1/**
2 * Marvell NFC-over-UART driver
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/delay.h>
21#include <linux/of_gpio.h>
22#include <net/nfc/nci.h>
23#include <net/nfc/nci_core.h>
24#include "nfcmrvl.h"
25
26static unsigned int hci_muxed;
27static unsigned int flow_control;
28static unsigned int break_control;
29static unsigned int reset_n_io;
30
31/*
32** NFCMRVL NCI OPS
33*/
34
35static int nfcmrvl_uart_nci_open(struct nfcmrvl_private *priv)
36{
37 return 0;
38}
39
40static int nfcmrvl_uart_nci_close(struct nfcmrvl_private *priv)
41{
42 return 0;
43}
44
45static int nfcmrvl_uart_nci_send(struct nfcmrvl_private *priv,
46 struct sk_buff *skb)
47{
48 struct nci_uart *nu = priv->drv_data;
49
50 return nu->ops.send(nu, skb);
51}
52
53static void nfcmrvl_uart_nci_update_config(struct nfcmrvl_private *priv,
54 const void *param)
55{
56 struct nci_uart *nu = priv->drv_data;
57 const struct nfcmrvl_fw_uart_config *config = param;
58
59 nci_uart_set_config(nu, le32_to_cpu(config->baudrate),
60 config->flow_control);
61}
62
63static struct nfcmrvl_if_ops uart_ops = {
64 .nci_open = nfcmrvl_uart_nci_open,
65 .nci_close = nfcmrvl_uart_nci_close,
66 .nci_send = nfcmrvl_uart_nci_send,
67 .nci_update_config = nfcmrvl_uart_nci_update_config
68};
69
70static int nfcmrvl_uart_parse_dt(struct device_node *node,
71 struct nfcmrvl_platform_data *pdata)
72{
73 struct device_node *matched_node;
74 int ret;
75
76 matched_node = of_get_compatible_child(node, "marvell,nfc-uart");
77 if (!matched_node) {
78 matched_node = of_get_compatible_child(node, "mrvl,nfc-uart");
79 if (!matched_node)
80 return -ENODEV;
81 }
82
83 ret = nfcmrvl_parse_dt(matched_node, pdata);
84 if (ret < 0) {
85 pr_err("Failed to get generic entries\n");
86 of_node_put(matched_node);
87 return ret;
88 }
89
90 if (of_find_property(matched_node, "flow-control", NULL))
91 pdata->flow_control = 1;
92 else
93 pdata->flow_control = 0;
94
95 if (of_find_property(matched_node, "break-control", NULL))
96 pdata->break_control = 1;
97 else
98 pdata->break_control = 0;
99
100 of_node_put(matched_node);
101
102 return 0;
103}
104
105/*
106** NCI UART OPS
107*/
108
109static int nfcmrvl_nci_uart_open(struct nci_uart *nu)
110{
111 struct nfcmrvl_private *priv;
112 struct nfcmrvl_platform_data *pdata = NULL;
113 struct nfcmrvl_platform_data config;
114 struct device *dev = nu->tty->dev;
115
116 /*
117 * Platform data cannot be used here since usually it is already used
118 * by low level serial driver. We can try to retrieve serial device
119 * and check if DT entries were added.
120 */
121
122 if (dev && dev->parent && dev->parent->of_node)
123 if (nfcmrvl_uart_parse_dt(dev->parent->of_node, &config) == 0)
124 pdata = &config;
125
126 if (!pdata) {
127 pr_info("No platform data / DT -> fallback to module params\n");
128 config.hci_muxed = hci_muxed;
129 config.reset_n_io = reset_n_io;
130 config.flow_control = flow_control;
131 config.break_control = break_control;
132 pdata = &config;
133 }
134
135 priv = nfcmrvl_nci_register_dev(NFCMRVL_PHY_UART, nu, &uart_ops,
136 dev, pdata);
137 if (IS_ERR(priv))
138 return PTR_ERR(priv);
139
140 priv->support_fw_dnld = true;
141
142 nu->drv_data = priv;
143 nu->ndev = priv->ndev;
144
145 return 0;
146}
147
148static void nfcmrvl_nci_uart_close(struct nci_uart *nu)
149{
150 nfcmrvl_nci_unregister_dev((struct nfcmrvl_private *)nu->drv_data);
151}
152
153static int nfcmrvl_nci_uart_recv(struct nci_uart *nu, struct sk_buff *skb)
154{
155 return nfcmrvl_nci_recv_frame((struct nfcmrvl_private *)nu->drv_data,
156 skb);
157}
158
159static void nfcmrvl_nci_uart_tx_start(struct nci_uart *nu)
160{
161 struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data;
162
163 if (priv->ndev->nfc_dev->fw_download_in_progress)
164 return;
165
166 /* Remove BREAK to wake up the NFCC */
167 if (priv->config.break_control && nu->tty->ops->break_ctl) {
168 nu->tty->ops->break_ctl(nu->tty, 0);
169 usleep_range(3000, 5000);
170 }
171}
172
173static void nfcmrvl_nci_uart_tx_done(struct nci_uart *nu)
174{
175 struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data;
176
177 if (priv->ndev->nfc_dev->fw_download_in_progress)
178 return;
179
180 /*
181 ** To ensure that if the NFCC goes in DEEP SLEEP sate we can wake him
182 ** up. we set BREAK. Once we will be ready to send again we will remove
183 ** it.
184 */
185 if (priv->config.break_control && nu->tty->ops->break_ctl) {
186 nu->tty->ops->break_ctl(nu->tty, -1);
187 usleep_range(1000, 3000);
188 }
189}
190
191static struct nci_uart nfcmrvl_nci_uart = {
192 .owner = THIS_MODULE,
193 .name = "nfcmrvl_uart",
194 .driver = NCI_UART_DRIVER_MARVELL,
195 .ops = {
196 .open = nfcmrvl_nci_uart_open,
197 .close = nfcmrvl_nci_uart_close,
198 .recv = nfcmrvl_nci_uart_recv,
199 .tx_start = nfcmrvl_nci_uart_tx_start,
200 .tx_done = nfcmrvl_nci_uart_tx_done,
201 }
202};
203
204/*
205** Module init
206*/
207
208static int nfcmrvl_uart_init_module(void)
209{
210 return nci_uart_register(&nfcmrvl_nci_uart);
211}
212
213static void nfcmrvl_uart_exit_module(void)
214{
215 nci_uart_unregister(&nfcmrvl_nci_uart);
216}
217
218module_init(nfcmrvl_uart_init_module);
219module_exit(nfcmrvl_uart_exit_module);
220
221MODULE_AUTHOR("Marvell International Ltd.");
222MODULE_DESCRIPTION("Marvell NFC-over-UART");
223MODULE_LICENSE("GPL v2");
224
225module_param(flow_control, uint, 0);
226MODULE_PARM_DESC(flow_control, "Tell if UART needs flow control at init.");
227
228module_param(break_control, uint, 0);
229MODULE_PARM_DESC(break_control, "Tell if UART driver must drive break signal.");
230
231module_param(hci_muxed, uint, 0);
232MODULE_PARM_DESC(hci_muxed, "Tell if transport is muxed in HCI one.");
233
234module_param(reset_n_io, uint, 0);
235MODULE_PARM_DESC(reset_n_io, "GPIO that is wired to RESET_N signal.");
236