1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Marvell NFC-over-UART driver
4 *
5 * Copyright (C) 2015, Marvell International Ltd.
6 */
7
8#include <linux/module.h>
9#include <linux/delay.h>
10#include <linux/of_gpio.h>
11#include <net/nfc/nci.h>
12#include <net/nfc/nci_core.h>
13#include "nfcmrvl.h"
14
15static unsigned int hci_muxed;
16static unsigned int flow_control;
17static unsigned int break_control;
18static int reset_n_io = -EINVAL;
19
20/*
21 * NFCMRVL NCI OPS
22 */
23
24static int nfcmrvl_uart_nci_open(struct nfcmrvl_private *priv)
25{
26 return 0;
27}
28
29static int nfcmrvl_uart_nci_close(struct nfcmrvl_private *priv)
30{
31 return 0;
32}
33
34static int nfcmrvl_uart_nci_send(struct nfcmrvl_private *priv,
35 struct sk_buff *skb)
36{
37 struct nci_uart *nu = priv->drv_data;
38
39 return nu->ops.send(nu, skb);
40}
41
42static void nfcmrvl_uart_nci_update_config(struct nfcmrvl_private *priv,
43 const void *param)
44{
45 struct nci_uart *nu = priv->drv_data;
46 const struct nfcmrvl_fw_uart_config *config = param;
47
48 nci_uart_set_config(nu, le32_to_cpu(config->baudrate),
49 flow_ctrl: config->flow_control);
50}
51
52static const struct nfcmrvl_if_ops uart_ops = {
53 .nci_open = nfcmrvl_uart_nci_open,
54 .nci_close = nfcmrvl_uart_nci_close,
55 .nci_send = nfcmrvl_uart_nci_send,
56 .nci_update_config = nfcmrvl_uart_nci_update_config
57};
58
59static int nfcmrvl_uart_parse_dt(struct device_node *node,
60 struct nfcmrvl_platform_data *pdata)
61{
62 struct device_node *matched_node;
63 int ret;
64
65 matched_node = of_get_compatible_child(parent: node, compatible: "marvell,nfc-uart");
66 if (!matched_node) {
67 matched_node = of_get_compatible_child(parent: node, compatible: "mrvl,nfc-uart");
68 if (!matched_node)
69 return -ENODEV;
70 }
71
72 ret = nfcmrvl_parse_dt(node: matched_node, pdata);
73 if (ret < 0) {
74 pr_err("Failed to get generic entries\n");
75 of_node_put(node: matched_node);
76 return ret;
77 }
78
79 pdata->flow_control = of_property_read_bool(np: matched_node, propname: "flow-control");
80 pdata->break_control = of_property_read_bool(np: matched_node, propname: "break-control");
81
82 of_node_put(node: matched_node);
83
84 return 0;
85}
86
87/*
88 * NCI UART OPS
89 */
90
91static int nfcmrvl_nci_uart_open(struct nci_uart *nu)
92{
93 struct nfcmrvl_private *priv;
94 struct nfcmrvl_platform_data config;
95 const struct nfcmrvl_platform_data *pdata = NULL;
96 struct device *dev = nu->tty->dev;
97
98 /*
99 * Platform data cannot be used here since usually it is already used
100 * by low level serial driver. We can try to retrieve serial device
101 * and check if DT entries were added.
102 */
103
104 if (dev && dev->parent && dev->parent->of_node)
105 if (nfcmrvl_uart_parse_dt(node: dev->parent->of_node, pdata: &config) == 0)
106 pdata = &config;
107
108 if (!pdata) {
109 pr_info("No platform data / DT -> fallback to module params\n");
110 config.hci_muxed = hci_muxed;
111 config.reset_n_io = reset_n_io;
112 config.flow_control = flow_control;
113 config.break_control = break_control;
114 pdata = &config;
115 }
116
117 priv = nfcmrvl_nci_register_dev(phy: NFCMRVL_PHY_UART, drv_data: nu, ops: &uart_ops,
118 dev, pdata);
119 if (IS_ERR(ptr: priv))
120 return PTR_ERR(ptr: priv);
121
122 priv->support_fw_dnld = true;
123
124 nu->drv_data = priv;
125 nu->ndev = priv->ndev;
126
127 return 0;
128}
129
130static void nfcmrvl_nci_uart_close(struct nci_uart *nu)
131{
132 nfcmrvl_nci_unregister_dev(priv: (struct nfcmrvl_private *)nu->drv_data);
133}
134
135static int nfcmrvl_nci_uart_recv(struct nci_uart *nu, struct sk_buff *skb)
136{
137 return nfcmrvl_nci_recv_frame(priv: (struct nfcmrvl_private *)nu->drv_data,
138 skb);
139}
140
141static void nfcmrvl_nci_uart_tx_start(struct nci_uart *nu)
142{
143 struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data;
144
145 if (priv->ndev->nfc_dev->fw_download_in_progress)
146 return;
147
148 /* Remove BREAK to wake up the NFCC */
149 if (priv->config.break_control && nu->tty->ops->break_ctl) {
150 nu->tty->ops->break_ctl(nu->tty, 0);
151 usleep_range(min: 3000, max: 5000);
152 }
153}
154
155static void nfcmrvl_nci_uart_tx_done(struct nci_uart *nu)
156{
157 struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data;
158
159 if (priv->ndev->nfc_dev->fw_download_in_progress)
160 return;
161
162 /*
163 * To ensure that if the NFCC goes in DEEP SLEEP sate we can wake him
164 * up. we set BREAK. Once we will be ready to send again we will remove
165 * it.
166 */
167 if (priv->config.break_control && nu->tty->ops->break_ctl) {
168 nu->tty->ops->break_ctl(nu->tty, -1);
169 usleep_range(min: 1000, max: 3000);
170 }
171}
172
173static struct nci_uart nfcmrvl_nci_uart = {
174 .owner = THIS_MODULE,
175 .name = "nfcmrvl_uart",
176 .driver = NCI_UART_DRIVER_MARVELL,
177 .ops = {
178 .open = nfcmrvl_nci_uart_open,
179 .close = nfcmrvl_nci_uart_close,
180 .recv = nfcmrvl_nci_uart_recv,
181 .tx_start = nfcmrvl_nci_uart_tx_start,
182 .tx_done = nfcmrvl_nci_uart_tx_done,
183 }
184};
185module_driver(nfcmrvl_nci_uart, nci_uart_register, nci_uart_unregister);
186
187MODULE_AUTHOR("Marvell International Ltd.");
188MODULE_DESCRIPTION("Marvell NFC-over-UART");
189MODULE_LICENSE("GPL v2");
190
191module_param(flow_control, uint, 0);
192MODULE_PARM_DESC(flow_control, "Tell if UART needs flow control at init.");
193
194module_param(break_control, uint, 0);
195MODULE_PARM_DESC(break_control, "Tell if UART driver must drive break signal.");
196
197module_param(hci_muxed, uint, 0);
198MODULE_PARM_DESC(hci_muxed, "Tell if transport is muxed in HCI one.");
199
200module_param(reset_n_io, int, 0);
201MODULE_PARM_DESC(reset_n_io, "GPIO that is wired to RESET_N signal.");
202

source code of linux/drivers/nfc/nfcmrvl/uart.c