diff options
Diffstat (limited to 'drivers/nfc/mei_phy.c')
| -rw-r--r-- | drivers/nfc/mei_phy.c | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/drivers/nfc/mei_phy.c b/drivers/nfc/mei_phy.c new file mode 100644 index 00000000000..11c7cbdade6 --- /dev/null +++ b/drivers/nfc/mei_phy.c @@ -0,0 +1,173 @@ +/* + * 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"); |