NFC: Add firmware upload netlink command

As several NFC chipsets can have their firmwares upgraded and
reflashed, this patchset adds a new netlink command to trigger
that the driver loads or flashes a new firmware. This will allows
userspace triggered firmware upgrade through netlink.
The firmware name or hint is passed as a parameter, and the driver
will eventually fetch the firmware binary through the request_firmware
API.
The cmd can only be executed when the nfc dev is not in use. Actual
firmware loading/flashing is an asynchronous operation. Result of the
operation shall send a new event up to user space through the nfc dev
multicast socket. During operation, the nfc dev is not openable and
thus not usable.

Signed-off-by: Eric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 63 insertions, 0 deletions

diff --git a/net/nfc/netlink.c b/net/nfc/netlink.c
index f0c4d61f37c0..1deadad9a285 100644
--- a/net/nfc/netlink.c
+++ b/net/nfc/netlink.c
@@ -56,6 +56,8 @@ static const struct nla_policy nfc_genl_policy[NFC_ATTR_MAX + 1] = {
         [NFC_ATTR_LLC_PARAM_RW] = { .type = NLA_U8 },
         [NFC_ATTR_LLC_PARAM_MIUX] = { .type = NLA_U16 },
         [NFC_ATTR_LLC_SDP] = { .type = NLA_NESTED },
+        [NFC_ATTR_FIRMWARE_NAME] = { .type = NLA_STRING,
+                                     .len = NFC_FIRMWARE_NAME_MAXSIZE },
 };
 
 static const struct nla_policy nfc_sdp_genl_policy[NFC_SDP_ATTR_MAX + 1] = {
@@ -1025,6 +1027,62 @@ exit:
         return rc;
 }
 
+static int nfc_genl_fw_upload(struct sk_buff *skb, struct genl_info *info)
+{
+        struct nfc_dev *dev;
+        int rc;
+        u32 idx;
+        char firmware_name[NFC_FIRMWARE_NAME_MAXSIZE + 1];
+
+        if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
+                return -EINVAL;
+
+        idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
+
+        dev = nfc_get_device(idx);
+        if (!dev)
+                return -ENODEV;
+
+        nla_strlcpy(firmware_name, info->attrs[NFC_ATTR_FIRMWARE_NAME],
+                    sizeof(firmware_name));
+
+        rc = nfc_fw_upload(dev, firmware_name);
+
+        nfc_put_device(dev);
+        return rc;
+}
+
+int nfc_genl_fw_upload_done(struct nfc_dev *dev, const char *firmware_name)
+{
+        struct sk_buff *msg;
+        void *hdr;
+
+        msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+        if (!msg)
+                return -ENOMEM;
+
+        hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
+                          NFC_CMD_FW_UPLOAD);
+        if (!hdr)
+                goto free_msg;
+
+        if (nla_put_string(msg, NFC_ATTR_FIRMWARE_NAME, firmware_name) ||
+            nla_put_u32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx))
+                goto nla_put_failure;
+
+        genlmsg_end(msg, hdr);
+
+        genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_KERNEL);
+
+        return 0;
+
+nla_put_failure:
+        genlmsg_cancel(msg, hdr);
+free_msg:
+        nlmsg_free(msg);
+        return -EMSGSIZE;
+}
+
 static struct genl_ops nfc_genl_ops[] = {
         {
                 .cmd = NFC_CMD_GET_DEVICE,
@@ -1084,6 +1142,11 @@ static struct genl_ops nfc_genl_ops[] = {
                 .doit = nfc_genl_llc_sdreq,
                 .policy = nfc_genl_policy,
         },
+        {
+                .cmd = NFC_CMD_FW_UPLOAD,
+                .doit = nfc_genl_fw_upload,
+                .policy = nfc_genl_policy,
+        },
 };