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 <christophe-h.ricard@xxxxxx>
---
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 majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
