Gilad Arnold | 1ebd813 | 2012-03-05 10:19:29 -0800 | [diff] [blame] | 1 | // Copyright (c) 2012 The Chromium OS Authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #ifndef CHROMEOS_PLATFORM_UPDATE_ENGINE_GPIO_HANDLER_H__ |
| 6 | #define CHROMEOS_PLATFORM_UPDATE_ENGINE_GPIO_HANDLER_H__ |
| 7 | |
| 8 | #include <libudev.h> |
| 9 | |
| 10 | #include <string> |
| 11 | |
| 12 | #include <base/basictypes.h> |
| 13 | |
| 14 | namespace chromeos_update_engine { |
| 15 | |
| 16 | // Handles GPIO signals, which are used for indicating a lab test environment. |
| 17 | // This class detects, reads and decides whether a test scenario is in effect, |
| 18 | // which can be used by client code to trigger test-specific behavior. This |
| 19 | // class has only static members/methods and cannot be instantiated. |
| 20 | class GpioHandler { |
| 21 | public: |
| 22 | // Returns true iff GPIOs have been signaled to indicate an automated test |
| 23 | // case. This triggers a discovery and reading of the dutflaga/b GPIOs. |
| 24 | static bool IsGpioSignalingTest(); |
| 25 | |
| 26 | private: |
| 27 | // This class cannot be instantiated. |
| 28 | GpioHandler() {} |
| 29 | |
| 30 | // Enumerator for dutflag GPIOs. |
| 31 | enum DutflagGpioId { |
| 32 | kDutflagaGpio, |
| 33 | kDutflagbGpio, |
| 34 | }; |
| 35 | |
| 36 | // Gets the fully qualified sysfs name of a dutflag device. |udev| is a live |
| 37 | // libudev instance; |gpio_dutflag_str| is the identifier for the requested |
| 38 | // dutflag GPIO. The output is stored in the string pointed to by |
| 39 | // |dutflag_dev_name_p|. Returns true upon success, false otherwise. |
| 40 | static bool GetDutflagGpioDevName(struct udev* udev, |
| 41 | const std::string& gpio_dutflag_str, |
| 42 | const char** dutflag_dev_name_p); |
| 43 | |
| 44 | // Gets the dut_flaga/b GPIO device names and copies them into the two string |
| 45 | // arguments, respectively. A string pointer may be null, in which case |
| 46 | // discovery will not be attempted for the corresponding device. The function |
| 47 | // caches these strings, which are assumed to be hardware constants. Returns |
| 48 | // true upon success, false otherwise. |
| 49 | static bool GetDutflagGpioDevNames(std::string* dutflaga_dev_name_p, |
| 50 | std::string* dutflagb_dev_name_p); |
| 51 | |
| 52 | // Writes the dut_flaga GPIO status into its argument, where true/false stand |
| 53 | // for "on"/"off", respectively. Returns true upon success, false otherwise |
| 54 | // (in which case no value is written to |status|). |
| 55 | static bool GetDutflagaGpio(bool* status); |
| 56 | |
| 57 | // Reads the value of a dut_flag GPIO |id| and stores it in |status_p|. |
| 58 | // Returns true upon success, false otherwise (which also means that the GPIO |
| 59 | // value was not stored and should not be used). |
| 60 | static bool GetDutflagGpioStatus(DutflagGpioId id, bool* status_p); |
| 61 | |
| 62 | // Dutflaga/b GPIO device names. |
| 63 | static const char* dutflaga_dev_name_; |
| 64 | static const char* dutflagb_dev_name_; |
| 65 | |
| 66 | DISALLOW_COPY_AND_ASSIGN(GpioHandler); |
| 67 | }; |
| 68 | |
| 69 | } // namespace chromeos_update_engine |
| 70 | |
| 71 | #endif // CHROMEOS_PLATFORM_UPDATE_ENGINE_GPIO_HANDLER_H__ |