nuttx/configs/stm32f4discovery/src/stm32_xen1210.c
2017-02-27 14:21:30 -06:00

357 lines
11 KiB
C

/************************************************************************************
* configs/stm32f4discovery/src/stm32_xen1210.c
*
* Copyright (C) 2016 Gregory Nutt. All rights reserved.
* Author: Alan Carvalho de Assis <acassis@gmail.com>
*
* 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 <stdbool.h>
#include <stdio.h>
#include <debug.h>
#include <errno.h>
#include <nuttx/spi/spi.h>
#include <nuttx/sensors/xen1210.h>
#include <nuttx/drivers/pwm.h>
#include <arch/board/board.h>
#include <nuttx/irq.h>
#include <nuttx/arch.h>
#include <nuttx/fs/ioctl.h>
#include "stm32_gpio.h"
#include "stm32_spi.h"
#include "stm32_pwm.h"
#include "stm32f4discovery.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
#ifdef CONFIG_XEN1210
#ifndef CONFIG_STM32_SPI1
# error "XEN1210 support requires CONFIG_STM32_SPI1"
#endif
#define CONFIG_XEN1210_SPIDEV 1
#ifndef CONFIG_XEN1210_DEVMINOR
# define CONFIG_XEN1210_DEVMINOR 0
#endif
#ifndef CONFIG_STM32_TIM1
# error "XEN1210 needs PWM on TIM1 CH1 to be its clock!"
#endif
#ifndef CONFIG_STM32_TIM1_PWM
# error "XEN1210 needs PWM on TIM1 CH1 to be its clock!"
#endif
#if CONFIG_STM32_TIM1_CHANNEL != XEN1210_PWMCHANNEL
# error "XEN1210 needs PWM on TIM1 CH1 to be its clock!"
#endif
/****************************************************************************
* Private Types
****************************************************************************/
struct stm32_xen1210config_s
{
/* Configuration structure as seen by the XEN1210 driver */
struct xen1210_config_s config;
/* Additional private definitions only known to this driver */
XEN1210_HANDLE handle; /* The XEN1210 driver handle */
xen1210_handler_t handler; /* The XEN1210 interrupt handler */
FAR void *arg; /* Argument to pass to the interrupt handler */
};
/****************************************************************************
* Static Function Prototypes
****************************************************************************/
/* IRQ/GPIO access callbacks. These operations all hidden behind callbacks
* to isolate the XEN1210 driver from differences in GPIO interrupt handling
* by varying boards and MCUs.
*
* attach - Attach the XEN1210 interrupt handler to the GPIO interrupt
* enable - Enable or disable the GPIO interrupt
* clear - Acknowledge/clear any pending GPIO interrupt
*/
static int xen1210_attach(FAR struct xen1210_config_s *state,
xen1210_handler_t handler, FAR void *arg);
static void xen1210_enable(FAR struct xen1210_config_s *state, bool enable);
static void xen1210_clear(FAR struct xen1210_config_s *state);
/****************************************************************************
* Private Data
****************************************************************************/
/* A reference to a structure of this type must be passed to the XEN1210
* driver. This structure provides information about the configuration
* of the XEN1210 and provides some board-specific hooks.
*
* Memory for this structure is provided by the caller. It is not copied
* by the driver and is presumed to persist while the driver is active. The
* memory must be writable because, under certain circumstances, the driver
* may modify frequency or X plate resistance values.
*/
static struct stm32_xen1210config_s g_xen1210config =
{
.config =
{
.frequency = XEN1210_SPI_MAXFREQUENCY,
.attach = xen1210_attach,
.enable = xen1210_enable,
.clear = xen1210_clear,
},
};
/****************************************************************************
* Private Functions
****************************************************************************/
/* This is the XEN1210 Interrupt handler */
int xen1210_interrupt(int irq, FAR void *context, FAR void *arg)
{
/* Verify that we have a handler attached */
if (g_xen1210config.handler)
{
/* Yes.. forward with interrupt along with its argument */
g_xen1210config.handler(&g_xen1210config.config, g_xen1210config.arg);
}
return OK;
}
/* IRQ/GPIO access callbacks. These operations all hidden behind
* callbacks to isolate the XEN1210 driver from differences in GPIO
* interrupt handling by varying boards and MCUs.
*
* attach - Attach the XEN1210 interrupt handler to the GPIO interrupt
* enable - Enable or disable the GPIO interrupt
* clear - Acknowledge/clear any pending GPIO interrupt
*/
static int xen1210_attach(FAR struct xen1210_config_s *state,
xen1210_handler_t handler, FAR void *arg)
{
FAR struct stm32_xen1210config_s *priv =
(FAR struct stm32_xen1210config_s *)state;
sninfo("Saving handler %p\n", handler);
DEBUGASSERT(priv);
/* Just save the handler and its argument. We will use it when interrupts
* are enabled
*/
priv->handler = handler;
priv->arg = arg;
return OK;
}
static void xen1210_enable(FAR struct xen1210_config_s *state, bool enable)
{
irqstate_t flags;
/* Attach and enable, or detach and disable. Enabling and disabling GPIO
* interrupts is a multi-step process so the safest thing is to keep
* interrupts disabled during the reconfiguration.
*/
flags = enter_critical_section();
if (enable)
{
/* Configure the interrupt using the SAVED handler */
stm32_configgpio(GPIO_XEN1210_INT);
(void)stm32_gpiosetevent(GPIO_XEN1210_INT, false, true,
true, xen1210_interrupt, NULL);
}
else
{
/* Configure the interrupt with a NULL handler to disable it */
(void)stm32_gpiosetevent(GPIO_XEN1210_INT, false, false, false,
NULL, NULL);
}
leave_critical_section(flags);
}
static void xen1210_clear(FAR struct xen1210_config_s *state)
{
/* Does nothing */
}
/****************************************************************************
* Public Functions
****************************************************************************/
/************************************************************************************
* Name: xen1210_pwm_setup
*
* Description:
* All STM32 architectures must provide the following interface to work with
* examples/pwm.
*
************************************************************************************/
int xen1210_pwm_setup(void)
{
static bool initialized = false;
struct pwm_lowerhalf_s *pwm;
struct pwm_info_s info;
/* Have we already initialized? */
if (!initialized)
{
/* Call stm32_pwminitialize() to get an instance of the PWM interface */
pwm = stm32_pwminitialize(XEN1210_PWMTIMER);
if (!pwm)
{
_err("ERROR: Failed to get the STM32 PWM lower half\n");
return -ENODEV;
}
/* Define frequency and duty cycle: 2MHz @ 50% */
info.frequency = 2000000; /* 2MHz */
info.duty = 32768; /* This value means 50% */
/* Initialize PWM */
pwm->ops->setup(pwm);
pwm->ops->start(pwm, &info);
/* Now we are initialized */
initialized = true;
}
return 0;
}
/****************************************************************************
* Name: xen1210_archinitialize
*
* Description:
* Each board that supports an xen1210 device must provide this function.
* This function is called by application-specific, setup logic to
* configure the accelerometer device. This function will register the
* driver as /dev/accelN where N is the minor device number.
*
* Input Parameters:
* 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_archinitialize(int minor)
{
FAR struct spi_dev_s *dev;
int ret;
sninfo("minor %d\n", minor);
DEBUGASSERT(minor == 0);
/* Check if we are already initialized */
if (!g_xen1210config.handle)
{
sninfo("Initializing\n");
/* XEN1210 needs an external clock 1-4MHz
* We are using PWM on TIM1 CH1 to do it!
*/
(void)xen1210_pwm_setup();
/* Configure the XEN1210 interrupt pin as an input */
(void)stm32_configgpio(GPIO_XEN1210_INT);
/* Get an instance of the I2C interface */
dev = stm32_spibus_initialize(CONFIG_XEN1210_SPIDEV);
if (!dev)
{
snerr("ERROR: Failed to initialize SPI bus %d\n", CONFIG_XEN1210_SPIDEV);
return -ENODEV;
}
/* Instantiate the XEN1210 driver */
g_xen1210config.handle =
xen1210_instantiate(dev, (FAR struct xen1210_config_s *)&g_xen1210config);
if (!g_xen1210config.handle)
{
snerr("ERROR: Failed to instantiate the XEN1210 driver\n");
return -ENODEV;
}
/* Initialize and register the XEN1210 driver */
ret = xen1210_register(g_xen1210config.handle, CONFIG_XEN1210_DEVMINOR);
if (ret < 0)
{
snerr("ERROR: Failed to register XEN1210 driver: %d\n", ret);
return ret;
}
}
return OK;
}
#endif /* CONFIG_SENSORS_XEN1210 */