xref: /openbmc/linux/drivers/usb/musb/tusb6010_omap.c (revision fd589a8f)
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/init.h>
15 #include <linux/usb.h>
16 #include <linux/platform_device.h>
17 #include <linux/dma-mapping.h>
18 #include <mach/dma.h>
19 #include <mach/mux.h>
20 
21 #include "musb_core.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 struct tusb_omap_dma_ch {
28 	struct musb		*musb;
29 	void __iomem		*tbase;
30 	unsigned long		phys_offset;
31 	int			epnum;
32 	u8			tx;
33 	struct musb_hw_ep	*hw_ep;
34 
35 	int			ch;
36 	s8			dmareq;
37 	s8			sync_dev;
38 
39 	struct tusb_omap_dma	*tusb_dma;
40 
41 	void __iomem		*dma_addr;
42 
43 	u32			len;
44 	u16			packet_sz;
45 	u16			transfer_packet_sz;
46 	u32			transfer_len;
47 	u32			completed_len;
48 };
49 
50 struct tusb_omap_dma {
51 	struct dma_controller		controller;
52 	struct musb			*musb;
53 	void __iomem			*tbase;
54 
55 	int				ch;
56 	s8				dmareq;
57 	s8				sync_dev;
58 	unsigned			multichannel:1;
59 };
60 
61 static int tusb_omap_dma_start(struct dma_controller *c)
62 {
63 	struct tusb_omap_dma	*tusb_dma;
64 
65 	tusb_dma = container_of(c, struct tusb_omap_dma, controller);
66 
67 	/* DBG(3, "ep%i ch: %i\n", chdat->epnum, chdat->ch); */
68 
69 	return 0;
70 }
71 
72 static int tusb_omap_dma_stop(struct dma_controller *c)
73 {
74 	struct tusb_omap_dma	*tusb_dma;
75 
76 	tusb_dma = container_of(c, struct tusb_omap_dma, controller);
77 
78 	/* DBG(3, "ep%i ch: %i\n", chdat->epnum, chdat->ch); */
79 
80 	return 0;
81 }
82 
83 /*
84  * Allocate dmareq0 to the current channel unless it's already taken
85  */
86 static inline int tusb_omap_use_shared_dmareq(struct tusb_omap_dma_ch *chdat)
87 {
88 	u32		reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
89 
90 	if (reg != 0) {
91 		DBG(3, "ep%i dmareq0 is busy for ep%i\n",
92 			chdat->epnum, reg & 0xf);
93 		return -EAGAIN;
94 	}
95 
96 	if (chdat->tx)
97 		reg = (1 << 4) | chdat->epnum;
98 	else
99 		reg = chdat->epnum;
100 
101 	musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, reg);
102 
103 	return 0;
104 }
105 
106 static inline void tusb_omap_free_shared_dmareq(struct tusb_omap_dma_ch *chdat)
107 {
108 	u32		reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
109 
110 	if ((reg & 0xf) != chdat->epnum) {
111 		printk(KERN_ERR "ep%i trying to release dmareq0 for ep%i\n",
112 			chdat->epnum, reg & 0xf);
113 		return;
114 	}
115 	musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, 0);
116 }
117 
118 /*
119  * See also musb_dma_completion in plat_uds.c and musb_g_[tx|rx]() in
120  * musb_gadget.c.
121  */
122 static void tusb_omap_dma_cb(int lch, u16 ch_status, void *data)
123 {
124 	struct dma_channel	*channel = (struct dma_channel *)data;
125 	struct tusb_omap_dma_ch	*chdat = to_chdat(channel);
126 	struct tusb_omap_dma	*tusb_dma = chdat->tusb_dma;
127 	struct musb		*musb = chdat->musb;
128 	struct musb_hw_ep	*hw_ep = chdat->hw_ep;
129 	void __iomem		*ep_conf = hw_ep->conf;
130 	void __iomem		*mbase = musb->mregs;
131 	unsigned long		remaining, flags, pio;
132 	int			ch;
133 
134 	spin_lock_irqsave(&musb->lock, flags);
135 
136 	if (tusb_dma->multichannel)
137 		ch = chdat->ch;
138 	else
139 		ch = tusb_dma->ch;
140 
141 	if (ch_status != OMAP_DMA_BLOCK_IRQ)
142 		printk(KERN_ERR "TUSB DMA error status: %i\n", ch_status);
143 
144 	DBG(3, "ep%i %s dma callback ch: %i status: %x\n",
145 		chdat->epnum, chdat->tx ? "tx" : "rx",
146 		ch, ch_status);
147 
148 	if (chdat->tx)
149 		remaining = musb_readl(ep_conf, TUSB_EP_TX_OFFSET);
150 	else
151 		remaining = musb_readl(ep_conf, TUSB_EP_RX_OFFSET);
152 
153 	remaining = TUSB_EP_CONFIG_XFR_SIZE(remaining);
154 
155 	/* HW issue #10: XFR_SIZE may get corrupt on DMA (both async & sync) */
156 	if (unlikely(remaining > chdat->transfer_len)) {
157 		DBG(2, "Corrupt %s dma ch%i XFR_SIZE: 0x%08lx\n",
158 			chdat->tx ? "tx" : "rx", chdat->ch,
159 			remaining);
160 		remaining = 0;
161 	}
162 
163 	channel->actual_len = chdat->transfer_len - remaining;
164 	pio = chdat->len - channel->actual_len;
165 
166 	DBG(3, "DMA remaining %lu/%u\n", remaining, chdat->transfer_len);
167 
168 	/* Transfer remaining 1 - 31 bytes */
169 	if (pio > 0 && pio < 32) {
170 		u8	*buf;
171 
172 		DBG(3, "Using PIO for remaining %lu bytes\n", pio);
173 		buf = phys_to_virt((u32)chdat->dma_addr) + chdat->transfer_len;
174 		if (chdat->tx) {
175 			dma_cache_maint(phys_to_virt((u32)chdat->dma_addr),
176 					chdat->transfer_len, DMA_TO_DEVICE);
177 			musb_write_fifo(hw_ep, pio, buf);
178 		} else {
179 			musb_read_fifo(hw_ep, pio, buf);
180 			dma_cache_maint(phys_to_virt((u32)chdat->dma_addr),
181 					chdat->transfer_len, DMA_FROM_DEVICE);
182 		}
183 		channel->actual_len += pio;
184 	}
185 
186 	if (!tusb_dma->multichannel)
187 		tusb_omap_free_shared_dmareq(chdat);
188 
189 	channel->status = MUSB_DMA_STATUS_FREE;
190 
191 	/* Handle only RX callbacks here. TX callbacks must be handled based
192 	 * on the TUSB DMA status interrupt.
193 	 * REVISIT: Use both TUSB DMA status interrupt and OMAP DMA callback
194 	 * interrupt for RX and TX.
195 	 */
196 	if (!chdat->tx)
197 		musb_dma_completion(musb, chdat->epnum, chdat->tx);
198 
199 	/* We must terminate short tx transfers manually by setting TXPKTRDY.
200 	 * REVISIT: This same problem may occur with other MUSB dma as well.
201 	 * Easy to test with g_ether by pinging the MUSB board with ping -s54.
202 	 */
203 	if ((chdat->transfer_len < chdat->packet_sz)
204 			|| (chdat->transfer_len % chdat->packet_sz != 0)) {
205 		u16	csr;
206 
207 		if (chdat->tx) {
208 			DBG(3, "terminating short tx packet\n");
209 			musb_ep_select(mbase, chdat->epnum);
210 			csr = musb_readw(hw_ep->regs, MUSB_TXCSR);
211 			csr |= MUSB_TXCSR_MODE | MUSB_TXCSR_TXPKTRDY
212 				| MUSB_TXCSR_P_WZC_BITS;
213 			musb_writew(hw_ep->regs, MUSB_TXCSR, csr);
214 		}
215 	}
216 
217 	spin_unlock_irqrestore(&musb->lock, flags);
218 }
219 
220 static int tusb_omap_dma_program(struct dma_channel *channel, u16 packet_sz,
221 				u8 rndis_mode, dma_addr_t dma_addr, u32 len)
222 {
223 	struct tusb_omap_dma_ch		*chdat = to_chdat(channel);
224 	struct tusb_omap_dma		*tusb_dma = chdat->tusb_dma;
225 	struct musb			*musb = chdat->musb;
226 	struct musb_hw_ep		*hw_ep = chdat->hw_ep;
227 	void __iomem			*mbase = musb->mregs;
228 	void __iomem			*ep_conf = hw_ep->conf;
229 	dma_addr_t			fifo = hw_ep->fifo_sync;
230 	struct omap_dma_channel_params	dma_params;
231 	u32				dma_remaining;
232 	int				src_burst, dst_burst;
233 	u16				csr;
234 	int				ch;
235 	s8				dmareq;
236 	s8				sync_dev;
237 
238 	if (unlikely(dma_addr & 0x1) || (len < 32) || (len > packet_sz))
239 		return false;
240 
241 	/*
242 	 * HW issue #10: Async dma will eventually corrupt the XFR_SIZE
243 	 * register which will cause missed DMA interrupt. We could try to
244 	 * use a timer for the callback, but it is unsafe as the XFR_SIZE
245 	 * register is corrupt, and we won't know if the DMA worked.
246 	 */
247 	if (dma_addr & 0x2)
248 		return false;
249 
250 	/*
251 	 * Because of HW issue #10, it seems like mixing sync DMA and async
252 	 * PIO access can confuse the DMA. Make sure XFR_SIZE is reset before
253 	 * using the channel for DMA.
254 	 */
255 	if (chdat->tx)
256 		dma_remaining = musb_readl(ep_conf, TUSB_EP_TX_OFFSET);
257 	else
258 		dma_remaining = musb_readl(ep_conf, TUSB_EP_RX_OFFSET);
259 
260 	dma_remaining = TUSB_EP_CONFIG_XFR_SIZE(dma_remaining);
261 	if (dma_remaining) {
262 		DBG(2, "Busy %s dma ch%i, not using: %08x\n",
263 			chdat->tx ? "tx" : "rx", chdat->ch,
264 			dma_remaining);
265 		return false;
266 	}
267 
268 	chdat->transfer_len = len & ~0x1f;
269 
270 	if (len < packet_sz)
271 		chdat->transfer_packet_sz = chdat->transfer_len;
272 	else
273 		chdat->transfer_packet_sz = packet_sz;
274 
275 	if (tusb_dma->multichannel) {
276 		ch = chdat->ch;
277 		dmareq = chdat->dmareq;
278 		sync_dev = chdat->sync_dev;
279 	} else {
280 		if (tusb_omap_use_shared_dmareq(chdat) != 0) {
281 			DBG(3, "could not get dma for ep%i\n", chdat->epnum);
282 			return false;
283 		}
284 		if (tusb_dma->ch < 0) {
285 			/* REVISIT: This should get blocked earlier, happens
286 			 * with MSC ErrorRecoveryTest
287 			 */
288 			WARN_ON(1);
289 			return false;
290 		}
291 
292 		ch = tusb_dma->ch;
293 		dmareq = tusb_dma->dmareq;
294 		sync_dev = tusb_dma->sync_dev;
295 		omap_set_dma_callback(ch, tusb_omap_dma_cb, channel);
296 	}
297 
298 	chdat->packet_sz = packet_sz;
299 	chdat->len = len;
300 	channel->actual_len = 0;
301 	chdat->dma_addr = (void __iomem *)dma_addr;
302 	channel->status = MUSB_DMA_STATUS_BUSY;
303 
304 	/* Since we're recycling dma areas, we need to clean or invalidate */
305 	if (chdat->tx)
306 		dma_cache_maint(phys_to_virt(dma_addr), len, DMA_TO_DEVICE);
307 	else
308 		dma_cache_maint(phys_to_virt(dma_addr), len, DMA_FROM_DEVICE);
309 
310 	/* Use 16-bit transfer if dma_addr is not 32-bit aligned */
311 	if ((dma_addr & 0x3) == 0) {
312 		dma_params.data_type = OMAP_DMA_DATA_TYPE_S32;
313 		dma_params.elem_count = 8;		/* Elements in frame */
314 	} else {
315 		dma_params.data_type = OMAP_DMA_DATA_TYPE_S16;
316 		dma_params.elem_count = 16;		/* Elements in frame */
317 		fifo = hw_ep->fifo_async;
318 	}
319 
320 	dma_params.frame_count	= chdat->transfer_len / 32; /* Burst sz frame */
321 
322 	DBG(3, "ep%i %s dma ch%i dma: %08x len: %u(%u) packet_sz: %i(%i)\n",
323 		chdat->epnum, chdat->tx ? "tx" : "rx",
324 		ch, dma_addr, chdat->transfer_len, len,
325 		chdat->transfer_packet_sz, packet_sz);
326 
327 	/*
328 	 * Prepare omap DMA for transfer
329 	 */
330 	if (chdat->tx) {
331 		dma_params.src_amode	= OMAP_DMA_AMODE_POST_INC;
332 		dma_params.src_start	= (unsigned long)dma_addr;
333 		dma_params.src_ei	= 0;
334 		dma_params.src_fi	= 0;
335 
336 		dma_params.dst_amode	= OMAP_DMA_AMODE_DOUBLE_IDX;
337 		dma_params.dst_start	= (unsigned long)fifo;
338 		dma_params.dst_ei	= 1;
339 		dma_params.dst_fi	= -31;	/* Loop 32 byte window */
340 
341 		dma_params.trigger	= sync_dev;
342 		dma_params.sync_mode	= OMAP_DMA_SYNC_FRAME;
343 		dma_params.src_or_dst_synch	= 0;	/* Dest sync */
344 
345 		src_burst = OMAP_DMA_DATA_BURST_16;	/* 16x32 read */
346 		dst_burst = OMAP_DMA_DATA_BURST_8;	/* 8x32 write */
347 	} else {
348 		dma_params.src_amode	= OMAP_DMA_AMODE_DOUBLE_IDX;
349 		dma_params.src_start	= (unsigned long)fifo;
350 		dma_params.src_ei	= 1;
351 		dma_params.src_fi	= -31;	/* Loop 32 byte window */
352 
353 		dma_params.dst_amode	= OMAP_DMA_AMODE_POST_INC;
354 		dma_params.dst_start	= (unsigned long)dma_addr;
355 		dma_params.dst_ei	= 0;
356 		dma_params.dst_fi	= 0;
357 
358 		dma_params.trigger	= sync_dev;
359 		dma_params.sync_mode	= OMAP_DMA_SYNC_FRAME;
360 		dma_params.src_or_dst_synch	= 1;	/* Source sync */
361 
362 		src_burst = OMAP_DMA_DATA_BURST_8;	/* 8x32 read */
363 		dst_burst = OMAP_DMA_DATA_BURST_16;	/* 16x32 write */
364 	}
365 
366 	DBG(3, "ep%i %s using %i-bit %s dma from 0x%08lx to 0x%08lx\n",
367 		chdat->epnum, chdat->tx ? "tx" : "rx",
368 		(dma_params.data_type == OMAP_DMA_DATA_TYPE_S32) ? 32 : 16,
369 		((dma_addr & 0x3) == 0) ? "sync" : "async",
370 		dma_params.src_start, dma_params.dst_start);
371 
372 	omap_set_dma_params(ch, &dma_params);
373 	omap_set_dma_src_burst_mode(ch, src_burst);
374 	omap_set_dma_dest_burst_mode(ch, dst_burst);
375 	omap_set_dma_write_mode(ch, OMAP_DMA_WRITE_LAST_NON_POSTED);
376 
377 	/*
378 	 * Prepare MUSB for DMA transfer
379 	 */
380 	if (chdat->tx) {
381 		musb_ep_select(mbase, chdat->epnum);
382 		csr = musb_readw(hw_ep->regs, MUSB_TXCSR);
383 		csr |= (MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB
384 			| MUSB_TXCSR_DMAMODE | MUSB_TXCSR_MODE);
385 		csr &= ~MUSB_TXCSR_P_UNDERRUN;
386 		musb_writew(hw_ep->regs, MUSB_TXCSR, csr);
387 	} else {
388 		musb_ep_select(mbase, chdat->epnum);
389 		csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
390 		csr |= MUSB_RXCSR_DMAENAB;
391 		csr &= ~(MUSB_RXCSR_AUTOCLEAR | MUSB_RXCSR_DMAMODE);
392 		musb_writew(hw_ep->regs, MUSB_RXCSR,
393 			csr | MUSB_RXCSR_P_WZC_BITS);
394 	}
395 
396 	/*
397 	 * Start DMA transfer
398 	 */
399 	omap_start_dma(ch);
400 
401 	if (chdat->tx) {
402 		/* Send transfer_packet_sz packets at a time */
403 		musb_writel(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET,
404 			chdat->transfer_packet_sz);
405 
406 		musb_writel(ep_conf, TUSB_EP_TX_OFFSET,
407 			TUSB_EP_CONFIG_XFR_SIZE(chdat->transfer_len));
408 	} else {
409 		/* Receive transfer_packet_sz packets at a time */
410 		musb_writel(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET,
411 			chdat->transfer_packet_sz << 16);
412 
413 		musb_writel(ep_conf, TUSB_EP_RX_OFFSET,
414 			TUSB_EP_CONFIG_XFR_SIZE(chdat->transfer_len));
415 	}
416 
417 	return true;
418 }
419 
420 static int tusb_omap_dma_abort(struct dma_channel *channel)
421 {
422 	struct tusb_omap_dma_ch	*chdat = to_chdat(channel);
423 	struct tusb_omap_dma	*tusb_dma = chdat->tusb_dma;
424 
425 	if (!tusb_dma->multichannel) {
426 		if (tusb_dma->ch >= 0) {
427 			omap_stop_dma(tusb_dma->ch);
428 			omap_free_dma(tusb_dma->ch);
429 			tusb_dma->ch = -1;
430 		}
431 
432 		tusb_dma->dmareq = -1;
433 		tusb_dma->sync_dev = -1;
434 	}
435 
436 	channel->status = MUSB_DMA_STATUS_FREE;
437 
438 	return 0;
439 }
440 
441 static inline int tusb_omap_dma_allocate_dmareq(struct tusb_omap_dma_ch *chdat)
442 {
443 	u32		reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
444 	int		i, dmareq_nr = -1;
445 
446 	const int sync_dev[6] = {
447 		OMAP24XX_DMA_EXT_DMAREQ0,
448 		OMAP24XX_DMA_EXT_DMAREQ1,
449 		OMAP242X_DMA_EXT_DMAREQ2,
450 		OMAP242X_DMA_EXT_DMAREQ3,
451 		OMAP242X_DMA_EXT_DMAREQ4,
452 		OMAP242X_DMA_EXT_DMAREQ5,
453 	};
454 
455 	for (i = 0; i < MAX_DMAREQ; i++) {
456 		int cur = (reg & (0xf << (i * 5))) >> (i * 5);
457 		if (cur == 0) {
458 			dmareq_nr = i;
459 			break;
460 		}
461 	}
462 
463 	if (dmareq_nr == -1)
464 		return -EAGAIN;
465 
466 	reg |= (chdat->epnum << (dmareq_nr * 5));
467 	if (chdat->tx)
468 		reg |= ((1 << 4) << (dmareq_nr * 5));
469 	musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, reg);
470 
471 	chdat->dmareq = dmareq_nr;
472 	chdat->sync_dev = sync_dev[chdat->dmareq];
473 
474 	return 0;
475 }
476 
477 static inline void tusb_omap_dma_free_dmareq(struct tusb_omap_dma_ch *chdat)
478 {
479 	u32 reg;
480 
481 	if (!chdat || chdat->dmareq < 0)
482 		return;
483 
484 	reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
485 	reg &= ~(0x1f << (chdat->dmareq * 5));
486 	musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, reg);
487 
488 	chdat->dmareq = -1;
489 	chdat->sync_dev = -1;
490 }
491 
492 static struct dma_channel *dma_channel_pool[MAX_DMAREQ];
493 
494 static struct dma_channel *
495 tusb_omap_dma_allocate(struct dma_controller *c,
496 		struct musb_hw_ep *hw_ep,
497 		u8 tx)
498 {
499 	int ret, i;
500 	const char		*dev_name;
501 	struct tusb_omap_dma	*tusb_dma;
502 	struct musb		*musb;
503 	void __iomem		*tbase;
504 	struct dma_channel	*channel = NULL;
505 	struct tusb_omap_dma_ch	*chdat = NULL;
506 	u32			reg;
507 
508 	tusb_dma = container_of(c, struct tusb_omap_dma, controller);
509 	musb = tusb_dma->musb;
510 	tbase = musb->ctrl_base;
511 
512 	reg = musb_readl(tbase, TUSB_DMA_INT_MASK);
513 	if (tx)
514 		reg &= ~(1 << hw_ep->epnum);
515 	else
516 		reg &= ~(1 << (hw_ep->epnum + 15));
517 	musb_writel(tbase, TUSB_DMA_INT_MASK, reg);
518 
519 	/* REVISIT: Why does dmareq5 not work? */
520 	if (hw_ep->epnum == 0) {
521 		DBG(3, "Not allowing DMA for ep0 %s\n", tx ? "tx" : "rx");
522 		return NULL;
523 	}
524 
525 	for (i = 0; i < MAX_DMAREQ; i++) {
526 		struct dma_channel *ch = dma_channel_pool[i];
527 		if (ch->status == MUSB_DMA_STATUS_UNKNOWN) {
528 			ch->status = MUSB_DMA_STATUS_FREE;
529 			channel = ch;
530 			chdat = ch->private_data;
531 			break;
532 		}
533 	}
534 
535 	if (!channel)
536 		return NULL;
537 
538 	if (tx) {
539 		chdat->tx = 1;
540 		dev_name = "TUSB transmit";
541 	} else {
542 		chdat->tx = 0;
543 		dev_name = "TUSB receive";
544 	}
545 
546 	chdat->musb = tusb_dma->musb;
547 	chdat->tbase = tusb_dma->tbase;
548 	chdat->hw_ep = hw_ep;
549 	chdat->epnum = hw_ep->epnum;
550 	chdat->dmareq = -1;
551 	chdat->completed_len = 0;
552 	chdat->tusb_dma = tusb_dma;
553 
554 	channel->max_len = 0x7fffffff;
555 	channel->desired_mode = 0;
556 	channel->actual_len = 0;
557 
558 	if (tusb_dma->multichannel) {
559 		ret = tusb_omap_dma_allocate_dmareq(chdat);
560 		if (ret != 0)
561 			goto free_dmareq;
562 
563 		ret = omap_request_dma(chdat->sync_dev, dev_name,
564 				tusb_omap_dma_cb, channel, &chdat->ch);
565 		if (ret != 0)
566 			goto free_dmareq;
567 	} else if (tusb_dma->ch == -1) {
568 		tusb_dma->dmareq = 0;
569 		tusb_dma->sync_dev = OMAP24XX_DMA_EXT_DMAREQ0;
570 
571 		/* Callback data gets set later in the shared dmareq case */
572 		ret = omap_request_dma(tusb_dma->sync_dev, "TUSB shared",
573 				tusb_omap_dma_cb, NULL, &tusb_dma->ch);
574 		if (ret != 0)
575 			goto free_dmareq;
576 
577 		chdat->dmareq = -1;
578 		chdat->ch = -1;
579 	}
580 
581 	DBG(3, "ep%i %s dma: %s dma%i dmareq%i sync%i\n",
582 		chdat->epnum,
583 		chdat->tx ? "tx" : "rx",
584 		chdat->ch >= 0 ? "dedicated" : "shared",
585 		chdat->ch >= 0 ? chdat->ch : tusb_dma->ch,
586 		chdat->dmareq >= 0 ? chdat->dmareq : tusb_dma->dmareq,
587 		chdat->sync_dev >= 0 ? chdat->sync_dev : tusb_dma->sync_dev);
588 
589 	return channel;
590 
591 free_dmareq:
592 	tusb_omap_dma_free_dmareq(chdat);
593 
594 	DBG(3, "ep%i: Could not get a DMA channel\n", chdat->epnum);
595 	channel->status = MUSB_DMA_STATUS_UNKNOWN;
596 
597 	return NULL;
598 }
599 
600 static void tusb_omap_dma_release(struct dma_channel *channel)
601 {
602 	struct tusb_omap_dma_ch	*chdat = to_chdat(channel);
603 	struct musb		*musb = chdat->musb;
604 	void __iomem		*tbase = musb->ctrl_base;
605 	u32			reg;
606 
607 	DBG(3, "ep%i ch%i\n", chdat->epnum, chdat->ch);
608 
609 	reg = musb_readl(tbase, TUSB_DMA_INT_MASK);
610 	if (chdat->tx)
611 		reg |= (1 << chdat->epnum);
612 	else
613 		reg |= (1 << (chdat->epnum + 15));
614 	musb_writel(tbase, TUSB_DMA_INT_MASK, reg);
615 
616 	reg = musb_readl(tbase, TUSB_DMA_INT_CLEAR);
617 	if (chdat->tx)
618 		reg |= (1 << chdat->epnum);
619 	else
620 		reg |= (1 << (chdat->epnum + 15));
621 	musb_writel(tbase, TUSB_DMA_INT_CLEAR, reg);
622 
623 	channel->status = MUSB_DMA_STATUS_UNKNOWN;
624 
625 	if (chdat->ch >= 0) {
626 		omap_stop_dma(chdat->ch);
627 		omap_free_dma(chdat->ch);
628 		chdat->ch = -1;
629 	}
630 
631 	if (chdat->dmareq >= 0)
632 		tusb_omap_dma_free_dmareq(chdat);
633 
634 	channel = NULL;
635 }
636 
637 void dma_controller_destroy(struct dma_controller *c)
638 {
639 	struct tusb_omap_dma	*tusb_dma;
640 	int			i;
641 
642 	tusb_dma = container_of(c, struct tusb_omap_dma, controller);
643 	for (i = 0; i < MAX_DMAREQ; i++) {
644 		struct dma_channel *ch = dma_channel_pool[i];
645 		if (ch) {
646 			kfree(ch->private_data);
647 			kfree(ch);
648 		}
649 	}
650 
651 	if (!tusb_dma->multichannel && tusb_dma && tusb_dma->ch >= 0)
652 		omap_free_dma(tusb_dma->ch);
653 
654 	kfree(tusb_dma);
655 }
656 
657 struct dma_controller *__init
658 dma_controller_create(struct musb *musb, void __iomem *base)
659 {
660 	void __iomem		*tbase = musb->ctrl_base;
661 	struct tusb_omap_dma	*tusb_dma;
662 	int			i;
663 
664 	/* REVISIT: Get dmareq lines used from board-*.c */
665 
666 	musb_writel(musb->ctrl_base, TUSB_DMA_INT_MASK, 0x7fffffff);
667 	musb_writel(musb->ctrl_base, TUSB_DMA_EP_MAP, 0);
668 
669 	musb_writel(tbase, TUSB_DMA_REQ_CONF,
670 		TUSB_DMA_REQ_CONF_BURST_SIZE(2)
671 		| TUSB_DMA_REQ_CONF_DMA_REQ_EN(0x3f)
672 		| TUSB_DMA_REQ_CONF_DMA_REQ_ASSER(2));
673 
674 	tusb_dma = kzalloc(sizeof(struct tusb_omap_dma), GFP_KERNEL);
675 	if (!tusb_dma)
676 		goto cleanup;
677 
678 	tusb_dma->musb = musb;
679 	tusb_dma->tbase = musb->ctrl_base;
680 
681 	tusb_dma->ch = -1;
682 	tusb_dma->dmareq = -1;
683 	tusb_dma->sync_dev = -1;
684 
685 	tusb_dma->controller.start = tusb_omap_dma_start;
686 	tusb_dma->controller.stop = tusb_omap_dma_stop;
687 	tusb_dma->controller.channel_alloc = tusb_omap_dma_allocate;
688 	tusb_dma->controller.channel_release = tusb_omap_dma_release;
689 	tusb_dma->controller.channel_program = tusb_omap_dma_program;
690 	tusb_dma->controller.channel_abort = tusb_omap_dma_abort;
691 
692 	if (tusb_get_revision(musb) >= TUSB_REV_30)
693 		tusb_dma->multichannel = 1;
694 
695 	for (i = 0; i < MAX_DMAREQ; i++) {
696 		struct dma_channel	*ch;
697 		struct tusb_omap_dma_ch	*chdat;
698 
699 		ch = kzalloc(sizeof(struct dma_channel), GFP_KERNEL);
700 		if (!ch)
701 			goto cleanup;
702 
703 		dma_channel_pool[i] = ch;
704 
705 		chdat = kzalloc(sizeof(struct tusb_omap_dma_ch), GFP_KERNEL);
706 		if (!chdat)
707 			goto cleanup;
708 
709 		ch->status = MUSB_DMA_STATUS_UNKNOWN;
710 		ch->private_data = chdat;
711 	}
712 
713 	return &tusb_dma->controller;
714 
715 cleanup:
716 	dma_controller_destroy(&tusb_dma->controller);
717 
718 	return NULL;
719 }
720