| /**************************************************************************** |
| * apps/graphics/ft80x/ft80x_backlight.c |
| * |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. The |
| * ASF licenses this file to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance with the |
| * License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| * License for the specific language governing permissions and limitations |
| * under the License. |
| * |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Included Files |
| ****************************************************************************/ |
| |
| #include <nuttx/config.h> |
| |
| #include <sys/ioctl.h> |
| #include <stdint.h> |
| #include <assert.h> |
| #include <errno.h> |
| |
| #include <nuttx/lcd/ft80x.h> |
| |
| #include "graphics/ft80x.h" |
| #include "ft80x.h" |
| |
| /**************************************************************************** |
| * Public Functions |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Name: ft80x_backlight_set |
| * |
| * Description: |
| * Set the backlight intensity via the PWM duty. |
| * |
| * Input Parameters: |
| * fd - The file descriptor of the FT80x device. Opened by the caller |
| * with write access. |
| * duty - The new backlight duty (as a percentage 0..100) |
| * |
| * Returned Value: |
| * Zero (OK) on success. A negated errno value on failure. |
| * |
| ****************************************************************************/ |
| |
| int ft80x_backlight_set(int fd, uint8_t duty) |
| { |
| uint16_t duty128; |
| int ret; |
| |
| DEBUGASSERT(duty <= 100); |
| |
| /* 0% corresponds to the value 0, but 100% corresponds to the value 128 */ |
| |
| duty128 = ((uint16_t)duty << 7) / 100; |
| |
| /* Perform the IOCTL to set the backlight duty */ |
| |
| ret = ft80x_putreg8(fd, FT80X_REG_PWM_DUTY, (uint8_t)duty128); |
| if (ret < 0) |
| { |
| ft80x_err("ERROR: ft80x_putreg8 failed: %d\n", ret); |
| } |
| |
| return ret; |
| } |
| |
| /**************************************************************************** |
| * Name: ft80x_backlight_fade |
| * |
| * Description: |
| * Change the backlight intensity with a controllable fade. |
| * |
| * Input Parameters: |
| * fd - The file descriptor of the FT80x device. Opened by the caller |
| * with write access. |
| * duty - The terminal duty (as a percentage 0..100) |
| * delay - The duration of the fade in milliseconds (10..16700) |
| * |
| * Returned Value: |
| * Zero (OK) on success. A negated errno value on failure. |
| * |
| ****************************************************************************/ |
| |
| int ft80x_backlight_fade(int fd, uint8_t duty, uint16_t delay) |
| { |
| struct ft80x_fade_s fade; |
| int ret; |
| |
| DEBUGASSERT(duty <= 100); |
| |
| /* Perform the IOCTL to perform the fade */ |
| |
| fade.duty = duty; |
| fade.delay = delay; |
| |
| ret = ioctl(fd, FT80X_IOC_FADE, (unsigned long)((uintptr_t)&fade)); |
| if (ret < 0) |
| { |
| int errcode = errno; |
| ft80x_err("ERROR: ioctl(FT80X_IOC_FADE) failed: %d\n", errcode); |
| ret = -errcode; |
| } |
| |
| return ret; |
| } |