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 kfree_skb(skb);
155 }
156
157 return ret;
158 }
159
nfcmrvl_i2c_nci_update_config(struct nfcmrvl_private * priv,const void * param)160 static void nfcmrvl_i2c_nci_update_config(struct nfcmrvl_private *priv,
161 const void *param)
162 {
163 }
164
165 static struct nfcmrvl_if_ops i2c_ops = {
166 .nci_open = nfcmrvl_i2c_nci_open,
167 .nci_close = nfcmrvl_i2c_nci_close,
168 .nci_send = nfcmrvl_i2c_nci_send,
169 .nci_update_config = nfcmrvl_i2c_nci_update_config,
170 };
171
nfcmrvl_i2c_parse_dt(struct device_node * node,struct nfcmrvl_platform_data * pdata)172 static int nfcmrvl_i2c_parse_dt(struct device_node *node,
173 struct nfcmrvl_platform_data *pdata)
174 {
175 int ret;
176
177 ret = nfcmrvl_parse_dt(node, pdata);
178 if (ret < 0) {
179 pr_err("Failed to get generic entries\n");
180 return ret;
181 }
182
183 if (of_find_property(node, "i2c-int-falling", NULL))
184 pdata->irq_polarity = IRQF_TRIGGER_FALLING;
185 else
186 pdata->irq_polarity = IRQF_TRIGGER_RISING;
187
188 ret = irq_of_parse_and_map(node, 0);
189 if (ret < 0) {
190 pr_err("Unable to get irq, error: %d\n", ret);
191 return ret;
192 }
193 pdata->irq = ret;
194
195 return 0;
196 }
197
nfcmrvl_i2c_probe(struct i2c_client * client,const struct i2c_device_id * id)198 static int nfcmrvl_i2c_probe(struct i2c_client *client,
199 const struct i2c_device_id *id)
200 {
201 struct nfcmrvl_i2c_drv_data *drv_data;
202 struct nfcmrvl_platform_data *pdata;
203 struct nfcmrvl_platform_data config;
204 int ret;
205
206 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
207 nfc_err(&client->dev, "Need I2C_FUNC_I2C\n");
208 return -ENODEV;
209 }
210
211 drv_data = devm_kzalloc(&client->dev, sizeof(*drv_data), GFP_KERNEL);
212 if (!drv_data)
213 return -ENOMEM;
214
215 drv_data->i2c = client;
216 drv_data->dev = &client->dev;
217 drv_data->priv = NULL;
218
219 i2c_set_clientdata(client, drv_data);
220
221 pdata = client->dev.platform_data;
222
223 if (!pdata && client->dev.of_node)
224 if (nfcmrvl_i2c_parse_dt(client->dev.of_node, &config) == 0)
225 pdata = &config;
226
227 if (!pdata)
228 return -EINVAL;
229
230 /* Request the read IRQ */
231 ret = devm_request_threaded_irq(&drv_data->i2c->dev, pdata->irq,
232 NULL, nfcmrvl_i2c_int_irq_thread_fn,
233 pdata->irq_polarity | IRQF_ONESHOT,
234 "nfcmrvl_i2c_int", drv_data);
235 if (ret < 0) {
236 nfc_err(&drv_data->i2c->dev,
237 "Unable to register IRQ handler\n");
238 return ret;
239 }
240
241 drv_data->priv = nfcmrvl_nci_register_dev(NFCMRVL_PHY_I2C,
242 drv_data, &i2c_ops,
243 &drv_data->i2c->dev, pdata);
244
245 if (IS_ERR(drv_data->priv))
246 return PTR_ERR(drv_data->priv);
247
248 drv_data->priv->support_fw_dnld = true;
249
250 return 0;
251 }
252
nfcmrvl_i2c_remove(struct i2c_client * client)253 static int nfcmrvl_i2c_remove(struct i2c_client *client)
254 {
255 struct nfcmrvl_i2c_drv_data *drv_data = i2c_get_clientdata(client);
256
257 nfcmrvl_nci_unregister_dev(drv_data->priv);
258
259 return 0;
260 }
261
262
263 static const struct of_device_id of_nfcmrvl_i2c_match[] = {
264 { .compatible = "marvell,nfc-i2c", },
265 {},
266 };
267 MODULE_DEVICE_TABLE(of, of_nfcmrvl_i2c_match);
268
269 static const struct i2c_device_id nfcmrvl_i2c_id_table[] = {
270 { "nfcmrvl_i2c", 0 },
271 {}
272 };
273 MODULE_DEVICE_TABLE(i2c, nfcmrvl_i2c_id_table);
274
275 static struct i2c_driver nfcmrvl_i2c_driver = {
276 .probe = nfcmrvl_i2c_probe,
277 .id_table = nfcmrvl_i2c_id_table,
278 .remove = nfcmrvl_i2c_remove,
279 .driver = {
280 .name = "nfcmrvl_i2c",
281 .of_match_table = of_match_ptr(of_nfcmrvl_i2c_match),
282 },
283 };
284
285 module_i2c_driver(nfcmrvl_i2c_driver);
286
287 MODULE_AUTHOR("Marvell International Ltd.");
288 MODULE_DESCRIPTION("Marvell NFC-over-I2C driver");
289 MODULE_LICENSE("GPL v2");
290
