diff options
Diffstat (limited to 'target/linux/generic-2.6/patches-2.6.30/922-gpiommc.patch')
-rw-r--r-- | target/linux/generic-2.6/patches-2.6.30/922-gpiommc.patch | 838 |
1 files changed, 0 insertions, 838 deletions
diff --git a/target/linux/generic-2.6/patches-2.6.30/922-gpiommc.patch b/target/linux/generic-2.6/patches-2.6.30/922-gpiommc.patch deleted file mode 100644 index c0a2159d86..0000000000 --- a/target/linux/generic-2.6/patches-2.6.30/922-gpiommc.patch +++ /dev/null @@ -1,838 +0,0 @@ ---- /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 -@@ -241,3 +241,28 @@ config MMC_TMIO - help - This provides support for the SD/MMC cell found in TC6393XB, - T7L66XB and also ipaq 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. ---- a/drivers/mmc/host/Makefile -+++ b/drivers/mmc/host/Makefile -@@ -29,4 +29,5 @@ endif - obj-$(CONFIG_MMC_S3C) += s3cmci.o - obj-$(CONFIG_MMC_SDRICOH_CS) += sdricoh_cs.o - obj-$(CONFIG_MMC_TMIO) += tmio_mmc.o -+obj-$(CONFIG_GPIOMMC) += gpiommc.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 -@@ -2504,6 +2504,11 @@ 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/ |