This is a note to let you know that I've just added the patch titled
NFC: nxp-nci: Don't issue a zero length i2c_master_read()
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
nfc-nxp-nci-don-t-issue-a-zero-length-i2c_master_read.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From eddd95b9423946aaacb55cac6a9b2cea8ab944fc Mon Sep 17 00:00:00 2001
From: Michael Walle <michael@xxxxxxxx>
Date: Mon, 27 Jun 2022 19:06:42 +0200
Subject: NFC: nxp-nci: Don't issue a zero length i2c_master_read()
From: Michael Walle <michael@xxxxxxxx>
commit eddd95b9423946aaacb55cac6a9b2cea8ab944fc upstream.
There are packets which doesn't have a payload. In that case, the second
i2c_master_read() will have a zero length. But because the NFC
controller doesn't have any data left, it will NACK the I2C read and
-ENXIO will be returned. In case there is no payload, just skip the
second i2c master read.
Fixes: 6be88670fc59 ("NFC: nxp-nci_i2c: Add I2C support to NXP NCI driver")
Signed-off-by: Michael Walle <michael@xxxxxxxx>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/nfc/nxp-nci/i2c.c | 3 +++
1 file changed, 3 insertions(+)
--- a/drivers/nfc/nxp-nci/i2c.c
+++ b/drivers/nfc/nxp-nci/i2c.c
@@ -180,6 +180,9 @@ static int nxp_nci_i2c_nci_read(struct n
memcpy(skb_put(*skb, NCI_CTRL_HDR_SIZE), (void *) &header,
NCI_CTRL_HDR_SIZE);
+ if (!header.plen)
+ return 0;
+
r = i2c_master_recv(client, skb_put(*skb, header.plen), header.plen);
if (r != header.plen) {
nfc_err(&client->dev,
Patches currently in stable-queue which might be from michael@xxxxxxxx are
queue-4.9/nfc-nxp-nci-don-t-issue-a-zero-length-i2c_master_read.patch
