stm class: dummy_stm: Add dummy driver for testing stm class

	  Examples of such devices are Intel(R) Trace Hub and Coresight STM.

	  Say Y here to enable System Trace Module device support.

config STM_DUMMY

	tristate "Dummy STM driver"

	help

	  This is a simple dummy device that pretends to be an stm device

	  and discards your data. Use for stm class testing.

	  If you don't know what this is, say N.

obj-$(CONFIG_STM)	+= stm_core.o

stm_core-y		:= core.o policy.o

obj-$(CONFIG_STM_DUMMY)	+= dummy_stm.o

/*

 * A dummy STM device for stm/stm_source class testing.

 * Copyright (c) 2014, Intel Corporation.

 *

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

 * under the terms and conditions of the GNU General Public License,

 * version 2, as published by the Free Software Foundation.

 *

 * This program is distributed in the hope 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.

 *

 * STM class implements generic infrastructure for  System Trace Module devices

 * as defined in MIPI STPv2 specification.

 */

#undef DEBUG

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/slab.h>

#include <linux/stm.h>

static ssize_t

dummy_stm_packet(struct stm_data *stm_data, unsigned int master,

		 unsigned int channel, unsigned int packet, unsigned int flags,

		 unsigned int size, const unsigned char *payload)

{

#ifdef DEBUG

	u64 pl = 0;

	if (payload)

		pl = *(u64 *)payload;

	if (size < 8)

		pl &= (1ull << (size * 8)) - 1;

	trace_printk("[%u:%u] [pkt: %x/%x] (%llx)\n", master, channel,

		     packet, size, pl);

#endif

	return size;

}

static struct stm_data dummy_stm = {

	.name		= "dummy_stm",

	.sw_start	= 0x0000,

	.sw_end		= 0xffff,

	.sw_nchannels	= 0xffff,

	.packet		= dummy_stm_packet,

};

static int dummy_stm_init(void)

{

	return stm_register_device(NULL, &dummy_stm, THIS_MODULE);

}

static void dummy_stm_exit(void)

{

	stm_unregister_device(&dummy_stm);

}

module_init(dummy_stm_init);

module_exit(dummy_stm_exit);

MODULE_LICENSE("GPL v2");

MODULE_DESCRIPTION("dummy_stm device");

MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");