target/linux/generic/patches-3.2/862-gpio_spi_driver.patch

   1 THIS CODE IS DEPRECATED.
   2
   3 Please use the new mainline SPI-GPIO driver, as of 2.6.29.
   4
   5 --mb
   6
   7
   8
   9 ---
  10  drivers/spi/Kconfig              |    9 +
  11  drivers/spi/Makefile             |    1
  12  drivers/spi/spi_gpio_old.c       |  251 +++++++++++++++++++++++++++++++++++++++
  13  include/linux/spi/spi_gpio_old.h |   73 +++++++++++
  14  4 files changed, 334 insertions(+)
  15
  16 --- /dev/null
  17 +++ b/include/linux/spi/spi_gpio_old.h
  18 @@ -0,0 +1,73 @@
  19 +/*
  20 + * spi_gpio interface to platform code
  21 + *
  22 + * Copyright (c) 2008 Piotr Skamruk
  23 + * Copyright (c) 2008 Michael Buesch
  24 + *
  25 + * This program is free software; you can redistribute it and/or modify
  26 + * it under the terms of the GNU General Public License version 2 as
  27 + * published by the Free Software Foundation.
  28 + */
  29 +#ifndef _LINUX_SPI_SPI_GPIO
  30 +#define _LINUX_SPI_SPI_GPIO
  31 +
  32 +#include <linux/types.h>
  33 +#include <linux/spi/spi.h>
  34 +
  35 +
  36 +/**
  37 + * struct spi_gpio_platform_data - Data definitions for a SPI-GPIO device.
  38 + *
  39 + * This structure holds information about a GPIO-based SPI device.
  40 + *
  41 + * @pin_clk: The GPIO pin number of the CLOCK pin.
  42 + *
  43 + * @pin_miso: The GPIO pin number of the MISO pin.
  44 + *
  45 + * @pin_mosi: The GPIO pin number of the MOSI pin.
  46 + *
  47 + * @pin_cs: The GPIO pin number of the CHIPSELECT pin.
  48 + *
  49 + * @cs_activelow: If true, the chip is selected when the CS line is low.
  50 + *
  51 + * @no_spi_delay: If true, no delay is done in the lowlevel bitbanging.
  52 + *                Note that doing no delay is not standards compliant,
  53 + *                but it might be needed to speed up transfers on some
  54 + *                slow embedded machines.
  55 + *
  56 + * @boardinfo_setup: This callback is called after the
  57 + *                   SPI master device was registered, but before the
  58 + *                   device is registered.
  59 + * @boardinfo_setup_data: Data argument passed to boardinfo_setup().
  60 + */
  61 +struct spi_gpio_platform_data {
  62 +       unsigned int pin_clk;
  63 +       unsigned int pin_miso;
  64 +       unsigned int pin_mosi;
  65 +       unsigned int pin_cs;
  66 +       bool cs_activelow;
  67 +       bool no_spi_delay;
  68 +       int (*boardinfo_setup)(struct spi_board_info *bi,
  69 +                              struct spi_master *master,
  70 +                              void *data);
  71 +       void *boardinfo_setup_data;
  72 +};
  73 +
  74 +/**
  75 + * SPI_GPIO_PLATDEV_NAME - The platform device name string.
  76 + *
  77 + * The name string that has to be used for platform_device_alloc
  78 + * when allocating a spi-gpio device.
  79 + */
  80 +#define SPI_GPIO_PLATDEV_NAME  "spi-gpio"
  81 +
  82 +/**
  83 + * spi_gpio_next_id - Get another platform device ID number.
  84 + *
  85 + * This returns the next platform device ID number that has to be used
  86 + * for platform_device_alloc. The ID is opaque and should not be used for
  87 + * anything else.
  88 + */
  89 +int spi_gpio_next_id(void);
  90 +
  91 +#endif /* _LINUX_SPI_SPI_GPIO */
  92 --- /dev/null
  93 +++ b/drivers/spi/spi_gpio_old.c
  94 @@ -0,0 +1,251 @@
  95 +/*
  96 + * Bitbanging SPI bus driver using GPIO API
  97 + *
  98 + * Copyright (c) 2008 Piotr Skamruk
  99 + * Copyright (c) 2008 Michael Buesch
 100 + *
 101 + * based on spi_s3c2410_gpio.c
 102 + *   Copyright (c) 2006 Ben Dooks
 103 + *   Copyright (c) 2006 Simtec Electronics
 104 + * and on i2c-gpio.c
 105 + *   Copyright (C) 2007 Atmel Corporation
 106 + *
 107 + * This program is free software; you can redistribute it and/or modify
 108 + * it under the terms of the GNU General Public License version 2 as
 109 + * published by the Free Software Foundation.
 110 + */
 111 +
 112 +#include <linux/kernel.h>
 113 +#include <linux/init.h>
 114 +#include <linux/delay.h>
 115 +#include <linux/spinlock.h>
 116 +#include <linux/workqueue.h>
 117 +#include <linux/module.h>
 118 +#include <linux/platform_device.h>
 119 +#include <linux/spi/spi.h>
 120 +#include <linux/spi/spi_bitbang.h>
 121 +#include <linux/spi/spi_gpio_old.h>
 122 +#include <linux/gpio.h>
 123 +#include <asm/atomic.h>
 124 +
 125 +
 126 +struct spi_gpio {
 127 +       struct spi_bitbang bitbang;
 128 +       struct spi_gpio_platform_data *info;
 129 +       struct platform_device *pdev;
 130 +       struct spi_board_info bi;
 131 +};
 132 +
 133 +
 134 +static inline struct spi_gpio *spidev_to_sg(struct spi_device *dev)
 135 +{
 136 +       return dev->controller_data;
 137 +}
 138 +
 139 +static inline void setsck(struct spi_device *dev, int val)
 140 +{
 141 +       struct spi_gpio *sp = spidev_to_sg(dev);
 142 +       gpio_set_value(sp->info->pin_clk, val ? 1 : 0);
 143 +}
 144 +
 145 +static inline void setmosi(struct spi_device *dev, int val)
 146 +{
 147 +       struct spi_gpio *sp = spidev_to_sg(dev);
 148 +       gpio_set_value(sp->info->pin_mosi, val ? 1 : 0);
 149 +}
 150 +
 151 +static inline u32 getmiso(struct spi_device *dev)
 152 +{
 153 +       struct spi_gpio *sp = spidev_to_sg(dev);
 154 +       return gpio_get_value(sp->info->pin_miso) ? 1 : 0;
 155 +}
 156 +
 157 +static inline void do_spidelay(struct spi_device *dev, unsigned nsecs)
 158 +{
 159 +       struct spi_gpio *sp = spidev_to_sg(dev);
 160 +
 161 +       if (!sp->info->no_spi_delay)
 162 +               ndelay(nsecs);
 163 +}
 164 +
 165 +#define spidelay(nsecs) do {                                   \
 166 +       /* Steal the spi_device pointer from our caller.        \
 167 +        * The bitbang-API should probably get fixed here... */ \
 168 +       do_spidelay(spi, nsecs);                                \
 169 +  } while (0)
 170 +
 171 +#define EXPAND_BITBANG_TXRX
 172 +#include "spi-bitbang-txrx.h"
 173 +
 174 +static u32 spi_gpio_txrx_mode0(struct spi_device *spi,
 175 +                              unsigned nsecs, u32 word, u8 bits)
 176 +{
 177 +       return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
 178 +}
 179 +
 180 +static u32 spi_gpio_txrx_mode1(struct spi_device *spi,
 181 +                              unsigned nsecs, u32 word, u8 bits)
 182 +{
 183 +       return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits);
 184 +}
 185 +
 186 +static u32 spi_gpio_txrx_mode2(struct spi_device *spi,
 187 +                              unsigned nsecs, u32 word, u8 bits)
 188 +{
 189 +       return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits);
 190 +}
 191 +
 192 +static u32 spi_gpio_txrx_mode3(struct spi_device *spi,
 193 +                              unsigned nsecs, u32 word, u8 bits)
 194 +{
 195 +       return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits);
 196 +}
 197 +
 198 +static void spi_gpio_chipselect(struct spi_device *dev, int on)
 199 +{
 200 +       struct spi_gpio *sp = spidev_to_sg(dev);
 201 +
 202 +       if (sp->info->cs_activelow)
 203 +               on = !on;
 204 +       gpio_set_value(sp->info->pin_cs, on ? 1 : 0);
 205 +}
 206 +
 207 +static int spi_gpio_probe(struct platform_device *pdev)
 208 +{
 209 +       struct spi_master *master;
 210 +       struct spi_gpio_platform_data *pdata;
 211 +       struct spi_gpio *sp;
 212 +       struct spi_device *spidev;
 213 +       int err;
 214 +
 215 +       pdata = pdev->dev.platform_data;
 216 +       if (!pdata)
 217 +               return -ENXIO;
 218 +
 219 +       err = -ENOMEM;
 220 +       master = spi_alloc_master(&pdev->dev, sizeof(struct spi_gpio));
 221 +       if (!master)
 222 +               goto err_alloc_master;
 223 +
 224 +       sp = spi_master_get_devdata(master);
 225 +       platform_set_drvdata(pdev, sp);
 226 +       sp->info = pdata;
 227 +
 228 +       err = gpio_request(pdata->pin_clk, "spi_clock");
 229 +       if (err)
 230 +               goto err_request_clk;
 231 +       err = gpio_request(pdata->pin_mosi, "spi_mosi");
 232 +       if (err)
 233 +               goto err_request_mosi;
 234 +       err = gpio_request(pdata->pin_miso, "spi_miso");
 235 +       if (err)
 236 +               goto err_request_miso;
 237 +       err = gpio_request(pdata->pin_cs, "spi_cs");
 238 +       if (err)
 239 +               goto err_request_cs;
 240 +
 241 +       sp->bitbang.master = spi_master_get(master);
 242 +       sp->bitbang.master->bus_num = -1;
 243 +       sp->bitbang.master->num_chipselect = 1;
 244 +       sp->bitbang.chipselect = spi_gpio_chipselect;
 245 +       sp->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_txrx_mode0;
 246 +       sp->bitbang.txrx_word[SPI_MODE_1] = spi_gpio_txrx_mode1;
 247 +       sp->bitbang.txrx_word[SPI_MODE_2] = spi_gpio_txrx_mode2;
 248 +       sp->bitbang.txrx_word[SPI_MODE_3] = spi_gpio_txrx_mode3;
 249 +
 250 +       gpio_direction_output(pdata->pin_clk, 0);
 251 +       gpio_direction_output(pdata->pin_mosi, 0);
 252 +       gpio_direction_output(pdata->pin_cs,
 253 +                             pdata->cs_activelow ? 1 : 0);
 254 +       gpio_direction_input(pdata->pin_miso);
 255 +
 256 +       err = spi_bitbang_start(&sp->bitbang);
 257 +       if (err)
 258 +               goto err_no_bitbang;
 259 +       err = pdata->boardinfo_setup(&sp->bi, master,
 260 +                                    pdata->boardinfo_setup_data);
 261 +       if (err)
 262 +               goto err_bi_setup;
 263 +       sp->bi.controller_data = sp;
 264 +       spidev = spi_new_device(master, &sp->bi);
 265 +       if (!spidev)
 266 +               goto err_new_dev;
 267 +
 268 +       return 0;
 269 +
 270 +err_new_dev:
 271 +err_bi_setup:
 272 +       spi_bitbang_stop(&sp->bitbang);
 273 +err_no_bitbang:
 274 +       spi_master_put(sp->bitbang.master);
 275 +       gpio_free(pdata->pin_cs);
 276 +err_request_cs:
 277 +       gpio_free(pdata->pin_miso);
 278 +err_request_miso:
 279 +       gpio_free(pdata->pin_mosi);
 280 +err_request_mosi:
 281 +       gpio_free(pdata->pin_clk);
 282 +err_request_clk:
 283 +       kfree(master);
 284 +
 285 +err_alloc_master:
 286 +       return err;
 287 +}
 288 +
 289 +static int __devexit spi_gpio_remove(struct platform_device *pdev)
 290 +{
 291 +       struct spi_gpio *sp;
 292 +       struct spi_gpio_platform_data *pdata;
 293 +
 294 +       pdata = pdev->dev.platform_data;
 295 +       sp = platform_get_drvdata(pdev);
 296 +
 297 +       gpio_free(pdata->pin_clk);
 298 +       gpio_free(pdata->pin_mosi);
 299 +       gpio_free(pdata->pin_miso);
 300 +       gpio_free(pdata->pin_cs);
 301 +       spi_bitbang_stop(&sp->bitbang);
 302 +       spi_master_put(sp->bitbang.master);
 303 +
 304 +       return 0;
 305 +}
 306 +
 307 +static struct platform_driver spi_gpio_driver = {
 308 +       .driver         = {
 309 +               .name   = SPI_GPIO_PLATDEV_NAME,
 310 +               .owner  = THIS_MODULE,
 311 +       },
 312 +       .probe          = spi_gpio_probe,
 313 +       .remove         = __devexit_p(spi_gpio_remove),
 314 +};
 315 +
 316 +int spi_gpio_next_id(void)
 317 +{
 318 +       static atomic_t counter = ATOMIC_INIT(-1);
 319 +
 320 +       return atomic_inc_return(&counter);
 321 +}
 322 +EXPORT_SYMBOL(spi_gpio_next_id);
 323 +
 324 +static int __init spi_gpio_init(void)
 325 +{
 326 +       int err;
 327 +
 328 +       err = platform_driver_register(&spi_gpio_driver);
 329 +       if (err)
 330 +               printk(KERN_ERR "spi-gpio: register failed: %d\n", err);
 331 +
 332 +       return err;
 333 +}
 334 +module_init(spi_gpio_init);
 335 +
 336 +static void __exit spi_gpio_exit(void)
 337 +{
 338 +       platform_driver_unregister(&spi_gpio_driver);
 339 +}
 340 +module_exit(spi_gpio_exit);
 341 +
 342 +MODULE_AUTHOR("Piot Skamruk <piotr.skamruk at gmail.com>");
 343 +MODULE_AUTHOR("Michael Buesch");
 344 +MODULE_DESCRIPTION("Platform independent GPIO bitbanging SPI driver");
 345 +MODULE_LICENSE("GPL v2");
 346 --- a/drivers/spi/Kconfig
 347 +++ b/drivers/spi/Kconfig
 348 @@ -154,6 +154,15 @@ config SPI_GPIO
 349           GPIO operations, you should be able to leverage that for better
 350           speed with a custom version of this driver; see the source code.
 351
 352 +config SPI_GPIO_OLD
 353 +       tristate "Old GPIO API based bitbanging SPI controller (DEPRECATED)"
 354 +       depends on SPI_MASTER && GENERIC_GPIO
 355 +       select SPI_BITBANG
 356 +       help
 357 +         This code is deprecated. Please use the new mainline SPI-GPIO driver.
 358 +
 359 +         If unsure, say N.
 360 +
 361  config SPI_IMX
 362         tristate "Freescale i.MX SPI controllers"
 363         depends on ARCH_MXC
 364 --- a/drivers/spi/Makefile
 365 +++ b/drivers/spi/Makefile
 366 @@ -29,6 +29,7 @@ obj-$(CONFIG_SPI_FSL_LIB)             += spi-fsl-li
 367  obj-$(CONFIG_SPI_FSL_ESPI)             += spi-fsl-espi.o
 368  obj-$(CONFIG_SPI_FSL_SPI)              += spi-fsl-spi.o
 369  obj-$(CONFIG_SPI_GPIO)                 += spi-gpio.o
 370 +obj-$(CONFIG_SPI_GPIO_OLD)             += spi_gpio_old.o
 371  obj-$(CONFIG_SPI_IMX)                  += spi-imx.o
 372  obj-$(CONFIG_SPI_LM70_LLP)             += spi-lm70llp.o
 373  obj-$(CONFIG_SPI_MPC512x_PSC)          += spi-mpc512x-psc.o