/*
* 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/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");
