Google Git
Sign in
apache / nuttx / refs/heads/cmake / . / drivers / lcd / ht16k33_14seg.c
blob: 2d91284cf4f29dd52212dcd9452c6da19d38aa80 [file] [log] [blame]
/****************************************************************************
* drivers/lcd/ht16k33_14seg.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.
*
****************************************************************************/
/* Alphanumeric display driver for HOLTEK HT16K33 (and VINKA VK16K33 clone)
* This driver is specific for a 0.54" 14-segment LED HT16K33 Backpack
* module with 4 14-segment digits (2 Kingbright 5241AS display).
* Note: the model I'm testing uses the VK16K33.
*
* This is how the displays are connected:
* Left Display: Digit 1: Catode connected to COM3
* Left Display: Digit 2: Catode connected to COM2
* Right Display: Digit 1: Catode connected to COM1
* Right Display: Digit 2: Catode connected to COM0
*
* 14-Segment | LED Controller
* -------------------------------
* 8 - DP | ROW14 - 11
* 13 - p | ROW6 - 19
* 2 - n | ROW11 - 14
* 4 - m | ROW12 - 13
* 5 - l | ROW13 - 12
* 6 - k | ROW7 - 18
* 14 - j | ROW10 - 15
* 15 - h | ROW9 - 16
* 17 - g | ROW8 - 17
* 18 - f | ROW5 - 20
* 1 - e | ROW4 - 21
* 7 - d | ROW3 - 22
* 9 - c | ROW2 - 23
* 10 - b | ROW1 - 24
* 12 - a | ROW0 - 25
*/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdlib.h>
#include <errno.h>
#include <debug.h>
#include <string.h>
#include <nuttx/kmalloc.h>
#include <nuttx/mutex.h>
#include <nuttx/signal.h>
#include <nuttx/ascii.h>
#include <nuttx/fs/fs.h>
#include <nuttx/lcd/slcd_codec.h>
#include <nuttx/lcd/slcd_ioctl.h>
#include <nuttx/i2c/i2c_master.h>
#include <nuttx/lcd/ht16k33.h>
#ifndef CONFIG_LIBC_SLCDCODEC
# error please also select Library Routines, Segment LCD CODEC
#endif
#if defined(CONFIG_I2C) && defined(CONFIG_LCD_HT16K33)
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* I2C frequency */
#ifndef CONFIG_HT16K33_I2C_FREQ
# define CONFIG_HT16K33_I2C_FREQ 400000
#endif
#ifndef CONFIG_LCD_HT16K33_NUMBER_MODULES
# define CONFIG_LCD_HT16K33_NUMBER_MODULES 1
#endif
#define HT16K33_MAX_ROW 1
#define HT16K33_MAX_COL 4 * CONFIG_LCD_HT16K33_NUMBER_MODULES
/* Device naming ************************************************************/
#define DEVNAME_FMT "/dev/slcd%d"
#define DEVNAME_FMTLEN (9 + 3 + 1)
/****************************************************************************
* Private Types
****************************************************************************/
struct ht16k33_dev_s
{
FAR struct i2c_master_s *i2c; /* I2C interface */
uint8_t row; /* Current row position to write on display */
uint8_t col; /* Current col position to write on display */
uint8_t buffer[HT16K33_MAX_COL];
bool pendscroll;
mutex_t lock;
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static inline void ht16k33_write_cmd(FAR struct ht16k33_dev_s *priv,
int dev_id, uint8_t cmd);
static inline void ht16k33_write_data(FAR struct ht16k33_dev_s *priv,
int dev_id, uint8_t cmd,
uint8_t *values, int nbytes);
static inline void ht16k33_setcontrast(FAR struct ht16k33_dev_s *priv,
int dev_id, int8_t contrast);
static void lcd_scroll_up(FAR struct ht16k33_dev_s *priv);
static void ht16k33_clear_display(FAR struct ht16k33_dev_s *priv);
/* Character driver methods */
static ssize_t ht16k33_read(FAR struct file *filep, FAR char *buffer,
size_t buflen);
static ssize_t ht16k33_write(FAR struct file *filep, FAR const char *buffer,
size_t buflen);
static off_t ht16k33_seek(FAR struct file *filep, off_t offset,
int whence);
static int ht16k33_ioctl(FAR struct file *filep, int cmd,
unsigned long arg);
/****************************************************************************
* Private Data
****************************************************************************/
static const struct file_operations g_ht16k33fops =
{
NULL, /* open */
NULL, /* close */
ht16k33_read, /* read */
ht16k33_write, /* write */
ht16k33_seek, /* seek */
ht16k33_ioctl, /* ioctl */
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: ht16k33_write_cmd
*
* Description:
* Write an Instruction command to HT16K33
*
****************************************************************************/
static inline void ht16k33_write_cmd(FAR struct ht16k33_dev_s *priv,
int dev_id, uint8_t cmd)
{
struct i2c_msg_s msg;
uint8_t data[1];
int ret;
/* Prepare data to send */
data[0] = cmd;
/* Setup the HT16K33 Command */
msg.frequency = CONFIG_HT16K33_I2C_FREQ; /* I2C frequency */
msg.addr = HT16K33_I2C_ADDR + dev_id; /* 7-bit address */
msg.flags = 0; /* Write transaction */
msg.buffer = data; /* Transfer from this address */
msg.length = 1; /* Send one byte */
/* Perform the transfer */
ret = I2C_TRANSFER(priv->i2c, &msg, 1);
if (ret < 0)
{
lcderr("ERROR: I2C_TRANSFER failed: %d\n", ret);
}
}
/****************************************************************************
* Name: ht16k33_write_data
*
* Description:
* Write a Data command to HT16K33
*
****************************************************************************/
static inline void ht16k33_write_data(FAR struct ht16k33_dev_s *priv,
int dev_id, uint8_t cmd,
uint8_t *values, int nbytes)
{
struct i2c_msg_s msg;
uint8_t data[16];
int ret;
int i;
/* Prepare data to send */
data[0] = cmd;
for (i = 0; i < nbytes; i++)
{
data[i + 1] = values[i];
}
/* Setup the message to write data to HT16K33 */
msg.frequency = CONFIG_HT16K33_I2C_FREQ; /* I2C frequency */
msg.addr = HT16K33_I2C_ADDR + dev_id; /* 7-bit address */
msg.flags = 0; /* Write transaction */
msg.buffer = data; /* Transfer from here */
msg.length = nbytes + 1; /* Send cmd + nbytes */
/* Perform the transfer */
ret = I2C_TRANSFER(priv->i2c, &msg, 1);
if (ret < 0)
{
lcderr("ERROR: I2C_TRANSFER failed: %d\n", ret);
}
}
static inline void ht16k33_setcontrast(FAR struct ht16k33_dev_s *priv,
int dev_id, int8_t contrast)
{
int i;
if (contrast < HT16K33_CONTRAST_MIN)
{
contrast = HT16K33_CONTRAST_MIN;
}
else if (contrast > HT16K33_CONTRAST_MAX)
{
contrast = HT16K33_CONTRAST_MAX;
}
for (i = 0; i < CONFIG_LCD_HT16K33_NUMBER_MODULES; i++)
{
ht16k33_write_cmd(priv, i, HT16K33_DIMMING_SET | (contrast & 0x0f));
}
}
/****************************************************************************
* Name: lcd_getdata
*
* Description:
* Simulate reading data from LCD, we are reading from internal buffer
*
****************************************************************************/
static inline uint8_t lcd_getdata(FAR struct ht16k33_dev_s *priv)
{
uint8_t data;
data = priv->buffer[priv->row * priv->col];
return data;
}
/****************************************************************************
* Name: rc2addr
*
* Description:
* This converts a row/column pair to a screen memory address.
*
****************************************************************************/
static inline uint8_t rc2addr(FAR struct ht16k33_dev_s *priv)
{
/* Each module has 4 digits they correspond to these columns:
*
* col0: 0x00 - 0x01, col1: 0x02 - 0x03,
* col2: 0x04 - 0x05, col3: 0x06 - 0x07
*/
return (priv->col % 4) * 0x02;
}
/****************************************************************************
* Name: addr2rc
*
* Description:
* This converts a screen memory address to a row/column pair.
*
****************************************************************************/
static inline void addr2rc(FAR struct ht16k33_dev_s *priv, uint8_t addr,
FAR uint8_t *row, FAR uint8_t *col)
{
*row = 0;
*col = addr / 2;
}
/****************************************************************************
* Name: lcd_set_curpos
*
* Description:
* This sets the cursor position based on row, column addressing.
*
* Input Parameters:
* priv - device instance
*
****************************************************************************/
static void lcd_set_curpos(FAR struct ht16k33_dev_s *priv)
{
uint8_t addr;
int dev_id;
addr = rc2addr(priv);
dev_id = priv->col / 4;
/* Define the memory address position */
ht16k33_write_cmd(priv, dev_id, HT16K33_DISP_DATA_ADDR | addr);
}
/****************************************************************************
* Name: lcd_putdata
*
* Description:
* Write a byte to the LCD and update column/row position
*
****************************************************************************/
static inline void lcd_putdata(FAR struct ht16k33_dev_s *priv, uint8_t data)
{
uint8_t segment[2];
uint8_t addr;
uint8_t cmd;
int dev_id;
/* Get current display memory position */
addr = rc2addr(priv);
/* Setup the memory command */
cmd = HT16K33_DISP_DATA_ADDR | addr;
/* Get the segments setting */
segment[0] = asciito14seg[data - 32] & 0xff;
segment[1] = (asciito14seg[data - 32] & 0xff00) >> 8;
dev_id = priv->col / 4;
/* Send data to display */
ht16k33_write_data(priv, dev_id, cmd, segment, 2);
/* Save it in the buffer because we cannot read from display */
priv->buffer[priv->col * priv->row] = data;
/* Update col/row positions */
priv->col++;
if (priv->col >= HT16K33_MAX_COL)
{
priv->col = 0;
priv->row++;
}
if (priv->row >= HT16K33_MAX_ROW)
{
priv->pendscroll = true;
priv->row = HT16K33_MAX_ROW - 1;
}
/* Update cursor position */
lcd_set_curpos(priv);
}
/****************************************************************************
* Name: lcd_scroll_up
*
* Description:
* Scroll the display up, and clear the new (last) line.
*
****************************************************************************/
static void lcd_scroll_up(FAR struct ht16k33_dev_s *priv)
{
FAR uint8_t *data;
int currow;
int curcol;
data = kmm_malloc(HT16K33_MAX_COL);
if (NULL == data)
{
lcdinfo("Failed to allocate buffer in lcd_scroll_up()\n");
return;
}
for (currow = 1; currow < HT16K33_MAX_ROW; ++currow)
{
priv->row = currow;
for (curcol = 0; curcol < HT16K33_MAX_COL; ++curcol)
{
priv->col = curcol;
data[curcol] = lcd_getdata(priv);
}
priv->col = 0;
priv->row = currow - 1;
lcd_set_curpos(priv);
for (curcol = 0; curcol < HT16K33_MAX_COL; ++curcol)
{
lcd_putdata(priv, data[curcol]);
}
}
ht16k33_clear_display(priv);
kmm_free(data);
}
/****************************************************************************
* Name: ht16k33_clear_display
*
* Description:
* Clear the display writing space (' ') to all positions
*
****************************************************************************/
static void ht16k33_clear_display(FAR struct ht16k33_dev_s *priv)
{
int curcol;
priv->col = 0;
priv->row = HT16K33_MAX_ROW - 1;
lcd_set_curpos(priv);
for (curcol = 0; curcol < HT16K33_MAX_COL; ++curcol)
{
lcd_putdata(priv, ' ');
}
priv->col = 0;
priv->row = HT16K33_MAX_ROW - 1;
lcd_set_curpos(priv);
}
/****************************************************************************
* Name: lcd_codec_action
*
* Description:
* Perform an 'action' as per the Segment LCD codec.
*
* Input Parameters:
* priv - device instance
* code - SLCD code action code
* count - count param for those actions that take it
*
****************************************************************************/
static void lcd_codec_action(FAR struct ht16k33_dev_s *priv,
enum slcdcode_e code, uint8_t count)
{
switch (code)
{
/* Erasure */
case SLCDCODE_BACKDEL: /* Backspace (backward delete)
* N characters
*/
{
if (count <= 0) /* we need to delete more 0 positions */
{
break;
}
else
{
if (count > priv->col) /* saturate to preceding columns
* available
*/
{
count = priv->col;
}
priv->col = priv->col - count;
lcd_set_curpos(priv);
}
/* ... and conscientiously fall through to next case ... */
}
case SLCDCODE_FWDDEL: /* Delete (forward delete) N characters
* moving text
*/
{
if (count <= 0) /* we need to delete more 0 positions */
{
break;
}
else
{
uint8_t start;
uint8_t end;
uint8_t i;
uint8_t data;
start = priv->col + count;
if (start >= HT16K33_MAX_COL) /* nothing left */
{
break;
}
end = start + count;
if (end > HT16K33_MAX_COL) /* saturate */
{
end = HT16K33_MAX_COL;
}
for (i = priv->col; i < end; ++start, ++i) /* like memmove */
{
priv->col = start;
lcd_set_curpos(priv);
data = lcd_getdata(priv);
priv->col = i;
lcd_set_curpos(priv);
lcd_putdata(priv, data);
}
for (; i < HT16K33_MAX_COL; ++i) /* much like memset */
{
lcd_putdata(priv, ' ');
}
lcd_set_curpos(priv);
}
}
break;
case SLCDCODE_ERASE: /* Erase N characters from the cursor
* position
*/
if (count > 0)
{
uint8_t end;
uint8_t i;
end = priv->col + count;
if (end > HT16K33_MAX_COL)
{
end = HT16K33_MAX_COL;
}
for (i = priv->col; i < end; ++i)
{
lcd_putdata(priv, ' ');
}
lcd_set_curpos(priv);
}
break;
case SLCDCODE_CLEAR: /* Home the cursor and erase the entire
* display
*/
{
/* ht16k33_write_cmd(priv, HT16K33_CLEAR_DISPLAY); */
}
break;
case SLCDCODE_ERASEEOL: /* Erase from the cursor position to
* the end of line
*/
{
uint8_t i;
for (i = priv->col; i < HT16K33_MAX_COL; ++i)
{
lcd_putdata(priv, ' ');
}
lcd_set_curpos(priv);
}
break;
/* Cursor movement */
case SLCDCODE_LEFT: /* Cursor left by N characters */
{
if (count > priv->col)
{
priv->col = 0;
}
else
{
priv->col -= count;
}
lcd_set_curpos(priv);
}
break;
case SLCDCODE_RIGHT: /* Cursor right by N characters */
{
priv->col += count;
if (priv->col >= HT16K33_MAX_COL)
{
priv->col = HT16K33_MAX_COL - 1;
}
lcd_set_curpos(priv);
}
break;
case SLCDCODE_UP: /* Cursor up by N lines */
{
if (count > priv->row)
{
priv->row = 0;
}
else
{
priv->row -= count;
}
lcd_set_curpos(priv);
}
break;
case SLCDCODE_DOWN: /* Cursor down by N lines */
{
priv->row += count;
if (priv->row >= HT16K33_MAX_ROW)
{
priv->row = HT16K33_MAX_ROW - 1;
}
lcd_set_curpos(priv);
}
break;
case SLCDCODE_HOME: /* Cursor home */
{
priv->col = 0;
lcd_set_curpos(priv);
}
break;
case SLCDCODE_END: /* Cursor end */
{
priv->col = HT16K33_MAX_COL - 1;
lcd_set_curpos(priv);
}
break;
case SLCDCODE_PAGEUP: /* Cursor up by N pages */
case SLCDCODE_PAGEDOWN: /* Cursor down by N pages */
break; /* Not supportable on this SLCD */
/* Blinking */
case SLCDCODE_BLINKSTART: /* Start blinking with current cursor
* position
*/
ht16k33_write_cmd(priv, 0, HT16K33_DISPLAY_SETUP |
DISPLAY_SETUP_BLINK_2HZ);
break;
case SLCDCODE_BLINKEND: /* End blinking after the current cursor
* position
*/
case SLCDCODE_BLINKOFF: /* Turn blinking off */
ht16k33_write_cmd(priv, 0, HT16K33_DISPLAY_SETUP |
DISPLAY_SETUP_BLINK_OFF);
break; /* Not implemented */
/* These are actually unreportable errors */
default:
case SLCDCODE_NORMAL: /* Not a special keycode */
break;
}
}
/****************************************************************************
* Name: lcd_init
*
* Description:
* perform the initialization sequence to get the LCD into a known state.
*
****************************************************************************/
static void lcd_init(FAR struct ht16k33_dev_s *priv)
{
uint8_t data;
int i;
for (i = 0; i < CONFIG_LCD_HT16K33_NUMBER_MODULES; i++)
{
/* Initialize the Display: Turn ON Oscillator */
data = HT16K33_SYSTEM_SETUP | SYSTEM_SETUP_OSC_ON;
ht16k33_write_cmd(priv, i, data);
/* Clear display */
ht16k33_clear_display(priv);
/* Display ON */
data = HT16K33_DISPLAY_SETUP | DISPLAY_SETUP_DISP_ON;
ht16k33_write_cmd(priv, i, data);
}
}
/****************************************************************************
* Name: lcd_curpos_to_fpos
*
* Description:
* Convert a screen cursor pos (row,col) to a file logical offset. This
* includes 'synthesized' line feeds at the end of screen lines.
*
****************************************************************************/
static void lcd_curpos_to_fpos(FAR struct ht16k33_dev_s *priv,
uint8_t row, uint8_t col, FAR off_t *fpos)
{
/* the logical file position is the linear position plus any synthetic LF */
*fpos = (row * HT16K33_MAX_COL) + col + row;
}
/****************************************************************************
* Name: ht16k33_read
****************************************************************************/
static ssize_t ht16k33_read(FAR struct file *filep, FAR char *buffer,
size_t buflen)
{
return -ENOSYS;
}
/****************************************************************************
* Name: ht16k33_write
****************************************************************************/
static ssize_t ht16k33_write(FAR struct file *filep, FAR const char *buffer,
size_t buflen)
{
FAR struct inode *inode = filep->f_inode;
FAR struct ht16k33_dev_s *priv = inode->i_private;
struct lib_meminstream_s instream;
struct slcdstate_s state;
enum slcdret_e result;
uint8_t ch;
uint8_t count;
nxmutex_lock(&priv->lock);
/* Initialize the stream for use with the SLCD CODEC */
lib_meminstream(&instream, buffer, buflen);
/* Now decode and process every byte in the input buffer */
memset(&state, 0, sizeof(struct slcdstate_s));
while ((result = slcd_decode(&instream.common,
&state, &ch, &count)) != SLCDRET_EOF)
{
/* Is there some pending scroll? */
if (priv->pendscroll)
{
lcd_scroll_up(priv);
priv->pendscroll = false;
}
if (result == SLCDRET_CHAR) /* A normal character was returned */
{
/* Check for ASCII control characters */
if (ch == ASCII_TAB)
{
/* TODO: define what TAB should do */
}
else if (ch == ASCII_VT)
{
/* Turn the backlight on */
/* TODO: lcd_backlight(priv, true); */
}
else if (ch == ASCII_FF)
{
/* Turn the backlight off */
/* TODO: lcd_backlight(priv, false); */
}
else if (ch == ASCII_CR)
{
/* Perform a Home */
priv->col = 0;
lcd_set_curpos(priv);
}
else if (ch == ASCII_SO)
{
/* TODO: We don't have cursor */
}
else if (ch == ASCII_SI)
{
/* Perform the re-initialize */
lcd_init(priv);
priv->row = 0;
priv->col = 0;
}
else if (ch == ASCII_LF)
{
/* unixian line term; go to start of next line */
priv->row += 1;
if (priv->row >= HT16K33_MAX_ROW)
{
priv->pendscroll = true;
priv->row = HT16K33_MAX_ROW - 1;
}
priv->col = 0;
lcd_set_curpos(priv);
}
else if (ch == ASCII_BS)
{
/* Perform the backward deletion */
lcd_codec_action(priv, SLCDCODE_BACKDEL, 1);
}
else if (ch == ASCII_DEL)
{
/* Perform the forward deletion */
lcd_codec_action(priv, SLCDCODE_FWDDEL, 1);
}
else
{
/* Just print it! */
lcd_putdata(priv, ch);
}
}
else /* (result == SLCDRET_SPEC) */ /* A special SLCD action was returned */
{
lcd_codec_action(priv, (enum slcdcode_e)ch, count);
}
}
/* Wherever we wound up, update our logical file pos to reflect it */
lcd_curpos_to_fpos(priv, priv->row, priv->col, &filep->f_pos);
nxmutex_unlock(&priv->lock);
return buflen;
}
/****************************************************************************
* Name: ht16k33_seek
*
* Description:
* Seek the logical file pointer to the specified position. This is
* probably not very interesting except possibly for (SEEK_SET, 0) to
* rewind the pointer for a subsequent read().
* The file pointer is logical, and includes synthesized LF chars at the
* end of the display lines.
*
****************************************************************************/
static off_t ht16k33_seek(FAR struct file *filep, off_t offset, int whence)
{
FAR struct inode *inode = filep->f_inode;
FAR struct ht16k33_dev_s *priv =
inode->i_private;
off_t maxpos;
off_t pos;
nxmutex_lock(&priv->lock);
maxpos = HT16K33_MAX_ROW * HT16K33_MAX_COL + (HT16K33_MAX_ROW - 1);
pos = filep->f_pos;
switch (whence)
{
case SEEK_CUR:
pos += offset;
if (pos > maxpos)
{
pos = maxpos;
}
else if (pos < 0)
{
pos = 0;
}
filep->f_pos = pos;
break;
case SEEK_SET:
pos = offset;
if (pos > maxpos)
{
pos = maxpos;
}
else if (pos < 0)
{
pos = 0;
}
filep->f_pos = pos;
break;
case SEEK_END:
pos = maxpos + offset;
if (pos > maxpos)
{
pos = maxpos;
}
else if (pos < 0)
{
pos = 0;
}
filep->f_pos = pos;
break;
default:
/* Return EINVAL if the whence argument is invalid */
pos = (off_t)-EINVAL;
break;
}
nxmutex_unlock(&priv->lock);
return pos;
}
/****************************************************************************
* Name: ht16k33_ioctl
*
* Description:
* Perform device operations that are outside the standard I/O model.
*
****************************************************************************/
static int ht16k33_ioctl(FAR struct file *filep, int cmd,
unsigned long arg)
{
switch (cmd)
{
case SLCDIOC_GETATTRIBUTES: /* Get the attributes of the SLCD */
{
FAR struct slcd_attributes_s *attr =
(FAR struct slcd_attributes_s *)((uintptr_t)arg);
lcdinfo("SLCDIOC_GETATTRIBUTES:\n");
if (!attr)
{
return -EINVAL;
}
attr->nrows = HT16K33_MAX_ROW;
attr->ncolumns = HT16K33_MAX_COL;
attr->nbars = 0;
attr->maxcontrast = 0;
attr->maxbrightness = 16; /* 'brightness' for us is the backlight */
}
break;
case SLCDIOC_CURPOS: /* Get the SLCD cursor position */
{
FAR struct inode *inode = filep->f_inode;
FAR struct ht16k33_dev_s *priv =
inode->i_private;
FAR struct slcd_curpos_s *attr =
(FAR struct slcd_curpos_s *)((uintptr_t)arg);
attr->row = priv->row;
attr->column = priv->col;
}
break;
case SLCDIOC_GETBRIGHTNESS: /* Get the current brightness setting */
{
FAR struct inode *inode = filep->f_inode;
FAR struct ht16k33_dev_s *priv =
inode->i_private;
nxmutex_lock(&priv->lock);
*(FAR int *)((uintptr_t)arg) = 1; /* Hardcoded */
nxmutex_unlock(&priv->lock);
}
break;
case SLCDIOC_SETBRIGHTNESS: /* Set the brightness to a new value */
{
FAR struct inode *inode = filep->f_inode;
FAR struct ht16k33_dev_s *priv =
inode->i_private;
nxmutex_lock(&priv->lock);
ht16k33_setcontrast(priv, 0, (uint8_t)arg);
nxmutex_unlock(&priv->lock);
}
break;
case SLCDIOC_SETBAR: /* Set bars on a bar display */
case SLCDIOC_GETCONTRAST: /* Get the current contrast setting */
case SLCDIOC_SETCONTRAST: /* Set the contrast to a new value */
default:
return -ENOTTY;
}
return OK;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: ht16k33_register
*
* Description:
* Register the HT16K33 character device as 'devpath'
*
* Input Parameters:
* devno - The device number to register. E.g., "/dev/slcd0"
* i2c - An instance of the I2C interface to use to communicate with
* HT16K33
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure.
*
****************************************************************************/
int ht16k33_register(int devno, FAR struct i2c_master_s *i2c)
{
FAR struct ht16k33_dev_s *priv;
char devname[DEVNAME_FMTLEN];
int ret;
/* Initialize the HT16K33 device structure */
priv = (FAR struct ht16k33_dev_s *)
kmm_malloc(sizeof(struct ht16k33_dev_s));
if (!priv)
{
snerr("ERROR: Failed to allocate instance\n");
return -ENOMEM;
}
/* Setup priv with initial values */
priv->i2c = i2c;
priv->col = 0;
priv->row = 0;
priv->pendscroll = false;
nxmutex_init(&priv->lock);
/* Initialize the display */
lcd_init(priv);
/* Create the character device name */
snprintf(devname, sizeof(devname), DEVNAME_FMT, devno);
/* Register the driver */
ret = register_driver(devname, &g_ht16k33fops, 0666, priv);
if (ret < 0)
{
snerr("ERROR: Failed to register driver: %d\n", ret);
nxmutex_destroy(&priv->lock);
kmm_free(priv);
}
return ret;
}
#endif /* CONFIG_SPI && CONFIG_HT16K33 */