1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * I2C Link Layer for Samsung S3FWRN5 NCI based Driver
5 * Copyright (C) 2015 Samsung Electrnoics
6 * Robert Baldyga <r.baldyga@samsung.com>
10 #include <linux/gpio.h>
11 #include <linux/delay.h>
12 #include <linux/of_gpio.h>
13 #include <linux/of_irq.h>
14 #include <linux/module.h>
16 #include <net/nfc/nfc.h>
20 #define S3FWRN5_I2C_DRIVER_NAME "s3fwrn5_i2c"
22 #define S3FWRN5_I2C_MAX_PAYLOAD 32
23 #define S3FWRN5_EN_WAIT_TIME 150
25 struct s3fwrn5_i2c_phy {
26 struct i2c_client *i2c_dev;
34 enum s3fwrn5_mode mode;
35 unsigned int irq_skip:1;
38 static void s3fwrn5_i2c_set_wake(void *phy_id, bool wake)
40 struct s3fwrn5_i2c_phy *phy = phy_id;
42 mutex_lock(&phy->mutex);
43 gpio_set_value(phy->gpio_fw_wake, wake);
44 msleep(S3FWRN5_EN_WAIT_TIME/2);
45 mutex_unlock(&phy->mutex);
48 static void s3fwrn5_i2c_set_mode(void *phy_id, enum s3fwrn5_mode mode)
50 struct s3fwrn5_i2c_phy *phy = phy_id;
52 mutex_lock(&phy->mutex);
54 if (phy->mode == mode)
59 gpio_set_value(phy->gpio_en, 1);
60 gpio_set_value(phy->gpio_fw_wake, 0);
61 if (mode == S3FWRN5_MODE_FW)
62 gpio_set_value(phy->gpio_fw_wake, 1);
64 if (mode != S3FWRN5_MODE_COLD) {
65 msleep(S3FWRN5_EN_WAIT_TIME);
66 gpio_set_value(phy->gpio_en, 0);
67 msleep(S3FWRN5_EN_WAIT_TIME/2);
73 mutex_unlock(&phy->mutex);
76 static enum s3fwrn5_mode s3fwrn5_i2c_get_mode(void *phy_id)
78 struct s3fwrn5_i2c_phy *phy = phy_id;
79 enum s3fwrn5_mode mode;
81 mutex_lock(&phy->mutex);
85 mutex_unlock(&phy->mutex);
90 static int s3fwrn5_i2c_write(void *phy_id, struct sk_buff *skb)
92 struct s3fwrn5_i2c_phy *phy = phy_id;
95 mutex_lock(&phy->mutex);
97 phy->irq_skip = false;
99 ret = i2c_master_send(phy->i2c_dev, skb->data, skb->len);
100 if (ret == -EREMOTEIO) {
101 /* Retry, chip was in standby */
102 usleep_range(110000, 120000);
103 ret = i2c_master_send(phy->i2c_dev, skb->data, skb->len);
106 mutex_unlock(&phy->mutex);
117 static const struct s3fwrn5_phy_ops i2c_phy_ops = {
118 .set_wake = s3fwrn5_i2c_set_wake,
119 .set_mode = s3fwrn5_i2c_set_mode,
120 .get_mode = s3fwrn5_i2c_get_mode,
121 .write = s3fwrn5_i2c_write,
124 static int s3fwrn5_i2c_read(struct s3fwrn5_i2c_phy *phy)
132 hdr_size = (phy->mode == S3FWRN5_MODE_NCI) ?
133 NCI_CTRL_HDR_SIZE : S3FWRN5_FW_HDR_SIZE;
134 ret = i2c_master_recv(phy->i2c_dev, hdr, hdr_size);
141 data_len = (phy->mode == S3FWRN5_MODE_NCI) ?
142 ((struct nci_ctrl_hdr *)hdr)->plen :
143 ((struct s3fwrn5_fw_header *)hdr)->len;
145 skb = alloc_skb(hdr_size + data_len, GFP_KERNEL);
149 skb_put_data(skb, hdr, hdr_size);
154 ret = i2c_master_recv(phy->i2c_dev, skb_put(skb, data_len), data_len);
155 if (ret != data_len) {
161 return s3fwrn5_recv_frame(phy->ndev, skb, phy->mode);
164 static irqreturn_t s3fwrn5_i2c_irq_thread_fn(int irq, void *phy_id)
166 struct s3fwrn5_i2c_phy *phy = phy_id;
168 if (!phy || !phy->ndev) {
173 mutex_lock(&phy->mutex);
179 case S3FWRN5_MODE_NCI:
180 case S3FWRN5_MODE_FW:
181 s3fwrn5_i2c_read(phy);
183 case S3FWRN5_MODE_COLD:
188 mutex_unlock(&phy->mutex);
193 static int s3fwrn5_i2c_parse_dt(struct i2c_client *client)
195 struct s3fwrn5_i2c_phy *phy = i2c_get_clientdata(client);
196 struct device_node *np = client->dev.of_node;
201 phy->gpio_en = of_get_named_gpio(np, "en-gpios", 0);
202 if (!gpio_is_valid(phy->gpio_en)) {
203 /* Support also deprecated property */
204 phy->gpio_en = of_get_named_gpio(np, "s3fwrn5,en-gpios", 0);
205 if (!gpio_is_valid(phy->gpio_en))
209 phy->gpio_fw_wake = of_get_named_gpio(np, "wake-gpios", 0);
210 if (!gpio_is_valid(phy->gpio_fw_wake)) {
211 /* Support also deprecated property */
212 phy->gpio_fw_wake = of_get_named_gpio(np, "s3fwrn5,fw-gpios", 0);
213 if (!gpio_is_valid(phy->gpio_fw_wake))
220 static int s3fwrn5_i2c_probe(struct i2c_client *client,
221 const struct i2c_device_id *id)
223 struct s3fwrn5_i2c_phy *phy;
226 phy = devm_kzalloc(&client->dev, sizeof(*phy), GFP_KERNEL);
230 mutex_init(&phy->mutex);
231 phy->mode = S3FWRN5_MODE_COLD;
232 phy->irq_skip = true;
234 phy->i2c_dev = client;
235 i2c_set_clientdata(client, phy);
237 ret = s3fwrn5_i2c_parse_dt(client);
241 ret = devm_gpio_request_one(&phy->i2c_dev->dev, phy->gpio_en,
242 GPIOF_OUT_INIT_HIGH, "s3fwrn5_en");
246 ret = devm_gpio_request_one(&phy->i2c_dev->dev, phy->gpio_fw_wake,
247 GPIOF_OUT_INIT_LOW, "s3fwrn5_fw_wake");
251 ret = s3fwrn5_probe(&phy->ndev, phy, &phy->i2c_dev->dev, &i2c_phy_ops,
252 S3FWRN5_I2C_MAX_PAYLOAD);
256 ret = devm_request_threaded_irq(&client->dev, phy->i2c_dev->irq, NULL,
257 s3fwrn5_i2c_irq_thread_fn, IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
258 S3FWRN5_I2C_DRIVER_NAME, phy);
260 s3fwrn5_remove(phy->ndev);
265 static int s3fwrn5_i2c_remove(struct i2c_client *client)
267 struct s3fwrn5_i2c_phy *phy = i2c_get_clientdata(client);
269 s3fwrn5_remove(phy->ndev);
274 static const struct i2c_device_id s3fwrn5_i2c_id_table[] = {
275 {S3FWRN5_I2C_DRIVER_NAME, 0},
278 MODULE_DEVICE_TABLE(i2c, s3fwrn5_i2c_id_table);
280 static const struct of_device_id of_s3fwrn5_i2c_match[] = {
281 { .compatible = "samsung,s3fwrn5-i2c", },
284 MODULE_DEVICE_TABLE(of, of_s3fwrn5_i2c_match);
286 static struct i2c_driver s3fwrn5_i2c_driver = {
288 .name = S3FWRN5_I2C_DRIVER_NAME,
289 .of_match_table = of_match_ptr(of_s3fwrn5_i2c_match),
291 .probe = s3fwrn5_i2c_probe,
292 .remove = s3fwrn5_i2c_remove,
293 .id_table = s3fwrn5_i2c_id_table,
296 module_i2c_driver(s3fwrn5_i2c_driver);
298 MODULE_LICENSE("GPL");
299 MODULE_DESCRIPTION("I2C driver for Samsung S3FWRN5");
300 MODULE_AUTHOR("Robert Baldyga <r.baldyga@samsung.com>");