6c92951047
Move the common_time service developed in the ics-aah branch back into master. The common_time service is a small service build to synchronize an arbitrary timeline amongst peers on a local sub-net. While running and configured, the service will elect a master from the set of available devices within the subnet, define a relationship between the common_time timeline the local time timeline (provided by the local time HAL), and then attempt to maintain synchronization between common and local time by controlling the frequency of the local time clock via the HAL, or by disciplining local time in the digital domain if the local time HAL implementation does not support HW slewing. On its own, the native common time service will do nothing until it is configured. The CommonTimeManagementService (running out of the system server process) is responsible for implementing policy regarding configuration and operation of the common_time service and will be added in a subsequent CL. Change-Id: I71292f9b9b1797665865689c4572c9d3a0552f64 Signed-off-by: John Grossman <johngro@google.com>
58 lines
1.7 KiB
C++
58 lines
1.7 KiB
C++
/*
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* Copyright (C) 2012 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#ifndef __COMMON_CLOCK_H__
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#define __COMMON_CLOCK_H__
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#include <stdint.h>
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#include <utils/Errors.h>
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#include <utils/LinearTransform.h>
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#include <utils/threads.h>
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namespace android {
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class CommonClock {
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public:
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CommonClock();
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bool init(uint64_t local_freq);
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status_t localToCommon(int64_t local, int64_t *common_out) const;
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status_t commonToLocal(int64_t common, int64_t *local_out) const;
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int64_t localDurationToCommonDuration(int64_t localDur) const;
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uint64_t getCommonFreq() const { return kCommonFreq; }
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bool isValid() const { return cur_trans_valid_; }
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status_t setSlew(int64_t change_time, int32_t ppm);
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void setBasis(int64_t local, int64_t common);
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void resetBasis();
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private:
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mutable Mutex lock_;
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int32_t cur_slew_;
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uint32_t local_to_common_freq_numer_;
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uint32_t local_to_common_freq_denom_;
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LinearTransform duration_trans_;
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LinearTransform cur_trans_;
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bool cur_trans_valid_;
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static const uint64_t kCommonFreq = 1000000ull;
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};
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} // namespace android
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#endif // __COMMON_CLOCK_H__
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