Some tag might get deactivated after some read or write tentative. This may happen for example with Mifare Ultralight C tag when trying to read the last 4 blocks (starting block 0x2c) configured as write only. NFC_CMD_ACTIVATE_TARGET will try to reselect the tag in order to detect if it got remove from the field or if it is still present.
Signed-off-by: Christophe Ricard <[email protected]> --- include/uapi/linux/nfc.h | 1 + net/nfc/netlink.c | 30 ++++++++++++++++++++++++++++++ 2 files changed, 31 insertions(+) diff --git a/include/uapi/linux/nfc.h b/include/uapi/linux/nfc.h index 19a75da..3c5efb1 100644 --- a/include/uapi/linux/nfc.h +++ b/include/uapi/linux/nfc.h @@ -116,6 +116,7 @@ enum nfc_commands { NFC_EVENT_SE_TRANSACTION, NFC_CMD_GET_SE, NFC_CMD_SE_IO, + NFC_CMD_ACTIVATE_TARGET, /* private: internal use only */ __NFC_CMD_AFTER_LAST }; diff --git a/net/nfc/netlink.c b/net/nfc/netlink.c index 43cb1c1..9581831 100644 --- a/net/nfc/netlink.c +++ b/net/nfc/netlink.c @@ -810,6 +810,31 @@ out: return rc; } +static int nfc_genl_activate_target(struct sk_buff *skb, struct genl_info *info) +{ + struct nfc_dev *dev; + u32 device_idx, target_idx, protocol; + int rc; + + if (!info->attrs[NFC_ATTR_DEVICE_INDEX]) + return -EINVAL; + + device_idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]); + + dev = nfc_get_device(device_idx); + if (!dev) + return -ENODEV; + + target_idx = nla_get_u32(info->attrs[NFC_ATTR_TARGET_INDEX]); + protocol = nla_get_u32(info->attrs[NFC_ATTR_PROTOCOLS]); + + nfc_deactivate_target(dev, target_idx); + rc = nfc_activate_target(dev, target_idx, protocol); + + nfc_put_device(dev); + return 0; +} + static int nfc_genl_dep_link_up(struct sk_buff *skb, struct genl_info *info) { struct nfc_dev *dev; @@ -1455,6 +1480,11 @@ static const struct genl_ops nfc_genl_ops[] = { .doit = nfc_genl_se_io, .policy = nfc_genl_policy, }, + { + .cmd = NFC_CMD_ACTIVATE_TARGET, + .doit = nfc_genl_activate_target, + .policy = nfc_genl_policy, + }, }; -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
