altos: Add timeout in MS5607 get_sample code

MISO is supposed to rise when the sample value is ready, but sometimes
we miss the interrupt which should be generated. I spent a day
attempting to fix this, but was unable to make it 100%. Instead, add a
10ms timeout, which is longer than the sample time (8.2ms), and then
read MISO directly. If the interrupt fires, we'll read a bit sooner.

Signed-off-by: Keith Packard <keithp@keithp.com>

diff --git a/src/drivers/ao_ms5607.c b/src/drivers/ao_ms5607.c
index 895e1d3492173815ef2100e94a3be32cb5007795..dce7c0e6a3c5a5de8af7ccf570ee6b43c0c5f9b9 100644 (file)
--- a/src/drivers/ao_ms5607.c
+++ b/src/drivers/ao_ms5607.c
@@ -148,7 +148,6 @@ static void
 ao_ms5607_isr(void)
 {
        ao_exti_disable(AO_MS5607_MISO_PORT, AO_MS5607_MISO_PIN);
-       ao_ms5607_done = 1;
        ao_wakeup((void *) &ao_ms5607_done);
 }
 
@@ -156,26 +155,27 @@ static uint32_t
 ao_ms5607_get_sample(uint8_t cmd) {
        uint8_t reply[4];
 
-       ao_ms5607_done = 0;
-
        ao_ms5607_start();
-       ao_spi_send(&cmd, 1, AO_MS5607_SPI_INDEX);
 
        ao_exti_enable(AO_MS5607_MISO_PORT, AO_MS5607_MISO_PIN);
 
+       ao_spi_send(&cmd, 1, AO_MS5607_SPI_INDEX);
+
 #if AO_MS5607_PRIVATE_PINS
-       ao_spi_put(AO_MS5607_SPI_INDEX);
+       ao_spi_put_pins(AO_MS5607_SPI_INDEX);
 #endif
        ao_arch_block_interrupts();
-       while (!ao_gpio_get(AO_MS5607_MISO_PORT, AO_MS5607_MISO_PIN) &&
-              !ao_ms5607_done)
-       {
+#if !HAS_TASK
+#define ao_sleep_for(a,t) ao_sleep(a)
+#endif
+       while (!ao_gpio_get(AO_MS5607_MISO_PORT, AO_MS5607_MISO_PIN)) {
                if (ao_sleep_for((void *) &ao_ms5607_done, AO_MS_TO_TICKS(10)))
                        break;
        }
+       ao_exti_disable(AO_MS5607_MISO_PORT, AO_MS5607_MISO_PIN);
        ao_arch_release_interrupts();
 #if AO_MS5607_PRIVATE_PINS
-       ao_gpio_set(AO_MS5607_CS_PORT, AO_MS5607_CS_PIN, 1);
+       ao_spi_clr_cs(AO_MS5607_CS_PORT, 1 << (AO_MS5607_CS_PIN));
 #else
        ao_ms5607_stop();
 #endif