incubator-nuttx/drivers/sensors/xen1210.c

444 lines
12 KiB
C

/****************************************************************************
* drivers/sensors/xen1210.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.
*
****************************************************************************/
/* This driver is used to interface with Sensixs XEN1210 3D-board. */
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <unistd.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <inttypes.h>
#include <stdio.h>
#include <nuttx/kmalloc.h>
#include <nuttx/spi/spi.h>
#include <nuttx/sensors/xen1210.h>
#include <nuttx/random.h>
#include "xen1210.h"
#if defined(CONFIG_SENSORS_XEN1210)
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/* Character driver methods */
static ssize_t xen1210_read(FAR struct file *filep, FAR char *buffer,
size_t len);
/****************************************************************************
* Private Data
****************************************************************************/
/* This the vtable that supports the character driver interface */
static const struct file_operations g_xen1210fops =
{
NULL, /* open */
NULL, /* close */
xen1210_read, /* read */
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: xen1210_configspi
*
* Description:
*
****************************************************************************/
static inline void xen1210_configspi(FAR struct spi_dev_s *spi)
{
/* Configure SPI for the XEN1210 */
SPI_SETMODE(spi, SPIDEV_MODE1);
SPI_SETBITS(spi, 8);
SPI_HWFEATURES(spi, 0);
SPI_SETFREQUENCY(spi, XEN1210_SPI_MAXFREQUENCY);
}
/****************************************************************************
* Name: xen1210_read
*
* Description:
* Standard character driver read method.
*
****************************************************************************/
static ssize_t xen1210_read(FAR struct file *filep, FAR char *buffer,
size_t len)
{
FAR struct inode *inode;
FAR struct xen1210_dev_s *priv;
int ret;
sninfo("len=%d\n", len);
inode = filep->f_inode;
DEBUGASSERT(inode->i_private);
priv = inode->i_private;
/* Verify that the caller has provided a buffer large enough to receive
* the magnetometer data.
*/
if (len < sizeof(struct xen1210_sample_s))
{
/* We could provide logic to break up a touch report into segments and
* handle smaller reads... but why?
*/
snerr("Failed: Trying to read less bytes than sensor sample!\n");
return -ENOSYS;
}
/* Get exclusive access to the driver data structure */
ret = nxmutex_lock(&priv->lock);
if (ret < 0)
{
/* This should only happen if the wait was canceled by an signal */
snerr("Failed: Cannot get exclusive access to driver structure!\n");
return ret;
}
sninfo("X = 0x%06" PRIX32 "\n", priv->sample.data_x);
sninfo("Y = 0x%06" PRIX32 "\n", priv->sample.data_y);
sninfo("Z = 0x%06" PRIX32 "\n", priv->sample.data_z);
/* Return read sample */
buffer = (FAR char *) &priv->sample;
nxmutex_unlock(&priv->lock);
return sizeof(struct xen1210_sample_s);
}
/****************************************************************************
* Name: xen1210_worker
*
* Description:
* This is the "bottom half" of the XEN1210 interrupt handler
*
****************************************************************************/
static void xen1210_worker(FAR void *arg)
{
FAR struct xen1210_dev_s *priv = (FAR struct xen1210_dev_s *)arg;
DEBUGASSERT(priv && priv->config);
/* Read the sensors */
xen1210_getdata(priv);
/* Re-enable the XEN1210 GPIO interrupt */
priv->config->enable(priv->config, true);
}
/****************************************************************************
* Name: xen1210_interrupt
*
* Description:
* The XEN1210 interrupt handler
*
****************************************************************************/
static void xen1210_interrupt(FAR struct xen1210_config_s *config,
FAR void *arg)
{
FAR struct xen1210_dev_s *priv = (FAR struct xen1210_dev_s *)arg;
int ret;
DEBUGASSERT(priv && priv->config == config);
/* Disable further interrupts */
config->enable(config, false);
/* Check if interrupt work is already queue. If it is already busy, then
* we already have interrupt processing in the pipeline and we need to do
* nothing more.
*/
if (work_available(&priv->work))
{
/* Yes.. Transfer processing to the worker thread. Since XEN1210
* interrupts are disabled while the work is pending, no special
* action should be required to protect the work queue.
*/
ret = work_queue(HPWORK, &priv->work, xen1210_worker, priv, 0);
if (ret != 0)
{
snerr("ERROR: Failed to queue work: %d\n", ret);
}
}
/* Clear any pending interrupts and return success */
config->clear(config);
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: xen1210_instantiate
*
* Description:
* Instantiate and configure the XEN1210 device driver to use the provided
* SPI device instance.
*
* Input Parameters:
* dev - An I2C or SPI driver instance
* config - Persistent board configuration data
*
* Returned Value:
* A non-zero handle is returned on success. This handle may then be used
* to configure the XEN1210 driver as necessary. A NULL handle value is
* returned on failure.
*
****************************************************************************/
XEN1210_HANDLE xen1210_instantiate(FAR struct spi_dev_s *dev,
FAR struct xen1210_config_s *config)
{
FAR struct xen1210_dev_s *priv;
uint32_t regval;
/* Allocate the XEN1210 driver instance */
priv = (FAR struct xen1210_dev_s *)
kmm_zalloc(sizeof(struct xen1210_dev_s));
if (!priv)
{
snerr("ERROR: Failed to allocate the device structure!\n");
return NULL;
}
/* Initialize the device state structure */
nxmutex_init(&priv->lock);
priv->config = config;
priv->spi = dev;
/* Attach the XEN1210 interrupt handler. */
config->attach(config, (xen1210_handler_t)xen1210_interrupt,
(FAR void *)priv);
/* Device initialization sequence */
/* Power off */
regval = (XEN1210_POWEROFF);
xen1210_putdata(priv, regval);
/* Timing */
regval = (XEN1210_TIMING);
regval |= 0x131100;
xen1210_putdata(priv, regval);
/* Test */
regval = (XEN1210_TEST);
regval |= 0x003a00;
xen1210_putdata(priv, regval);
/* Power on */
regval = (XEN1210_POWERON);
xen1210_putdata(priv, regval); /* X axis */
config->clear(config);
config->enable(config, true);
/* Return our private data structure as an opaque handle */
return (XEN1210_HANDLE)priv;
}
/****************************************************************************
* Name: xen1210_register
*
* Description:
* This function will register the touchscreen driver as /dev/accelN where N
* is the minor device number
*
* Input Parameters:
* handle - The handle previously returned by xen1210_register
* minor - The input device minor number
*
* Returned Value:
* Zero is returned on success. Otherwise, a negated errno value is
* returned to indicate the nature of the failure.
*
****************************************************************************/
int xen1210_register(XEN1210_HANDLE handle, int minor)
{
FAR struct xen1210_dev_s *priv = (FAR struct xen1210_dev_s *)handle;
char devname[DEV_NAMELEN];
int ret;
sninfo("handle=%p minor=%d\n", handle, minor);
DEBUGASSERT(priv);
/* Get exclusive access to the device structure */
ret = nxmutex_lock(&priv->lock);
if (ret < 0)
{
snerr("ERROR: nxsem_wait failed: %d\n", ret);
return ret;
}
/* Register the character driver */
snprintf(devname, sizeof(devname), DEV_FORMAT, minor);
ret = register_driver(devname, &g_xen1210fops, 0444, priv);
if (ret < 0)
{
snerr("ERROR: Failed to register driver %s: %d\n", devname, ret);
nxmutex_unlock(&priv->lock);
return ret;
}
/* Indicate that the accelerometer was successfully initialized */
priv->status |= XEN1210_STAT_INITIALIZED; /* Accelerometer is initialized */
nxmutex_unlock(&priv->lock);
return ret;
}
/****************************************************************************
* Name: xen1210_getdata
*
* Description:
* Read 24-bit from XEN1210 buffer, read three times (3 sensors)
*
****************************************************************************/
void xen1210_getdata(FAR struct xen1210_dev_s *priv)
{
uint32_t regval;
/* If SPI bus is shared then lock and configure it */
SPI_LOCK(priv->spi, true);
xen1210_configspi(priv->spi);
/* Select the XEN1210 */
SPI_SELECT(priv->spi, SPIDEV_ACCELEROMETER(0), true);
/* Read three times 3 bytes = 24 bits * 3 */
SPI_RECVBLOCK(priv->spi, &regval, 3);
priv->sample.data_x = regval & 0xffffff;
SPI_RECVBLOCK(priv->spi, &regval, 3);
priv->sample.data_y = regval & 0xffffff;
SPI_RECVBLOCK(priv->spi, &regval, 3);
priv->sample.data_z = regval & 0xffffff;
/* Deselect the XEN1210 */
SPI_SELECT(priv->spi, SPIDEV_ACCELEROMETER(0), false);
/* Unlock bus */
SPI_LOCK(priv->spi, false);
#ifdef CONFIG_XEN1210_REGDEBUG
_err("%02x->%02x\n", regaddr, regval);
#endif
/* Feed sensor data to entropy pool */
add_sensor_randomness((priv->sample.data_x << 8) ^
(priv->sample.data_y << 4) ^
(priv->sample.data_z << 4));
}
/****************************************************************************
* Name: xen1210_putdata
*
* Description:
* Write 24-bit to XEN1210 buffer, write three times (3 sensors)
*
****************************************************************************/
void xen1210_putdata(FAR struct xen1210_dev_s *priv, uint32_t regval)
{
#ifdef CONFIG_XEN1210_REGDEBUG
_err("%02x<-%02x\n", regaddr, regval);
#endif
/* If SPI bus is shared then lock and configure it */
SPI_LOCK(priv->spi, true);
xen1210_configspi(priv->spi);
/* Select the XEN1210 */
SPI_SELECT(priv->spi, SPIDEV_ACCELEROMETER(0), true);
/* We need to write to 3 sensors in the daisy-chain */
/* Write three times 3 bytes */
SPI_SNDBLOCK(priv->spi, &regval, 3);
SPI_SNDBLOCK(priv->spi, &regval, 3);
SPI_SNDBLOCK(priv->spi, &regval, 3);
/* Deselect the XEN1210 */
SPI_SELECT(priv->spi, SPIDEV_ACCELEROMETER(0), false);
/* Unlock bus */
SPI_LOCK(priv->spi, false);
}
#endif /* CONFIG_SENSORS_XEN1210 */