update to 2.6.27.6

[openwrt.git] / target / linux / generic-2.6 / patches-2.6.25 / 922-gpiommc.patch

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
index 8253202..b775a0e 100644 (file)
--- 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
@@ -1,14 +1,10 @@
-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 @@
+--- /dev/null
++++ b/drivers/mmc/host/gpiommc.c
+@@ -0,0 +1,605 @@

 +/*
 + * Driver an MMC/SD card on a bitbanging GPIO SPI bus.
 + * This module hooks up the mmc_spi and spi_gpio modules and also
 +/*
 + * 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>
++ * provides a configfs interface.

 + *
 + * Licensed under the GNU/GPL. See COPYING for details.
 + */
 + *
 + * Licensed under the GNU/GPL. See COPYING for details.
 + */


@@ -18,10 +14,13 @@ Index: linux-2.6.25.10/drivers/mmc/host/gpiommc.c
 +#include <linux/list.h>
 +#include <linux/mutex.h>
 +#include <linux/spi/spi_gpio.h>
 +#include <linux/list.h>
 +#include <linux/mutex.h>
 +#include <linux/spi/spi_gpio.h>

++#include <linux/configfs.h>
++#include <linux/gpio.h>
++#include <asm/atomic.h>

 +
 +
 +#define PFX                           "gpio-mmc: "
 +
 +
 +#define PFX                           "gpio-mmc: "

-+#define GPIOMMC_MAX_NAMELEN_STR               __stringify(GPIOMMC_MAX_NAMELEN)
++

 +
 +struct gpiommc_device {
 +      struct platform_device *pdev;
 +
 +struct gpiommc_device {
 +      struct platform_device *pdev;


@@ -31,7 +30,6 @@ Index: linux-2.6.25.10/drivers/mmc/host/gpiommc.c
 +
 +
 +MODULE_DESCRIPTION("GPIO based MMC driver");
 +
 +
 +MODULE_DESCRIPTION("GPIO based MMC driver");

-+MODULE_AUTHOR("Michael Buesch");

 +MODULE_LICENSE("GPL");
 +
 +
 +MODULE_LICENSE("GPL");
 +
 +


@@ -63,6 +61,14 @@ Index: linux-2.6.25.10/drivers/mmc/host/gpiommc.c
 +      if (!mmc_pdata)
 +              goto error;
 +
 +      if (!mmc_pdata)
 +              goto error;
 +

++#ifdef CONFIG_MMC_SPI_MODULE
++      err = request_module("mmc_spi");
++      if (err) {
++              printk(KERN_WARNING PFX
++                     "Failed to request mmc_spi module.\n");
++      }
++#endif /* CONFIG_MMC_SPI_MODULE */
++

 +      /* Allocate the GPIO-MMC device */
 +      err = -ENOMEM;
 +      d = kzalloc(sizeof(*d), GFP_KERNEL);
 +      /* Allocate the GPIO-MMC device */
 +      err = -ENOMEM;
 +      d = kzalloc(sizeof(*d), GFP_KERNEL);


@@ -121,152 +127,438 @@ Index: linux-2.6.25.10/drivers/mmc/host/gpiommc.c
 +      struct gpiommc_platform_data *pdata = d->pdev->dev.platform_data;
 +
 +      platform_device_unregister(d->spi_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);
++      printk(KERN_INFO PFX "GPIO based MMC-Card \"%s\" removed\n",
++             pdata->name);

 +      platform_device_put(d->spi_pdev);
 +
 +      return 0;
 +}
 +
 +      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 */
++#ifdef CONFIG_GPIOMMC_CONFIGFS

 +
 +

-+      /* The platform device that we allocated. */
++/* A device that was created through configfs */
++struct gpiommc_configfs_device {
++      struct config_item item;
++      /* The platform device, after registration. */

 +      struct platform_device *pdev;
 +      struct platform_device *pdev;

-+      /* gpiommc_sysfs_list */
-+      struct list_head list;
++      /* The configuration */
++      struct gpiommc_platform_data pdata;

 +};
 +
 +};
 +

-+static LIST_HEAD(gpiommc_sysfs_list);
-+static DEFINE_MUTEX(gpiommc_sysfs_mutex);
++#define GPIO_INVALID  -1

 +
 +

-+static struct gpiommc_sysfs_platform_data *gpiommc_sysfs_find_dev(const char *name)
++static inline bool gpiommc_is_registered(struct gpiommc_configfs_device *dev)

 +{
 +{

-+      struct gpiommc_sysfs_platform_data *pdata;
++      return (dev->pdev != NULL);
++}

 +
 +

-+      list_for_each_entry(pdata, &gpiommc_sysfs_list, list) {
-+              if (strcmp(pdata->p.name, name) == 0)
-+                      return pdata;
-+      }
++static inline struct gpiommc_configfs_device *ci_to_gpiommc(struct config_item *item)
++{
++      return item ? container_of(item, struct gpiommc_configfs_device, item) : NULL;
++}

 +
 +

-+      return NULL;
++static struct configfs_attribute gpiommc_attr_DI = {
++      .ca_owner = THIS_MODULE,
++      .ca_name = "gpio_data_in",
++      .ca_mode = S_IRUGO | S_IWUSR,
++};
++
++static struct configfs_attribute gpiommc_attr_DO = {
++      .ca_owner = THIS_MODULE,
++      .ca_name = "gpio_data_out",
++      .ca_mode = S_IRUGO | S_IWUSR,
++};
++
++static struct configfs_attribute gpiommc_attr_CLK = {
++      .ca_owner = THIS_MODULE,
++      .ca_name = "gpio_clock",
++      .ca_mode = S_IRUGO | S_IWUSR,
++};
++
++static struct configfs_attribute gpiommc_attr_CS = {
++      .ca_owner = THIS_MODULE,
++      .ca_name = "gpio_chipselect",
++      .ca_mode = S_IRUGO | S_IWUSR,
++};
++
++static struct configfs_attribute gpiommc_attr_CS_activelow = {
++      .ca_owner = THIS_MODULE,
++      .ca_name = "gpio_chipselect_activelow",
++      .ca_mode = S_IRUGO | S_IWUSR,
++};
++
++static struct configfs_attribute gpiommc_attr_spimode = {
++      .ca_owner = THIS_MODULE,
++      .ca_name = "spi_mode",
++      .ca_mode = S_IRUGO | S_IWUSR,
++};
++
++static struct configfs_attribute gpiommc_attr_spidelay = {
++      .ca_owner = THIS_MODULE,
++      .ca_name = "spi_delay",
++      .ca_mode = S_IRUGO | S_IWUSR,
++};
++
++static struct configfs_attribute gpiommc_attr_max_bus_speed = {
++      .ca_owner = THIS_MODULE,
++      .ca_name = "max_bus_speed",
++      .ca_mode = S_IRUGO | S_IWUSR,
++};
++
++static struct configfs_attribute gpiommc_attr_register = {
++      .ca_owner = THIS_MODULE,
++      .ca_name = "register",
++      .ca_mode = S_IRUGO | S_IWUSR,
++};
++
++static struct configfs_attribute *gpiommc_config_attrs[] = {
++      &gpiommc_attr_DI,
++      &gpiommc_attr_DO,
++      &gpiommc_attr_CLK,
++      &gpiommc_attr_CS,
++      &gpiommc_attr_CS_activelow,
++      &gpiommc_attr_spimode,
++      &gpiommc_attr_spidelay,
++      &gpiommc_attr_max_bus_speed,
++      &gpiommc_attr_register,
++      NULL,
++};
++
++static ssize_t gpiommc_config_attr_show(struct config_item *item,
++                                      struct configfs_attribute *attr,
++                                      char *page)
++{
++      struct gpiommc_configfs_device *dev = ci_to_gpiommc(item);
++      ssize_t count = 0;
++      unsigned int gpio;
++      int err = 0;
++
++      if (attr == &gpiommc_attr_DI) {
++              gpio = dev->pdata.pins.gpio_di;
++              if (gpio == GPIO_INVALID)
++                      count = snprintf(page, PAGE_SIZE, "not configured\n");
++              else
++                      count = snprintf(page, PAGE_SIZE, "%u\n", gpio);
++              goto out;
++      }
++      if (attr == &gpiommc_attr_DO) {
++              gpio = dev->pdata.pins.gpio_do;
++              if (gpio == GPIO_INVALID)
++                      count = snprintf(page, PAGE_SIZE, "not configured\n");
++              else
++                      count = snprintf(page, PAGE_SIZE, "%u\n", gpio);
++              goto out;
++      }
++      if (attr == &gpiommc_attr_CLK) {
++              gpio = dev->pdata.pins.gpio_clk;
++              if (gpio == GPIO_INVALID)
++                      count = snprintf(page, PAGE_SIZE, "not configured\n");
++              else
++                      count = snprintf(page, PAGE_SIZE, "%u\n", gpio);
++              goto out;
++      }
++      if (attr == &gpiommc_attr_CS) {
++              gpio = dev->pdata.pins.gpio_cs;
++              if (gpio == GPIO_INVALID)
++                      count = snprintf(page, PAGE_SIZE, "not configured\n");
++              else
++                      count = snprintf(page, PAGE_SIZE, "%u\n", gpio);
++              goto out;
++      }
++      if (attr == &gpiommc_attr_CS_activelow) {
++              count = snprintf(page, PAGE_SIZE, "%u\n",
++                               dev->pdata.pins.cs_activelow);
++              goto out;
++      }
++      if (attr == &gpiommc_attr_spimode) {
++              count = snprintf(page, PAGE_SIZE, "%u\n",
++                               dev->pdata.mode);
++              goto out;
++      }
++      if (attr == &gpiommc_attr_spidelay) {
++              count = snprintf(page, PAGE_SIZE, "%u\n",
++                               !dev->pdata.no_spi_delay);
++              goto out;
++      }
++      if (attr == &gpiommc_attr_max_bus_speed) {
++              count = snprintf(page, PAGE_SIZE, "%u\n",
++                               dev->pdata.max_bus_speed);
++              goto out;
++      }
++      if (attr == &gpiommc_attr_register) {
++              count = snprintf(page, PAGE_SIZE, "%u\n",
++                               gpiommc_is_registered(dev));
++              goto out;
++      }
++      WARN_ON(1);
++      err = -ENOSYS;
++out:
++      return err ? err : count;

 +}
 +
 +}
 +

-+static ssize_t gpiommc_add_store(struct device_driver *drv,
-+                               const char *buf, size_t count)
++static int gpiommc_do_register(struct gpiommc_configfs_device *dev,
++                             const char *name)

 +{
 +{

-+      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 */
++      int err;
++
++      if (gpiommc_is_registered(dev))
++              return 0;
++
++      if (!gpio_is_valid(dev->pdata.pins.gpio_di) ||
++          !gpio_is_valid(dev->pdata.pins.gpio_do) ||
++          !gpio_is_valid(dev->pdata.pins.gpio_clk) ||
++          !gpio_is_valid(dev->pdata.pins.gpio_cs)) {
++              printk(KERN_ERR PFX
++                     "configfs: Invalid GPIO pin number(s)\n");
++              return -EINVAL;

 +      }
 +
 +      }
 +

-+      err = -EEXIST;
-+      if (gpiommc_sysfs_find_dev(pdata->p.name))
-+              goto out;
++      strlcpy(dev->pdata.name, name,
++              sizeof(dev->pdata.name));
++
++      dev->pdev = platform_device_alloc(GPIOMMC_PLATDEV_NAME,
++                                        gpiommc_next_id());
++      if (!dev->pdev)
++              return -ENOMEM;
++      err = platform_device_add_data(dev->pdev, &dev->pdata,
++                                     sizeof(dev->pdata));
++      if (err) {
++              platform_device_put(dev->pdev);
++              return err;
++      }
++      err = platform_device_add(dev->pdev);
++      if (err) {
++              platform_device_put(dev->pdev);
++              return err;
++      }

 +
 +

-+      err = -ENOMEM;
-+      pdev = platform_device_alloc(GPIOMMC_PLATDEV_NAME, gpiommc_next_id());
-+      if (!pdev)
-+              goto out;
++      return 0;
++}

 +
 +

-+      err = platform_device_add_data(pdev, pdata, sizeof(*pdata));
-+      if (err)
-+              goto err_free_pdev;
-+      pdata = pdev->dev.platform_data;
++static void gpiommc_do_unregister(struct gpiommc_configfs_device *dev)
++{
++      if (!gpiommc_is_registered(dev))
++              return;

 +
 +

-+      err = platform_device_add(pdev);
-+      if (err)
-+              goto err_free_pdev;
++      platform_device_unregister(dev->pdev);
++      dev->pdev = NULL;
++}

 +
 +

-+      pdata->pdev = pdev;
-+      INIT_LIST_HEAD(&pdata->list);
-+      list_add(&pdata->list, &gpiommc_sysfs_list);
++static ssize_t gpiommc_config_attr_store(struct config_item *item,
++                                       struct configfs_attribute *attr,
++                                       const char *page, size_t count)
++{
++      struct gpiommc_configfs_device *dev = ci_to_gpiommc(item);
++      int err = -EINVAL;
++      unsigned long data;
++
++      if (attr == &gpiommc_attr_register) {
++              err = strict_strtoul(page, 10, &data);
++              if (err)
++                      goto out;
++              err = -EINVAL;
++              if (data == 1)
++                      err = gpiommc_do_register(dev, item->ci_name);
++              if (data == 0) {
++                      gpiommc_do_unregister(dev);
++                      err = 0;
++              }
++              goto out;
++      }

 +
 +

-+      err = 0;
-+out:
-+      mutex_unlock(&gpiommc_sysfs_mutex);
++      if (gpiommc_is_registered(dev)) {
++              /* The rest of the config parameters can only be set
++               * as long as the device is not registered, yet. */
++              err = -EBUSY;
++              goto out;
++      }

 +
 +

++      if (attr == &gpiommc_attr_DI) {
++              err = strict_strtoul(page, 10, &data);
++              if (err)
++                      goto out;
++              err = -EINVAL;
++              if (!gpio_is_valid(data))
++                      goto out;
++              dev->pdata.pins.gpio_di = data;
++              err = 0;
++              goto out;
++      }
++      if (attr == &gpiommc_attr_DO) {
++              err = strict_strtoul(page, 10, &data);
++              if (err)
++                      goto out;
++              err = -EINVAL;
++              if (!gpio_is_valid(data))
++                      goto out;
++              dev->pdata.pins.gpio_do = data;
++              err = 0;
++              goto out;
++      }
++      if (attr == &gpiommc_attr_CLK) {
++              err = strict_strtoul(page, 10, &data);
++              if (err)
++                      goto out;
++              err = -EINVAL;
++              if (!gpio_is_valid(data))
++                      goto out;
++              dev->pdata.pins.gpio_clk = data;
++              err = 0;
++              goto out;
++      }
++      if (attr == &gpiommc_attr_CS) {
++              err = strict_strtoul(page, 10, &data);
++              if (err)
++                      goto out;
++              err = -EINVAL;
++              if (!gpio_is_valid(data))
++                      goto out;
++              dev->pdata.pins.gpio_cs = data;
++              err = 0;
++              goto out;
++      }
++      if (attr == &gpiommc_attr_CS_activelow) {
++              err = strict_strtoul(page, 10, &data);
++              if (err)
++                      goto out;
++              err = -EINVAL;
++              if (data != 0 && data != 1)
++                      goto out;
++              dev->pdata.pins.cs_activelow = data;
++              err = 0;
++              goto out;
++      }
++      if (attr == &gpiommc_attr_spimode) {
++              err = strict_strtoul(page, 10, &data);
++              if (err)
++                      goto out;
++              err = -EINVAL;
++              switch (data) {
++              case 0:
++                      dev->pdata.mode = SPI_MODE_0;
++                      break;
++              case 1:
++                      dev->pdata.mode = SPI_MODE_1;
++                      break;
++              case 2:
++                      dev->pdata.mode = SPI_MODE_2;
++                      break;
++              case 3:
++                      dev->pdata.mode = SPI_MODE_3;
++                      break;
++              default:
++                      goto out;
++              }
++              err = 0;
++              goto out;
++      }
++      if (attr == &gpiommc_attr_spidelay) {
++              err = strict_strtoul(page, 10, &data);
++              if (err)
++                      goto out;
++              err = -EINVAL;
++              if (data != 0 && data != 1)
++                      goto out;
++              dev->pdata.no_spi_delay = !data;
++              err = 0;
++              goto out;
++      }
++      if (attr == &gpiommc_attr_max_bus_speed) {
++              err = strict_strtoul(page, 10, &data);
++              if (err)
++                      goto out;
++              err = -EINVAL;
++              if (data > UINT_MAX)
++                      goto out;
++              dev->pdata.max_bus_speed = data;
++              err = 0;
++              goto out;
++      }
++      WARN_ON(1);
++      err = -ENOSYS;
++out:

 +      return err ? err : count;
 +      return err ? err : count;

++}

 +
 +

-+err_free_pdev:
-+      platform_device_put(pdev);
-+      goto out;
++static void gpiommc_config_item_release(struct config_item *item)
++{
++      struct gpiommc_configfs_device *dev = ci_to_gpiommc(item);
++
++      kfree(dev);

 +}
 +
 +}
 +

-+static ssize_t gpiommc_remove_store(struct device_driver *drv,
-+                                  const char *buf, size_t count)
++static struct configfs_item_operations gpiommc_config_item_ops = {
++      .release                = gpiommc_config_item_release,
++      .show_attribute         = gpiommc_config_attr_show,
++      .store_attribute        = gpiommc_config_attr_store,
++};
++
++static struct config_item_type gpiommc_dev_ci_type = {
++      .ct_item_ops    = &gpiommc_config_item_ops,
++      .ct_attrs       = gpiommc_config_attrs,
++      .ct_owner       = THIS_MODULE,
++};
++
++static struct config_item *gpiommc_make_item(struct config_group *group,
++                                           const char *name)

 +{
 +{

-+      struct gpiommc_sysfs_platform_data *pdata;
-+      int err;
++      struct gpiommc_configfs_device *dev;

 +
 +

-+      mutex_lock(&gpiommc_sysfs_mutex);
++      if (strlen(name) > GPIOMMC_MAX_NAMELEN) {
++              printk(KERN_ERR PFX "configfs: device name too long\n");
++              return NULL;
++      }

 +
 +

-+      err = -ENODEV;
-+      pdata = gpiommc_sysfs_find_dev(buf);
-+      if (!pdata)
-+              goto out;
++      dev = kzalloc(sizeof(*dev), GFP_KERNEL);
++      if (!dev)
++              return NULL;

 +
 +

-+      list_del(&pdata->list);
-+      platform_device_unregister(pdata->pdev);
++      config_item_init_type_name(&dev->item, name,
++                                 &gpiommc_dev_ci_type);

 +
 +

-+out:
-+      mutex_unlock(&gpiommc_sysfs_mutex);
++      /* Assign default configuration */
++      dev->pdata.pins.gpio_di = GPIO_INVALID;
++      dev->pdata.pins.gpio_do = GPIO_INVALID;
++      dev->pdata.pins.gpio_clk = GPIO_INVALID;
++      dev->pdata.pins.gpio_cs = GPIO_INVALID;
++      dev->pdata.pins.cs_activelow = 1;
++      dev->pdata.mode = SPI_MODE_0;
++      dev->pdata.no_spi_delay = 0;
++      dev->pdata.max_bus_speed = 5000000; /* 5 MHz */

 +
 +

-+      return err ? err : count;
++      return &(dev->item);

 +}
 +
 +}
 +

-+static DRIVER_ATTR(add, 0200,
-+                 NULL, gpiommc_add_store);
-+static DRIVER_ATTR(remove, 0200,
-+                 NULL, gpiommc_remove_store);
++static void gpiommc_drop_item(struct config_group *group,
++                            struct config_item *item)
++{
++      struct gpiommc_configfs_device *dev = ci_to_gpiommc(item);
++
++      gpiommc_do_unregister(dev);
++      kfree(dev);
++}
++
++static struct configfs_group_operations gpiommc_ct_group_ops = {
++      .make_item      = gpiommc_make_item,
++      .drop_item      = gpiommc_drop_item,
++};
++
++static struct config_item_type gpiommc_ci_type = {
++      .ct_group_ops   = &gpiommc_ct_group_ops,
++      .ct_owner       = THIS_MODULE,
++};
++
++static struct configfs_subsystem gpiommc_subsys = {
++      .su_group = {
++              .cg_item = {
++                      .ci_namebuf = GPIOMMC_PLATDEV_NAME,
++                      .ci_type = &gpiommc_ci_type,
++              },
++      },
++      .su_mutex = __MUTEX_INITIALIZER(gpiommc_subsys.su_mutex),
++};
++
++#endif /* CONFIG_GPIOMMC_CONFIGFS */

 +
 +static struct platform_driver gpiommc_plat_driver = {
 +      .probe  = gpiommc_probe,
 +
 +static struct platform_driver gpiommc_plat_driver = {
 +      .probe  = gpiommc_probe,


@@ -292,50 +584,31 @@ Index: linux-2.6.25.10/drivers/mmc/host/gpiommc.c
 +      err = platform_driver_register(&gpiommc_plat_driver);
 +      if (err)
 +              return 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;
++#ifdef CONFIG_GPIOMMC_CONFIGFS
++      config_group_init(&gpiommc_subsys.su_group);
++      err = configfs_register_subsystem(&gpiommc_subsys);
++      if (err) {
++              platform_driver_unregister(&gpiommc_plat_driver);
++              return err;
++      }
++#endif /* CONFIG_GPIOMMC_CONFIGFS */

 +
 +

-+err_remove_add:
-+      driver_remove_file(&gpiommc_plat_driver.driver,
-+                         &driver_attr_add);
-+err_drv_unreg:
-+      platform_driver_unregister(&gpiommc_plat_driver);
-+      return err;
++      return 0;

 +}
 +module_init(gpiommc_modinit);
 +
 +static void __exit gpiommc_modexit(void)
 +{
 +}
 +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);
-+
++#ifdef CONFIG_GPIOMMC_CONFIGFS
++      configfs_unregister_subsystem(&gpiommc_subsys);
++#endif

 +      platform_driver_unregister(&gpiommc_plat_driver);
 +}
 +module_exit(gpiommc_modexit);
 +      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
+--- a/drivers/mmc/host/Kconfig
++++ b/drivers/mmc/host/Kconfig
+@@ -130,3 +130,27 @@ config MMC_SPI

  
          If unsure, or if your system has no SPI master driver, say N.
  
  
          If unsure, or if your system has no SPI master driver, say N.
  


@@ -347,8 +620,8 @@ Index: linux-2.6.25.10/drivers/mmc/host/Kconfig
 +        MMC/SD cards can be used on a GPIO based bus by bitbanging
 +        the SPI protocol in software.
 +
 +        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
++        This driver provides a configfs interface to dynamically create
++        and destroy GPIO-based MMC/SD card devices. It also provides

 +        a platform device interface API.
 +        See Documentation/gpiommc.txt for details.
 +
 +        a platform device interface API.
 +        See Documentation/gpiommc.txt for details.
 +


@@ -356,28 +629,27 @@ Index: linux-2.6.25.10/drivers/mmc/host/Kconfig
 +
 +        If unsure, say N.
 +
 +
 +        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-$(CONFIG_MMC_AT91)               += at91_mci.o
++config GPIOMMC_CONFIGFS
++      bool
++      depends on GPIOMMC && CONFIGFS_FS
++      default y
++      help
++        This option automatically enables configfs support for gpiommc
++        if configfs is available.
+--- a/drivers/mmc/host/Makefile
++++ b/drivers/mmc/host/Makefile
+@@ -17,4 +17,4 @@ obj-$(CONFIG_MMC_OMAP)               += omap.o
+ obj-$(CONFIG_MMC_AT91)                += at91_mci.o

  obj-$(CONFIG_MMC_TIFM_SD)     += tifm_sd.o
  obj-$(CONFIG_MMC_SPI)         += mmc_spi.o
  obj-$(CONFIG_MMC_TIFM_SD)     += tifm_sd.o
  obj-$(CONFIG_MMC_SPI)         += mmc_spi.o

- 
+-

 +obj-$(CONFIG_GPIOMMC)         += gpiommc.o
 +obj-$(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 @@
+--- /dev/null
++++ b/include/linux/mmc/gpiommc.h
+@@ -0,0 +1,69 @@

 +/*
 + * Device driver for MMC/SD cards driven over a GPIO bus.
 + *
 +/*
 + * 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_
 + * Licensed under the GNU/GPL version 2.
 + */
 +#ifndef LINUX_GPIOMMC_H_


@@ -387,8 +659,11 @@ Index: linux-2.6.25.10/include/linux/mmc/gpiommc.h
 +
 +
 +#define GPIOMMC_MAX_NAMELEN           15
 +
 +
 +#define GPIOMMC_MAX_NAMELEN           15

++#define GPIOMMC_MAX_NAMELEN_STR               __stringify(GPIOMMC_MAX_NAMELEN)

 +
 +

-+/** struct gpiommc_pins - Hardware pin assignments
++/**
++ * 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_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


@@ -403,7 +678,9 @@ Index: linux-2.6.25.10/include/linux/mmc/gpiommc.h
 +      bool cs_activelow;
 +};
 +
 +      bool cs_activelow;
 +};
 +

-+/** struct gpiommc_platform_data - Platform data for a MMC-over-SPI-GPIO device.
++/**
++ * 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,
 + * @name: The unique name string of the device.
 + * @pins: The hardware pin assignments.
 + * @mode: The hardware mode. This is either SPI_MODE_0,


@@ -421,13 +698,17 @@ Index: linux-2.6.25.10/include/linux/mmc/gpiommc.h
 +      unsigned int max_bus_speed;
 +};
 +
 +      unsigned int max_bus_speed;
 +};
 +

-+/** GPIOMMC_PLATDEV_NAME - The platform device name string.
++/**
++ * 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"
 +
 + * 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.
++/**
++ * 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.
 + * 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.


@@ -435,19 +716,17 @@ Index: linux-2.6.25.10/include/linux/mmc/gpiommc.h
 +int gpiommc_next_id(void);
 +
 +#endif /* LINUX_GPIOMMC_H_ */
 +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 @@
+--- /dev/null
++++ b/Documentation/gpiommc.txt
+@@ -0,0 +1,97 @@

 +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.
 +
 +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.
++Two interfaces for registering a new MMC/SD card device are provided:
++A static platform-device based mechanism and a dynamic configfs based interface.

 +
 +
 +Registering devices via platform-device
 +
 +
 +Registering devices via platform-device


@@ -457,7 +736,7 @@ Index: linux-2.6.25.10/Documentation/gpiommc.txt
 +part of the hardware platform. This is most useful only for embedded machines
 +with MMC/SD devices statically connected to the platform GPIO bus.
 +
 +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>
++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
 +
 +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


@@ -474,81 +753,66 @@ Index: linux-2.6.25.10/Documentation/gpiommc.txt
 +
 +      err = platform_device_add_data(pdev, pdata, sizeof(struct gpiommc_platform_data));
 +
 +
 +      err = platform_device_add_data(pdev, pdata, sizeof(struct gpiommc_platform_data));
 +

-+You may free the local instance of struct gpiommc_platform_data now.
++You may free the local instance of struct gpiommc_platform_data now. (So the
++struct may be allocated on the stack, too).

 +Now simply register the platform device.
 +
 +      err = platform_device_add(pdev);
 +
 +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.
++Done. The gpiommc probe routine will be invoked now and you should see a kernel
++log message for the added device.

 +
 +
 +
 +

-+Registering devices via sysfs
-+=============================
++Registering devices via configfs
++================================

 +
 +

-+MMC/SD cards connected via GPIO often are a pretty dynamic thing. For example
++MMC/SD cards connected via GPIO often are a pretty dynamic thing, as 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.
 +
 +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
++The "gpiommc" subdirectory at the configfs mountpoint is used for handling
++the dynamic configuration.
++
++To create a new device, it must first be allocated with mkdir.
++The following command will allocate a device named "my_mmc":
++      mkdir /config/gpiommc/my_mmc
++
++There are several configuration files available in the new
++/config/gpiommc/my_mmc/ directory:
++
++gpio_data_in                  = The SPI data-IN GPIO pin number.
++gpio_data_out                 = The SPI data-OUT GPIO pin number.
++gpio_clock                    = The SPI Clock GPIO pin number.
++gpio_chipselect                       = The SPI Chipselect GPIO pin number.
++gpio_chipselect_activelow     = Boolean. If 0, Chipselect is active-HIGH.
++                                If 1, Chipselect is active-LOW.
++spi_mode                      = The SPI data mode. Can be 0-3.
++spi_delay                     = Enable all delays in the lowlevel bitbanging.
++max_bus_speed                 = The maximum SPI bus speed. In Hertz.
++
++register                      = Not a configuration parameter.
++                                Used to register the configured card
++                                with the kernel.
++
++The device must first get configured and then registered by writing "1" to
++the "register" file.
++The configuration parameters "gpio_data_in", "gpio_data_out", "gpio_clock"
++and "gpio_chipselect" are essential and _must_ be configured before writing
++"1" to the "register" file. The registration will fail, otherwise.
++
++The default values for the other parameters are:
++gpio_chipselect_activelow     = 1             (CS active-LOW)
++spi_mode                      = 0             (SPI_MODE_0)
++spi_delay                     = 1             (enabled)
++max_bus_speed                 = 5000000       (5 Mhz)
++
++Configuration values can not be changed after registration. To unregister
++the device, write a "0" to the "register" file. The configuration can be
++changed again after unregistering.
++
++To completely remove the device, simply rmdir the directory
++(/config/gpiommc/my_mmc in this example).
++There's no need to first unregister the device before removing it. That will
++be done automatically.