// SPDX-License-Identifier: GPL-2.0 /* * Copyright (c) 2013, Intel Corporation. * * MEI Library for mei bus nfc device access */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/module.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");