cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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i2c.c (24385B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * I2C Link Layer for PN544 HCI based Driver
      4 *
      5 * Copyright (C) 2012  Intel Corporation. All rights reserved.
      6 */
      7
      8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
      9
     10#include <linux/crc-ccitt.h>
     11#include <linux/module.h>
     12#include <linux/i2c.h>
     13#include <linux/acpi.h>
     14#include <linux/interrupt.h>
     15#include <linux/delay.h>
     16#include <linux/nfc.h>
     17#include <linux/firmware.h>
     18#include <linux/gpio/consumer.h>
     19
     20#include <asm/unaligned.h>
     21
     22#include <net/nfc/hci.h>
     23#include <net/nfc/llc.h>
     24#include <net/nfc/nfc.h>
     25
     26#include "pn544.h"
     27
     28#define PN544_I2C_FRAME_HEADROOM 1
     29#define PN544_I2C_FRAME_TAILROOM 2
     30
     31/* GPIO names */
     32#define PN544_GPIO_NAME_IRQ "pn544_irq"
     33#define PN544_GPIO_NAME_FW  "pn544_fw"
     34#define PN544_GPIO_NAME_EN  "pn544_en"
     35
     36/* framing in HCI mode */
     37#define PN544_HCI_I2C_LLC_LEN		1
     38#define PN544_HCI_I2C_LLC_CRC		2
     39#define PN544_HCI_I2C_LLC_LEN_CRC	(PN544_HCI_I2C_LLC_LEN + \
     40					 PN544_HCI_I2C_LLC_CRC)
     41#define PN544_HCI_I2C_LLC_MIN_SIZE	(1 + PN544_HCI_I2C_LLC_LEN_CRC)
     42#define PN544_HCI_I2C_LLC_MAX_PAYLOAD	29
     43#define PN544_HCI_I2C_LLC_MAX_SIZE	(PN544_HCI_I2C_LLC_LEN_CRC + 1 + \
     44					 PN544_HCI_I2C_LLC_MAX_PAYLOAD)
     45
     46static const struct i2c_device_id pn544_hci_i2c_id_table[] = {
     47	{"pn544", 0},
     48	{}
     49};
     50
     51MODULE_DEVICE_TABLE(i2c, pn544_hci_i2c_id_table);
     52
     53static const struct acpi_device_id pn544_hci_i2c_acpi_match[] __maybe_unused = {
     54	{"NXP5440", 0},
     55	{}
     56};
     57
     58MODULE_DEVICE_TABLE(acpi, pn544_hci_i2c_acpi_match);
     59
     60#define PN544_HCI_I2C_DRIVER_NAME "pn544_hci_i2c"
     61
     62/*
     63 * Exposed through the 4 most significant bytes
     64 * from the HCI SW_VERSION first byte, a.k.a.
     65 * SW RomLib.
     66 */
     67#define PN544_HW_VARIANT_C2 0xa
     68#define PN544_HW_VARIANT_C3 0xb
     69
     70#define PN544_FW_CMD_RESET 0x01
     71#define PN544_FW_CMD_WRITE 0x08
     72#define PN544_FW_CMD_CHECK 0x06
     73#define PN544_FW_CMD_SECURE_WRITE 0x0C
     74#define PN544_FW_CMD_SECURE_CHUNK_WRITE 0x0D
     75
     76struct pn544_i2c_fw_frame_write {
     77	u8 cmd;
     78	u16 be_length;
     79	u8 be_dest_addr[3];
     80	u16 be_datalen;
     81	u8 data[];
     82} __packed;
     83
     84struct pn544_i2c_fw_frame_check {
     85	u8 cmd;
     86	u16 be_length;
     87	u8 be_start_addr[3];
     88	u16 be_datalen;
     89	u16 be_crc;
     90} __packed;
     91
     92struct pn544_i2c_fw_frame_response {
     93	u8 status;
     94	u16 be_length;
     95} __packed;
     96
     97struct pn544_i2c_fw_blob {
     98	u32 be_size;
     99	u32 be_destaddr;
    100	u8 data[];
    101};
    102
    103struct pn544_i2c_fw_secure_frame {
    104	u8 cmd;
    105	u16 be_datalen;
    106	u8 data[];
    107} __packed;
    108
    109struct pn544_i2c_fw_secure_blob {
    110	u64 header;
    111	u8 data[];
    112};
    113
    114#define PN544_FW_CMD_RESULT_TIMEOUT 0x01
    115#define PN544_FW_CMD_RESULT_BAD_CRC 0x02
    116#define PN544_FW_CMD_RESULT_ACCESS_DENIED 0x08
    117#define PN544_FW_CMD_RESULT_PROTOCOL_ERROR 0x0B
    118#define PN544_FW_CMD_RESULT_INVALID_PARAMETER 0x11
    119#define PN544_FW_CMD_RESULT_UNSUPPORTED_COMMAND 0x13
    120#define PN544_FW_CMD_RESULT_INVALID_LENGTH 0x18
    121#define PN544_FW_CMD_RESULT_CRYPTOGRAPHIC_ERROR 0x19
    122#define PN544_FW_CMD_RESULT_VERSION_CONDITIONS_ERROR 0x1D
    123#define PN544_FW_CMD_RESULT_MEMORY_ERROR 0x20
    124#define PN544_FW_CMD_RESULT_CHUNK_OK 0x21
    125#define PN544_FW_CMD_RESULT_WRITE_FAILED 0x74
    126#define PN544_FW_CMD_RESULT_COMMAND_REJECTED 0xE0
    127#define PN544_FW_CMD_RESULT_CHUNK_ERROR 0xE6
    128
    129#define MIN(X, Y) ((X) < (Y) ? (X) : (Y))
    130
    131#define PN544_FW_WRITE_BUFFER_MAX_LEN 0x9f7
    132#define PN544_FW_I2C_MAX_PAYLOAD PN544_HCI_I2C_LLC_MAX_SIZE
    133#define PN544_FW_I2C_WRITE_FRAME_HEADER_LEN 8
    134#define PN544_FW_I2C_WRITE_DATA_MAX_LEN MIN((PN544_FW_I2C_MAX_PAYLOAD -\
    135					 PN544_FW_I2C_WRITE_FRAME_HEADER_LEN),\
    136					 PN544_FW_WRITE_BUFFER_MAX_LEN)
    137#define PN544_FW_SECURE_CHUNK_WRITE_HEADER_LEN 3
    138#define PN544_FW_SECURE_CHUNK_WRITE_DATA_MAX_LEN (PN544_FW_I2C_MAX_PAYLOAD -\
    139			PN544_FW_SECURE_CHUNK_WRITE_HEADER_LEN)
    140#define PN544_FW_SECURE_FRAME_HEADER_LEN 3
    141#define PN544_FW_SECURE_BLOB_HEADER_LEN 8
    142
    143#define FW_WORK_STATE_IDLE 1
    144#define FW_WORK_STATE_START 2
    145#define FW_WORK_STATE_WAIT_WRITE_ANSWER 3
    146#define FW_WORK_STATE_WAIT_CHECK_ANSWER 4
    147#define FW_WORK_STATE_WAIT_SECURE_WRITE_ANSWER 5
    148
    149struct pn544_i2c_phy {
    150	struct i2c_client *i2c_dev;
    151	struct nfc_hci_dev *hdev;
    152
    153	struct gpio_desc *gpiod_en;
    154	struct gpio_desc *gpiod_fw;
    155
    156	unsigned int en_polarity;
    157
    158	u8 hw_variant;
    159
    160	struct work_struct fw_work;
    161	int fw_work_state;
    162	char firmware_name[NFC_FIRMWARE_NAME_MAXSIZE + 1];
    163	const struct firmware *fw;
    164	u32 fw_blob_dest_addr;
    165	size_t fw_blob_size;
    166	const u8 *fw_blob_data;
    167	size_t fw_written;
    168	size_t fw_size;
    169
    170	int fw_cmd_result;
    171
    172	int powered;
    173	int run_mode;
    174
    175	int hard_fault;		/*
    176				 * < 0 if hardware error occured (e.g. i2c err)
    177				 * and prevents normal operation.
    178				 */
    179};
    180
    181#define I2C_DUMP_SKB(info, skb)					\
    182do {								\
    183	pr_debug("%s:\n", info);				\
    184	print_hex_dump(KERN_DEBUG, "i2c: ", DUMP_PREFIX_OFFSET,	\
    185		       16, 1, (skb)->data, (skb)->len, 0);	\
    186} while (0)
    187
    188static void pn544_hci_i2c_platform_init(struct pn544_i2c_phy *phy)
    189{
    190	int polarity, retry, ret;
    191	static const char rset_cmd[] = { 0x05, 0xF9, 0x04, 0x00, 0xC3, 0xE5 };
    192	int count = sizeof(rset_cmd);
    193
    194	nfc_info(&phy->i2c_dev->dev, "Detecting nfc_en polarity\n");
    195
    196	/* Disable fw download */
    197	gpiod_set_value_cansleep(phy->gpiod_fw, 0);
    198
    199	for (polarity = 0; polarity < 2; polarity++) {
    200		phy->en_polarity = polarity;
    201		retry = 3;
    202		while (retry--) {
    203			/* power off */
    204			gpiod_set_value_cansleep(phy->gpiod_en, !phy->en_polarity);
    205			usleep_range(10000, 15000);
    206
    207			/* power on */
    208			gpiod_set_value_cansleep(phy->gpiod_en, phy->en_polarity);
    209			usleep_range(10000, 15000);
    210
    211			/* send reset */
    212			dev_dbg(&phy->i2c_dev->dev, "Sending reset cmd\n");
    213			ret = i2c_master_send(phy->i2c_dev, rset_cmd, count);
    214			if (ret == count) {
    215				nfc_info(&phy->i2c_dev->dev,
    216					 "nfc_en polarity : active %s\n",
    217					 (polarity == 0 ? "low" : "high"));
    218				goto out;
    219			}
    220		}
    221	}
    222
    223	nfc_err(&phy->i2c_dev->dev,
    224		"Could not detect nfc_en polarity, fallback to active high\n");
    225
    226out:
    227	gpiod_set_value_cansleep(phy->gpiod_en, !phy->en_polarity);
    228	usleep_range(10000, 15000);
    229}
    230
    231static void pn544_hci_i2c_enable_mode(struct pn544_i2c_phy *phy, int run_mode)
    232{
    233	gpiod_set_value_cansleep(phy->gpiod_fw, run_mode == PN544_FW_MODE ? 1 : 0);
    234	gpiod_set_value_cansleep(phy->gpiod_en, phy->en_polarity);
    235	usleep_range(10000, 15000);
    236
    237	phy->run_mode = run_mode;
    238}
    239
    240static int pn544_hci_i2c_enable(void *phy_id)
    241{
    242	struct pn544_i2c_phy *phy = phy_id;
    243
    244	pn544_hci_i2c_enable_mode(phy, PN544_HCI_MODE);
    245
    246	phy->powered = 1;
    247
    248	return 0;
    249}
    250
    251static void pn544_hci_i2c_disable(void *phy_id)
    252{
    253	struct pn544_i2c_phy *phy = phy_id;
    254
    255	gpiod_set_value_cansleep(phy->gpiod_fw, 0);
    256	gpiod_set_value_cansleep(phy->gpiod_en, !phy->en_polarity);
    257	usleep_range(10000, 15000);
    258
    259	gpiod_set_value_cansleep(phy->gpiod_en, phy->en_polarity);
    260	usleep_range(10000, 15000);
    261
    262	gpiod_set_value_cansleep(phy->gpiod_en, !phy->en_polarity);
    263	usleep_range(10000, 15000);
    264
    265	phy->powered = 0;
    266}
    267
    268static void pn544_hci_i2c_add_len_crc(struct sk_buff *skb)
    269{
    270	u16 crc;
    271	int len;
    272
    273	len = skb->len + 2;
    274	*(u8 *)skb_push(skb, 1) = len;
    275
    276	crc = crc_ccitt(0xffff, skb->data, skb->len);
    277	crc = ~crc;
    278	skb_put_u8(skb, crc & 0xff);
    279	skb_put_u8(skb, crc >> 8);
    280}
    281
    282static void pn544_hci_i2c_remove_len_crc(struct sk_buff *skb)
    283{
    284	skb_pull(skb, PN544_I2C_FRAME_HEADROOM);
    285	skb_trim(skb, PN544_I2C_FRAME_TAILROOM);
    286}
    287
    288/*
    289 * Writing a frame must not return the number of written bytes.
    290 * It must return either zero for success, or <0 for error.
    291 * In addition, it must not alter the skb
    292 */
    293static int pn544_hci_i2c_write(void *phy_id, struct sk_buff *skb)
    294{
    295	int r;
    296	struct pn544_i2c_phy *phy = phy_id;
    297	struct i2c_client *client = phy->i2c_dev;
    298
    299	if (phy->hard_fault != 0)
    300		return phy->hard_fault;
    301
    302	usleep_range(3000, 6000);
    303
    304	pn544_hci_i2c_add_len_crc(skb);
    305
    306	I2C_DUMP_SKB("i2c frame written", skb);
    307
    308	r = i2c_master_send(client, skb->data, skb->len);
    309
    310	if (r == -EREMOTEIO) {	/* Retry, chip was in standby */
    311		usleep_range(6000, 10000);
    312		r = i2c_master_send(client, skb->data, skb->len);
    313	}
    314
    315	if (r >= 0) {
    316		if (r != skb->len)
    317			r = -EREMOTEIO;
    318		else
    319			r = 0;
    320	}
    321
    322	pn544_hci_i2c_remove_len_crc(skb);
    323
    324	return r;
    325}
    326
    327static int check_crc(u8 *buf, int buflen)
    328{
    329	int len;
    330	u16 crc;
    331
    332	len = buf[0] + 1;
    333	crc = crc_ccitt(0xffff, buf, len - 2);
    334	crc = ~crc;
    335
    336	if (buf[len - 2] != (crc & 0xff) || buf[len - 1] != (crc >> 8)) {
    337		pr_err("CRC error 0x%x != 0x%x 0x%x\n",
    338		       crc, buf[len - 1], buf[len - 2]);
    339		pr_info("%s: BAD CRC\n", __func__);
    340		print_hex_dump(KERN_DEBUG, "crc: ", DUMP_PREFIX_NONE,
    341			       16, 2, buf, buflen, false);
    342		return -EPERM;
    343	}
    344	return 0;
    345}
    346
    347/*
    348 * Reads an shdlc frame and returns it in a newly allocated sk_buff. Guarantees
    349 * that i2c bus will be flushed and that next read will start on a new frame.
    350 * returned skb contains only LLC header and payload.
    351 * returns:
    352 * -EREMOTEIO : i2c read error (fatal)
    353 * -EBADMSG : frame was incorrect and discarded
    354 * -ENOMEM : cannot allocate skb, frame dropped
    355 */
    356static int pn544_hci_i2c_read(struct pn544_i2c_phy *phy, struct sk_buff **skb)
    357{
    358	int r;
    359	u8 len;
    360	u8 tmp[PN544_HCI_I2C_LLC_MAX_SIZE - 1];
    361	struct i2c_client *client = phy->i2c_dev;
    362
    363	r = i2c_master_recv(client, &len, 1);
    364	if (r != 1) {
    365		nfc_err(&client->dev, "cannot read len byte\n");
    366		return -EREMOTEIO;
    367	}
    368
    369	if ((len < (PN544_HCI_I2C_LLC_MIN_SIZE - 1)) ||
    370	    (len > (PN544_HCI_I2C_LLC_MAX_SIZE - 1))) {
    371		nfc_err(&client->dev, "invalid len byte\n");
    372		r = -EBADMSG;
    373		goto flush;
    374	}
    375
    376	*skb = alloc_skb(1 + len, GFP_KERNEL);
    377	if (*skb == NULL) {
    378		r = -ENOMEM;
    379		goto flush;
    380	}
    381
    382	skb_put_u8(*skb, len);
    383
    384	r = i2c_master_recv(client, skb_put(*skb, len), len);
    385	if (r != len) {
    386		kfree_skb(*skb);
    387		return -EREMOTEIO;
    388	}
    389
    390	I2C_DUMP_SKB("i2c frame read", *skb);
    391
    392	r = check_crc((*skb)->data, (*skb)->len);
    393	if (r != 0) {
    394		kfree_skb(*skb);
    395		r = -EBADMSG;
    396		goto flush;
    397	}
    398
    399	skb_pull(*skb, 1);
    400	skb_trim(*skb, (*skb)->len - 2);
    401
    402	usleep_range(3000, 6000);
    403
    404	return 0;
    405
    406flush:
    407	if (i2c_master_recv(client, tmp, sizeof(tmp)) < 0)
    408		r = -EREMOTEIO;
    409
    410	usleep_range(3000, 6000);
    411
    412	return r;
    413}
    414
    415static int pn544_hci_i2c_fw_read_status(struct pn544_i2c_phy *phy)
    416{
    417	int r;
    418	struct pn544_i2c_fw_frame_response response;
    419	struct i2c_client *client = phy->i2c_dev;
    420
    421	r = i2c_master_recv(client, (char *) &response, sizeof(response));
    422	if (r != sizeof(response)) {
    423		nfc_err(&client->dev, "cannot read fw status\n");
    424		return -EIO;
    425	}
    426
    427	usleep_range(3000, 6000);
    428
    429	switch (response.status) {
    430	case 0:
    431		return 0;
    432	case PN544_FW_CMD_RESULT_CHUNK_OK:
    433		return response.status;
    434	case PN544_FW_CMD_RESULT_TIMEOUT:
    435		return -ETIMEDOUT;
    436	case PN544_FW_CMD_RESULT_BAD_CRC:
    437		return -ENODATA;
    438	case PN544_FW_CMD_RESULT_ACCESS_DENIED:
    439		return -EACCES;
    440	case PN544_FW_CMD_RESULT_PROTOCOL_ERROR:
    441		return -EPROTO;
    442	case PN544_FW_CMD_RESULT_INVALID_PARAMETER:
    443		return -EINVAL;
    444	case PN544_FW_CMD_RESULT_UNSUPPORTED_COMMAND:
    445		return -ENOTSUPP;
    446	case PN544_FW_CMD_RESULT_INVALID_LENGTH:
    447		return -EBADMSG;
    448	case PN544_FW_CMD_RESULT_CRYPTOGRAPHIC_ERROR:
    449		return -ENOKEY;
    450	case PN544_FW_CMD_RESULT_VERSION_CONDITIONS_ERROR:
    451		return -EINVAL;
    452	case PN544_FW_CMD_RESULT_MEMORY_ERROR:
    453		return -ENOMEM;
    454	case PN544_FW_CMD_RESULT_COMMAND_REJECTED:
    455		return -EACCES;
    456	case PN544_FW_CMD_RESULT_WRITE_FAILED:
    457	case PN544_FW_CMD_RESULT_CHUNK_ERROR:
    458		return -EIO;
    459	default:
    460		return -EIO;
    461	}
    462}
    463
    464/*
    465 * Reads an shdlc frame from the chip. This is not as straightforward as it
    466 * seems. There are cases where we could loose the frame start synchronization.
    467 * The frame format is len-data-crc, and corruption can occur anywhere while
    468 * transiting on i2c bus, such that we could read an invalid len.
    469 * In order to recover synchronization with the next frame, we must be sure
    470 * to read the real amount of data without using the len byte. We do this by
    471 * assuming the following:
    472 * - the chip will always present only one single complete frame on the bus
    473 *   before triggering the interrupt
    474 * - the chip will not present a new frame until we have completely read
    475 *   the previous one (or until we have handled the interrupt).
    476 * The tricky case is when we read a corrupted len that is less than the real
    477 * len. We must detect this here in order to determine that we need to flush
    478 * the bus. This is the reason why we check the crc here.
    479 */
    480static irqreturn_t pn544_hci_i2c_irq_thread_fn(int irq, void *phy_id)
    481{
    482	struct pn544_i2c_phy *phy = phy_id;
    483	struct i2c_client *client;
    484	struct sk_buff *skb = NULL;
    485	int r;
    486
    487	if (!phy || irq != phy->i2c_dev->irq) {
    488		WARN_ON_ONCE(1);
    489		return IRQ_NONE;
    490	}
    491
    492	client = phy->i2c_dev;
    493	dev_dbg(&client->dev, "IRQ\n");
    494
    495	if (phy->hard_fault != 0)
    496		return IRQ_HANDLED;
    497
    498	if (phy->run_mode == PN544_FW_MODE) {
    499		phy->fw_cmd_result = pn544_hci_i2c_fw_read_status(phy);
    500		schedule_work(&phy->fw_work);
    501	} else {
    502		r = pn544_hci_i2c_read(phy, &skb);
    503		if (r == -EREMOTEIO) {
    504			phy->hard_fault = r;
    505
    506			nfc_hci_recv_frame(phy->hdev, NULL);
    507
    508			return IRQ_HANDLED;
    509		} else if ((r == -ENOMEM) || (r == -EBADMSG)) {
    510			return IRQ_HANDLED;
    511		}
    512
    513		nfc_hci_recv_frame(phy->hdev, skb);
    514	}
    515	return IRQ_HANDLED;
    516}
    517
    518static const struct nfc_phy_ops i2c_phy_ops = {
    519	.write = pn544_hci_i2c_write,
    520	.enable = pn544_hci_i2c_enable,
    521	.disable = pn544_hci_i2c_disable,
    522};
    523
    524static int pn544_hci_i2c_fw_download(void *phy_id, const char *firmware_name,
    525					u8 hw_variant)
    526{
    527	struct pn544_i2c_phy *phy = phy_id;
    528
    529	pr_info("Starting Firmware Download (%s)\n", firmware_name);
    530
    531	strcpy(phy->firmware_name, firmware_name);
    532
    533	phy->hw_variant = hw_variant;
    534	phy->fw_work_state = FW_WORK_STATE_START;
    535
    536	schedule_work(&phy->fw_work);
    537
    538	return 0;
    539}
    540
    541static void pn544_hci_i2c_fw_work_complete(struct pn544_i2c_phy *phy,
    542					   int result)
    543{
    544	pr_info("Firmware Download Complete, result=%d\n", result);
    545
    546	pn544_hci_i2c_disable(phy);
    547
    548	phy->fw_work_state = FW_WORK_STATE_IDLE;
    549
    550	if (phy->fw) {
    551		release_firmware(phy->fw);
    552		phy->fw = NULL;
    553	}
    554
    555	nfc_fw_download_done(phy->hdev->ndev, phy->firmware_name, (u32) -result);
    556}
    557
    558static int pn544_hci_i2c_fw_write_cmd(struct i2c_client *client, u32 dest_addr,
    559				      const u8 *data, u16 datalen)
    560{
    561	u8 frame[PN544_FW_I2C_MAX_PAYLOAD];
    562	struct pn544_i2c_fw_frame_write *framep;
    563	u16 params_len;
    564	int framelen;
    565	int r;
    566
    567	if (datalen > PN544_FW_I2C_WRITE_DATA_MAX_LEN)
    568		datalen = PN544_FW_I2C_WRITE_DATA_MAX_LEN;
    569
    570	framep = (struct pn544_i2c_fw_frame_write *) frame;
    571
    572	params_len = sizeof(framep->be_dest_addr) +
    573		     sizeof(framep->be_datalen) + datalen;
    574	framelen = params_len + sizeof(framep->cmd) +
    575			     sizeof(framep->be_length);
    576
    577	framep->cmd = PN544_FW_CMD_WRITE;
    578
    579	put_unaligned_be16(params_len, &framep->be_length);
    580
    581	framep->be_dest_addr[0] = (dest_addr & 0xff0000) >> 16;
    582	framep->be_dest_addr[1] = (dest_addr & 0xff00) >> 8;
    583	framep->be_dest_addr[2] = dest_addr & 0xff;
    584
    585	put_unaligned_be16(datalen, &framep->be_datalen);
    586
    587	memcpy(framep->data, data, datalen);
    588
    589	r = i2c_master_send(client, frame, framelen);
    590
    591	if (r == framelen)
    592		return datalen;
    593	else if (r < 0)
    594		return r;
    595	else
    596		return -EIO;
    597}
    598
    599static int pn544_hci_i2c_fw_check_cmd(struct i2c_client *client, u32 start_addr,
    600				      const u8 *data, u16 datalen)
    601{
    602	struct pn544_i2c_fw_frame_check frame;
    603	int r;
    604	u16 crc;
    605
    606	/* calculate local crc for the data we want to check */
    607	crc = crc_ccitt(0xffff, data, datalen);
    608
    609	frame.cmd = PN544_FW_CMD_CHECK;
    610
    611	put_unaligned_be16(sizeof(frame.be_start_addr) +
    612			   sizeof(frame.be_datalen) + sizeof(frame.be_crc),
    613			   &frame.be_length);
    614
    615	/* tell the chip the memory region to which our crc applies */
    616	frame.be_start_addr[0] = (start_addr & 0xff0000) >> 16;
    617	frame.be_start_addr[1] = (start_addr & 0xff00) >> 8;
    618	frame.be_start_addr[2] = start_addr & 0xff;
    619
    620	put_unaligned_be16(datalen, &frame.be_datalen);
    621
    622	/*
    623	 * and give our local crc. Chip will calculate its own crc for the
    624	 * region and compare with ours.
    625	 */
    626	put_unaligned_be16(crc, &frame.be_crc);
    627
    628	r = i2c_master_send(client, (const char *) &frame, sizeof(frame));
    629
    630	if (r == sizeof(frame))
    631		return 0;
    632	else if (r < 0)
    633		return r;
    634	else
    635		return -EIO;
    636}
    637
    638static int pn544_hci_i2c_fw_write_chunk(struct pn544_i2c_phy *phy)
    639{
    640	int r;
    641
    642	r = pn544_hci_i2c_fw_write_cmd(phy->i2c_dev,
    643				       phy->fw_blob_dest_addr + phy->fw_written,
    644				       phy->fw_blob_data + phy->fw_written,
    645				       phy->fw_blob_size - phy->fw_written);
    646	if (r < 0)
    647		return r;
    648
    649	phy->fw_written += r;
    650	phy->fw_work_state = FW_WORK_STATE_WAIT_WRITE_ANSWER;
    651
    652	return 0;
    653}
    654
    655static int pn544_hci_i2c_fw_secure_write_frame_cmd(struct pn544_i2c_phy *phy,
    656					const u8 *data, u16 datalen)
    657{
    658	u8 buf[PN544_FW_I2C_MAX_PAYLOAD];
    659	struct pn544_i2c_fw_secure_frame *chunk;
    660	int chunklen;
    661	int r;
    662
    663	if (datalen > PN544_FW_SECURE_CHUNK_WRITE_DATA_MAX_LEN)
    664		datalen = PN544_FW_SECURE_CHUNK_WRITE_DATA_MAX_LEN;
    665
    666	chunk = (struct pn544_i2c_fw_secure_frame *) buf;
    667
    668	chunk->cmd = PN544_FW_CMD_SECURE_CHUNK_WRITE;
    669
    670	put_unaligned_be16(datalen, &chunk->be_datalen);
    671
    672	memcpy(chunk->data, data, datalen);
    673
    674	chunklen = sizeof(chunk->cmd) + sizeof(chunk->be_datalen) + datalen;
    675
    676	r = i2c_master_send(phy->i2c_dev, buf, chunklen);
    677
    678	if (r == chunklen)
    679		return datalen;
    680	else if (r < 0)
    681		return r;
    682	else
    683		return -EIO;
    684
    685}
    686
    687static int pn544_hci_i2c_fw_secure_write_frame(struct pn544_i2c_phy *phy)
    688{
    689	struct pn544_i2c_fw_secure_frame *framep;
    690	int r;
    691
    692	framep = (struct pn544_i2c_fw_secure_frame *) phy->fw_blob_data;
    693	if (phy->fw_written == 0)
    694		phy->fw_blob_size = get_unaligned_be16(&framep->be_datalen)
    695				+ PN544_FW_SECURE_FRAME_HEADER_LEN;
    696
    697	/* Only secure write command can be chunked*/
    698	if (phy->fw_blob_size > PN544_FW_I2C_MAX_PAYLOAD &&
    699			framep->cmd != PN544_FW_CMD_SECURE_WRITE)
    700		return -EINVAL;
    701
    702	/* The firmware also have other commands, we just send them directly */
    703	if (phy->fw_blob_size < PN544_FW_I2C_MAX_PAYLOAD) {
    704		r = i2c_master_send(phy->i2c_dev,
    705			(const char *) phy->fw_blob_data, phy->fw_blob_size);
    706
    707		if (r == phy->fw_blob_size)
    708			goto exit;
    709		else if (r < 0)
    710			return r;
    711		else
    712			return -EIO;
    713	}
    714
    715	r = pn544_hci_i2c_fw_secure_write_frame_cmd(phy,
    716				       phy->fw_blob_data + phy->fw_written,
    717				       phy->fw_blob_size - phy->fw_written);
    718	if (r < 0)
    719		return r;
    720
    721exit:
    722	phy->fw_written += r;
    723	phy->fw_work_state = FW_WORK_STATE_WAIT_SECURE_WRITE_ANSWER;
    724
    725	/* SW reset command will not trig any response from PN544 */
    726	if (framep->cmd == PN544_FW_CMD_RESET) {
    727		pn544_hci_i2c_enable_mode(phy, PN544_FW_MODE);
    728		phy->fw_cmd_result = 0;
    729		schedule_work(&phy->fw_work);
    730	}
    731
    732	return 0;
    733}
    734
    735static void pn544_hci_i2c_fw_work(struct work_struct *work)
    736{
    737	struct pn544_i2c_phy *phy = container_of(work, struct pn544_i2c_phy,
    738						fw_work);
    739	int r;
    740	struct pn544_i2c_fw_blob *blob;
    741	struct pn544_i2c_fw_secure_blob *secure_blob;
    742
    743	switch (phy->fw_work_state) {
    744	case FW_WORK_STATE_START:
    745		pn544_hci_i2c_enable_mode(phy, PN544_FW_MODE);
    746
    747		r = request_firmware(&phy->fw, phy->firmware_name,
    748				     &phy->i2c_dev->dev);
    749		if (r < 0)
    750			goto exit_state_start;
    751
    752		phy->fw_written = 0;
    753
    754		switch (phy->hw_variant) {
    755		case PN544_HW_VARIANT_C2:
    756			blob = (struct pn544_i2c_fw_blob *) phy->fw->data;
    757			phy->fw_blob_size = get_unaligned_be32(&blob->be_size);
    758			phy->fw_blob_dest_addr = get_unaligned_be32(
    759							&blob->be_destaddr);
    760			phy->fw_blob_data = blob->data;
    761
    762			r = pn544_hci_i2c_fw_write_chunk(phy);
    763			break;
    764		case PN544_HW_VARIANT_C3:
    765			secure_blob = (struct pn544_i2c_fw_secure_blob *)
    766								phy->fw->data;
    767			phy->fw_blob_data = secure_blob->data;
    768			phy->fw_size = phy->fw->size;
    769			r = pn544_hci_i2c_fw_secure_write_frame(phy);
    770			break;
    771		default:
    772			r = -ENOTSUPP;
    773			break;
    774		}
    775
    776exit_state_start:
    777		if (r < 0)
    778			pn544_hci_i2c_fw_work_complete(phy, r);
    779		break;
    780
    781	case FW_WORK_STATE_WAIT_WRITE_ANSWER:
    782		r = phy->fw_cmd_result;
    783		if (r < 0)
    784			goto exit_state_wait_write_answer;
    785
    786		if (phy->fw_written == phy->fw_blob_size) {
    787			r = pn544_hci_i2c_fw_check_cmd(phy->i2c_dev,
    788						       phy->fw_blob_dest_addr,
    789						       phy->fw_blob_data,
    790						       phy->fw_blob_size);
    791			if (r < 0)
    792				goto exit_state_wait_write_answer;
    793			phy->fw_work_state = FW_WORK_STATE_WAIT_CHECK_ANSWER;
    794			break;
    795		}
    796
    797		r = pn544_hci_i2c_fw_write_chunk(phy);
    798
    799exit_state_wait_write_answer:
    800		if (r < 0)
    801			pn544_hci_i2c_fw_work_complete(phy, r);
    802		break;
    803
    804	case FW_WORK_STATE_WAIT_CHECK_ANSWER:
    805		r = phy->fw_cmd_result;
    806		if (r < 0)
    807			goto exit_state_wait_check_answer;
    808
    809		blob = (struct pn544_i2c_fw_blob *) (phy->fw_blob_data +
    810		       phy->fw_blob_size);
    811		phy->fw_blob_size = get_unaligned_be32(&blob->be_size);
    812		if (phy->fw_blob_size != 0) {
    813			phy->fw_blob_dest_addr =
    814					get_unaligned_be32(&blob->be_destaddr);
    815			phy->fw_blob_data = blob->data;
    816
    817			phy->fw_written = 0;
    818			r = pn544_hci_i2c_fw_write_chunk(phy);
    819		}
    820
    821exit_state_wait_check_answer:
    822		if (r < 0 || phy->fw_blob_size == 0)
    823			pn544_hci_i2c_fw_work_complete(phy, r);
    824		break;
    825
    826	case FW_WORK_STATE_WAIT_SECURE_WRITE_ANSWER:
    827		r = phy->fw_cmd_result;
    828		if (r < 0)
    829			goto exit_state_wait_secure_write_answer;
    830
    831		if (r == PN544_FW_CMD_RESULT_CHUNK_OK) {
    832			r = pn544_hci_i2c_fw_secure_write_frame(phy);
    833			goto exit_state_wait_secure_write_answer;
    834		}
    835
    836		if (phy->fw_written == phy->fw_blob_size) {
    837			secure_blob = (struct pn544_i2c_fw_secure_blob *)
    838				(phy->fw_blob_data + phy->fw_blob_size);
    839			phy->fw_size -= phy->fw_blob_size +
    840				PN544_FW_SECURE_BLOB_HEADER_LEN;
    841			if (phy->fw_size >= PN544_FW_SECURE_BLOB_HEADER_LEN
    842					+ PN544_FW_SECURE_FRAME_HEADER_LEN) {
    843				phy->fw_blob_data = secure_blob->data;
    844
    845				phy->fw_written = 0;
    846				r = pn544_hci_i2c_fw_secure_write_frame(phy);
    847			}
    848		}
    849
    850exit_state_wait_secure_write_answer:
    851		if (r < 0 || phy->fw_size == 0)
    852			pn544_hci_i2c_fw_work_complete(phy, r);
    853		break;
    854
    855	default:
    856		break;
    857	}
    858}
    859
    860static const struct acpi_gpio_params enable_gpios = { 1, 0, false };
    861static const struct acpi_gpio_params firmware_gpios = { 2, 0, false };
    862
    863static const struct acpi_gpio_mapping acpi_pn544_gpios[] = {
    864	{ "enable-gpios", &enable_gpios, 1 },
    865	{ "firmware-gpios", &firmware_gpios, 1 },
    866	{ },
    867};
    868
    869static int pn544_hci_i2c_probe(struct i2c_client *client,
    870			       const struct i2c_device_id *id)
    871{
    872	struct device *dev = &client->dev;
    873	struct pn544_i2c_phy *phy;
    874	int r = 0;
    875
    876	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
    877		nfc_err(&client->dev, "Need I2C_FUNC_I2C\n");
    878		return -ENODEV;
    879	}
    880
    881	phy = devm_kzalloc(&client->dev, sizeof(struct pn544_i2c_phy),
    882			   GFP_KERNEL);
    883	if (!phy)
    884		return -ENOMEM;
    885
    886	INIT_WORK(&phy->fw_work, pn544_hci_i2c_fw_work);
    887	phy->fw_work_state = FW_WORK_STATE_IDLE;
    888
    889	phy->i2c_dev = client;
    890	i2c_set_clientdata(client, phy);
    891
    892	r = devm_acpi_dev_add_driver_gpios(dev, acpi_pn544_gpios);
    893	if (r)
    894		dev_dbg(dev, "Unable to add GPIO mapping table\n");
    895
    896	/* Get EN GPIO */
    897	phy->gpiod_en = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
    898	if (IS_ERR(phy->gpiod_en)) {
    899		nfc_err(dev, "Unable to get EN GPIO\n");
    900		return PTR_ERR(phy->gpiod_en);
    901	}
    902
    903	/* Get FW GPIO */
    904	phy->gpiod_fw = devm_gpiod_get(dev, "firmware", GPIOD_OUT_LOW);
    905	if (IS_ERR(phy->gpiod_fw)) {
    906		nfc_err(dev, "Unable to get FW GPIO\n");
    907		return PTR_ERR(phy->gpiod_fw);
    908	}
    909
    910	pn544_hci_i2c_platform_init(phy);
    911
    912	r = devm_request_threaded_irq(&client->dev, client->irq, NULL,
    913				      pn544_hci_i2c_irq_thread_fn,
    914				      IRQF_TRIGGER_RISING | IRQF_ONESHOT,
    915				      PN544_HCI_I2C_DRIVER_NAME, phy);
    916	if (r < 0) {
    917		nfc_err(&client->dev, "Unable to register IRQ handler\n");
    918		return r;
    919	}
    920
    921	r = pn544_hci_probe(phy, &i2c_phy_ops, LLC_SHDLC_NAME,
    922			    PN544_I2C_FRAME_HEADROOM, PN544_I2C_FRAME_TAILROOM,
    923			    PN544_HCI_I2C_LLC_MAX_PAYLOAD,
    924			    pn544_hci_i2c_fw_download, &phy->hdev);
    925	if (r < 0)
    926		return r;
    927
    928	return 0;
    929}
    930
    931static int pn544_hci_i2c_remove(struct i2c_client *client)
    932{
    933	struct pn544_i2c_phy *phy = i2c_get_clientdata(client);
    934
    935	cancel_work_sync(&phy->fw_work);
    936	if (phy->fw_work_state != FW_WORK_STATE_IDLE)
    937		pn544_hci_i2c_fw_work_complete(phy, -ENODEV);
    938
    939	pn544_hci_remove(phy->hdev);
    940
    941	if (phy->powered)
    942		pn544_hci_i2c_disable(phy);
    943
    944	return 0;
    945}
    946
    947static const struct of_device_id of_pn544_i2c_match[] __maybe_unused = {
    948	{ .compatible = "nxp,pn544-i2c", },
    949	{},
    950};
    951MODULE_DEVICE_TABLE(of, of_pn544_i2c_match);
    952
    953static struct i2c_driver pn544_hci_i2c_driver = {
    954	.driver = {
    955		   .name = PN544_HCI_I2C_DRIVER_NAME,
    956		   .of_match_table = of_match_ptr(of_pn544_i2c_match),
    957		   .acpi_match_table = ACPI_PTR(pn544_hci_i2c_acpi_match),
    958		  },
    959	.probe = pn544_hci_i2c_probe,
    960	.id_table = pn544_hci_i2c_id_table,
    961	.remove = pn544_hci_i2c_remove,
    962};
    963
    964module_i2c_driver(pn544_hci_i2c_driver);
    965
    966MODULE_LICENSE("GPL");
    967MODULE_DESCRIPTION(DRIVER_DESC);