From e3e5a3d3da3e68ac5a7ab0278dffec8353ca8174 Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Tue, 22 Sep 2015 15:47:13 +0300 Subject: [PATCH] stm class: stm_console: Add kernel-console-over-stm driver This is a simple stm_source class device driver (kernelspace stm trace source) that registers a console and sends kernel messages over STM devices. Reviewed-by: Mathieu Poirier Signed-off-by: Alexander Shishkin Signed-off-by: Greg Kroah-Hartman --- drivers/hwtracing/stm/Kconfig | 9 ++++ drivers/hwtracing/stm/Makefile | 4 ++ drivers/hwtracing/stm/console.c | 80 +++++++++++++++++++++++++++++++++ 3 files changed, 93 insertions(+) create mode 100644 drivers/hwtracing/stm/console.c diff --git a/drivers/hwtracing/stm/Kconfig b/drivers/hwtracing/stm/Kconfig index 49c098400c54..5a59a28cc3da 100644 --- a/drivers/hwtracing/stm/Kconfig +++ b/drivers/hwtracing/stm/Kconfig @@ -14,3 +14,12 @@ config STM_DUMMY and discards your data. Use for stm class testing. If you don't know what this is, say N. + +config STM_SOURCE_CONSOLE + tristate "Kernel console over STM devices" + help + This is a kernel space trace source that sends kernel log + messages to trace hosts over STM devices. + + If you want to send kernel console messages over STM devices, + say Y. diff --git a/drivers/hwtracing/stm/Makefile b/drivers/hwtracing/stm/Makefile index 1b2725fd04d1..f9312c38dd7a 100644 --- a/drivers/hwtracing/stm/Makefile +++ b/drivers/hwtracing/stm/Makefile @@ -3,3 +3,7 @@ obj-$(CONFIG_STM) += stm_core.o stm_core-y := core.o policy.o obj-$(CONFIG_STM_DUMMY) += dummy_stm.o + +obj-$(CONFIG_STM_SOURCE_CONSOLE) += stm_console.o + +stm_console-y := console.o diff --git a/drivers/hwtracing/stm/console.c b/drivers/hwtracing/stm/console.c new file mode 100644 index 000000000000..c9d9a8d2ff52 --- /dev/null +++ b/drivers/hwtracing/stm/console.c @@ -0,0 +1,80 @@ +/* + * Simple kernel console driver for STM devices + * 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 console will send kernel messages over STM devices to a trace host. + */ + +#include +#include +#include +#include +#include + +static int stm_console_link(struct stm_source_data *data); +static void stm_console_unlink(struct stm_source_data *data); + +static struct stm_console { + struct stm_source_data data; + struct console console; +} stm_console = { + .data = { + .name = "console", + .nr_chans = 1, + .link = stm_console_link, + .unlink = stm_console_unlink, + }, +}; + +static void +stm_console_write(struct console *con, const char *buf, unsigned len) +{ + struct stm_console *sc = container_of(con, struct stm_console, console); + + stm_source_write(&sc->data, 0, buf, len); +} + +static int stm_console_link(struct stm_source_data *data) +{ + struct stm_console *sc = container_of(data, struct stm_console, data); + + strcpy(sc->console.name, "stm_console"); + sc->console.write = stm_console_write; + sc->console.flags = CON_ENABLED | CON_PRINTBUFFER; + register_console(&sc->console); + + return 0; +} + +static void stm_console_unlink(struct stm_source_data *data) +{ + struct stm_console *sc = container_of(data, struct stm_console, data); + + unregister_console(&sc->console); +} + +static int stm_console_init(void) +{ + return stm_source_register_device(NULL, &stm_console.data); +} + +static void stm_console_exit(void) +{ + stm_source_unregister_device(&stm_console.data); +} + +module_init(stm_console_init); +module_exit(stm_console_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("stm_console driver"); +MODULE_AUTHOR("Alexander Shishkin "); -- 2.20.1