From: Daniel Elstner <redacted>
Date: Tue, 22 Dec 2015 14:52:40 +0000 (+0100)
Subject: sysclk-lwla: Attempt initialization three times
X-Git-Tag: libsigrok-0.4.0~63
X-Git-Url: https://sigrok.org/gitaction?a=commitdiff_plain;h=e35a4592488d7492a46921dd8bd130eae5faf11a;p=libsigrok.git

sysclk-lwla: Attempt initialization three times

This is a desperate measure to improve the success rate of device
initialization even after it got into a bad state. Combine this
with a reduced USB timeout (1 second) so that if it fails, it fails
quickly. Also ignore USB errors from the initial dummy read of the
device test ID.
---

diff --git a/src/hardware/sysclk-lwla/api.c b/src/hardware/sysclk-lwla/api.c
index 36c9ee60..20e30d1e 100644
--- a/src/hardware/sysclk-lwla/api.c
+++ b/src/hardware/sysclk-lwla/api.c
@@ -289,6 +289,7 @@ static int dev_open(struct sr_dev_inst *sdi)
 	struct drv_context *drvc;
 	struct dev_context *devc;
 	struct sr_usb_dev_inst *usb;
+	int i;
 	int ret;
 
 	drvc = sdi->driver->context;
@@ -304,54 +305,58 @@ static int dev_open(struct sr_dev_inst *sdi)
 		return SR_ERR;
 	}
 
-	ret = sr_usb_open(drvc->sr_ctx->libusb_ctx, usb);
-	if (ret != SR_OK)
-		return ret;
+	/* Try the whole shebang three times, fingers crossed. */
+	for (i = 0; i < 3; i++) {
+		ret = sr_usb_open(drvc->sr_ctx->libusb_ctx, usb);
+		if (ret != SR_OK)
+			return ret;
 
-	ret = libusb_set_configuration(usb->devhdl, USB_CONFIG);
-	if (ret != LIBUSB_SUCCESS) {
-		sr_err("Failed to set USB configuration: %s.",
-			libusb_error_name(ret));
-		sr_usb_close(usb);
-		return SR_ERR;
-	}
+		ret = libusb_set_configuration(usb->devhdl, USB_CONFIG);
+		if (ret != LIBUSB_SUCCESS) {
+			sr_err("Failed to set USB configuration: %s.",
+				libusb_error_name(ret));
+			sr_usb_close(usb);
+			return SR_ERR;
+		}
 
-	ret = libusb_claim_interface(usb->devhdl, USB_INTERFACE);
-	if (ret != LIBUSB_SUCCESS) {
-		sr_err("Failed to claim interface: %s.",
-			libusb_error_name(ret));
-		sr_usb_close(usb);
-		return SR_ERR;
-	}
+		ret = libusb_claim_interface(usb->devhdl, USB_INTERFACE);
+		if (ret != LIBUSB_SUCCESS) {
+			sr_err("Failed to claim interface: %s.",
+				libusb_error_name(ret));
+			sr_usb_close(usb);
+			return SR_ERR;
+		}
 
-	ret = drain_usb(usb, EP_REPLY);
-	if (ret != SR_OK) {
-		sr_usb_close(usb);
-		return ret;
-	}
-	/* This delay appears to be necessary for reliable operation. */
-	g_usleep(30 * 1000);
+		ret = drain_usb(usb, EP_REPLY);
+		if (ret != SR_OK) {
+			sr_usb_close(usb);
+			return ret;
+		}
+		/* This delay appears to be necessary for reliable operation. */
+		g_usleep(30 * 1000);
 
-	sdi->status = SR_ST_ACTIVE;
+		sdi->status = SR_ST_ACTIVE;
 
-	devc->active_fpga_config = FPGA_NOCONF;
-	devc->short_transfer_quirk = FALSE;
-	devc->state = STATE_IDLE;
+		devc->active_fpga_config = FPGA_NOCONF;
+		devc->short_transfer_quirk = FALSE;
+		devc->state = STATE_IDLE;
 
-	ret = (*devc->model->apply_fpga_config)(sdi);
+		ret = (*devc->model->apply_fpga_config)(sdi);
 
-	if (ret == SR_OK)
-		ret = (*devc->model->device_init_check)(sdi);
+		if (ret == SR_OK)
+			ret = (*devc->model->device_init_check)(sdi);
+		if (ret == SR_OK)
+			break;
 
-	if (ret != SR_OK) {
+		/* Rinse and repeat. */
 		sdi->status = SR_ST_INACTIVE;
 		sr_usb_close(usb);
-		return ret;
 	}
-	if (devc->short_transfer_quirk)
+
+	if (ret == SR_OK && devc->short_transfer_quirk)
 		sr_warn("Short transfer quirk detected! "
 			"Memory reads will be slow.");
-	return SR_OK;
+	return ret;
 }
 
 /* Shutdown and close device.
diff --git a/src/hardware/sysclk-lwla/lwla1016.c b/src/hardware/sysclk-lwla/lwla1016.c
index 0e30bf8e..61435553 100644
--- a/src/hardware/sysclk-lwla/lwla1016.c
+++ b/src/hardware/sysclk-lwla/lwla1016.c
@@ -274,9 +274,7 @@ static int device_init_check(const struct sr_dev_inst *sdi)
 
 	const unsigned int test_count = 24;
 
-	ret = lwla_read_reg(sdi->conn, REG_TEST_ID, &value);
-	if (ret != SR_OK)
-		return ret;
+	lwla_read_reg(sdi->conn, REG_TEST_ID, &value);
 
 	/* Ignore the value returned by the first read. */
 	ret = lwla_read_reg(sdi->conn, REG_TEST_ID, &value);
diff --git a/src/hardware/sysclk-lwla/lwla1034.c b/src/hardware/sysclk-lwla/lwla1034.c
index 62de549a..d64641ea 100644
--- a/src/hardware/sysclk-lwla/lwla1034.c
+++ b/src/hardware/sysclk-lwla/lwla1034.c
@@ -358,9 +358,7 @@ static int device_init_check(const struct sr_dev_inst *sdi)
 	uint64_t value;
 	int ret;
 
-	ret = read_long_reg(sdi->conn, LREG_TEST_ID, &value);
-	if (ret != SR_OK)
-		return ret;
+	read_long_reg(sdi->conn, LREG_TEST_ID, &value);
 
 	/* Ignore the value returned by the first read. */
 	ret = read_long_reg(sdi->conn, LREG_TEST_ID, &value);
diff --git a/src/hardware/sysclk-lwla/protocol.h b/src/hardware/sysclk-lwla/protocol.h
index adb08b8e..5bdc71fe 100644
--- a/src/hardware/sysclk-lwla/protocol.h
+++ b/src/hardware/sysclk-lwla/protocol.h
@@ -59,7 +59,7 @@ enum {
 enum {
 	USB_CONFIG	= 1,
 	USB_INTERFACE	= 0,
-	USB_TIMEOUT_MS	= 3000,
+	USB_TIMEOUT_MS	= 1000,
 };
 
 /** USB device end points.