xref: /openbmc/linux/drivers/usb/musb/tusb6010_omap.c (revision a36954f5)
1 /*
2  * TUSB6010 USB 2.0 OTG Dual Role controller OMAP DMA interface
3  *
4  * Copyright (C) 2006 Nokia Corporation
5  * Tony Lindgren <tony@atomide.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/module.h>
12 #include <linux/kernel.h>
13 #include <linux/errno.h>
14 #include <linux/usb.h>
15 #include <linux/platform_device.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/slab.h>
18 #include <linux/omap-dma.h>
19 
20 #include "musb_core.h"
21 #include "tusb6010.h"
22 
23 #define to_chdat(c)		((struct tusb_omap_dma_ch *)(c)->private_data)
24 
25 #define MAX_DMAREQ		5	/* REVISIT: Really 6, but req5 not OK */
26 
27 #define OMAP24XX_DMA_EXT_DMAREQ0	2
28 #define OMAP24XX_DMA_EXT_DMAREQ1	3
29 #define OMAP242X_DMA_EXT_DMAREQ2	14
30 #define OMAP242X_DMA_EXT_DMAREQ3	15
31 #define OMAP242X_DMA_EXT_DMAREQ4	16
32 #define OMAP242X_DMA_EXT_DMAREQ5	64
33 
34 struct tusb_omap_dma_ch {
35 	struct musb		*musb;
36 	void __iomem		*tbase;
37 	unsigned long		phys_offset;
38 	int			epnum;
39 	u8			tx;
40 	struct musb_hw_ep	*hw_ep;
41 
42 	int			ch;
43 	s8			dmareq;
44 	s8			sync_dev;
45 
46 	struct tusb_omap_dma	*tusb_dma;
47 
48 	dma_addr_t		dma_addr;
49 
50 	u32			len;
51 	u16			packet_sz;
52 	u16			transfer_packet_sz;
53 	u32			transfer_len;
54 	u32			completed_len;
55 };
56 
57 struct tusb_omap_dma {
58 	struct dma_controller		controller;
59 	void __iomem			*tbase;
60 
61 	int				ch;
62 	s8				dmareq;
63 	s8				sync_dev;
64 	unsigned			multichannel:1;
65 };
66 
67 /*
68  * Allocate dmareq0 to the current channel unless it's already taken
69  */
70 static inline int tusb_omap_use_shared_dmareq(struct tusb_omap_dma_ch *chdat)
71 {
72 	u32		reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
73 
74 	if (reg != 0) {
75 		dev_dbg(chdat->musb->controller, "ep%i dmareq0 is busy for ep%i\n",
76 			chdat->epnum, reg & 0xf);
77 		return -EAGAIN;
78 	}
79 
80 	if (chdat->tx)
81 		reg = (1 << 4) | chdat->epnum;
82 	else
83 		reg = chdat->epnum;
84 
85 	musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, reg);
86 
87 	return 0;
88 }
89 
90 static inline void tusb_omap_free_shared_dmareq(struct tusb_omap_dma_ch *chdat)
91 {
92 	u32		reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
93 
94 	if ((reg & 0xf) != chdat->epnum) {
95 		printk(KERN_ERR "ep%i trying to release dmareq0 for ep%i\n",
96 			chdat->epnum, reg & 0xf);
97 		return;
98 	}
99 	musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, 0);
100 }
101 
102 /*
103  * See also musb_dma_completion in plat_uds.c and musb_g_[tx|rx]() in
104  * musb_gadget.c.
105  */
106 static void tusb_omap_dma_cb(int lch, u16 ch_status, void *data)
107 {
108 	struct dma_channel	*channel = (struct dma_channel *)data;
109 	struct tusb_omap_dma_ch	*chdat = to_chdat(channel);
110 	struct tusb_omap_dma	*tusb_dma = chdat->tusb_dma;
111 	struct musb		*musb = chdat->musb;
112 	struct device		*dev = musb->controller;
113 	struct musb_hw_ep	*hw_ep = chdat->hw_ep;
114 	void __iomem		*ep_conf = hw_ep->conf;
115 	void __iomem		*mbase = musb->mregs;
116 	unsigned long		remaining, flags, pio;
117 	int			ch;
118 
119 	spin_lock_irqsave(&musb->lock, flags);
120 
121 	if (tusb_dma->multichannel)
122 		ch = chdat->ch;
123 	else
124 		ch = tusb_dma->ch;
125 
126 	if (ch_status != OMAP_DMA_BLOCK_IRQ)
127 		printk(KERN_ERR "TUSB DMA error status: %i\n", ch_status);
128 
129 	dev_dbg(musb->controller, "ep%i %s dma callback ch: %i status: %x\n",
130 		chdat->epnum, chdat->tx ? "tx" : "rx",
131 		ch, ch_status);
132 
133 	if (chdat->tx)
134 		remaining = musb_readl(ep_conf, TUSB_EP_TX_OFFSET);
135 	else
136 		remaining = musb_readl(ep_conf, TUSB_EP_RX_OFFSET);
137 
138 	remaining = TUSB_EP_CONFIG_XFR_SIZE(remaining);
139 
140 	/* HW issue #10: XFR_SIZE may get corrupt on DMA (both async & sync) */
141 	if (unlikely(remaining > chdat->transfer_len)) {
142 		dev_dbg(musb->controller, "Corrupt %s dma ch%i XFR_SIZE: 0x%08lx\n",
143 			chdat->tx ? "tx" : "rx", chdat->ch,
144 			remaining);
145 		remaining = 0;
146 	}
147 
148 	channel->actual_len = chdat->transfer_len - remaining;
149 	pio = chdat->len - channel->actual_len;
150 
151 	dev_dbg(musb->controller, "DMA remaining %lu/%u\n", remaining, chdat->transfer_len);
152 
153 	/* Transfer remaining 1 - 31 bytes */
154 	if (pio > 0 && pio < 32) {
155 		u8	*buf;
156 
157 		dev_dbg(musb->controller, "Using PIO for remaining %lu bytes\n", pio);
158 		buf = phys_to_virt((u32)chdat->dma_addr) + chdat->transfer_len;
159 		if (chdat->tx) {
160 			dma_unmap_single(dev, chdat->dma_addr,
161 						chdat->transfer_len,
162 						DMA_TO_DEVICE);
163 			musb_write_fifo(hw_ep, pio, buf);
164 		} else {
165 			dma_unmap_single(dev, chdat->dma_addr,
166 						chdat->transfer_len,
167 						DMA_FROM_DEVICE);
168 			musb_read_fifo(hw_ep, pio, buf);
169 		}
170 		channel->actual_len += pio;
171 	}
172 
173 	if (!tusb_dma->multichannel)
174 		tusb_omap_free_shared_dmareq(chdat);
175 
176 	channel->status = MUSB_DMA_STATUS_FREE;
177 
178 	/* Handle only RX callbacks here. TX callbacks must be handled based
179 	 * on the TUSB DMA status interrupt.
180 	 * REVISIT: Use both TUSB DMA status interrupt and OMAP DMA callback
181 	 * interrupt for RX and TX.
182 	 */
183 	if (!chdat->tx)
184 		musb_dma_completion(musb, chdat->epnum, chdat->tx);
185 
186 	/* We must terminate short tx transfers manually by setting TXPKTRDY.
187 	 * REVISIT: This same problem may occur with other MUSB dma as well.
188 	 * Easy to test with g_ether by pinging the MUSB board with ping -s54.
189 	 */
190 	if ((chdat->transfer_len < chdat->packet_sz)
191 			|| (chdat->transfer_len % chdat->packet_sz != 0)) {
192 		u16	csr;
193 
194 		if (chdat->tx) {
195 			dev_dbg(musb->controller, "terminating short tx packet\n");
196 			musb_ep_select(mbase, chdat->epnum);
197 			csr = musb_readw(hw_ep->regs, MUSB_TXCSR);
198 			csr |= MUSB_TXCSR_MODE | MUSB_TXCSR_TXPKTRDY
199 				| MUSB_TXCSR_P_WZC_BITS;
200 			musb_writew(hw_ep->regs, MUSB_TXCSR, csr);
201 		}
202 	}
203 
204 	spin_unlock_irqrestore(&musb->lock, flags);
205 }
206 
207 static int tusb_omap_dma_program(struct dma_channel *channel, u16 packet_sz,
208 				u8 rndis_mode, dma_addr_t dma_addr, u32 len)
209 {
210 	struct tusb_omap_dma_ch		*chdat = to_chdat(channel);
211 	struct tusb_omap_dma		*tusb_dma = chdat->tusb_dma;
212 	struct musb			*musb = chdat->musb;
213 	struct device			*dev = musb->controller;
214 	struct musb_hw_ep		*hw_ep = chdat->hw_ep;
215 	void __iomem			*mbase = musb->mregs;
216 	void __iomem			*ep_conf = hw_ep->conf;
217 	dma_addr_t			fifo = hw_ep->fifo_sync;
218 	struct omap_dma_channel_params	dma_params;
219 	u32				dma_remaining;
220 	int				src_burst, dst_burst;
221 	u16				csr;
222 	u32				psize;
223 	int				ch;
224 	s8				dmareq;
225 	s8				sync_dev;
226 
227 	if (unlikely(dma_addr & 0x1) || (len < 32) || (len > packet_sz))
228 		return false;
229 
230 	/*
231 	 * HW issue #10: Async dma will eventually corrupt the XFR_SIZE
232 	 * register which will cause missed DMA interrupt. We could try to
233 	 * use a timer for the callback, but it is unsafe as the XFR_SIZE
234 	 * register is corrupt, and we won't know if the DMA worked.
235 	 */
236 	if (dma_addr & 0x2)
237 		return false;
238 
239 	/*
240 	 * Because of HW issue #10, it seems like mixing sync DMA and async
241 	 * PIO access can confuse the DMA. Make sure XFR_SIZE is reset before
242 	 * using the channel for DMA.
243 	 */
244 	if (chdat->tx)
245 		dma_remaining = musb_readl(ep_conf, TUSB_EP_TX_OFFSET);
246 	else
247 		dma_remaining = musb_readl(ep_conf, TUSB_EP_RX_OFFSET);
248 
249 	dma_remaining = TUSB_EP_CONFIG_XFR_SIZE(dma_remaining);
250 	if (dma_remaining) {
251 		dev_dbg(musb->controller, "Busy %s dma ch%i, not using: %08x\n",
252 			chdat->tx ? "tx" : "rx", chdat->ch,
253 			dma_remaining);
254 		return false;
255 	}
256 
257 	chdat->transfer_len = len & ~0x1f;
258 
259 	if (len < packet_sz)
260 		chdat->transfer_packet_sz = chdat->transfer_len;
261 	else
262 		chdat->transfer_packet_sz = packet_sz;
263 
264 	if (tusb_dma->multichannel) {
265 		ch = chdat->ch;
266 		dmareq = chdat->dmareq;
267 		sync_dev = chdat->sync_dev;
268 	} else {
269 		if (tusb_omap_use_shared_dmareq(chdat) != 0) {
270 			dev_dbg(musb->controller, "could not get dma for ep%i\n", chdat->epnum);
271 			return false;
272 		}
273 		if (tusb_dma->ch < 0) {
274 			/* REVISIT: This should get blocked earlier, happens
275 			 * with MSC ErrorRecoveryTest
276 			 */
277 			WARN_ON(1);
278 			return false;
279 		}
280 
281 		ch = tusb_dma->ch;
282 		dmareq = tusb_dma->dmareq;
283 		sync_dev = tusb_dma->sync_dev;
284 		omap_set_dma_callback(ch, tusb_omap_dma_cb, channel);
285 	}
286 
287 	chdat->packet_sz = packet_sz;
288 	chdat->len = len;
289 	channel->actual_len = 0;
290 	chdat->dma_addr = dma_addr;
291 	channel->status = MUSB_DMA_STATUS_BUSY;
292 
293 	/* Since we're recycling dma areas, we need to clean or invalidate */
294 	if (chdat->tx)
295 		dma_map_single(dev, phys_to_virt(dma_addr), len,
296 				DMA_TO_DEVICE);
297 	else
298 		dma_map_single(dev, phys_to_virt(dma_addr), len,
299 				DMA_FROM_DEVICE);
300 
301 	/* Use 16-bit transfer if dma_addr is not 32-bit aligned */
302 	if ((dma_addr & 0x3) == 0) {
303 		dma_params.data_type = OMAP_DMA_DATA_TYPE_S32;
304 		dma_params.elem_count = 8;		/* Elements in frame */
305 	} else {
306 		dma_params.data_type = OMAP_DMA_DATA_TYPE_S16;
307 		dma_params.elem_count = 16;		/* Elements in frame */
308 		fifo = hw_ep->fifo_async;
309 	}
310 
311 	dma_params.frame_count	= chdat->transfer_len / 32; /* Burst sz frame */
312 
313 	dev_dbg(musb->controller, "ep%i %s dma ch%i dma: %pad len: %u(%u) packet_sz: %i(%i)\n",
314 		chdat->epnum, chdat->tx ? "tx" : "rx",
315 		ch, &dma_addr, chdat->transfer_len, len,
316 		chdat->transfer_packet_sz, packet_sz);
317 
318 	/*
319 	 * Prepare omap DMA for transfer
320 	 */
321 	if (chdat->tx) {
322 		dma_params.src_amode	= OMAP_DMA_AMODE_POST_INC;
323 		dma_params.src_start	= (unsigned long)dma_addr;
324 		dma_params.src_ei	= 0;
325 		dma_params.src_fi	= 0;
326 
327 		dma_params.dst_amode	= OMAP_DMA_AMODE_DOUBLE_IDX;
328 		dma_params.dst_start	= (unsigned long)fifo;
329 		dma_params.dst_ei	= 1;
330 		dma_params.dst_fi	= -31;	/* Loop 32 byte window */
331 
332 		dma_params.trigger	= sync_dev;
333 		dma_params.sync_mode	= OMAP_DMA_SYNC_FRAME;
334 		dma_params.src_or_dst_synch	= 0;	/* Dest sync */
335 
336 		src_burst = OMAP_DMA_DATA_BURST_16;	/* 16x32 read */
337 		dst_burst = OMAP_DMA_DATA_BURST_8;	/* 8x32 write */
338 	} else {
339 		dma_params.src_amode	= OMAP_DMA_AMODE_DOUBLE_IDX;
340 		dma_params.src_start	= (unsigned long)fifo;
341 		dma_params.src_ei	= 1;
342 		dma_params.src_fi	= -31;	/* Loop 32 byte window */
343 
344 		dma_params.dst_amode	= OMAP_DMA_AMODE_POST_INC;
345 		dma_params.dst_start	= (unsigned long)dma_addr;
346 		dma_params.dst_ei	= 0;
347 		dma_params.dst_fi	= 0;
348 
349 		dma_params.trigger	= sync_dev;
350 		dma_params.sync_mode	= OMAP_DMA_SYNC_FRAME;
351 		dma_params.src_or_dst_synch	= 1;	/* Source sync */
352 
353 		src_burst = OMAP_DMA_DATA_BURST_8;	/* 8x32 read */
354 		dst_burst = OMAP_DMA_DATA_BURST_16;	/* 16x32 write */
355 	}
356 
357 	dev_dbg(musb->controller, "ep%i %s using %i-bit %s dma from 0x%08lx to 0x%08lx\n",
358 		chdat->epnum, chdat->tx ? "tx" : "rx",
359 		(dma_params.data_type == OMAP_DMA_DATA_TYPE_S32) ? 32 : 16,
360 		((dma_addr & 0x3) == 0) ? "sync" : "async",
361 		dma_params.src_start, dma_params.dst_start);
362 
363 	omap_set_dma_params(ch, &dma_params);
364 	omap_set_dma_src_burst_mode(ch, src_burst);
365 	omap_set_dma_dest_burst_mode(ch, dst_burst);
366 	omap_set_dma_write_mode(ch, OMAP_DMA_WRITE_LAST_NON_POSTED);
367 
368 	/*
369 	 * Prepare MUSB for DMA transfer
370 	 */
371 	if (chdat->tx) {
372 		musb_ep_select(mbase, chdat->epnum);
373 		csr = musb_readw(hw_ep->regs, MUSB_TXCSR);
374 		csr |= (MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB
375 			| MUSB_TXCSR_DMAMODE | MUSB_TXCSR_MODE);
376 		csr &= ~MUSB_TXCSR_P_UNDERRUN;
377 		musb_writew(hw_ep->regs, MUSB_TXCSR, csr);
378 	} else {
379 		musb_ep_select(mbase, chdat->epnum);
380 		csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
381 		csr |= MUSB_RXCSR_DMAENAB;
382 		csr &= ~(MUSB_RXCSR_AUTOCLEAR | MUSB_RXCSR_DMAMODE);
383 		musb_writew(hw_ep->regs, MUSB_RXCSR,
384 			csr | MUSB_RXCSR_P_WZC_BITS);
385 	}
386 
387 	/*
388 	 * Start DMA transfer
389 	 */
390 	omap_start_dma(ch);
391 
392 	if (chdat->tx) {
393 		/* Send transfer_packet_sz packets at a time */
394 		psize = musb_readl(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET);
395 		psize &= ~0x7ff;
396 		psize |= chdat->transfer_packet_sz;
397 		musb_writel(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET, psize);
398 
399 		musb_writel(ep_conf, TUSB_EP_TX_OFFSET,
400 			TUSB_EP_CONFIG_XFR_SIZE(chdat->transfer_len));
401 	} else {
402 		/* Receive transfer_packet_sz packets at a time */
403 		psize = musb_readl(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET);
404 		psize &= ~(0x7ff << 16);
405 		psize |= (chdat->transfer_packet_sz << 16);
406 		musb_writel(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET, psize);
407 
408 		musb_writel(ep_conf, TUSB_EP_RX_OFFSET,
409 			TUSB_EP_CONFIG_XFR_SIZE(chdat->transfer_len));
410 	}
411 
412 	return true;
413 }
414 
415 static int tusb_omap_dma_abort(struct dma_channel *channel)
416 {
417 	struct tusb_omap_dma_ch	*chdat = to_chdat(channel);
418 	struct tusb_omap_dma	*tusb_dma = chdat->tusb_dma;
419 
420 	if (!tusb_dma->multichannel) {
421 		if (tusb_dma->ch >= 0) {
422 			omap_stop_dma(tusb_dma->ch);
423 			omap_free_dma(tusb_dma->ch);
424 			tusb_dma->ch = -1;
425 		}
426 
427 		tusb_dma->dmareq = -1;
428 		tusb_dma->sync_dev = -1;
429 	}
430 
431 	channel->status = MUSB_DMA_STATUS_FREE;
432 
433 	return 0;
434 }
435 
436 static inline int tusb_omap_dma_allocate_dmareq(struct tusb_omap_dma_ch *chdat)
437 {
438 	u32		reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
439 	int		i, dmareq_nr = -1;
440 
441 	const int sync_dev[6] = {
442 		OMAP24XX_DMA_EXT_DMAREQ0,
443 		OMAP24XX_DMA_EXT_DMAREQ1,
444 		OMAP242X_DMA_EXT_DMAREQ2,
445 		OMAP242X_DMA_EXT_DMAREQ3,
446 		OMAP242X_DMA_EXT_DMAREQ4,
447 		OMAP242X_DMA_EXT_DMAREQ5,
448 	};
449 
450 	for (i = 0; i < MAX_DMAREQ; i++) {
451 		int cur = (reg & (0xf << (i * 5))) >> (i * 5);
452 		if (cur == 0) {
453 			dmareq_nr = i;
454 			break;
455 		}
456 	}
457 
458 	if (dmareq_nr == -1)
459 		return -EAGAIN;
460 
461 	reg |= (chdat->epnum << (dmareq_nr * 5));
462 	if (chdat->tx)
463 		reg |= ((1 << 4) << (dmareq_nr * 5));
464 	musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, reg);
465 
466 	chdat->dmareq = dmareq_nr;
467 	chdat->sync_dev = sync_dev[chdat->dmareq];
468 
469 	return 0;
470 }
471 
472 static inline void tusb_omap_dma_free_dmareq(struct tusb_omap_dma_ch *chdat)
473 {
474 	u32 reg;
475 
476 	if (!chdat || chdat->dmareq < 0)
477 		return;
478 
479 	reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
480 	reg &= ~(0x1f << (chdat->dmareq * 5));
481 	musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, reg);
482 
483 	chdat->dmareq = -1;
484 	chdat->sync_dev = -1;
485 }
486 
487 static struct dma_channel *dma_channel_pool[MAX_DMAREQ];
488 
489 static struct dma_channel *
490 tusb_omap_dma_allocate(struct dma_controller *c,
491 		struct musb_hw_ep *hw_ep,
492 		u8 tx)
493 {
494 	int ret, i;
495 	const char		*dev_name;
496 	struct tusb_omap_dma	*tusb_dma;
497 	struct musb		*musb;
498 	void __iomem		*tbase;
499 	struct dma_channel	*channel = NULL;
500 	struct tusb_omap_dma_ch	*chdat = NULL;
501 	u32			reg;
502 
503 	tusb_dma = container_of(c, struct tusb_omap_dma, controller);
504 	musb = tusb_dma->controller.musb;
505 	tbase = musb->ctrl_base;
506 
507 	reg = musb_readl(tbase, TUSB_DMA_INT_MASK);
508 	if (tx)
509 		reg &= ~(1 << hw_ep->epnum);
510 	else
511 		reg &= ~(1 << (hw_ep->epnum + 15));
512 	musb_writel(tbase, TUSB_DMA_INT_MASK, reg);
513 
514 	/* REVISIT: Why does dmareq5 not work? */
515 	if (hw_ep->epnum == 0) {
516 		dev_dbg(musb->controller, "Not allowing DMA for ep0 %s\n", tx ? "tx" : "rx");
517 		return NULL;
518 	}
519 
520 	for (i = 0; i < MAX_DMAREQ; i++) {
521 		struct dma_channel *ch = dma_channel_pool[i];
522 		if (ch->status == MUSB_DMA_STATUS_UNKNOWN) {
523 			ch->status = MUSB_DMA_STATUS_FREE;
524 			channel = ch;
525 			chdat = ch->private_data;
526 			break;
527 		}
528 	}
529 
530 	if (!channel)
531 		return NULL;
532 
533 	if (tx) {
534 		chdat->tx = 1;
535 		dev_name = "TUSB transmit";
536 	} else {
537 		chdat->tx = 0;
538 		dev_name = "TUSB receive";
539 	}
540 
541 	chdat->musb = tusb_dma->controller.musb;
542 	chdat->tbase = tusb_dma->tbase;
543 	chdat->hw_ep = hw_ep;
544 	chdat->epnum = hw_ep->epnum;
545 	chdat->dmareq = -1;
546 	chdat->completed_len = 0;
547 	chdat->tusb_dma = tusb_dma;
548 
549 	channel->max_len = 0x7fffffff;
550 	channel->desired_mode = 0;
551 	channel->actual_len = 0;
552 
553 	if (tusb_dma->multichannel) {
554 		ret = tusb_omap_dma_allocate_dmareq(chdat);
555 		if (ret != 0)
556 			goto free_dmareq;
557 
558 		ret = omap_request_dma(chdat->sync_dev, dev_name,
559 				tusb_omap_dma_cb, channel, &chdat->ch);
560 		if (ret != 0)
561 			goto free_dmareq;
562 	} else if (tusb_dma->ch == -1) {
563 		tusb_dma->dmareq = 0;
564 		tusb_dma->sync_dev = OMAP24XX_DMA_EXT_DMAREQ0;
565 
566 		/* Callback data gets set later in the shared dmareq case */
567 		ret = omap_request_dma(tusb_dma->sync_dev, "TUSB shared",
568 				tusb_omap_dma_cb, NULL, &tusb_dma->ch);
569 		if (ret != 0)
570 			goto free_dmareq;
571 
572 		chdat->dmareq = -1;
573 		chdat->ch = -1;
574 	}
575 
576 	dev_dbg(musb->controller, "ep%i %s dma: %s dma%i dmareq%i sync%i\n",
577 		chdat->epnum,
578 		chdat->tx ? "tx" : "rx",
579 		chdat->ch >= 0 ? "dedicated" : "shared",
580 		chdat->ch >= 0 ? chdat->ch : tusb_dma->ch,
581 		chdat->dmareq >= 0 ? chdat->dmareq : tusb_dma->dmareq,
582 		chdat->sync_dev >= 0 ? chdat->sync_dev : tusb_dma->sync_dev);
583 
584 	return channel;
585 
586 free_dmareq:
587 	tusb_omap_dma_free_dmareq(chdat);
588 
589 	dev_dbg(musb->controller, "ep%i: Could not get a DMA channel\n", chdat->epnum);
590 	channel->status = MUSB_DMA_STATUS_UNKNOWN;
591 
592 	return NULL;
593 }
594 
595 static void tusb_omap_dma_release(struct dma_channel *channel)
596 {
597 	struct tusb_omap_dma_ch	*chdat = to_chdat(channel);
598 	struct musb		*musb = chdat->musb;
599 	void __iomem		*tbase = musb->ctrl_base;
600 	u32			reg;
601 
602 	dev_dbg(musb->controller, "ep%i ch%i\n", chdat->epnum, chdat->ch);
603 
604 	reg = musb_readl(tbase, TUSB_DMA_INT_MASK);
605 	if (chdat->tx)
606 		reg |= (1 << chdat->epnum);
607 	else
608 		reg |= (1 << (chdat->epnum + 15));
609 	musb_writel(tbase, TUSB_DMA_INT_MASK, reg);
610 
611 	reg = musb_readl(tbase, TUSB_DMA_INT_CLEAR);
612 	if (chdat->tx)
613 		reg |= (1 << chdat->epnum);
614 	else
615 		reg |= (1 << (chdat->epnum + 15));
616 	musb_writel(tbase, TUSB_DMA_INT_CLEAR, reg);
617 
618 	channel->status = MUSB_DMA_STATUS_UNKNOWN;
619 
620 	if (chdat->ch >= 0) {
621 		omap_stop_dma(chdat->ch);
622 		omap_free_dma(chdat->ch);
623 		chdat->ch = -1;
624 	}
625 
626 	if (chdat->dmareq >= 0)
627 		tusb_omap_dma_free_dmareq(chdat);
628 
629 	channel = NULL;
630 }
631 
632 void tusb_dma_controller_destroy(struct dma_controller *c)
633 {
634 	struct tusb_omap_dma	*tusb_dma;
635 	int			i;
636 
637 	tusb_dma = container_of(c, struct tusb_omap_dma, controller);
638 	for (i = 0; i < MAX_DMAREQ; i++) {
639 		struct dma_channel *ch = dma_channel_pool[i];
640 		if (ch) {
641 			kfree(ch->private_data);
642 			kfree(ch);
643 		}
644 	}
645 
646 	if (tusb_dma && !tusb_dma->multichannel && tusb_dma->ch >= 0)
647 		omap_free_dma(tusb_dma->ch);
648 
649 	kfree(tusb_dma);
650 }
651 EXPORT_SYMBOL_GPL(tusb_dma_controller_destroy);
652 
653 struct dma_controller *
654 tusb_dma_controller_create(struct musb *musb, void __iomem *base)
655 {
656 	void __iomem		*tbase = musb->ctrl_base;
657 	struct tusb_omap_dma	*tusb_dma;
658 	int			i;
659 
660 	/* REVISIT: Get dmareq lines used from board-*.c */
661 
662 	musb_writel(musb->ctrl_base, TUSB_DMA_INT_MASK, 0x7fffffff);
663 	musb_writel(musb->ctrl_base, TUSB_DMA_EP_MAP, 0);
664 
665 	musb_writel(tbase, TUSB_DMA_REQ_CONF,
666 		TUSB_DMA_REQ_CONF_BURST_SIZE(2)
667 		| TUSB_DMA_REQ_CONF_DMA_REQ_EN(0x3f)
668 		| TUSB_DMA_REQ_CONF_DMA_REQ_ASSER(2));
669 
670 	tusb_dma = kzalloc(sizeof(struct tusb_omap_dma), GFP_KERNEL);
671 	if (!tusb_dma)
672 		goto out;
673 
674 	tusb_dma->controller.musb = musb;
675 	tusb_dma->tbase = musb->ctrl_base;
676 
677 	tusb_dma->ch = -1;
678 	tusb_dma->dmareq = -1;
679 	tusb_dma->sync_dev = -1;
680 
681 	tusb_dma->controller.channel_alloc = tusb_omap_dma_allocate;
682 	tusb_dma->controller.channel_release = tusb_omap_dma_release;
683 	tusb_dma->controller.channel_program = tusb_omap_dma_program;
684 	tusb_dma->controller.channel_abort = tusb_omap_dma_abort;
685 
686 	if (musb->tusb_revision >= TUSB_REV_30)
687 		tusb_dma->multichannel = 1;
688 
689 	for (i = 0; i < MAX_DMAREQ; i++) {
690 		struct dma_channel	*ch;
691 		struct tusb_omap_dma_ch	*chdat;
692 
693 		ch = kzalloc(sizeof(struct dma_channel), GFP_KERNEL);
694 		if (!ch)
695 			goto cleanup;
696 
697 		dma_channel_pool[i] = ch;
698 
699 		chdat = kzalloc(sizeof(struct tusb_omap_dma_ch), GFP_KERNEL);
700 		if (!chdat)
701 			goto cleanup;
702 
703 		ch->status = MUSB_DMA_STATUS_UNKNOWN;
704 		ch->private_data = chdat;
705 	}
706 
707 	return &tusb_dma->controller;
708 
709 cleanup:
710 	musb_dma_controller_destroy(&tusb_dma->controller);
711 out:
712 	return NULL;
713 }
714 EXPORT_SYMBOL_GPL(tusb_dma_controller_create);
715