Add functions to read MTP events from MTP devices. (8a7ffae0) · Commits · e / os / android_frameworks_av

media/mtp/MtpDevice.cpp

+39 −1

Original line number	Diff line number	Diff line
		@@ -204,7 +204,9 @@ MtpDevice::MtpDevice(struct usb_device* device, int interface,
		mDeviceInfo(NULL),
		mSessionID(0),
		mTransactionID(0),
		mReceivedResponse(false)
		mReceivedResponse(false),
		mProcessingEvent(false),
		mCurrentEventHandle(0)
		{
		mRequestIn1 = usb_request_new(device, ep_in);
		mRequestIn2 = usb_request_new(device, ep_in);
		@@ -794,4 +796,40 @@ MtpResponseCode MtpDevice::readResponse() {
		}
		}

		int MtpDevice::submitEventRequest() {
		if (mEventMutex.tryLock()) {
		// An event is being reaped on another thread.
		return -1;
		}
		if (mProcessingEvent) {
		// An event request was submitted, but no reapEventRequest called so far.
		return -1;
		}
		Mutex::Autolock autoLock(mEventMutexForInterrupt);
		mEventPacket.sendRequest(mRequestIntr);
		const int currentHandle = ++mCurrentEventHandle;
		mProcessingEvent = true;
		mEventMutex.unlock();
		return currentHandle;
		}

		int MtpDevice::reapEventRequest(int handle) {
		Mutex::Autolock autoLock(mEventMutex);
		if (!mProcessingEvent \|\| mCurrentEventHandle != handle) {
		return -1;
		}
		mProcessingEvent = false;
		const int readSize = mEventPacket.readResponse(mRequestIntr->dev);
		const int result = mEventPacket.getEventCode();
		return readSize == 0 ? 0 : result;
		}

		void MtpDevice::discardEventRequest(int handle) {
		Mutex::Autolock autoLock(mEventMutexForInterrupt);
		if (mCurrentEventHandle != handle) {
		return;
		}
		usb_request_cancel(mRequestIntr);
		}

		} // namespace android

media/mtp/MtpDevice.h

+21 −2

Original line number	Diff line number	Diff line
		@@ -17,8 +17,9 @@
		#ifndef _MTP_DEVICE_H
		#define _MTP_DEVICE_H

		#include "MtpRequestPacket.h"
		#include "MtpEventPacket.h"
		#include "MtpDataPacket.h"
		#include "MtpRequestPacket.h"
		#include "MtpResponsePacket.h"
		#include "MtpTypes.h"

		@@ -31,6 +32,7 @@ struct usb_endpoint_descriptor;
		namespace android {

		class MtpDeviceInfo;
		class MtpEventPacket;
		class MtpObjectInfo;
		class MtpStorageInfo;

		@@ -53,11 +55,17 @@ private:
		MtpRequestPacket mRequest;
		MtpDataPacket mData;
		MtpResponsePacket mResponse;
		MtpEventPacket mEventPacket;

		// set to true if we received a response packet instead of a data packet
		bool mReceivedResponse;
		bool mProcessingEvent;
		int mCurrentEventHandle;

		// to ensure only one MTP transaction at a time
		Mutex mMutex;
		Mutex mEventMutex;
		Mutex mEventMutexForInterrupt;

		public:
		typedef bool (ReadObjectCallback)(void data, int offset, int length, void* clientData);
		@@ -101,6 +109,18 @@ public:
		bool readObject(MtpObjectHandle handle, const char* destPath, int group,
		int perm);
		bool readObject(MtpObjectHandle handle, int fd);
		// Starts a request to read MTP event from MTP device. It returns a request handle that
		// can be used for blocking read or cancel. If other thread has already been processing an
		// event returns -1.
		int submitEventRequest();
		// Waits for MTP event from the device and returns MTP event code. It blocks the current thread
		// until it receives an event from the device. \|handle\| should be a request handle returned
		// by \|submitEventRequest\|. Returns 0 for cancellations. Returns -1 for errors.
		int reapEventRequest(int handle);
		// Cancels an event request. \|handle\| should be request handle returned by
		// \|submitEventRequest\|. If there is a thread blocked by \|reapEventRequest\| with the same
		// \|handle\|, the thread will resume.
		void discardEventRequest(int handle);

		private:
		// If \|objectSize\| is not NULL, it checks object size before reading data bytes.
		@@ -111,7 +131,6 @@ private:
		bool readData();
		bool writeDataHeader(MtpOperationCode operation, int dataLength);
		MtpResponseCode readResponse();

		};

		}; // namespace android

media/mtp/MtpEventPacket.cpp

+17 −8

Original line number	Diff line number	Diff line
		@@ -54,17 +54,26 @@ int MtpEventPacket::write(int fd) {
		#endif

		#ifdef MTP_HOST
		int MtpEventPacket::read(struct usb_request *request) {
		int MtpEventPacket::sendRequest(struct usb_request *request) {
		request->buffer = mBuffer;
		request->buffer_length = mBufferSize;
		int ret = transfer(request);
		if (ret >= 0)
		mPacketSize = ret;
		else
		mPacketSize = 0;
		return ret;
		if (usb_request_queue(request)) {
		ALOGE("usb_endpoint_queue failed, errno: %d", errno);
		return -1;
		}
		return 0;
		}

		int MtpEventPacket::readResponse(struct usb_device *device) {
		struct usb_request* const req = usb_request_wait(device);
		if (req) {
		mPacketSize = req->actual_length;
		return req->actual_length;
		} else {
		return -1;
		}
		}
		#endif

		} // namespace android

media/mtp/MtpEventPacket.h

+2 −1

Original line number	Diff line number	Diff line
		@@ -35,7 +35,8 @@ public:

		#ifdef MTP_HOST
		// read our buffer with the given request
		int read(struct usb_request *request);
		int sendRequest(struct usb_request *request);
		int readResponse(struct usb_device *device);
		#endif

		inline MtpEventCode getEventCode() const { return getContainerCode(); }

media/mtp/MtpPacket.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -19,6 +19,7 @@

		#include "MtpTypes.h"

		struct usb_device;
		struct usb_request;

		namespace android {