greybus: add support for the log protocol (c0e65d02) · Commits · 戴 / test

drivers/staging/greybus/Makefile

+2 −0

Original line number	Diff line number	Diff line
		@@ -18,6 +18,7 @@ gb-gbphy-y := gbphy.o
		# Prefix all modules with gb-
		gb-vibrator-y := vibrator.o
		gb-power-supply-y := power_supply.o
		gb-log-y := log.o
		gb-loopback-y := loopback.o
		gb-light-y := light.o
		gb-raw-y := raw.o
		@@ -46,6 +47,7 @@ obj-m += greybus.o
		obj-m += gb-gbphy.o
		obj-m += gb-vibrator.o
		obj-m += gb-power-supply.o
		obj-m += gb-log.o
		obj-m += gb-loopback.o
		obj-m += gb-light.o
		obj-m += gb-hid.o

drivers/staging/greybus/greybus_manifest.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -47,6 +47,7 @@ enum greybus_protocol {
		GREYBUS_PROTOCOL_CAMERA_DATA = 0x16,
		GREYBUS_PROTOCOL_FW_DOWNLOAD = 0x17,
		GREYBUS_PROTOCOL_FW_MANAGEMENT = 0x18,
		GREYBUS_PROTOCOL_LOG = 0x1a,
		/* ... */
		GREYBUS_PROTOCOL_RAW = 0xfe,
		GREYBUS_PROTOCOL_VENDOR = 0xff,
		@@ -76,6 +77,7 @@ enum greybus_class_type {
		/* 0x14 is unused */
		GREYBUS_CLASS_BOOTROM = 0x15,
		GREYBUS_CLASS_FW_MANAGEMENT = 0x16,
		GREYBUS_CLASS_LOG = 0x17,
		/* ... */
		GREYBUS_CLASS_RAW = 0xfe,
		GREYBUS_CLASS_VENDOR = 0xff,

drivers/staging/greybus/greybus_protocols.h

+14 −0

Original line number	Diff line number	Diff line
		@@ -2136,5 +2136,19 @@ struct gb_audio_send_data_request {
		__u8 data[0];
		} __packed;


		/* Log */

		/* operations */
		#define GB_LOG_TYPE_SEND_LOG 0x02

		/* length */
		#define GB_LOG_MAX_LEN 1024

		struct gb_log_send_log_request {
		__le16 len;
		__u8 msg[0];
		} __packed;

		#endif /* __GREYBUS_PROTOCOLS_H */

drivers/staging/greybus/log.c

0 → 100644

+132 −0

Original line number	Diff line number	Diff line
		/*
		* Greybus driver for the log protocol
		*
		* Copyright 2016 Google Inc.
		*
		* Released under the GPLv2 only.
		*/
		#include <linux/kernel.h>
		#include <linux/module.h>
		#include <linux/slab.h>
		#include <linux/sizes.h>
		#include <linux/uaccess.h>

		#include "greybus.h"

		struct gb_log {
		struct gb_connection *connection;
		};

		static int gb_log_request_handler(struct gb_operation *op)
		{
		struct gb_connection *connection = op->connection;
		struct device *dev = &connection->bundle->dev;
		struct gb_log_send_log_request *receive;
		u16 len;

		if (op->type != GB_LOG_TYPE_SEND_LOG) {
		dev_err(dev, "unknown request type 0x%02x\n", op->type);
		return -EINVAL;
		}

		/* Verify size of payload */
		if (op->request->payload_size < sizeof(*receive)) {
		dev_err(dev, "log request too small (%zu < %zu)\n",
		op->request->payload_size, sizeof(*receive));
		return -EINVAL;
		}
		receive = op->request->payload;
		len = le16_to_cpu(receive->len);
		if (len != (int)(op->request->payload_size - sizeof(*receive))) {
		dev_err(dev, "log request wrong size %d vs %d\n", len,
		(int)(op->request->payload_size - sizeof(*receive)));
		return -EINVAL;
		}
		if (len == 0) {
		dev_err(dev, "log request of 0 bytes?\n");
		return -EINVAL;
		}

		if (len > GB_LOG_MAX_LEN) {
		dev_err(dev, "log request too big: %d\n", len);
		return -EINVAL;
		}

		/* Ensure the buffer is 0 terminated */
		receive->msg[len - 1] = '\0';

		/* Print with dev_dbg() so that it can be easily turned off using
		* dynamic debugging (and prevent any DoS) */
		dev_dbg(dev, "%s", receive->msg);

		return 0;
		}

		static int gb_log_probe(struct gb_bundle *bundle,
		const struct greybus_bundle_id *id)
		{
		struct greybus_descriptor_cport *cport_desc;
		struct gb_connection *connection;
		struct gb_log *log;
		int retval;

		if (bundle->num_cports != 1)
		return -ENODEV;

		cport_desc = &bundle->cport_desc[0];
		if (cport_desc->protocol_id != GREYBUS_PROTOCOL_LOG)
		return -ENODEV;

		log = kzalloc(sizeof(*log), GFP_KERNEL);
		if (!log)
		return -ENOMEM;

		connection = gb_connection_create(bundle, le16_to_cpu(cport_desc->id),
		gb_log_request_handler);
		if (IS_ERR(connection)) {
		retval = PTR_ERR(connection);
		goto error_free;
		}

		log->connection = connection;
		greybus_set_drvdata(bundle, log);

		retval = gb_connection_enable(connection);
		if (retval)
		goto error_connection_destroy;

		return 0;

		error_connection_destroy:
		gb_connection_destroy(connection);
		error_free:
		kfree(log);
		return retval;
		}

		static void gb_log_disconnect(struct gb_bundle *bundle)
		{
		struct gb_log *log = greybus_get_drvdata(bundle);
		struct gb_connection *connection = log->connection;

		gb_connection_disable(connection);
		gb_connection_destroy(connection);

		kfree(log);
		}

		static const struct greybus_bundle_id gb_log_id_table[] = {
		{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_LOG) },
		{ }
		};
		MODULE_DEVICE_TABLE(greybus, gb_log_id_table);

		static struct greybus_driver gb_log_driver = {
		.name = "log",
		.probe = gb_log_probe,
		.disconnect = gb_log_disconnect,
		.id_table = gb_log_id_table,
		};
		module_greybus_driver(gb_log_driver);

		MODULE_LICENSE("GPL v2");

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