From 2c41538191e1ee34e316aaba586fb2cab1379a3a Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Tue, 22 Sep 2015 15:47:12 +0300 Subject: [PATCH] stm class: dummy_stm: Add dummy driver for testing stm class This is a simple module that pretends to be an stm device and discards all the data that comes in. Useful for testing stm class and its users. Reviewed-by: Mathieu Poirier Signed-off-by: Alexander Shishkin Signed-off-by: Greg Kroah-Hartman --- drivers/hwtracing/stm/Kconfig | 8 ++++ drivers/hwtracing/stm/Makefile | 2 + drivers/hwtracing/stm/dummy_stm.c | 66 +++++++++++++++++++++++++++++++ 3 files changed, 76 insertions(+) create mode 100644 drivers/hwtracing/stm/dummy_stm.c diff --git a/drivers/hwtracing/stm/Kconfig b/drivers/hwtracing/stm/Kconfig index e101cb4f8e43..49c098400c54 100644 --- a/drivers/hwtracing/stm/Kconfig +++ b/drivers/hwtracing/stm/Kconfig @@ -6,3 +6,11 @@ config STM 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. diff --git a/drivers/hwtracing/stm/Makefile b/drivers/hwtracing/stm/Makefile index adec7016499f..1b2725fd04d1 100644 --- a/drivers/hwtracing/stm/Makefile +++ b/drivers/hwtracing/stm/Makefile @@ -1,3 +1,5 @@ obj-$(CONFIG_STM) += stm_core.o stm_core-y := core.o policy.o + +obj-$(CONFIG_STM_DUMMY) += dummy_stm.o diff --git a/drivers/hwtracing/stm/dummy_stm.c b/drivers/hwtracing/stm/dummy_stm.c new file mode 100644 index 000000000000..3709bef0b21f --- /dev/null +++ b/drivers/hwtracing/stm/dummy_stm.c @@ -0,0 +1,66 @@ +/* + * 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 +#include +#include +#include + +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 "); -- 2.20.1