From 1a3dfad34110158d08044bb4901e680480fe19f7 Mon Sep 17 00:00:00 2001
From: Rahix <rahix@rahix.de>
Date: Thu, 26 Dec 2019 12:47:28 +0100
Subject: [PATCH] fix(bhi160): Fix interrupt behavior during initialization
As discussed in issue card10/firmware#133, the BHI160 changes its
interrupt behavior during initialization. In commit 2f56ff36403c
("fix(bhi160): Call bhy_mapping_matrix_set twice for the first time")
a quick workaround for this issue was added. Replace this hack with
a proper fix by reconfiguring the interrupt on the host side according
to the specification.
(Finally) fixes card10/firmware#133.
Fixes: 2f56ff36403c ("fix(bhi160): Call bhy_mapping_matrix_set twice for the first time")
Link: https://git.card10.badge.events.ccc.de/card10/firmware/issues/133#note_5894
Signed-off-by: Rahix <rahix@rahix.de>
---
epicardium/modules/bhi.c | 25 +++++++++++++++++--------
1 file changed, 17 insertions(+), 8 deletions(-)
diff --git a/epicardium/modules/bhi.c b/epicardium/modules/bhi.c
index 9891c0a4..3ef515b8 100644
--- a/epicardium/modules/bhi.c
+++ b/epicardium/modules/bhi.c
@@ -405,12 +405,20 @@ void vBhi160Task(void *pvParameters)
memset(bhi160_streams, 0x00, sizeof(bhi160_streams));
- /* Install interrupt callback */
+ /*
+ * The BHI160, coming out of power-on-reset will hold its interrupt line
+ * high until a firmware image is loaded. Once that firmware is loaded
+ * and running, the interrupt line is deasserted and from then on,
+ * interrupts are signaled using a rising edge.
+ *
+ * So, initially we need to configure the IRQ for a falling edge, load
+ * the firmware and then reconfigure for a rising edge.
+ */
GPIO_Config(&bhi160_interrupt_pin);
GPIO_RegisterCallback(
&bhi160_interrupt_pin, bhi160_interrupt_callback, NULL
);
- GPIO_IntConfig(&bhi160_interrupt_pin, GPIO_INT_EDGE, GPIO_INT_RISING);
+ GPIO_IntConfig(&bhi160_interrupt_pin, GPIO_INT_EDGE, GPIO_INT_FALLING);
GPIO_IntEnable(&bhi160_interrupt_pin);
NVIC_SetPriority(
(IRQn_Type)MXC_GPIO_GET_IRQ(bhi160_interrupt_pin.port), 2
@@ -424,17 +432,18 @@ void vBhi160Task(void *pvParameters)
vTaskDelay(portMAX_DELAY);
}
- /* Wait for first interrupt */
+ /* Wait for first interrupt, a falling edge */
hwlock_release(HWLOCK_I2C);
ulTaskNotifyTake(pdTRUE, pdMS_TO_TICKS(100));
hwlock_acquire(HWLOCK_I2C);
+ /*
+ * The firmware is now loaded; as stated above, we now need to
+ * reconfigure the IRQ for a rising edge.
+ */
+ GPIO_IntConfig(&bhi160_interrupt_pin, GPIO_INT_EDGE, GPIO_INT_RISING);
+
/* Remap axes to match card10 layout */
- /* Due to a known issue (#133) the first call to
- * bhy_mapping_matrix_set might fail. */
- bhy_mapping_matrix_set(
- PHYSICAL_SENSOR_INDEX_ACC, bhi160_mapping_matrix
- );
bhy_mapping_matrix_set(
PHYSICAL_SENSOR_INDEX_ACC, bhi160_mapping_matrix
);
--
GitLab