1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* |
3 | * UART Link Layer for S3FWRN82 NCI based Driver |
4 | * |
5 | * Copyright (C) 2015 Samsung Electronics |
6 | * Robert Baldyga <r.baldyga@samsung.com> |
7 | * Copyright (C) 2020 Samsung Electronics |
8 | * Bongsu Jeon <bongsu.jeon@samsung.com> |
9 | */ |
10 | |
11 | #include <linux/device.h> |
12 | #include <linux/kernel.h> |
13 | #include <linux/module.h> |
14 | #include <linux/nfc.h> |
15 | #include <linux/netdevice.h> |
16 | #include <linux/of.h> |
17 | #include <linux/serdev.h> |
18 | #include <linux/gpio.h> |
19 | #include <linux/of_gpio.h> |
20 | |
21 | #include "phy_common.h" |
22 | |
23 | #define 3 |
24 | #define S3FWRN82_NCI_IDX 2 |
25 | #define NCI_SKB_BUFF_LEN 258 |
26 | |
27 | struct s3fwrn82_uart_phy { |
28 | struct phy_common common; |
29 | struct serdev_device *ser_dev; |
30 | struct sk_buff *recv_skb; |
31 | }; |
32 | |
33 | static int s3fwrn82_uart_write(void *phy_id, struct sk_buff *out) |
34 | { |
35 | struct s3fwrn82_uart_phy *phy = phy_id; |
36 | int err; |
37 | |
38 | err = serdev_device_write(phy->ser_dev, |
39 | out->data, out->len, |
40 | MAX_SCHEDULE_TIMEOUT); |
41 | if (err < 0) |
42 | return err; |
43 | |
44 | return 0; |
45 | } |
46 | |
47 | static const struct s3fwrn5_phy_ops uart_phy_ops = { |
48 | .set_wake = s3fwrn5_phy_set_wake, |
49 | .set_mode = s3fwrn5_phy_set_mode, |
50 | .get_mode = s3fwrn5_phy_get_mode, |
51 | .write = s3fwrn82_uart_write, |
52 | }; |
53 | |
54 | static size_t s3fwrn82_uart_read(struct serdev_device *serdev, |
55 | const u8 *data, size_t count) |
56 | { |
57 | struct s3fwrn82_uart_phy *phy = serdev_device_get_drvdata(serdev); |
58 | size_t i; |
59 | |
60 | for (i = 0; i < count; i++) { |
61 | skb_put_u8(skb: phy->recv_skb, val: *data++); |
62 | |
63 | if (phy->recv_skb->len < S3FWRN82_NCI_HEADER) |
64 | continue; |
65 | |
66 | if ((phy->recv_skb->len - S3FWRN82_NCI_HEADER) |
67 | < phy->recv_skb->data[S3FWRN82_NCI_IDX]) |
68 | continue; |
69 | |
70 | s3fwrn5_recv_frame(ndev: phy->common.ndev, skb: phy->recv_skb, |
71 | mode: phy->common.mode); |
72 | phy->recv_skb = alloc_skb(NCI_SKB_BUFF_LEN, GFP_KERNEL); |
73 | if (!phy->recv_skb) |
74 | return 0; |
75 | } |
76 | |
77 | return i; |
78 | } |
79 | |
80 | static const struct serdev_device_ops s3fwrn82_serdev_ops = { |
81 | .receive_buf = s3fwrn82_uart_read, |
82 | .write_wakeup = serdev_device_write_wakeup, |
83 | }; |
84 | |
85 | static const struct of_device_id s3fwrn82_uart_of_match[] = { |
86 | { .compatible = "samsung,s3fwrn82" , }, |
87 | {}, |
88 | }; |
89 | MODULE_DEVICE_TABLE(of, s3fwrn82_uart_of_match); |
90 | |
91 | static int s3fwrn82_uart_parse_dt(struct serdev_device *serdev) |
92 | { |
93 | struct s3fwrn82_uart_phy *phy = serdev_device_get_drvdata(serdev); |
94 | struct device_node *np = serdev->dev.of_node; |
95 | |
96 | if (!np) |
97 | return -ENODEV; |
98 | |
99 | phy->common.gpio_en = of_get_named_gpio(np, list_name: "en-gpios" , index: 0); |
100 | if (!gpio_is_valid(number: phy->common.gpio_en)) |
101 | return -ENODEV; |
102 | |
103 | phy->common.gpio_fw_wake = of_get_named_gpio(np, list_name: "wake-gpios" , index: 0); |
104 | if (!gpio_is_valid(number: phy->common.gpio_fw_wake)) |
105 | return -ENODEV; |
106 | |
107 | return 0; |
108 | } |
109 | |
110 | static int s3fwrn82_uart_probe(struct serdev_device *serdev) |
111 | { |
112 | struct s3fwrn82_uart_phy *phy; |
113 | int ret = -ENOMEM; |
114 | |
115 | phy = devm_kzalloc(dev: &serdev->dev, size: sizeof(*phy), GFP_KERNEL); |
116 | if (!phy) |
117 | goto err_exit; |
118 | |
119 | phy->recv_skb = alloc_skb(NCI_SKB_BUFF_LEN, GFP_KERNEL); |
120 | if (!phy->recv_skb) |
121 | goto err_exit; |
122 | |
123 | mutex_init(&phy->common.mutex); |
124 | phy->common.mode = S3FWRN5_MODE_COLD; |
125 | |
126 | phy->ser_dev = serdev; |
127 | serdev_device_set_drvdata(serdev, data: phy); |
128 | serdev_device_set_client_ops(serdev, ops: &s3fwrn82_serdev_ops); |
129 | ret = serdev_device_open(serdev); |
130 | if (ret) { |
131 | dev_err(&serdev->dev, "Unable to open device\n" ); |
132 | goto err_skb; |
133 | } |
134 | |
135 | ret = serdev_device_set_baudrate(serdev, 115200); |
136 | if (ret != 115200) { |
137 | ret = -EINVAL; |
138 | goto err_serdev; |
139 | } |
140 | |
141 | serdev_device_set_flow_control(serdev, false); |
142 | |
143 | ret = s3fwrn82_uart_parse_dt(serdev); |
144 | if (ret < 0) |
145 | goto err_serdev; |
146 | |
147 | ret = devm_gpio_request_one(dev: &phy->ser_dev->dev, gpio: phy->common.gpio_en, |
148 | GPIOF_OUT_INIT_HIGH, label: "s3fwrn82_en" ); |
149 | if (ret < 0) |
150 | goto err_serdev; |
151 | |
152 | ret = devm_gpio_request_one(dev: &phy->ser_dev->dev, |
153 | gpio: phy->common.gpio_fw_wake, |
154 | GPIOF_OUT_INIT_LOW, label: "s3fwrn82_fw_wake" ); |
155 | if (ret < 0) |
156 | goto err_serdev; |
157 | |
158 | ret = s3fwrn5_probe(ndev: &phy->common.ndev, phy_id: phy, pdev: &phy->ser_dev->dev, |
159 | phy_ops: &uart_phy_ops); |
160 | if (ret < 0) |
161 | goto err_serdev; |
162 | |
163 | return ret; |
164 | |
165 | err_serdev: |
166 | serdev_device_close(serdev); |
167 | err_skb: |
168 | kfree_skb(skb: phy->recv_skb); |
169 | err_exit: |
170 | return ret; |
171 | } |
172 | |
173 | static void s3fwrn82_uart_remove(struct serdev_device *serdev) |
174 | { |
175 | struct s3fwrn82_uart_phy *phy = serdev_device_get_drvdata(serdev); |
176 | |
177 | s3fwrn5_remove(ndev: phy->common.ndev); |
178 | serdev_device_close(serdev); |
179 | kfree_skb(skb: phy->recv_skb); |
180 | } |
181 | |
182 | static struct serdev_device_driver s3fwrn82_uart_driver = { |
183 | .probe = s3fwrn82_uart_probe, |
184 | .remove = s3fwrn82_uart_remove, |
185 | .driver = { |
186 | .name = "s3fwrn82_uart" , |
187 | .of_match_table = s3fwrn82_uart_of_match, |
188 | }, |
189 | }; |
190 | |
191 | module_serdev_device_driver(s3fwrn82_uart_driver); |
192 | |
193 | MODULE_LICENSE("GPL" ); |
194 | MODULE_DESCRIPTION("UART driver for Samsung NFC" ); |
195 | MODULE_AUTHOR("Bongsu Jeon <bongsu.jeon@samsung.com>" ); |
196 | |