936df1bcb5
Squashed commit of the following:
Change all calls to usleep() in the OS proper to calls to nxsig_usleep()
sched/signal: Add a new OS internal function nxsig_usleep() that is functionally equivalent to usleep() but does not cause a cancellaption point and does not modify the errno variable.
sched/signal: Add a new OS internal function nxsig_sleep() that is functionally equivalent to sleep() but does not cause a cancellaption point.
1617 lines
45 KiB
C
1617 lines
45 KiB
C
/****************************************************************************
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* drivers/lcd/pcf8574_lcd_backpack.c
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*
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* Copyright (C) 2016-2017 Gregory Nutt. All rights reserved.
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* Author: dev@ziggurat29.com
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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* 3. Neither the name NuttX nor the names of its contributors may be
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* used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*
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****************************************************************************/
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <nuttx/config.h>
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#include <poll.h>
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#include <string.h>
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#include <errno.h>
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#include <debug.h>
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#include <nuttx/kmalloc.h>
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#include <nuttx/signal.h>
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#include <nuttx/ascii.h>
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#include <nuttx/fs/fs.h>
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#include <nuttx/lcd/slcd_codec.h>
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#include <nuttx/lcd/pcf8574_lcd_backpack.h>
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#ifndef CONFIG_LIB_SLCDCODEC
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# error please also select Library Routines, Segment LCD CODEC
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#endif
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/****************************************************************************
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* Pre-processor Definitions
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****************************************************************************/
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/* The PCF8574 is a 100 KHz device */
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#define I2C_FREQ 100000
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/* timing characteristics of the LCD interface */
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#define DELAY_US_NYBBLE0 20
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#define DELAY_US_NYBBLE1 10
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#define DELAY_US_WRITE 40
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#define DELAY_US_HOMECLEAR 1500
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/* HD44780 commands */
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#define CMD_CLEAR 0x01
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#define CMD_HOME 0x02
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#define CMD_CURSOR_ON_SOLID 0x0e
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#define CMD_CURSOR_OFF 0x0c
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#define CMD_CURSOR_ON_BLINK 0x0f
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#define CMD_SET_CGADDR 0x40
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#define CMD_SET_DDADDR 0x80
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#define MAX_OPENCNT (255) /* Limit of uint8_t */
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/****************************************************************************
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* Private Types
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****************************************************************************/
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struct pcf8574_lcd_dev_s
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{
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FAR struct i2c_master_s *i2c; /* I2C interface */
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struct pcf8574_lcd_backpack_config_s cfg; /* gpio configuration */
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uint8_t bl_bit; /* current backlight bit */
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uint8_t refs; /* Number of references */
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uint8_t unlinked; /* We are unlinked, so teardown on last close */
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sem_t sem_excl; /* mutex */
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};
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struct lcd_instream_s
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{
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struct lib_instream_s stream;
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FAR const char *buffer;
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ssize_t nbytes;
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};
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/****************************************************************************
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* Private Function Prototypes
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****************************************************************************/
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/* Character driver methods */
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static int pcf8574_lcd_open(FAR struct file *filep);
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static int pcf8574_lcd_close(FAR struct file *filep);
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static ssize_t pcf8574_lcd_read(FAR struct file *filep, FAR char *buffer,
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size_t buflen);
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static ssize_t pcf8574_lcd_write(FAR struct file *filep,
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FAR const char *buffer, size_t buflen);
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static off_t pcf8574_lcd_seek(FAR struct file *filep, off_t offset, int whence);
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static int pcf8574_lcd_ioctl(FAR struct file *filep, int cmd,
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unsigned long arg);
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#ifndef CONFIG_DISABLE_POLL
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static int pcf8574lcd_poll(FAR struct file *filep, FAR struct pollfd *fds,
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bool setup);
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#endif
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#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
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static int pcf8574_lcd_unlink(FAR struct inode *inode);
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#endif
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/****************************************************************************
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* Private Data
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****************************************************************************/
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static const struct file_operations g_pcf8574_lcd_fops =
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{
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pcf8574_lcd_open, /* open */
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pcf8574_lcd_close, /* close */
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pcf8574_lcd_read, /* read */
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pcf8574_lcd_write, /* write */
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pcf8574_lcd_seek, /* seek */
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pcf8574_lcd_ioctl, /* ioctl */
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#ifndef CONFIG_DISABLE_POLL
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pcf8574lcd_poll, /* poll */
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#endif
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#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
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pcf8574_lcd_unlink /* unlink */
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#endif
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};
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/****************************************************************************
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* Private Functions
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****************************************************************************/
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/****************************************************************************
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* Name: pca8574_write
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*
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* Description:
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* primitive I2C write operation for the PCA8574, which is the IO expander
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* device used on the board. The board essentially byte-bangs the
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* parallel interface in nybble mode much as one might with a conventional
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* GPIO based interface. The I2C interface simply sets the state of the
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* 8 IO lines to control the 4 data, 3 control, and one for backlight,
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* signals.
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*
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****************************************************************************/
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static void pca8574_write(FAR struct pcf8574_lcd_dev_s *priv, uint8_t data)
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{
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struct i2c_config_s config;
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int ret;
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/* Set up the I2C configuration */
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config.frequency = I2C_FREQ;
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config.address = priv->cfg.addr;
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config.addrlen = 7;
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/* Write the value */
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ret = i2c_write(priv->i2c, &config, &data, 1);
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if (ret < 0)
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{
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lcdinfo("pca8574_write() failed: %d\n", ret);
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return;
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}
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return;
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}
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/****************************************************************************
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* Name: pca8574_read
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*
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* Description:
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* primitive I2C read operation for the PCA8574, which is the IO expander
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* device used on the board. The PCF8574 is 'interesting' in that it doesn't
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* really have a data direction register, but instead the outputs are current-
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* limited when high, so by setting an IO line high, you are also making it
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* an input. Consequently, before using this method, you'll need to perform a
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* pca8574_write() setting the bits you are interested in reading to 1's,
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* then call this method.
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*
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****************************************************************************/
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static int pca8574_read(FAR struct pcf8574_lcd_dev_s *priv, uint8_t* data)
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{
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struct i2c_config_s config;
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int ret;
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/* Set up the I2C configuration */
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config.frequency = I2C_FREQ;
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config.address = priv->cfg.addr;
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config.addrlen = 7;
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/* Read the value */
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ret = i2c_read(priv->i2c, &config, data, 1);
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if (ret < 0)
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{
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lcdinfo("pca8574_read() failed: %d\n", ret);
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}
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return ret;
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}
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/****************************************************************************
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* Name: lcd_backlight
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*
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* Description:
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* turn on, or off, the LCD backlight
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*
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****************************************************************************/
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static void lcd_backlight(FAR struct pcf8574_lcd_dev_s *priv, bool blOn)
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{
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uint8_t data;
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data = ((blOn && priv->cfg.bl_active_high) ||
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(!blOn && !priv->cfg.bl_active_high)) ? (1 << priv->cfg.bl) : 0;
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pca8574_write(priv, data);
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priv->bl_bit = data;
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}
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/****************************************************************************
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* Name: rc2addr
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*
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* Description:
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* This converts a row/column pair to a screen memory address.
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*
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****************************************************************************/
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static inline uint8_t rc2addr(FAR struct pcf8574_lcd_dev_s *priv,
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uint8_t row, uint8_t col)
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{
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if (row < 2)
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{
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/* 1 and 2 line displays are simple; line0 @ 0x00, line1 @ 0x40 */
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return row * 0x40 + col;
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}
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else
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{
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/* 4 line displays are intersting; third line really is a continuation
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* of first line, and fourth line is a continuation of second.
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*/
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return (row - 2) * 0x40 + (col + priv->cfg.cols);
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}
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}
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/****************************************************************************
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* Name: addr2rc
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*
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* Description:
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* This converts a screen memory address to a row/column pair.
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*
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****************************************************************************/
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static inline void addr2rc(FAR struct pcf8574_lcd_dev_s *priv,
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uint8_t addr, uint8_t* row, uint8_t* col)
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{
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*row = addr / 0x40;
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*col = addr % 0x40;
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if (*col >= priv->cfg.cols)
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{
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/* 4 line displays have third and fourth lines really as continuation
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* of first and second.
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*/
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*row += 2;
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*col -= priv->cfg.cols;
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}
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}
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/****************************************************************************
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* Name: prepare_nybble
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*
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* Description:
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* This is a bit tedious, but scramble the bits of the nybble into position
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* as per this board's particular wiring. Most boards are either on the
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* top four bits, or bottom four, so a shift would do typically in those
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* cases, but this gives us ultimate flexibility.
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*
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****************************************************************************/
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uint8_t prepare_nybble(FAR struct pcf8574_lcd_dev_s *priv, uint8_t nybble)
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{
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uint8_t lcddata = 0;
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if (nybble & 0x08)
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{
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lcddata |= (1 << priv->cfg.d7);
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}
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if (nybble & 0x04)
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{
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lcddata |= (1 << priv->cfg.d6);
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}
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if (nybble & 0x02)
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{
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lcddata |= (1 << priv->cfg.d5);
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}
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if (nybble & 0x01)
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{
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lcddata |= (1 << priv->cfg.d4);
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}
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return lcddata;
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}
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/****************************************************************************
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* Name: unprepare_nybble
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*
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* Description:
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* This is the opposite of prepare_nybble(), and is used to unscramble bits
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* when reading data from the display, as per board wiring.
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*
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****************************************************************************/
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uint8_t unprepare_nybble(FAR struct pcf8574_lcd_dev_s *priv, uint8_t lcddata)
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{
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uint8_t data = 0;
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if (lcddata & (1 << priv->cfg.d7))
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{
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data |= 0x08;
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}
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if (lcddata & (1 << priv->cfg.d6))
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{
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data |= 0x04;
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}
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if (lcddata & (1 << priv->cfg.d5))
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{
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data |= 0x02;
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}
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if (lcddata & (1 << priv->cfg.d4))
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{
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data |= 0x01;
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}
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return data;
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}
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/****************************************************************************
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* Name: latch_nybble
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*
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* Description:
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* Latch a nybble on the LCD bus. This is done for each of two halves of a
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* write operation in 4-bit mode. The 'rs' param is false for command
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* transfers, and true for data transfers.
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*
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****************************************************************************/
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static void latch_nybble(FAR struct pcf8574_lcd_dev_s *priv, uint8_t nybble,
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bool rs)
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{
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uint8_t lcddata;
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uint8_t en_bit;
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uint8_t rs_bit;
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en_bit = 1 << priv->cfg.en;
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rs_bit = rs ? (1 << priv->cfg.rs) : 0;
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/* Put the nybble, preserving backlight, reset R/~W and maybe RS */
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lcddata = prepare_nybble(priv, nybble) | priv->bl_bit | rs_bit;
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pca8574_write(priv, lcddata);
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/* Now set EN */
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lcddata |= en_bit;
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pca8574_write(priv, lcddata);
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up_udelay(DELAY_US_NYBBLE0); /* setup */
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/* Latch on EN falling edge */
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lcddata &= ~en_bit;
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pca8574_write(priv, lcddata);
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up_udelay(DELAY_US_NYBBLE1); /* hold */
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}
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|
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/****************************************************************************
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* Name: load_nybble
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*
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* Description:
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* Load a nybble from the LCD bus. This is done for each of two halves of a
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* read operation in 4-bit mode. The 'rs' param is false for command
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* transfers (the only one is to read status and the address register), and
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* true for data transfers.
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*
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****************************************************************************/
|
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|
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static uint8_t load_nybble(FAR struct pcf8574_lcd_dev_s *priv, bool rs)
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{
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uint8_t lcddata;
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uint8_t en_bit;
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uint8_t rs_bit;
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uint8_t rw_bit;
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uint8_t data;
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en_bit = 1 << priv->cfg.en;
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rs_bit = rs ? (1 << priv->cfg.rs) : 0;
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rw_bit = 1 << priv->cfg.rw;
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|
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/* Put highs on the data lines, preserve, set R/~W and maybe RS */
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|
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lcddata = prepare_nybble(priv, 0x0f) | priv->bl_bit | rw_bit | rs_bit;
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pca8574_write(priv, lcddata);
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|
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/* Now set EN */
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|
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lcddata |= en_bit;
|
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pca8574_write(priv, lcddata);
|
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up_udelay(DELAY_US_NYBBLE0); /* setup */
|
|
|
|
/* Now read the data */
|
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|
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pca8574_read(priv, &data);
|
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data = unprepare_nybble(priv, data);
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|
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/* Transaction completed on EN falling edge */
|
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|
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lcddata &= ~en_bit;
|
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pca8574_write(priv, lcddata);
|
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up_udelay(DELAY_US_NYBBLE1); /* hold */
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|
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return data;
|
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}
|
|
|
|
/****************************************************************************
|
|
* Name: lcd_putcmd
|
|
*
|
|
* Description:
|
|
* Write a command to the LCD. Most of the time this is done in nybble
|
|
* mode in two phases, but in special cases (like initialization) we do not
|
|
* do two phases.
|
|
*
|
|
****************************************************************************/
|
|
|
|
static void lcd_putcmd(FAR struct pcf8574_lcd_dev_s *priv, uint8_t data)
|
|
{
|
|
latch_nybble(priv, data >> 4, false);
|
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latch_nybble(priv, data, false);
|
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up_udelay(DELAY_US_WRITE);
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: lcd_putdata
|
|
*
|
|
* Description:
|
|
* Write a byte to the LCD. This is used both for screen data and for
|
|
* character generator data, depending on a previous command that selected
|
|
* which ever is the destination.
|
|
*
|
|
****************************************************************************/
|
|
|
|
static inline void lcd_putdata(FAR struct pcf8574_lcd_dev_s *priv,
|
|
uint8_t data)
|
|
{
|
|
latch_nybble(priv, data >> 4, true);
|
|
latch_nybble(priv, data, true);
|
|
up_udelay(DELAY_US_WRITE);
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: lcd_getdata
|
|
*
|
|
* Description:
|
|
* Read a data byte from the LCD.
|
|
*
|
|
****************************************************************************/
|
|
|
|
static inline uint8_t lcd_getdata(FAR struct pcf8574_lcd_dev_s *priv)
|
|
{
|
|
uint8_t data;
|
|
data = (load_nybble(priv, true) << 4) | load_nybble(priv, true);
|
|
return data;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: lcd_getcmd
|
|
*
|
|
* Description:
|
|
* Read a command byte from the LCD. There really is only one such read:
|
|
* get 'busy' status, and current address value.
|
|
*
|
|
****************************************************************************/
|
|
|
|
static inline uint8_t lcd_getcmd(FAR struct pcf8574_lcd_dev_s *priv)
|
|
{
|
|
uint8_t data;
|
|
data = (load_nybble(priv, false) << 4) | load_nybble(priv, false);
|
|
return data;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: lcd_read_busy_addr
|
|
*
|
|
* Description:
|
|
* Read the busy flag, and, optionally, the current value of the address
|
|
* register (data or character generator dependent on a previous command).
|
|
*
|
|
****************************************************************************/
|
|
|
|
static bool lcd_read_busy_addr(FAR struct pcf8574_lcd_dev_s *priv, uint8_t* addr)
|
|
{
|
|
uint8_t data = lcd_getcmd(priv);
|
|
|
|
if (NULL != addr)
|
|
{
|
|
*addr = data & 0x7f;
|
|
}
|
|
|
|
return (data & 0x80) ? true : false;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: lcd_init
|
|
*
|
|
* Description:
|
|
* perform the initialization sequence to get the LCD into a known state.
|
|
*
|
|
****************************************************************************/
|
|
|
|
static void lcd_init(FAR struct pcf8574_lcd_dev_s *priv)
|
|
{
|
|
/* Wait for more than 15 ms after Vcc for the LCD to stabilize */
|
|
|
|
nxsig_usleep(50000);
|
|
|
|
/* Perform the init sequence. This sequence of commands is constructed so
|
|
* that it will get the device into nybble mode irrespective of what state
|
|
* the device is currently in (could be 8 bit, 4 bit nyb 0, 4 bit nyb 1).
|
|
* By sending the 'set 8-bit mode' three times, we will definitely end up
|
|
* in 8 bit mode, and then we can reliably transition to 4 bit mode for
|
|
* the remainder of operations.
|
|
*/
|
|
|
|
/* Send Command 0x30, set 8-bit mode, and wait > 4.1 ms */
|
|
|
|
latch_nybble(priv, 0x30>>4, false);
|
|
nxsig_usleep(5000);
|
|
|
|
/* Send Command 0x30, set 8-bit mode, and wait > 100 us */
|
|
|
|
latch_nybble(priv, 0x30>>4, false);
|
|
nxsig_usleep(5000);
|
|
|
|
/* Send Command 0x30, set 8-bit mode */
|
|
|
|
latch_nybble(priv, 0x30>>4, false);
|
|
nxsig_usleep(200);
|
|
|
|
/* now Function set: Set interface to be 4 bits long (only 1 cycle write for the first time). */
|
|
|
|
latch_nybble(priv, 0x20>>4, false);
|
|
nxsig_usleep(5000);
|
|
|
|
/* Function set: DL=0;Interface is 4 bits, N=1 (2 Lines), F=0 (5x8 dots font) */
|
|
|
|
lcd_putcmd(priv, 0x28);
|
|
|
|
/* Display Off: D=0 (Display off), C=0 (Cursor Off), B=0 (Blinking Off) */
|
|
|
|
lcd_putcmd(priv, 0x08);
|
|
|
|
/* Display Clear */
|
|
|
|
lcd_putcmd(priv, CMD_CLEAR);
|
|
up_udelay(DELAY_US_HOMECLEAR); /* clear needs extra time */
|
|
|
|
/* Entry Mode Set: I/D=1 (Increment), S=0 (No shift) */
|
|
|
|
lcd_putcmd(priv, 0x06);
|
|
|
|
/* Display On, Cursor Off */
|
|
|
|
lcd_putcmd(priv, 0x0C);
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: lcd_create_char
|
|
*
|
|
* Description:
|
|
* This creates a custom character pattern. There can be 8 5x8 patterns.
|
|
* The bitmap proceeds top to bottom, msb-lsb, and is right justified (i.e.
|
|
* only bits 4-0 are used). By convention, you are meant to always leave the
|
|
* last line (byte) zero so that the cursor can use this line, but this is
|
|
* not strictly required.
|
|
*
|
|
* Parameters:
|
|
* priv - device instance
|
|
* idxchar - which character is being imaged; 0 - 7
|
|
* chardata - the character image bitmap; must be 8 bytes always
|
|
*
|
|
****************************************************************************/
|
|
|
|
static void lcd_create_char(FAR struct pcf8574_lcd_dev_s *priv,
|
|
uint8_t idxchar, const uint8_t *chardata)
|
|
{
|
|
int nIdx;
|
|
uint8_t addr;
|
|
|
|
(void)lcd_read_busy_addr(priv, &addr);
|
|
lcd_putcmd(priv, CMD_SET_CGADDR | (idxchar << 3)); /* set CGRAM address */
|
|
|
|
for (nIdx = 0; nIdx < 8; ++nIdx)
|
|
{
|
|
lcd_putdata(priv, chardata[nIdx]);
|
|
}
|
|
|
|
lcd_putcmd(priv, CMD_SET_DDADDR | addr); /* restore DDRAM address */
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: lcd_set_curpos
|
|
*
|
|
* Description:
|
|
* This sets the cursor position based on row, column addressing.
|
|
*
|
|
* Parameters:
|
|
* priv - device instance
|
|
* row - row position
|
|
* col - column position
|
|
*
|
|
****************************************************************************/
|
|
|
|
static void lcd_set_curpos(FAR struct pcf8574_lcd_dev_s *priv,
|
|
uint8_t row, uint8_t col)
|
|
{
|
|
uint8_t addr;
|
|
addr = rc2addr(priv, row, col);
|
|
lcd_putcmd(priv, CMD_SET_DDADDR | addr); /* set DDRAM address */
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: lcd_get_curpos
|
|
*
|
|
* Description:
|
|
* This gets the cursor position based on row, column addressing.
|
|
*
|
|
* Parameters:
|
|
* priv - device instance
|
|
* row - row position
|
|
* col - column position
|
|
*
|
|
****************************************************************************/
|
|
|
|
static void lcd_get_curpos(FAR struct pcf8574_lcd_dev_s *priv,
|
|
uint8_t *row, uint8_t *col)
|
|
{
|
|
uint8_t addr;
|
|
|
|
(void)lcd_read_busy_addr(priv, &addr);
|
|
addr2rc(priv, addr, row, col);
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: lcd_scroll_up
|
|
*
|
|
* Description:
|
|
* Scroll the display up, and clear the new (last) line.
|
|
*
|
|
****************************************************************************/
|
|
|
|
static void lcd_scroll_up(FAR struct pcf8574_lcd_dev_s *priv)
|
|
{
|
|
uint8_t *data;
|
|
int nRow;
|
|
int nCol;
|
|
|
|
data = (uint8_t *)malloc(priv->cfg.cols);
|
|
if (NULL == data)
|
|
{
|
|
lcdinfo("Failed to allocate buffer in lcd_scroll_up()\n");
|
|
return;
|
|
}
|
|
|
|
for (nRow = 1; nRow < priv->cfg.rows; ++nRow)
|
|
{
|
|
lcd_set_curpos(priv, nRow, 0);
|
|
for (nCol = 0; nCol < priv->cfg.cols; ++nCol)
|
|
{
|
|
data[nCol] = lcd_getdata(priv);
|
|
}
|
|
|
|
lcd_set_curpos(priv, nRow - 1, 0);
|
|
for (nCol = 0; nCol < priv->cfg.cols; ++nCol)
|
|
{
|
|
lcd_putdata(priv, data[nCol]);
|
|
}
|
|
}
|
|
|
|
lcd_set_curpos(priv, priv->cfg.rows - 1, 0);
|
|
for (nCol = 0; nCol < priv->cfg.cols; ++nCol)
|
|
{
|
|
lcd_putdata(priv, ' ');
|
|
}
|
|
|
|
lcd_set_curpos(priv, priv->cfg.rows - 1, 0);
|
|
|
|
free(data);
|
|
return;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: lcd_codec_action
|
|
*
|
|
* Description:
|
|
* Perform an 'action' as per the Segment LCD codec.
|
|
*
|
|
* 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 pcf8574_lcd_dev_s *priv,
|
|
enum slcdcode_e code, uint8_t count)
|
|
{
|
|
switch (code)
|
|
{
|
|
/* Erasure */
|
|
|
|
case SLCDCODE_BACKDEL: /* Backspace (backward delete) N characters */
|
|
{
|
|
if (count <= 0) /* silly case */
|
|
break;
|
|
|
|
else
|
|
{
|
|
uint8_t row;
|
|
uint8_t col;
|
|
|
|
lcd_get_curpos(priv, &row, &col);
|
|
if (count > col) /* saturate to preceding columns available */
|
|
{
|
|
count = col;
|
|
}
|
|
|
|
lcd_set_curpos(priv, row, col-count);
|
|
}
|
|
|
|
/* ... and conscientiously fall through to next case ... */
|
|
}
|
|
|
|
case SLCDCODE_FWDDEL: /* Delete (forward delete) N characters, moving text */
|
|
{
|
|
if (count <= 0) /* silly case */
|
|
{
|
|
break;
|
|
}
|
|
|
|
else
|
|
{
|
|
uint8_t row;
|
|
uint8_t col;
|
|
uint8_t start;
|
|
uint8_t end;
|
|
uint8_t nIdx;
|
|
uint8_t data;
|
|
|
|
lcd_get_curpos(priv, &row, &col);
|
|
start = col + count;
|
|
|
|
if (start >= priv->cfg.cols) /* silly case of nothing left */
|
|
{
|
|
break;
|
|
}
|
|
|
|
end = start + count;
|
|
if (end > priv->cfg.cols) /* saturate */
|
|
{
|
|
end = priv->cfg.cols;
|
|
}
|
|
|
|
for(nIdx = col; nIdx < end; ++start, ++nIdx) /* much like memmove */
|
|
{
|
|
lcd_set_curpos(priv, row, start);
|
|
data = lcd_getdata(priv);
|
|
lcd_set_curpos(priv, row, nIdx);
|
|
lcd_putdata(priv, data);
|
|
}
|
|
|
|
for(;nIdx < priv->cfg.cols; ++nIdx) /* much like memset */
|
|
{
|
|
lcd_putdata(priv, ' ');
|
|
}
|
|
|
|
lcd_set_curpos(priv, row, col);
|
|
}
|
|
}
|
|
break;
|
|
|
|
case SLCDCODE_ERASE: /* Erase N characters from the cursor position */
|
|
if (count > 0)
|
|
{
|
|
uint8_t row;
|
|
uint8_t col;
|
|
uint8_t end;
|
|
uint8_t nIdx;
|
|
|
|
lcd_get_curpos(priv, &row, &col);
|
|
end = col + count;
|
|
if (end > priv->cfg.cols)
|
|
{
|
|
end = priv->cfg.cols;
|
|
}
|
|
|
|
for (nIdx = col; nIdx < end; ++nIdx)
|
|
{
|
|
lcd_putdata(priv, ' ');
|
|
}
|
|
|
|
lcd_set_curpos(priv, row, col);
|
|
}
|
|
break;
|
|
|
|
case SLCDCODE_CLEAR: /* Home the cursor and erase the entire display */
|
|
{
|
|
lcd_putcmd(priv, CMD_CLEAR);
|
|
up_udelay(DELAY_US_HOMECLEAR); /* clear needs extra time */
|
|
}
|
|
break;
|
|
|
|
case SLCDCODE_ERASEEOL: /* Erase from the cursor position to the end of line */
|
|
{
|
|
uint8_t row;
|
|
uint8_t col;
|
|
uint8_t nIdx;
|
|
|
|
lcd_get_curpos(priv, &row, &col);
|
|
|
|
for (nIdx = col; nIdx < priv->cfg.cols; ++nIdx)
|
|
{
|
|
lcd_putdata(priv, ' ');
|
|
}
|
|
|
|
lcd_set_curpos(priv, row, col);
|
|
}
|
|
break;
|
|
|
|
/* Cursor movement */
|
|
|
|
case SLCDCODE_LEFT: /* Cursor left by N characters */
|
|
{
|
|
uint8_t row;
|
|
uint8_t col;
|
|
|
|
lcd_get_curpos(priv, &row, &col);
|
|
if (count > col)
|
|
{
|
|
col = 0;
|
|
}
|
|
else
|
|
{
|
|
col -= count;
|
|
}
|
|
|
|
lcd_set_curpos(priv, row, col);
|
|
}
|
|
break;
|
|
|
|
case SLCDCODE_RIGHT: /* Cursor right by N characters */
|
|
{
|
|
uint8_t row;
|
|
uint8_t col;
|
|
|
|
lcd_get_curpos(priv, &row, &col);
|
|
col += count;
|
|
if (col >= priv->cfg.cols)
|
|
{
|
|
col = priv->cfg.cols-1;
|
|
}
|
|
|
|
lcd_set_curpos(priv, row, col);
|
|
}
|
|
break;
|
|
|
|
case SLCDCODE_UP: /* Cursor up by N lines */
|
|
{
|
|
uint8_t row;
|
|
uint8_t col;
|
|
|
|
lcd_get_curpos(priv, &row, &col);
|
|
if (count > row)
|
|
{
|
|
row = 0;
|
|
}
|
|
else
|
|
{
|
|
row -= count;
|
|
}
|
|
|
|
lcd_set_curpos(priv, row, col);
|
|
}
|
|
break;
|
|
|
|
case SLCDCODE_DOWN: /* Cursor down by N lines */
|
|
{
|
|
uint8_t row;
|
|
uint8_t col;
|
|
|
|
lcd_get_curpos(priv, &row, &col);
|
|
row += count;
|
|
if (row >= priv->cfg.rows)
|
|
{
|
|
row = priv->cfg.rows - 1;
|
|
}
|
|
|
|
lcd_set_curpos(priv, row, col);
|
|
}
|
|
break;
|
|
|
|
case SLCDCODE_HOME: /* Cursor home */
|
|
{
|
|
uint8_t row;
|
|
uint8_t col;
|
|
|
|
lcd_get_curpos(priv, &row, &col);
|
|
lcd_set_curpos(priv, row, 0);
|
|
}
|
|
break;
|
|
|
|
case SLCDCODE_END: /* Cursor end */
|
|
{
|
|
uint8_t row;
|
|
uint8_t col;
|
|
|
|
lcd_get_curpos(priv, &row, &col);
|
|
lcd_set_curpos(priv, row, priv->cfg.cols - 1);
|
|
}
|
|
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 */
|
|
lcd_putcmd(priv, CMD_CURSOR_ON_BLINK);
|
|
break;
|
|
|
|
case SLCDCODE_BLINKEND: /* End blinking after the current cursor position */
|
|
case SLCDCODE_BLINKOFF: /* Turn blinking off */
|
|
lcd_putcmd(priv, CMD_CURSOR_OFF);
|
|
break; /* Not implemented */
|
|
|
|
/* These are actually unreportable errors */
|
|
|
|
default:
|
|
case SLCDCODE_NORMAL: /* Not a special keycode */
|
|
break;
|
|
}
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: lcd_getstream
|
|
*
|
|
* Description:
|
|
* Get one character from the LCD codec stream.
|
|
*
|
|
****************************************************************************/
|
|
|
|
static int lcd_getstream(FAR struct lib_instream_s *instream)
|
|
{
|
|
FAR struct lcd_instream_s *lcdstream = (FAR struct lcd_instream_s *)instream;
|
|
|
|
if (lcdstream->nbytes > 0)
|
|
{
|
|
lcdstream->nbytes--;
|
|
lcdstream->stream.nget++;
|
|
return (int)*lcdstream->buffer++;
|
|
}
|
|
|
|
return EOF;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: lcd_fpos_to_curpos
|
|
*
|
|
* Description:
|
|
* Convert a file logical offset to a screen cursor pos (row,col). This
|
|
* discounts 'synthesized' line feeds at the end of screen lines.
|
|
*
|
|
****************************************************************************/
|
|
|
|
static void lcd_fpos_to_curpos(FAR struct pcf8574_lcd_dev_s *priv,
|
|
off_t fpos, uint8_t *row, uint8_t *col, bool* onlf)
|
|
{
|
|
int virtcols;
|
|
|
|
virtcols = (priv->cfg.cols + 1);
|
|
|
|
/* Determine if this is a 'virtual' position (on the synthetic LF) */
|
|
|
|
*onlf = (priv->cfg.cols == fpos % virtcols);
|
|
|
|
/* Adjust off any preceding synthetic LF's to get linear position */
|
|
|
|
fpos -= fpos / virtcols;
|
|
|
|
/* Compute row/col from linear position */
|
|
|
|
*row = fpos / priv->cfg.cols;
|
|
*col = fpos % priv->cfg.cols;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* 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 pcf8574_lcd_dev_s *priv,
|
|
uint8_t row, uint8_t col, off_t* fpos)
|
|
{
|
|
/* the logical file position is the linear position plus any synthetic LF */
|
|
|
|
*fpos = (row * priv->cfg.cols) + col + row;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: pcf8574_lcd_open
|
|
*
|
|
* Description:
|
|
* requisite device 'open' method; we don't do anything special
|
|
*
|
|
****************************************************************************/
|
|
|
|
static int pcf8574_lcd_open(FAR struct file *filep)
|
|
{
|
|
FAR struct inode *inode = filep->f_inode;
|
|
FAR struct pcf8574_lcd_dev_s *priv = (FAR struct pcf8574_lcd_dev_s *)inode->i_private;
|
|
|
|
/* Increment the reference count */
|
|
|
|
nxsem_wait(&priv->sem_excl);
|
|
if (priv->refs == MAX_OPENCNT)
|
|
{
|
|
return -EMFILE;
|
|
}
|
|
else
|
|
{
|
|
priv->refs++;
|
|
}
|
|
|
|
nxsem_post(&priv->sem_excl);
|
|
return OK;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: pcf8574_lcd_close
|
|
*
|
|
* Description:
|
|
* requisite device 'close' method; we don't do anything special
|
|
*
|
|
****************************************************************************/
|
|
|
|
static int pcf8574_lcd_close(FAR struct file *filep)
|
|
{
|
|
FAR struct inode *inode = filep->f_inode;
|
|
FAR struct pcf8574_lcd_dev_s *priv = (FAR struct pcf8574_lcd_dev_s *)inode->i_private;
|
|
int ret;
|
|
|
|
/* Decrement the reference count */
|
|
|
|
nxsem_wait(&priv->sem_excl);
|
|
|
|
if (priv->refs == 0)
|
|
{
|
|
ret = -EIO;
|
|
}
|
|
else
|
|
{
|
|
priv->refs--;
|
|
|
|
/* If we had previously unlinked, but there were open references at the
|
|
* time, we need to do the final teardown now.
|
|
*/
|
|
|
|
if (priv->refs == 0 && priv->unlinked)
|
|
{
|
|
/* We have no real teardown at present */
|
|
}
|
|
ret = OK;
|
|
}
|
|
|
|
nxsem_post(&priv->sem_excl);
|
|
return ret;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: pcf8574_lcd_read
|
|
*
|
|
* Description:
|
|
* This simply reads as much of the display memory as possible. This is
|
|
* generally not very interesting, but we do it in a way that allows us to
|
|
* 'cat' the LCD contents via the shell.
|
|
*
|
|
****************************************************************************/
|
|
|
|
static ssize_t pcf8574_lcd_read(FAR struct file *filep, FAR char *buffer,
|
|
size_t buflen)
|
|
{
|
|
FAR struct inode *inode = filep->f_inode;
|
|
FAR struct pcf8574_lcd_dev_s *priv = (FAR struct pcf8574_lcd_dev_s *)inode->i_private;
|
|
int nIdx;
|
|
uint8_t addr;
|
|
uint8_t row;
|
|
uint8_t col;
|
|
bool onlf;
|
|
|
|
nxsem_wait(&priv->sem_excl);
|
|
|
|
/* Get current cursor position so we can restore it */
|
|
|
|
(void)lcd_read_busy_addr(priv, &addr);
|
|
|
|
/* Convert file position to row/col address and position DDADDR there */
|
|
|
|
lcd_fpos_to_curpos(priv, filep->f_pos, &row, &col, &onlf);
|
|
lcd_set_curpos(priv, row, col);
|
|
|
|
/* Read as much of the display as possible */
|
|
|
|
nIdx = 0;
|
|
while (nIdx < buflen && row < priv->cfg.rows)
|
|
{
|
|
/* Synthesize end-of-line LF and advance to start of next row */
|
|
|
|
if (onlf)
|
|
{
|
|
/* Synthesize LF for all but last row */
|
|
|
|
if ( row < priv->cfg.rows-1)
|
|
{
|
|
buffer[nIdx] = '\x0a';
|
|
onlf = false;
|
|
++filep->f_pos;
|
|
++nIdx;
|
|
}
|
|
++row;
|
|
col = 0;
|
|
continue;
|
|
}
|
|
|
|
/* If we are at start of line we will need to update DDRAM address */
|
|
|
|
if (0 == col)
|
|
{
|
|
lcd_set_curpos(priv, row, 0);
|
|
}
|
|
|
|
buffer[nIdx] = lcd_getdata(priv);
|
|
|
|
++filep->f_pos;
|
|
++nIdx;
|
|
++col;
|
|
|
|
/* If we are now at the end of a line, we setup for the synthetic LF */
|
|
|
|
if (priv->cfg.cols == col)
|
|
{
|
|
onlf = true;
|
|
}
|
|
}
|
|
|
|
lcd_putcmd(priv, CMD_SET_DDADDR | addr); /* Restore DDRAM address */
|
|
|
|
nxsem_post(&priv->sem_excl);
|
|
return nIdx;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: pcf8574_lcd_write
|
|
*
|
|
* Description:
|
|
* Output a sequence of characters to the device.
|
|
*
|
|
****************************************************************************/
|
|
|
|
static ssize_t pcf8574_lcd_write(FAR struct file *filep,
|
|
FAR const char *buffer,
|
|
size_t buflen)
|
|
{
|
|
FAR struct inode *inode = filep->f_inode;
|
|
FAR struct pcf8574_lcd_dev_s *priv = (FAR struct pcf8574_lcd_dev_s *)inode->i_private;
|
|
struct lcd_instream_s instream;
|
|
uint8_t row;
|
|
uint8_t col;
|
|
struct slcdstate_s state;
|
|
enum slcdret_e result;
|
|
uint8_t ch;
|
|
uint8_t count;
|
|
|
|
nxsem_wait(&priv->sem_excl);
|
|
|
|
/* Initialize the stream for use with the SLCD CODEC */
|
|
|
|
instream.stream.get = lcd_getstream;
|
|
instream.stream.nget = 0;
|
|
instream.buffer = buffer;
|
|
instream.nbytes = buflen;
|
|
|
|
/* Get the current cursor position now; we'll keep track of it as we go */
|
|
|
|
lcd_get_curpos(priv, &row, &col);
|
|
|
|
/* Now decode and process every byte in the input buffer */
|
|
|
|
memset(&state, 0, sizeof(struct slcdstate_s));
|
|
while ((result = slcd_decode(&instream.stream, &state, &ch, &count)) != SLCDRET_EOF)
|
|
{
|
|
if (result == SLCDRET_CHAR) /* A normal character was returned */
|
|
{
|
|
/* Check for ASCII control characters */
|
|
|
|
if (ch == ASCII_TAB)
|
|
{
|
|
lcd_putcmd(priv, CMD_CURSOR_ON_BLINK);
|
|
}
|
|
else if (ch == ASCII_VT)
|
|
{
|
|
/* Turn the backlight on */
|
|
|
|
lcd_backlight(priv, true);
|
|
}
|
|
else if (ch == ASCII_FF)
|
|
{
|
|
/* Turn the backlight off */
|
|
|
|
lcd_backlight(priv, false);
|
|
}
|
|
else if (ch == ASCII_CR)
|
|
{
|
|
/* Perform a Home */
|
|
|
|
lcd_putcmd(priv, CMD_HOME);
|
|
up_udelay(DELAY_US_HOMECLEAR); /* home needs extra time */
|
|
row = 0;
|
|
col = 0;
|
|
}
|
|
else if (ch == ASCII_SO)
|
|
{
|
|
lcd_putcmd(priv, CMD_CURSOR_OFF);
|
|
}
|
|
else if (ch == ASCII_SI)
|
|
{
|
|
/* Perform the re-initialize */
|
|
|
|
lcd_init(priv);
|
|
row = 0;
|
|
col = 0;
|
|
}
|
|
else if (ch == ASCII_LF)
|
|
{
|
|
/* unixian line term; go to start of next line */
|
|
|
|
row += 1;
|
|
if (row >= priv->cfg.rows)
|
|
{
|
|
lcd_scroll_up(priv);
|
|
row = priv->cfg.rows - 1;
|
|
}
|
|
|
|
col = 0;
|
|
lcd_set_curpos(priv, row, col);
|
|
}
|
|
else if (ch == ASCII_BS)
|
|
{
|
|
/* Perform the backward deletion */
|
|
|
|
lcd_codec_action(priv, SLCDCODE_BACKDEL, 1);
|
|
|
|
lcd_get_curpos(priv, &row, &col);
|
|
}
|
|
else if (ch == ASCII_DEL)
|
|
{
|
|
/* Perform the forward deletion */
|
|
|
|
lcd_codec_action(priv, SLCDCODE_FWDDEL, 1);
|
|
|
|
lcd_get_curpos(priv, &row, &col);
|
|
}
|
|
else
|
|
{
|
|
/* All others are fair game. See if we need to wrap line. */
|
|
|
|
if (col >= priv->cfg.cols)
|
|
{
|
|
row += 1;
|
|
if (row >= priv->cfg.rows)
|
|
{
|
|
lcd_scroll_up(priv);
|
|
row = priv->cfg.rows - 1;
|
|
}
|
|
|
|
col = 0;
|
|
lcd_set_curpos(priv, row, col);
|
|
}
|
|
|
|
lcd_putdata(priv, ch);
|
|
++col;
|
|
}
|
|
}
|
|
else /* (result == SLCDRET_SPEC) */ /* A special SLCD action was returned */
|
|
{
|
|
lcd_codec_action(priv, (enum slcdcode_e)ch, count);
|
|
|
|
/* we can't know what happened, so it's easier just to re-inquire
|
|
* as to where we are.
|
|
*/
|
|
|
|
lcd_get_curpos(priv, &row, &col);
|
|
}
|
|
}
|
|
|
|
/* Wherever we wound up, update our logical file pos to reflect it */
|
|
|
|
lcd_curpos_to_fpos(priv, row, col, &filep->f_pos);
|
|
|
|
nxsem_post(&priv->sem_excl);
|
|
return buflen;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: pcf8574_lcd_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 pcf8574_lcd_seek(FAR struct file *filep, off_t offset, int whence)
|
|
{
|
|
FAR struct inode *inode = filep->f_inode;
|
|
FAR struct pcf8574_lcd_dev_s *priv = (FAR struct pcf8574_lcd_dev_s *)inode->i_private;
|
|
int maxpos;
|
|
|
|
nxsem_wait(&priv->sem_excl);
|
|
|
|
maxpos = priv->cfg.rows * priv->cfg.cols + (priv->cfg.rows - 1);
|
|
switch (whence)
|
|
{
|
|
case SEEK_CUR:
|
|
filep->f_pos += offset;
|
|
if (filep->f_pos > maxpos)
|
|
filep->f_pos = maxpos;
|
|
break;
|
|
|
|
case SEEK_SET:
|
|
filep->f_pos = offset;
|
|
if (filep->f_pos > maxpos)
|
|
filep->f_pos = maxpos;
|
|
break;
|
|
|
|
case SEEK_END:
|
|
filep->f_pos = maxpos;
|
|
break;
|
|
|
|
default:
|
|
/* Return EINVAL if the whence argument is invalid */
|
|
filep->f_pos = -EINVAL;
|
|
}
|
|
|
|
nxsem_post(&priv->sem_excl);
|
|
return filep->f_pos;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: pcf8574_lcd_ioctl
|
|
*
|
|
* Description:
|
|
* Perform device operations that are outside the standard I/O model.
|
|
*
|
|
****************************************************************************/
|
|
|
|
static int pcf8574_lcd_ioctl(FAR struct file *filep, int cmd,
|
|
unsigned long arg)
|
|
{
|
|
switch (cmd)
|
|
{
|
|
case SLCDIOC_GETATTRIBUTES: /* SLCDIOC_GETATTRIBUTES: Get the attributes of the SLCD */
|
|
{
|
|
FAR struct inode *inode = filep->f_inode;
|
|
FAR struct pcf8574_lcd_dev_s *priv = (FAR struct pcf8574_lcd_dev_s *)inode->i_private;
|
|
FAR struct slcd_attributes_s *attr = (FAR struct slcd_attributes_s *)((uintptr_t)arg);
|
|
|
|
lcdinfo("SLCDIOC_GETATTRIBUTES:\n");
|
|
|
|
if (!attr)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
attr->nrows = priv->cfg.rows;
|
|
attr->ncolumns = priv->cfg.cols;
|
|
attr->nbars = 0;
|
|
attr->maxcontrast = 0;
|
|
attr->maxbrightness = 1; /* 'brightness' for us is the backlight */
|
|
}
|
|
break;
|
|
|
|
case SLCDIOC_CURPOS: /* SLCDIOC_CURPOS: Get the SLCD cursor position */
|
|
{
|
|
FAR struct inode *inode = filep->f_inode;
|
|
FAR struct pcf8574_lcd_dev_s *priv = (FAR struct pcf8574_lcd_dev_s *)inode->i_private;
|
|
FAR struct slcd_curpos_s *attr = (FAR struct slcd_curpos_s *)((uintptr_t)arg);
|
|
uint8_t row;
|
|
uint8_t col;
|
|
|
|
nxsem_wait(&priv->sem_excl);
|
|
|
|
lcd_get_curpos(priv, &row, &col);
|
|
attr->row = row;
|
|
attr->column = col;
|
|
|
|
nxsem_post(&priv->sem_excl);
|
|
}
|
|
break;
|
|
|
|
case SLCDIOC_GETBRIGHTNESS: /* Get the current brightness setting */
|
|
{
|
|
FAR struct inode *inode = filep->f_inode;
|
|
FAR struct pcf8574_lcd_dev_s *priv = (FAR struct pcf8574_lcd_dev_s *)inode->i_private;
|
|
bool bOn;
|
|
|
|
bOn = (priv->bl_bit && priv->cfg.bl_active_high) || (!priv->bl_bit && !priv->cfg.bl_active_high);
|
|
*(int*)((uintptr_t)arg) = bOn ? 1 : 0;
|
|
}
|
|
break;
|
|
|
|
case SLCDIOC_SETBRIGHTNESS: /* Set the brightness to a new value */
|
|
{
|
|
FAR struct inode *inode = filep->f_inode;
|
|
FAR struct pcf8574_lcd_dev_s *priv = (FAR struct pcf8574_lcd_dev_s *)inode->i_private;
|
|
|
|
nxsem_wait(&priv->sem_excl);
|
|
lcd_backlight(priv, arg ? true : false);
|
|
nxsem_post(&priv->sem_excl);
|
|
}
|
|
break;
|
|
|
|
case SLCDIOC_CREATECHAR: /* Create a custom character pattern */
|
|
{
|
|
FAR struct inode *inode = filep->f_inode;
|
|
FAR struct pcf8574_lcd_dev_s *priv = (FAR struct pcf8574_lcd_dev_s *)inode->i_private;
|
|
FAR struct slcd_createchar_s *attr = (FAR struct slcd_createchar_s *)((uintptr_t)arg);
|
|
|
|
nxsem_wait(&priv->sem_excl);
|
|
lcd_create_char(priv, attr->idx, attr->bmp);
|
|
nxsem_post(&priv->sem_excl);
|
|
}
|
|
break;
|
|
|
|
case SLCDIOC_SETBAR: /* SLCDIOC_SETBAR: Set bars on a bar display */
|
|
case SLCDIOC_GETCONTRAST: /* SLCDIOC_GETCONTRAST: Get the current contrast setting */
|
|
case SLCDIOC_SETCONTRAST: /* SLCDIOC_SETCONTRAST: Set the contrast to a new value */
|
|
default:
|
|
return -ENOTTY;
|
|
}
|
|
|
|
return OK;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: pcf8574lcd_poll
|
|
****************************************************************************/
|
|
|
|
#ifndef CONFIG_DISABLE_POLL
|
|
static int pcf8574lcd_poll(FAR struct file *filep, FAR struct pollfd *fds,
|
|
bool setup)
|
|
{
|
|
if (setup)
|
|
{
|
|
/* Data is always available to be read */
|
|
|
|
fds->revents |= (fds->events & (POLLIN|POLLOUT));
|
|
if (fds->revents != 0)
|
|
{
|
|
nxsem_post(fds->sem);
|
|
}
|
|
}
|
|
|
|
return OK;
|
|
}
|
|
#endif
|
|
|
|
/****************************************************************************
|
|
* Name: pcf8574_lcd_unlink
|
|
****************************************************************************/
|
|
|
|
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
|
|
static int pcf8574_lcd_unlink(FAR struct inode *inode)
|
|
{
|
|
FAR struct pcf8574_lcd_dev_s *priv = (FAR struct pcf8574_lcd_dev_s *)inode->i_private;
|
|
int ret = OK;
|
|
|
|
nxsem_wait(&priv->sem_excl);
|
|
|
|
priv->unlinked = true;
|
|
|
|
/* If there are no open references to the driver then tear it down now */
|
|
if (priv->refs == 0)
|
|
{
|
|
/* We have no real teardown at present */
|
|
ret = OK;
|
|
}
|
|
|
|
nxsem_post(&priv->sem_excl);
|
|
return ret;
|
|
}
|
|
#endif
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: pcf8574_lcd_backpack_register
|
|
*
|
|
* Description:
|
|
* Register a character driver that is an I2C LCD 'backpack' for the
|
|
* ever-popular HD44780 based 16x2 LCD via pcf8574 I2C IO expander.
|
|
*
|
|
****************************************************************************/
|
|
|
|
int pcf8574_lcd_backpack_register(FAR const char *devpath,
|
|
FAR struct i2c_master_s *i2c,
|
|
FAR struct pcf8574_lcd_backpack_config_s *cfg)
|
|
{
|
|
FAR struct pcf8574_lcd_dev_s *priv;
|
|
int ret;
|
|
|
|
/* Sanity check on geometry */
|
|
|
|
if (cfg->rows < 1 || cfg->rows > 4)
|
|
{
|
|
lcdinfo("Display rows must be 1-4\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if ((cfg->cols < 1 || cfg->cols > 64) || (cfg->rows == 4 && cfg->cols > 32))
|
|
{
|
|
lcdinfo("Display cols must be 1-64, and may not be part of a 4x40 configuration\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Initialize the device structure */
|
|
|
|
priv = (FAR struct pcf8574_lcd_dev_s *)kmm_malloc(sizeof(struct pcf8574_lcd_dev_s));
|
|
if (!priv)
|
|
{
|
|
lcdinfo("Failed to allocate instance\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
priv->i2c = i2c;
|
|
priv->cfg = *cfg;
|
|
priv->bl_bit = priv->cfg.bl_active_high ? 0 : (1 << priv->cfg.bl);
|
|
priv->refs = 0;
|
|
priv->unlinked = false;
|
|
nxsem_init(&priv->sem_excl, 0, 1);
|
|
|
|
/* Initialize */
|
|
|
|
lcd_init(priv);
|
|
|
|
/* Register the character driver */
|
|
|
|
ret = register_driver(devpath, &g_pcf8574_lcd_fops, 0666, priv);
|
|
if (ret < 0)
|
|
{
|
|
lcdinfo("Failed to register driver: %d\n", ret);
|
|
kmm_free(priv);
|
|
}
|
|
|
|
lcdinfo("pcf8574_lcd_backpack driver loaded successfully!\n");
|
|
return ret;
|
|
}
|