virtio: blk: Fix converting the vendor id to a string

Currently we are trying to work out if the vendor id is from
a virtio-mmio device and then casting a u32 to a char* and using
it as a C-string. By chance there is usually a zero after the u32
and it works.

Since the vendor id we are trying to convert to a string is QEMU's
just define a value for the QEMU vendor id, check if the vendor
id matches and then use a predefined string for "QEMU".

I don't think we should have been assumming all virtio-mmio vendor
ids are printable ASCII chars in the first place so do this special
casing just for QEMU. If the vendor id isn't QEMU print the hex
value of it.

Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Signed-off-by: Daniel Palmer <daniel@thingy.jp>

diff --git a/drivers/virtio/virtio_blk.c b/drivers/virtio/virtio_blk.c
index 45fb596a3308f2f5f1632f1a8235a085ca106481..94968ef1c759ef475604dd023482134c351d62c9 100644 (file)
--- a/drivers/virtio/virtio_blk.c
+++ b/drivers/virtio/virtio_blk.c
@@ -231,14 +231,11 @@ static int virtio_blk_bind(struct udevice *dev)
                return devnum;
        desc->devnum = devnum;
        desc->part_type = PART_TYPE_UNKNOWN;
-       /*
-        * virtio mmio transport supplies string identification for us,
-        * while pci trnasport uses a 2-byte subvendor value.
-        */
-       if (uc_priv->vendor >> 16)
-               sprintf(desc->vendor, "%s", (char *)&uc_priv->vendor);
+
+       if (uc_priv->vendor == VIRTIO_VENDOR_QEMU)
+               strcpy(desc->vendor, "QEMU");
        else
-               sprintf(desc->vendor, "%04x", uc_priv->vendor);
+               sprintf(desc->vendor, "%08x", uc_priv->vendor);
        desc->bdev = dev;
 
        /* Indicate what driver features we support */

diff --git a/include/virtio.h b/include/virtio.h
index 17f894a79e3162d246ec9c160678386fd25ac023..3edf023463d7ec52fd0a48f8ba15157fd0a6ee73 100644 (file)
--- a/include/virtio.h
+++ b/include/virtio.h
@@ -25,6 +25,9 @@
 #include <linux/bitops.h>
 #include <linux/bug.h>
 #include <linux/typecheck.h>
+
+#define VIRTIO_VENDOR_QEMU     0x554d4551
+
 #define VIRTIO_ID_NET          1 /* virtio net */
 #define VIRTIO_ID_BLOCK                2 /* virtio block */
 #define VIRTIO_ID_RNG          4 /* virtio rng */