diff options
Diffstat (limited to 'drivers/nfc/mei_phy.c')
| -rw-r--r-- | drivers/nfc/mei_phy.c | 417 |
1 files changed, 417 insertions, 0 deletions
diff --git a/drivers/nfc/mei_phy.c b/drivers/nfc/mei_phy.c new file mode 100644 index 0000000..49bdc2f --- /dev/null +++ b/drivers/nfc/mei_phy.c @@ -0,0 +1,417 @@ +/* + * MEI Library for mei bus nfc device access + * + * Copyright (C) 2013 Intel Corporation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/nfc.h> + +#include "mei_phy.h" + +struct mei_nfc_hdr { + u8 cmd; + u8 status; + u16 req_id; + u32 reserved; + u16 data_size; +} __packed; + +struct mei_nfc_cmd { + struct mei_nfc_hdr hdr; + u8 sub_command; + u8 data[]; +} __packed; + +struct mei_nfc_reply { + struct mei_nfc_hdr hdr; + u8 sub_command; + u8 reply_status; + u8 data[]; +} __packed; + +struct mei_nfc_if_version { + u8 radio_version_sw[3]; + u8 reserved[3]; + u8 radio_version_hw[3]; + u8 i2c_addr; + u8 fw_ivn; + u8 vendor_id; + u8 radio_type; +} __packed; + +struct mei_nfc_connect { + u8 fw_ivn; + u8 vendor_id; +} __packed; + +struct mei_nfc_connect_resp { + u8 fw_ivn; + u8 vendor_id; + u16 me_major; + u16 me_minor; + u16 me_hotfix; + u16 me_build; +} __packed; + + +#define MEI_NFC_CMD_MAINTENANCE 0x00 +#define MEI_NFC_CMD_HCI_SEND 0x01 +#define MEI_NFC_CMD_HCI_RECV 0x02 + +#define MEI_NFC_SUBCMD_CONNECT 0x00 +#define MEI_NFC_SUBCMD_IF_VERSION 0x01 + +#define MEI_NFC_MAX_READ (MEI_NFC_HEADER_SIZE + MEI_NFC_MAX_HCI_PAYLOAD) + +#define MEI_DUMP_SKB_IN(info, skb) \ +do { \ + pr_debug("%s:\n", info); \ + print_hex_dump_debug("mei in : ", DUMP_PREFIX_OFFSET, \ + 16, 1, (skb)->data, (skb)->len, false); \ +} while (0) + +#define MEI_DUMP_SKB_OUT(info, skb) \ +do { \ + pr_debug("%s:\n", info); \ + print_hex_dump_debug("mei out: ", DUMP_PREFIX_OFFSET, \ + 16, 1, (skb)->data, (skb)->len, false); \ +} while (0) + +#define MEI_DUMP_NFC_HDR(info, _hdr) \ +do { \ + pr_debug("%s:\n", info); \ + pr_debug("cmd=%02d status=%d req_id=%d rsvd=%d size=%d\n", \ + (_hdr)->cmd, (_hdr)->status, (_hdr)->req_id, \ + (_hdr)->reserved, (_hdr)->data_size); \ +} while (0) + +static int mei_nfc_if_version(struct nfc_mei_phy *phy) +{ + + struct mei_nfc_cmd cmd; + struct mei_nfc_reply *reply = NULL; + struct mei_nfc_if_version *version; + size_t if_version_length; + int bytes_recv, r; + + pr_info("%s\n", __func__); + + memset(&cmd, 0, sizeof(struct mei_nfc_cmd)); + cmd.hdr.cmd = MEI_NFC_CMD_MAINTENANCE; + cmd.hdr.data_size = 1; + cmd.sub_command = MEI_NFC_SUBCMD_IF_VERSION; + + MEI_DUMP_NFC_HDR("version", &cmd.hdr); + r = mei_cldev_send(phy->cldev, (u8 *)&cmd, sizeof(struct mei_nfc_cmd)); + if (r < 0) { + pr_err("Could not send IF version cmd\n"); + return r; + } + + /* to be sure on the stack we alloc memory */ + if_version_length = sizeof(struct mei_nfc_reply) + + sizeof(struct mei_nfc_if_version); + + reply = kzalloc(if_version_length, GFP_KERNEL); + if (!reply) + return -ENOMEM; + + bytes_recv = mei_cldev_recv(phy->cldev, (u8 *)reply, if_version_length); + if (bytes_recv < 0 || bytes_recv < if_version_length) { + pr_err("Could not read IF version\n"); + r = -EIO; + goto err; + } + + version = (struct mei_nfc_if_version *)reply->data; + + phy->fw_ivn = version->fw_ivn; + phy->vendor_id = version->vendor_id; + phy->radio_type = version->radio_type; + +err: + kfree(reply); + return r; +} + +static int mei_nfc_connect(struct nfc_mei_phy *phy) +{ + struct mei_nfc_cmd *cmd, *reply; + struct mei_nfc_connect *connect; + struct mei_nfc_connect_resp *connect_resp; + size_t connect_length, connect_resp_length; + int bytes_recv, r; + + pr_info("%s\n", __func__); + + connect_length = sizeof(struct mei_nfc_cmd) + + sizeof(struct mei_nfc_connect); + + connect_resp_length = sizeof(struct mei_nfc_cmd) + + sizeof(struct mei_nfc_connect_resp); + + cmd = kzalloc(connect_length, GFP_KERNEL); + if (!cmd) + return -ENOMEM; + connect = (struct mei_nfc_connect *)cmd->data; + + reply = kzalloc(connect_resp_length, GFP_KERNEL); + if (!reply) { + kfree(cmd); + return -ENOMEM; + } + + connect_resp = (struct mei_nfc_connect_resp *)reply->data; + + cmd->hdr.cmd = MEI_NFC_CMD_MAINTENANCE; + cmd->hdr.data_size = 3; + cmd->sub_command = MEI_NFC_SUBCMD_CONNECT; + connect->fw_ivn = phy->fw_ivn; + connect->vendor_id = phy->vendor_id; + + MEI_DUMP_NFC_HDR("connect request", &cmd->hdr); + r = mei_cldev_send(phy->cldev, (u8 *)cmd, connect_length); + if (r < 0) { + pr_err("Could not send connect cmd %d\n", r); + goto err; + } + + bytes_recv = mei_cldev_recv(phy->cldev, (u8 *)reply, + connect_resp_length); + if (bytes_recv < 0) { + r = bytes_recv; + pr_err("Could not read connect response %d\n", r); + goto err; + } + + MEI_DUMP_NFC_HDR("connect reply", &reply->hdr); + + pr_info("IVN 0x%x Vendor ID 0x%x\n", + connect_resp->fw_ivn, connect_resp->vendor_id); + + pr_info("ME FW %d.%d.%d.%d\n", + connect_resp->me_major, connect_resp->me_minor, + connect_resp->me_hotfix, connect_resp->me_build); + + r = 0; + +err: + kfree(reply); + kfree(cmd); + + return r; +} + +static int mei_nfc_send(struct nfc_mei_phy *phy, u8 *buf, size_t length) +{ + struct mei_nfc_hdr *hdr; + u8 *mei_buf; + int err; + + err = -ENOMEM; + mei_buf = kzalloc(length + MEI_NFC_HEADER_SIZE, GFP_KERNEL); + if (!mei_buf) + goto out; + + hdr = (struct mei_nfc_hdr *)mei_buf; + hdr->cmd = MEI_NFC_CMD_HCI_SEND; + hdr->status = 0; + hdr->req_id = phy->req_id; + hdr->reserved = 0; + hdr->data_size = length; + + MEI_DUMP_NFC_HDR("send", hdr); + + memcpy(mei_buf + MEI_NFC_HEADER_SIZE, buf, length); + err = mei_cldev_send(phy->cldev, mei_buf, length + MEI_NFC_HEADER_SIZE); + if (err < 0) + goto out; + + if (!wait_event_interruptible_timeout(phy->send_wq, + phy->recv_req_id == phy->req_id, HZ)) { + pr_err("NFC MEI command timeout\n"); + err = -ETIME; + } else { + phy->req_id++; + } +out: + kfree(mei_buf); + return err; +} + +/* + * Writing a frame must not return the number of written bytes. + * It must return either zero for success, or <0 for error. + * In addition, it must not alter the skb + */ +static int nfc_mei_phy_write(void *phy_id, struct sk_buff *skb) +{ + struct nfc_mei_phy *phy = phy_id; + int r; + + MEI_DUMP_SKB_OUT("mei frame sent", skb); + + r = mei_nfc_send(phy, skb->data, skb->len); + if (r > 0) + r = 0; + + return r; +} + +static int mei_nfc_recv(struct nfc_mei_phy *phy, u8 *buf, size_t length) +{ + struct mei_nfc_hdr *hdr; + int received_length; + + received_length = mei_cldev_recv(phy->cldev, buf, length); + if (received_length < 0) + return received_length; + + hdr = (struct mei_nfc_hdr *) buf; + + MEI_DUMP_NFC_HDR("receive", hdr); + if (hdr->cmd == MEI_NFC_CMD_HCI_SEND) { + phy->recv_req_id = hdr->req_id; + wake_up(&phy->send_wq); + + return 0; + } + + return received_length; +} + + +static void nfc_mei_rx_cb(struct mei_cl_device *cldev) +{ + struct nfc_mei_phy *phy = mei_cldev_get_drvdata(cldev); + struct sk_buff *skb; + int reply_size; + + if (!phy) + return; + + if (phy->hard_fault != 0) + return; + + skb = alloc_skb(MEI_NFC_MAX_READ, GFP_KERNEL); + if (!skb) + return; + + reply_size = mei_nfc_recv(phy, skb->data, MEI_NFC_MAX_READ); + if (reply_size < MEI_NFC_HEADER_SIZE) { + kfree_skb(skb); + return; + } + + skb_put(skb, reply_size); + skb_pull(skb, MEI_NFC_HEADER_SIZE); + + MEI_DUMP_SKB_IN("mei frame read", skb); + + nfc_hci_recv_frame(phy->hdev, skb); +} + +static int nfc_mei_phy_enable(void *phy_id) +{ + int r; + struct nfc_mei_phy *phy = phy_id; + + pr_info("%s\n", __func__); + + if (phy->powered == 1) + return 0; + + r = mei_cldev_enable(phy->cldev); + if (r < 0) { + pr_err("Could not enable device %d\n", r); + return r; + } + + r = mei_nfc_if_version(phy); + if (r < 0) { + pr_err("Could not enable device %d\n", r); + goto err; + } + + r = mei_nfc_connect(phy); + if (r < 0) { + pr_err("Could not connect to device %d\n", r); + goto err; + } + + r = mei_cldev_register_rx_cb(phy->cldev, nfc_mei_rx_cb); + if (r) { + pr_err("Event cb registration failed %d\n", r); + goto err; + } + + phy->powered = 1; + + return 0; + +err: + phy->powered = 0; + mei_cldev_disable(phy->cldev); + return r; +} + +static void nfc_mei_phy_disable(void *phy_id) +{ + struct nfc_mei_phy *phy = phy_id; + + pr_info("%s\n", __func__); + + mei_cldev_disable(phy->cldev); + + phy->powered = 0; +} + +struct nfc_phy_ops mei_phy_ops = { + .write = nfc_mei_phy_write, + .enable = nfc_mei_phy_enable, + .disable = nfc_mei_phy_disable, +}; +EXPORT_SYMBOL_GPL(mei_phy_ops); + +struct nfc_mei_phy *nfc_mei_phy_alloc(struct mei_cl_device *cldev) +{ + struct nfc_mei_phy *phy; + + phy = kzalloc(sizeof(struct nfc_mei_phy), GFP_KERNEL); + if (!phy) + return NULL; + + phy->cldev = cldev; + init_waitqueue_head(&phy->send_wq); + mei_cldev_set_drvdata(cldev, phy); + + return phy; +} +EXPORT_SYMBOL_GPL(nfc_mei_phy_alloc); + +void nfc_mei_phy_free(struct nfc_mei_phy *phy) +{ + mei_cldev_disable(phy->cldev); + kfree(phy); +} +EXPORT_SYMBOL_GPL(nfc_mei_phy_free); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("mei bus NFC device interface"); |