linux-stable/drivers/nfc/nxp-nci/core.c
Krzysztof Kozlowski b9c28286d8 nfc: constify nci_ops
The struct nci_ops is modified by NFC core in only one case:
nci_allocate_device() receives too many proprietary commands (prop_ops)
to configure.  This is a build time known constrain, so a graceful
handling of such case is not necessary.

Instead, fail the nci_allocate_device() and add BUILD_BUG_ON() to places
which set these.

This allows to constify the struct nci_ops (consisting of function
pointers) for correctness and safety.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-25 09:21:20 +01:00

161 lines
3.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Generic driver for NXP NCI NFC chips
*
* Copyright (C) 2014 NXP Semiconductors All rights reserved.
*
* Authors: Clément Perrochaud <clement.perrochaud@nxp.com>
*
* Derived from PN544 device driver:
* Copyright (C) 2012 Intel Corporation. All rights reserved.
*/
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/nfc.h>
#include <net/nfc/nci_core.h>
#include "nxp-nci.h"
#define NXP_NCI_HDR_LEN 4
#define NXP_NCI_NFC_PROTOCOLS (NFC_PROTO_JEWEL_MASK | \
NFC_PROTO_MIFARE_MASK | \
NFC_PROTO_FELICA_MASK | \
NFC_PROTO_ISO14443_MASK | \
NFC_PROTO_ISO14443_B_MASK | \
NFC_PROTO_NFC_DEP_MASK)
static int nxp_nci_open(struct nci_dev *ndev)
{
struct nxp_nci_info *info = nci_get_drvdata(ndev);
int r = 0;
mutex_lock(&info->info_lock);
if (info->mode != NXP_NCI_MODE_COLD) {
r = -EBUSY;
goto open_exit;
}
if (info->phy_ops->set_mode)
r = info->phy_ops->set_mode(info->phy_id, NXP_NCI_MODE_NCI);
info->mode = NXP_NCI_MODE_NCI;
open_exit:
mutex_unlock(&info->info_lock);
return r;
}
static int nxp_nci_close(struct nci_dev *ndev)
{
struct nxp_nci_info *info = nci_get_drvdata(ndev);
int r = 0;
mutex_lock(&info->info_lock);
if (info->phy_ops->set_mode)
r = info->phy_ops->set_mode(info->phy_id, NXP_NCI_MODE_COLD);
info->mode = NXP_NCI_MODE_COLD;
mutex_unlock(&info->info_lock);
return r;
}
static int nxp_nci_send(struct nci_dev *ndev, struct sk_buff *skb)
{
struct nxp_nci_info *info = nci_get_drvdata(ndev);
int r;
if (!info->phy_ops->write)
return -EOPNOTSUPP;
if (info->mode != NXP_NCI_MODE_NCI)
return -EINVAL;
r = info->phy_ops->write(info->phy_id, skb);
if (r < 0)
kfree_skb(skb);
return r;
}
static const struct nci_ops nxp_nci_ops = {
.open = nxp_nci_open,
.close = nxp_nci_close,
.send = nxp_nci_send,
.fw_download = nxp_nci_fw_download,
};
int nxp_nci_probe(void *phy_id, struct device *pdev,
const struct nxp_nci_phy_ops *phy_ops,
unsigned int max_payload,
struct nci_dev **ndev)
{
struct nxp_nci_info *info;
int r;
info = devm_kzalloc(pdev, sizeof(struct nxp_nci_info), GFP_KERNEL);
if (!info)
return -ENOMEM;
info->phy_id = phy_id;
info->pdev = pdev;
info->phy_ops = phy_ops;
info->max_payload = max_payload;
INIT_WORK(&info->fw_info.work, nxp_nci_fw_work);
init_completion(&info->fw_info.cmd_completion);
mutex_init(&info->info_lock);
if (info->phy_ops->set_mode) {
r = info->phy_ops->set_mode(info->phy_id, NXP_NCI_MODE_COLD);
if (r < 0)
return r;
}
info->mode = NXP_NCI_MODE_COLD;
info->ndev = nci_allocate_device(&nxp_nci_ops, NXP_NCI_NFC_PROTOCOLS,
NXP_NCI_HDR_LEN, 0);
if (!info->ndev)
return -ENOMEM;
nci_set_parent_dev(info->ndev, pdev);
nci_set_drvdata(info->ndev, info);
r = nci_register_device(info->ndev);
if (r < 0) {
nci_free_device(info->ndev);
return r;
}
*ndev = info->ndev;
return r;
}
EXPORT_SYMBOL(nxp_nci_probe);
void nxp_nci_remove(struct nci_dev *ndev)
{
struct nxp_nci_info *info = nci_get_drvdata(ndev);
if (info->mode == NXP_NCI_MODE_FW)
nxp_nci_fw_work_complete(info, -ESHUTDOWN);
cancel_work_sync(&info->fw_info.work);
mutex_lock(&info->info_lock);
if (info->phy_ops->set_mode)
info->phy_ops->set_mode(info->phy_id, NXP_NCI_MODE_COLD);
nci_unregister_device(ndev);
nci_free_device(ndev);
mutex_unlock(&info->info_lock);
}
EXPORT_SYMBOL(nxp_nci_remove);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("NXP NCI NFC driver");
MODULE_AUTHOR("Clément Perrochaud <clement.perrochaud@nxp.com>");