summaryrefslogtreecommitdiff
path: root/nuttx/drivers/analog/adc.c
diff options
context:
space:
mode:
Diffstat (limited to 'nuttx/drivers/analog/adc.c')
-rw-r--r--nuttx/drivers/analog/adc.c405
1 files changed, 405 insertions, 0 deletions
diff --git a/nuttx/drivers/analog/adc.c b/nuttx/drivers/analog/adc.c
new file mode 100644
index 000000000..5505a282d
--- /dev/null
+++ b/nuttx/drivers/analog/adc.c
@@ -0,0 +1,405 @@
+/****************************************************************************
+ * drivers/adc/adc.c
+ *
+ * Copyright (C) 2011 Li Zhuoyi. All rights reserved.
+ * Author: Li Zhuoyi <lzyy.cn@gmail.com>
+ * History: 0.1 2011-08-04 initial version
+ *
+ * Derived from drivers/can.c
+ *
+ * Copyright (C) 2008-2009 Gregory Nutt. All rights reserved.
+ * Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ * used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <unistd.h>
+#include <string.h>
+#include <semaphore.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/fs.h>
+#include <nuttx/arch.h>
+#include <nuttx/analog/adc.h>
+
+#include <arch/irq.h>
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static int adc_open(FAR struct file *filep);
+static int adc_close(FAR struct file *filep);
+static ssize_t adc_read(FAR struct file *, FAR char *, size_t);
+static ssize_t adc_write(FAR struct file *filep, FAR const char *buffer, size_t buflen);
+static int adc_ioctl(FAR struct file *filep,int cmd,unsigned long arg);
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+static const struct file_operations adc_fops =
+{
+ adc_open, /* open */
+ adc_close, /* close */
+ adc_read, /* read */
+ adc_write, /* write */
+ 0, /* seek */
+ adc_ioctl /* ioctl */
+#ifndef CONFIG_DISABLE_POLL
+ , 0 /* poll */
+#endif
+};
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+/************************************************************************************
+ * Name: adc_open
+ *
+ * Description:
+ * This function is called whenever the ADC device is opened.
+ *
+ ************************************************************************************/
+
+static int adc_open(FAR struct file *filep)
+{
+ FAR struct inode *inode = filep->f_inode;
+ FAR struct adc_dev_s *dev = inode->i_private;
+ uint8_t tmp;
+ int ret = OK;
+
+ /* If the port is the middle of closing, wait until the close is finished */
+
+ if (sem_wait(&dev->cd_closesem) != OK)
+ {
+ ret = -errno;
+ }
+ else
+ {
+ /* Increment the count of references to the device. If this the first
+ * time that the driver has been opened for this device, then initialize
+ * the device.
+ */
+
+ tmp = dev->cd_ocount + 1;
+ if (tmp == 0)
+ {
+ /* More than 255 opens; uint8_t overflows to zero */
+
+ ret = -EMFILE;
+ }
+ else
+ {
+ /* Check if this is the first time that the driver has been opened. */
+
+ if (tmp == 1)
+ {
+ /* Yes.. perform one time hardware initialization. */
+
+ irqstate_t flags = irqsave();
+ ret = dev->cd_ops->ao_setup(dev);
+ if (ret == OK)
+ {
+ /* Mark the FIFOs empty */
+
+ dev->cd_recv.af_head = 0;
+ dev->cd_recv.af_tail = 0;
+
+ /* Finally, Enable the CAN RX interrupt */
+
+ dev->cd_ops->ao_rxint(dev, true);
+
+ /* Save the new open count on success */
+
+ dev->cd_ocount = tmp;
+ }
+ irqrestore(flags);
+ }
+ }
+ sem_post(&dev->cd_closesem);
+ }
+ return ret;
+}
+
+/************************************************************************************
+ * Name: adc_close
+ *
+ * Description:
+ * This routine is called when the ADC device is closed.
+ * It waits for the last remaining data to be sent.
+ *
+ ************************************************************************************/
+
+static int adc_close(FAR struct file *filep)
+{
+ FAR struct inode *inode = filep->f_inode;
+ FAR struct adc_dev_s *dev = inode->i_private;
+ irqstate_t flags;
+ int ret = OK;
+
+ if (sem_wait(&dev->cd_closesem) != OK)
+ {
+ ret = -errno;
+ }
+ else
+ {
+ /* Decrement the references to the driver. If the reference count will
+ * decrement to 0, then uninitialize the driver.
+ */
+
+ if (dev->cd_ocount > 1)
+ {
+ dev->cd_ocount--;
+ sem_post(&dev->cd_closesem);
+ }
+ else
+ {
+ /* There are no more references to the port */
+
+ dev->cd_ocount = 0;
+
+
+ /* Free the IRQ and disable the ADC device */
+
+ flags = irqsave(); /* Disable interrupts */
+ dev->cd_ops->ao_shutdown(dev); /* Disable the ADC */
+ irqrestore(flags);
+
+ sem_post(&dev->cd_closesem);
+ }
+ }
+ return ret;
+}
+
+/****************************************************************************
+ * Name: adc_read
+ ****************************************************************************/
+
+static ssize_t adc_read(FAR struct file *filep, FAR char *buffer, size_t buflen)
+{
+ FAR struct inode *inode = filep->f_inode;
+ FAR struct adc_dev_s *dev = inode->i_private;
+ size_t nread;
+ irqstate_t flags;
+ int ret = 0;
+ int msglen;
+
+ if (buflen % 5 ==0 )
+ msglen=5;
+ else if (buflen % 4 ==0 )
+ msglen=4;
+ else if (buflen % 3 ==0 )
+ msglen=3;
+ else if (buflen % 2 ==0 )
+ msglen=2;
+ else if (buflen == 1)
+ msglen=1;
+ else
+ msglen=5;
+
+ if (buflen >= msglen)
+ {
+ /* Interrupts must be disabled while accessing the cd_recv FIFO */
+
+ flags = irqsave();
+ while (dev->cd_recv.af_head == dev->cd_recv.af_tail)
+ {
+ /* The receive FIFO is empty -- was non-blocking mode selected? */
+
+ if (filep->f_oflags & O_NONBLOCK)
+ {
+ ret = -EAGAIN;
+ goto return_with_irqdisabled;
+ }
+
+ /* Wait for a message to be received */
+
+ dev->cd_nrxwaiters++;
+ ret = sem_wait(&dev->cd_recv.af_sem);
+ dev->cd_nrxwaiters--;
+ if (ret < 0)
+ {
+ ret = -errno;
+ goto return_with_irqdisabled;
+ }
+ }
+
+ /* The cd_recv FIFO is not empty. Copy all buffered data that will fit
+ * in the user buffer.
+ */
+
+ nread = 0;
+ do
+ {
+ FAR struct adc_msg_s *msg = &dev->cd_recv.af_buffer[dev->cd_recv.af_head];
+
+ /* Will the next message in the FIFO fit into the user buffer? */
+
+ if (ret + msglen > buflen)
+ {
+ break;
+ }
+
+ /* Copy the message to the user buffer */
+
+ if (msglen==1)
+ {
+ buffer[nread]=msg->am_data>>24; //Only one channel,read highest 8bits
+ }
+ else if (msglen==2)
+ {
+ *(int16_t *)&buffer[nread]=msg->am_data>>16; //Only one channel,read highest 16bits
+ }
+ else if (msglen==3)
+ {
+ buffer[nread]=msg->am_channel;
+ *(int16_t *)&buffer[nread+1]=msg->am_data>>16; //read channel highest 16bits
+ }
+ else if (msglen==4)
+ {
+ *(int32_t *)&buffer[nread]=msg->am_data; //read channel highest 24bits
+ buffer[nread]=msg->am_channel;
+ }
+ else
+ {
+ *(int32_t *)&buffer[nread+1]=msg->am_data; //read all
+ buffer[nread]=msg->am_channel;
+ }
+ nread += msglen;
+
+ /* Increment the head of the circular message buffer */
+
+ if (++dev->cd_recv.af_head >= CONFIG_ADC_FIFOSIZE)
+ {
+ dev->cd_recv.af_head = 0;
+ }
+ }
+ while (dev->cd_recv.af_head != dev->cd_recv.af_tail);
+
+ /* All on the messages have bee transferred. Return the number of bytes
+ * that were read.
+ */
+
+ ret = nread;
+
+return_with_irqdisabled:
+ irqrestore(flags);
+ }
+ return ret;
+}
+
+/************************************************************************************
+ * Name: adc_write
+ ************************************************************************************/
+
+static ssize_t adc_write(FAR struct file *filep, FAR const char *buffer, size_t buflen)
+{
+ return 0;
+}
+
+/************************************************************************************
+ * Name: adc_ioctl
+ ************************************************************************************/
+
+static int adc_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
+{
+ FAR struct inode *inode = filep->f_inode;
+ FAR struct adc_dev_s *dev = inode->i_private;
+ int ret = OK;
+
+ ret = dev->cd_ops->ao_ioctl(dev, cmd, arg);
+ return ret;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+int adc_receive(FAR struct adc_dev_s *dev, uint8_t ch, int32_t data)
+{
+ FAR struct adc_fifo_s *fifo = &dev->cd_recv;
+ int nexttail;
+ int err = -ENOMEM;
+
+ /* Check if adding this new message would over-run the drivers ability to enqueue
+ * read data.
+ */
+
+ nexttail = fifo->af_tail + 1;
+ if (nexttail >= CONFIG_ADC_FIFOSIZE)
+ {
+ nexttail = 0;
+ }
+
+ /* Refuse the new data if the FIFO is full */
+
+ if (nexttail != fifo->af_head)
+ {
+ /* Add the new, decoded CAN message at the tail of the FIFO */
+
+ fifo->af_buffer[fifo->af_tail].am_channel = ch;
+ fifo->af_buffer[fifo->af_tail].am_data=data;
+
+ /* Increment the tail of the circular buffer */
+
+ fifo->af_tail = nexttail;
+
+ if( dev->cd_nrxwaiters>0)
+ sem_post(&fifo->af_sem);
+ err = OK;
+ }
+ return err;
+}
+
+int adc_register(FAR const char *path, FAR struct adc_dev_s *dev)
+{
+ /* Initialize the ADC device structure */
+
+ dev->cd_ocount = 0;
+
+ sem_init(&dev->cd_recv.af_sem, 0, 0);
+ sem_init(&dev->cd_closesem, 0, 1);
+
+ dev->cd_ops->ao_reset(dev);
+
+ return register_driver(path, &adc_fops, 0444, dev);
+}
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-28 13:13:19 +0000