nuttx/drivers/lcd/apa102.c
2022-08-15 00:32:42 +08:00

748 lines
21 KiB
C

/****************************************************************************
* drivers/lcd/apa102.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.
*
****************************************************************************/
/* Driver to create a display using RBG LEDs APA102 chained together */
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/arch.h>
#include <nuttx/spi/spi.h>
#include <nuttx/lcd/lcd.h>
#include <nuttx/lcd/apa102.h>
#include <nuttx/leds/apa102.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifndef MAX
# define MAX(a,b) ((a) > (b) ? (a) : (b))
#endif
/* Configuration ************************************************************/
/* APA102 Configuration Settings:
*
* CONFIG_APA102_XRES - Specifies the number of physical
* APA102 devices that are connected together horizontally.
*
* CONFIG_APA102_YRES - Specifies the number of physical
* APA102 devices that are connected together vertically.
*
* CONFIG_LCD_INTENSITY - Defines the default bright of LEDs.
*
* Required LCD driver settings:
* CONFIG_LCD_APA102 - Enable APA102 support
*
*/
/* Verify that all configuration requirements have been met */
/* SPI frequency */
#ifndef CONFIG_APA102_FREQUENCY
# define CONFIG_APA102_FREQUENCY 10000000
#endif
/* APA102_COLUMNS determines the number of physical LEDs
* matrices that are used connected horizontally.
*/
#ifndef CONFIG_APA102_XRES
# define CONFIG_APA102_XRES 16
#endif
/* APA102_LINES determines the number of physical LEDs
* matrices that are used connected vertically.
*/
#ifndef CONFIG_APA102_YRES
# define CONFIG_APA102_YRES 16
#endif
/* Check contrast selection */
#if !defined(CONFIG_LCD_MAXCONTRAST)
# define CONFIG_LCD_MAXCONTRAST 1
#endif
/* Color Properties *********************************************************/
/* Display Resolution */
#define APA102_XRES CONFIG_APA102_XRES
#define APA102_YRES CONFIG_APA102_YRES
/* Color depth and format */
#define APA102_BPP 16
#define APA102_COLORFMT FB_FMT_RGB16_565
#define APA102_LUT_SIZE MAX(APA102_XRES, APA102_YRES)
/* The size of the shadow frame buffer (4 bytes per LED) */
#define APA102_FBSIZE (APA102_XRES * APA102_YRES)
/* LCD RGB Mapping */
#ifdef CONFIG_FB_CMAP
# error "RGB color mapping not supported by this driver"
#endif
/* Cursor Controls */
#ifdef CONFIG_FB_HWCURSOR
# error "Cursor control not supported by this driver"
#endif
/****************************************************************************
* Private Type Definition
****************************************************************************/
/* This structure describes the state of this driver */
struct apa102_dev_s
{
/* Publicly visible device structure */
struct lcd_dev_s dev;
/* Private LCD-specific information follows */
FAR struct spi_dev_s *spi;
uint8_t contrast;
uint8_t powered;
/* We need to send all the APA102 matrix screen once.
* So, create a framebuffer to save it in memory
*/
struct apa102_ledstrip_s fb[APA102_FBSIZE];
};
/****************************************************************************
* Private Function Protototypes
****************************************************************************/
/* LCD Data Transfer Methods */
static int apa102_putrun(FAR struct lcd_dev_s *dev, fb_coord_t row,
fb_coord_t col, FAR const uint8_t *buffer,
size_t npixels);
static int apa102_putarea(FAR struct lcd_dev_s *dev,
fb_coord_t row_start, fb_coord_t row_end,
fb_coord_t col_start, fb_coord_t col_end,
FAR const uint8_t *buffer, fb_coord_t stride);
static int apa102_getrun(FAR struct lcd_dev_s *dev, fb_coord_t row,
fb_coord_t col, FAR uint8_t *buffer,
size_t npixels);
/* LCD Configuration */
static int apa102_getvideoinfo(FAR struct lcd_dev_s *dev,
FAR struct fb_videoinfo_s *vinfo);
static int apa102_getplaneinfo(FAR struct lcd_dev_s *dev,
unsigned int planeno,
FAR struct lcd_planeinfo_s *pinfo);
/* LCD Specific Controls */
static int apa102_getpower(FAR struct lcd_dev_s *dev);
static int apa102_setpower(FAR struct lcd_dev_s *dev, int power);
static int apa102_getcontrast(FAR struct lcd_dev_s *dev);
static int apa102_setcontrast(FAR struct lcd_dev_s *dev,
unsigned int contrast);
/* Initialization */
static inline void up_clear(FAR struct apa102_dev_s *priv);
/****************************************************************************
* Private Data
****************************************************************************/
/* This is working memory allocated by the LCD driver for each LCD device
* and for each color plane. This memory will hold one raster line of data.
* The size of the allocated run buffer must therefore be at least
* (bpp * xres / 8). Actual alignment of the buffer must conform to the
* bitwidth of the underlying pixel type.
*
* If there are multiple planes, they may share the same working buffer
* because different planes will not be operate on concurrently. However,
* if there are multiple LCD devices, they must each have unique run buffers.
*/
static uint8_t g_runbuffer[APA102_LUT_SIZE];
/* This structure describes the overall LCD video controller */
static const struct fb_videoinfo_s g_videoinfo =
{
APA102_COLORFMT, /* Color format: RGB16-565: RRRR RGGG GGGB BBBB */
APA102_XRES, /* Horizontal resolution in pixel columns */
APA102_YRES, /* Vertical resolution in pixel rows */
1, /* Number of color planes supported */
};
/* This is the standard, NuttX Plane information object */
static const struct lcd_planeinfo_s g_planeinfo =
{
apa102_putrun, /* Put a run into LCD memory */
apa102_putarea, /* Put a run into LCD memory */
apa102_getrun, /* Get a run from LCD memory */
NULL, /* No getarea function */
NULL, /* No redraw function */
(FAR uint8_t *)g_runbuffer, /* Run scratch buffer */
APA102_BPP, /* Bits-per-pixel */
NULL, /* Put lcd_dev_s later */
};
/* This is the standard, NuttX LCD driver object */
static struct apa102_dev_s g_apa102dev =
{
/* struct lcd_dev_s */
{
/* LCD Configuration */
apa102_getvideoinfo,
apa102_getplaneinfo,
#ifdef CONFIG_FB_CMAP
/* LCD RGB Mapping -- Not supported */
NULL,
NULL,
#endif
#ifdef CONFIG_FB_HWCURSOR
/* Cursor Controls -- Not supported */
NULL,
NULL,
#endif
/* LCD Specific Controls */
apa102_getpower,
apa102_setpower,
apa102_getcontrast,
apa102_setcontrast,
},
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: rgb565_apa102
*
* Description:
* Convert RGB565 to APA102 RGB888 format
*
****************************************************************************/
static struct apa102_ledstrip_s rgb565_apa102(uint16_t rgb565)
{
struct apa102_ledstrip_s led;
led.red = (rgb565 & 0b1111100000000000) >> 8;
led.green = (rgb565 & 0b11111100000) >> 3;
led.blue = (rgb565 & 0b11111) << 3;
led.bright = 0;
return led;
}
/****************************************************************************
* Name: apa102_rgb565
*
* Description:
* Convert APA102 RGB888 to RGB565 format
*
****************************************************************************/
static uint16_t apa102_rgb565(struct apa102_ledstrip_s led)
{
uint16_t pixel;
pixel = (led.red & 0b11111000) << 8;
pixel |= (led.green & 0b11111100) << 3;
pixel |= (led.blue & 0b11111000) >> 3;
return pixel;
}
/****************************************************************************
* Name: apa102_configspi
*
* Description:
* Set the SPI bus configuration
*
****************************************************************************/
static inline void apa102_configspi(FAR struct spi_dev_s *spi)
{
/* Configure SPI for the APA102 */
SPI_SETMODE(spi, SPIDEV_MODE0);
SPI_SETBITS(spi, 8);
SPI_HWFEATURES(spi, 0);
SPI_SETFREQUENCY(spi, APA102_SPI_MAXFREQUENCY);
}
/****************************************************************************
* Name: apa102_write32
*
* Description:
* Write 32-bit to APA102
*
****************************************************************************/
static inline void apa102_write32(FAR struct apa102_dev_s *priv,
uint32_t value)
{
/* If SPI bus is shared then lock and configure it */
SPI_LOCK(priv->spi, true);
/* Note: APA102 doesn't use chip select */
/* Send 32 bits (4 bytes) */
SPI_SEND(priv->spi, (value & 0xff));
SPI_SEND(priv->spi, ((value & 0xff00) >> 8));
SPI_SEND(priv->spi, ((value & 0xff0000) >> 16));
SPI_SEND(priv->spi, ((value & 0xff000000) >> 24));
/* Unlock bus */
SPI_LOCK(priv->spi, false);
}
/****************************************************************************
* Name: apa102_refresh
*
* Description:
* Send converted framebuffer to the APA102 LED Matrix
*
****************************************************************************/
static inline void apa102_refresh(FAR struct apa102_dev_s *priv)
{
int i;
/* Confirm that SPI is configured correctly */
apa102_configspi(priv->spi);
/* Send a start of frame */
apa102_write32(priv, APA102_START_FRAME);
/* Send all LEDs values in the matrix */
for (i = 0; i < (APA102_XRES * APA102_YRES); i++)
{
uint32_t *led = (uint32_t *) &priv->fb[i];
/* Then transfer 4 bytes per LED */
apa102_write32(priv, (uint32_t) (*led | APA102_HEADER_FRAME));
}
/* Send an end of frame */
apa102_write32(priv, APA102_END_FRAME);
for (i = 0; i < (1 + APA102_XRES * APA102_YRES / 32); i++)
{
apa102_write32(priv, 0);
}
}
/****************************************************************************
* Name: apa102_putrun
*
* Description:
* This method can be used to write a partial raster line to the LCD:
*
* dev - The lcd device
* row - Starting row to write to (range: 0 <= row < yres)
* col - Starting column to write to (range: 0 <= col <= xres-npixels)
* buffer - The buffer containing the run to be written to the LCD
* npixels - The number of pixels to write to the LCD
* (range: 0 < npixels <= xres-col)
*
****************************************************************************/
static int apa102_putrun(FAR struct lcd_dev_s *dev, fb_coord_t row,
fb_coord_t col, FAR const uint8_t *buffer,
size_t npixels)
{
/* Because of this line of code, we will only be able to support a single
* APA102 device .
*/
FAR struct apa102_dev_s *priv = (FAR struct apa102_dev_s *)dev;
int i;
int pixlen;
ginfo("row: %d col: %d npixels: %d\n", row, col, npixels);
DEBUGASSERT(buffer && ((uintptr_t)buffer & 1) == 0);
/* Clip the run to the display */
pixlen = npixels;
if ((unsigned int)col + (unsigned int)pixlen > (unsigned int)APA102_XRES)
{
pixlen = (int)APA102_XRES - (int)col;
}
/* Verify that some portion of the run remains on the display */
if (pixlen <= 0 || row > APA102_YRES)
{
return OK;
}
/* Convert rgb565 to APA102 LED values */
for (i = 0; i < pixlen; i++)
{
uint16_t *ptr = (uint16_t *)buffer;
if (row % 2 == 0)
{
priv->fb[(row * APA102_XRES) + col + i] = rgb565_apa102(*ptr++);
}
else
{
priv->fb[(row * APA102_XRES) + APA102_XRES - col - i - 1] =
rgb565_apa102(*ptr++);
}
}
/* Update the display with converted data */
apa102_refresh(priv);
return OK;
}
/****************************************************************************
* Name: apa102_putarea
*
* Description:
* This method can be used to write a partial area to the LCD:
*
* dev - The lcd device
* row_start - Starting row to write to (range: 0 <= row < yres)
* row_end - Ending row to write to (range: row_start <= row < yres)
* col_start - Starting column to write to (range: 0 <= col <= xres)
* col_end - Ending column to write to
* (range: col_start <= col_end < xres)
* buffer - The buffer containing the area to be written to the LCD
* stride - Length of a line in bytes. This parameter may be necessary
* to allow the LCD driver to calculate the offset for partial
* writes when the buffer needs to be splited for row-by-row
* writing.
*
****************************************************************************/
static int apa102_putarea(FAR struct lcd_dev_s *dev,
fb_coord_t row_start, fb_coord_t row_end,
fb_coord_t col_start, fb_coord_t col_end,
FAR const uint8_t *buffer, fb_coord_t stride)
{
FAR struct apa102_dev_s *priv = (FAR struct apa102_dev_s *)dev;
FAR uint16_t *src = (FAR uint16_t *)buffer;
int i;
int j;
ginfo("row_start: %d row_end: %d col_start: %d col_end: %d\n",
row_start, row_end, col_start, col_end);
DEBUGASSERT(buffer && ((uintptr_t)buffer & 1) == 0);
/* Convert RGB565 to APA102 LED values */
for (i = row_start; i <= row_end; i++)
{
for (j = col_start; j <= col_end; j++)
{
if (i % 2 == 0)
{
priv->fb[(i * APA102_XRES) + j] =
rgb565_apa102(*(src + ((i - row_start) * APA102_XRES) +
(j - col_start)));
}
else
{
priv->fb[(i * APA102_XRES) + APA102_XRES - j - 1] =
rgb565_apa102(*(src + ((i - row_start) * APA102_XRES) +
(j - col_start)));
}
}
}
/* Update the display with converted data */
apa102_refresh(priv);
return OK;
}
/****************************************************************************
* Name: apa102_getrun
*
* Description:
* This method can be used to read a partial raster line from the LCD:
*
* dev - The lcd device
* row - Starting row to read from (range: 0 <= row < yres)
* col - Starting column to read read (range: 0 <= col <= xres-npixels)
* buffer - The buffer in which to return the run read from the LCD
* npixels - The number of pixels to read from the LCD
* (range: 0 < npixels <= xres-col)
*
****************************************************************************/
static int apa102_getrun(FAR struct lcd_dev_s *dev, fb_coord_t row,
fb_coord_t col, FAR uint8_t *buffer,
size_t npixels)
{
/* Because of this line of code, we will only be able to support a single
* APA102 device.
*/
FAR struct apa102_dev_s *priv = (FAR struct apa102_dev_s *)dev;
int i;
int pixlen;
ginfo("row: %d col: %d npixels: %d\n", row, col, npixels);
DEBUGASSERT(buffer);
/* Clip the run to the display */
pixlen = npixels;
if ((unsigned int)col + (unsigned int)pixlen > (unsigned int)APA102_XRES)
{
pixlen = (int)APA102_XRES - (int)col;
}
/* Verify that some portion of the run is actually the display */
if (pixlen <= 0 || row > APA102_YRES)
{
return -EINVAL;
}
for (i = 0; i < pixlen; i++)
{
uint16_t *ptr = (uint16_t *) buffer;
*ptr++ = apa102_rgb565(priv->fb[(row * APA102_XRES) + col + i]);
}
return OK;
}
/****************************************************************************
* Name: apa102_getvideoinfo
*
* Description:
* Get information about the LCD video controller configuration.
*
****************************************************************************/
static int apa102_getvideoinfo(FAR struct lcd_dev_s *dev,
FAR struct fb_videoinfo_s *vinfo)
{
DEBUGASSERT(dev && vinfo);
ginfo("fmt: %d xres: %d yres: %d nplanes: %d\n",
g_videoinfo.fmt, g_videoinfo.xres, g_videoinfo.yres,
g_videoinfo.nplanes);
memcpy(vinfo, &g_videoinfo, sizeof(struct fb_videoinfo_s));
return OK;
}
/****************************************************************************
* Name: apa102_getplaneinfo
*
* Description:
* Get information about the configuration of each LCD color plane.
*
****************************************************************************/
static int apa102_getplaneinfo(FAR struct lcd_dev_s *dev,
unsigned int planeno,
FAR struct lcd_planeinfo_s *pinfo)
{
DEBUGASSERT(dev && pinfo && planeno == 0);
ginfo("planeno: %d bpp: %d\n", planeno, g_planeinfo.bpp);
memcpy(pinfo, &g_planeinfo, sizeof(struct lcd_planeinfo_s));
pinfo->dev = dev;
return OK;
}
/****************************************************************************
* Name: apa102_getpower
*
* Description:
* Get the LCD panel power status (0: full off - CONFIG_LCD_MAXPOWER: full
* on). On backlit LCDs, this setting may correspond to the backlight
* setting.
*
****************************************************************************/
static int apa102_getpower(FAR struct lcd_dev_s *dev)
{
struct apa102_dev_s *priv = (FAR struct apa102_dev_s *)dev;
DEBUGASSERT(priv);
ginfo("powered: %d\n", priv->powered);
return priv->powered;
}
/****************************************************************************
* Name: apa102_setpower
*
* Description:
* Enable/disable LCD panel power (0: full off - CONFIG_LCD_MAXPOWER: full
* on). On backlit LCDs, this setting may correspond to the backlight
* setting.
*
****************************************************************************/
static int apa102_setpower(FAR struct lcd_dev_s *dev, int power)
{
return OK;
}
/****************************************************************************
* Name: apa102_getcontrast
*
* Description:
* Get the current contrast setting (0-CONFIG_LCD_MAXCONTRAST).
*
****************************************************************************/
static int apa102_getcontrast(FAR struct lcd_dev_s *dev)
{
struct apa102_dev_s *priv = (FAR struct apa102_dev_s *)dev;
DEBUGASSERT(priv);
return (int)priv->contrast;
}
/****************************************************************************
* Name: apa102_setcontrast
*
* Description:
* Set LCD panel contrast (0-CONFIG_LCD_MAXCONTRAST).
*
****************************************************************************/
static int apa102_setcontrast(FAR struct lcd_dev_s *dev,
unsigned int contrast)
{
return OK;
}
/****************************************************************************
* Name: up_clear
*
* Description:
* Clear the display.
*
****************************************************************************/
static inline void up_clear(FAR struct apa102_dev_s *priv)
{
/* Clear the framebuffer */
memset(priv->fb, APA102_BLACK, 4 * APA102_FBSIZE);
/* Update the display with framebuffer data */
apa102_refresh(priv);
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: apa102_initialize
*
* Description:
* Initialize the APA102 device as a LCD interface.
*
* Input Parameters:
* spi - An instance of the SPI interface to use to communicate
* with the APA102.
* devno - Device number to identify current display.
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure.
*
****************************************************************************/
FAR struct lcd_dev_s *apa102_initialize(FAR struct spi_dev_s *spi,
unsigned int devno)
{
/* Configure and enable LCD */
FAR struct apa102_dev_s *priv = &g_apa102dev;
ginfo("Initializing\n");
DEBUGASSERT(spi && devno == 0);
/* Save the reference to the SPI device */
priv->spi = spi;
/* Clear the framebuffer */
up_clear(priv);
return &priv->dev;
}