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v6.8
   1/*
   2 *   Copyright (c) 2011, 2012, Qualcomm Atheros Communications Inc.
   3 *   Copyright (c) 2014, I2SE GmbH
   4 *
   5 *   Permission to use, copy, modify, and/or distribute this software
   6 *   for any purpose with or without fee is hereby granted, provided
   7 *   that the above copyright notice and this permission notice appear
   8 *   in all copies.
   9 *
  10 *   THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
  11 *   WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
  12 *   WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
  13 *   THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
  14 *   CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  15 *   LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
  16 *   NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
  17 *   CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18 */
  19
  20/*   This module implements the Qualcomm Atheros SPI protocol for
  21 *   kernel-based SPI device; it is essentially an Ethernet-to-SPI
  22 *   serial converter;
  23 */
  24
  25#include <linux/errno.h>
  26#include <linux/etherdevice.h>
  27#include <linux/if_arp.h>
  28#include <linux/if_ether.h>
  29#include <linux/init.h>
  30#include <linux/interrupt.h>
  31#include <linux/jiffies.h>
  32#include <linux/kernel.h>
  33#include <linux/kthread.h>
  34#include <linux/module.h>
  35#include <linux/moduleparam.h>
  36#include <linux/netdevice.h>
  37#include <linux/of.h>
 
  38#include <linux/of_net.h>
  39#include <linux/sched.h>
  40#include <linux/skbuff.h>
  41#include <linux/spi/spi.h>
  42#include <linux/types.h>
  43
  44#include "qca_7k.h"
  45#include "qca_7k_common.h"
  46#include "qca_debug.h"
  47#include "qca_spi.h"
  48
  49#define MAX_DMA_BURST_LEN 5000
  50
  51/*   Modules parameters     */
  52#define QCASPI_CLK_SPEED_MIN 1000000
  53#define QCASPI_CLK_SPEED_MAX 16000000
  54#define QCASPI_CLK_SPEED     8000000
  55static int qcaspi_clkspeed;
  56module_param(qcaspi_clkspeed, int, 0);
  57MODULE_PARM_DESC(qcaspi_clkspeed, "SPI bus clock speed (Hz). Use 1000000-16000000.");
  58
  59#define QCASPI_BURST_LEN_MIN 1
  60#define QCASPI_BURST_LEN_MAX MAX_DMA_BURST_LEN
  61static int qcaspi_burst_len = MAX_DMA_BURST_LEN;
  62module_param(qcaspi_burst_len, int, 0);
  63MODULE_PARM_DESC(qcaspi_burst_len, "Number of data bytes per burst. Use 1-5000.");
  64
  65#define QCASPI_PLUGGABLE_MIN 0
  66#define QCASPI_PLUGGABLE_MAX 1
  67static int qcaspi_pluggable = QCASPI_PLUGGABLE_MIN;
  68module_param(qcaspi_pluggable, int, 0);
  69MODULE_PARM_DESC(qcaspi_pluggable, "Pluggable SPI connection (yes/no).");
  70
  71#define QCASPI_WRITE_VERIFY_MIN 0
  72#define QCASPI_WRITE_VERIFY_MAX 3
  73static int wr_verify = QCASPI_WRITE_VERIFY_MIN;
  74module_param(wr_verify, int, 0);
  75MODULE_PARM_DESC(wr_verify, "SPI register write verify trails. Use 0-3.");
  76
  77#define QCASPI_TX_TIMEOUT (1 * HZ)
  78#define QCASPI_QCA7K_REBOOT_TIME_MS 1000
  79
  80static void
  81start_spi_intr_handling(struct qcaspi *qca, u16 *intr_cause)
  82{
  83	*intr_cause = 0;
  84
  85	qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, 0, wr_verify);
  86	qcaspi_read_register(qca, SPI_REG_INTR_CAUSE, intr_cause);
  87	netdev_dbg(qca->net_dev, "interrupts: 0x%04x\n", *intr_cause);
  88}
  89
  90static void
  91end_spi_intr_handling(struct qcaspi *qca, u16 intr_cause)
  92{
  93	u16 intr_enable = (SPI_INT_CPU_ON |
  94			   SPI_INT_PKT_AVLBL |
  95			   SPI_INT_RDBUF_ERR |
  96			   SPI_INT_WRBUF_ERR);
  97
  98	qcaspi_write_register(qca, SPI_REG_INTR_CAUSE, intr_cause, 0);
  99	qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, intr_enable, wr_verify);
 100	netdev_dbg(qca->net_dev, "acking int: 0x%04x\n", intr_cause);
 101}
 102
 103static u32
 104qcaspi_write_burst(struct qcaspi *qca, u8 *src, u32 len)
 105{
 106	__be16 cmd;
 107	struct spi_message msg;
 108	struct spi_transfer transfer[2];
 109	int ret;
 110
 111	memset(&transfer, 0, sizeof(transfer));
 112	spi_message_init(&msg);
 113
 114	cmd = cpu_to_be16(QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL);
 115	transfer[0].tx_buf = &cmd;
 116	transfer[0].len = QCASPI_CMD_LEN;
 117	transfer[1].tx_buf = src;
 118	transfer[1].len = len;
 119
 120	spi_message_add_tail(&transfer[0], &msg);
 121	spi_message_add_tail(&transfer[1], &msg);
 122	ret = spi_sync(qca->spi_dev, &msg);
 123
 124	if (ret || (msg.actual_length != QCASPI_CMD_LEN + len)) {
 125		qcaspi_spi_error(qca);
 126		return 0;
 127	}
 128
 129	return len;
 130}
 131
 132static u32
 133qcaspi_write_legacy(struct qcaspi *qca, u8 *src, u32 len)
 134{
 135	struct spi_message msg;
 136	struct spi_transfer transfer;
 137	int ret;
 138
 139	memset(&transfer, 0, sizeof(transfer));
 140	spi_message_init(&msg);
 141
 142	transfer.tx_buf = src;
 143	transfer.len = len;
 144
 145	spi_message_add_tail(&transfer, &msg);
 146	ret = spi_sync(qca->spi_dev, &msg);
 147
 148	if (ret || (msg.actual_length != len)) {
 149		qcaspi_spi_error(qca);
 150		return 0;
 151	}
 152
 153	return len;
 154}
 155
 156static u32
 157qcaspi_read_burst(struct qcaspi *qca, u8 *dst, u32 len)
 158{
 159	struct spi_message msg;
 160	__be16 cmd;
 161	struct spi_transfer transfer[2];
 162	int ret;
 163
 164	memset(&transfer, 0, sizeof(transfer));
 165	spi_message_init(&msg);
 166
 167	cmd = cpu_to_be16(QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL);
 168	transfer[0].tx_buf = &cmd;
 169	transfer[0].len = QCASPI_CMD_LEN;
 170	transfer[1].rx_buf = dst;
 171	transfer[1].len = len;
 172
 173	spi_message_add_tail(&transfer[0], &msg);
 174	spi_message_add_tail(&transfer[1], &msg);
 175	ret = spi_sync(qca->spi_dev, &msg);
 176
 177	if (ret || (msg.actual_length != QCASPI_CMD_LEN + len)) {
 178		qcaspi_spi_error(qca);
 179		return 0;
 180	}
 181
 182	return len;
 183}
 184
 185static u32
 186qcaspi_read_legacy(struct qcaspi *qca, u8 *dst, u32 len)
 187{
 188	struct spi_message msg;
 189	struct spi_transfer transfer;
 190	int ret;
 191
 192	memset(&transfer, 0, sizeof(transfer));
 193	spi_message_init(&msg);
 194
 195	transfer.rx_buf = dst;
 196	transfer.len = len;
 197
 198	spi_message_add_tail(&transfer, &msg);
 199	ret = spi_sync(qca->spi_dev, &msg);
 200
 201	if (ret || (msg.actual_length != len)) {
 202		qcaspi_spi_error(qca);
 203		return 0;
 204	}
 205
 206	return len;
 207}
 208
 209static int
 210qcaspi_tx_cmd(struct qcaspi *qca, u16 cmd)
 211{
 212	__be16 tx_data;
 213	struct spi_message msg;
 214	struct spi_transfer transfer;
 215	int ret;
 216
 217	memset(&transfer, 0, sizeof(transfer));
 218
 219	spi_message_init(&msg);
 220
 221	tx_data = cpu_to_be16(cmd);
 222	transfer.len = sizeof(cmd);
 223	transfer.tx_buf = &tx_data;
 224	spi_message_add_tail(&transfer, &msg);
 225
 226	ret = spi_sync(qca->spi_dev, &msg);
 227
 228	if (!ret)
 229		ret = msg.status;
 230
 231	if (ret)
 232		qcaspi_spi_error(qca);
 233
 234	return ret;
 235}
 236
 237static int
 238qcaspi_tx_frame(struct qcaspi *qca, struct sk_buff *skb)
 239{
 240	u32 count;
 241	u32 written;
 242	u32 offset;
 243	u32 len;
 244
 245	len = skb->len;
 246
 247	qcaspi_write_register(qca, SPI_REG_BFR_SIZE, len, wr_verify);
 248	if (qca->legacy_mode)
 249		qcaspi_tx_cmd(qca, QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL);
 250
 251	offset = 0;
 252	while (len) {
 253		count = len;
 254		if (count > qca->burst_len)
 255			count = qca->burst_len;
 256
 257		if (qca->legacy_mode) {
 258			written = qcaspi_write_legacy(qca,
 259						      skb->data + offset,
 260						      count);
 261		} else {
 262			written = qcaspi_write_burst(qca,
 263						     skb->data + offset,
 264						     count);
 265		}
 266
 267		if (written != count)
 268			return -1;
 269
 270		offset += count;
 271		len -= count;
 272	}
 273
 274	return 0;
 275}
 276
 277static int
 278qcaspi_transmit(struct qcaspi *qca)
 279{
 280	struct net_device_stats *n_stats = &qca->net_dev->stats;
 281	u16 available = 0;
 282	u32 pkt_len;
 283	u16 new_head;
 284	u16 packets = 0;
 285
 286	if (qca->txr.skb[qca->txr.head] == NULL)
 287		return 0;
 288
 289	qcaspi_read_register(qca, SPI_REG_WRBUF_SPC_AVA, &available);
 290
 291	if (available > QCASPI_HW_BUF_LEN) {
 292		/* This could only happen by interferences on the SPI line.
 293		 * So retry later ...
 294		 */
 295		qca->stats.buf_avail_err++;
 296		return -1;
 297	}
 298
 299	while (qca->txr.skb[qca->txr.head]) {
 300		pkt_len = qca->txr.skb[qca->txr.head]->len + QCASPI_HW_PKT_LEN;
 301
 302		if (available < pkt_len) {
 303			if (packets == 0)
 304				qca->stats.write_buf_miss++;
 305			break;
 306		}
 307
 308		if (qcaspi_tx_frame(qca, qca->txr.skb[qca->txr.head]) == -1) {
 309			qca->stats.write_err++;
 310			return -1;
 311		}
 312
 313		packets++;
 314		n_stats->tx_packets++;
 315		n_stats->tx_bytes += qca->txr.skb[qca->txr.head]->len;
 316		available -= pkt_len;
 317
 318		/* remove the skb from the queue */
 319		/* XXX After inconsistent lock states netif_tx_lock()
 320		 * has been replaced by netif_tx_lock_bh() and so on.
 321		 */
 322		netif_tx_lock_bh(qca->net_dev);
 323		dev_kfree_skb(qca->txr.skb[qca->txr.head]);
 324		qca->txr.skb[qca->txr.head] = NULL;
 325		qca->txr.size -= pkt_len;
 326		new_head = qca->txr.head + 1;
 327		if (new_head >= qca->txr.count)
 328			new_head = 0;
 329		qca->txr.head = new_head;
 330		if (netif_queue_stopped(qca->net_dev))
 331			netif_wake_queue(qca->net_dev);
 332		netif_tx_unlock_bh(qca->net_dev);
 333	}
 334
 335	return 0;
 336}
 337
 338static int
 339qcaspi_receive(struct qcaspi *qca)
 340{
 341	struct net_device *net_dev = qca->net_dev;
 342	struct net_device_stats *n_stats = &net_dev->stats;
 343	u16 available = 0;
 344	u32 bytes_read;
 345	u8 *cp;
 346
 347	/* Allocate rx SKB if we don't have one available. */
 348	if (!qca->rx_skb) {
 349		qca->rx_skb = netdev_alloc_skb_ip_align(net_dev,
 350							net_dev->mtu +
 351							VLAN_ETH_HLEN);
 352		if (!qca->rx_skb) {
 353			netdev_dbg(net_dev, "out of RX resources\n");
 354			qca->stats.out_of_mem++;
 355			return -1;
 356		}
 357	}
 358
 359	/* Read the packet size. */
 360	qcaspi_read_register(qca, SPI_REG_RDBUF_BYTE_AVA, &available);
 361
 362	netdev_dbg(net_dev, "qcaspi_receive: SPI_REG_RDBUF_BYTE_AVA: Value: %08x\n",
 363		   available);
 364
 365	if (available > QCASPI_HW_BUF_LEN + QCASPI_HW_PKT_LEN) {
 366		/* This could only happen by interferences on the SPI line.
 367		 * So retry later ...
 368		 */
 369		qca->stats.buf_avail_err++;
 370		return -1;
 371	} else if (available == 0) {
 372		netdev_dbg(net_dev, "qcaspi_receive called without any data being available!\n");
 373		return -1;
 374	}
 375
 376	qcaspi_write_register(qca, SPI_REG_BFR_SIZE, available, wr_verify);
 377
 378	if (qca->legacy_mode)
 379		qcaspi_tx_cmd(qca, QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL);
 380
 381	while (available) {
 382		u32 count = available;
 383
 384		if (count > qca->burst_len)
 385			count = qca->burst_len;
 386
 387		if (qca->legacy_mode) {
 388			bytes_read = qcaspi_read_legacy(qca, qca->rx_buffer,
 389							count);
 390		} else {
 391			bytes_read = qcaspi_read_burst(qca, qca->rx_buffer,
 392						       count);
 393		}
 394
 395		netdev_dbg(net_dev, "available: %d, byte read: %d\n",
 396			   available, bytes_read);
 397
 398		if (bytes_read) {
 399			available -= bytes_read;
 400		} else {
 401			qca->stats.read_err++;
 402			return -1;
 403		}
 404
 405		cp = qca->rx_buffer;
 406
 407		while ((bytes_read--) && (qca->rx_skb)) {
 408			s32 retcode;
 409
 410			retcode = qcafrm_fsm_decode(&qca->frm_handle,
 411						    qca->rx_skb->data,
 412						    skb_tailroom(qca->rx_skb),
 413						    *cp);
 414			cp++;
 415			switch (retcode) {
 416			case QCAFRM_GATHER:
 417			case QCAFRM_NOHEAD:
 418				break;
 419			case QCAFRM_NOTAIL:
 420				netdev_dbg(net_dev, "no RX tail\n");
 421				n_stats->rx_errors++;
 422				n_stats->rx_dropped++;
 423				break;
 424			case QCAFRM_INVLEN:
 425				netdev_dbg(net_dev, "invalid RX length\n");
 426				n_stats->rx_errors++;
 427				n_stats->rx_dropped++;
 428				break;
 429			default:
 430				qca->rx_skb->dev = qca->net_dev;
 431				n_stats->rx_packets++;
 432				n_stats->rx_bytes += retcode;
 433				skb_put(qca->rx_skb, retcode);
 434				qca->rx_skb->protocol = eth_type_trans(
 435					qca->rx_skb, qca->rx_skb->dev);
 436				skb_checksum_none_assert(qca->rx_skb);
 437				netif_rx(qca->rx_skb);
 438				qca->rx_skb = netdev_alloc_skb_ip_align(net_dev,
 439					net_dev->mtu + VLAN_ETH_HLEN);
 440				if (!qca->rx_skb) {
 441					netdev_dbg(net_dev, "out of RX resources\n");
 442					n_stats->rx_errors++;
 443					qca->stats.out_of_mem++;
 444					break;
 445				}
 446			}
 447		}
 448	}
 449
 450	return 0;
 451}
 452
 453/*   Check that tx ring stores only so much bytes
 454 *   that fit into the internal QCA buffer.
 455 */
 456
 457static int
 458qcaspi_tx_ring_has_space(struct tx_ring *txr)
 459{
 460	if (txr->skb[txr->tail])
 461		return 0;
 462
 463	return (txr->size + QCAFRM_MAX_LEN < QCASPI_HW_BUF_LEN) ? 1 : 0;
 464}
 465
 466/*   Flush the tx ring. This function is only safe to
 467 *   call from the qcaspi_spi_thread.
 468 */
 469
 470static void
 471qcaspi_flush_tx_ring(struct qcaspi *qca)
 472{
 473	int i;
 474
 475	/* XXX After inconsistent lock states netif_tx_lock()
 476	 * has been replaced by netif_tx_lock_bh() and so on.
 477	 */
 478	netif_tx_lock_bh(qca->net_dev);
 479	for (i = 0; i < TX_RING_MAX_LEN; i++) {
 480		if (qca->txr.skb[i]) {
 481			dev_kfree_skb(qca->txr.skb[i]);
 482			qca->txr.skb[i] = NULL;
 483			qca->net_dev->stats.tx_dropped++;
 484		}
 485	}
 486	qca->txr.tail = 0;
 487	qca->txr.head = 0;
 488	qca->txr.size = 0;
 489	netif_tx_unlock_bh(qca->net_dev);
 490}
 491
 492static void
 493qcaspi_qca7k_sync(struct qcaspi *qca, int event)
 494{
 495	u16 signature = 0;
 496	u16 spi_config;
 497	u16 wrbuf_space = 0;
 498
 499	if (event == QCASPI_EVENT_CPUON) {
 500		/* Read signature twice, if not valid
 501		 * go back to unknown state.
 502		 */
 503		qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
 504		qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
 505		if (signature != QCASPI_GOOD_SIGNATURE) {
 506			if (qca->sync == QCASPI_SYNC_READY)
 507				qca->stats.bad_signature++;
 508
 509			qca->sync = QCASPI_SYNC_UNKNOWN;
 510			netdev_dbg(qca->net_dev, "sync: got CPU on, but signature was invalid, restart\n");
 511			return;
 512		} else {
 513			/* ensure that the WRBUF is empty */
 514			qcaspi_read_register(qca, SPI_REG_WRBUF_SPC_AVA,
 515					     &wrbuf_space);
 516			if (wrbuf_space != QCASPI_HW_BUF_LEN) {
 517				netdev_dbg(qca->net_dev, "sync: got CPU on, but wrbuf not empty. reset!\n");
 518				qca->sync = QCASPI_SYNC_UNKNOWN;
 519			} else {
 520				netdev_dbg(qca->net_dev, "sync: got CPU on, now in sync\n");
 521				qca->sync = QCASPI_SYNC_READY;
 522				return;
 523			}
 524		}
 525	}
 526
 527	switch (qca->sync) {
 528	case QCASPI_SYNC_READY:
 529		/* Check signature twice, if not valid go to unknown state. */
 530		qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
 531		if (signature != QCASPI_GOOD_SIGNATURE)
 532			qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
 533
 534		if (signature != QCASPI_GOOD_SIGNATURE) {
 535			qca->sync = QCASPI_SYNC_UNKNOWN;
 536			qca->stats.bad_signature++;
 537			netdev_dbg(qca->net_dev, "sync: bad signature, restart\n");
 538			/* don't reset right away */
 539			return;
 540		}
 541		break;
 542	case QCASPI_SYNC_UNKNOWN:
 543		/* Read signature, if not valid stay in unknown state */
 544		qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
 545		if (signature != QCASPI_GOOD_SIGNATURE) {
 546			netdev_dbg(qca->net_dev, "sync: could not read signature to reset device, retry.\n");
 547			return;
 548		}
 549
 550		/* TODO: use GPIO to reset QCA7000 in legacy mode*/
 551		netdev_dbg(qca->net_dev, "sync: resetting device.\n");
 552		qcaspi_read_register(qca, SPI_REG_SPI_CONFIG, &spi_config);
 553		spi_config |= QCASPI_SLAVE_RESET_BIT;
 554		qcaspi_write_register(qca, SPI_REG_SPI_CONFIG, spi_config, 0);
 555
 556		qca->sync = QCASPI_SYNC_RESET;
 557		qca->stats.trig_reset++;
 558		qca->reset_count = 0;
 559		break;
 560	case QCASPI_SYNC_RESET:
 561		qca->reset_count++;
 562		netdev_dbg(qca->net_dev, "sync: waiting for CPU on, count %u.\n",
 563			   qca->reset_count);
 564		if (qca->reset_count >= QCASPI_RESET_TIMEOUT) {
 565			/* reset did not seem to take place, try again */
 566			qca->sync = QCASPI_SYNC_UNKNOWN;
 567			qca->stats.reset_timeout++;
 568			netdev_dbg(qca->net_dev, "sync: reset timeout, restarting process.\n");
 569		}
 570		break;
 571	}
 572}
 573
 574static int
 575qcaspi_spi_thread(void *data)
 576{
 577	struct qcaspi *qca = data;
 578	u16 intr_cause = 0;
 579
 580	netdev_info(qca->net_dev, "SPI thread created\n");
 581	while (!kthread_should_stop()) {
 582		set_current_state(TASK_INTERRUPTIBLE);
 583		if (kthread_should_park()) {
 584			netif_tx_disable(qca->net_dev);
 585			netif_carrier_off(qca->net_dev);
 586			qcaspi_flush_tx_ring(qca);
 587			kthread_parkme();
 588			if (qca->sync == QCASPI_SYNC_READY) {
 589				netif_carrier_on(qca->net_dev);
 590				netif_wake_queue(qca->net_dev);
 591			}
 592			continue;
 593		}
 594
 595		if ((qca->intr_req == qca->intr_svc) &&
 596		    !qca->txr.skb[qca->txr.head])
 
 597			schedule();
 598
 599		set_current_state(TASK_RUNNING);
 600
 601		netdev_dbg(qca->net_dev, "have work to do. int: %d, tx_skb: %p\n",
 602			   qca->intr_req - qca->intr_svc,
 603			   qca->txr.skb[qca->txr.head]);
 604
 605		qcaspi_qca7k_sync(qca, QCASPI_EVENT_UPDATE);
 606
 607		if (qca->sync != QCASPI_SYNC_READY) {
 608			netdev_dbg(qca->net_dev, "sync: not ready %u, turn off carrier and flush\n",
 609				   (unsigned int)qca->sync);
 610			netif_stop_queue(qca->net_dev);
 611			netif_carrier_off(qca->net_dev);
 612			qcaspi_flush_tx_ring(qca);
 613			msleep(QCASPI_QCA7K_REBOOT_TIME_MS);
 614		}
 615
 616		if (qca->intr_svc != qca->intr_req) {
 617			qca->intr_svc = qca->intr_req;
 618			start_spi_intr_handling(qca, &intr_cause);
 619
 620			if (intr_cause & SPI_INT_CPU_ON) {
 621				qcaspi_qca7k_sync(qca, QCASPI_EVENT_CPUON);
 622
 623				/* Frame decoding in progress */
 624				if (qca->frm_handle.state != qca->frm_handle.init)
 625					qca->net_dev->stats.rx_dropped++;
 626
 627				qcafrm_fsm_init_spi(&qca->frm_handle);
 628				qca->stats.device_reset++;
 629
 630				/* not synced. */
 631				if (qca->sync != QCASPI_SYNC_READY)
 632					continue;
 633
 
 634				netif_wake_queue(qca->net_dev);
 635				netif_carrier_on(qca->net_dev);
 636			}
 637
 638			if (intr_cause & SPI_INT_RDBUF_ERR) {
 639				/* restart sync */
 640				netdev_dbg(qca->net_dev, "===> rdbuf error!\n");
 641				qca->stats.read_buf_err++;
 642				qca->sync = QCASPI_SYNC_UNKNOWN;
 643				continue;
 644			}
 645
 646			if (intr_cause & SPI_INT_WRBUF_ERR) {
 647				/* restart sync */
 648				netdev_dbg(qca->net_dev, "===> wrbuf error!\n");
 649				qca->stats.write_buf_err++;
 650				qca->sync = QCASPI_SYNC_UNKNOWN;
 651				continue;
 652			}
 653
 654			/* can only handle other interrupts
 655			 * if sync has occurred
 656			 */
 657			if (qca->sync == QCASPI_SYNC_READY) {
 658				if (intr_cause & SPI_INT_PKT_AVLBL)
 659					qcaspi_receive(qca);
 660			}
 661
 662			end_spi_intr_handling(qca, intr_cause);
 663		}
 664
 665		if (qca->sync == QCASPI_SYNC_READY)
 666			qcaspi_transmit(qca);
 667	}
 668	set_current_state(TASK_RUNNING);
 669	netdev_info(qca->net_dev, "SPI thread exit\n");
 670
 671	return 0;
 672}
 673
 674static irqreturn_t
 675qcaspi_intr_handler(int irq, void *data)
 676{
 677	struct qcaspi *qca = data;
 678
 679	qca->intr_req++;
 680	if (qca->spi_thread)
 681		wake_up_process(qca->spi_thread);
 682
 683	return IRQ_HANDLED;
 684}
 685
 686static int
 687qcaspi_netdev_open(struct net_device *dev)
 688{
 689	struct qcaspi *qca = netdev_priv(dev);
 690	int ret = 0;
 691
 692	if (!qca)
 693		return -EINVAL;
 694
 695	qca->intr_req = 1;
 696	qca->intr_svc = 0;
 697	qca->sync = QCASPI_SYNC_UNKNOWN;
 698	qcafrm_fsm_init_spi(&qca->frm_handle);
 699
 700	qca->spi_thread = kthread_run((void *)qcaspi_spi_thread,
 701				      qca, "%s", dev->name);
 702
 703	if (IS_ERR(qca->spi_thread)) {
 704		netdev_err(dev, "%s: unable to start kernel thread.\n",
 705			   QCASPI_DRV_NAME);
 706		return PTR_ERR(qca->spi_thread);
 707	}
 708
 709	ret = request_irq(qca->spi_dev->irq, qcaspi_intr_handler, 0,
 710			  dev->name, qca);
 711	if (ret) {
 712		netdev_err(dev, "%s: unable to get IRQ %d (irqval=%d).\n",
 713			   QCASPI_DRV_NAME, qca->spi_dev->irq, ret);
 714		kthread_stop(qca->spi_thread);
 715		return ret;
 716	}
 717
 718	/* SPI thread takes care of TX queue */
 719
 720	return 0;
 721}
 722
 723static int
 724qcaspi_netdev_close(struct net_device *dev)
 725{
 726	struct qcaspi *qca = netdev_priv(dev);
 727
 728	netif_stop_queue(dev);
 729
 730	qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, 0, wr_verify);
 731	free_irq(qca->spi_dev->irq, qca);
 732
 733	kthread_stop(qca->spi_thread);
 734	qca->spi_thread = NULL;
 735	qcaspi_flush_tx_ring(qca);
 736
 737	return 0;
 738}
 739
 740static netdev_tx_t
 741qcaspi_netdev_xmit(struct sk_buff *skb, struct net_device *dev)
 742{
 743	u32 frame_len;
 744	u8 *ptmp;
 745	struct qcaspi *qca = netdev_priv(dev);
 746	u16 new_tail;
 747	struct sk_buff *tskb;
 748	u8 pad_len = 0;
 749
 750	if (skb->len < QCAFRM_MIN_LEN)
 751		pad_len = QCAFRM_MIN_LEN - skb->len;
 752
 753	if (qca->txr.skb[qca->txr.tail]) {
 754		netdev_warn(qca->net_dev, "queue was unexpectedly full!\n");
 755		netif_stop_queue(qca->net_dev);
 756		qca->stats.ring_full++;
 757		return NETDEV_TX_BUSY;
 758	}
 759
 760	if ((skb_headroom(skb) < QCAFRM_HEADER_LEN) ||
 761	    (skb_tailroom(skb) < QCAFRM_FOOTER_LEN + pad_len)) {
 762		tskb = skb_copy_expand(skb, QCAFRM_HEADER_LEN,
 763				       QCAFRM_FOOTER_LEN + pad_len, GFP_ATOMIC);
 764		if (!tskb) {
 765			qca->stats.out_of_mem++;
 766			return NETDEV_TX_BUSY;
 767		}
 768		dev_kfree_skb(skb);
 769		skb = tskb;
 770	}
 771
 772	frame_len = skb->len + pad_len;
 773
 774	ptmp = skb_push(skb, QCAFRM_HEADER_LEN);
 775	qcafrm_create_header(ptmp, frame_len);
 776
 777	if (pad_len) {
 778		ptmp = skb_put_zero(skb, pad_len);
 779	}
 780
 781	ptmp = skb_put(skb, QCAFRM_FOOTER_LEN);
 782	qcafrm_create_footer(ptmp);
 783
 784	netdev_dbg(qca->net_dev, "Tx-ing packet: Size: 0x%08x\n",
 785		   skb->len);
 786
 787	qca->txr.size += skb->len + QCASPI_HW_PKT_LEN;
 788
 789	new_tail = qca->txr.tail + 1;
 790	if (new_tail >= qca->txr.count)
 791		new_tail = 0;
 792
 793	qca->txr.skb[qca->txr.tail] = skb;
 794	qca->txr.tail = new_tail;
 795
 796	if (!qcaspi_tx_ring_has_space(&qca->txr)) {
 797		netif_stop_queue(qca->net_dev);
 798		qca->stats.ring_full++;
 799	}
 800
 801	netif_trans_update(dev);
 802
 803	if (qca->spi_thread)
 804		wake_up_process(qca->spi_thread);
 805
 806	return NETDEV_TX_OK;
 807}
 808
 809static void
 810qcaspi_netdev_tx_timeout(struct net_device *dev, unsigned int txqueue)
 811{
 812	struct qcaspi *qca = netdev_priv(dev);
 813
 814	netdev_info(qca->net_dev, "Transmit timeout at %ld, latency %ld\n",
 815		    jiffies, jiffies - dev_trans_start(dev));
 816	qca->net_dev->stats.tx_errors++;
 817	/* Trigger tx queue flush and QCA7000 reset */
 818	qca->sync = QCASPI_SYNC_UNKNOWN;
 819
 820	if (qca->spi_thread)
 821		wake_up_process(qca->spi_thread);
 822}
 823
 824static int
 825qcaspi_netdev_init(struct net_device *dev)
 826{
 827	struct qcaspi *qca = netdev_priv(dev);
 828
 829	dev->mtu = QCAFRM_MAX_MTU;
 830	dev->type = ARPHRD_ETHER;
 831	qca->clkspeed = qcaspi_clkspeed;
 832	qca->burst_len = qcaspi_burst_len;
 833	qca->spi_thread = NULL;
 834	qca->buffer_size = (dev->mtu + VLAN_ETH_HLEN + QCAFRM_HEADER_LEN +
 835		QCAFRM_FOOTER_LEN + 4) * 4;
 836
 837	memset(&qca->stats, 0, sizeof(struct qcaspi_stats));
 838
 839	qca->rx_buffer = kmalloc(qca->buffer_size, GFP_KERNEL);
 840	if (!qca->rx_buffer)
 841		return -ENOBUFS;
 842
 843	qca->rx_skb = netdev_alloc_skb_ip_align(dev, qca->net_dev->mtu +
 844						VLAN_ETH_HLEN);
 845	if (!qca->rx_skb) {
 846		kfree(qca->rx_buffer);
 847		netdev_info(qca->net_dev, "Failed to allocate RX sk_buff.\n");
 848		return -ENOBUFS;
 849	}
 850
 851	return 0;
 852}
 853
 854static void
 855qcaspi_netdev_uninit(struct net_device *dev)
 856{
 857	struct qcaspi *qca = netdev_priv(dev);
 858
 859	kfree(qca->rx_buffer);
 860	qca->buffer_size = 0;
 861	dev_kfree_skb(qca->rx_skb);
 862}
 863
 864static const struct net_device_ops qcaspi_netdev_ops = {
 865	.ndo_init = qcaspi_netdev_init,
 866	.ndo_uninit = qcaspi_netdev_uninit,
 867	.ndo_open = qcaspi_netdev_open,
 868	.ndo_stop = qcaspi_netdev_close,
 869	.ndo_start_xmit = qcaspi_netdev_xmit,
 870	.ndo_set_mac_address = eth_mac_addr,
 871	.ndo_tx_timeout = qcaspi_netdev_tx_timeout,
 872	.ndo_validate_addr = eth_validate_addr,
 873};
 874
 875static void
 876qcaspi_netdev_setup(struct net_device *dev)
 877{
 878	struct qcaspi *qca = NULL;
 879
 880	dev->netdev_ops = &qcaspi_netdev_ops;
 881	qcaspi_set_ethtool_ops(dev);
 882	dev->watchdog_timeo = QCASPI_TX_TIMEOUT;
 883	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
 884	dev->tx_queue_len = 100;
 885
 886	/* MTU range: 46 - 1500 */
 887	dev->min_mtu = QCAFRM_MIN_MTU;
 888	dev->max_mtu = QCAFRM_MAX_MTU;
 889
 890	qca = netdev_priv(dev);
 891	memset(qca, 0, sizeof(struct qcaspi));
 892
 893	memset(&qca->txr, 0, sizeof(qca->txr));
 894	qca->txr.count = TX_RING_MAX_LEN;
 895}
 896
 897static const struct of_device_id qca_spi_of_match[] = {
 898	{ .compatible = "qca,qca7000" },
 899	{ /* sentinel */ }
 900};
 901MODULE_DEVICE_TABLE(of, qca_spi_of_match);
 902
 903static int
 904qca_spi_probe(struct spi_device *spi)
 905{
 906	struct qcaspi *qca = NULL;
 907	struct net_device *qcaspi_devs = NULL;
 908	u8 legacy_mode = 0;
 909	u16 signature;
 910	int ret;
 911
 912	if (!spi->dev.of_node) {
 913		dev_err(&spi->dev, "Missing device tree\n");
 914		return -EINVAL;
 915	}
 916
 917	legacy_mode = of_property_read_bool(spi->dev.of_node,
 918					    "qca,legacy-mode");
 919
 920	if (qcaspi_clkspeed == 0) {
 921		if (spi->max_speed_hz)
 922			qcaspi_clkspeed = spi->max_speed_hz;
 923		else
 924			qcaspi_clkspeed = QCASPI_CLK_SPEED;
 925	}
 926
 927	if ((qcaspi_clkspeed < QCASPI_CLK_SPEED_MIN) ||
 928	    (qcaspi_clkspeed > QCASPI_CLK_SPEED_MAX)) {
 929		dev_err(&spi->dev, "Invalid clkspeed: %d\n",
 930			qcaspi_clkspeed);
 931		return -EINVAL;
 932	}
 933
 934	if ((qcaspi_burst_len < QCASPI_BURST_LEN_MIN) ||
 935	    (qcaspi_burst_len > QCASPI_BURST_LEN_MAX)) {
 936		dev_err(&spi->dev, "Invalid burst len: %d\n",
 937			qcaspi_burst_len);
 938		return -EINVAL;
 939	}
 940
 941	if ((qcaspi_pluggable < QCASPI_PLUGGABLE_MIN) ||
 942	    (qcaspi_pluggable > QCASPI_PLUGGABLE_MAX)) {
 943		dev_err(&spi->dev, "Invalid pluggable: %d\n",
 944			qcaspi_pluggable);
 945		return -EINVAL;
 946	}
 947
 948	if (wr_verify < QCASPI_WRITE_VERIFY_MIN ||
 949	    wr_verify > QCASPI_WRITE_VERIFY_MAX) {
 950		dev_err(&spi->dev, "Invalid write verify: %d\n",
 951			wr_verify);
 952		return -EINVAL;
 953	}
 954
 955	dev_info(&spi->dev, "ver=%s, clkspeed=%d, burst_len=%d, pluggable=%d\n",
 956		 QCASPI_DRV_VERSION,
 957		 qcaspi_clkspeed,
 958		 qcaspi_burst_len,
 959		 qcaspi_pluggable);
 960
 961	spi->mode = SPI_MODE_3;
 962	spi->max_speed_hz = qcaspi_clkspeed;
 963	if (spi_setup(spi) < 0) {
 964		dev_err(&spi->dev, "Unable to setup SPI device\n");
 965		return -EFAULT;
 966	}
 967
 968	qcaspi_devs = alloc_etherdev(sizeof(struct qcaspi));
 969	if (!qcaspi_devs)
 970		return -ENOMEM;
 971
 972	qcaspi_netdev_setup(qcaspi_devs);
 973	SET_NETDEV_DEV(qcaspi_devs, &spi->dev);
 974
 975	qca = netdev_priv(qcaspi_devs);
 976	if (!qca) {
 977		free_netdev(qcaspi_devs);
 978		dev_err(&spi->dev, "Fail to retrieve private structure\n");
 979		return -ENOMEM;
 980	}
 981	qca->net_dev = qcaspi_devs;
 982	qca->spi_dev = spi;
 983	qca->legacy_mode = legacy_mode;
 984
 985	spi_set_drvdata(spi, qcaspi_devs);
 986
 987	ret = of_get_ethdev_address(spi->dev.of_node, qca->net_dev);
 988	if (ret) {
 989		eth_hw_addr_random(qca->net_dev);
 990		dev_info(&spi->dev, "Using random MAC address: %pM\n",
 991			 qca->net_dev->dev_addr);
 992	}
 993
 994	netif_carrier_off(qca->net_dev);
 995
 996	if (!qcaspi_pluggable) {
 997		qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
 998		qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
 999
1000		if (signature != QCASPI_GOOD_SIGNATURE) {
1001			dev_err(&spi->dev, "Invalid signature (0x%04X)\n",
1002				signature);
1003			free_netdev(qcaspi_devs);
1004			return -EFAULT;
1005		}
1006	}
1007
1008	if (register_netdev(qcaspi_devs)) {
1009		dev_err(&spi->dev, "Unable to register net device %s\n",
1010			qcaspi_devs->name);
1011		free_netdev(qcaspi_devs);
1012		return -EFAULT;
1013	}
1014
1015	qcaspi_init_device_debugfs(qca);
1016
1017	return 0;
1018}
1019
1020static void
1021qca_spi_remove(struct spi_device *spi)
1022{
1023	struct net_device *qcaspi_devs = spi_get_drvdata(spi);
1024	struct qcaspi *qca = netdev_priv(qcaspi_devs);
1025
1026	qcaspi_remove_device_debugfs(qca);
1027
1028	unregister_netdev(qcaspi_devs);
1029	free_netdev(qcaspi_devs);
1030}
1031
1032static const struct spi_device_id qca_spi_id[] = {
1033	{ "qca7000", 0 },
1034	{ /* sentinel */ }
1035};
1036MODULE_DEVICE_TABLE(spi, qca_spi_id);
1037
1038static struct spi_driver qca_spi_driver = {
1039	.driver	= {
1040		.name	= QCASPI_DRV_NAME,
1041		.of_match_table = qca_spi_of_match,
1042	},
1043	.id_table = qca_spi_id,
1044	.probe    = qca_spi_probe,
1045	.remove   = qca_spi_remove,
1046};
1047module_spi_driver(qca_spi_driver);
1048
1049MODULE_DESCRIPTION("Qualcomm Atheros QCA7000 SPI Driver");
1050MODULE_AUTHOR("Qualcomm Atheros Communications");
1051MODULE_AUTHOR("Stefan Wahren <stefan.wahren@i2se.com>");
1052MODULE_LICENSE("Dual BSD/GPL");
1053MODULE_VERSION(QCASPI_DRV_VERSION);
v6.2
   1/*
   2 *   Copyright (c) 2011, 2012, Qualcomm Atheros Communications Inc.
   3 *   Copyright (c) 2014, I2SE GmbH
   4 *
   5 *   Permission to use, copy, modify, and/or distribute this software
   6 *   for any purpose with or without fee is hereby granted, provided
   7 *   that the above copyright notice and this permission notice appear
   8 *   in all copies.
   9 *
  10 *   THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
  11 *   WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
  12 *   WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
  13 *   THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
  14 *   CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  15 *   LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
  16 *   NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
  17 *   CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18 */
  19
  20/*   This module implements the Qualcomm Atheros SPI protocol for
  21 *   kernel-based SPI device; it is essentially an Ethernet-to-SPI
  22 *   serial converter;
  23 */
  24
  25#include <linux/errno.h>
  26#include <linux/etherdevice.h>
  27#include <linux/if_arp.h>
  28#include <linux/if_ether.h>
  29#include <linux/init.h>
  30#include <linux/interrupt.h>
  31#include <linux/jiffies.h>
  32#include <linux/kernel.h>
  33#include <linux/kthread.h>
  34#include <linux/module.h>
  35#include <linux/moduleparam.h>
  36#include <linux/netdevice.h>
  37#include <linux/of.h>
  38#include <linux/of_device.h>
  39#include <linux/of_net.h>
  40#include <linux/sched.h>
  41#include <linux/skbuff.h>
  42#include <linux/spi/spi.h>
  43#include <linux/types.h>
  44
  45#include "qca_7k.h"
  46#include "qca_7k_common.h"
  47#include "qca_debug.h"
  48#include "qca_spi.h"
  49
  50#define MAX_DMA_BURST_LEN 5000
  51
  52/*   Modules parameters     */
  53#define QCASPI_CLK_SPEED_MIN 1000000
  54#define QCASPI_CLK_SPEED_MAX 16000000
  55#define QCASPI_CLK_SPEED     8000000
  56static int qcaspi_clkspeed;
  57module_param(qcaspi_clkspeed, int, 0);
  58MODULE_PARM_DESC(qcaspi_clkspeed, "SPI bus clock speed (Hz). Use 1000000-16000000.");
  59
  60#define QCASPI_BURST_LEN_MIN 1
  61#define QCASPI_BURST_LEN_MAX MAX_DMA_BURST_LEN
  62static int qcaspi_burst_len = MAX_DMA_BURST_LEN;
  63module_param(qcaspi_burst_len, int, 0);
  64MODULE_PARM_DESC(qcaspi_burst_len, "Number of data bytes per burst. Use 1-5000.");
  65
  66#define QCASPI_PLUGGABLE_MIN 0
  67#define QCASPI_PLUGGABLE_MAX 1
  68static int qcaspi_pluggable = QCASPI_PLUGGABLE_MIN;
  69module_param(qcaspi_pluggable, int, 0);
  70MODULE_PARM_DESC(qcaspi_pluggable, "Pluggable SPI connection (yes/no).");
  71
  72#define QCASPI_WRITE_VERIFY_MIN 0
  73#define QCASPI_WRITE_VERIFY_MAX 3
  74static int wr_verify = QCASPI_WRITE_VERIFY_MIN;
  75module_param(wr_verify, int, 0);
  76MODULE_PARM_DESC(wr_verify, "SPI register write verify trails. Use 0-3.");
  77
  78#define QCASPI_TX_TIMEOUT (1 * HZ)
  79#define QCASPI_QCA7K_REBOOT_TIME_MS 1000
  80
  81static void
  82start_spi_intr_handling(struct qcaspi *qca, u16 *intr_cause)
  83{
  84	*intr_cause = 0;
  85
  86	qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, 0, wr_verify);
  87	qcaspi_read_register(qca, SPI_REG_INTR_CAUSE, intr_cause);
  88	netdev_dbg(qca->net_dev, "interrupts: 0x%04x\n", *intr_cause);
  89}
  90
  91static void
  92end_spi_intr_handling(struct qcaspi *qca, u16 intr_cause)
  93{
  94	u16 intr_enable = (SPI_INT_CPU_ON |
  95			   SPI_INT_PKT_AVLBL |
  96			   SPI_INT_RDBUF_ERR |
  97			   SPI_INT_WRBUF_ERR);
  98
  99	qcaspi_write_register(qca, SPI_REG_INTR_CAUSE, intr_cause, 0);
 100	qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, intr_enable, wr_verify);
 101	netdev_dbg(qca->net_dev, "acking int: 0x%04x\n", intr_cause);
 102}
 103
 104static u32
 105qcaspi_write_burst(struct qcaspi *qca, u8 *src, u32 len)
 106{
 107	__be16 cmd;
 108	struct spi_message msg;
 109	struct spi_transfer transfer[2];
 110	int ret;
 111
 112	memset(&transfer, 0, sizeof(transfer));
 113	spi_message_init(&msg);
 114
 115	cmd = cpu_to_be16(QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL);
 116	transfer[0].tx_buf = &cmd;
 117	transfer[0].len = QCASPI_CMD_LEN;
 118	transfer[1].tx_buf = src;
 119	transfer[1].len = len;
 120
 121	spi_message_add_tail(&transfer[0], &msg);
 122	spi_message_add_tail(&transfer[1], &msg);
 123	ret = spi_sync(qca->spi_dev, &msg);
 124
 125	if (ret || (msg.actual_length != QCASPI_CMD_LEN + len)) {
 126		qcaspi_spi_error(qca);
 127		return 0;
 128	}
 129
 130	return len;
 131}
 132
 133static u32
 134qcaspi_write_legacy(struct qcaspi *qca, u8 *src, u32 len)
 135{
 136	struct spi_message msg;
 137	struct spi_transfer transfer;
 138	int ret;
 139
 140	memset(&transfer, 0, sizeof(transfer));
 141	spi_message_init(&msg);
 142
 143	transfer.tx_buf = src;
 144	transfer.len = len;
 145
 146	spi_message_add_tail(&transfer, &msg);
 147	ret = spi_sync(qca->spi_dev, &msg);
 148
 149	if (ret || (msg.actual_length != len)) {
 150		qcaspi_spi_error(qca);
 151		return 0;
 152	}
 153
 154	return len;
 155}
 156
 157static u32
 158qcaspi_read_burst(struct qcaspi *qca, u8 *dst, u32 len)
 159{
 160	struct spi_message msg;
 161	__be16 cmd;
 162	struct spi_transfer transfer[2];
 163	int ret;
 164
 165	memset(&transfer, 0, sizeof(transfer));
 166	spi_message_init(&msg);
 167
 168	cmd = cpu_to_be16(QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL);
 169	transfer[0].tx_buf = &cmd;
 170	transfer[0].len = QCASPI_CMD_LEN;
 171	transfer[1].rx_buf = dst;
 172	transfer[1].len = len;
 173
 174	spi_message_add_tail(&transfer[0], &msg);
 175	spi_message_add_tail(&transfer[1], &msg);
 176	ret = spi_sync(qca->spi_dev, &msg);
 177
 178	if (ret || (msg.actual_length != QCASPI_CMD_LEN + len)) {
 179		qcaspi_spi_error(qca);
 180		return 0;
 181	}
 182
 183	return len;
 184}
 185
 186static u32
 187qcaspi_read_legacy(struct qcaspi *qca, u8 *dst, u32 len)
 188{
 189	struct spi_message msg;
 190	struct spi_transfer transfer;
 191	int ret;
 192
 193	memset(&transfer, 0, sizeof(transfer));
 194	spi_message_init(&msg);
 195
 196	transfer.rx_buf = dst;
 197	transfer.len = len;
 198
 199	spi_message_add_tail(&transfer, &msg);
 200	ret = spi_sync(qca->spi_dev, &msg);
 201
 202	if (ret || (msg.actual_length != len)) {
 203		qcaspi_spi_error(qca);
 204		return 0;
 205	}
 206
 207	return len;
 208}
 209
 210static int
 211qcaspi_tx_cmd(struct qcaspi *qca, u16 cmd)
 212{
 213	__be16 tx_data;
 214	struct spi_message msg;
 215	struct spi_transfer transfer;
 216	int ret;
 217
 218	memset(&transfer, 0, sizeof(transfer));
 219
 220	spi_message_init(&msg);
 221
 222	tx_data = cpu_to_be16(cmd);
 223	transfer.len = sizeof(cmd);
 224	transfer.tx_buf = &tx_data;
 225	spi_message_add_tail(&transfer, &msg);
 226
 227	ret = spi_sync(qca->spi_dev, &msg);
 228
 229	if (!ret)
 230		ret = msg.status;
 231
 232	if (ret)
 233		qcaspi_spi_error(qca);
 234
 235	return ret;
 236}
 237
 238static int
 239qcaspi_tx_frame(struct qcaspi *qca, struct sk_buff *skb)
 240{
 241	u32 count;
 242	u32 written;
 243	u32 offset;
 244	u32 len;
 245
 246	len = skb->len;
 247
 248	qcaspi_write_register(qca, SPI_REG_BFR_SIZE, len, wr_verify);
 249	if (qca->legacy_mode)
 250		qcaspi_tx_cmd(qca, QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL);
 251
 252	offset = 0;
 253	while (len) {
 254		count = len;
 255		if (count > qca->burst_len)
 256			count = qca->burst_len;
 257
 258		if (qca->legacy_mode) {
 259			written = qcaspi_write_legacy(qca,
 260						      skb->data + offset,
 261						      count);
 262		} else {
 263			written = qcaspi_write_burst(qca,
 264						     skb->data + offset,
 265						     count);
 266		}
 267
 268		if (written != count)
 269			return -1;
 270
 271		offset += count;
 272		len -= count;
 273	}
 274
 275	return 0;
 276}
 277
 278static int
 279qcaspi_transmit(struct qcaspi *qca)
 280{
 281	struct net_device_stats *n_stats = &qca->net_dev->stats;
 282	u16 available = 0;
 283	u32 pkt_len;
 284	u16 new_head;
 285	u16 packets = 0;
 286
 287	if (qca->txr.skb[qca->txr.head] == NULL)
 288		return 0;
 289
 290	qcaspi_read_register(qca, SPI_REG_WRBUF_SPC_AVA, &available);
 291
 292	if (available > QCASPI_HW_BUF_LEN) {
 293		/* This could only happen by interferences on the SPI line.
 294		 * So retry later ...
 295		 */
 296		qca->stats.buf_avail_err++;
 297		return -1;
 298	}
 299
 300	while (qca->txr.skb[qca->txr.head]) {
 301		pkt_len = qca->txr.skb[qca->txr.head]->len + QCASPI_HW_PKT_LEN;
 302
 303		if (available < pkt_len) {
 304			if (packets == 0)
 305				qca->stats.write_buf_miss++;
 306			break;
 307		}
 308
 309		if (qcaspi_tx_frame(qca, qca->txr.skb[qca->txr.head]) == -1) {
 310			qca->stats.write_err++;
 311			return -1;
 312		}
 313
 314		packets++;
 315		n_stats->tx_packets++;
 316		n_stats->tx_bytes += qca->txr.skb[qca->txr.head]->len;
 317		available -= pkt_len;
 318
 319		/* remove the skb from the queue */
 320		/* XXX After inconsistent lock states netif_tx_lock()
 321		 * has been replaced by netif_tx_lock_bh() and so on.
 322		 */
 323		netif_tx_lock_bh(qca->net_dev);
 324		dev_kfree_skb(qca->txr.skb[qca->txr.head]);
 325		qca->txr.skb[qca->txr.head] = NULL;
 326		qca->txr.size -= pkt_len;
 327		new_head = qca->txr.head + 1;
 328		if (new_head >= qca->txr.count)
 329			new_head = 0;
 330		qca->txr.head = new_head;
 331		if (netif_queue_stopped(qca->net_dev))
 332			netif_wake_queue(qca->net_dev);
 333		netif_tx_unlock_bh(qca->net_dev);
 334	}
 335
 336	return 0;
 337}
 338
 339static int
 340qcaspi_receive(struct qcaspi *qca)
 341{
 342	struct net_device *net_dev = qca->net_dev;
 343	struct net_device_stats *n_stats = &net_dev->stats;
 344	u16 available = 0;
 345	u32 bytes_read;
 346	u8 *cp;
 347
 348	/* Allocate rx SKB if we don't have one available. */
 349	if (!qca->rx_skb) {
 350		qca->rx_skb = netdev_alloc_skb_ip_align(net_dev,
 351							net_dev->mtu +
 352							VLAN_ETH_HLEN);
 353		if (!qca->rx_skb) {
 354			netdev_dbg(net_dev, "out of RX resources\n");
 355			qca->stats.out_of_mem++;
 356			return -1;
 357		}
 358	}
 359
 360	/* Read the packet size. */
 361	qcaspi_read_register(qca, SPI_REG_RDBUF_BYTE_AVA, &available);
 362
 363	netdev_dbg(net_dev, "qcaspi_receive: SPI_REG_RDBUF_BYTE_AVA: Value: %08x\n",
 364		   available);
 365
 366	if (available > QCASPI_HW_BUF_LEN + QCASPI_HW_PKT_LEN) {
 367		/* This could only happen by interferences on the SPI line.
 368		 * So retry later ...
 369		 */
 370		qca->stats.buf_avail_err++;
 371		return -1;
 372	} else if (available == 0) {
 373		netdev_dbg(net_dev, "qcaspi_receive called without any data being available!\n");
 374		return -1;
 375	}
 376
 377	qcaspi_write_register(qca, SPI_REG_BFR_SIZE, available, wr_verify);
 378
 379	if (qca->legacy_mode)
 380		qcaspi_tx_cmd(qca, QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL);
 381
 382	while (available) {
 383		u32 count = available;
 384
 385		if (count > qca->burst_len)
 386			count = qca->burst_len;
 387
 388		if (qca->legacy_mode) {
 389			bytes_read = qcaspi_read_legacy(qca, qca->rx_buffer,
 390							count);
 391		} else {
 392			bytes_read = qcaspi_read_burst(qca, qca->rx_buffer,
 393						       count);
 394		}
 395
 396		netdev_dbg(net_dev, "available: %d, byte read: %d\n",
 397			   available, bytes_read);
 398
 399		if (bytes_read) {
 400			available -= bytes_read;
 401		} else {
 402			qca->stats.read_err++;
 403			return -1;
 404		}
 405
 406		cp = qca->rx_buffer;
 407
 408		while ((bytes_read--) && (qca->rx_skb)) {
 409			s32 retcode;
 410
 411			retcode = qcafrm_fsm_decode(&qca->frm_handle,
 412						    qca->rx_skb->data,
 413						    skb_tailroom(qca->rx_skb),
 414						    *cp);
 415			cp++;
 416			switch (retcode) {
 417			case QCAFRM_GATHER:
 418			case QCAFRM_NOHEAD:
 419				break;
 420			case QCAFRM_NOTAIL:
 421				netdev_dbg(net_dev, "no RX tail\n");
 422				n_stats->rx_errors++;
 423				n_stats->rx_dropped++;
 424				break;
 425			case QCAFRM_INVLEN:
 426				netdev_dbg(net_dev, "invalid RX length\n");
 427				n_stats->rx_errors++;
 428				n_stats->rx_dropped++;
 429				break;
 430			default:
 431				qca->rx_skb->dev = qca->net_dev;
 432				n_stats->rx_packets++;
 433				n_stats->rx_bytes += retcode;
 434				skb_put(qca->rx_skb, retcode);
 435				qca->rx_skb->protocol = eth_type_trans(
 436					qca->rx_skb, qca->rx_skb->dev);
 437				skb_checksum_none_assert(qca->rx_skb);
 438				netif_rx(qca->rx_skb);
 439				qca->rx_skb = netdev_alloc_skb_ip_align(net_dev,
 440					net_dev->mtu + VLAN_ETH_HLEN);
 441				if (!qca->rx_skb) {
 442					netdev_dbg(net_dev, "out of RX resources\n");
 443					n_stats->rx_errors++;
 444					qca->stats.out_of_mem++;
 445					break;
 446				}
 447			}
 448		}
 449	}
 450
 451	return 0;
 452}
 453
 454/*   Check that tx ring stores only so much bytes
 455 *   that fit into the internal QCA buffer.
 456 */
 457
 458static int
 459qcaspi_tx_ring_has_space(struct tx_ring *txr)
 460{
 461	if (txr->skb[txr->tail])
 462		return 0;
 463
 464	return (txr->size + QCAFRM_MAX_LEN < QCASPI_HW_BUF_LEN) ? 1 : 0;
 465}
 466
 467/*   Flush the tx ring. This function is only safe to
 468 *   call from the qcaspi_spi_thread.
 469 */
 470
 471static void
 472qcaspi_flush_tx_ring(struct qcaspi *qca)
 473{
 474	int i;
 475
 476	/* XXX After inconsistent lock states netif_tx_lock()
 477	 * has been replaced by netif_tx_lock_bh() and so on.
 478	 */
 479	netif_tx_lock_bh(qca->net_dev);
 480	for (i = 0; i < TX_RING_MAX_LEN; i++) {
 481		if (qca->txr.skb[i]) {
 482			dev_kfree_skb(qca->txr.skb[i]);
 483			qca->txr.skb[i] = NULL;
 484			qca->net_dev->stats.tx_dropped++;
 485		}
 486	}
 487	qca->txr.tail = 0;
 488	qca->txr.head = 0;
 489	qca->txr.size = 0;
 490	netif_tx_unlock_bh(qca->net_dev);
 491}
 492
 493static void
 494qcaspi_qca7k_sync(struct qcaspi *qca, int event)
 495{
 496	u16 signature = 0;
 497	u16 spi_config;
 498	u16 wrbuf_space = 0;
 499
 500	if (event == QCASPI_EVENT_CPUON) {
 501		/* Read signature twice, if not valid
 502		 * go back to unknown state.
 503		 */
 504		qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
 505		qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
 506		if (signature != QCASPI_GOOD_SIGNATURE) {
 507			if (qca->sync == QCASPI_SYNC_READY)
 508				qca->stats.bad_signature++;
 509
 510			qca->sync = QCASPI_SYNC_UNKNOWN;
 511			netdev_dbg(qca->net_dev, "sync: got CPU on, but signature was invalid, restart\n");
 512			return;
 513		} else {
 514			/* ensure that the WRBUF is empty */
 515			qcaspi_read_register(qca, SPI_REG_WRBUF_SPC_AVA,
 516					     &wrbuf_space);
 517			if (wrbuf_space != QCASPI_HW_BUF_LEN) {
 518				netdev_dbg(qca->net_dev, "sync: got CPU on, but wrbuf not empty. reset!\n");
 519				qca->sync = QCASPI_SYNC_UNKNOWN;
 520			} else {
 521				netdev_dbg(qca->net_dev, "sync: got CPU on, now in sync\n");
 522				qca->sync = QCASPI_SYNC_READY;
 523				return;
 524			}
 525		}
 526	}
 527
 528	switch (qca->sync) {
 529	case QCASPI_SYNC_READY:
 530		/* Check signature twice, if not valid go to unknown state. */
 531		qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
 532		if (signature != QCASPI_GOOD_SIGNATURE)
 533			qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
 534
 535		if (signature != QCASPI_GOOD_SIGNATURE) {
 536			qca->sync = QCASPI_SYNC_UNKNOWN;
 537			qca->stats.bad_signature++;
 538			netdev_dbg(qca->net_dev, "sync: bad signature, restart\n");
 539			/* don't reset right away */
 540			return;
 541		}
 542		break;
 543	case QCASPI_SYNC_UNKNOWN:
 544		/* Read signature, if not valid stay in unknown state */
 545		qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
 546		if (signature != QCASPI_GOOD_SIGNATURE) {
 547			netdev_dbg(qca->net_dev, "sync: could not read signature to reset device, retry.\n");
 548			return;
 549		}
 550
 551		/* TODO: use GPIO to reset QCA7000 in legacy mode*/
 552		netdev_dbg(qca->net_dev, "sync: resetting device.\n");
 553		qcaspi_read_register(qca, SPI_REG_SPI_CONFIG, &spi_config);
 554		spi_config |= QCASPI_SLAVE_RESET_BIT;
 555		qcaspi_write_register(qca, SPI_REG_SPI_CONFIG, spi_config, 0);
 556
 557		qca->sync = QCASPI_SYNC_RESET;
 558		qca->stats.trig_reset++;
 559		qca->reset_count = 0;
 560		break;
 561	case QCASPI_SYNC_RESET:
 562		qca->reset_count++;
 563		netdev_dbg(qca->net_dev, "sync: waiting for CPU on, count %u.\n",
 564			   qca->reset_count);
 565		if (qca->reset_count >= QCASPI_RESET_TIMEOUT) {
 566			/* reset did not seem to take place, try again */
 567			qca->sync = QCASPI_SYNC_UNKNOWN;
 568			qca->stats.reset_timeout++;
 569			netdev_dbg(qca->net_dev, "sync: reset timeout, restarting process.\n");
 570		}
 571		break;
 572	}
 573}
 574
 575static int
 576qcaspi_spi_thread(void *data)
 577{
 578	struct qcaspi *qca = data;
 579	u16 intr_cause = 0;
 580
 581	netdev_info(qca->net_dev, "SPI thread created\n");
 582	while (!kthread_should_stop()) {
 583		set_current_state(TASK_INTERRUPTIBLE);
 
 
 
 
 
 
 
 
 
 
 
 
 584		if ((qca->intr_req == qca->intr_svc) &&
 585		    (qca->txr.skb[qca->txr.head] == NULL) &&
 586		    (qca->sync == QCASPI_SYNC_READY))
 587			schedule();
 588
 589		set_current_state(TASK_RUNNING);
 590
 591		netdev_dbg(qca->net_dev, "have work to do. int: %d, tx_skb: %p\n",
 592			   qca->intr_req - qca->intr_svc,
 593			   qca->txr.skb[qca->txr.head]);
 594
 595		qcaspi_qca7k_sync(qca, QCASPI_EVENT_UPDATE);
 596
 597		if (qca->sync != QCASPI_SYNC_READY) {
 598			netdev_dbg(qca->net_dev, "sync: not ready %u, turn off carrier and flush\n",
 599				   (unsigned int)qca->sync);
 600			netif_stop_queue(qca->net_dev);
 601			netif_carrier_off(qca->net_dev);
 602			qcaspi_flush_tx_ring(qca);
 603			msleep(QCASPI_QCA7K_REBOOT_TIME_MS);
 604		}
 605
 606		if (qca->intr_svc != qca->intr_req) {
 607			qca->intr_svc = qca->intr_req;
 608			start_spi_intr_handling(qca, &intr_cause);
 609
 610			if (intr_cause & SPI_INT_CPU_ON) {
 611				qcaspi_qca7k_sync(qca, QCASPI_EVENT_CPUON);
 612
 
 
 
 
 
 
 
 613				/* not synced. */
 614				if (qca->sync != QCASPI_SYNC_READY)
 615					continue;
 616
 617				qca->stats.device_reset++;
 618				netif_wake_queue(qca->net_dev);
 619				netif_carrier_on(qca->net_dev);
 620			}
 621
 622			if (intr_cause & SPI_INT_RDBUF_ERR) {
 623				/* restart sync */
 624				netdev_dbg(qca->net_dev, "===> rdbuf error!\n");
 625				qca->stats.read_buf_err++;
 626				qca->sync = QCASPI_SYNC_UNKNOWN;
 627				continue;
 628			}
 629
 630			if (intr_cause & SPI_INT_WRBUF_ERR) {
 631				/* restart sync */
 632				netdev_dbg(qca->net_dev, "===> wrbuf error!\n");
 633				qca->stats.write_buf_err++;
 634				qca->sync = QCASPI_SYNC_UNKNOWN;
 635				continue;
 636			}
 637
 638			/* can only handle other interrupts
 639			 * if sync has occurred
 640			 */
 641			if (qca->sync == QCASPI_SYNC_READY) {
 642				if (intr_cause & SPI_INT_PKT_AVLBL)
 643					qcaspi_receive(qca);
 644			}
 645
 646			end_spi_intr_handling(qca, intr_cause);
 647		}
 648
 649		if (qca->sync == QCASPI_SYNC_READY)
 650			qcaspi_transmit(qca);
 651	}
 652	set_current_state(TASK_RUNNING);
 653	netdev_info(qca->net_dev, "SPI thread exit\n");
 654
 655	return 0;
 656}
 657
 658static irqreturn_t
 659qcaspi_intr_handler(int irq, void *data)
 660{
 661	struct qcaspi *qca = data;
 662
 663	qca->intr_req++;
 664	if (qca->spi_thread)
 665		wake_up_process(qca->spi_thread);
 666
 667	return IRQ_HANDLED;
 668}
 669
 670static int
 671qcaspi_netdev_open(struct net_device *dev)
 672{
 673	struct qcaspi *qca = netdev_priv(dev);
 674	int ret = 0;
 675
 676	if (!qca)
 677		return -EINVAL;
 678
 679	qca->intr_req = 1;
 680	qca->intr_svc = 0;
 681	qca->sync = QCASPI_SYNC_UNKNOWN;
 682	qcafrm_fsm_init_spi(&qca->frm_handle);
 683
 684	qca->spi_thread = kthread_run((void *)qcaspi_spi_thread,
 685				      qca, "%s", dev->name);
 686
 687	if (IS_ERR(qca->spi_thread)) {
 688		netdev_err(dev, "%s: unable to start kernel thread.\n",
 689			   QCASPI_DRV_NAME);
 690		return PTR_ERR(qca->spi_thread);
 691	}
 692
 693	ret = request_irq(qca->spi_dev->irq, qcaspi_intr_handler, 0,
 694			  dev->name, qca);
 695	if (ret) {
 696		netdev_err(dev, "%s: unable to get IRQ %d (irqval=%d).\n",
 697			   QCASPI_DRV_NAME, qca->spi_dev->irq, ret);
 698		kthread_stop(qca->spi_thread);
 699		return ret;
 700	}
 701
 702	/* SPI thread takes care of TX queue */
 703
 704	return 0;
 705}
 706
 707static int
 708qcaspi_netdev_close(struct net_device *dev)
 709{
 710	struct qcaspi *qca = netdev_priv(dev);
 711
 712	netif_stop_queue(dev);
 713
 714	qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, 0, wr_verify);
 715	free_irq(qca->spi_dev->irq, qca);
 716
 717	kthread_stop(qca->spi_thread);
 718	qca->spi_thread = NULL;
 719	qcaspi_flush_tx_ring(qca);
 720
 721	return 0;
 722}
 723
 724static netdev_tx_t
 725qcaspi_netdev_xmit(struct sk_buff *skb, struct net_device *dev)
 726{
 727	u32 frame_len;
 728	u8 *ptmp;
 729	struct qcaspi *qca = netdev_priv(dev);
 730	u16 new_tail;
 731	struct sk_buff *tskb;
 732	u8 pad_len = 0;
 733
 734	if (skb->len < QCAFRM_MIN_LEN)
 735		pad_len = QCAFRM_MIN_LEN - skb->len;
 736
 737	if (qca->txr.skb[qca->txr.tail]) {
 738		netdev_warn(qca->net_dev, "queue was unexpectedly full!\n");
 739		netif_stop_queue(qca->net_dev);
 740		qca->stats.ring_full++;
 741		return NETDEV_TX_BUSY;
 742	}
 743
 744	if ((skb_headroom(skb) < QCAFRM_HEADER_LEN) ||
 745	    (skb_tailroom(skb) < QCAFRM_FOOTER_LEN + pad_len)) {
 746		tskb = skb_copy_expand(skb, QCAFRM_HEADER_LEN,
 747				       QCAFRM_FOOTER_LEN + pad_len, GFP_ATOMIC);
 748		if (!tskb) {
 749			qca->stats.out_of_mem++;
 750			return NETDEV_TX_BUSY;
 751		}
 752		dev_kfree_skb(skb);
 753		skb = tskb;
 754	}
 755
 756	frame_len = skb->len + pad_len;
 757
 758	ptmp = skb_push(skb, QCAFRM_HEADER_LEN);
 759	qcafrm_create_header(ptmp, frame_len);
 760
 761	if (pad_len) {
 762		ptmp = skb_put_zero(skb, pad_len);
 763	}
 764
 765	ptmp = skb_put(skb, QCAFRM_FOOTER_LEN);
 766	qcafrm_create_footer(ptmp);
 767
 768	netdev_dbg(qca->net_dev, "Tx-ing packet: Size: 0x%08x\n",
 769		   skb->len);
 770
 771	qca->txr.size += skb->len + QCASPI_HW_PKT_LEN;
 772
 773	new_tail = qca->txr.tail + 1;
 774	if (new_tail >= qca->txr.count)
 775		new_tail = 0;
 776
 777	qca->txr.skb[qca->txr.tail] = skb;
 778	qca->txr.tail = new_tail;
 779
 780	if (!qcaspi_tx_ring_has_space(&qca->txr)) {
 781		netif_stop_queue(qca->net_dev);
 782		qca->stats.ring_full++;
 783	}
 784
 785	netif_trans_update(dev);
 786
 787	if (qca->spi_thread)
 788		wake_up_process(qca->spi_thread);
 789
 790	return NETDEV_TX_OK;
 791}
 792
 793static void
 794qcaspi_netdev_tx_timeout(struct net_device *dev, unsigned int txqueue)
 795{
 796	struct qcaspi *qca = netdev_priv(dev);
 797
 798	netdev_info(qca->net_dev, "Transmit timeout at %ld, latency %ld\n",
 799		    jiffies, jiffies - dev_trans_start(dev));
 800	qca->net_dev->stats.tx_errors++;
 801	/* Trigger tx queue flush and QCA7000 reset */
 802	qca->sync = QCASPI_SYNC_UNKNOWN;
 803
 804	if (qca->spi_thread)
 805		wake_up_process(qca->spi_thread);
 806}
 807
 808static int
 809qcaspi_netdev_init(struct net_device *dev)
 810{
 811	struct qcaspi *qca = netdev_priv(dev);
 812
 813	dev->mtu = QCAFRM_MAX_MTU;
 814	dev->type = ARPHRD_ETHER;
 815	qca->clkspeed = qcaspi_clkspeed;
 816	qca->burst_len = qcaspi_burst_len;
 817	qca->spi_thread = NULL;
 818	qca->buffer_size = (dev->mtu + VLAN_ETH_HLEN + QCAFRM_HEADER_LEN +
 819		QCAFRM_FOOTER_LEN + 4) * 4;
 820
 821	memset(&qca->stats, 0, sizeof(struct qcaspi_stats));
 822
 823	qca->rx_buffer = kmalloc(qca->buffer_size, GFP_KERNEL);
 824	if (!qca->rx_buffer)
 825		return -ENOBUFS;
 826
 827	qca->rx_skb = netdev_alloc_skb_ip_align(dev, qca->net_dev->mtu +
 828						VLAN_ETH_HLEN);
 829	if (!qca->rx_skb) {
 830		kfree(qca->rx_buffer);
 831		netdev_info(qca->net_dev, "Failed to allocate RX sk_buff.\n");
 832		return -ENOBUFS;
 833	}
 834
 835	return 0;
 836}
 837
 838static void
 839qcaspi_netdev_uninit(struct net_device *dev)
 840{
 841	struct qcaspi *qca = netdev_priv(dev);
 842
 843	kfree(qca->rx_buffer);
 844	qca->buffer_size = 0;
 845	dev_kfree_skb(qca->rx_skb);
 846}
 847
 848static const struct net_device_ops qcaspi_netdev_ops = {
 849	.ndo_init = qcaspi_netdev_init,
 850	.ndo_uninit = qcaspi_netdev_uninit,
 851	.ndo_open = qcaspi_netdev_open,
 852	.ndo_stop = qcaspi_netdev_close,
 853	.ndo_start_xmit = qcaspi_netdev_xmit,
 854	.ndo_set_mac_address = eth_mac_addr,
 855	.ndo_tx_timeout = qcaspi_netdev_tx_timeout,
 856	.ndo_validate_addr = eth_validate_addr,
 857};
 858
 859static void
 860qcaspi_netdev_setup(struct net_device *dev)
 861{
 862	struct qcaspi *qca = NULL;
 863
 864	dev->netdev_ops = &qcaspi_netdev_ops;
 865	qcaspi_set_ethtool_ops(dev);
 866	dev->watchdog_timeo = QCASPI_TX_TIMEOUT;
 867	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
 868	dev->tx_queue_len = 100;
 869
 870	/* MTU range: 46 - 1500 */
 871	dev->min_mtu = QCAFRM_MIN_MTU;
 872	dev->max_mtu = QCAFRM_MAX_MTU;
 873
 874	qca = netdev_priv(dev);
 875	memset(qca, 0, sizeof(struct qcaspi));
 876
 877	memset(&qca->txr, 0, sizeof(qca->txr));
 878	qca->txr.count = TX_RING_MAX_LEN;
 879}
 880
 881static const struct of_device_id qca_spi_of_match[] = {
 882	{ .compatible = "qca,qca7000" },
 883	{ /* sentinel */ }
 884};
 885MODULE_DEVICE_TABLE(of, qca_spi_of_match);
 886
 887static int
 888qca_spi_probe(struct spi_device *spi)
 889{
 890	struct qcaspi *qca = NULL;
 891	struct net_device *qcaspi_devs = NULL;
 892	u8 legacy_mode = 0;
 893	u16 signature;
 894	int ret;
 895
 896	if (!spi->dev.of_node) {
 897		dev_err(&spi->dev, "Missing device tree\n");
 898		return -EINVAL;
 899	}
 900
 901	legacy_mode = of_property_read_bool(spi->dev.of_node,
 902					    "qca,legacy-mode");
 903
 904	if (qcaspi_clkspeed == 0) {
 905		if (spi->max_speed_hz)
 906			qcaspi_clkspeed = spi->max_speed_hz;
 907		else
 908			qcaspi_clkspeed = QCASPI_CLK_SPEED;
 909	}
 910
 911	if ((qcaspi_clkspeed < QCASPI_CLK_SPEED_MIN) ||
 912	    (qcaspi_clkspeed > QCASPI_CLK_SPEED_MAX)) {
 913		dev_err(&spi->dev, "Invalid clkspeed: %d\n",
 914			qcaspi_clkspeed);
 915		return -EINVAL;
 916	}
 917
 918	if ((qcaspi_burst_len < QCASPI_BURST_LEN_MIN) ||
 919	    (qcaspi_burst_len > QCASPI_BURST_LEN_MAX)) {
 920		dev_err(&spi->dev, "Invalid burst len: %d\n",
 921			qcaspi_burst_len);
 922		return -EINVAL;
 923	}
 924
 925	if ((qcaspi_pluggable < QCASPI_PLUGGABLE_MIN) ||
 926	    (qcaspi_pluggable > QCASPI_PLUGGABLE_MAX)) {
 927		dev_err(&spi->dev, "Invalid pluggable: %d\n",
 928			qcaspi_pluggable);
 929		return -EINVAL;
 930	}
 931
 932	if (wr_verify < QCASPI_WRITE_VERIFY_MIN ||
 933	    wr_verify > QCASPI_WRITE_VERIFY_MAX) {
 934		dev_err(&spi->dev, "Invalid write verify: %d\n",
 935			wr_verify);
 936		return -EINVAL;
 937	}
 938
 939	dev_info(&spi->dev, "ver=%s, clkspeed=%d, burst_len=%d, pluggable=%d\n",
 940		 QCASPI_DRV_VERSION,
 941		 qcaspi_clkspeed,
 942		 qcaspi_burst_len,
 943		 qcaspi_pluggable);
 944
 945	spi->mode = SPI_MODE_3;
 946	spi->max_speed_hz = qcaspi_clkspeed;
 947	if (spi_setup(spi) < 0) {
 948		dev_err(&spi->dev, "Unable to setup SPI device\n");
 949		return -EFAULT;
 950	}
 951
 952	qcaspi_devs = alloc_etherdev(sizeof(struct qcaspi));
 953	if (!qcaspi_devs)
 954		return -ENOMEM;
 955
 956	qcaspi_netdev_setup(qcaspi_devs);
 957	SET_NETDEV_DEV(qcaspi_devs, &spi->dev);
 958
 959	qca = netdev_priv(qcaspi_devs);
 960	if (!qca) {
 961		free_netdev(qcaspi_devs);
 962		dev_err(&spi->dev, "Fail to retrieve private structure\n");
 963		return -ENOMEM;
 964	}
 965	qca->net_dev = qcaspi_devs;
 966	qca->spi_dev = spi;
 967	qca->legacy_mode = legacy_mode;
 968
 969	spi_set_drvdata(spi, qcaspi_devs);
 970
 971	ret = of_get_ethdev_address(spi->dev.of_node, qca->net_dev);
 972	if (ret) {
 973		eth_hw_addr_random(qca->net_dev);
 974		dev_info(&spi->dev, "Using random MAC address: %pM\n",
 975			 qca->net_dev->dev_addr);
 976	}
 977
 978	netif_carrier_off(qca->net_dev);
 979
 980	if (!qcaspi_pluggable) {
 981		qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
 982		qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
 983
 984		if (signature != QCASPI_GOOD_SIGNATURE) {
 985			dev_err(&spi->dev, "Invalid signature (0x%04X)\n",
 986				signature);
 987			free_netdev(qcaspi_devs);
 988			return -EFAULT;
 989		}
 990	}
 991
 992	if (register_netdev(qcaspi_devs)) {
 993		dev_err(&spi->dev, "Unable to register net device %s\n",
 994			qcaspi_devs->name);
 995		free_netdev(qcaspi_devs);
 996		return -EFAULT;
 997	}
 998
 999	qcaspi_init_device_debugfs(qca);
1000
1001	return 0;
1002}
1003
1004static void
1005qca_spi_remove(struct spi_device *spi)
1006{
1007	struct net_device *qcaspi_devs = spi_get_drvdata(spi);
1008	struct qcaspi *qca = netdev_priv(qcaspi_devs);
1009
1010	qcaspi_remove_device_debugfs(qca);
1011
1012	unregister_netdev(qcaspi_devs);
1013	free_netdev(qcaspi_devs);
1014}
1015
1016static const struct spi_device_id qca_spi_id[] = {
1017	{ "qca7000", 0 },
1018	{ /* sentinel */ }
1019};
1020MODULE_DEVICE_TABLE(spi, qca_spi_id);
1021
1022static struct spi_driver qca_spi_driver = {
1023	.driver	= {
1024		.name	= QCASPI_DRV_NAME,
1025		.of_match_table = qca_spi_of_match,
1026	},
1027	.id_table = qca_spi_id,
1028	.probe    = qca_spi_probe,
1029	.remove   = qca_spi_remove,
1030};
1031module_spi_driver(qca_spi_driver);
1032
1033MODULE_DESCRIPTION("Qualcomm Atheros QCA7000 SPI Driver");
1034MODULE_AUTHOR("Qualcomm Atheros Communications");
1035MODULE_AUTHOR("Stefan Wahren <stefan.wahren@i2se.com>");
1036MODULE_LICENSE("Dual BSD/GPL");
1037MODULE_VERSION(QCASPI_DRV_VERSION);