linux-imx

/*

 *  linux/drivers/spi/spi-loopback-test.c

 *

 *  (c) Martin Sperl <kernel@martin.sperl.org>

 *

 *  Loopback test driver to test several typical spi_message conditions

 *  that a spi_master driver may encounter

 *  this can also get used for regression testing

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; either version 2 of the License, or

 *  (at your option) any later version.

 *

 *  This program is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *  GNU General Public License for more details.

 */

​

#include <linux/delay.h>

#include <linux/kernel.h>

#include <linux/ktime.h>

#include <linux/list.h>

#include <linux/list_sort.h>

#include <linux/module.h>

#include <linux/of_device.h>

#include <linux/printk.h>

#include <linux/vmalloc.h>

#include <linux/spi/spi.h>

​

#include "spi-test.h"

​

/* flag to only simulate transfers */

static int simulate_only;

module_param(simulate_only, int, 0);

MODULE_PARM_DESC(simulate_only, "if not 0 do not execute the spi message");

​

/* dump spi messages */

static int dump_messages;

module_param(dump_messages, int, 0);

MODULE_PARM_DESC(dump_messages,

         "=1 dump the basic spi_message_structure, " \

         "=2 dump the spi_message_structure including data, " \

         "=3 dump the spi_message structure before and after execution");

/* the device is jumpered for loopback - enabling some rx_buf tests */

static int loopback;

module_param(loopback, int, 0);

MODULE_PARM_DESC(loopback,

         "if set enable loopback mode, where the rx_buf "   \

         "is checked to match tx_buf after the spi_message "    \

         "is executed");

​

static int loop_req;

module_param(loop_req, int, 0);

MODULE_PARM_DESC(loop_req,

         "if set controller will be asked to enable test loop mode. " \

         "If controller supported it, MISO and MOSI will be connected");

​

static int no_cs;

module_param(no_cs, int, 0);

MODULE_PARM_DESC(no_cs,

         "if set Chip Select (CS) will not be used");