can.c 4.07 KB
/****************************************************************************
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 *   Copyright (c) 2015, 2016 Airmind Development Team. All rights reserved.
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 *    distribution.
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 *    used to endorse or promote products derived from this software
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 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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 ****************************************************************************/

/**
 * @file mindpx_can.c
 *
 * Board-specific CAN functions.
 */

/************************************************************************************
 * Included Files
 ************************************************************************************/

#include <px4_platform_common/px4_config.h>

#include <errno.h>
#include <debug.h>

#include <nuttx/can/can.h>
#include <arch/board/board.h>

#include "chip.h"
#include "arm_arch.h"

#include "stm32.h"
#include "stm32_can.h"
#include "board_config.h"

#ifdef CONFIG_CAN

/************************************************************************************
 * Pre-processor Definitions
 ************************************************************************************/
/* Configuration ********************************************************************/

#if defined(CONFIG_STM32_CAN1) && defined(CONFIG_STM32_CAN2)
#  warning "Both CAN1 and CAN2 are enabled.  Assuming only CAN1."
#  undef CONFIG_STM32_CAN2
#endif

#ifdef CONFIG_STM32_CAN1
#  define CAN_PORT 1
#else
#  define CAN_PORT 2
#endif

/************************************************************************************
 * Private Functions
 ************************************************************************************/

/************************************************************************************
 * Public Functions
 ************************************************************************************/
int can_devinit(void);
/************************************************************************************
 * Name: can_devinit
 *
 * Description:
 *   All STM32 architectures must provide the following interface to work with
 *   examples/can.
 *
 ************************************************************************************/

int can_devinit(void)
{
	static bool initialized = false;
	struct can_dev_s *can;
	int ret;

	/* Check if we have already initialized */

	if (!initialized) {
		/* Call stm32_caninitialize() to get an instance of the CAN interface */

		can = stm32_caninitialize(CAN_PORT);

		if (can == NULL) {
			canerr("ERROR:  Failed to get CAN interface\n");
			return -ENODEV;
		}

		/* Register the CAN driver at "/dev/can0" */

		ret = can_register("/dev/can0", can);

		if (ret < 0) {
			canerr("ERROR: can_register failed: %d\n", ret);
			return ret;
		}

		/* Now we are initialized */

		initialized = true;
	}

	return OK;
}

#endif