From 8ffa2f9b9605188a7a5f4431d6eafecf525810e6 Mon Sep 17 00:00:00 2001
From: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Date: Tue, 20 Oct 2015 15:55:08 -0400
Subject: [PATCH] hidpp20: retrieve the protocol version in hidpp20.c

We need hidpp20 to handle the list of available features. So we need to be
sure in hidpp20 that we are talking to a hidpp20 device.

Move the version retrieval in hidpp20 where it makes sense.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
---
 src/driver-hidpp20.c | 15 ++-------------
 src/hidpp20.c        | 13 +++++++++++++
 src/hidpp20.h        |  2 ++
 3 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/src/driver-hidpp20.c b/src/driver-hidpp20.c
index ed889edb..a84f5496 100644
--- a/src/driver-hidpp20.c
+++ b/src/driver-hidpp20.c
@@ -54,8 +54,6 @@
 
 struct hidpp20drv_data {
 	struct hidpp20_device *dev;
-	unsigned proto_major;
-	unsigned proto_minor;
 	unsigned long capabilities;
 	unsigned num_sensors;
 	struct hidpp20_sensor *sensors;
@@ -496,19 +494,10 @@ hidpp20drv_probe(struct ratbag_device *device)
 	}
 
 	drv_data->dev = dev;
-	drv_data->proto_major = 1;
-	drv_data->proto_minor = 0;
 
-	rc = hidpp20_root_get_protocol_version(drv_data->dev, &drv_data->proto_major, &drv_data->proto_minor);
-	if (rc) {
-		/* communication error, best to ignore the device */
-		rc = -EINVAL;
-		goto err;
-	}
+	log_debug(device->ratbag, "'%s' is using protocol v%d.%d\n", ratbag_device_get_name(device), dev->proto_major, dev->proto_minor);
 
-	log_debug(device->ratbag, "'%s' is using protocol v%d.%d\n", ratbag_device_get_name(device), drv_data->proto_major, drv_data->proto_minor);
-
-	if (drv_data->proto_major >= 2) {
+	if (dev->proto_major >= 2) {
 		rc = hidpp20drv_20_probe(device);
 		if (rc)
 			goto err;
diff --git a/src/hidpp20.c b/src/hidpp20.c
index 954704cc..f02aa704 100644
--- a/src/hidpp20.c
+++ b/src/hidpp20.c
@@ -915,13 +915,26 @@ struct hidpp20_device *
 hidpp20_device_new(const struct hidpp_device *base, unsigned int idx)
 {
 	struct hidpp20_device *dev;
+	int rc;
 
 	dev = zalloc(sizeof(*dev));
 
 	dev->index = idx;
 	dev->base = *base;
 
+	dev->proto_major = 1;
+	dev->proto_minor = 0;
+
+	rc = hidpp20_root_get_protocol_version(dev, &dev->proto_major, &dev->proto_minor);
+	if (rc) {
+		/* communication error, best to ignore the device */
+		goto err;
+	}
+
 	return dev;
+err:
+	free(dev);
+	return NULL;
 }
 
 void
diff --git a/src/hidpp20.h b/src/hidpp20.h
index ccab08dd..2abc41bc 100644
--- a/src/hidpp20.h
+++ b/src/hidpp20.h
@@ -49,6 +49,8 @@ union hidpp20_message {
 struct hidpp20_device {
 	struct hidpp_device base;
 	unsigned int index;
+	unsigned proto_major;
+	unsigned proto_minor;
 };
 
 int hidpp20_request_command(struct hidpp20_device *dev, union hidpp20_message *msg);