io_timer driver:Only support capture if DIRECT_INPUT_TIMER_CHANNELS > 0

This removes the unused input capture capabilities from the px4io
   and saves 128 bytes of ram.

src/drivers/boards/common/board_common.h

@@ -185,6 +185,13 @@
 #  define BOARD_EEPROM_WP_CTRL(on_true)
 #endif
 
+/*
+ * Defined when a board has capture and uses channels.
+ */
+#if defined(DIRECT_INPUT_TIMER_CHANNELS) && DIRECT_INPUT_TIMER_CHANNELS > 0
+#define BOARD_HAS_CAPTURE 1
+#endif
+
 
 /************************************************************************************
  * Public Data

src/drivers/px4fmu/fmu.cpp

@@ -579,12 +579,15 @@ PX4FMU::set_mode(Mode mode)
 		_num_outputs = 1;
 		break;
 
+#if defined(BOARD_HAS_CAPTURE)
+
 	case MODE_2PWM2CAP:	// v1 multi-port with flow control lines as PWM
 		up_input_capture_set(2, Rising, 0, NULL, NULL);
 		up_input_capture_set(3, Rising, 0, NULL, NULL);
 		DEVICE_DEBUG("MODE_2PWM2CAP");
+		// no break
+#endif
 
-	// no break
 	case MODE_2PWM:	// v1 multi-port with flow control lines as PWM
 		DEVICE_DEBUG("MODE_2PWM");
 
@@ -598,11 +601,14 @@ PX4FMU::set_mode(Mode mode)
 
 		break;
 
+#if defined(BOARD_HAS_CAPTURE)
+
 	case MODE_3PWM1CAP:	// v1 multi-port with flow control lines as PWM
 		DEVICE_DEBUG("MODE_3PWM1CAP");
 		up_input_capture_set(3, Rising, 0, NULL, NULL);
+		// no break
+#endif
 
-	// no break
 	case MODE_3PWM:	// v1 multi-port with flow control lines as PWM
 		DEVICE_DEBUG("MODE_3PWM");
 
@@ -2701,6 +2707,8 @@ PX4FMU::capture_ioctl(struct file *filp, int cmd, unsigned long arg)
 {
 	int	ret = -EINVAL;
 
+#if defined(BOARD_HAS_CAPTURE)
+
 	lock();
 
 	input_capture_config_t *pconfig = 0;
@@ -2822,6 +2830,7 @@ PX4FMU::capture_ioctl(struct file *filp, int cmd, unsigned long arg)
 	}
 
 	unlock();
+#endif
 	return ret;
 }
 

src/drivers/stm32/drv_input_capture.c

@@ -79,6 +79,10 @@
 #include <stm32_gpio.h>
 #include <stm32_tim.h>
 
+#if defined(BOARD_HAS_CAPTURE)
+
+/* Support Input capture  */
+
 #define _REG32(_base, _reg)	(*(volatile uint32_t *)(_base + _reg))
 #define REG(_tmr, _reg)		_REG32(io_timers[_tmr].base, _reg)
 
@@ -499,3 +503,4 @@ int up_input_capture_get_stats(unsigned channel, input_capture_stats_t *stats, b
 
 	return rv;
 }
+#endif // defined(BOARD_HAS_CAPTURE)

src/drivers/stm32/drv_io_timer.c

@@ -132,6 +132,10 @@ typedef uint8_t io_timer_allocation_t; /* big enough to hold MAX_IO_TIMERS */
 
 static io_timer_allocation_t once = 0;
 
+#if defined(BOARD_HAS_CAPTURE)
+
+/* Stats and handlers are only useful for Capture */
+
 typedef struct channel_stat_t {
 	uint32_t 			isr_cout;
 	uint32_t 			overflows;
@@ -143,10 +147,12 @@ static struct channel_handler_entry {
 	channel_handler_t callback;
 	void			  *context;
 } channel_handlers[MAX_TIMER_IO_CHANNELS];
+#endif // defined(BOARD_HAS_CAPTURE)
 
 
 static int io_timer_handler(uint16_t timer_index)
 {
+#if defined(BOARD_HAS_CAPTURE)
 	/* Read the count at the time of the interrupt */
 
 	uint16_t count = rCNT(timer_index);
@@ -198,6 +204,7 @@ static int io_timer_handler(uint16_t timer_index)
 	/* Clear all the SR bits for interrupt enabled channels only */
 
 	rSR(timer_index) = ~(statusr & (enabled | enabled << 8));
+#endif // defined(BOARD_HAS_CAPTURE)
 	return 0;
 }
 
@@ -651,10 +658,13 @@ int io_timer_channel_init(unsigned channel, io_timer_channel_mode_t mode,
 		gpio = timer_io_channels[channel].gpio_in;
 		break;
 
+#if defined(BOARD_HAS_CAPTURE)
+
 	case IOTimerChanMode_Capture:
 		setbits = CCMR_C1_CAPTURE_INIT;
 		gpio = timer_io_channels[channel].gpio_in;
 		break;
+#endif
 
 	case IOTimerChanMode_NotUsed:
 		setbits = 0;
@@ -721,9 +731,13 @@ int io_timer_channel_init(unsigned channel, io_timer_channel_mode_t mode,
 		rvalue |=  setbits;
 		rCCER(timer) = rvalue;
 
+#if !defined(BOARD_HAS_CAPTURE)
+		UNUSED(dier_setbits);
+#else
 		channel_handlers[channel].callback = channel_handler;
 		channel_handlers[channel].context = context;
 		rDIER(timer) |= dier_setbits << shifts;
+#endif
 		px4_leave_critical_section(flags);
 	}