From: Michael Walle Date: Mon, 27 Jun 2022 17:06:42 +0000 (+0200) Subject: NFC: nxp-nci: Don't issue a zero length i2c_master_read() X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=eaf7e6fe4b07f979845484f112493a4203ed55e4;p=linux.git NFC: nxp-nci: Don't issue a zero length i2c_master_read() 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 Reviewed-by: Krzysztof Kozlowski Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/nfc/nxp-nci/i2c.c b/drivers/nfc/nxp-nci/i2c.c index 7e451c10985df..e8f3b35afbee4 100644 --- a/drivers/nfc/nxp-nci/i2c.c +++ b/drivers/nfc/nxp-nci/i2c.c @@ -162,6 +162,9 @@ static int nxp_nci_i2c_nci_read(struct nxp_nci_i2c_phy *phy, skb_put_data(*skb, (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,