+++ /dev/null
---- /dev/null
-+++ b/drivers/mmc/host/gpiommc.c
-@@ -0,0 +1,608 @@
-+/*
-+ * 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 configfs 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_old.h>
-+#include <linux/configfs.h>
-+#include <linux/gpio.h>
-+#include <asm/atomic.h>
-+
-+
-+#define PFX "gpio-mmc: "
-+
-+
-+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;
-+
-+#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);
-+ 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;
-+}
-+
-+#ifdef CONFIG_GPIOMMC_CONFIGFS
-+
-+/* A device that was created through configfs */
-+struct gpiommc_configfs_device {
-+ struct config_item item;
-+ /* The platform device, after registration. */
-+ struct platform_device *pdev;
-+ /* The configuration */
-+ struct gpiommc_platform_data pdata;
-+};
-+
-+#define GPIO_INVALID -1
-+
-+static inline bool gpiommc_is_registered(struct gpiommc_configfs_device *dev)
-+{
-+ return (dev->pdev != NULL);
-+}
-+
-+static inline struct gpiommc_configfs_device *ci_to_gpiommc(struct config_item *item)
-+{
-+ return item ? container_of(item, struct gpiommc_configfs_device, item) : 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 int gpiommc_do_register(struct gpiommc_configfs_device *dev,
-+ const char *name)
-+{
-+ 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;
-+ }
-+
-+ 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;
-+ }
-+
-+ return 0;
-+}
-+
-+static void gpiommc_do_unregister(struct gpiommc_configfs_device *dev)
-+{
-+ if (!gpiommc_is_registered(dev))
-+ return;
-+
-+ platform_device_unregister(dev->pdev);
-+ dev->pdev = NULL;
-+}
-+
-+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;
-+ }
-+
-+ 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;
-+}
-+
-+static void gpiommc_config_item_release(struct config_item *item)
-+{
-+ struct gpiommc_configfs_device *dev = ci_to_gpiommc(item);
-+
-+ kfree(dev);
-+}
-+
-+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_configfs_device *dev;
-+
-+ if (strlen(name) > GPIOMMC_MAX_NAMELEN) {
-+ printk(KERN_ERR PFX "configfs: device name too long\n");
-+ return NULL;
-+ }
-+
-+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
-+ if (!dev)
-+ return NULL;
-+
-+ config_item_init_type_name(&dev->item, name,
-+ &gpiommc_dev_ci_type);
-+
-+ /* 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 &(dev->item);
-+}
-+
-+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,
-+ .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;
-+
-+#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 */
-+
-+ return 0;
-+}
-+module_init(gpiommc_modinit);
-+
-+static void __exit gpiommc_modexit(void)
-+{
-+#ifdef CONFIG_GPIOMMC_CONFIGFS
-+ configfs_unregister_subsystem(&gpiommc_subsys);
-+#endif
-+ platform_driver_unregister(&gpiommc_plat_driver);
-+}
-+module_exit(gpiommc_modexit);
---- a/drivers/mmc/host/Kconfig
-+++ b/drivers/mmc/host/Kconfig
-@@ -373,6 +373,31 @@ config MMC_TMIO
- This provides support for the SD/MMC cell found in TC6393XB,
- T7L66XB and also HTC ASIC3
-
-+config GPIOMMC
-+ tristate "MMC/SD over GPIO-based SPI"
-+ depends on MMC && MMC_SPI && SPI_GPIO_OLD
-+ 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 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.
-+
-+ The module will be called gpiommc.
-+
-+ If unsure, say N.
-+
-+config GPIOMMC_CONFIGFS
-+ bool
-+ depends on GPIOMMC && CONFIGFS_FS
-+ default y
-+ help
-+ This option automatically enables configfs support for gpiommc
-+ if configfs is available.
-+
- config MMC_CB710
- tristate "ENE CB710 MMC/SD Interface support"
- depends on PCI
---- a/drivers/mmc/host/Makefile
-+++ b/drivers/mmc/host/Makefile
-@@ -34,6 +34,7 @@ obj-$(CONFIG_MMC_SDRICOH_CS) += sdricoh_
- obj-$(CONFIG_MMC_TMIO) += tmio_mmc.o
- obj-$(CONFIG_MMC_CB710) += cb710-mmc.o
- obj-$(CONFIG_MMC_VIA_SDMMC) += via-sdmmc.o
-+obj-$(CONFIG_GPIOMMC) += gpiommc.o
- obj-$(CONFIG_SDH_BFIN) += bfin_sdh.o
-
- obj-$(CONFIG_MMC_SDHCI_OF) += sdhci-of.o
---- /dev/null
-+++ b/include/linux/mmc/gpiommc.h
-@@ -0,0 +1,71 @@
-+/*
-+ * 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
-+#define GPIOMMC_MAX_NAMELEN_STR __stringify(GPIOMMC_MAX_NAMELEN)
-+
-+/**
-+ * 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_ */
---- /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.
-+
-+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
-+=======================================
-+
-+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. (So the
-+struct may be allocated on the stack, too).
-+Now simply register the platform device.
-+
-+ err = platform_device_add(pdev);
-+
-+Done. The gpiommc probe routine will be invoked now and you should see a kernel
-+log message for the added device.
-+
-+
-+Registering devices via configfs
-+================================
-+
-+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.
-+
-+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.
---- a/MAINTAINERS
-+++ b/MAINTAINERS
-@@ -2443,6 +2443,11 @@ T: git git://git.kernel.org/pub/scm/linu
- S: Maintained
- F: drivers/media/video/gspca/
-
-+GPIOMMC DRIVER
-+P: Michael Buesch
-+M: mb@bu3sch.de
-+S: Maintained
-+
- HARDWARE MONITORING
- L: lm-sensors@lm-sensors.org
- W: http://www.lm-sensors.org/
projects / openwrt / openwrt.git / blobdiff