summaryrefslogtreecommitdiff
path: root/drivers/nfc/nfcmrvl/i2c.c
blob: 7a44025bdaadbda6b304d2f7d8f764c5dd8defac (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
/**
 * Marvell NFC-over-I2C driver: I2C interface related functions
 *
 * Copyright (C) 2015, Marvell International Ltd.
 *
 * This software file (the "File") is distributed by Marvell International
 * Ltd. under the terms of the GNU General Public License Version 2, June 1991
 * (the "License").  You may use, redistribute and/or modify this File in
 * accordance with the terms and conditions of the License, a copy of which
 * is available on the worldwide web at
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
 *
 * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
 * ARE EXPRESSLY DISCLAIMED.  The License provides additional details about
 * this warranty disclaimer.
 **/

#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/i2c.h>
#include <linux/pm_runtime.h>
#include <linux/nfc.h>
#include <linux/gpio.h>
#include <linux/delay.h>
#include <linux/of_irq.h>
#include <linux/of_gpio.h>
#include <net/nfc/nci.h>
#include <net/nfc/nci_core.h>
#include "nfcmrvl.h"

struct nfcmrvl_i2c_drv_data {
	unsigned long flags;
	struct device *dev;
	struct i2c_client *i2c;
	struct nfcmrvl_private *priv;
};

static int nfcmrvl_i2c_read(struct nfcmrvl_i2c_drv_data *drv_data,
			    struct sk_buff **skb)
{
	int ret;
	struct nci_ctrl_hdr nci_hdr;

	/* Read NCI header to know the payload size */
	ret = i2c_master_recv(drv_data->i2c, (u8 *)&nci_hdr, NCI_CTRL_HDR_SIZE);
	if (ret != NCI_CTRL_HDR_SIZE) {
		nfc_err(&drv_data->i2c->dev, "cannot read NCI header\n");
		return -EBADMSG;
	}

	if (nci_hdr.plen > NCI_MAX_PAYLOAD_SIZE) {
		nfc_err(&drv_data->i2c->dev, "invalid packet payload size\n");
		return -EBADMSG;
	}

	*skb = nci_skb_alloc(drv_data->priv->ndev,
			     nci_hdr.plen + NCI_CTRL_HDR_SIZE, GFP_KERNEL);
	if (!*skb)
		return -ENOMEM;

	/* Copy NCI header into the SKB */
	memcpy(skb_put(*skb, NCI_CTRL_HDR_SIZE), &nci_hdr, NCI_CTRL_HDR_SIZE);

	if (nci_hdr.plen) {
		/* Read the NCI payload */
		ret = i2c_master_recv(drv_data->i2c,
				      skb_put(*skb, nci_hdr.plen),
				      nci_hdr.plen);

		if (ret != nci_hdr.plen) {
			nfc_err(&drv_data->i2c->dev,
				"Invalid frame payload length: %u (expected %u)\n",
				ret, nci_hdr.plen);
			kfree_skb(*skb);
			return -EBADMSG;
		}
	}

	return 0;
}

static irqreturn_t nfcmrvl_i2c_int_irq_thread_fn(int irq, void *drv_data_ptr)
{
	struct nfcmrvl_i2c_drv_data *drv_data = drv_data_ptr;
	struct sk_buff *skb = NULL;
	int ret;

	if (!drv_data->priv)
		return IRQ_HANDLED;

	if (test_bit(NFCMRVL_PHY_ERROR, &drv_data->priv->flags))
		return IRQ_HANDLED;

	ret = nfcmrvl_i2c_read(drv_data, &skb);

	switch (ret) {
	case -EREMOTEIO:
		set_bit(NFCMRVL_PHY_ERROR, &drv_data->priv->flags);
		break;
	case -ENOMEM:
	case -EBADMSG:
		nfc_err(&drv_data->i2c->dev, "read failed %d\n", ret);
		break;
	default:
		if (nfcmrvl_nci_recv_frame(drv_data->priv, skb) < 0)
			nfc_err(&drv_data->i2c->dev, "corrupted RX packet\n");
		break;
	}
	return IRQ_HANDLED;
}

static int nfcmrvl_i2c_nci_open(struct nfcmrvl_private *priv)
{
	struct nfcmrvl_i2c_drv_data *drv_data = priv->drv_data;

	if (!drv_data)
		return -ENODEV;

	return 0;
}

static int nfcmrvl_i2c_nci_close(struct nfcmrvl_private *priv)
{
	return 0;
}

static int nfcmrvl_i2c_nci_send(struct nfcmrvl_private *priv,
				struct sk_buff *skb)
{
	struct nfcmrvl_i2c_drv_data *drv_data = priv->drv_data;
	int ret;

	if (test_bit(NFCMRVL_PHY_ERROR, &priv->flags))
		return -EREMOTEIO;

	ret = i2c_master_send(drv_data->i2c, skb->data, skb->len);

	/* Retry if chip was in standby */
	if (ret == -EREMOTEIO) {
		nfc_info(drv_data->dev, "chip may sleep, retry\n");
		usleep_range(6000, 10000);
		ret = i2c_master_send(drv_data->i2c, skb->data, skb->len);
	}

	if (ret >= 0) {
		if (ret != skb->len) {
			nfc_err(drv_data->dev,
				"Invalid length sent: %u (expected %u)\n",
				ret, skb->len);
			ret = -EREMOTEIO;
		} else
			ret = 0;
		kfree_skb(skb);
	}

	return ret;
}

static void nfcmrvl_i2c_nci_update_config(struct nfcmrvl_private *priv,
					  const void *param)
{
}

static struct nfcmrvl_if_ops i2c_ops = {
	.nci_open = nfcmrvl_i2c_nci_open,
	.nci_close = nfcmrvl_i2c_nci_close,
	.nci_send = nfcmrvl_i2c_nci_send,
	.nci_update_config = nfcmrvl_i2c_nci_update_config,
};

static int nfcmrvl_i2c_parse_dt(struct device_node *node,
				struct nfcmrvl_platform_data *pdata)
{
	int ret;

	ret = nfcmrvl_parse_dt(node, pdata);
	if (ret < 0) {
		pr_err("Failed to get generic entries\n");
		return ret;
	}

	if (of_find_property(node, "i2c-int-falling", NULL))
		pdata->irq_polarity = IRQF_TRIGGER_FALLING;
	else
		pdata->irq_polarity = IRQF_TRIGGER_RISING;

	ret = irq_of_parse_and_map(node, 0);
	if (ret < 0) {
		pr_err("Unable to get irq, error: %d\n", ret);
		return ret;
	}
	pdata->irq = ret;

	return 0;
}

static int nfcmrvl_i2c_probe(struct i2c_client *client,
			     const struct i2c_device_id *id)
{
	struct nfcmrvl_i2c_drv_data *drv_data;
	struct nfcmrvl_platform_data *pdata;
	struct nfcmrvl_platform_data config;
	int ret;

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
		nfc_err(&client->dev, "Need I2C_FUNC_I2C\n");
		return -ENODEV;
	}

	drv_data = devm_kzalloc(&client->dev, sizeof(*drv_data), GFP_KERNEL);
	if (!drv_data)
		return -ENOMEM;

	drv_data->i2c = client;
	drv_data->dev = &client->dev;
	drv_data->priv = NULL;

	i2c_set_clientdata(client, drv_data);

	pdata = client->dev.platform_data;

	if (!pdata && client->dev.of_node)
		if (nfcmrvl_i2c_parse_dt(client->dev.of_node, &config) == 0)
			pdata = &config;

	if (!pdata)
		return -EINVAL;

	/* Request the read IRQ */
	ret = devm_request_threaded_irq(&drv_data->i2c->dev, pdata->irq,
					NULL, nfcmrvl_i2c_int_irq_thread_fn,
					pdata->irq_polarity | IRQF_ONESHOT,
					"nfcmrvl_i2c_int", drv_data);
	if (ret < 0) {
		nfc_err(&drv_data->i2c->dev,
			"Unable to register IRQ handler\n");
		return ret;
	}

	drv_data->priv = nfcmrvl_nci_register_dev(NFCMRVL_PHY_I2C,
						  drv_data, &i2c_ops,
						  &drv_data->i2c->dev, pdata);

	if (IS_ERR(drv_data->priv))
		return PTR_ERR(drv_data->priv);

	drv_data->priv->support_fw_dnld = true;

	return 0;
}

static int nfcmrvl_i2c_remove(struct i2c_client *client)
{
	struct nfcmrvl_i2c_drv_data *drv_data = i2c_get_clientdata(client);

	nfcmrvl_nci_unregister_dev(drv_data->priv);

	return 0;
}


static const struct of_device_id of_nfcmrvl_i2c_match[] = {
	{ .compatible = "mrvl,nfc-i2c", },
	{},
};
MODULE_DEVICE_TABLE(of, of_nfcmrvl_i2c_match);

static struct i2c_device_id nfcmrvl_i2c_id_table[] = {
	{ "nfcmrvl_i2c", 0 },
	{}
};
MODULE_DEVICE_TABLE(i2c, nfcmrvl_i2c_id_table);

static struct i2c_driver nfcmrvl_i2c_driver = {
	.probe = nfcmrvl_i2c_probe,
	.id_table = nfcmrvl_i2c_id_table,
	.remove = nfcmrvl_i2c_remove,
	.driver = {
		.name		= "nfcmrvl_i2c",
		.owner		= THIS_MODULE,
		.of_match_table	= of_match_ptr(of_nfcmrvl_i2c_match),
	},
};

module_i2c_driver(nfcmrvl_i2c_driver);

MODULE_AUTHOR("Marvell International Ltd.");
MODULE_DESCRIPTION("Marvell NFC-over-I2C driver");
MODULE_LICENSE("GPL v2");