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path: root/target/linux/generic/patches-3.3/862-gpio_spi_driver.patch
blob: 6cbea32a3186fd7e5b542e17da0438743d811809 (plain)
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8' href='#n238'>238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373
THIS CODE IS DEPRECATED.

Please use the new mainline SPI-GPIO driver, as of 2.6.29.

--mb



---
 drivers/spi/Kconfig              |    9 +
 drivers/spi/Makefile             |    1 
 drivers/spi/spi_gpio_old.c       |  251 +++++++++++++++++++++++++++++++++++++++
 include/linux/spi/spi_gpio_old.h |   73 +++++++++++
 4 files changed, 334 insertions(+)

--- /dev/null
+++ b/include/linux/spi/spi_gpio_old.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_old.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_old.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 "spi-bitbang-txrx.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, 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, 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, 0, 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, 0, 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
@@ -154,6 +154,15 @@ config SPI_GPIO
 	  GPIO operations, you should be able to leverage that for better
 	  speed with a custom version of this driver; see the source code.
 
+config SPI_GPIO_OLD
+	tristate "Old GPIO API based bitbanging SPI controller (DEPRECATED)"
+	depends on SPI_MASTER && GENERIC_GPIO
+	select SPI_BITBANG
+	help
+	  This code is deprecated. Please use the new mainline SPI-GPIO driver.
+
+	  If unsure, say N.
+
 config SPI_IMX
 	tristate "Freescale i.MX SPI controllers"
 	depends on ARCH_MXC
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_SPI_FSL_LIB)		+= spi-fsl-li
 obj-$(CONFIG_SPI_FSL_ESPI)		+= spi-fsl-espi.o
 obj-$(CONFIG_SPI_FSL_SPI)		+= spi-fsl-spi.o
 obj-$(CONFIG_SPI_GPIO)			+= spi-gpio.o
+obj-$(CONFIG_SPI_GPIO_OLD)		+= spi_gpio_old.o
 obj-$(CONFIG_SPI_IMX)			+= spi-imx.o
 obj-$(CONFIG_SPI_LM70_LLP)		+= spi-lm70llp.o
 obj-$(CONFIG_SPI_MPC512x_PSC)		+= spi-mpc512x-psc.o