diff options
5 files changed, 1249 insertions, 297 deletions
diff --git a/target/linux/generic-2.6/files-2.6.26/drivers/spi/spi_gpio.c b/target/linux/generic-2.6/files-2.6.26/drivers/spi/spi_gpio.c deleted file mode 100644 index 31048acc3..000000000 --- a/target/linux/generic-2.6/files-2.6.26/drivers/spi/spi_gpio.c +++ /dev/null @@ -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"); diff --git a/target/linux/generic-2.6/files-2.6.26/include/linux/spi/spi_gpio.h b/target/linux/generic-2.6/files-2.6.26/include/linux/spi/spi_gpio.h deleted file mode 100644 index 8e7d4b189..000000000 --- a/target/linux/generic-2.6/files-2.6.26/include/linux/spi/spi_gpio.h +++ /dev/null @@ -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 */ diff --git a/target/linux/generic-2.6/patches-2.6.26/921-gpio_spi_driver.patch b/target/linux/generic-2.6/patches-2.6.26/921-gpio_spi_driver.patch index eeb7285a0..2457cbe42 100644 --- a/target/linux/generic-2.6/patches-2.6.26/921-gpio_spi_driver.patch +++ b/target/linux/generic-2.6/patches-2.6.26/921-gpio_spi_driver.patch @@ -1,13 +1,351 @@ +--- /dev/null ++++ b/include/linux/spi/spi_gpio.h +@@ -0,0 +1,73 @@ ++/* ++ * 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 */ +--- /dev/null ++++ b/drivers/spi/spi_gpio.c +@@ -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"); --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig -@@ -100,6 +100,11 @@ +@@ -100,6 +100,19 @@ 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" @@ -22,3 +360,17 @@ obj-$(CONFIG_SPI_IMX) += spi_imx.o obj-$(CONFIG_SPI_LM70_LLP) += spi_lm70llp.o obj-$(CONFIG_SPI_PXA2XX) += pxa2xx_spi.o +--- a/MAINTAINERS ++++ b/MAINTAINERS +@@ -3795,6 +3795,11 @@ + W: http://www.ibm.com/developerworks/power/cell/ + S: Supported + ++SPI GPIO MASTER DRIVER ++P: Michael Buesch ++M: mb@bu3sch.de ++S: Maintained ++ + STABLE BRANCH: + P: Greg Kroah-Hartman + M: greg@kroah.com diff --git a/target/linux/generic-2.6/patches-2.6.26/922-gpiommc.patch b/target/linux/generic-2.6/patches-2.6.26/922-gpiommc.patch new file mode 100644 index 000000000..2fb3a34c6 --- /dev/null +++ b/target/linux/generic-2.6/patches-2.6.26/922-gpiommc.patch @@ -0,0 +1,837 @@ +--- /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.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 +@@ -130,3 +130,27 @@ + + 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 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 +@@ -17,4 +17,4 @@ + 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 +--- /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 +@@ -1818,6 +1818,11 @@ + 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 diff --git a/target/linux/generic-2.6/patches-2.6.26/923-gpiommc-configfs-locking.patch b/target/linux/generic-2.6/patches-2.6.26/923-gpiommc-configfs-locking.patch new file mode 100644 index 000000000..1d0f5ba65 --- /dev/null +++ b/target/linux/generic-2.6/patches-2.6.26/923-gpiommc-configfs-locking.patch @@ -0,0 +1,58 @@ +The gpiommc configfs context structure needs locking, as configfs +does not lock access between files. + +--- a/drivers/mmc/host/gpiommc.c ++++ b/drivers/mmc/host/gpiommc.c +@@ -143,6 +143,8 @@ + struct platform_device *pdev; + /* The configuration */ + struct gpiommc_platform_data pdata; ++ /* Mutex to protect this structure */ ++ struct mutex mutex; + }; + + #define GPIO_INVALID -1 +@@ -233,6 +235,8 @@ + unsigned int gpio; + int err = 0; + ++ mutex_lock(&dev->mutex); ++ + if (attr == &gpiommc_attr_DI) { + gpio = dev->pdata.pins.gpio_di; + if (gpio == GPIO_INVALID) +@@ -293,6 +297,8 @@ + WARN_ON(1); + err = -ENOSYS; + out: ++ mutex_unlock(&dev->mutex); ++ + return err ? err : count; + } + +@@ -352,6 +358,8 @@ + int err = -EINVAL; + unsigned long data; + ++ mutex_lock(&dev->mutex); ++ + if (attr == &gpiommc_attr_register) { + err = strict_strtoul(page, 10, &data); + if (err) +@@ -477,6 +485,8 @@ + WARN_ON(1); + err = -ENOSYS; + out: ++ mutex_unlock(&dev->mutex); ++ + return err ? err : count; + } + +@@ -513,6 +523,7 @@ + if (!dev) + return NULL; + ++ mutex_init(&dev->mutex); + config_item_init_type_name(&dev->item, name, + &gpiommc_dev_ci_type); + |