Add retry logic to get_status() function
In case of chip is asleep then Linux kernel driver returns
EAGAIN error code for get_status operation.
In this case we retry the operation again. Currently limit is set to
10 retries.
Remove retry logic from clear_status() that is duplicated now.
Test: harness tests pass
Bug: 73959155
Change-Id: I72ae3e0b7f6002a61147bbd96d668a5f690c135c
diff --git a/libnos_transport/transport.c b/libnos_transport/transport.c
index c328c18..140d257 100644
--- a/libnos_transport/transport.c
+++ b/libnos_transport/transport.c
@@ -16,6 +16,7 @@
#include <nos/transport.h>
+#include <errno.h>
#include <stdarg.h>
#include <stdint.h>
#include <stdlib.h>
@@ -62,14 +63,33 @@
uint8_t buf[6];
uint32_t command = CMD_ID(app_id) | CMD_IS_READ | CMD_TRANSPORT;
- if (0 != dev->ops.read(dev->ctx, command, buf, sizeof(buf))) {
- NLOGV("Failed to read device status");
+ uint16_t retries = 10;
+ while (retries--) {
+ int err = dev->ops.read(dev->ctx, command, buf, sizeof(buf));
+
+ if (err == 0) {
+ /* The read operation is successful */
+ *status = *(uint32_t *)buf;
+ *ulen = *(uint16_t *)(buf + 4);
+
+ return 0;
+ }
+
+ if (err == -EAGAIN) {
+ /* Linux driver returns EAGAIN error if Citadel chip is asleep.
+ * Give to the chip a little bit of time to awake and retry reading
+ * status again. */
+ usleep(5000);
+ continue;
+ }
+
+ /* Citadel driver returned an error */
+ NLOGE("Failed to read device status: %d", err);
return -1;
}
- *status = *(uint32_t *)buf;
- *ulen = *(uint16_t *)(buf + 4);
- return 0;
+ NLOGE("Failed to read device status");
+ return -1;
}
static int clear_status(const struct nos_device *dev, uint8_t app_id)
@@ -94,18 +114,8 @@
uint32_t status;
uint16_t ulen;
uint32_t poll_count = 0;
- uint16_t retries = 10;
- /* Make sure it's idle */
- while (retries) {
- if (get_status(dev, app_id, &status, &ulen) == 0) {
- break;
- }
- --retries;
- usleep(5000);
- }
- if (!retries) {
- NLOGE("Failed to read device status");
+ if (get_status(dev, app_id, &status, &ulen) != 0) {
return APP_ERROR_IO;
}
NLOGV("%d: query status 0x%08x ulen 0x%04x", __LINE__, status, ulen);