1 /**
2 * Marvell NFC-over-I2C driver: I2C interface related functions
3 *
4 * Copyright (C) 2015, Marvell International Ltd.
5 *
6 * This software file (the "File") is distributed by Marvell International
7 * Ltd. under the terms of the GNU General Public License Version 2, June 1991
8 * (the "License"). You may use, redistribute and/or modify this File in
9 * accordance with the terms and conditions of the License, a copy of which
10 * is available on the worldwide web at
11 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
12 *
13 * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
14 * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
15 * ARE EXPRESSLY DISCLAIMED. The License provides additional details about
16 * this warranty disclaimer.
17 **/
18
19 #include <linux/module.h>
20 #include <linux/interrupt.h>
21 #include <linux/i2c.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/nfc.h>
24 #include <linux/gpio.h>
25 #include <linux/delay.h>
26 #include <linux/of_irq.h>
27 #include <linux/of_gpio.h>
28 #include <net/nfc/nci.h>
29 #include <net/nfc/nci_core.h>
30 #include "nfcmrvl.h"
31
32 struct nfcmrvl_i2c_drv_data {
33 unsigned long flags;
34 struct device *dev;
35 struct i2c_client *i2c;
36 struct nfcmrvl_private *priv;
37 };
38
nfcmrvl_i2c_read(struct nfcmrvl_i2c_drv_data * drv_data,struct sk_buff ** skb)39 static int nfcmrvl_i2c_read(struct nfcmrvl_i2c_drv_data *drv_data,
40 struct sk_buff **skb)
41 {
42 int ret;
43 struct nci_ctrl_hdr nci_hdr;
44
45 /* Read NCI header to know the payload size */
46 ret = i2c_master_recv(drv_data->i2c, (u8 *)&nci_hdr, NCI_CTRL_HDR_SIZE);
47 if (ret != NCI_CTRL_HDR_SIZE) {
48 nfc_err(&drv_data->i2c->dev, "cannot read NCI header\n");
49 return -EBADMSG;
50 }
51
52 if (nci_hdr.plen > NCI_MAX_PAYLOAD_SIZE) {
53 nfc_err(&drv_data->i2c->dev, "invalid packet payload size\n");
54 return -EBADMSG;
55 }
56
57 *skb = nci_skb_alloc(drv_data->priv->ndev,
58 nci_hdr.plen + NCI_CTRL_HDR_SIZE, GFP_KERNEL);
59 if (!*skb)
60 return -ENOMEM;
61
62 /* Copy NCI header into the SKB */
63 skb_put_data(*skb, &nci_hdr, NCI_CTRL_HDR_SIZE);
64
65 if (nci_hdr.plen) {
66 /* Read the NCI payload */
67 ret = i2c_master_recv(drv_data->i2c,
68 skb_put(*skb, nci_hdr.plen),
69 nci_hdr.plen);
70
71 if (ret != nci_hdr.plen) {
72 nfc_err(&drv_data->i2c->dev,
73 "Invalid frame payload length: %u (expected %u)\n",
74 ret, nci_hdr.plen);
75 kfree_skb(*skb);
76 return -EBADMSG;
77 }
78 }
79
80 return 0;
81 }
82
nfcmrvl_i2c_int_irq_thread_fn(int irq,void * drv_data_ptr)83 static irqreturn_t nfcmrvl_i2c_int_irq_thread_fn(int irq, void *drv_data_ptr)
84 {
85 struct nfcmrvl_i2c_drv_data *drv_data = drv_data_ptr;
86 struct sk_buff *skb = NULL;
87 int ret;
88
89 if (!drv_data->priv)
90 return IRQ_HANDLED;
91
92 if (test_bit(NFCMRVL_PHY_ERROR, &drv_data->priv->flags))
93 return IRQ_HANDLED;
94
95 ret = nfcmrvl_i2c_read(drv_data, &skb);
96
97 switch (ret) {
98 case -EREMOTEIO:
99 set_bit(NFCMRVL_PHY_ERROR, &drv_data->priv->flags);
100 break;
101 case -ENOMEM:
102 case -EBADMSG:
103 nfc_err(&drv_data->i2c->dev, "read failed %d\n", ret);
104 break;
105 default:
106 if (nfcmrvl_nci_recv_frame(drv_data->priv, skb) < 0)
107 nfc_err(&drv_data->i2c->dev, "corrupted RX packet\n");
108 break;
109 }
110 return IRQ_HANDLED;
111 }
112
nfcmrvl_i2c_nci_open(struct nfcmrvl_private * priv)113 static int nfcmrvl_i2c_nci_open(struct nfcmrvl_private *priv)
114 {
115 struct nfcmrvl_i2c_drv_data *drv_data = priv->drv_data;
116
117 if (!drv_data)
118 return -ENODEV;
119
120 return 0;
121 }
122
nfcmrvl_i2c_nci_close(struct nfcmrvl_private * priv)123 static int nfcmrvl_i2c_nci_close(struct nfcmrvl_private *priv)
124 {
125 return 0;
126 }
127
nfcmrvl_i2c_nci_send(struct nfcmrvl_private * priv,struct sk_buff * skb)128 static int nfcmrvl_i2c_nci_send(struct nfcmrvl_private *priv,
129 struct sk_buff *skb)
130 {
131 struct nfcmrvl_i2c_drv_data *drv_data = priv->drv_data;
132 int ret;
133
134 if (test_bit(NFCMRVL_PHY_ERROR, &priv->flags))
135 return -EREMOTEIO;
136
137 ret = i2c_master_send(drv_data->i2c, skb->data, skb->len);
138
139 /* Retry if chip was in standby */
140 if (ret == -EREMOTEIO) {
141 nfc_info(drv_data->dev, "chip may sleep, retry\n");
142 usleep_range(6000, 10000);
143 ret = i2c_master_send(drv_data->i2c, skb->data, skb->len);
144 }
145
146 if (ret >= 0) {
147 if (ret != skb->len) {
148 nfc_err(drv_data->dev,
149 "Invalid length sent: %u (expected %u)\n",
150 ret, skb->len);
151 ret = -EREMOTEIO;
152 } else
153 ret = 0;
154 }
155
156 if (ret) {
157 kfree_skb(skb);
158 return ret;
159 }
160
161 consume_skb(skb);
162 return 0;
163 }
164
nfcmrvl_i2c_nci_update_config(struct nfcmrvl_private * priv,const void * param)165 static void nfcmrvl_i2c_nci_update_config(struct nfcmrvl_private *priv,
166 const void *param)
167 {
168 }
169
170 static struct nfcmrvl_if_ops i2c_ops = {
171 .nci_open = nfcmrvl_i2c_nci_open,
172 .nci_close = nfcmrvl_i2c_nci_close,
173 .nci_send = nfcmrvl_i2c_nci_send,
174 .nci_update_config = nfcmrvl_i2c_nci_update_config,
175 };
176
nfcmrvl_i2c_parse_dt(struct device_node * node,struct nfcmrvl_platform_data * pdata)177 static int nfcmrvl_i2c_parse_dt(struct device_node *node,
178 struct nfcmrvl_platform_data *pdata)
179 {
180 int ret;
181
182 ret = nfcmrvl_parse_dt(node, pdata);
183 if (ret < 0) {
184 pr_err("Failed to get generic entries\n");
185 return ret;
186 }
187
188 if (of_find_property(node, "i2c-int-falling", NULL))
189 pdata->irq_polarity = IRQF_TRIGGER_FALLING;
190 else
191 pdata->irq_polarity = IRQF_TRIGGER_RISING;
192
193 ret = irq_of_parse_and_map(node, 0);
194 if (!ret) {
195 pr_err("Unable to get irq\n");
196 return -EINVAL;
197 }
198 pdata->irq = ret;
199
200 return 0;
201 }
202
nfcmrvl_i2c_probe(struct i2c_client * client,const struct i2c_device_id * id)203 static int nfcmrvl_i2c_probe(struct i2c_client *client,
204 const struct i2c_device_id *id)
205 {
206 struct nfcmrvl_i2c_drv_data *drv_data;
207 struct nfcmrvl_platform_data *pdata;
208 struct nfcmrvl_platform_data config;
209 int ret;
210
211 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
212 nfc_err(&client->dev, "Need I2C_FUNC_I2C\n");
213 return -ENODEV;
214 }
215
216 drv_data = devm_kzalloc(&client->dev, sizeof(*drv_data), GFP_KERNEL);
217 if (!drv_data)
218 return -ENOMEM;
219
220 drv_data->i2c = client;
221 drv_data->dev = &client->dev;
222 drv_data->priv = NULL;
223
224 i2c_set_clientdata(client, drv_data);
225
226 pdata = client->dev.platform_data;
227
228 if (!pdata && client->dev.of_node)
229 if (nfcmrvl_i2c_parse_dt(client->dev.of_node, &config) == 0)
230 pdata = &config;
231
232 if (!pdata)
233 return -EINVAL;
234
235 /* Request the read IRQ */
236 ret = devm_request_threaded_irq(&drv_data->i2c->dev, pdata->irq,
237 NULL, nfcmrvl_i2c_int_irq_thread_fn,
238 pdata->irq_polarity | IRQF_ONESHOT,
239 "nfcmrvl_i2c_int", drv_data);
240 if (ret < 0) {
241 nfc_err(&drv_data->i2c->dev,
242 "Unable to register IRQ handler\n");
243 return ret;
244 }
245
246 drv_data->priv = nfcmrvl_nci_register_dev(NFCMRVL_PHY_I2C,
247 drv_data, &i2c_ops,
248 &drv_data->i2c->dev, pdata);
249
250 if (IS_ERR(drv_data->priv))
251 return PTR_ERR(drv_data->priv);
252
253 drv_data->priv->support_fw_dnld = true;
254
255 return 0;
256 }
257
nfcmrvl_i2c_remove(struct i2c_client * client)258 static int nfcmrvl_i2c_remove(struct i2c_client *client)
259 {
260 struct nfcmrvl_i2c_drv_data *drv_data = i2c_get_clientdata(client);
261
262 nfcmrvl_nci_unregister_dev(drv_data->priv);
263
264 return 0;
265 }
266
267
268 static const struct of_device_id of_nfcmrvl_i2c_match[] = {
269 { .compatible = "marvell,nfc-i2c", },
270 {},
271 };
272 MODULE_DEVICE_TABLE(of, of_nfcmrvl_i2c_match);
273
274 static const struct i2c_device_id nfcmrvl_i2c_id_table[] = {
275 { "nfcmrvl_i2c", 0 },
276 {}
277 };
278 MODULE_DEVICE_TABLE(i2c, nfcmrvl_i2c_id_table);
279
280 static struct i2c_driver nfcmrvl_i2c_driver = {
281 .probe = nfcmrvl_i2c_probe,
282 .id_table = nfcmrvl_i2c_id_table,
283 .remove = nfcmrvl_i2c_remove,
284 .driver = {
285 .name = "nfcmrvl_i2c",
286 .of_match_table = of_match_ptr(of_nfcmrvl_i2c_match),
287 },
288 };
289
290 module_i2c_driver(nfcmrvl_i2c_driver);
291
292 MODULE_AUTHOR("Marvell International Ltd.");
293 MODULE_DESCRIPTION("Marvell NFC-over-I2C driver");
294 MODULE_LICENSE("GPL v2");
295