is not standards compliant, but may be required
++to gain reasonable speeds on embedded hardware.
++CSACTIVELOW can be 1 or 0. If it is 1, the chip is considered to be selected, if CS
++is at a logical 0.
++
++Note that the elements SPIMODE, MAXBUSSPEED and NO_SPI_DELAY are optional
++and can be omitted.
++SPIMODE will default to 0.
++MAXBUSSSPEED will default to 5Mhz.
++NO_SPI_DELAY will default to 0.
++CSACTIVELOW will default to 1.
++
++Example:
++
++	echo -n "my_device 5 4 3 7 0 1000000 1" > $ADD
++
++This will add a new device called "my_device" with the GPIO pins assigned as
++DI=5, DO=4, CLK=3, CS=7
++The hardware mode will be SPI_MODE_0.
++The maximum bus speed will be 1000000 Hz (1Mhz)
++And the explicit SPI delay at the lowlevel bitbang loop will be switched off.
++
++To remove a device, simply echo the device name string to the "remove" file.
++
++Example:
++
++	echo -n "my_device" > $REMOVE
+Index: linux-2.6.25.10/MAINTAINERS
+===================================================================
+--- linux-2.6.25.10.orig/MAINTAINERS	2008-07-18 22:30:41.000000000 +0200
++++ linux-2.6.25.10/MAINTAINERS	2008-07-18 22:31:00.000000000 +0200
+@@ -1736,6 +1736,11 @@ L:	gigaset307x-common@lists.sourceforge.
+ W:	http://gigaset307x.sourceforge.net/
+ S:	Maintained
+ 
++GPIOMMC DRIVER
++P:	Michael Buesch
++M:	mb@bu3sch.de
++S:	Maintained
++
+ HARDWARE MONITORING
+ P:	Mark M. Hoffman
+ M:	mhoffman@lightlink.com