mirror/openwrt
1
0
Fork 0
mirror of https://git.openwrt.org/openwrt/openwrt.git synced 2024-10-01 00:21:51 +02:00
Code Issues

Update GPIO-based MMC driver

Browse Source 
SVN-Revision: 11864
This commit is contained in:
Michael Büsch 2008-07-18 20:53:08 +00:00
parent 9d5543e8b9
commit f4b516ef34
8 changed files with 922 additions and 655 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
package/mmc_over_gpio/Makefile
View File

@ -4,8 +4,6 @@
# This is free software, licensed under the GNU General Public License v2.
# See /LICENSE for more information.
#XXX This package will go away once the stuff is merged into the kernel.
include $(TOPDIR)/rules.mk
include $(INCLUDE_DIR)/kernel.mk
@ -18,9 +16,10 @@ include $(INCLUDE_DIR)/package.mk
define KernelPackage/mmc-over-gpio
SUBMENU:=Other modules
DEPENDS:=@GPIO_SUPPORT +kmod-mmc-spi +kmod-spi-gpio
KCONFIG:=CONFIG_GPIOMMC
TITLE:=MMC/SD card over GPIO support
FILES:=$(PKG_BUILD_DIR)/mmc_over_spigpio.$(LINUX_KMOD_SUFFIX)
AUTOLOAD:=$(call AutoLoad,93,spi_gpio mmc_over_spigpio)
FILES:=$(LINUX_DIR)/drivers/mmc/host/gpiommc.$(LINUX_KMOD_SUFFIX)
AUTOLOAD:=$(call AutoLoad,93,spi_gpio gpiommc)
endef
define KernelPackage/mmc-over-gpio/description
@ -29,16 +28,9 @@ endef
define Build/Prepare
mkdir -p $(PKG_BUILD_DIR)
$(CP) ./src/* $(PKG_BUILD_DIR)/
endef
define Build/Compile
$(MAKE) -C "$(LINUX_DIR)" \
CROSS_COMPILE="$(TARGET_CROSS)" \
ARCH="$(LINUX_KARCH)" \
SUBDIRS="$(PKG_BUILD_DIR)" \
EXTRA_CFLAGS="$(BUILDFLAGS)" \
modules
endef
define KernelPackage/mmc-over-gpio/install

4
package/mmc_over_gpio/files/mmc_over_gpio.init
View File

@ -3,11 +3,11 @@
START=90
SYSFS="/sys"
SYSFS_DRIVERDIR="$SYSFS/bus/platform/drivers/spi-gpio-mmc"
SYSFS_DRIVERDIR="$SYSFS/bus/platform/drivers/gpiommc"
# add_device(name, DI_pin, DO_pin, CLK_pin, CS_pin, mode)
add_device() {
echo -n "$1" "$2","$3","$4","$5" "$6" > $SYSFS_DRIVERDIR/add
echo -n "$1" "$2" "$3" "$4" "$5" "$6" > $SYSFS_DRIVERDIR/add
}
# remove_device(name)

1
package/mmc_over_gpio/src/Makefile
View File

@ -1 +0,0 @@
obj-m += mmc_over_spigpio.o

339
package/mmc_over_gpio/src/mmc_over_spigpio.c
View File

@ -1,339 +0,0 @@
/*
* Driver for driving an MMC card over a bitbanging GPIO SPI bus.
*
* Copyright 2008 Michael Buesch <mb@bu3sch.de>
*
* Licensed under the GNU/GPL. See COPYING for details.
*/
#include <linux/platform_device.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/spi/spi_gpio.h>
/* This is the maximum speed in Hz */
#define GPIOMMC_MAXSPEED 5000000 /* Hz */
#define DRIVER_NAME "spi-gpio-mmc"
#define PFX DRIVER_NAME ": "
#define GPIOMMC_MAX_NAMELEN 15
#define GPIOMMC_MAX_NAMELEN_STR __stringify(GPIOMMC_MAX_NAMELEN)
struct gpiommc_pins {
unsigned int gpio_di; /* Card DI pin */
unsigned int gpio_do; /* Card DO pin */
unsigned int gpio_clk; /* Card CLK pin */
unsigned int gpio_cs; /* Card CS pin */
};
struct gpiommc_device {
char name[GPIOMMC_MAX_NAMELEN + 1];
struct platform_device *pdev;
struct platform_device *spi_pdev;
struct gpiommc_pins pins;
u8 mode; /* SPI_MODE_X */
struct spi_board_info boardinfo;
struct list_head list;
};
static LIST_HEAD(gpiommc_devices_list);
static DEFINE_MUTEX(gpiommc_mutex);
MODULE_DESCRIPTION("SPI-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;
/* Bind the SPI master to the MMC-SPI host driver. */
strlcpy(bi->modalias, "mmc_spi", sizeof(bi->modalias));
bi->max_speed_hz = GPIOMMC_MAXSPEED;
bi->bus_num = master->bus_num;
bi->mode = d->mode;
return 0;
}
static int gpiommc_probe(struct platform_device *pdev)
{
static int instance;
struct gpiommc_device *d = platform_get_drvdata(pdev);
struct spi_gpio_platform_data pdata;
int err = -ENOMEM;
d->spi_pdev = platform_device_alloc("spi-gpio", instance++);
if (!d->spi_pdev)
goto out;
memset(&pdata, 0, sizeof(pdata));
pdata.pin_clk = d->pins.gpio_clk;
pdata.pin_miso = d->pins.gpio_do;
pdata.pin_mosi = d->pins.gpio_di;
pdata.pin_cs = d->pins.gpio_cs;
pdata.cs_activelow = 1;
pdata.no_spi_delay = 1;
pdata.boardinfo_setup = gpiommc_boardinfo_setup;
pdata.boardinfo_setup_data = d;
err = platform_device_add_data(d->spi_pdev, &pdata, sizeof(pdata));
if (err)
goto err_free_pdev;
err = platform_device_register(d->spi_pdev);
if (err)
goto err_free_pdata;
printk(KERN_INFO PFX "MMC-Card \"%s\" "
"attached to GPIO pins %u,%u,%u,%u\n",
d->name, d->pins.gpio_di, d->pins.gpio_do,
d->pins.gpio_clk, d->pins.gpio_cs);
out:
return err;
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);
return err;
}
static int gpiommc_remove(struct platform_device *pdev)
{
struct gpiommc_device *d = platform_get_drvdata(pdev);
platform_device_unregister(d->spi_pdev);
printk(KERN_INFO PFX "MMC-Card \"%s\" removed\n", d->name);
return 0;
}
static void gpiommc_free(struct gpiommc_device *d)
{
kfree(d);
}
static struct gpiommc_device * gpiommc_alloc(struct platform_device *pdev,
const char *name,
const struct gpiommc_pins *pins,
u8 mode)
{
struct gpiommc_device *d;
d = kmalloc(sizeof(*d), GFP_KERNEL);
if (!d)
return NULL;
strcpy(d->name, name);
memcpy(&d->pins, pins, sizeof(d->pins));
d->mode = mode;
INIT_LIST_HEAD(&d->list);
return d;
}
/* List must be locked. */
static struct gpiommc_device * gpiommc_find_device(const char *name)
{
struct gpiommc_device *d;
list_for_each_entry(d, &gpiommc_devices_list, list) {
if (strcmp(d->name, name) == 0)
return d;
}
return NULL;
}
static void gpiommc_do_destroy_device(struct gpiommc_device *d)
{
list_del(&d->list);
platform_device_unregister(d->pdev);
gpiommc_free(d);
}
static int gpiommc_destroy_device(const char *name)
{
struct gpiommc_device *d;
int err = -ENODEV;
mutex_lock(&gpiommc_mutex);
d = gpiommc_find_device(name);
if (!d)
goto out_unlock;
gpiommc_do_destroy_device(d);
err = 0;
out_unlock:
mutex_unlock(&gpiommc_mutex);
return err;
}
static int gpiommc_create_device(const char *name,
const struct gpiommc_pins *pins,
u8 mode)
{
static int instance;
struct platform_device *pdev;
struct gpiommc_device *d;
int err;
mutex_lock(&gpiommc_mutex);
err = -EEXIST;
if (gpiommc_find_device(name))
goto out_unlock;
err = -ENOMEM;
pdev = platform_device_alloc(DRIVER_NAME, instance++);
if (!pdev)
goto out_unlock;
d = gpiommc_alloc(pdev, name, pins, mode);
if (!d)
goto err_free_pdev;
platform_set_drvdata(pdev, d);
d->pdev = pdev;
err = platform_device_register(pdev);
if (err)
goto err_free_mdev;
list_add(&d->list, &gpiommc_devices_list);
err = 0;
out_unlock:
mutex_unlock(&gpiommc_mutex);
return err;
err_free_mdev:
gpiommc_free(d);
err_free_pdev:
platform_device_put(pdev);
goto out_unlock;
}
static ssize_t gpiommc_add_show(struct device_driver *drv,
char *buf)
{
return snprintf(buf, PAGE_SIZE, "NAME DI_pin,DO_pin,CLK_pin,CS_pin [MODE]\n");
}
static ssize_t gpiommc_add_store(struct device_driver *drv,
const char *buf, size_t count)
{
int res, err;
char name[GPIOMMC_MAX_NAMELEN + 1];
struct gpiommc_pins pins;
unsigned int mode;
res = sscanf(buf, "%" GPIOMMC_MAX_NAMELEN_STR "s %u,%u,%u,%u %u",
name, &pins.gpio_di, &pins.gpio_do,
&pins.gpio_clk, &pins.gpio_cs, &mode);
if (res == 5)
mode = 0;
else if (res != 6)
return -EINVAL;
switch (mode) {
case 0:
mode = SPI_MODE_0;
break;
case 1:
mode = SPI_MODE_1;
break;
case 2:
mode = SPI_MODE_2;
break;
case 3:
mode = SPI_MODE_3;
break;
default:
return -EINVAL;
}
err = gpiommc_create_device(name, &pins, mode);
return err ? err : count;
}
static ssize_t gpiommc_remove_show(struct device_driver *drv,
char *buf)
{
return snprintf(buf, PAGE_SIZE, "write device-name to remove the device\n");
}
static ssize_t gpiommc_remove_store(struct device_driver *drv,
const char *buf, size_t count)
{
int err;
err = gpiommc_destroy_device(buf);
return err ? err : count;
}
static DRIVER_ATTR(add, 0600,
gpiommc_add_show, gpiommc_add_store);
static DRIVER_ATTR(remove, 0600,
gpiommc_remove_show, gpiommc_remove_store);
static struct platform_driver gpiommc_plat_driver = {
.probe = gpiommc_probe,
.remove = gpiommc_remove,
.driver = {
.name = DRIVER_NAME,
.owner = THIS_MODULE,
},
};
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_device *d, *tmp;
driver_remove_file(&gpiommc_plat_driver.driver,
&driver_attr_remove);
driver_remove_file(&gpiommc_plat_driver.driver,
&driver_attr_add);
mutex_lock(&gpiommc_mutex);
list_for_each_entry_safe(d, tmp, &gpiommc_devices_list, list)
gpiommc_do_destroy_device(d);
mutex_unlock(&gpiommc_mutex);
platform_driver_unregister(&gpiommc_plat_driver);
}
module_exit(gpiommc_modexit);

242
target/linux/generic-2.6/files-2.6.25/drivers/spi/spi_gpio.c
View File

@ -1,242 +0,0 @@
/*
* 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.h" //XXX
#include <asm/gpio.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 <linux/spi/spi_bitbang.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, 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, 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, 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, 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",
.owner = THIS_MODULE,
},
.probe = spi_gpio_probe,
.remove = __devexit_p(spi_gpio_remove),
};
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 bitbangling SPI driver");
MODULE_LICENSE("GPL v2");

53
target/linux/generic-2.6/files-2.6.25/include/linux/spi/spi_gpio.h
View File

@ -1,53 +0,0 @@
/*
* spi_gpio interface to platform code
*
* Copyright (c) 2008 Piotr Skamruk
*
* 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;
};
#endif /* _LINUX_SPI_SPI_GPIO */

370
target/linux/generic-2.6/patches-2.6.25/921-gpio_spi_driver.patch
View File

@ -1,20 +1,360 @@
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -100,6 +100,11 @@
Index: linux-2.6.25.10/include/linux/spi/spi_gpio.h
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.25.10/include/linux/spi/spi_gpio.h 2008-07-18 18:19:56.000000000 +0200
@@ -0,0 +1,67 @@
+/*
+ * 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 */
Index: linux-2.6.25.10/drivers/spi/spi_gpio.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.25.10/drivers/spi/spi_gpio.c 2008-07-18 18:19:56.000000000 +0200
@@ -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.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 <linux/spi/spi_bitbang.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, 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, 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, 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, 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");
Index: linux-2.6.25.10/drivers/spi/Kconfig
===================================================================
--- linux-2.6.25.10.orig/drivers/spi/Kconfig 2008-07-18 18:19:43.000000000 +0200
+++ linux-2.6.25.10/drivers/spi/Kconfig 2008-07-18 18:19:56.000000000 +0200
@@ -100,6 +100,19 @@ config SPI_BUTTERFLY
inexpensive battery powered microcontroller evaluation board.
This same cable can be used to flash new firmware.
+config SPI_GPIO
+ tristate "GPIO API based bitbanging SPI controller"
+ depends on SPI_MASTER && GENERIC_GPIO && EXPERIMENTAL
+ depends on SPI_MASTER && GENERIC_GPIO
+ select SPI_BITBANG
+ help
+ This is a platform driver that can be used for bitbanging
+ an SPI bus over GPIO pins.
+ Select this, if you have any SPI device that is connected via
+ GPIO pins.
+ The module will be called spi_gpio.
+
+ If unsure, say N.
+
config SPI_IMX
tristate "Freescale iMX SPI controller"
depends on SPI_MASTER && ARCH_IMX && EXPERIMENTAL
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -16,6 +16,7 @@
Index: linux-2.6.25.10/drivers/spi/Makefile
===================================================================
--- linux-2.6.25.10.orig/drivers/spi/Makefile 2008-07-18 18:19:43.000000000 +0200
+++ linux-2.6.25.10/drivers/spi/Makefile 2008-07-18 18:19:56.000000000 +0200
@@ -16,6 +16,7 @@ obj-$(CONFIG_SPI_BFIN) += spi_bfin5xx.
obj-$(CONFIG_SPI_BITBANG) += spi_bitbang.o
obj-$(CONFIG_SPI_AU1550) += au1550_spi.o
obj-$(CONFIG_SPI_BUTTERFLY) += spi_butterfly.o
@ -22,3 +362,19 @@
obj-$(CONFIG_SPI_IMX) += spi_imx.o
obj-$(CONFIG_SPI_LM70_LLP) += spi_lm70llp.o
obj-$(CONFIG_SPI_PXA2XX) += pxa2xx_spi.o
Index: linux-2.6.25.10/MAINTAINERS
===================================================================
--- linux-2.6.25.10.orig/MAINTAINERS 2008-07-03 05:46:47.000000000 +0200
+++ linux-2.6.25.10/MAINTAINERS 2008-07-18 18:20:28.000000000 +0200
@@ -3685,6 +3685,11 @@ M: dbrownell@users.sourceforge.net
L: spi-devel-general@lists.sourceforge.net
S: Maintained
+SPI GPIO MASTER DRIVER
+P: Michael Buesch
+M: mb@bu3sch.de
+S: Maintained
+
STABLE BRANCH:
P: Greg Kroah-Hartman
M: greg@kroah.com

554
target/linux/generic-2.6/patches-2.6.25/922-gpiommc.patch Normal file
View File

@ -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