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authorH. Peter Anvin <hpa@linux.intel.com>2013-04-20 12:16:44 -0400
committerH. Peter Anvin <hpa@linux.intel.com>2013-04-20 12:16:44 -0400
commitf53f292eeaa234615c31a1306babe703fc4263f2 (patch)
tree707b0933a20f7dc05495e974243a23b5c9f8c918 /drivers/nfc/microread/mei.c
parent15b9c359f288b09003cb70f7ed204affc0c6614d (diff)
parenta9499fa7cd3fd4824a7202d00c766b269fa3bda6 (diff)
Merge remote-tracking branch 'efi/chainsaw' into x86/efi
Resolved Conflicts: drivers/firmware/efivars.c fs/efivarsfs/file.c Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'drivers/nfc/microread/mei.c')
-rw-r--r--drivers/nfc/microread/mei.c246
1 files changed, 246 insertions, 0 deletions
diff --git a/drivers/nfc/microread/mei.c b/drivers/nfc/microread/mei.c
new file mode 100644
index 000000000000..eef38cfd812e
--- /dev/null
+++ b/drivers/nfc/microread/mei.c
@@ -0,0 +1,246 @@
1/*
2 * HCI based Driver for Inside Secure microread NFC Chip
3 *
4 * Copyright (C) 2013 Intel Corporation. All rights reserved.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the
17 * Free Software Foundation, Inc.,
18 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19 */
20
21#include <linux/module.h>
22#include <linux/slab.h>
23#include <linux/interrupt.h>
24#include <linux/gpio.h>
25#include <linux/mei_bus.h>
26
27#include <linux/nfc.h>
28#include <net/nfc/hci.h>
29#include <net/nfc/llc.h>
30
31#include "microread.h"
32
33#define MICROREAD_DRIVER_NAME "microread"
34
35#define MICROREAD_UUID UUID_LE(0x0bb17a78, 0x2a8e, 0x4c50, 0x94, \
36 0xd4, 0x50, 0x26, 0x67, 0x23, 0x77, 0x5c)
37
38struct mei_nfc_hdr {
39 u8 cmd;
40 u8 status;
41 u16 req_id;
42 u32 reserved;
43 u16 data_size;
44} __attribute__((packed));
45
46#define MEI_NFC_HEADER_SIZE 10
47#define MEI_NFC_MAX_HCI_PAYLOAD 300
48#define MEI_NFC_MAX_READ (MEI_NFC_HEADER_SIZE + MEI_NFC_MAX_HCI_PAYLOAD)
49
50struct microread_mei_phy {
51 struct mei_device *mei_device;
52 struct nfc_hci_dev *hdev;
53
54 int powered;
55
56 int hard_fault; /*
57 * < 0 if hardware error occured (e.g. i2c err)
58 * and prevents normal operation.
59 */
60};
61
62#define MEI_DUMP_SKB_IN(info, skb) \
63do { \
64 pr_debug("%s:\n", info); \
65 print_hex_dump(KERN_DEBUG, "mei in : ", DUMP_PREFIX_OFFSET, \
66 16, 1, (skb)->data, (skb)->len, 0); \
67} while (0)
68
69#define MEI_DUMP_SKB_OUT(info, skb) \
70do { \
71 pr_debug("%s:\n", info); \
72 print_hex_dump(KERN_DEBUG, "mei out: ", DUMP_PREFIX_OFFSET, \
73 16, 1, (skb)->data, (skb)->len, 0); \
74} while (0)
75
76static int microread_mei_enable(void *phy_id)
77{
78 struct microread_mei_phy *phy = phy_id;
79
80 pr_info(DRIVER_DESC ": %s\n", __func__);
81
82 phy->powered = 1;
83
84 return 0;
85}
86
87static void microread_mei_disable(void *phy_id)
88{
89 struct microread_mei_phy *phy = phy_id;
90
91 pr_info(DRIVER_DESC ": %s\n", __func__);
92
93 phy->powered = 0;
94}
95
96/*
97 * Writing a frame must not return the number of written bytes.
98 * It must return either zero for success, or <0 for error.
99 * In addition, it must not alter the skb
100 */
101static int microread_mei_write(void *phy_id, struct sk_buff *skb)
102{
103 struct microread_mei_phy *phy = phy_id;
104 int r;
105
106 MEI_DUMP_SKB_OUT("mei frame sent", skb);
107
108 r = mei_send(phy->device, skb->data, skb->len);
109 if (r > 0)
110 r = 0;
111
112 return r;
113}
114
115static void microread_event_cb(struct mei_device *device, u32 events,
116 void *context)
117{
118 struct microread_mei_phy *phy = context;
119
120 if (phy->hard_fault != 0)
121 return;
122
123 if (events & BIT(MEI_EVENT_RX)) {
124 struct sk_buff *skb;
125 int reply_size;
126
127 skb = alloc_skb(MEI_NFC_MAX_READ, GFP_KERNEL);
128 if (!skb)
129 return;
130
131 reply_size = mei_recv(device, skb->data, MEI_NFC_MAX_READ);
132 if (reply_size < MEI_NFC_HEADER_SIZE) {
133 kfree(skb);
134 return;
135 }
136
137 skb_put(skb, reply_size);
138 skb_pull(skb, MEI_NFC_HEADER_SIZE);
139
140 MEI_DUMP_SKB_IN("mei frame read", skb);
141
142 nfc_hci_recv_frame(phy->hdev, skb);
143 }
144}
145
146static struct nfc_phy_ops mei_phy_ops = {
147 .write = microread_mei_write,
148 .enable = microread_mei_enable,
149 .disable = microread_mei_disable,
150};
151
152static int microread_mei_probe(struct mei_device *device,
153 const struct mei_id *id)
154{
155 struct microread_mei_phy *phy;
156 int r;
157
158 pr_info("Probing NFC microread\n");
159
160 phy = kzalloc(sizeof(struct microread_mei_phy), GFP_KERNEL);
161 if (!phy) {
162 pr_err("Cannot allocate memory for microread mei phy.\n");
163 return -ENOMEM;
164 }
165
166 phy->device = device;
167 mei_set_clientdata(device, phy);
168
169 r = mei_register_event_cb(device, microread_event_cb, phy);
170 if (r) {
171 pr_err(MICROREAD_DRIVER_NAME ": event cb registration failed\n");
172 goto err_out;
173 }
174
175 r = microread_probe(phy, &mei_phy_ops, LLC_NOP_NAME,
176 MEI_NFC_HEADER_SIZE, 0, MEI_NFC_MAX_HCI_PAYLOAD,
177 &phy->hdev);
178 if (r < 0)
179 goto err_out;
180
181 return 0;
182
183err_out:
184 kfree(phy);
185
186 return r;
187}
188
189static int microread_mei_remove(struct mei_device *device)
190{
191 struct microread_mei_phy *phy = mei_get_clientdata(device);
192
193 pr_info("Removing microread\n");
194
195 microread_remove(phy->hdev);
196
197 if (phy->powered)
198 microread_mei_disable(phy);
199
200 kfree(phy);
201
202 return 0;
203}
204
205static struct mei_id microread_mei_tbl[] = {
206 { MICROREAD_DRIVER_NAME, MICROREAD_UUID },
207
208 /* required last entry */
209 { }
210};
211
212MODULE_DEVICE_TABLE(mei, microread_mei_tbl);
213
214static struct mei_driver microread_driver = {
215 .id_table = microread_mei_tbl,
216 .name = MICROREAD_DRIVER_NAME,
217
218 .probe = microread_mei_probe,
219 .remove = microread_mei_remove,
220};
221
222static int microread_mei_init(void)
223{
224 int r;
225
226 pr_debug(DRIVER_DESC ": %s\n", __func__);
227
228 r = mei_driver_register(&microread_driver);
229 if (r) {
230 pr_err(MICROREAD_DRIVER_NAME ": driver registration failed\n");
231 return r;
232 }
233
234 return 0;
235}
236
237static void microread_mei_exit(void)
238{
239 mei_driver_unregister(&microread_driver);
240}
241
242module_init(microread_mei_init);
243module_exit(microread_mei_exit);
244
245MODULE_LICENSE("GPL");
246MODULE_DESCRIPTION(DRIVER_DESC);