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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * I2C Link Layer for ST NCI NFC controller familly based Driver
4 * Copyright (C) 2014-2015 STMicroelectronics SAS. All rights reserved.
5 */
6
7#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8
9#include <linux/module.h>
10#include <linux/i2c.h>
11#include <linux/gpio/consumer.h>
12#include <linux/acpi.h>
13#include <linux/interrupt.h>
14#include <linux/delay.h>
15#include <linux/nfc.h>
16#include <linux/of.h>
17
18#include "st-nci.h"
19
20#define DRIVER_DESC "NCI NFC driver for ST_NCI"
21
22/* ndlc header */
23#define ST_NCI_FRAME_HEADROOM 1
24#define ST_NCI_FRAME_TAILROOM 0
25
26#define ST_NCI_I2C_MIN_SIZE 4 /* PCB(1) + NCI Packet header(3) */
27#define ST_NCI_I2C_MAX_SIZE 250 /* req 4.2.1 */
28
29#define ST_NCI_DRIVER_NAME "st_nci"
30#define ST_NCI_I2C_DRIVER_NAME "st_nci_i2c"
31
32struct st_nci_i2c_phy {
33 struct i2c_client *i2c_dev;
34 struct llt_ndlc *ndlc;
35
36 bool irq_active;
37
38 struct gpio_desc *gpiod_reset;
39
40 struct st_nci_se_status se_status;
41};
42
43static int st_nci_i2c_enable(void *phy_id)
44{
45 struct st_nci_i2c_phy *phy = phy_id;
46
47 gpiod_set_value(phy->gpiod_reset, 0);
48 usleep_range(10000, 15000);
49 gpiod_set_value(phy->gpiod_reset, 1);
50 usleep_range(80000, 85000);
51
52 if (phy->ndlc->powered == 0 && phy->irq_active == 0) {
53 enable_irq(phy->i2c_dev->irq);
54 phy->irq_active = true;
55 }
56
57 return 0;
58}
59
60static void st_nci_i2c_disable(void *phy_id)
61{
62 struct st_nci_i2c_phy *phy = phy_id;
63
64 disable_irq_nosync(phy->i2c_dev->irq);
65 phy->irq_active = false;
66}
67
68/*
69 * Writing a frame must not return the number of written bytes.
70 * It must return either zero for success, or <0 for error.
71 * In addition, it must not alter the skb
72 */
73static int st_nci_i2c_write(void *phy_id, struct sk_buff *skb)
74{
75 int r;
76 struct st_nci_i2c_phy *phy = phy_id;
77 struct i2c_client *client = phy->i2c_dev;
78
79 if (phy->ndlc->hard_fault != 0)
80 return phy->ndlc->hard_fault;
81
82 r = i2c_master_send(client, skb->data, skb->len);
83 if (r < 0) { /* Retry, chip was in standby */
84 usleep_range(1000, 4000);
85 r = i2c_master_send(client, skb->data, skb->len);
86 }
87
88 if (r >= 0) {
89 if (r != skb->len)
90 r = -EREMOTEIO;
91 else
92 r = 0;
93 }
94
95 return r;
96}
97
98/*
99 * Reads an ndlc frame and returns it in a newly allocated sk_buff.
100 * returns:
101 * 0 : if received frame is complete
102 * -EREMOTEIO : i2c read error (fatal)
103 * -EBADMSG : frame was incorrect and discarded
104 * -ENOMEM : cannot allocate skb, frame dropped
105 */
106static int st_nci_i2c_read(struct st_nci_i2c_phy *phy,
107 struct sk_buff **skb)
108{
109 int r;
110 u8 len;
111 u8 buf[ST_NCI_I2C_MAX_SIZE];
112 struct i2c_client *client = phy->i2c_dev;
113
114 r = i2c_master_recv(client, buf, ST_NCI_I2C_MIN_SIZE);
115 if (r < 0) { /* Retry, chip was in standby */
116 usleep_range(1000, 4000);
117 r = i2c_master_recv(client, buf, ST_NCI_I2C_MIN_SIZE);
118 }
119
120 if (r != ST_NCI_I2C_MIN_SIZE)
121 return -EREMOTEIO;
122
123 len = be16_to_cpu(*(__be16 *) (buf + 2));
124 if (len > ST_NCI_I2C_MAX_SIZE) {
125 nfc_err(&client->dev, "invalid frame len\n");
126 return -EBADMSG;
127 }
128
129 *skb = alloc_skb(ST_NCI_I2C_MIN_SIZE + len, GFP_KERNEL);
130 if (*skb == NULL)
131 return -ENOMEM;
132
133 skb_reserve(*skb, ST_NCI_I2C_MIN_SIZE);
134 skb_put(*skb, ST_NCI_I2C_MIN_SIZE);
135 memcpy((*skb)->data, buf, ST_NCI_I2C_MIN_SIZE);
136
137 if (!len)
138 return 0;
139
140 r = i2c_master_recv(client, buf, len);
141 if (r != len) {
142 kfree_skb(*skb);
143 return -EREMOTEIO;
144 }
145
146 skb_put(*skb, len);
147 memcpy((*skb)->data + ST_NCI_I2C_MIN_SIZE, buf, len);
148
149 return 0;
150}
151
152/*
153 * Reads an ndlc frame from the chip.
154 *
155 * On ST_NCI, IRQ goes in idle state when read starts.
156 */
157static irqreturn_t st_nci_irq_thread_fn(int irq, void *phy_id)
158{
159 struct st_nci_i2c_phy *phy = phy_id;
160 struct i2c_client *client;
161 struct sk_buff *skb = NULL;
162 int r;
163
164 if (!phy || !phy->ndlc || irq != phy->i2c_dev->irq) {
165 WARN_ON_ONCE(1);
166 return IRQ_NONE;
167 }
168
169 client = phy->i2c_dev;
170 dev_dbg(&client->dev, "IRQ\n");
171
172 if (phy->ndlc->hard_fault)
173 return IRQ_HANDLED;
174
175 if (!phy->ndlc->powered) {
176 st_nci_i2c_disable(phy);
177 return IRQ_HANDLED;
178 }
179
180 r = st_nci_i2c_read(phy, &skb);
181 if (r == -EREMOTEIO || r == -ENOMEM || r == -EBADMSG)
182 return IRQ_HANDLED;
183
184 ndlc_recv(phy->ndlc, skb);
185
186 return IRQ_HANDLED;
187}
188
189static struct nfc_phy_ops i2c_phy_ops = {
190 .write = st_nci_i2c_write,
191 .enable = st_nci_i2c_enable,
192 .disable = st_nci_i2c_disable,
193};
194
195static const struct acpi_gpio_params reset_gpios = { 1, 0, false };
196
197static const struct acpi_gpio_mapping acpi_st_nci_gpios[] = {
198 { "reset-gpios", &reset_gpios, 1 },
199 {},
200};
201
202static int st_nci_i2c_probe(struct i2c_client *client,
203 const struct i2c_device_id *id)
204{
205 struct device *dev = &client->dev;
206 struct st_nci_i2c_phy *phy;
207 int r;
208
209 dev_dbg(&client->dev, "%s\n", __func__);
210 dev_dbg(&client->dev, "IRQ: %d\n", client->irq);
211
212 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
213 nfc_err(&client->dev, "Need I2C_FUNC_I2C\n");
214 return -ENODEV;
215 }
216
217 phy = devm_kzalloc(dev, sizeof(struct st_nci_i2c_phy), GFP_KERNEL);
218 if (!phy)
219 return -ENOMEM;
220
221 phy->i2c_dev = client;
222
223 i2c_set_clientdata(client, phy);
224
225 r = devm_acpi_dev_add_driver_gpios(dev, acpi_st_nci_gpios);
226 if (r)
227 dev_dbg(dev, "Unable to add GPIO mapping table\n");
228
229 /* Get RESET GPIO */
230 phy->gpiod_reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
231 if (IS_ERR(phy->gpiod_reset)) {
232 nfc_err(dev, "Unable to get RESET GPIO\n");
233 return -ENODEV;
234 }
235
236 phy->se_status.is_ese_present =
237 device_property_read_bool(dev, "ese-present");
238 phy->se_status.is_uicc_present =
239 device_property_read_bool(dev, "uicc-present");
240
241 r = ndlc_probe(phy, &i2c_phy_ops, &client->dev,
242 ST_NCI_FRAME_HEADROOM, ST_NCI_FRAME_TAILROOM,
243 &phy->ndlc, &phy->se_status);
244 if (r < 0) {
245 nfc_err(&client->dev, "Unable to register ndlc layer\n");
246 return r;
247 }
248
249 phy->irq_active = true;
250 r = devm_request_threaded_irq(&client->dev, client->irq, NULL,
251 st_nci_irq_thread_fn,
252 IRQF_ONESHOT,
253 ST_NCI_DRIVER_NAME, phy);
254 if (r < 0)
255 nfc_err(&client->dev, "Unable to register IRQ handler\n");
256
257 return r;
258}
259
260static int st_nci_i2c_remove(struct i2c_client *client)
261{
262 struct st_nci_i2c_phy *phy = i2c_get_clientdata(client);
263
264 dev_dbg(&client->dev, "%s\n", __func__);
265
266 ndlc_remove(phy->ndlc);
267
268 return 0;
269}
270
271static const struct i2c_device_id st_nci_i2c_id_table[] = {
272 {ST_NCI_DRIVER_NAME, 0},
273 {}
274};
275MODULE_DEVICE_TABLE(i2c, st_nci_i2c_id_table);
276
277static const struct acpi_device_id st_nci_i2c_acpi_match[] = {
278 {"SMO2101"},
279 {"SMO2102"},
280 {}
281};
282MODULE_DEVICE_TABLE(acpi, st_nci_i2c_acpi_match);
283
284static const struct of_device_id of_st_nci_i2c_match[] = {
285 { .compatible = "st,st21nfcb-i2c", },
286 { .compatible = "st,st21nfcb_i2c", },
287 { .compatible = "st,st21nfcc-i2c", },
288 {}
289};
290MODULE_DEVICE_TABLE(of, of_st_nci_i2c_match);
291
292static struct i2c_driver st_nci_i2c_driver = {
293 .driver = {
294 .name = ST_NCI_I2C_DRIVER_NAME,
295 .of_match_table = of_match_ptr(of_st_nci_i2c_match),
296 .acpi_match_table = ACPI_PTR(st_nci_i2c_acpi_match),
297 },
298 .probe = st_nci_i2c_probe,
299 .id_table = st_nci_i2c_id_table,
300 .remove = st_nci_i2c_remove,
301};
302module_i2c_driver(st_nci_i2c_driver);
303
304MODULE_LICENSE("GPL");
305MODULE_DESCRIPTION(DRIVER_DESC);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * I2C Link Layer for ST NCI NFC controller familly based Driver
4 * Copyright (C) 2014-2015 STMicroelectronics SAS. All rights reserved.
5 */
6
7#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8
9#include <linux/module.h>
10#include <linux/i2c.h>
11#include <linux/gpio/consumer.h>
12#include <linux/acpi.h>
13#include <linux/interrupt.h>
14#include <linux/delay.h>
15#include <linux/nfc.h>
16#include <linux/of.h>
17
18#include "st-nci.h"
19
20#define DRIVER_DESC "NCI NFC driver for ST_NCI"
21
22/* ndlc header */
23#define ST_NCI_FRAME_HEADROOM 1
24#define ST_NCI_FRAME_TAILROOM 0
25
26#define ST_NCI_I2C_MIN_SIZE 4 /* PCB(1) + NCI Packet header(3) */
27#define ST_NCI_I2C_MAX_SIZE 250 /* req 4.2.1 */
28
29#define ST_NCI_DRIVER_NAME "st_nci"
30#define ST_NCI_I2C_DRIVER_NAME "st_nci_i2c"
31
32struct st_nci_i2c_phy {
33 struct i2c_client *i2c_dev;
34 struct llt_ndlc *ndlc;
35
36 bool irq_active;
37
38 struct gpio_desc *gpiod_reset;
39
40 struct st_nci_se_status se_status;
41};
42
43static int st_nci_i2c_enable(void *phy_id)
44{
45 struct st_nci_i2c_phy *phy = phy_id;
46
47 gpiod_set_value(phy->gpiod_reset, 0);
48 usleep_range(10000, 15000);
49 gpiod_set_value(phy->gpiod_reset, 1);
50 usleep_range(80000, 85000);
51
52 if (phy->ndlc->powered == 0 && phy->irq_active == 0) {
53 enable_irq(phy->i2c_dev->irq);
54 phy->irq_active = true;
55 }
56
57 return 0;
58}
59
60static void st_nci_i2c_disable(void *phy_id)
61{
62 struct st_nci_i2c_phy *phy = phy_id;
63
64 disable_irq_nosync(phy->i2c_dev->irq);
65 phy->irq_active = false;
66}
67
68/*
69 * Writing a frame must not return the number of written bytes.
70 * It must return either zero for success, or <0 for error.
71 * In addition, it must not alter the skb
72 */
73static int st_nci_i2c_write(void *phy_id, struct sk_buff *skb)
74{
75 int r;
76 struct st_nci_i2c_phy *phy = phy_id;
77 struct i2c_client *client = phy->i2c_dev;
78
79 if (phy->ndlc->hard_fault != 0)
80 return phy->ndlc->hard_fault;
81
82 r = i2c_master_send(client, skb->data, skb->len);
83 if (r < 0) { /* Retry, chip was in standby */
84 usleep_range(1000, 4000);
85 r = i2c_master_send(client, skb->data, skb->len);
86 }
87
88 if (r >= 0) {
89 if (r != skb->len)
90 r = -EREMOTEIO;
91 else
92 r = 0;
93 }
94
95 return r;
96}
97
98/*
99 * Reads an ndlc frame and returns it in a newly allocated sk_buff.
100 * returns:
101 * 0 : if received frame is complete
102 * -EREMOTEIO : i2c read error (fatal)
103 * -EBADMSG : frame was incorrect and discarded
104 * -ENOMEM : cannot allocate skb, frame dropped
105 */
106static int st_nci_i2c_read(struct st_nci_i2c_phy *phy,
107 struct sk_buff **skb)
108{
109 int r;
110 u8 len;
111 u8 buf[ST_NCI_I2C_MAX_SIZE];
112 struct i2c_client *client = phy->i2c_dev;
113
114 r = i2c_master_recv(client, buf, ST_NCI_I2C_MIN_SIZE);
115 if (r < 0) { /* Retry, chip was in standby */
116 usleep_range(1000, 4000);
117 r = i2c_master_recv(client, buf, ST_NCI_I2C_MIN_SIZE);
118 }
119
120 if (r != ST_NCI_I2C_MIN_SIZE)
121 return -EREMOTEIO;
122
123 len = be16_to_cpu(*(__be16 *) (buf + 2));
124 if (len > ST_NCI_I2C_MAX_SIZE) {
125 nfc_err(&client->dev, "invalid frame len\n");
126 return -EBADMSG;
127 }
128
129 *skb = alloc_skb(ST_NCI_I2C_MIN_SIZE + len, GFP_KERNEL);
130 if (*skb == NULL)
131 return -ENOMEM;
132
133 skb_reserve(*skb, ST_NCI_I2C_MIN_SIZE);
134 skb_put(*skb, ST_NCI_I2C_MIN_SIZE);
135 memcpy((*skb)->data, buf, ST_NCI_I2C_MIN_SIZE);
136
137 if (!len)
138 return 0;
139
140 r = i2c_master_recv(client, buf, len);
141 if (r != len) {
142 kfree_skb(*skb);
143 return -EREMOTEIO;
144 }
145
146 skb_put(*skb, len);
147 memcpy((*skb)->data + ST_NCI_I2C_MIN_SIZE, buf, len);
148
149 return 0;
150}
151
152/*
153 * Reads an ndlc frame from the chip.
154 *
155 * On ST_NCI, IRQ goes in idle state when read starts.
156 */
157static irqreturn_t st_nci_irq_thread_fn(int irq, void *phy_id)
158{
159 struct st_nci_i2c_phy *phy = phy_id;
160 struct sk_buff *skb = NULL;
161 int r;
162
163 if (!phy || !phy->ndlc || irq != phy->i2c_dev->irq) {
164 WARN_ON_ONCE(1);
165 return IRQ_NONE;
166 }
167
168 if (phy->ndlc->hard_fault)
169 return IRQ_HANDLED;
170
171 if (!phy->ndlc->powered) {
172 st_nci_i2c_disable(phy);
173 return IRQ_HANDLED;
174 }
175
176 r = st_nci_i2c_read(phy, &skb);
177 if (r == -EREMOTEIO || r == -ENOMEM || r == -EBADMSG)
178 return IRQ_HANDLED;
179
180 ndlc_recv(phy->ndlc, skb);
181
182 return IRQ_HANDLED;
183}
184
185static const struct nfc_phy_ops i2c_phy_ops = {
186 .write = st_nci_i2c_write,
187 .enable = st_nci_i2c_enable,
188 .disable = st_nci_i2c_disable,
189};
190
191static const struct acpi_gpio_params reset_gpios = { 1, 0, false };
192
193static const struct acpi_gpio_mapping acpi_st_nci_gpios[] = {
194 { "reset-gpios", &reset_gpios, 1 },
195 {},
196};
197
198static int st_nci_i2c_probe(struct i2c_client *client)
199{
200 struct device *dev = &client->dev;
201 struct st_nci_i2c_phy *phy;
202 int r;
203
204 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
205 nfc_err(&client->dev, "Need I2C_FUNC_I2C\n");
206 return -ENODEV;
207 }
208
209 phy = devm_kzalloc(dev, sizeof(struct st_nci_i2c_phy), GFP_KERNEL);
210 if (!phy)
211 return -ENOMEM;
212
213 phy->i2c_dev = client;
214
215 i2c_set_clientdata(client, phy);
216
217 r = devm_acpi_dev_add_driver_gpios(dev, acpi_st_nci_gpios);
218 if (r)
219 dev_dbg(dev, "Unable to add GPIO mapping table\n");
220
221 /* Get RESET GPIO */
222 phy->gpiod_reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
223 if (IS_ERR(phy->gpiod_reset)) {
224 nfc_err(dev, "Unable to get RESET GPIO\n");
225 return -ENODEV;
226 }
227
228 phy->se_status.is_ese_present =
229 device_property_read_bool(dev, "ese-present");
230 phy->se_status.is_uicc_present =
231 device_property_read_bool(dev, "uicc-present");
232
233 r = ndlc_probe(phy, &i2c_phy_ops, &client->dev,
234 ST_NCI_FRAME_HEADROOM, ST_NCI_FRAME_TAILROOM,
235 &phy->ndlc, &phy->se_status);
236 if (r < 0) {
237 nfc_err(&client->dev, "Unable to register ndlc layer\n");
238 return r;
239 }
240
241 phy->irq_active = true;
242 r = devm_request_threaded_irq(&client->dev, client->irq, NULL,
243 st_nci_irq_thread_fn,
244 IRQF_ONESHOT,
245 ST_NCI_DRIVER_NAME, phy);
246 if (r < 0)
247 nfc_err(&client->dev, "Unable to register IRQ handler\n");
248
249 return r;
250}
251
252static void st_nci_i2c_remove(struct i2c_client *client)
253{
254 struct st_nci_i2c_phy *phy = i2c_get_clientdata(client);
255
256 ndlc_remove(phy->ndlc);
257}
258
259static const struct i2c_device_id st_nci_i2c_id_table[] = {
260 {ST_NCI_DRIVER_NAME, 0},
261 {}
262};
263MODULE_DEVICE_TABLE(i2c, st_nci_i2c_id_table);
264
265static const struct acpi_device_id st_nci_i2c_acpi_match[] __maybe_unused = {
266 {"SMO2101"},
267 {"SMO2102"},
268 {}
269};
270MODULE_DEVICE_TABLE(acpi, st_nci_i2c_acpi_match);
271
272static const struct of_device_id of_st_nci_i2c_match[] __maybe_unused = {
273 { .compatible = "st,st21nfcb-i2c", },
274 { .compatible = "st,st21nfcb_i2c", },
275 { .compatible = "st,st21nfcc-i2c", },
276 {}
277};
278MODULE_DEVICE_TABLE(of, of_st_nci_i2c_match);
279
280static struct i2c_driver st_nci_i2c_driver = {
281 .driver = {
282 .name = ST_NCI_I2C_DRIVER_NAME,
283 .of_match_table = of_match_ptr(of_st_nci_i2c_match),
284 .acpi_match_table = ACPI_PTR(st_nci_i2c_acpi_match),
285 },
286 .probe = st_nci_i2c_probe,
287 .id_table = st_nci_i2c_id_table,
288 .remove = st_nci_i2c_remove,
289};
290module_i2c_driver(st_nci_i2c_driver);
291
292MODULE_LICENSE("GPL");
293MODULE_DESCRIPTION(DRIVER_DESC);