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Nicolas Ferredc78baa2009-07-03 19:24:33 +02001/*
2 * Header file for the Atmel AHB DMA Controller driver
3 *
4 * Copyright (C) 2008 Atmel Corporation
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 */
11#ifndef AT_HDMAC_REGS_H
12#define AT_HDMAC_REGS_H
13
Arnd Bergmann7cdc39e2012-08-24 15:10:04 +020014#include <linux/platform_data/dma-atmel.h>
Nicolas Ferredc78baa2009-07-03 19:24:33 +020015
16#define AT_DMA_MAX_NR_CHANNELS 8
17
18
19#define AT_DMA_GCFG 0x00 /* Global Configuration Register */
20#define AT_DMA_IF_BIGEND(i) (0x1 << (i)) /* AHB-Lite Interface i in Big-endian mode */
21#define AT_DMA_ARB_CFG (0x1 << 4) /* Arbiter mode. */
22#define AT_DMA_ARB_CFG_FIXED (0x0 << 4)
23#define AT_DMA_ARB_CFG_ROUND_ROBIN (0x1 << 4)
24
25#define AT_DMA_EN 0x04 /* Controller Enable Register */
26#define AT_DMA_ENABLE (0x1 << 0)
27
28#define AT_DMA_SREQ 0x08 /* Software Single Request Register */
29#define AT_DMA_SSREQ(x) (0x1 << ((x) << 1)) /* Request a source single transfer on channel x */
30#define AT_DMA_DSREQ(x) (0x1 << (1 + ((x) << 1))) /* Request a destination single transfer on channel x */
31
32#define AT_DMA_CREQ 0x0C /* Software Chunk Transfer Request Register */
33#define AT_DMA_SCREQ(x) (0x1 << ((x) << 1)) /* Request a source chunk transfer on channel x */
34#define AT_DMA_DCREQ(x) (0x1 << (1 + ((x) << 1))) /* Request a destination chunk transfer on channel x */
35
36#define AT_DMA_LAST 0x10 /* Software Last Transfer Flag Register */
37#define AT_DMA_SLAST(x) (0x1 << ((x) << 1)) /* This src rq is last tx of buffer on channel x */
38#define AT_DMA_DLAST(x) (0x1 << (1 + ((x) << 1))) /* This dst rq is last tx of buffer on channel x */
39
40#define AT_DMA_SYNC 0x14 /* Request Synchronization Register */
41#define AT_DMA_SYR(h) (0x1 << (h)) /* Synchronize handshake line h */
42
43/* Error, Chained Buffer transfer completed and Buffer transfer completed Interrupt registers */
44#define AT_DMA_EBCIER 0x18 /* Enable register */
45#define AT_DMA_EBCIDR 0x1C /* Disable register */
46#define AT_DMA_EBCIMR 0x20 /* Mask Register */
47#define AT_DMA_EBCISR 0x24 /* Status Register */
48#define AT_DMA_CBTC_OFFSET 8
49#define AT_DMA_ERR_OFFSET 16
50#define AT_DMA_BTC(x) (0x1 << (x))
51#define AT_DMA_CBTC(x) (0x1 << (AT_DMA_CBTC_OFFSET + (x)))
52#define AT_DMA_ERR(x) (0x1 << (AT_DMA_ERR_OFFSET + (x)))
53
54#define AT_DMA_CHER 0x28 /* Channel Handler Enable Register */
55#define AT_DMA_ENA(x) (0x1 << (x))
56#define AT_DMA_SUSP(x) (0x1 << ( 8 + (x)))
57#define AT_DMA_KEEP(x) (0x1 << (24 + (x)))
58
59#define AT_DMA_CHDR 0x2C /* Channel Handler Disable Register */
60#define AT_DMA_DIS(x) (0x1 << (x))
61#define AT_DMA_RES(x) (0x1 << ( 8 + (x)))
62
63#define AT_DMA_CHSR 0x30 /* Channel Handler Status Register */
64#define AT_DMA_EMPT(x) (0x1 << (16 + (x)))
65#define AT_DMA_STAL(x) (0x1 << (24 + (x)))
66
67
68#define AT_DMA_CH_REGS_BASE 0x3C /* Channel registers base address */
69#define ch_regs(x) (AT_DMA_CH_REGS_BASE + (x) * 0x28) /* Channel x base addr */
70
71/* Hardware register offset for each channel */
72#define ATC_SADDR_OFFSET 0x00 /* Source Address Register */
73#define ATC_DADDR_OFFSET 0x04 /* Destination Address Register */
74#define ATC_DSCR_OFFSET 0x08 /* Descriptor Address Register */
75#define ATC_CTRLA_OFFSET 0x0C /* Control A Register */
76#define ATC_CTRLB_OFFSET 0x10 /* Control B Register */
77#define ATC_CFG_OFFSET 0x14 /* Configuration Register */
78#define ATC_SPIP_OFFSET 0x18 /* Src PIP Configuration Register */
79#define ATC_DPIP_OFFSET 0x1C /* Dst PIP Configuration Register */
80
81
82/* Bitfield definitions */
83
84/* Bitfields in DSCR */
85#define ATC_DSCR_IF(i) (0x3 & (i)) /* Dsc feched via AHB-Lite Interface i */
86
87/* Bitfields in CTRLA */
88#define ATC_BTSIZE_MAX 0xFFFFUL /* Maximum Buffer Transfer Size */
89#define ATC_BTSIZE(x) (ATC_BTSIZE_MAX & (x)) /* Buffer Transfer Size */
Nicolas Ferre1dd1ea82012-05-10 12:17:41 +020090#define ATC_SCSIZE_MASK (0x7 << 16) /* Source Chunk Transfer Size */
91#define ATC_SCSIZE(x) (ATC_SCSIZE_MASK & ((x) << 16))
92#define ATC_SCSIZE_1 (0x0 << 16)
93#define ATC_SCSIZE_4 (0x1 << 16)
94#define ATC_SCSIZE_8 (0x2 << 16)
95#define ATC_SCSIZE_16 (0x3 << 16)
96#define ATC_SCSIZE_32 (0x4 << 16)
97#define ATC_SCSIZE_64 (0x5 << 16)
98#define ATC_SCSIZE_128 (0x6 << 16)
99#define ATC_SCSIZE_256 (0x7 << 16)
100#define ATC_DCSIZE_MASK (0x7 << 20) /* Destination Chunk Transfer Size */
101#define ATC_DCSIZE(x) (ATC_DCSIZE_MASK & ((x) << 20))
102#define ATC_DCSIZE_1 (0x0 << 20)
103#define ATC_DCSIZE_4 (0x1 << 20)
104#define ATC_DCSIZE_8 (0x2 << 20)
105#define ATC_DCSIZE_16 (0x3 << 20)
106#define ATC_DCSIZE_32 (0x4 << 20)
107#define ATC_DCSIZE_64 (0x5 << 20)
108#define ATC_DCSIZE_128 (0x6 << 20)
109#define ATC_DCSIZE_256 (0x7 << 20)
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200110#define ATC_SRC_WIDTH_MASK (0x3 << 24) /* Source Single Transfer Size */
Nicolas Ferre808347f2009-07-22 20:04:45 +0200111#define ATC_SRC_WIDTH(x) ((x) << 24)
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200112#define ATC_SRC_WIDTH_BYTE (0x0 << 24)
113#define ATC_SRC_WIDTH_HALFWORD (0x1 << 24)
114#define ATC_SRC_WIDTH_WORD (0x2 << 24)
115#define ATC_DST_WIDTH_MASK (0x3 << 28) /* Destination Single Transfer Size */
Nicolas Ferre808347f2009-07-22 20:04:45 +0200116#define ATC_DST_WIDTH(x) ((x) << 28)
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200117#define ATC_DST_WIDTH_BYTE (0x0 << 28)
118#define ATC_DST_WIDTH_HALFWORD (0x1 << 28)
119#define ATC_DST_WIDTH_WORD (0x2 << 28)
120#define ATC_DONE (0x1 << 31) /* Tx Done (only written back in descriptor) */
121
122/* Bitfields in CTRLB */
123#define ATC_SIF(i) (0x3 & (i)) /* Src tx done via AHB-Lite Interface i */
124#define ATC_DIF(i) ((0x3 & (i)) << 4) /* Dst tx done via AHB-Lite Interface i */
Nicolas Ferreae14d4b2011-04-30 16:57:49 +0200125 /* Specify AHB interfaces */
126#define AT_DMA_MEM_IF 0 /* interface 0 as memory interface */
127#define AT_DMA_PER_IF 1 /* interface 1 as peripheral interface */
128
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200129#define ATC_SRC_PIP (0x1 << 8) /* Source Picture-in-Picture enabled */
130#define ATC_DST_PIP (0x1 << 12) /* Destination Picture-in-Picture enabled */
131#define ATC_SRC_DSCR_DIS (0x1 << 16) /* Src Descriptor fetch disable */
132#define ATC_DST_DSCR_DIS (0x1 << 20) /* Dst Descriptor fetch disable */
133#define ATC_FC_MASK (0x7 << 21) /* Choose Flow Controller */
134#define ATC_FC_MEM2MEM (0x0 << 21) /* Mem-to-Mem (DMA) */
135#define ATC_FC_MEM2PER (0x1 << 21) /* Mem-to-Periph (DMA) */
136#define ATC_FC_PER2MEM (0x2 << 21) /* Periph-to-Mem (DMA) */
137#define ATC_FC_PER2PER (0x3 << 21) /* Periph-to-Periph (DMA) */
138#define ATC_FC_PER2MEM_PER (0x4 << 21) /* Periph-to-Mem (Peripheral) */
139#define ATC_FC_MEM2PER_PER (0x5 << 21) /* Mem-to-Periph (Peripheral) */
Nicolas Ferre808347f2009-07-22 20:04:45 +0200140#define ATC_FC_PER2PER_SRCPER (0x6 << 21) /* Periph-to-Periph (Src Peripheral) */
141#define ATC_FC_PER2PER_DSTPER (0x7 << 21) /* Periph-to-Periph (Dst Peripheral) */
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200142#define ATC_SRC_ADDR_MODE_MASK (0x3 << 24)
143#define ATC_SRC_ADDR_MODE_INCR (0x0 << 24) /* Incrementing Mode */
144#define ATC_SRC_ADDR_MODE_DECR (0x1 << 24) /* Decrementing Mode */
145#define ATC_SRC_ADDR_MODE_FIXED (0x2 << 24) /* Fixed Mode */
146#define ATC_DST_ADDR_MODE_MASK (0x3 << 28)
147#define ATC_DST_ADDR_MODE_INCR (0x0 << 28) /* Incrementing Mode */
148#define ATC_DST_ADDR_MODE_DECR (0x1 << 28) /* Decrementing Mode */
149#define ATC_DST_ADDR_MODE_FIXED (0x2 << 28) /* Fixed Mode */
150#define ATC_IEN (0x1 << 30) /* BTC interrupt enable (active low) */
151#define ATC_AUTO (0x1 << 31) /* Auto multiple buffer tx enable */
152
153/* Bitfields in CFG */
Nicolas Ferre808347f2009-07-22 20:04:45 +0200154/* are in at_hdmac.h */
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200155
156/* Bitfields in SPIP */
157#define ATC_SPIP_HOLE(x) (0xFFFFU & (x))
158#define ATC_SPIP_BOUNDARY(x) ((0x3FF & (x)) << 16)
159
160/* Bitfields in DPIP */
161#define ATC_DPIP_HOLE(x) (0xFFFFU & (x))
162#define ATC_DPIP_BOUNDARY(x) ((0x3FF & (x)) << 16)
163
164
165/*-- descriptors -----------------------------------------------------*/
166
167/* LLI == Linked List Item; aka DMA buffer descriptor */
168struct at_lli {
169 /* values that are not changed by hardware */
170 dma_addr_t saddr;
171 dma_addr_t daddr;
172 /* value that may get written back: */
173 u32 ctrla;
174 /* more values that are not changed by hardware */
175 u32 ctrlb;
176 dma_addr_t dscr; /* chain to next lli */
177};
178
179/**
180 * struct at_desc - software descriptor
181 * @at_lli: hardware lli structure
182 * @txd: support for the async_tx api
183 * @desc_node: node on the channed descriptors list
184 * @len: total transaction bytecount
185 */
186struct at_desc {
187 /* FIRST values the hardware uses */
188 struct at_lli lli;
189
190 /* THEN values for driver housekeeping */
Dan Williams285a3c72009-09-08 17:53:03 -0700191 struct list_head tx_list;
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200192 struct dma_async_tx_descriptor txd;
193 struct list_head desc_node;
194 size_t len;
195};
196
197static inline struct at_desc *
198txd_to_at_desc(struct dma_async_tx_descriptor *txd)
199{
200 return container_of(txd, struct at_desc, txd);
201}
202
203
204/*-- Channels --------------------------------------------------------*/
205
206/**
Nicolas Ferre53830cc2011-04-30 16:57:46 +0200207 * atc_status - information bits stored in channel status flag
208 *
209 * Manipulated with atomic operations.
210 */
211enum atc_status {
212 ATC_IS_ERROR = 0,
Nicolas Ferre23b5e3a2011-05-06 19:56:52 +0200213 ATC_IS_PAUSED = 1,
Nicolas Ferre53830cc2011-04-30 16:57:46 +0200214 ATC_IS_CYCLIC = 24,
215};
216
217/**
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200218 * struct at_dma_chan - internal representation of an Atmel HDMAC channel
219 * @chan_common: common dmaengine channel object members
220 * @device: parent device
221 * @ch_regs: memory mapped register base
222 * @mask: channel index in a mask
Ludovic Desrochesbbe89c82013-04-19 09:11:18 +0000223 * @per_if: peripheral interface
224 * @mem_if: memory interface
Nicolas Ferre53830cc2011-04-30 16:57:46 +0200225 * @status: transmit status information from irq/prep* functions
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200226 * to tasklet (use atomic operations)
227 * @tasklet: bottom half to finish transaction work
Nicolas Ferrec0ba5942011-07-27 12:21:29 +0000228 * @save_cfg: configuration register that is saved on suspend/resume cycle
229 * @save_dscr: for cyclic operations, preserve next descriptor address in
230 * the cyclic list on suspend/resume cycle
Nicolas Ferrebeeaa102012-03-14 12:41:43 +0100231 * @dma_sconfig: configuration for slave transfers, passed via DMA_SLAVE_CONFIG
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200232 * @lock: serializes enqueue/dequeue operations to descriptors lists
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200233 * @active_list: list of descriptors dmaengine is being running on
234 * @queue: list of descriptors ready to be submitted to engine
235 * @free_list: list of descriptors usable by the channel
236 * @descs_allocated: records the actual size of the descriptor pool
237 */
238struct at_dma_chan {
239 struct dma_chan chan_common;
240 struct at_dma *device;
241 void __iomem *ch_regs;
242 u8 mask;
Ludovic Desrochesbbe89c82013-04-19 09:11:18 +0000243 u8 per_if;
244 u8 mem_if;
Nicolas Ferre53830cc2011-04-30 16:57:46 +0200245 unsigned long status;
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200246 struct tasklet_struct tasklet;
Nicolas Ferrec0ba5942011-07-27 12:21:29 +0000247 u32 save_cfg;
248 u32 save_dscr;
Nicolas Ferrebeeaa102012-03-14 12:41:43 +0100249 struct dma_slave_config dma_sconfig;
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200250
251 spinlock_t lock;
252
253 /* these other elements are all protected by lock */
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200254 struct list_head active_list;
255 struct list_head queue;
256 struct list_head free_list;
257 unsigned int descs_allocated;
258};
259
260#define channel_readl(atchan, name) \
261 __raw_readl((atchan)->ch_regs + ATC_##name##_OFFSET)
262
263#define channel_writel(atchan, name, val) \
264 __raw_writel((val), (atchan)->ch_regs + ATC_##name##_OFFSET)
265
266static inline struct at_dma_chan *to_at_dma_chan(struct dma_chan *dchan)
267{
268 return container_of(dchan, struct at_dma_chan, chan_common);
269}
270
Nicolas Ferrebeeaa102012-03-14 12:41:43 +0100271/*
272 * Fix sconfig's burst size according to at_hdmac. We need to convert them as:
273 * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3, 32 -> 4, 64 -> 5, 128 -> 6, 256 -> 7.
274 *
275 * This can be done by finding most significant bit set.
276 */
277static inline void convert_burst(u32 *maxburst)
278{
279 if (*maxburst > 1)
280 *maxburst = fls(*maxburst) - 2;
281 else
282 *maxburst = 0;
283}
284
285/*
286 * Fix sconfig's bus width according to at_hdmac.
287 * 1 byte -> 0, 2 bytes -> 1, 4 bytes -> 2.
288 */
289static inline u8 convert_buswidth(enum dma_slave_buswidth addr_width)
290{
291 switch (addr_width) {
292 case DMA_SLAVE_BUSWIDTH_2_BYTES:
293 return 1;
294 case DMA_SLAVE_BUSWIDTH_4_BYTES:
295 return 2;
296 default:
297 /* For 1 byte width or fallback */
298 return 0;
299 }
300}
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200301
302/*-- Controller ------------------------------------------------------*/
303
304/**
305 * struct at_dma - internal representation of an Atmel HDMA Controller
306 * @chan_common: common dmaengine dma_device object members
Nicolas Ferre67348452011-10-17 14:56:40 +0200307 * @atdma_devtype: identifier of DMA controller compatibility
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200308 * @ch_regs: memory mapped register base
309 * @clk: dma controller clock
Nicolas Ferrec0ba5942011-07-27 12:21:29 +0000310 * @save_imr: interrupt mask register that is saved on suspend/resume cycle
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200311 * @all_chan_mask: all channels availlable in a mask
312 * @dma_desc_pool: base of DMA descriptor region (DMA address)
313 * @chan: channels table to store at_dma_chan structures
314 */
315struct at_dma {
316 struct dma_device dma_common;
317 void __iomem *regs;
318 struct clk *clk;
Nicolas Ferrec0ba5942011-07-27 12:21:29 +0000319 u32 save_imr;
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200320
321 u8 all_chan_mask;
322
323 struct dma_pool *dma_desc_pool;
324 /* AT THE END channels table */
325 struct at_dma_chan chan[0];
326};
327
328#define dma_readl(atdma, name) \
329 __raw_readl((atdma)->regs + AT_DMA_##name)
330#define dma_writel(atdma, name, val) \
331 __raw_writel((val), (atdma)->regs + AT_DMA_##name)
332
333static inline struct at_dma *to_at_dma(struct dma_device *ddev)
334{
335 return container_of(ddev, struct at_dma, dma_common);
336}
337
338
339/*-- Helper functions ------------------------------------------------*/
340
341static struct device *chan2dev(struct dma_chan *chan)
342{
343 return &chan->dev->device;
344}
345static struct device *chan2parent(struct dma_chan *chan)
346{
347 return chan->dev->device.parent;
348}
349
350#if defined(VERBOSE_DEBUG)
351static void vdbg_dump_regs(struct at_dma_chan *atchan)
352{
353 struct at_dma *atdma = to_at_dma(atchan->chan_common.device);
354
355 dev_err(chan2dev(&atchan->chan_common),
356 " channel %d : imr = 0x%x, chsr = 0x%x\n",
357 atchan->chan_common.chan_id,
358 dma_readl(atdma, EBCIMR),
359 dma_readl(atdma, CHSR));
360
361 dev_err(chan2dev(&atchan->chan_common),
Nicolas Ferre808347f2009-07-22 20:04:45 +0200362 " channel: s0x%x d0x%x ctrl0x%x:0x%x cfg0x%x l0x%x\n",
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200363 channel_readl(atchan, SADDR),
364 channel_readl(atchan, DADDR),
365 channel_readl(atchan, CTRLA),
366 channel_readl(atchan, CTRLB),
Nicolas Ferre808347f2009-07-22 20:04:45 +0200367 channel_readl(atchan, CFG),
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200368 channel_readl(atchan, DSCR));
369}
370#else
371static void vdbg_dump_regs(struct at_dma_chan *atchan) {}
372#endif
373
374static void atc_dump_lli(struct at_dma_chan *atchan, struct at_lli *lli)
375{
Joe Perches1ba151c2012-10-28 01:05:44 -0700376 dev_crit(chan2dev(&atchan->chan_common),
377 " desc: s0x%x d0x%x ctrl0x%x:0x%x l0x%x\n",
378 lli->saddr, lli->daddr,
379 lli->ctrla, lli->ctrlb, lli->dscr);
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200380}
381
382
Nikolaus Vossbda3a472012-01-17 10:28:33 +0100383static void atc_setup_irq(struct at_dma *atdma, int chan_id, int on)
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200384{
Nikolaus Vossbda3a472012-01-17 10:28:33 +0100385 u32 ebci;
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200386
Nicolas Ferre9b3aa582011-04-30 16:57:45 +0200387 /* enable interrupts on buffer transfer completion & error */
Nikolaus Vossbda3a472012-01-17 10:28:33 +0100388 ebci = AT_DMA_BTC(chan_id)
389 | AT_DMA_ERR(chan_id);
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200390 if (on)
391 dma_writel(atdma, EBCIER, ebci);
392 else
393 dma_writel(atdma, EBCIDR, ebci);
394}
395
Nikolaus Vossbda3a472012-01-17 10:28:33 +0100396static void atc_enable_chan_irq(struct at_dma *atdma, int chan_id)
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200397{
Nikolaus Vossbda3a472012-01-17 10:28:33 +0100398 atc_setup_irq(atdma, chan_id, 1);
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200399}
400
Nikolaus Vossbda3a472012-01-17 10:28:33 +0100401static void atc_disable_chan_irq(struct at_dma *atdma, int chan_id)
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200402{
Nikolaus Vossbda3a472012-01-17 10:28:33 +0100403 atc_setup_irq(atdma, chan_id, 0);
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200404}
405
406
407/**
408 * atc_chan_is_enabled - test if given channel is enabled
409 * @atchan: channel we want to test status
410 */
411static inline int atc_chan_is_enabled(struct at_dma_chan *atchan)
412{
413 struct at_dma *atdma = to_at_dma(atchan->chan_common.device);
414
415 return !!(dma_readl(atdma, CHSR) & atchan->mask);
416}
417
Nicolas Ferre3c477482011-07-25 21:09:23 +0000418/**
419 * atc_chan_is_paused - test channel pause/resume status
420 * @atchan: channel we want to test status
421 */
422static inline int atc_chan_is_paused(struct at_dma_chan *atchan)
423{
424 return test_bit(ATC_IS_PAUSED, &atchan->status);
425}
426
427/**
428 * atc_chan_is_cyclic - test if given channel has cyclic property set
429 * @atchan: channel we want to test status
430 */
431static inline int atc_chan_is_cyclic(struct at_dma_chan *atchan)
432{
433 return test_bit(ATC_IS_CYCLIC, &atchan->status);
434}
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200435
436/**
437 * set_desc_eol - set end-of-link to descriptor so it will end transfer
438 * @desc: descriptor, signle or at the end of a chain, to end chain on
439 */
440static void set_desc_eol(struct at_desc *desc)
441{
Nicolas Ferre9b3aa582011-04-30 16:57:45 +0200442 u32 ctrlb = desc->lli.ctrlb;
443
444 ctrlb &= ~ATC_IEN;
445 ctrlb |= ATC_SRC_DSCR_DIS | ATC_DST_DSCR_DIS;
446
447 desc->lli.ctrlb = ctrlb;
Nicolas Ferredc78baa2009-07-03 19:24:33 +0200448 desc->lli.dscr = 0;
449}
450
451#endif /* AT_HDMAC_REGS_H */