在FramebufferNativeWindow.cpp : FramebufferNativeWindow::FramebufferNativeWindow() : BASE(), fbDev(0), grDev(0), mUpdateOnDemand(false) { hw_module_t const* module; if (hw_get_module(GRALLOC_HARDWARE_MODULE_ID, &module) == 0) { int stride; int err; int i; err = framebuffer_open(module, &fbDev); LOGE_IF(err, "couldn't open framebuffer HAL (%s)", strerror(-err)); err = gralloc_open(module, &grDev); LOGE_IF(err, "couldn't open gralloc HAL (%s)", strerror(-err)); // bail out if we can't initialize the modules if (!fbDev || !grDev)

hw_get_module 是所有 hareware module 的 loading interface

hardware/libhardware/hardware.c

hw_get_module 其實就是依照 property set 的 module path, name ，要 dlopen 去 load 這個 so 近來。
在用 dlsym 取出 so 的 HAL_MODULE_INFO_SYM_AS_STR 這個 function 的 位址.

在這裡就是 .. GRALLOC_HARDWAE_MODULE_ID. ./hardware/libhardware/include/hardware/gralloc.h:36:#define GRALLOC_HARDWARE_MODULE_ID "gralloc" hw_get_module 會到3 個位置去找： /* Loop through the configuration variants looking for a module */ for (i=0 ; i< HAL_VARIANT_KEYS_COUNT+1 ; i++) { if (i < HAL_VARIANT_KEYS_COUNT) { if (property_get(variant_keys[i], prop, NULL) == 0) { continue; } snprintf(path, sizeof(path), "%s/%s.%s.so", HAL_LIBRARY_PATH1, id, prop); if (access(path, R_OK) == 0) break; snprintf(path, sizeof(path), "%s/%s.%s.so", HAL_LIBRARY_PATH2, id, prop); if (access(path, R_OK) == 0) break; } else { snprintf(path, sizeof(path), "%s/%s.default.so", HAL_LIBRARY_PATH1, id); if (access(path, R_OK) == 0) break; } } 其中 ..
./hardware/libhardware/hardware.c:31:#define HAL_LIBRARY_PATH1 "/system/lib/hw" ./hardware/libhardware/hardware.c:32:#define HAL_LIBRARY_PATH2 "/vendor/lib/hw"
的確在 ..

/system/lib/hw/

有

gralloc.imx5x.so

---

取出的 function 叫 HMI..
gralloc 的 hmi interface 定義是： static struct hw_module_methods_t gralloc_module_methods = { open: gralloc_device_open }; struct private_module_t HAL_MODULE_INFO_SYM = { base: { common: { tag: HARDWARE_MODULE_TAG, version_major: 1, version_minor: 0, id: GRALLOC_HARDWARE_MODULE_ID, name: "Graphics Memory Allocator Module", author: "The Android Open Source Project", methods: &gralloc_module_methods }, registerBuffer: gralloc_register_buffer, unregisterBuffer: gralloc_unregister_buffer, lock: gralloc_lock, unlock: gralloc_unlock, }, framebuffer: 0, flags: 0, numBuffers: 0, bufferMask: 0, lock: PTHREAD_MUTEX_INITIALIZER, currentBuffer: 0, pmem_master: -1, pmem_master_base: 0, master_phys: 0 };