Add an rpmsg driver sample, which demonstrates how to communicate with an AMP-configured remote processor over the rpmsg bus. The driver repeatedly sends a "Hello World!" message to the remote processor. Note that once probed, the driver can immediately start sending messages using the rpmsg_send() API, without having to worry about creating endpoints or allocating rpmsg addresses: all that work is done by the rpmsg bus, and the required information is already embedded in the rpmsg channel that the driver is probed with. Designed with Brian Swetland <swetland@xxxxxxxxxx>. Signed-off-by: Ohad Ben-Cohen <ohad@xxxxxxxxxx> Cc: Brian Swetland <swetland@xxxxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: Grant Likely <grant.likely@xxxxxxxxxxxx> Cc: Tony Lindgren <tony@xxxxxxxxxxx> Cc: Russell King <linux@xxxxxxxxxxxxxxxx> Cc: Rusty Russell <rusty@xxxxxxxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Greg KH <greg@xxxxxxxxx> Cc: Stephen Boyd <sboyd@xxxxxxxxxxxxxx> --- samples/Kconfig | 8 +++ samples/Makefile | 2 +- samples/amp/Makefile | 1 + samples/amp/rpmsg_client_sample.c | 100 +++++++++++++++++++++++++++++++++++++ 4 files changed, 110 insertions(+), 1 deletions(-) create mode 100644 samples/amp/Makefile create mode 100644 samples/amp/rpmsg_client_sample.c diff --git a/samples/Kconfig b/samples/Kconfig index 96a7572..997ddd3 100644 --- a/samples/Kconfig +++ b/samples/Kconfig @@ -67,4 +67,12 @@ config SAMPLE_HIDRAW help Build an example of how to use hidraw from userspace. +config SAMPLE_RPMSG_CLIENT + tristate "Build rpmsg client sample -- loadable modules only" + depends on RPMSG && m + help + Build an rpmsg client sample driver, which demonstrates how + to communicate with an AMP-configured remote processor over + the rpmsg bus. + endif # SAMPLES diff --git a/samples/Makefile b/samples/Makefile index 6280817..040f424 100644 --- a/samples/Makefile +++ b/samples/Makefile @@ -1,4 +1,4 @@ # Makefile for Linux samples code obj-$(CONFIG_SAMPLES) += kobject/ kprobes/ tracepoints/ trace_events/ \ - hw_breakpoint/ kfifo/ kdb/ hidraw/ + hw_breakpoint/ kfifo/ kdb/ hidraw/ amp/ diff --git a/samples/amp/Makefile b/samples/amp/Makefile new file mode 100644 index 0000000..2d4973c --- /dev/null +++ b/samples/amp/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_SAMPLE_RPMSG_CLIENT) += rpmsg_client_sample.o diff --git a/samples/amp/rpmsg_client_sample.c b/samples/amp/rpmsg_client_sample.c new file mode 100644 index 0000000..7b23380 --- /dev/null +++ b/samples/amp/rpmsg_client_sample.c @@ -0,0 +1,100 @@ +/* + * Remote processor messaging - sample client driver + * + * Copyright (C) 2011 Texas Instruments, Inc. + * Copyright (C) 2011 Google, Inc. + * + * Ohad Ben-Cohen <ohad@xxxxxxxxxx> + * Brian Swetland <swetland@xxxxxxxxxx> + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * 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/kernel.h> +#include <linux/module.h> +#include <linux/amp/rpmsg.h> + +#define MSG "hello world!" +#define MSG_LIMIT 100 + +static void rpmsg_sample_cb(struct rpmsg_channel *rpdev, void *data, int len, + void *priv, u32 src) +{ + int ret; + static int rx_count; + + dev_info(&rpdev->dev, "incoming msg %d (src: 0x%x)\n", ++rx_count, src); + + print_hex_dump(KERN_DEBUG, __func__, DUMP_PREFIX_NONE, 16, 1, + data, len, true); + + /* samples should not live forever */ + if (rx_count >= MSG_LIMIT) { + dev_info(&rpdev->dev, "goodbye!\n"); + return; + } + + /* send a new message now */ + ret = rpmsg_send(rpdev, MSG, strlen(MSG)); + if (ret) + dev_err(&rpdev->dev, "rpmsg_send failed: %d\n", ret); +} + +static int rpmsg_sample_probe(struct rpmsg_channel *rpdev) +{ + int ret; + + dev_info(&rpdev->dev, "new channel: 0x%x -> 0x%x!\n", + rpdev->src, rpdev->dst); + + /* send a message to our remote processor */ + ret = rpmsg_send(rpdev, MSG, strlen(MSG)); + if (ret) { + dev_err(&rpdev->dev, "rpmsg_send failed: %d\n", ret); + return ret; + } + + return 0; +} + +static void __devexit rpmsg_sample_remove(struct rpmsg_channel *rpdev) +{ + dev_info(&rpdev->dev, "rpmsg sample client driver is removed\n"); +} + +static struct rpmsg_device_id rpmsg_driver_sample_id_table[] = { + { .name = "rpmsg-client-sample" }, + { }, +}; +MODULE_DEVICE_TABLE(rpmsg, rpmsg_driver_sample_id_table); + +static struct rpmsg_driver rpmsg_sample_client = { + .drv.name = KBUILD_MODNAME, + .drv.owner = THIS_MODULE, + .id_table = rpmsg_driver_sample_id_table, + .probe = rpmsg_sample_probe, + .callback = rpmsg_sample_cb, + .remove = __devexit_p(rpmsg_sample_remove), +}; + +static int __init rpmsg_client_sample_init(void) +{ + return register_rpmsg_driver(&rpmsg_sample_client); +} +module_init(rpmsg_client_sample_init); + +static void __exit rpmsg_client_sample_fini(void) +{ + unregister_rpmsg_driver(&rpmsg_sample_client); +} +module_exit(rpmsg_client_sample_fini); + +MODULE_DESCRIPTION("Remote processor messaging sample client driver"); +MODULE_LICENSE("GPL v2"); -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html