1 /* 2 * I2C link layer for the NXP NCI driver 3 * 4 * Copyright (C) 2014 NXP Semiconductors All rights reserved. 5 * Copyright (C) 2012-2015 Intel Corporation. All rights reserved. 6 * 7 * Authors: Clément Perrochaud <clement.perrochaud@nxp.com> 8 * Authors: Oleg Zhurakivskyy <oleg.zhurakivskyy@intel.com> 9 * 10 * Derived from PN544 device driver: 11 * Copyright (C) 2012 Intel Corporation. All rights reserved. 12 * 13 * This program is free software; you can redistribute it and/or modify it 14 * under the terms and conditions of the GNU General Public License, 15 * version 2, as published by the Free Software Foundation. 16 * 17 * This program is distributed in the hope that it will be useful, 18 * but WITHOUT ANY WARRANTY; without even the implied warranty of 19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 20 * GNU General Public License for more details. 21 * 22 * You should have received a copy of the GNU General Public License 23 * along with this program; if not, see <http://www.gnu.org/licenses/>. 24 */ 25 26 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 27 28 #include <linux/acpi.h> 29 #include <linux/delay.h> 30 #include <linux/i2c.h> 31 #include <linux/interrupt.h> 32 #include <linux/miscdevice.h> 33 #include <linux/module.h> 34 #include <linux/nfc.h> 35 #include <linux/gpio/consumer.h> 36 #include <linux/of_gpio.h> 37 #include <linux/of_irq.h> 38 #include <linux/platform_data/nxp-nci.h> 39 #include <linux/unaligned/access_ok.h> 40 41 #include <net/nfc/nfc.h> 42 43 #include "nxp-nci.h" 44 45 #define NXP_NCI_I2C_DRIVER_NAME "nxp-nci_i2c" 46 47 #define NXP_NCI_I2C_MAX_PAYLOAD 32 48 49 struct nxp_nci_i2c_phy { 50 struct i2c_client *i2c_dev; 51 struct nci_dev *ndev; 52 53 unsigned int gpio_en; 54 unsigned int gpio_fw; 55 unsigned int gpio_irq; 56 57 int hard_fault; /* 58 * < 0 if hardware error occurred (e.g. i2c err) 59 * and prevents normal operation. 60 */ 61 }; 62 63 static int nxp_nci_i2c_set_mode(void *phy_id, 64 enum nxp_nci_mode mode) 65 { 66 struct nxp_nci_i2c_phy *phy = (struct nxp_nci_i2c_phy *) phy_id; 67 68 gpio_set_value(phy->gpio_fw, (mode == NXP_NCI_MODE_FW) ? 1 : 0); 69 gpio_set_value(phy->gpio_en, (mode != NXP_NCI_MODE_COLD) ? 1 : 0); 70 usleep_range(10000, 15000); 71 72 if (mode == NXP_NCI_MODE_COLD) 73 phy->hard_fault = 0; 74 75 return 0; 76 } 77 78 static int nxp_nci_i2c_write(void *phy_id, struct sk_buff *skb) 79 { 80 int r; 81 struct nxp_nci_i2c_phy *phy = phy_id; 82 struct i2c_client *client = phy->i2c_dev; 83 84 if (phy->hard_fault != 0) 85 return phy->hard_fault; 86 87 r = i2c_master_send(client, skb->data, skb->len); 88 if (r == -EREMOTEIO) { 89 /* Retry, chip was in standby */ 90 usleep_range(110000, 120000); 91 r = i2c_master_send(client, skb->data, skb->len); 92 } 93 94 if (r < 0) { 95 nfc_err(&client->dev, "Error %d on I2C send\n", r); 96 } else if (r != skb->len) { 97 nfc_err(&client->dev, 98 "Invalid length sent: %u (expected %u)\n", 99 r, skb->len); 100 r = -EREMOTEIO; 101 } else { 102 /* Success but return 0 and not number of bytes */ 103 r = 0; 104 } 105 106 return r; 107 } 108 109 static struct nxp_nci_phy_ops i2c_phy_ops = { 110 .set_mode = nxp_nci_i2c_set_mode, 111 .write = nxp_nci_i2c_write, 112 }; 113 114 static int nxp_nci_i2c_fw_read(struct nxp_nci_i2c_phy *phy, 115 struct sk_buff **skb) 116 { 117 struct i2c_client *client = phy->i2c_dev; 118 u16 header; 119 size_t frame_len; 120 int r; 121 122 r = i2c_master_recv(client, (u8 *) &header, NXP_NCI_FW_HDR_LEN); 123 if (r < 0) { 124 goto fw_read_exit; 125 } else if (r != NXP_NCI_FW_HDR_LEN) { 126 nfc_err(&client->dev, "Incorrect header length: %u\n", r); 127 r = -EBADMSG; 128 goto fw_read_exit; 129 } 130 131 frame_len = (get_unaligned_be16(&header) & NXP_NCI_FW_FRAME_LEN_MASK) + 132 NXP_NCI_FW_CRC_LEN; 133 134 *skb = alloc_skb(NXP_NCI_FW_HDR_LEN + frame_len, GFP_KERNEL); 135 if (*skb == NULL) { 136 r = -ENOMEM; 137 goto fw_read_exit; 138 } 139 140 memcpy(skb_put(*skb, NXP_NCI_FW_HDR_LEN), &header, NXP_NCI_FW_HDR_LEN); 141 142 r = i2c_master_recv(client, skb_put(*skb, frame_len), frame_len); 143 if (r != frame_len) { 144 nfc_err(&client->dev, 145 "Invalid frame length: %u (expected %zu)\n", 146 r, frame_len); 147 r = -EBADMSG; 148 goto fw_read_exit_free_skb; 149 } 150 151 return 0; 152 153 fw_read_exit_free_skb: 154 kfree_skb(*skb); 155 fw_read_exit: 156 return r; 157 } 158 159 static int nxp_nci_i2c_nci_read(struct nxp_nci_i2c_phy *phy, 160 struct sk_buff **skb) 161 { 162 struct nci_ctrl_hdr header; /* May actually be a data header */ 163 struct i2c_client *client = phy->i2c_dev; 164 int r; 165 166 r = i2c_master_recv(client, (u8 *) &header, NCI_CTRL_HDR_SIZE); 167 if (r < 0) { 168 goto nci_read_exit; 169 } else if (r != NCI_CTRL_HDR_SIZE) { 170 nfc_err(&client->dev, "Incorrect header length: %u\n", r); 171 r = -EBADMSG; 172 goto nci_read_exit; 173 } 174 175 *skb = alloc_skb(NCI_CTRL_HDR_SIZE + header.plen, GFP_KERNEL); 176 if (*skb == NULL) { 177 r = -ENOMEM; 178 goto nci_read_exit; 179 } 180 181 memcpy(skb_put(*skb, NCI_CTRL_HDR_SIZE), (void *) &header, 182 NCI_CTRL_HDR_SIZE); 183 184 r = i2c_master_recv(client, skb_put(*skb, header.plen), header.plen); 185 if (r != header.plen) { 186 nfc_err(&client->dev, 187 "Invalid frame payload length: %u (expected %u)\n", 188 r, header.plen); 189 r = -EBADMSG; 190 goto nci_read_exit_free_skb; 191 } 192 193 return 0; 194 195 nci_read_exit_free_skb: 196 kfree_skb(*skb); 197 nci_read_exit: 198 return r; 199 } 200 201 static irqreturn_t nxp_nci_i2c_irq_thread_fn(int irq, void *phy_id) 202 { 203 struct nxp_nci_i2c_phy *phy = phy_id; 204 struct i2c_client *client; 205 struct nxp_nci_info *info; 206 207 struct sk_buff *skb = NULL; 208 int r = 0; 209 210 if (!phy || !phy->ndev) 211 goto exit_irq_none; 212 213 client = phy->i2c_dev; 214 215 if (!client || irq != client->irq) 216 goto exit_irq_none; 217 218 info = nci_get_drvdata(phy->ndev); 219 220 if (!info) 221 goto exit_irq_none; 222 223 mutex_lock(&info->info_lock); 224 225 if (phy->hard_fault != 0) 226 goto exit_irq_handled; 227 228 switch (info->mode) { 229 case NXP_NCI_MODE_NCI: 230 r = nxp_nci_i2c_nci_read(phy, &skb); 231 break; 232 case NXP_NCI_MODE_FW: 233 r = nxp_nci_i2c_fw_read(phy, &skb); 234 break; 235 case NXP_NCI_MODE_COLD: 236 r = -EREMOTEIO; 237 break; 238 } 239 240 if (r == -EREMOTEIO) { 241 phy->hard_fault = r; 242 skb = NULL; 243 } else if (r < 0) { 244 nfc_err(&client->dev, "Read failed with error %d\n", r); 245 goto exit_irq_handled; 246 } 247 248 switch (info->mode) { 249 case NXP_NCI_MODE_NCI: 250 nci_recv_frame(phy->ndev, skb); 251 break; 252 case NXP_NCI_MODE_FW: 253 nxp_nci_fw_recv_frame(phy->ndev, skb); 254 break; 255 case NXP_NCI_MODE_COLD: 256 break; 257 } 258 259 exit_irq_handled: 260 mutex_unlock(&info->info_lock); 261 return IRQ_HANDLED; 262 exit_irq_none: 263 WARN_ON_ONCE(1); 264 return IRQ_NONE; 265 } 266 267 #ifdef CONFIG_OF 268 269 static int nxp_nci_i2c_parse_devtree(struct i2c_client *client) 270 { 271 struct nxp_nci_i2c_phy *phy = i2c_get_clientdata(client); 272 struct device_node *pp; 273 int r; 274 275 pp = client->dev.of_node; 276 if (!pp) 277 return -ENODEV; 278 279 r = of_get_named_gpio(pp, "enable-gpios", 0); 280 if (r == -EPROBE_DEFER) 281 r = of_get_named_gpio(pp, "enable-gpios", 0); 282 if (r < 0) { 283 nfc_err(&client->dev, "Failed to get EN gpio, error: %d\n", r); 284 return r; 285 } 286 phy->gpio_en = r; 287 288 r = of_get_named_gpio(pp, "firmware-gpios", 0); 289 if (r == -EPROBE_DEFER) 290 r = of_get_named_gpio(pp, "firmware-gpios", 0); 291 if (r < 0) { 292 nfc_err(&client->dev, "Failed to get FW gpio, error: %d\n", r); 293 return r; 294 } 295 phy->gpio_fw = r; 296 297 r = irq_of_parse_and_map(pp, 0); 298 if (r < 0) { 299 nfc_err(&client->dev, "Unable to get irq, error: %d\n", r); 300 return r; 301 } 302 client->irq = r; 303 304 return 0; 305 } 306 307 #else 308 309 static int nxp_nci_i2c_parse_devtree(struct i2c_client *client) 310 { 311 return -ENODEV; 312 } 313 314 #endif 315 316 static int nxp_nci_i2c_acpi_config(struct nxp_nci_i2c_phy *phy) 317 { 318 struct i2c_client *client = phy->i2c_dev; 319 struct gpio_desc *gpiod_en, *gpiod_fw, *gpiod_irq; 320 321 gpiod_en = devm_gpiod_get_index(&client->dev, NULL, 2); 322 gpiod_fw = devm_gpiod_get_index(&client->dev, NULL, 1); 323 gpiod_irq = devm_gpiod_get_index(&client->dev, NULL, 0); 324 325 if (IS_ERR(gpiod_en) || IS_ERR(gpiod_fw) || IS_ERR(gpiod_irq)) { 326 nfc_err(&client->dev, "No GPIOs\n"); 327 return -EINVAL; 328 } 329 330 gpiod_direction_output(gpiod_en, 0); 331 gpiod_direction_output(gpiod_fw, 0); 332 gpiod_direction_input(gpiod_irq); 333 334 client->irq = gpiod_to_irq(gpiod_irq); 335 if (client->irq < 0) { 336 nfc_err(&client->dev, "No IRQ\n"); 337 return -EINVAL; 338 } 339 340 phy->gpio_en = desc_to_gpio(gpiod_en); 341 phy->gpio_fw = desc_to_gpio(gpiod_fw); 342 phy->gpio_irq = desc_to_gpio(gpiod_irq); 343 344 return 0; 345 } 346 347 static int nxp_nci_i2c_probe(struct i2c_client *client, 348 const struct i2c_device_id *id) 349 { 350 struct nxp_nci_i2c_phy *phy; 351 struct nxp_nci_nfc_platform_data *pdata; 352 int r; 353 354 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { 355 nfc_err(&client->dev, "Need I2C_FUNC_I2C\n"); 356 r = -ENODEV; 357 goto probe_exit; 358 } 359 360 phy = devm_kzalloc(&client->dev, sizeof(struct nxp_nci_i2c_phy), 361 GFP_KERNEL); 362 if (!phy) { 363 r = -ENOMEM; 364 goto probe_exit; 365 } 366 367 phy->i2c_dev = client; 368 i2c_set_clientdata(client, phy); 369 370 pdata = client->dev.platform_data; 371 372 if (!pdata && client->dev.of_node) { 373 r = nxp_nci_i2c_parse_devtree(client); 374 if (r < 0) { 375 nfc_err(&client->dev, "Failed to get DT data\n"); 376 goto probe_exit; 377 } 378 } else if (pdata) { 379 phy->gpio_en = pdata->gpio_en; 380 phy->gpio_fw = pdata->gpio_fw; 381 client->irq = pdata->irq; 382 } else if (ACPI_HANDLE(&client->dev)) { 383 r = nxp_nci_i2c_acpi_config(phy); 384 if (r < 0) 385 goto probe_exit; 386 goto nci_probe; 387 } else { 388 nfc_err(&client->dev, "No platform data\n"); 389 r = -EINVAL; 390 goto probe_exit; 391 } 392 393 r = devm_gpio_request_one(&phy->i2c_dev->dev, phy->gpio_en, 394 GPIOF_OUT_INIT_LOW, "nxp_nci_en"); 395 if (r < 0) 396 goto probe_exit; 397 398 r = devm_gpio_request_one(&phy->i2c_dev->dev, phy->gpio_fw, 399 GPIOF_OUT_INIT_LOW, "nxp_nci_fw"); 400 if (r < 0) 401 goto probe_exit; 402 403 nci_probe: 404 r = nxp_nci_probe(phy, &client->dev, &i2c_phy_ops, 405 NXP_NCI_I2C_MAX_PAYLOAD, &phy->ndev); 406 if (r < 0) 407 goto probe_exit; 408 409 r = request_threaded_irq(client->irq, NULL, 410 nxp_nci_i2c_irq_thread_fn, 411 IRQF_TRIGGER_RISING | IRQF_ONESHOT, 412 NXP_NCI_I2C_DRIVER_NAME, phy); 413 if (r < 0) 414 nfc_err(&client->dev, "Unable to register IRQ handler\n"); 415 416 probe_exit: 417 return r; 418 } 419 420 static int nxp_nci_i2c_remove(struct i2c_client *client) 421 { 422 struct nxp_nci_i2c_phy *phy = i2c_get_clientdata(client); 423 424 nxp_nci_remove(phy->ndev); 425 free_irq(client->irq, phy); 426 427 return 0; 428 } 429 430 static struct i2c_device_id nxp_nci_i2c_id_table[] = { 431 {"nxp-nci_i2c", 0}, 432 {} 433 }; 434 MODULE_DEVICE_TABLE(i2c, nxp_nci_i2c_id_table); 435 436 static const struct of_device_id of_nxp_nci_i2c_match[] = { 437 { .compatible = "nxp,nxp-nci-i2c", }, 438 {}, 439 }; 440 MODULE_DEVICE_TABLE(of, of_nxp_nci_i2c_match); 441 442 #ifdef CONFIG_ACPI 443 static struct acpi_device_id acpi_id[] = { 444 { "NXP7471" }, 445 { }, 446 }; 447 MODULE_DEVICE_TABLE(acpi, acpi_id); 448 #endif 449 450 static struct i2c_driver nxp_nci_i2c_driver = { 451 .driver = { 452 .name = NXP_NCI_I2C_DRIVER_NAME, 453 .owner = THIS_MODULE, 454 .acpi_match_table = ACPI_PTR(acpi_id), 455 .of_match_table = of_match_ptr(of_nxp_nci_i2c_match), 456 }, 457 .probe = nxp_nci_i2c_probe, 458 .id_table = nxp_nci_i2c_id_table, 459 .remove = nxp_nci_i2c_remove, 460 }; 461 462 module_i2c_driver(nxp_nci_i2c_driver); 463 464 MODULE_LICENSE("GPL"); 465 MODULE_DESCRIPTION("I2C driver for NXP NCI NFC controllers"); 466 MODULE_AUTHOR("Clément Perrochaud <clement.perrochaud@nxp.com>"); 467 MODULE_AUTHOR("Oleg Zhurakivskyy <oleg.zhurakivskyy@intel.com>"); 468