summaryrefslogtreecommitdiffstats
path: root/drivers/nfc/nfcmrvl/uart.c
blob: f3d041c4f249e05dced87bd76786bc8a612fd915 (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
/**
 * Marvell NFC-over-UART driver
 *
 * 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/delay.h>
#include <linux/of_gpio.h>
#include <net/nfc/nci.h>
#include <net/nfc/nci_core.h>
#include "nfcmrvl.h"

static unsigned int hci_muxed;
static unsigned int flow_control;
static unsigned int break_control;
static unsigned int reset_n_io;

/*
** NFCMRVL NCI OPS
*/

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

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

static int nfcmrvl_uart_nci_send(struct nfcmrvl_private *priv,
				 struct sk_buff *skb)
{
	struct nci_uart *nu = priv->drv_data;

	return nu->ops.send(nu, skb);
}

static void nfcmrvl_uart_nci_update_config(struct nfcmrvl_private *priv,
					   const void *param)
{
	struct nci_uart *nu = priv->drv_data;
	const struct nfcmrvl_fw_uart_config *config = param;

	nci_uart_set_config(nu, le32_to_cpu(config->baudrate),
			    config->flow_control);
}

static struct nfcmrvl_if_ops uart_ops = {
	.nci_open = nfcmrvl_uart_nci_open,
	.nci_close = nfcmrvl_uart_nci_close,
	.nci_send = nfcmrvl_uart_nci_send,
	.nci_update_config = nfcmrvl_uart_nci_update_config
};

#ifdef CONFIG_OF

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

	matched_node = of_find_compatible_node(node, NULL, "marvell,nfc-uart");
	if (!matched_node) {
		matched_node = of_find_compatible_node(node, NULL,
						       "mrvl,nfc-uart");
		if (!matched_node)
			return -ENODEV;
	}

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

	if (of_find_property(matched_node, "flow-control", NULL))
		pdata->flow_control = 1;
	else
		pdata->flow_control = 0;

	if (of_find_property(matched_node, "break-control", NULL))
		pdata->break_control = 1;
	else
		pdata->break_control = 0;

	return 0;
}

#else

static int nfcmrvl_uart_parse_dt(struct device_node *node,
				 struct nfcmrvl_platform_data *pdata)
{
	return -ENODEV;
}

#endif

/*
** NCI UART OPS
*/

static int nfcmrvl_nci_uart_open(struct nci_uart *nu)
{
	struct nfcmrvl_private *priv;
	struct nfcmrvl_platform_data *pdata = NULL;
	struct nfcmrvl_platform_data config;

	/*
	 * Platform data cannot be used here since usually it is already used
	 * by low level serial driver. We can try to retrieve serial device
	 * and check if DT entries were added.
	 */

	if (nu->tty->dev->parent && nu->tty->dev->parent->of_node)
		if (nfcmrvl_uart_parse_dt(nu->tty->dev->parent->of_node,
					  &config) == 0)
			pdata = &config;

	if (!pdata) {
		pr_info("No platform data / DT -> fallback to module params\n");
		config.hci_muxed = hci_muxed;
		config.reset_n_io = reset_n_io;
		config.flow_control = flow_control;
		config.break_control = break_control;
		pdata = &config;
	}

	priv = nfcmrvl_nci_register_dev(NFCMRVL_PHY_UART, nu, &uart_ops,
					nu->tty->dev, pdata);
	if (IS_ERR(priv))
		return PTR_ERR(priv);

	priv->support_fw_dnld = true;

	nu->drv_data = priv;
	nu->ndev = priv->ndev;

	/* Set BREAK */
	if (priv->config.break_control && nu->tty->ops->break_ctl)
		nu->tty->ops->break_ctl(nu->tty, -1);

	return 0;
}

static void nfcmrvl_nci_uart_close(struct nci_uart *nu)
{
	nfcmrvl_nci_unregister_dev((struct nfcmrvl_private *)nu->drv_data);
}

static int nfcmrvl_nci_uart_recv(struct nci_uart *nu, struct sk_buff *skb)
{
	return nfcmrvl_nci_recv_frame((struct nfcmrvl_private *)nu->drv_data,
				      skb);
}

static void nfcmrvl_nci_uart_tx_start(struct nci_uart *nu)
{
	struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data;

	/* Remove BREAK to wake up the NFCC */
	if (priv->config.break_control && nu->tty->ops->break_ctl) {
		nu->tty->ops->break_ctl(nu->tty, 0);
		usleep_range(3000, 5000);
	}
}

static void nfcmrvl_nci_uart_tx_done(struct nci_uart *nu)
{
	struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data;

	/*
	** To ensure that if the NFCC goes in DEEP SLEEP sate we can wake him
	** up. we set BREAK. Once we will be ready to send again we will remove
	** it.
	*/
	if (priv->config.break_control && nu->tty->ops->break_ctl)
		nu->tty->ops->break_ctl(nu->tty, -1);
}

static struct nci_uart nfcmrvl_nci_uart = {
	.owner  = THIS_MODULE,
	.name   = "nfcmrvl_uart",
	.driver = NCI_UART_DRIVER_MARVELL,
	.ops	= {
		.open		= nfcmrvl_nci_uart_open,
		.close		= nfcmrvl_nci_uart_close,
		.recv		= nfcmrvl_nci_uart_recv,
		.tx_start	= nfcmrvl_nci_uart_tx_start,
		.tx_done	= nfcmrvl_nci_uart_tx_done,
	}
};

/*
** Module init
*/

static int nfcmrvl_uart_init_module(void)
{
	return nci_uart_register(&nfcmrvl_nci_uart);
}

static void nfcmrvl_uart_exit_module(void)
{
	nci_uart_unregister(&nfcmrvl_nci_uart);
}

module_init(nfcmrvl_uart_init_module);
module_exit(nfcmrvl_uart_exit_module);

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

module_param(flow_control, uint, 0);
MODULE_PARM_DESC(flow_control, "Tell if UART needs flow control at init.");

module_param(break_control, uint, 0);
MODULE_PARM_DESC(break_control, "Tell if UART driver must drive break signal.");

module_param(hci_muxed, uint, 0);
MODULE_PARM_DESC(hci_muxed, "Tell if transport is muxed in HCI one.");

module_param(reset_n_io, uint, 0);
MODULE_PARM_DESC(reset_n_io, "GPIO that is wired to RESET_N signal.");