xref: /openbmc/linux/drivers/nfc/nfcmrvl/main.c (revision b85d4594)
1 /*
2  * Marvell NFC driver: major functions
3  *
4  * Copyright (C) 2014, 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/gpio.h>
21 #include <linux/delay.h>
22 #include <linux/of_gpio.h>
23 #include <linux/nfc.h>
24 #include <net/nfc/nci.h>
25 #include <net/nfc/nci_core.h>
26 #include "nfcmrvl.h"
27 
28 #define VERSION "1.0"
29 
30 static int nfcmrvl_nci_open(struct nci_dev *ndev)
31 {
32 	struct nfcmrvl_private *priv = nci_get_drvdata(ndev);
33 	int err;
34 
35 	if (test_and_set_bit(NFCMRVL_NCI_RUNNING, &priv->flags))
36 		return 0;
37 
38 	err = priv->if_ops->nci_open(priv);
39 
40 	if (err)
41 		clear_bit(NFCMRVL_NCI_RUNNING, &priv->flags);
42 
43 	return err;
44 }
45 
46 static int nfcmrvl_nci_close(struct nci_dev *ndev)
47 {
48 	struct nfcmrvl_private *priv = nci_get_drvdata(ndev);
49 
50 	if (!test_and_clear_bit(NFCMRVL_NCI_RUNNING, &priv->flags))
51 		return 0;
52 
53 	priv->if_ops->nci_close(priv);
54 
55 	return 0;
56 }
57 
58 static int nfcmrvl_nci_send(struct nci_dev *ndev, struct sk_buff *skb)
59 {
60 	struct nfcmrvl_private *priv = nci_get_drvdata(ndev);
61 
62 	nfc_info(priv->dev, "send entry, len %d\n", skb->len);
63 
64 	skb->dev = (void *)ndev;
65 
66 	if (!test_bit(NFCMRVL_NCI_RUNNING, &priv->flags))
67 		return -EBUSY;
68 
69 	if (priv->config.hci_muxed) {
70 		unsigned char *hdr;
71 		unsigned char len = skb->len;
72 
73 		hdr = (char *) skb_push(skb, NFCMRVL_HCI_EVENT_HEADER_SIZE);
74 		hdr[0] = NFCMRVL_HCI_COMMAND_CODE;
75 		hdr[1] = NFCMRVL_HCI_OGF;
76 		hdr[2] = NFCMRVL_HCI_OCF;
77 		hdr[3] = len;
78 	}
79 
80 	return priv->if_ops->nci_send(priv, skb);
81 }
82 
83 static int nfcmrvl_nci_setup(struct nci_dev *ndev)
84 {
85 	__u8 val = 1;
86 
87 	nci_set_config(ndev, NFCMRVL_PB_BAIL_OUT, 1, &val);
88 	return 0;
89 }
90 
91 static struct nci_ops nfcmrvl_nci_ops = {
92 	.open = nfcmrvl_nci_open,
93 	.close = nfcmrvl_nci_close,
94 	.send = nfcmrvl_nci_send,
95 	.setup = nfcmrvl_nci_setup,
96 };
97 
98 struct nfcmrvl_private *nfcmrvl_nci_register_dev(void *drv_data,
99 				struct nfcmrvl_if_ops *ops,
100 				struct device *dev,
101 				struct nfcmrvl_platform_data *pdata)
102 {
103 	struct nfcmrvl_private *priv;
104 	int rc;
105 	int headroom = 0;
106 	u32 protocols;
107 
108 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
109 	if (!priv)
110 		return ERR_PTR(-ENOMEM);
111 
112 	priv->drv_data = drv_data;
113 	priv->if_ops = ops;
114 	priv->dev = dev;
115 
116 	memcpy(&priv->config, pdata, sizeof(*pdata));
117 
118 	if (priv->config.reset_n_io) {
119 		rc = devm_gpio_request_one(dev,
120 					   priv->config.reset_n_io,
121 					   GPIOF_OUT_INIT_LOW,
122 					   "nfcmrvl_reset_n");
123 		if (rc < 0)
124 			nfc_err(dev, "failed to request reset_n io\n");
125 	}
126 
127 	if (priv->config.hci_muxed)
128 		headroom = NFCMRVL_HCI_EVENT_HEADER_SIZE;
129 
130 	protocols = NFC_PROTO_JEWEL_MASK
131 		| NFC_PROTO_MIFARE_MASK
132 		| NFC_PROTO_FELICA_MASK
133 		| NFC_PROTO_ISO14443_MASK
134 		| NFC_PROTO_ISO14443_B_MASK
135 		| NFC_PROTO_ISO15693_MASK
136 		| NFC_PROTO_NFC_DEP_MASK;
137 
138 	priv->ndev = nci_allocate_device(&nfcmrvl_nci_ops, protocols,
139 					 headroom, 0);
140 	if (!priv->ndev) {
141 		nfc_err(dev, "nci_allocate_device failed\n");
142 		rc = -ENOMEM;
143 		goto error;
144 	}
145 
146 	nci_set_drvdata(priv->ndev, priv);
147 
148 	nfcmrvl_chip_reset(priv);
149 
150 	rc = nci_register_device(priv->ndev);
151 	if (rc) {
152 		nfc_err(dev, "nci_register_device failed %d\n", rc);
153 		nci_free_device(priv->ndev);
154 		goto error;
155 	}
156 
157 	nfc_info(dev, "registered with nci successfully\n");
158 	return priv;
159 
160 error:
161 	kfree(priv);
162 	return ERR_PTR(rc);
163 }
164 EXPORT_SYMBOL_GPL(nfcmrvl_nci_register_dev);
165 
166 void nfcmrvl_nci_unregister_dev(struct nfcmrvl_private *priv)
167 {
168 	struct nci_dev *ndev = priv->ndev;
169 
170 	nci_unregister_device(ndev);
171 	nci_free_device(ndev);
172 	kfree(priv);
173 }
174 EXPORT_SYMBOL_GPL(nfcmrvl_nci_unregister_dev);
175 
176 int nfcmrvl_nci_recv_frame(struct nfcmrvl_private *priv, struct sk_buff *skb)
177 {
178 	if (priv->config.hci_muxed) {
179 		if (skb->data[0] == NFCMRVL_HCI_EVENT_CODE &&
180 		    skb->data[1] == NFCMRVL_HCI_NFC_EVENT_CODE) {
181 			/* Data packet, let's extract NCI payload */
182 			skb_pull(skb, NFCMRVL_HCI_EVENT_HEADER_SIZE);
183 		} else {
184 			/* Skip this packet */
185 			kfree_skb(skb);
186 			return 0;
187 		}
188 	}
189 
190 	if (test_bit(NFCMRVL_NCI_RUNNING, &priv->flags))
191 		nci_recv_frame(priv->ndev, skb);
192 	else {
193 		/* Drop this packet since nobody wants it */
194 		kfree_skb(skb);
195 		return 0;
196 	}
197 
198 	return 0;
199 }
200 EXPORT_SYMBOL_GPL(nfcmrvl_nci_recv_frame);
201 
202 void nfcmrvl_chip_reset(struct nfcmrvl_private *priv)
203 {
204 	/*
205 	 * This function does not take care if someone is using the device.
206 	 * To be improved.
207 	 */
208 
209 	if (priv->config.reset_n_io) {
210 		nfc_info(priv->dev, "reset the chip\n");
211 		gpio_set_value(priv->config.reset_n_io, 0);
212 		usleep_range(5000, 10000);
213 		gpio_set_value(priv->config.reset_n_io, 1);
214 	} else
215 		nfc_info(priv->dev, "no reset available on this interface\n");
216 }
217 
218 #ifdef CONFIG_OF
219 
220 int nfcmrvl_parse_dt(struct device_node *node,
221 		     struct nfcmrvl_platform_data *pdata)
222 {
223 	int reset_n_io;
224 
225 	reset_n_io = of_get_named_gpio(node, "reset-n-io", 0);
226 	if (reset_n_io < 0) {
227 		pr_info("no reset-n-io config\n");
228 		reset_n_io = 0;
229 	} else if (!gpio_is_valid(reset_n_io)) {
230 		pr_err("invalid reset-n-io GPIO\n");
231 		return reset_n_io;
232 	}
233 	pdata->reset_n_io = reset_n_io;
234 
235 	if (of_find_property(node, "hci-muxed", NULL))
236 		pdata->hci_muxed = 1;
237 	else
238 		pdata->hci_muxed = 0;
239 
240 	return 0;
241 }
242 
243 #else
244 
245 int nfcmrvl_parse_dt(struct device_node *node,
246 		     struct nfcmrvl_platform_data *pdata)
247 {
248 	return -ENODEV;
249 }
250 
251 #endif
252 EXPORT_SYMBOL_GPL(nfcmrvl_parse_dt);
253 
254 MODULE_AUTHOR("Marvell International Ltd.");
255 MODULE_DESCRIPTION("Marvell NFC driver ver " VERSION);
256 MODULE_VERSION(VERSION);
257 MODULE_LICENSE("GPL v2");
258