1 /* -------------------------------------------------------------------------
2 * Copyright (C) 2014-2016, Intel Corporation
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 * -------------------------------------------------------------------------
16 #include <linux/module.h>
17 #include <linux/acpi.h>
18 #include <linux/i2c.h>
19 #include <linux/interrupt.h>
20 #include <linux/nfc.h>
21 #include <linux/delay.h>
22 #include <linux/gpio/consumer.h>
23 #include <net/nfc/nfc.h>
24 #include <net/nfc/nci_core.h>
28 #define FDP_I2C_DRIVER_NAME "fdp_nci_i2c"
30 #define FDP_DP_CLOCK_TYPE_NAME "clock-type"
31 #define FDP_DP_CLOCK_FREQ_NAME "clock-freq"
32 #define FDP_DP_FW_VSC_CFG_NAME "fw-vsc-cfg"
34 #define FDP_FRAME_HEADROOM 2
35 #define FDP_FRAME_TAILROOM 1
37 #define FDP_NCI_I2C_MIN_PAYLOAD 5
38 #define FDP_NCI_I2C_MAX_PAYLOAD 261
40 #define FDP_POWER_OFF 0
41 #define FDP_POWER_ON 1
43 #define fdp_nci_i2c_dump_skb(dev, prefix, skb) \
44 print_hex_dump(KERN_DEBUG, prefix": ", DUMP_PREFIX_OFFSET, \
45 16, 1, (skb)->data, (skb)->len, 0)
47 static void fdp_nci_i2c_reset(struct fdp_i2c_phy *phy)
49 /* Reset RST/WakeUP for at least 100 micro-second */
50 gpiod_set_value_cansleep(phy->power_gpio, FDP_POWER_OFF);
51 usleep_range(1000, 4000);
52 gpiod_set_value_cansleep(phy->power_gpio, FDP_POWER_ON);
53 usleep_range(10000, 14000);
56 static int fdp_nci_i2c_enable(void *phy_id)
58 struct fdp_i2c_phy *phy = phy_id;
60 dev_dbg(&phy->i2c_dev->dev, "%s\n", __func__);
61 fdp_nci_i2c_reset(phy);
66 static void fdp_nci_i2c_disable(void *phy_id)
68 struct fdp_i2c_phy *phy = phy_id;
70 dev_dbg(&phy->i2c_dev->dev, "%s\n", __func__);
71 fdp_nci_i2c_reset(phy);
74 static void fdp_nci_i2c_add_len_lrc(struct sk_buff *skb)
79 /* Add length header */
81 *(u8 *)skb_push(skb, 1) = len & 0xff;
82 *(u8 *)skb_push(skb, 1) = len >> 8;
84 /* Compute and add lrc */
85 for (i = 0; i < len + 2; i++)
91 static void fdp_nci_i2c_remove_len_lrc(struct sk_buff *skb)
93 skb_pull(skb, FDP_FRAME_HEADROOM);
94 skb_trim(skb, skb->len - FDP_FRAME_TAILROOM);
97 static int fdp_nci_i2c_write(void *phy_id, struct sk_buff *skb)
99 struct fdp_i2c_phy *phy = phy_id;
100 struct i2c_client *client = phy->i2c_dev;
103 if (phy->hard_fault != 0)
104 return phy->hard_fault;
106 fdp_nci_i2c_add_len_lrc(skb);
107 fdp_nci_i2c_dump_skb(&client->dev, "fdp_wr", skb);
109 r = i2c_master_send(client, skb->data, skb->len);
110 if (r == -EREMOTEIO) { /* Retry, chip was in standby */
111 usleep_range(1000, 4000);
112 r = i2c_master_send(client, skb->data, skb->len);
115 if (r < 0 || r != skb->len)
116 dev_dbg(&client->dev, "%s: error err=%d len=%d\n",
117 __func__, r, skb->len);
128 fdp_nci_i2c_remove_len_lrc(skb);
133 static struct nfc_phy_ops i2c_phy_ops = {
134 .write = fdp_nci_i2c_write,
135 .enable = fdp_nci_i2c_enable,
136 .disable = fdp_nci_i2c_disable,
139 static int fdp_nci_i2c_read(struct fdp_i2c_phy *phy, struct sk_buff **skb)
142 u8 tmp[FDP_NCI_I2C_MAX_PAYLOAD], lrc, k;
144 struct i2c_client *client = phy->i2c_dev;
148 /* Read the length packet and the data packet */
149 for (k = 0; k < 2; k++) {
151 len = phy->next_read_size;
153 r = i2c_master_recv(client, tmp, len);
155 dev_dbg(&client->dev, "%s: i2c recv err: %d\n",
160 /* Check packet integruty */
161 for (lrc = i = 0; i < r; i++)
165 * LRC check failed. This may due to transmission error or
166 * desynchronization between driver and FDP. Drop the paquet
167 * and force resynchronization
170 dev_dbg(&client->dev, "%s: corrupted packet\n",
172 phy->next_read_size = 5;
176 /* Packet that contains a length */
177 if (tmp[0] == 0 && tmp[1] == 0) {
178 phy->next_read_size = (tmp[2] << 8) + tmp[3] + 3;
180 phy->next_read_size = FDP_NCI_I2C_MIN_PAYLOAD;
182 *skb = alloc_skb(len, GFP_KERNEL);
188 skb_put_data(*skb, tmp, len);
189 fdp_nci_i2c_dump_skb(&client->dev, "fdp_rd", *skb);
191 fdp_nci_i2c_remove_len_lrc(*skb);
198 /* Flush the remaining data */
199 if (i2c_master_recv(client, tmp, sizeof(tmp)) < 0)
205 static irqreturn_t fdp_nci_i2c_irq_thread_fn(int irq, void *phy_id)
207 struct fdp_i2c_phy *phy = phy_id;
208 struct i2c_client *client;
212 if (!phy || irq != phy->i2c_dev->irq) {
217 client = phy->i2c_dev;
218 dev_dbg(&client->dev, "%s\n", __func__);
220 r = fdp_nci_i2c_read(phy, &skb);
224 else if (r == -ENOMEM || r == -EBADMSG)
228 fdp_nci_recv_frame(phy->ndev, skb);
233 static void fdp_nci_i2c_read_device_properties(struct device *dev,
234 u8 *clock_type, u32 *clock_freq,
240 r = device_property_read_u8(dev, FDP_DP_CLOCK_TYPE_NAME, clock_type);
242 dev_dbg(dev, "Using default clock type");
246 r = device_property_read_u32(dev, FDP_DP_CLOCK_FREQ_NAME, clock_freq);
248 dev_dbg(dev, "Using default clock frequency\n");
252 if (device_property_present(dev, FDP_DP_FW_VSC_CFG_NAME)) {
253 r = device_property_read_u8(dev, FDP_DP_FW_VSC_CFG_NAME,
259 /* Add 1 to the length to inclue the length byte itself */
262 *fw_vsc_cfg = devm_kmalloc(dev,
263 len * sizeof(**fw_vsc_cfg),
266 r = device_property_read_u8_array(dev, FDP_DP_FW_VSC_CFG_NAME,
270 devm_kfree(dev, *fw_vsc_cfg);
275 dev_dbg(dev, "FW vendor specific commands not present\n");
279 dev_dbg(dev, "Clock type: %d, clock frequency: %d, VSC: %s",
280 *clock_type, *clock_freq, *fw_vsc_cfg != NULL ? "yes" : "no");
283 static const struct acpi_gpio_params power_gpios = { 0, 0, false };
285 static const struct acpi_gpio_mapping acpi_fdp_gpios[] = {
286 { "power-gpios", &power_gpios, 1 },
290 static int fdp_nci_i2c_probe(struct i2c_client *client)
292 struct fdp_i2c_phy *phy;
293 struct device *dev = &client->dev;
299 dev_dbg(dev, "%s\n", __func__);
301 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
302 nfc_err(dev, "No I2C_FUNC_I2C support\n");
306 /* Checking if we have an irq */
307 if (client->irq <= 0) {
308 nfc_err(dev, "IRQ not present\n");
312 phy = devm_kzalloc(dev, sizeof(struct fdp_i2c_phy), GFP_KERNEL);
316 phy->i2c_dev = client;
317 phy->next_read_size = FDP_NCI_I2C_MIN_PAYLOAD;
318 i2c_set_clientdata(client, phy);
320 r = devm_request_threaded_irq(dev, client->irq,
321 NULL, fdp_nci_i2c_irq_thread_fn,
322 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
323 FDP_I2C_DRIVER_NAME, phy);
326 nfc_err(&client->dev, "Unable to register IRQ handler\n");
330 r = devm_acpi_dev_add_driver_gpios(dev, acpi_fdp_gpios);
332 dev_dbg(dev, "Unable to add GPIO mapping table\n");
334 /* Requesting the power gpio */
335 phy->power_gpio = devm_gpiod_get(dev, "power", GPIOD_OUT_LOW);
336 if (IS_ERR(phy->power_gpio)) {
337 nfc_err(dev, "Power GPIO request failed\n");
338 return PTR_ERR(phy->power_gpio);
341 /* read device properties to get the clock and production settings */
342 fdp_nci_i2c_read_device_properties(dev, &clock_type, &clock_freq,
345 /* Call the NFC specific probe function */
346 r = fdp_nci_probe(phy, &i2c_phy_ops, &phy->ndev,
347 FDP_FRAME_HEADROOM, FDP_FRAME_TAILROOM,
348 clock_type, clock_freq, fw_vsc_cfg);
350 nfc_err(dev, "NCI probing error\n");
354 dev_dbg(dev, "I2C driver loaded\n");
358 static int fdp_nci_i2c_remove(struct i2c_client *client)
360 struct fdp_i2c_phy *phy = i2c_get_clientdata(client);
362 dev_dbg(&client->dev, "%s\n", __func__);
364 fdp_nci_remove(phy->ndev);
365 fdp_nci_i2c_disable(phy);
370 static const struct acpi_device_id fdp_nci_i2c_acpi_match[] = {
374 MODULE_DEVICE_TABLE(acpi, fdp_nci_i2c_acpi_match);
376 static struct i2c_driver fdp_nci_i2c_driver = {
378 .name = FDP_I2C_DRIVER_NAME,
379 .acpi_match_table = ACPI_PTR(fdp_nci_i2c_acpi_match),
381 .probe_new = fdp_nci_i2c_probe,
382 .remove = fdp_nci_i2c_remove,
384 module_i2c_driver(fdp_nci_i2c_driver);
386 MODULE_LICENSE("GPL");
387 MODULE_DESCRIPTION("I2C driver for Intel Fields Peak NFC controller");
388 MODULE_AUTHOR("Robert Dolca <robert.dolca@intel.com>");