xref: /openbmc/linux/drivers/net/wan/fsl_ucc_hdlc.c (revision 6e6c61d3)
1 /* Freescale QUICC Engine HDLC Device Driver
2  *
3  * Copyright 2016 Freescale Semiconductor Inc.
4  *
5  * This program is free software; you can redistribute  it and/or modify it
6  * under  the terms of  the GNU General  Public License as published by the
7  * Free Software Foundation;  either version 2 of the  License, or (at your
8  * option) any later version.
9  */
10 
11 #include <linux/delay.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/hdlc.h>
14 #include <linux/init.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/irq.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/netdevice.h>
21 #include <linux/of_address.h>
22 #include <linux/of_irq.h>
23 #include <linux/of_platform.h>
24 #include <linux/platform_device.h>
25 #include <linux/sched.h>
26 #include <linux/skbuff.h>
27 #include <linux/slab.h>
28 #include <linux/spinlock.h>
29 #include <linux/stddef.h>
30 #include <soc/fsl/qe/qe_tdm.h>
31 #include <uapi/linux/if_arp.h>
32 
33 #include "fsl_ucc_hdlc.h"
34 
35 #define DRV_DESC "Freescale QE UCC HDLC Driver"
36 #define DRV_NAME "ucc_hdlc"
37 
38 #define TDM_PPPOHT_SLIC_MAXIN
39 #define RX_BD_ERRORS (R_CD_S | R_OV_S | R_CR_S | R_AB_S | R_NO_S | R_LG_S)
40 
41 static struct ucc_tdm_info utdm_primary_info = {
42 	.uf_info = {
43 		.tsa = 0,
44 		.cdp = 0,
45 		.cds = 1,
46 		.ctsp = 1,
47 		.ctss = 1,
48 		.revd = 0,
49 		.urfs = 256,
50 		.utfs = 256,
51 		.urfet = 128,
52 		.urfset = 192,
53 		.utfet = 128,
54 		.utftt = 0x40,
55 		.ufpt = 256,
56 		.mode = UCC_FAST_PROTOCOL_MODE_HDLC,
57 		.ttx_trx = UCC_FAST_GUMR_TRANSPARENT_TTX_TRX_NORMAL,
58 		.tenc = UCC_FAST_TX_ENCODING_NRZ,
59 		.renc = UCC_FAST_RX_ENCODING_NRZ,
60 		.tcrc = UCC_FAST_16_BIT_CRC,
61 		.synl = UCC_FAST_SYNC_LEN_NOT_USED,
62 	},
63 
64 	.si_info = {
65 #ifdef TDM_PPPOHT_SLIC_MAXIN
66 		.simr_rfsd = 1,
67 		.simr_tfsd = 2,
68 #else
69 		.simr_rfsd = 0,
70 		.simr_tfsd = 0,
71 #endif
72 		.simr_crt = 0,
73 		.simr_sl = 0,
74 		.simr_ce = 1,
75 		.simr_fe = 1,
76 		.simr_gm = 0,
77 	},
78 };
79 
80 static struct ucc_tdm_info utdm_info[MAX_HDLC_NUM];
81 
82 static int uhdlc_init(struct ucc_hdlc_private *priv)
83 {
84 	struct ucc_tdm_info *ut_info;
85 	struct ucc_fast_info *uf_info;
86 	u32 cecr_subblock;
87 	u16 bd_status;
88 	int ret, i;
89 	void *bd_buffer;
90 	dma_addr_t bd_dma_addr;
91 	u32 riptr;
92 	u32 tiptr;
93 	u32 gumr;
94 
95 	ut_info = priv->ut_info;
96 	uf_info = &ut_info->uf_info;
97 
98 	if (priv->tsa) {
99 		uf_info->tsa = 1;
100 		uf_info->ctsp = 1;
101 		uf_info->cds = 1;
102 		uf_info->ctss = 1;
103 	} else {
104 		uf_info->cds = 0;
105 		uf_info->ctsp = 0;
106 		uf_info->ctss = 0;
107 	}
108 
109 	/* This sets HPM register in CMXUCR register which configures a
110 	 * open drain connected HDLC bus
111 	 */
112 	if (priv->hdlc_bus)
113 		uf_info->brkpt_support = 1;
114 
115 	uf_info->uccm_mask = ((UCC_HDLC_UCCE_RXB | UCC_HDLC_UCCE_RXF |
116 				UCC_HDLC_UCCE_TXB) << 16);
117 
118 	ret = ucc_fast_init(uf_info, &priv->uccf);
119 	if (ret) {
120 		dev_err(priv->dev, "Failed to init uccf.");
121 		return ret;
122 	}
123 
124 	priv->uf_regs = priv->uccf->uf_regs;
125 	ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
126 
127 	/* Loopback mode */
128 	if (priv->loopback) {
129 		dev_info(priv->dev, "Loopback Mode\n");
130 		/* use the same clock when work in loopback */
131 		qe_setbrg(ut_info->uf_info.rx_clock, 20000000, 1);
132 
133 		gumr = ioread32be(&priv->uf_regs->gumr);
134 		gumr |= (UCC_FAST_GUMR_LOOPBACK | UCC_FAST_GUMR_CDS |
135 			 UCC_FAST_GUMR_TCI);
136 		gumr &= ~(UCC_FAST_GUMR_CTSP | UCC_FAST_GUMR_RSYN);
137 		iowrite32be(gumr, &priv->uf_regs->gumr);
138 	}
139 
140 	/* Initialize SI */
141 	if (priv->tsa)
142 		ucc_tdm_init(priv->utdm, priv->ut_info);
143 
144 	/* Write to QE CECR, UCCx channel to Stop Transmission */
145 	cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
146 	ret = qe_issue_cmd(QE_STOP_TX, cecr_subblock,
147 			   QE_CR_PROTOCOL_UNSPECIFIED, 0);
148 
149 	/* Set UPSMR normal mode (need fixed)*/
150 	iowrite32be(0, &priv->uf_regs->upsmr);
151 
152 	/* hdlc_bus mode */
153 	if (priv->hdlc_bus) {
154 		u32 upsmr;
155 
156 		dev_info(priv->dev, "HDLC bus Mode\n");
157 		upsmr = ioread32be(&priv->uf_regs->upsmr);
158 
159 		/* bus mode and retransmit enable, with collision window
160 		 * set to 8 bytes
161 		 */
162 		upsmr |= UCC_HDLC_UPSMR_RTE | UCC_HDLC_UPSMR_BUS |
163 				UCC_HDLC_UPSMR_CW8;
164 		iowrite32be(upsmr, &priv->uf_regs->upsmr);
165 
166 		/* explicitly disable CDS & CTSP */
167 		gumr = ioread32be(&priv->uf_regs->gumr);
168 		gumr &= ~(UCC_FAST_GUMR_CDS | UCC_FAST_GUMR_CTSP);
169 		/* set automatic sync to explicitly ignore CD signal */
170 		gumr |= UCC_FAST_GUMR_SYNL_AUTO;
171 		iowrite32be(gumr, &priv->uf_regs->gumr);
172 	}
173 
174 	priv->rx_ring_size = RX_BD_RING_LEN;
175 	priv->tx_ring_size = TX_BD_RING_LEN;
176 	/* Alloc Rx BD */
177 	priv->rx_bd_base = dma_alloc_coherent(priv->dev,
178 			RX_BD_RING_LEN * sizeof(struct qe_bd),
179 			&priv->dma_rx_bd, GFP_KERNEL);
180 
181 	if (!priv->rx_bd_base) {
182 		dev_err(priv->dev, "Cannot allocate MURAM memory for RxBDs\n");
183 		ret = -ENOMEM;
184 		goto free_uccf;
185 	}
186 
187 	/* Alloc Tx BD */
188 	priv->tx_bd_base = dma_alloc_coherent(priv->dev,
189 			TX_BD_RING_LEN * sizeof(struct qe_bd),
190 			&priv->dma_tx_bd, GFP_KERNEL);
191 
192 	if (!priv->tx_bd_base) {
193 		dev_err(priv->dev, "Cannot allocate MURAM memory for TxBDs\n");
194 		ret = -ENOMEM;
195 		goto free_rx_bd;
196 	}
197 
198 	/* Alloc parameter ram for ucc hdlc */
199 	priv->ucc_pram_offset = qe_muram_alloc(sizeof(struct ucc_hdlc_param),
200 				ALIGNMENT_OF_UCC_HDLC_PRAM);
201 
202 	if (IS_ERR_VALUE(priv->ucc_pram_offset)) {
203 		dev_err(priv->dev, "Can not allocate MURAM for hdlc parameter.\n");
204 		ret = -ENOMEM;
205 		goto free_tx_bd;
206 	}
207 
208 	priv->rx_skbuff = kcalloc(priv->rx_ring_size,
209 				  sizeof(*priv->rx_skbuff),
210 				  GFP_KERNEL);
211 	if (!priv->rx_skbuff)
212 		goto free_ucc_pram;
213 
214 	priv->tx_skbuff = kcalloc(priv->tx_ring_size,
215 				  sizeof(*priv->tx_skbuff),
216 				  GFP_KERNEL);
217 	if (!priv->tx_skbuff)
218 		goto free_rx_skbuff;
219 
220 	priv->skb_curtx = 0;
221 	priv->skb_dirtytx = 0;
222 	priv->curtx_bd = priv->tx_bd_base;
223 	priv->dirty_tx = priv->tx_bd_base;
224 	priv->currx_bd = priv->rx_bd_base;
225 	priv->currx_bdnum = 0;
226 
227 	/* init parameter base */
228 	cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
229 	ret = qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, cecr_subblock,
230 			   QE_CR_PROTOCOL_UNSPECIFIED, priv->ucc_pram_offset);
231 
232 	priv->ucc_pram = (struct ucc_hdlc_param __iomem *)
233 					qe_muram_addr(priv->ucc_pram_offset);
234 
235 	/* Zero out parameter ram */
236 	memset_io(priv->ucc_pram, 0, sizeof(struct ucc_hdlc_param));
237 
238 	/* Alloc riptr, tiptr */
239 	riptr = qe_muram_alloc(32, 32);
240 	if (IS_ERR_VALUE(riptr)) {
241 		dev_err(priv->dev, "Cannot allocate MURAM mem for Receive internal temp data pointer\n");
242 		ret = -ENOMEM;
243 		goto free_tx_skbuff;
244 	}
245 
246 	tiptr = qe_muram_alloc(32, 32);
247 	if (IS_ERR_VALUE(tiptr)) {
248 		dev_err(priv->dev, "Cannot allocate MURAM mem for Transmit internal temp data pointer\n");
249 		ret = -ENOMEM;
250 		goto free_riptr;
251 	}
252 
253 	/* Set RIPTR, TIPTR */
254 	iowrite16be(riptr, &priv->ucc_pram->riptr);
255 	iowrite16be(tiptr, &priv->ucc_pram->tiptr);
256 
257 	/* Set MRBLR */
258 	iowrite16be(MAX_RX_BUF_LENGTH, &priv->ucc_pram->mrblr);
259 
260 	/* Set RBASE, TBASE */
261 	iowrite32be(priv->dma_rx_bd, &priv->ucc_pram->rbase);
262 	iowrite32be(priv->dma_tx_bd, &priv->ucc_pram->tbase);
263 
264 	/* Set RSTATE, TSTATE */
265 	iowrite32be(BMR_GBL | BMR_BIG_ENDIAN, &priv->ucc_pram->rstate);
266 	iowrite32be(BMR_GBL | BMR_BIG_ENDIAN, &priv->ucc_pram->tstate);
267 
268 	/* Set C_MASK, C_PRES for 16bit CRC */
269 	iowrite32be(CRC_16BIT_MASK, &priv->ucc_pram->c_mask);
270 	iowrite32be(CRC_16BIT_PRES, &priv->ucc_pram->c_pres);
271 
272 	iowrite16be(MAX_FRAME_LENGTH, &priv->ucc_pram->mflr);
273 	iowrite16be(DEFAULT_RFTHR, &priv->ucc_pram->rfthr);
274 	iowrite16be(DEFAULT_RFTHR, &priv->ucc_pram->rfcnt);
275 	iowrite16be(priv->hmask, &priv->ucc_pram->hmask);
276 	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr1);
277 	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr2);
278 	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr3);
279 	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr4);
280 
281 	/* Get BD buffer */
282 	bd_buffer = dma_zalloc_coherent(priv->dev,
283 					(RX_BD_RING_LEN + TX_BD_RING_LEN) *
284 					MAX_RX_BUF_LENGTH,
285 					&bd_dma_addr, GFP_KERNEL);
286 
287 	if (!bd_buffer) {
288 		dev_err(priv->dev, "Could not allocate buffer descriptors\n");
289 		ret = -ENOMEM;
290 		goto free_tiptr;
291 	}
292 
293 	priv->rx_buffer = bd_buffer;
294 	priv->tx_buffer = bd_buffer + RX_BD_RING_LEN * MAX_RX_BUF_LENGTH;
295 
296 	priv->dma_rx_addr = bd_dma_addr;
297 	priv->dma_tx_addr = bd_dma_addr + RX_BD_RING_LEN * MAX_RX_BUF_LENGTH;
298 
299 	for (i = 0; i < RX_BD_RING_LEN; i++) {
300 		if (i < (RX_BD_RING_LEN - 1))
301 			bd_status = R_E_S | R_I_S;
302 		else
303 			bd_status = R_E_S | R_I_S | R_W_S;
304 
305 		iowrite16be(bd_status, &priv->rx_bd_base[i].status);
306 		iowrite32be(priv->dma_rx_addr + i * MAX_RX_BUF_LENGTH,
307 			    &priv->rx_bd_base[i].buf);
308 	}
309 
310 	for (i = 0; i < TX_BD_RING_LEN; i++) {
311 		if (i < (TX_BD_RING_LEN - 1))
312 			bd_status =  T_I_S | T_TC_S;
313 		else
314 			bd_status =  T_I_S | T_TC_S | T_W_S;
315 
316 		iowrite16be(bd_status, &priv->tx_bd_base[i].status);
317 		iowrite32be(priv->dma_tx_addr + i * MAX_RX_BUF_LENGTH,
318 			    &priv->tx_bd_base[i].buf);
319 	}
320 
321 	return 0;
322 
323 free_tiptr:
324 	qe_muram_free(tiptr);
325 free_riptr:
326 	qe_muram_free(riptr);
327 free_tx_skbuff:
328 	kfree(priv->tx_skbuff);
329 free_rx_skbuff:
330 	kfree(priv->rx_skbuff);
331 free_ucc_pram:
332 	qe_muram_free(priv->ucc_pram_offset);
333 free_tx_bd:
334 	dma_free_coherent(priv->dev,
335 			  TX_BD_RING_LEN * sizeof(struct qe_bd),
336 			  priv->tx_bd_base, priv->dma_tx_bd);
337 free_rx_bd:
338 	dma_free_coherent(priv->dev,
339 			  RX_BD_RING_LEN * sizeof(struct qe_bd),
340 			  priv->rx_bd_base, priv->dma_rx_bd);
341 free_uccf:
342 	ucc_fast_free(priv->uccf);
343 
344 	return ret;
345 }
346 
347 static netdev_tx_t ucc_hdlc_tx(struct sk_buff *skb, struct net_device *dev)
348 {
349 	hdlc_device *hdlc = dev_to_hdlc(dev);
350 	struct ucc_hdlc_private *priv = (struct ucc_hdlc_private *)hdlc->priv;
351 	struct qe_bd __iomem *bd;
352 	u16 bd_status;
353 	unsigned long flags;
354 	u16 *proto_head;
355 
356 	switch (dev->type) {
357 	case ARPHRD_RAWHDLC:
358 		if (skb_headroom(skb) < HDLC_HEAD_LEN) {
359 			dev->stats.tx_dropped++;
360 			dev_kfree_skb(skb);
361 			netdev_err(dev, "No enough space for hdlc head\n");
362 			return -ENOMEM;
363 		}
364 
365 		skb_push(skb, HDLC_HEAD_LEN);
366 
367 		proto_head = (u16 *)skb->data;
368 		*proto_head = htons(DEFAULT_HDLC_HEAD);
369 
370 		dev->stats.tx_bytes += skb->len;
371 		break;
372 
373 	case ARPHRD_PPP:
374 		proto_head = (u16 *)skb->data;
375 		if (*proto_head != htons(DEFAULT_PPP_HEAD)) {
376 			dev->stats.tx_dropped++;
377 			dev_kfree_skb(skb);
378 			netdev_err(dev, "Wrong ppp header\n");
379 			return -ENOMEM;
380 		}
381 
382 		dev->stats.tx_bytes += skb->len;
383 		break;
384 
385 	case ARPHRD_ETHER:
386 		dev->stats.tx_bytes += skb->len;
387 		break;
388 
389 	default:
390 		dev->stats.tx_dropped++;
391 		dev_kfree_skb(skb);
392 		return -ENOMEM;
393 	}
394 	netdev_sent_queue(dev, skb->len);
395 	spin_lock_irqsave(&priv->lock, flags);
396 
397 	/* Start from the next BD that should be filled */
398 	bd = priv->curtx_bd;
399 	bd_status = ioread16be(&bd->status);
400 	/* Save the skb pointer so we can free it later */
401 	priv->tx_skbuff[priv->skb_curtx] = skb;
402 
403 	/* Update the current skb pointer (wrapping if this was the last) */
404 	priv->skb_curtx =
405 	    (priv->skb_curtx + 1) & TX_RING_MOD_MASK(TX_BD_RING_LEN);
406 
407 	/* copy skb data to tx buffer for sdma processing */
408 	memcpy(priv->tx_buffer + (be32_to_cpu(bd->buf) - priv->dma_tx_addr),
409 	       skb->data, skb->len);
410 
411 	/* set bd status and length */
412 	bd_status = (bd_status & T_W_S) | T_R_S | T_I_S | T_L_S | T_TC_S;
413 
414 	iowrite16be(skb->len, &bd->length);
415 	iowrite16be(bd_status, &bd->status);
416 
417 	/* Move to next BD in the ring */
418 	if (!(bd_status & T_W_S))
419 		bd += 1;
420 	else
421 		bd = priv->tx_bd_base;
422 
423 	if (bd == priv->dirty_tx) {
424 		if (!netif_queue_stopped(dev))
425 			netif_stop_queue(dev);
426 	}
427 
428 	priv->curtx_bd = bd;
429 
430 	spin_unlock_irqrestore(&priv->lock, flags);
431 
432 	return NETDEV_TX_OK;
433 }
434 
435 static int hdlc_tx_restart(struct ucc_hdlc_private *priv)
436 {
437 	u32 cecr_subblock;
438 
439 	cecr_subblock =
440 		ucc_fast_get_qe_cr_subblock(priv->ut_info->uf_info.ucc_num);
441 
442 	qe_issue_cmd(QE_RESTART_TX, cecr_subblock,
443 		     QE_CR_PROTOCOL_UNSPECIFIED, 0);
444 	return 0;
445 }
446 
447 static int hdlc_tx_done(struct ucc_hdlc_private *priv)
448 {
449 	/* Start from the next BD that should be filled */
450 	struct net_device *dev = priv->ndev;
451 	unsigned int bytes_sent = 0;
452 	int howmany = 0;
453 	struct qe_bd *bd;		/* BD pointer */
454 	u16 bd_status;
455 	int tx_restart = 0;
456 
457 	bd = priv->dirty_tx;
458 	bd_status = ioread16be(&bd->status);
459 
460 	/* Normal processing. */
461 	while ((bd_status & T_R_S) == 0) {
462 		struct sk_buff *skb;
463 
464 		if (bd_status & T_UN_S) { /* Underrun */
465 			dev->stats.tx_fifo_errors++;
466 			tx_restart = 1;
467 		}
468 		if (bd_status & T_CT_S) { /* Carrier lost */
469 			dev->stats.tx_carrier_errors++;
470 			tx_restart = 1;
471 		}
472 
473 		/* BD contains already transmitted buffer.   */
474 		/* Handle the transmitted buffer and release */
475 		/* the BD to be used with the current frame  */
476 
477 		skb = priv->tx_skbuff[priv->skb_dirtytx];
478 		if (!skb)
479 			break;
480 		howmany++;
481 		bytes_sent += skb->len;
482 		dev->stats.tx_packets++;
483 		memset(priv->tx_buffer +
484 		       (be32_to_cpu(bd->buf) - priv->dma_tx_addr),
485 		       0, skb->len);
486 		dev_kfree_skb_irq(skb);
487 
488 		priv->tx_skbuff[priv->skb_dirtytx] = NULL;
489 		priv->skb_dirtytx =
490 		    (priv->skb_dirtytx +
491 		     1) & TX_RING_MOD_MASK(TX_BD_RING_LEN);
492 
493 		/* We freed a buffer, so now we can restart transmission */
494 		if (netif_queue_stopped(dev))
495 			netif_wake_queue(dev);
496 
497 		/* Advance the confirmation BD pointer */
498 		if (!(bd_status & T_W_S))
499 			bd += 1;
500 		else
501 			bd = priv->tx_bd_base;
502 		bd_status = ioread16be(&bd->status);
503 	}
504 	priv->dirty_tx = bd;
505 
506 	if (tx_restart)
507 		hdlc_tx_restart(priv);
508 
509 	netdev_completed_queue(dev, howmany, bytes_sent);
510 	return 0;
511 }
512 
513 static int hdlc_rx_done(struct ucc_hdlc_private *priv, int rx_work_limit)
514 {
515 	struct net_device *dev = priv->ndev;
516 	struct sk_buff *skb = NULL;
517 	hdlc_device *hdlc = dev_to_hdlc(dev);
518 	struct qe_bd *bd;
519 	u16 bd_status;
520 	u16 length, howmany = 0;
521 	u8 *bdbuffer;
522 
523 	bd = priv->currx_bd;
524 	bd_status = ioread16be(&bd->status);
525 
526 	/* while there are received buffers and BD is full (~R_E) */
527 	while (!((bd_status & (R_E_S)) || (--rx_work_limit < 0))) {
528 		if (bd_status & (RX_BD_ERRORS)) {
529 			dev->stats.rx_errors++;
530 
531 			if (bd_status & R_CD_S)
532 				dev->stats.collisions++;
533 			if (bd_status & R_OV_S)
534 				dev->stats.rx_fifo_errors++;
535 			if (bd_status & R_CR_S)
536 				dev->stats.rx_crc_errors++;
537 			if (bd_status & R_AB_S)
538 				dev->stats.rx_over_errors++;
539 			if (bd_status & R_NO_S)
540 				dev->stats.rx_frame_errors++;
541 			if (bd_status & R_LG_S)
542 				dev->stats.rx_length_errors++;
543 
544 			goto recycle;
545 		}
546 		bdbuffer = priv->rx_buffer +
547 			(priv->currx_bdnum * MAX_RX_BUF_LENGTH);
548 		length = ioread16be(&bd->length);
549 
550 		switch (dev->type) {
551 		case ARPHRD_RAWHDLC:
552 			bdbuffer += HDLC_HEAD_LEN;
553 			length -= (HDLC_HEAD_LEN + HDLC_CRC_SIZE);
554 
555 			skb = dev_alloc_skb(length);
556 			if (!skb) {
557 				dev->stats.rx_dropped++;
558 				return -ENOMEM;
559 			}
560 
561 			skb_put(skb, length);
562 			skb->len = length;
563 			skb->dev = dev;
564 			memcpy(skb->data, bdbuffer, length);
565 			break;
566 
567 		case ARPHRD_PPP:
568 		case ARPHRD_ETHER:
569 			length -= HDLC_CRC_SIZE;
570 
571 			skb = dev_alloc_skb(length);
572 			if (!skb) {
573 				dev->stats.rx_dropped++;
574 				return -ENOMEM;
575 			}
576 
577 			skb_put(skb, length);
578 			skb->len = length;
579 			skb->dev = dev;
580 			memcpy(skb->data, bdbuffer, length);
581 			break;
582 		}
583 
584 		dev->stats.rx_packets++;
585 		dev->stats.rx_bytes += skb->len;
586 		howmany++;
587 		if (hdlc->proto)
588 			skb->protocol = hdlc_type_trans(skb, dev);
589 		netif_receive_skb(skb);
590 
591 recycle:
592 		iowrite16be((bd_status & R_W_S) | R_E_S | R_I_S, &bd->status);
593 
594 		/* update to point at the next bd */
595 		if (bd_status & R_W_S) {
596 			priv->currx_bdnum = 0;
597 			bd = priv->rx_bd_base;
598 		} else {
599 			if (priv->currx_bdnum < (RX_BD_RING_LEN - 1))
600 				priv->currx_bdnum += 1;
601 			else
602 				priv->currx_bdnum = RX_BD_RING_LEN - 1;
603 
604 			bd += 1;
605 		}
606 
607 		bd_status = ioread16be(&bd->status);
608 	}
609 
610 	priv->currx_bd = bd;
611 	return howmany;
612 }
613 
614 static int ucc_hdlc_poll(struct napi_struct *napi, int budget)
615 {
616 	struct ucc_hdlc_private *priv = container_of(napi,
617 						     struct ucc_hdlc_private,
618 						     napi);
619 	int howmany;
620 
621 	/* Tx event processing */
622 	spin_lock(&priv->lock);
623 	hdlc_tx_done(priv);
624 	spin_unlock(&priv->lock);
625 
626 	howmany = 0;
627 	howmany += hdlc_rx_done(priv, budget - howmany);
628 
629 	if (howmany < budget) {
630 		napi_complete_done(napi, howmany);
631 		qe_setbits32(priv->uccf->p_uccm,
632 			     (UCCE_HDLC_RX_EVENTS | UCCE_HDLC_TX_EVENTS) << 16);
633 	}
634 
635 	return howmany;
636 }
637 
638 static irqreturn_t ucc_hdlc_irq_handler(int irq, void *dev_id)
639 {
640 	struct ucc_hdlc_private *priv = (struct ucc_hdlc_private *)dev_id;
641 	struct net_device *dev = priv->ndev;
642 	struct ucc_fast_private *uccf;
643 	struct ucc_tdm_info *ut_info;
644 	u32 ucce;
645 	u32 uccm;
646 
647 	ut_info = priv->ut_info;
648 	uccf = priv->uccf;
649 
650 	ucce = ioread32be(uccf->p_ucce);
651 	uccm = ioread32be(uccf->p_uccm);
652 	ucce &= uccm;
653 	iowrite32be(ucce, uccf->p_ucce);
654 	if (!ucce)
655 		return IRQ_NONE;
656 
657 	if ((ucce >> 16) & (UCCE_HDLC_RX_EVENTS | UCCE_HDLC_TX_EVENTS)) {
658 		if (napi_schedule_prep(&priv->napi)) {
659 			uccm &= ~((UCCE_HDLC_RX_EVENTS | UCCE_HDLC_TX_EVENTS)
660 				  << 16);
661 			iowrite32be(uccm, uccf->p_uccm);
662 			__napi_schedule(&priv->napi);
663 		}
664 	}
665 
666 	/* Errors and other events */
667 	if (ucce >> 16 & UCC_HDLC_UCCE_BSY)
668 		dev->stats.rx_missed_errors++;
669 	if (ucce >> 16 & UCC_HDLC_UCCE_TXE)
670 		dev->stats.tx_errors++;
671 
672 	return IRQ_HANDLED;
673 }
674 
675 static int uhdlc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
676 {
677 	const size_t size = sizeof(te1_settings);
678 	te1_settings line;
679 	struct ucc_hdlc_private *priv = netdev_priv(dev);
680 
681 	if (cmd != SIOCWANDEV)
682 		return hdlc_ioctl(dev, ifr, cmd);
683 
684 	switch (ifr->ifr_settings.type) {
685 	case IF_GET_IFACE:
686 		ifr->ifr_settings.type = IF_IFACE_E1;
687 		if (ifr->ifr_settings.size < size) {
688 			ifr->ifr_settings.size = size; /* data size wanted */
689 			return -ENOBUFS;
690 		}
691 		memset(&line, 0, sizeof(line));
692 		line.clock_type = priv->clocking;
693 
694 		if (copy_to_user(ifr->ifr_settings.ifs_ifsu.sync, &line, size))
695 			return -EFAULT;
696 		return 0;
697 
698 	default:
699 		return hdlc_ioctl(dev, ifr, cmd);
700 	}
701 }
702 
703 static int uhdlc_open(struct net_device *dev)
704 {
705 	u32 cecr_subblock;
706 	hdlc_device *hdlc = dev_to_hdlc(dev);
707 	struct ucc_hdlc_private *priv = hdlc->priv;
708 	struct ucc_tdm *utdm = priv->utdm;
709 
710 	if (priv->hdlc_busy != 1) {
711 		if (request_irq(priv->ut_info->uf_info.irq,
712 				ucc_hdlc_irq_handler, 0, "hdlc", priv))
713 			return -ENODEV;
714 
715 		cecr_subblock = ucc_fast_get_qe_cr_subblock(
716 					priv->ut_info->uf_info.ucc_num);
717 
718 		qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
719 			     QE_CR_PROTOCOL_UNSPECIFIED, 0);
720 
721 		ucc_fast_enable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
722 
723 		/* Enable the TDM port */
724 		if (priv->tsa)
725 			utdm->si_regs->siglmr1_h |= (0x1 << utdm->tdm_port);
726 
727 		priv->hdlc_busy = 1;
728 		netif_device_attach(priv->ndev);
729 		napi_enable(&priv->napi);
730 		netdev_reset_queue(dev);
731 		netif_start_queue(dev);
732 		hdlc_open(dev);
733 	}
734 
735 	return 0;
736 }
737 
738 static void uhdlc_memclean(struct ucc_hdlc_private *priv)
739 {
740 	qe_muram_free(priv->ucc_pram->riptr);
741 	qe_muram_free(priv->ucc_pram->tiptr);
742 
743 	if (priv->rx_bd_base) {
744 		dma_free_coherent(priv->dev,
745 				  RX_BD_RING_LEN * sizeof(struct qe_bd),
746 				  priv->rx_bd_base, priv->dma_rx_bd);
747 
748 		priv->rx_bd_base = NULL;
749 		priv->dma_rx_bd = 0;
750 	}
751 
752 	if (priv->tx_bd_base) {
753 		dma_free_coherent(priv->dev,
754 				  TX_BD_RING_LEN * sizeof(struct qe_bd),
755 				  priv->tx_bd_base, priv->dma_tx_bd);
756 
757 		priv->tx_bd_base = NULL;
758 		priv->dma_tx_bd = 0;
759 	}
760 
761 	if (priv->ucc_pram) {
762 		qe_muram_free(priv->ucc_pram_offset);
763 		priv->ucc_pram = NULL;
764 		priv->ucc_pram_offset = 0;
765 	 }
766 
767 	kfree(priv->rx_skbuff);
768 	priv->rx_skbuff = NULL;
769 
770 	kfree(priv->tx_skbuff);
771 	priv->tx_skbuff = NULL;
772 
773 	if (priv->uf_regs) {
774 		iounmap(priv->uf_regs);
775 		priv->uf_regs = NULL;
776 	}
777 
778 	if (priv->uccf) {
779 		ucc_fast_free(priv->uccf);
780 		priv->uccf = NULL;
781 	}
782 
783 	if (priv->rx_buffer) {
784 		dma_free_coherent(priv->dev,
785 				  RX_BD_RING_LEN * MAX_RX_BUF_LENGTH,
786 				  priv->rx_buffer, priv->dma_rx_addr);
787 		priv->rx_buffer = NULL;
788 		priv->dma_rx_addr = 0;
789 	}
790 
791 	if (priv->tx_buffer) {
792 		dma_free_coherent(priv->dev,
793 				  TX_BD_RING_LEN * MAX_RX_BUF_LENGTH,
794 				  priv->tx_buffer, priv->dma_tx_addr);
795 		priv->tx_buffer = NULL;
796 		priv->dma_tx_addr = 0;
797 	}
798 }
799 
800 static int uhdlc_close(struct net_device *dev)
801 {
802 	struct ucc_hdlc_private *priv = dev_to_hdlc(dev)->priv;
803 	struct ucc_tdm *utdm = priv->utdm;
804 	u32 cecr_subblock;
805 
806 	napi_disable(&priv->napi);
807 	cecr_subblock = ucc_fast_get_qe_cr_subblock(
808 				priv->ut_info->uf_info.ucc_num);
809 
810 	qe_issue_cmd(QE_GRACEFUL_STOP_TX, cecr_subblock,
811 		     (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
812 	qe_issue_cmd(QE_CLOSE_RX_BD, cecr_subblock,
813 		     (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
814 
815 	if (priv->tsa)
816 		utdm->si_regs->siglmr1_h &= ~(0x1 << utdm->tdm_port);
817 
818 	ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
819 
820 	free_irq(priv->ut_info->uf_info.irq, priv);
821 	netif_stop_queue(dev);
822 	netdev_reset_queue(dev);
823 	priv->hdlc_busy = 0;
824 
825 	return 0;
826 }
827 
828 static int ucc_hdlc_attach(struct net_device *dev, unsigned short encoding,
829 			   unsigned short parity)
830 {
831 	struct ucc_hdlc_private *priv = dev_to_hdlc(dev)->priv;
832 
833 	if (encoding != ENCODING_NRZ &&
834 	    encoding != ENCODING_NRZI)
835 		return -EINVAL;
836 
837 	if (parity != PARITY_NONE &&
838 	    parity != PARITY_CRC32_PR1_CCITT &&
839 	    parity != PARITY_CRC16_PR0_CCITT &&
840 	    parity != PARITY_CRC16_PR1_CCITT)
841 		return -EINVAL;
842 
843 	priv->encoding = encoding;
844 	priv->parity = parity;
845 
846 	return 0;
847 }
848 
849 #ifdef CONFIG_PM
850 static void store_clk_config(struct ucc_hdlc_private *priv)
851 {
852 	struct qe_mux *qe_mux_reg = &qe_immr->qmx;
853 
854 	/* store si clk */
855 	priv->cmxsi1cr_h = ioread32be(&qe_mux_reg->cmxsi1cr_h);
856 	priv->cmxsi1cr_l = ioread32be(&qe_mux_reg->cmxsi1cr_l);
857 
858 	/* store si sync */
859 	priv->cmxsi1syr = ioread32be(&qe_mux_reg->cmxsi1syr);
860 
861 	/* store ucc clk */
862 	memcpy_fromio(priv->cmxucr, qe_mux_reg->cmxucr, 4 * sizeof(u32));
863 }
864 
865 static void resume_clk_config(struct ucc_hdlc_private *priv)
866 {
867 	struct qe_mux *qe_mux_reg = &qe_immr->qmx;
868 
869 	memcpy_toio(qe_mux_reg->cmxucr, priv->cmxucr, 4 * sizeof(u32));
870 
871 	iowrite32be(priv->cmxsi1cr_h, &qe_mux_reg->cmxsi1cr_h);
872 	iowrite32be(priv->cmxsi1cr_l, &qe_mux_reg->cmxsi1cr_l);
873 
874 	iowrite32be(priv->cmxsi1syr, &qe_mux_reg->cmxsi1syr);
875 }
876 
877 static int uhdlc_suspend(struct device *dev)
878 {
879 	struct ucc_hdlc_private *priv = dev_get_drvdata(dev);
880 	struct ucc_tdm_info *ut_info;
881 	struct ucc_fast __iomem *uf_regs;
882 
883 	if (!priv)
884 		return -EINVAL;
885 
886 	if (!netif_running(priv->ndev))
887 		return 0;
888 
889 	netif_device_detach(priv->ndev);
890 	napi_disable(&priv->napi);
891 
892 	ut_info = priv->ut_info;
893 	uf_regs = priv->uf_regs;
894 
895 	/* backup gumr guemr*/
896 	priv->gumr = ioread32be(&uf_regs->gumr);
897 	priv->guemr = ioread8(&uf_regs->guemr);
898 
899 	priv->ucc_pram_bak = kmalloc(sizeof(*priv->ucc_pram_bak),
900 					GFP_KERNEL);
901 	if (!priv->ucc_pram_bak)
902 		return -ENOMEM;
903 
904 	/* backup HDLC parameter */
905 	memcpy_fromio(priv->ucc_pram_bak, priv->ucc_pram,
906 		      sizeof(struct ucc_hdlc_param));
907 
908 	/* store the clk configuration */
909 	store_clk_config(priv);
910 
911 	/* save power */
912 	ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
913 
914 	return 0;
915 }
916 
917 static int uhdlc_resume(struct device *dev)
918 {
919 	struct ucc_hdlc_private *priv = dev_get_drvdata(dev);
920 	struct ucc_tdm *utdm;
921 	struct ucc_tdm_info *ut_info;
922 	struct ucc_fast __iomem *uf_regs;
923 	struct ucc_fast_private *uccf;
924 	struct ucc_fast_info *uf_info;
925 	int ret, i;
926 	u32 cecr_subblock;
927 	u16 bd_status;
928 
929 	if (!priv)
930 		return -EINVAL;
931 
932 	if (!netif_running(priv->ndev))
933 		return 0;
934 
935 	utdm = priv->utdm;
936 	ut_info = priv->ut_info;
937 	uf_info = &ut_info->uf_info;
938 	uf_regs = priv->uf_regs;
939 	uccf = priv->uccf;
940 
941 	/* restore gumr guemr */
942 	iowrite8(priv->guemr, &uf_regs->guemr);
943 	iowrite32be(priv->gumr, &uf_regs->gumr);
944 
945 	/* Set Virtual Fifo registers */
946 	iowrite16be(uf_info->urfs, &uf_regs->urfs);
947 	iowrite16be(uf_info->urfet, &uf_regs->urfet);
948 	iowrite16be(uf_info->urfset, &uf_regs->urfset);
949 	iowrite16be(uf_info->utfs, &uf_regs->utfs);
950 	iowrite16be(uf_info->utfet, &uf_regs->utfet);
951 	iowrite16be(uf_info->utftt, &uf_regs->utftt);
952 	/* utfb, urfb are offsets from MURAM base */
953 	iowrite32be(uccf->ucc_fast_tx_virtual_fifo_base_offset, &uf_regs->utfb);
954 	iowrite32be(uccf->ucc_fast_rx_virtual_fifo_base_offset, &uf_regs->urfb);
955 
956 	/* Rx Tx and sync clock routing */
957 	resume_clk_config(priv);
958 
959 	iowrite32be(uf_info->uccm_mask, &uf_regs->uccm);
960 	iowrite32be(0xffffffff, &uf_regs->ucce);
961 
962 	ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
963 
964 	/* rebuild SIRAM */
965 	if (priv->tsa)
966 		ucc_tdm_init(priv->utdm, priv->ut_info);
967 
968 	/* Write to QE CECR, UCCx channel to Stop Transmission */
969 	cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
970 	ret = qe_issue_cmd(QE_STOP_TX, cecr_subblock,
971 			   (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
972 
973 	/* Set UPSMR normal mode */
974 	iowrite32be(0, &uf_regs->upsmr);
975 
976 	/* init parameter base */
977 	cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
978 	ret = qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, cecr_subblock,
979 			   QE_CR_PROTOCOL_UNSPECIFIED, priv->ucc_pram_offset);
980 
981 	priv->ucc_pram = (struct ucc_hdlc_param __iomem *)
982 				qe_muram_addr(priv->ucc_pram_offset);
983 
984 	/* restore ucc parameter */
985 	memcpy_toio(priv->ucc_pram, priv->ucc_pram_bak,
986 		    sizeof(struct ucc_hdlc_param));
987 	kfree(priv->ucc_pram_bak);
988 
989 	/* rebuild BD entry */
990 	for (i = 0; i < RX_BD_RING_LEN; i++) {
991 		if (i < (RX_BD_RING_LEN - 1))
992 			bd_status = R_E_S | R_I_S;
993 		else
994 			bd_status = R_E_S | R_I_S | R_W_S;
995 
996 		iowrite16be(bd_status, &priv->rx_bd_base[i].status);
997 		iowrite32be(priv->dma_rx_addr + i * MAX_RX_BUF_LENGTH,
998 			    &priv->rx_bd_base[i].buf);
999 	}
1000 
1001 	for (i = 0; i < TX_BD_RING_LEN; i++) {
1002 		if (i < (TX_BD_RING_LEN - 1))
1003 			bd_status =  T_I_S | T_TC_S;
1004 		else
1005 			bd_status =  T_I_S | T_TC_S | T_W_S;
1006 
1007 		iowrite16be(bd_status, &priv->tx_bd_base[i].status);
1008 		iowrite32be(priv->dma_tx_addr + i * MAX_RX_BUF_LENGTH,
1009 			    &priv->tx_bd_base[i].buf);
1010 	}
1011 
1012 	/* if hdlc is busy enable TX and RX */
1013 	if (priv->hdlc_busy == 1) {
1014 		cecr_subblock = ucc_fast_get_qe_cr_subblock(
1015 					priv->ut_info->uf_info.ucc_num);
1016 
1017 		qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
1018 			     (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
1019 
1020 		ucc_fast_enable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
1021 
1022 		/* Enable the TDM port */
1023 		if (priv->tsa)
1024 			utdm->si_regs->siglmr1_h |= (0x1 << utdm->tdm_port);
1025 	}
1026 
1027 	napi_enable(&priv->napi);
1028 	netif_device_attach(priv->ndev);
1029 
1030 	return 0;
1031 }
1032 
1033 static const struct dev_pm_ops uhdlc_pm_ops = {
1034 	.suspend = uhdlc_suspend,
1035 	.resume = uhdlc_resume,
1036 	.freeze = uhdlc_suspend,
1037 	.thaw = uhdlc_resume,
1038 };
1039 
1040 #define HDLC_PM_OPS (&uhdlc_pm_ops)
1041 
1042 #else
1043 
1044 #define HDLC_PM_OPS NULL
1045 
1046 #endif
1047 static void uhdlc_tx_timeout(struct net_device *ndev)
1048 {
1049 	netdev_err(ndev, "%s\n", __func__);
1050 }
1051 
1052 static const struct net_device_ops uhdlc_ops = {
1053 	.ndo_open       = uhdlc_open,
1054 	.ndo_stop       = uhdlc_close,
1055 	.ndo_start_xmit = hdlc_start_xmit,
1056 	.ndo_do_ioctl   = uhdlc_ioctl,
1057 	.ndo_tx_timeout	= uhdlc_tx_timeout,
1058 };
1059 
1060 static int ucc_hdlc_probe(struct platform_device *pdev)
1061 {
1062 	struct device_node *np = pdev->dev.of_node;
1063 	struct ucc_hdlc_private *uhdlc_priv = NULL;
1064 	struct ucc_tdm_info *ut_info;
1065 	struct ucc_tdm *utdm = NULL;
1066 	struct resource res;
1067 	struct net_device *dev;
1068 	hdlc_device *hdlc;
1069 	int ucc_num;
1070 	const char *sprop;
1071 	int ret;
1072 	u32 val;
1073 
1074 	ret = of_property_read_u32_index(np, "cell-index", 0, &val);
1075 	if (ret) {
1076 		dev_err(&pdev->dev, "Invalid ucc property\n");
1077 		return -ENODEV;
1078 	}
1079 
1080 	ucc_num = val - 1;
1081 	if (ucc_num > (UCC_MAX_NUM - 1) || ucc_num < 0) {
1082 		dev_err(&pdev->dev, ": Invalid UCC num\n");
1083 		return -EINVAL;
1084 	}
1085 
1086 	memcpy(&utdm_info[ucc_num], &utdm_primary_info,
1087 	       sizeof(utdm_primary_info));
1088 
1089 	ut_info = &utdm_info[ucc_num];
1090 	ut_info->uf_info.ucc_num = ucc_num;
1091 
1092 	sprop = of_get_property(np, "rx-clock-name", NULL);
1093 	if (sprop) {
1094 		ut_info->uf_info.rx_clock = qe_clock_source(sprop);
1095 		if ((ut_info->uf_info.rx_clock < QE_CLK_NONE) ||
1096 		    (ut_info->uf_info.rx_clock > QE_CLK24)) {
1097 			dev_err(&pdev->dev, "Invalid rx-clock-name property\n");
1098 			return -EINVAL;
1099 		}
1100 	} else {
1101 		dev_err(&pdev->dev, "Invalid rx-clock-name property\n");
1102 		return -EINVAL;
1103 	}
1104 
1105 	sprop = of_get_property(np, "tx-clock-name", NULL);
1106 	if (sprop) {
1107 		ut_info->uf_info.tx_clock = qe_clock_source(sprop);
1108 		if ((ut_info->uf_info.tx_clock < QE_CLK_NONE) ||
1109 		    (ut_info->uf_info.tx_clock > QE_CLK24)) {
1110 			dev_err(&pdev->dev, "Invalid tx-clock-name property\n");
1111 			return -EINVAL;
1112 		}
1113 	} else {
1114 		dev_err(&pdev->dev, "Invalid tx-clock-name property\n");
1115 		return -EINVAL;
1116 	}
1117 
1118 	ret = of_address_to_resource(np, 0, &res);
1119 	if (ret)
1120 		return -EINVAL;
1121 
1122 	ut_info->uf_info.regs = res.start;
1123 	ut_info->uf_info.irq = irq_of_parse_and_map(np, 0);
1124 
1125 	uhdlc_priv = kzalloc(sizeof(*uhdlc_priv), GFP_KERNEL);
1126 	if (!uhdlc_priv) {
1127 		return -ENOMEM;
1128 	}
1129 
1130 	dev_set_drvdata(&pdev->dev, uhdlc_priv);
1131 	uhdlc_priv->dev = &pdev->dev;
1132 	uhdlc_priv->ut_info = ut_info;
1133 
1134 	if (of_get_property(np, "fsl,tdm-interface", NULL))
1135 		uhdlc_priv->tsa = 1;
1136 
1137 	if (of_get_property(np, "fsl,ucc-internal-loopback", NULL))
1138 		uhdlc_priv->loopback = 1;
1139 
1140 	if (of_get_property(np, "fsl,hdlc-bus", NULL))
1141 		uhdlc_priv->hdlc_bus = 1;
1142 
1143 	if (uhdlc_priv->tsa == 1) {
1144 		utdm = kzalloc(sizeof(*utdm), GFP_KERNEL);
1145 		if (!utdm) {
1146 			ret = -ENOMEM;
1147 			dev_err(&pdev->dev, "No mem to alloc ucc tdm data\n");
1148 			goto free_uhdlc_priv;
1149 		}
1150 		uhdlc_priv->utdm = utdm;
1151 		ret = ucc_of_parse_tdm(np, utdm, ut_info);
1152 		if (ret)
1153 			goto free_utdm;
1154 	}
1155 
1156 	if (of_property_read_u16(np, "fsl,hmask", &uhdlc_priv->hmask))
1157 		uhdlc_priv->hmask = DEFAULT_ADDR_MASK;
1158 
1159 	ret = uhdlc_init(uhdlc_priv);
1160 	if (ret) {
1161 		dev_err(&pdev->dev, "Failed to init uhdlc\n");
1162 		goto free_utdm;
1163 	}
1164 
1165 	dev = alloc_hdlcdev(uhdlc_priv);
1166 	if (!dev) {
1167 		ret = -ENOMEM;
1168 		pr_err("ucc_hdlc: unable to allocate memory\n");
1169 		goto undo_uhdlc_init;
1170 	}
1171 
1172 	uhdlc_priv->ndev = dev;
1173 	hdlc = dev_to_hdlc(dev);
1174 	dev->tx_queue_len = 16;
1175 	dev->netdev_ops = &uhdlc_ops;
1176 	dev->watchdog_timeo = 2 * HZ;
1177 	hdlc->attach = ucc_hdlc_attach;
1178 	hdlc->xmit = ucc_hdlc_tx;
1179 	netif_napi_add(dev, &uhdlc_priv->napi, ucc_hdlc_poll, 32);
1180 	if (register_hdlc_device(dev)) {
1181 		ret = -ENOBUFS;
1182 		pr_err("ucc_hdlc: unable to register hdlc device\n");
1183 		goto free_dev;
1184 	}
1185 
1186 	return 0;
1187 
1188 free_dev:
1189 	free_netdev(dev);
1190 undo_uhdlc_init:
1191 free_utdm:
1192 	if (uhdlc_priv->tsa)
1193 		kfree(utdm);
1194 free_uhdlc_priv:
1195 	kfree(uhdlc_priv);
1196 	return ret;
1197 }
1198 
1199 static int ucc_hdlc_remove(struct platform_device *pdev)
1200 {
1201 	struct ucc_hdlc_private *priv = dev_get_drvdata(&pdev->dev);
1202 
1203 	uhdlc_memclean(priv);
1204 
1205 	if (priv->utdm->si_regs) {
1206 		iounmap(priv->utdm->si_regs);
1207 		priv->utdm->si_regs = NULL;
1208 	}
1209 
1210 	if (priv->utdm->siram) {
1211 		iounmap(priv->utdm->siram);
1212 		priv->utdm->siram = NULL;
1213 	}
1214 	kfree(priv);
1215 
1216 	dev_info(&pdev->dev, "UCC based hdlc module removed\n");
1217 
1218 	return 0;
1219 }
1220 
1221 static const struct of_device_id fsl_ucc_hdlc_of_match[] = {
1222 	{
1223 	.compatible = "fsl,ucc-hdlc",
1224 	},
1225 	{},
1226 };
1227 
1228 MODULE_DEVICE_TABLE(of, fsl_ucc_hdlc_of_match);
1229 
1230 static struct platform_driver ucc_hdlc_driver = {
1231 	.probe	= ucc_hdlc_probe,
1232 	.remove	= ucc_hdlc_remove,
1233 	.driver	= {
1234 		.name		= DRV_NAME,
1235 		.pm		= HDLC_PM_OPS,
1236 		.of_match_table	= fsl_ucc_hdlc_of_match,
1237 	},
1238 };
1239 
1240 module_platform_driver(ucc_hdlc_driver);
1241 MODULE_LICENSE("GPL");
1242