/*
* 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;
#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)
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_cl_enable_device(phy->device);
if (r < 0) {
pr_err("Could not enable device\n");
return r;
}
r = mei_cl_register_event_cb(phy->device, nfc_mei_event_cb, phy);
if (r) {
pr_err("Event cb registration failed\n");
mei_cl_disable_device(phy->device);
phy->powered = 0;
return r;
}
phy->powered = 1;
return 0;
}
EXPORT_SYMBOL_GPL(nfc_mei_phy_enable);
void nfc_mei_phy_disable(void *phy_id)
{
struct nfc_mei_phy *phy = phy_id;
pr_info("%s\n", __func__);
mei_cl_disable_device(phy->device);
phy->powered = 0;
}
EXPORT_SYMBOL_GPL(nfc_mei_phy_disable);
/*
* 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_cl_send(phy->device, skb->data, skb->len);
if (r > 0)
r = 0;
return r;
}
void nfc_mei_event_cb(struct mei_cl_device *device, u32 events, void *context)
{
struct nfc_mei_phy *phy = context;
if (phy->hard_fault != 0)
return;
if (events & BIT(MEI_CL_EVENT_RX)) {
struct sk_buff *skb;
int reply_size;
skb = alloc_skb(MEI_NFC_MAX_READ, GFP_KERNEL);
if (!skb)
return;
reply_size = mei_cl_recv(device, 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);
}
}
EXPORT_SYMBOL_GPL(nfc_mei_event_cb);
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 *device)
{
struct nfc_mei_phy *phy;
phy = kzalloc(sizeof(struct nfc_mei_phy), GFP_KERNEL);
if (!phy)
return NULL;
phy->device = device;
mei_cl_set_drvdata(device, phy);
return phy;
}
EXPORT_SYMBOL_GPL(nfc_mei_phy_alloc);
void nfc_mei_phy_free(struct nfc_mei_phy *phy)
{
kfree(phy);
}
EXPORT_SYMBOL_GPL(nfc_mei_phy_free);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("mei bus NFC device interface");
