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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * au1550 psc spi controller driver
4 * may work also with au1200, au1210, au1250
5 * will not work on au1000, au1100 and au1500 (no full spi controller there)
6 *
7 * Copyright (c) 2006 ATRON electronic GmbH
8 * Author: Jan Nikitenko <jan.nikitenko@gmail.com>
9 */
10
11#include <linux/init.h>
12#include <linux/interrupt.h>
13#include <linux/slab.h>
14#include <linux/errno.h>
15#include <linux/module.h>
16#include <linux/device.h>
17#include <linux/platform_device.h>
18#include <linux/resource.h>
19#include <linux/spi/spi.h>
20#include <linux/spi/spi_bitbang.h>
21#include <linux/dma-mapping.h>
22#include <linux/completion.h>
23#include <asm/mach-au1x00/au1000.h>
24#include <asm/mach-au1x00/au1xxx_psc.h>
25#include <asm/mach-au1x00/au1xxx_dbdma.h>
26
27#include <asm/mach-au1x00/au1550_spi.h>
28
29static unsigned int usedma = 1;
30module_param(usedma, uint, 0644);
31
32/*
33#define AU1550_SPI_DEBUG_LOOPBACK
34*/
35
36
37#define AU1550_SPI_DBDMA_DESCRIPTORS 1
38#define AU1550_SPI_DMA_RXTMP_MINSIZE 2048U
39
40struct au1550_spi {
41 struct spi_bitbang bitbang;
42
43 volatile psc_spi_t __iomem *regs;
44 int irq;
45
46 unsigned int len;
47 unsigned int tx_count;
48 unsigned int rx_count;
49 const u8 *tx;
50 u8 *rx;
51
52 void (*rx_word)(struct au1550_spi *hw);
53 void (*tx_word)(struct au1550_spi *hw);
54 int (*txrx_bufs)(struct spi_device *spi, struct spi_transfer *t);
55 irqreturn_t (*irq_callback)(struct au1550_spi *hw);
56
57 struct completion host_done;
58
59 unsigned int usedma;
60 u32 dma_tx_id;
61 u32 dma_rx_id;
62 u32 dma_tx_ch;
63 u32 dma_rx_ch;
64
65 u8 *dma_rx_tmpbuf;
66 unsigned int dma_rx_tmpbuf_size;
67 u32 dma_rx_tmpbuf_addr;
68
69 struct spi_controller *host;
70 struct device *dev;
71 struct au1550_spi_info *pdata;
72 struct resource *ioarea;
73};
74
75
76/* we use an 8-bit memory device for dma transfers to/from spi fifo */
77static dbdev_tab_t au1550_spi_mem_dbdev = {
78 .dev_id = DBDMA_MEM_CHAN,
79 .dev_flags = DEV_FLAGS_ANYUSE|DEV_FLAGS_SYNC,
80 .dev_tsize = 0,
81 .dev_devwidth = 8,
82 .dev_physaddr = 0x00000000,
83 .dev_intlevel = 0,
84 .dev_intpolarity = 0
85};
86
87static int ddma_memid; /* id to above mem dma device */
88
89static void au1550_spi_bits_handlers_set(struct au1550_spi *hw, int bpw);
90
91
92/*
93 * compute BRG and DIV bits to setup spi clock based on main input clock rate
94 * that was specified in platform data structure
95 * according to au1550 datasheet:
96 * psc_tempclk = psc_mainclk / (2 << DIV)
97 * spiclk = psc_tempclk / (2 * (BRG + 1))
98 * BRG valid range is 4..63
99 * DIV valid range is 0..3
100 */
101static u32 au1550_spi_baudcfg(struct au1550_spi *hw, unsigned int speed_hz)
102{
103 u32 mainclk_hz = hw->pdata->mainclk_hz;
104 u32 div, brg;
105
106 for (div = 0; div < 4; div++) {
107 brg = mainclk_hz / speed_hz / (4 << div);
108 /* now we have BRG+1 in brg, so count with that */
109 if (brg < (4 + 1)) {
110 brg = (4 + 1); /* speed_hz too big */
111 break; /* set lowest brg (div is == 0) */
112 }
113 if (brg <= (63 + 1))
114 break; /* we have valid brg and div */
115 }
116 if (div == 4) {
117 div = 3; /* speed_hz too small */
118 brg = (63 + 1); /* set highest brg and div */
119 }
120 brg--;
121 return PSC_SPICFG_SET_BAUD(brg) | PSC_SPICFG_SET_DIV(div);
122}
123
124static inline void au1550_spi_mask_ack_all(struct au1550_spi *hw)
125{
126 hw->regs->psc_spimsk =
127 PSC_SPIMSK_MM | PSC_SPIMSK_RR | PSC_SPIMSK_RO
128 | PSC_SPIMSK_RU | PSC_SPIMSK_TR | PSC_SPIMSK_TO
129 | PSC_SPIMSK_TU | PSC_SPIMSK_SD | PSC_SPIMSK_MD;
130 wmb(); /* drain writebuffer */
131
132 hw->regs->psc_spievent =
133 PSC_SPIEVNT_MM | PSC_SPIEVNT_RR | PSC_SPIEVNT_RO
134 | PSC_SPIEVNT_RU | PSC_SPIEVNT_TR | PSC_SPIEVNT_TO
135 | PSC_SPIEVNT_TU | PSC_SPIEVNT_SD | PSC_SPIEVNT_MD;
136 wmb(); /* drain writebuffer */
137}
138
139static void au1550_spi_reset_fifos(struct au1550_spi *hw)
140{
141 u32 pcr;
142
143 hw->regs->psc_spipcr = PSC_SPIPCR_RC | PSC_SPIPCR_TC;
144 wmb(); /* drain writebuffer */
145 do {
146 pcr = hw->regs->psc_spipcr;
147 wmb(); /* drain writebuffer */
148 } while (pcr != 0);
149}
150
151/*
152 * dma transfers are used for the most common spi word size of 8-bits
153 * we cannot easily change already set up dma channels' width, so if we wanted
154 * dma support for more than 8-bit words (up to 24 bits), we would need to
155 * setup dma channels from scratch on each spi transfer, based on bits_per_word
156 * instead we have pre set up 8 bit dma channels supporting spi 4 to 8 bits
157 * transfers, and 9 to 24 bits spi transfers will be done in pio irq based mode
158 * callbacks to handle dma or pio are set up in au1550_spi_bits_handlers_set()
159 */
160static void au1550_spi_chipsel(struct spi_device *spi, int value)
161{
162 struct au1550_spi *hw = spi_controller_get_devdata(spi->controller);
163 unsigned int cspol = spi->mode & SPI_CS_HIGH ? 1 : 0;
164 u32 cfg, stat;
165
166 switch (value) {
167 case BITBANG_CS_INACTIVE:
168 if (hw->pdata->deactivate_cs)
169 hw->pdata->deactivate_cs(hw->pdata, spi_get_chipselect(spi, 0),
170 cspol);
171 break;
172
173 case BITBANG_CS_ACTIVE:
174 au1550_spi_bits_handlers_set(hw, spi->bits_per_word);
175
176 cfg = hw->regs->psc_spicfg;
177 wmb(); /* drain writebuffer */
178 hw->regs->psc_spicfg = cfg & ~PSC_SPICFG_DE_ENABLE;
179 wmb(); /* drain writebuffer */
180
181 if (spi->mode & SPI_CPOL)
182 cfg |= PSC_SPICFG_BI;
183 else
184 cfg &= ~PSC_SPICFG_BI;
185 if (spi->mode & SPI_CPHA)
186 cfg &= ~PSC_SPICFG_CDE;
187 else
188 cfg |= PSC_SPICFG_CDE;
189
190 if (spi->mode & SPI_LSB_FIRST)
191 cfg |= PSC_SPICFG_MLF;
192 else
193 cfg &= ~PSC_SPICFG_MLF;
194
195 if (hw->usedma && spi->bits_per_word <= 8)
196 cfg &= ~PSC_SPICFG_DD_DISABLE;
197 else
198 cfg |= PSC_SPICFG_DD_DISABLE;
199 cfg = PSC_SPICFG_CLR_LEN(cfg);
200 cfg |= PSC_SPICFG_SET_LEN(spi->bits_per_word);
201
202 cfg = PSC_SPICFG_CLR_BAUD(cfg);
203 cfg &= ~PSC_SPICFG_SET_DIV(3);
204 cfg |= au1550_spi_baudcfg(hw, spi->max_speed_hz);
205
206 hw->regs->psc_spicfg = cfg | PSC_SPICFG_DE_ENABLE;
207 wmb(); /* drain writebuffer */
208 do {
209 stat = hw->regs->psc_spistat;
210 wmb(); /* drain writebuffer */
211 } while ((stat & PSC_SPISTAT_DR) == 0);
212
213 if (hw->pdata->activate_cs)
214 hw->pdata->activate_cs(hw->pdata, spi_get_chipselect(spi, 0),
215 cspol);
216 break;
217 }
218}
219
220static int au1550_spi_setupxfer(struct spi_device *spi, struct spi_transfer *t)
221{
222 struct au1550_spi *hw = spi_controller_get_devdata(spi->controller);
223 unsigned int bpw, hz;
224 u32 cfg, stat;
225
226 if (t) {
227 bpw = t->bits_per_word;
228 hz = t->speed_hz;
229 } else {
230 bpw = spi->bits_per_word;
231 hz = spi->max_speed_hz;
232 }
233
234 if (!hz)
235 return -EINVAL;
236
237 au1550_spi_bits_handlers_set(hw, spi->bits_per_word);
238
239 cfg = hw->regs->psc_spicfg;
240 wmb(); /* drain writebuffer */
241 hw->regs->psc_spicfg = cfg & ~PSC_SPICFG_DE_ENABLE;
242 wmb(); /* drain writebuffer */
243
244 if (hw->usedma && bpw <= 8)
245 cfg &= ~PSC_SPICFG_DD_DISABLE;
246 else
247 cfg |= PSC_SPICFG_DD_DISABLE;
248 cfg = PSC_SPICFG_CLR_LEN(cfg);
249 cfg |= PSC_SPICFG_SET_LEN(bpw);
250
251 cfg = PSC_SPICFG_CLR_BAUD(cfg);
252 cfg &= ~PSC_SPICFG_SET_DIV(3);
253 cfg |= au1550_spi_baudcfg(hw, hz);
254
255 hw->regs->psc_spicfg = cfg;
256 wmb(); /* drain writebuffer */
257
258 if (cfg & PSC_SPICFG_DE_ENABLE) {
259 do {
260 stat = hw->regs->psc_spistat;
261 wmb(); /* drain writebuffer */
262 } while ((stat & PSC_SPISTAT_DR) == 0);
263 }
264
265 au1550_spi_reset_fifos(hw);
266 au1550_spi_mask_ack_all(hw);
267 return 0;
268}
269
270/*
271 * for dma spi transfers, we have to setup rx channel, otherwise there is
272 * no reliable way how to recognize that spi transfer is done
273 * dma complete callbacks are called before real spi transfer is finished
274 * and if only tx dma channel is set up (and rx fifo overflow event masked)
275 * spi host done event irq is not generated unless rx fifo is empty (emptied)
276 * so we need rx tmp buffer to use for rx dma if user does not provide one
277 */
278static int au1550_spi_dma_rxtmp_alloc(struct au1550_spi *hw, unsigned int size)
279{
280 hw->dma_rx_tmpbuf = kmalloc(size, GFP_KERNEL);
281 if (!hw->dma_rx_tmpbuf)
282 return -ENOMEM;
283 hw->dma_rx_tmpbuf_size = size;
284 hw->dma_rx_tmpbuf_addr = dma_map_single(hw->dev, hw->dma_rx_tmpbuf,
285 size, DMA_FROM_DEVICE);
286 if (dma_mapping_error(hw->dev, hw->dma_rx_tmpbuf_addr)) {
287 kfree(hw->dma_rx_tmpbuf);
288 hw->dma_rx_tmpbuf = 0;
289 hw->dma_rx_tmpbuf_size = 0;
290 return -EFAULT;
291 }
292 return 0;
293}
294
295static void au1550_spi_dma_rxtmp_free(struct au1550_spi *hw)
296{
297 dma_unmap_single(hw->dev, hw->dma_rx_tmpbuf_addr,
298 hw->dma_rx_tmpbuf_size, DMA_FROM_DEVICE);
299 kfree(hw->dma_rx_tmpbuf);
300 hw->dma_rx_tmpbuf = 0;
301 hw->dma_rx_tmpbuf_size = 0;
302}
303
304static int au1550_spi_dma_txrxb(struct spi_device *spi, struct spi_transfer *t)
305{
306 struct au1550_spi *hw = spi_controller_get_devdata(spi->controller);
307 dma_addr_t dma_tx_addr;
308 dma_addr_t dma_rx_addr;
309 u32 res;
310
311 hw->len = t->len;
312 hw->tx_count = 0;
313 hw->rx_count = 0;
314
315 hw->tx = t->tx_buf;
316 hw->rx = t->rx_buf;
317
318 /*
319 * - first map the TX buffer, so cache data gets written to memory
320 * - then map the RX buffer, so that cache entries (with
321 * soon-to-be-stale data) get removed
322 * use rx buffer in place of tx if tx buffer was not provided
323 * use temp rx buffer (preallocated or realloc to fit) for rx dma
324 */
325 if (t->tx_buf) {
326 dma_tx_addr = dma_map_single(hw->dev, (void *)t->tx_buf,
327 t->len, DMA_TO_DEVICE);
328 if (dma_mapping_error(hw->dev, dma_tx_addr))
329 dev_err(hw->dev, "tx dma map error\n");
330 }
331
332 if (t->rx_buf) {
333 dma_rx_addr = dma_map_single(hw->dev, (void *)t->rx_buf,
334 t->len, DMA_FROM_DEVICE);
335 if (dma_mapping_error(hw->dev, dma_rx_addr))
336 dev_err(hw->dev, "rx dma map error\n");
337 } else {
338 if (t->len > hw->dma_rx_tmpbuf_size) {
339 int ret;
340
341 au1550_spi_dma_rxtmp_free(hw);
342 ret = au1550_spi_dma_rxtmp_alloc(hw, max(t->len,
343 AU1550_SPI_DMA_RXTMP_MINSIZE));
344 if (ret < 0)
345 return ret;
346 }
347 hw->rx = hw->dma_rx_tmpbuf;
348 dma_rx_addr = hw->dma_rx_tmpbuf_addr;
349 dma_sync_single_for_device(hw->dev, dma_rx_addr,
350 t->len, DMA_FROM_DEVICE);
351 }
352
353 if (!t->tx_buf) {
354 dma_sync_single_for_device(hw->dev, dma_rx_addr,
355 t->len, DMA_BIDIRECTIONAL);
356 hw->tx = hw->rx;
357 }
358
359 /* put buffers on the ring */
360 res = au1xxx_dbdma_put_dest(hw->dma_rx_ch, virt_to_phys(hw->rx),
361 t->len, DDMA_FLAGS_IE);
362 if (!res)
363 dev_err(hw->dev, "rx dma put dest error\n");
364
365 res = au1xxx_dbdma_put_source(hw->dma_tx_ch, virt_to_phys(hw->tx),
366 t->len, DDMA_FLAGS_IE);
367 if (!res)
368 dev_err(hw->dev, "tx dma put source error\n");
369
370 au1xxx_dbdma_start(hw->dma_rx_ch);
371 au1xxx_dbdma_start(hw->dma_tx_ch);
372
373 /* by default enable nearly all events interrupt */
374 hw->regs->psc_spimsk = PSC_SPIMSK_SD;
375 wmb(); /* drain writebuffer */
376
377 /* start the transfer */
378 hw->regs->psc_spipcr = PSC_SPIPCR_MS;
379 wmb(); /* drain writebuffer */
380
381 wait_for_completion(&hw->host_done);
382
383 au1xxx_dbdma_stop(hw->dma_tx_ch);
384 au1xxx_dbdma_stop(hw->dma_rx_ch);
385
386 if (!t->rx_buf) {
387 /* using the temporal preallocated and premapped buffer */
388 dma_sync_single_for_cpu(hw->dev, dma_rx_addr, t->len,
389 DMA_FROM_DEVICE);
390 }
391 /* unmap buffers if mapped above */
392 if (t->rx_buf)
393 dma_unmap_single(hw->dev, dma_rx_addr, t->len,
394 DMA_FROM_DEVICE);
395 if (t->tx_buf)
396 dma_unmap_single(hw->dev, dma_tx_addr, t->len,
397 DMA_TO_DEVICE);
398
399 return min(hw->rx_count, hw->tx_count);
400}
401
402static irqreturn_t au1550_spi_dma_irq_callback(struct au1550_spi *hw)
403{
404 u32 stat, evnt;
405
406 stat = hw->regs->psc_spistat;
407 evnt = hw->regs->psc_spievent;
408 wmb(); /* drain writebuffer */
409 if ((stat & PSC_SPISTAT_DI) == 0) {
410 dev_err(hw->dev, "Unexpected IRQ!\n");
411 return IRQ_NONE;
412 }
413
414 if ((evnt & (PSC_SPIEVNT_MM | PSC_SPIEVNT_RO
415 | PSC_SPIEVNT_RU | PSC_SPIEVNT_TO
416 | PSC_SPIEVNT_TU | PSC_SPIEVNT_SD))
417 != 0) {
418 /*
419 * due to an spi error we consider transfer as done,
420 * so mask all events until before next transfer start
421 * and stop the possibly running dma immediately
422 */
423 au1550_spi_mask_ack_all(hw);
424 au1xxx_dbdma_stop(hw->dma_rx_ch);
425 au1xxx_dbdma_stop(hw->dma_tx_ch);
426
427 /* get number of transferred bytes */
428 hw->rx_count = hw->len - au1xxx_get_dma_residue(hw->dma_rx_ch);
429 hw->tx_count = hw->len - au1xxx_get_dma_residue(hw->dma_tx_ch);
430
431 au1xxx_dbdma_reset(hw->dma_rx_ch);
432 au1xxx_dbdma_reset(hw->dma_tx_ch);
433 au1550_spi_reset_fifos(hw);
434
435 if (evnt == PSC_SPIEVNT_RO)
436 dev_err(hw->dev,
437 "dma transfer: receive FIFO overflow!\n");
438 else
439 dev_err(hw->dev,
440 "dma transfer: unexpected SPI error (event=0x%x stat=0x%x)!\n",
441 evnt, stat);
442
443 complete(&hw->host_done);
444 return IRQ_HANDLED;
445 }
446
447 if ((evnt & PSC_SPIEVNT_MD) != 0) {
448 /* transfer completed successfully */
449 au1550_spi_mask_ack_all(hw);
450 hw->rx_count = hw->len;
451 hw->tx_count = hw->len;
452 complete(&hw->host_done);
453 }
454 return IRQ_HANDLED;
455}
456
457
458/* routines to handle different word sizes in pio mode */
459#define AU1550_SPI_RX_WORD(size, mask) \
460static void au1550_spi_rx_word_##size(struct au1550_spi *hw) \
461{ \
462 u32 fifoword = hw->regs->psc_spitxrx & (u32)(mask); \
463 wmb(); /* drain writebuffer */ \
464 if (hw->rx) { \
465 *(u##size *)hw->rx = (u##size)fifoword; \
466 hw->rx += (size) / 8; \
467 } \
468 hw->rx_count += (size) / 8; \
469}
470
471#define AU1550_SPI_TX_WORD(size, mask) \
472static void au1550_spi_tx_word_##size(struct au1550_spi *hw) \
473{ \
474 u32 fifoword = 0; \
475 if (hw->tx) { \
476 fifoword = *(u##size *)hw->tx & (u32)(mask); \
477 hw->tx += (size) / 8; \
478 } \
479 hw->tx_count += (size) / 8; \
480 if (hw->tx_count >= hw->len) \
481 fifoword |= PSC_SPITXRX_LC; \
482 hw->regs->psc_spitxrx = fifoword; \
483 wmb(); /* drain writebuffer */ \
484}
485
486AU1550_SPI_RX_WORD(8, 0xff)
487AU1550_SPI_RX_WORD(16, 0xffff)
488AU1550_SPI_RX_WORD(32, 0xffffff)
489AU1550_SPI_TX_WORD(8, 0xff)
490AU1550_SPI_TX_WORD(16, 0xffff)
491AU1550_SPI_TX_WORD(32, 0xffffff)
492
493static int au1550_spi_pio_txrxb(struct spi_device *spi, struct spi_transfer *t)
494{
495 u32 stat, mask;
496 struct au1550_spi *hw = spi_controller_get_devdata(spi->controller);
497
498 hw->tx = t->tx_buf;
499 hw->rx = t->rx_buf;
500 hw->len = t->len;
501 hw->tx_count = 0;
502 hw->rx_count = 0;
503
504 /* by default enable nearly all events after filling tx fifo */
505 mask = PSC_SPIMSK_SD;
506
507 /* fill the transmit FIFO */
508 while (hw->tx_count < hw->len) {
509
510 hw->tx_word(hw);
511
512 if (hw->tx_count >= hw->len) {
513 /* mask tx fifo request interrupt as we are done */
514 mask |= PSC_SPIMSK_TR;
515 }
516
517 stat = hw->regs->psc_spistat;
518 wmb(); /* drain writebuffer */
519 if (stat & PSC_SPISTAT_TF)
520 break;
521 }
522
523 /* enable event interrupts */
524 hw->regs->psc_spimsk = mask;
525 wmb(); /* drain writebuffer */
526
527 /* start the transfer */
528 hw->regs->psc_spipcr = PSC_SPIPCR_MS;
529 wmb(); /* drain writebuffer */
530
531 wait_for_completion(&hw->host_done);
532
533 return min(hw->rx_count, hw->tx_count);
534}
535
536static irqreturn_t au1550_spi_pio_irq_callback(struct au1550_spi *hw)
537{
538 int busy;
539 u32 stat, evnt;
540
541 stat = hw->regs->psc_spistat;
542 evnt = hw->regs->psc_spievent;
543 wmb(); /* drain writebuffer */
544 if ((stat & PSC_SPISTAT_DI) == 0) {
545 dev_err(hw->dev, "Unexpected IRQ!\n");
546 return IRQ_NONE;
547 }
548
549 if ((evnt & (PSC_SPIEVNT_MM | PSC_SPIEVNT_RO
550 | PSC_SPIEVNT_RU | PSC_SPIEVNT_TO
551 | PSC_SPIEVNT_SD))
552 != 0) {
553 /*
554 * due to an error we consider transfer as done,
555 * so mask all events until before next transfer start
556 */
557 au1550_spi_mask_ack_all(hw);
558 au1550_spi_reset_fifos(hw);
559 dev_err(hw->dev,
560 "pio transfer: unexpected SPI error (event=0x%x stat=0x%x)!\n",
561 evnt, stat);
562 complete(&hw->host_done);
563 return IRQ_HANDLED;
564 }
565
566 /*
567 * while there is something to read from rx fifo
568 * or there is a space to write to tx fifo:
569 */
570 do {
571 busy = 0;
572 stat = hw->regs->psc_spistat;
573 wmb(); /* drain writebuffer */
574
575 /*
576 * Take care to not let the Rx FIFO overflow.
577 *
578 * We only write a byte if we have read one at least. Initially,
579 * the write fifo is full, so we should read from the read fifo
580 * first.
581 * In case we miss a word from the read fifo, we should get a
582 * RO event and should back out.
583 */
584 if (!(stat & PSC_SPISTAT_RE) && hw->rx_count < hw->len) {
585 hw->rx_word(hw);
586 busy = 1;
587
588 if (!(stat & PSC_SPISTAT_TF) && hw->tx_count < hw->len)
589 hw->tx_word(hw);
590 }
591 } while (busy);
592
593 hw->regs->psc_spievent = PSC_SPIEVNT_RR | PSC_SPIEVNT_TR;
594 wmb(); /* drain writebuffer */
595
596 /*
597 * Restart the SPI transmission in case of a transmit underflow.
598 * This seems to work despite the notes in the Au1550 data book
599 * of Figure 8-4 with flowchart for SPI host operation:
600 *
601 * """Note 1: An XFR Error Interrupt occurs, unless masked,
602 * for any of the following events: Tx FIFO Underflow,
603 * Rx FIFO Overflow, or Multiple-host Error
604 * Note 2: In case of a Tx Underflow Error, all zeroes are
605 * transmitted."""
606 *
607 * By simply restarting the spi transfer on Tx Underflow Error,
608 * we assume that spi transfer was paused instead of zeroes
609 * transmittion mentioned in the Note 2 of Au1550 data book.
610 */
611 if (evnt & PSC_SPIEVNT_TU) {
612 hw->regs->psc_spievent = PSC_SPIEVNT_TU | PSC_SPIEVNT_MD;
613 wmb(); /* drain writebuffer */
614 hw->regs->psc_spipcr = PSC_SPIPCR_MS;
615 wmb(); /* drain writebuffer */
616 }
617
618 if (hw->rx_count >= hw->len) {
619 /* transfer completed successfully */
620 au1550_spi_mask_ack_all(hw);
621 complete(&hw->host_done);
622 }
623 return IRQ_HANDLED;
624}
625
626static int au1550_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
627{
628 struct au1550_spi *hw = spi_controller_get_devdata(spi->controller);
629
630 return hw->txrx_bufs(spi, t);
631}
632
633static irqreturn_t au1550_spi_irq(int irq, void *dev)
634{
635 struct au1550_spi *hw = dev;
636
637 return hw->irq_callback(hw);
638}
639
640static void au1550_spi_bits_handlers_set(struct au1550_spi *hw, int bpw)
641{
642 if (bpw <= 8) {
643 if (hw->usedma) {
644 hw->txrx_bufs = &au1550_spi_dma_txrxb;
645 hw->irq_callback = &au1550_spi_dma_irq_callback;
646 } else {
647 hw->rx_word = &au1550_spi_rx_word_8;
648 hw->tx_word = &au1550_spi_tx_word_8;
649 hw->txrx_bufs = &au1550_spi_pio_txrxb;
650 hw->irq_callback = &au1550_spi_pio_irq_callback;
651 }
652 } else if (bpw <= 16) {
653 hw->rx_word = &au1550_spi_rx_word_16;
654 hw->tx_word = &au1550_spi_tx_word_16;
655 hw->txrx_bufs = &au1550_spi_pio_txrxb;
656 hw->irq_callback = &au1550_spi_pio_irq_callback;
657 } else {
658 hw->rx_word = &au1550_spi_rx_word_32;
659 hw->tx_word = &au1550_spi_tx_word_32;
660 hw->txrx_bufs = &au1550_spi_pio_txrxb;
661 hw->irq_callback = &au1550_spi_pio_irq_callback;
662 }
663}
664
665static void au1550_spi_setup_psc_as_spi(struct au1550_spi *hw)
666{
667 u32 stat, cfg;
668
669 /* set up the PSC for SPI mode */
670 hw->regs->psc_ctrl = PSC_CTRL_DISABLE;
671 wmb(); /* drain writebuffer */
672 hw->regs->psc_sel = PSC_SEL_PS_SPIMODE;
673 wmb(); /* drain writebuffer */
674
675 hw->regs->psc_spicfg = 0;
676 wmb(); /* drain writebuffer */
677
678 hw->regs->psc_ctrl = PSC_CTRL_ENABLE;
679 wmb(); /* drain writebuffer */
680
681 do {
682 stat = hw->regs->psc_spistat;
683 wmb(); /* drain writebuffer */
684 } while ((stat & PSC_SPISTAT_SR) == 0);
685
686
687 cfg = hw->usedma ? 0 : PSC_SPICFG_DD_DISABLE;
688 cfg |= PSC_SPICFG_SET_LEN(8);
689 cfg |= PSC_SPICFG_RT_FIFO8 | PSC_SPICFG_TT_FIFO8;
690 /* use minimal allowed brg and div values as initial setting: */
691 cfg |= PSC_SPICFG_SET_BAUD(4) | PSC_SPICFG_SET_DIV(0);
692
693#ifdef AU1550_SPI_DEBUG_LOOPBACK
694 cfg |= PSC_SPICFG_LB;
695#endif
696
697 hw->regs->psc_spicfg = cfg;
698 wmb(); /* drain writebuffer */
699
700 au1550_spi_mask_ack_all(hw);
701
702 hw->regs->psc_spicfg |= PSC_SPICFG_DE_ENABLE;
703 wmb(); /* drain writebuffer */
704
705 do {
706 stat = hw->regs->psc_spistat;
707 wmb(); /* drain writebuffer */
708 } while ((stat & PSC_SPISTAT_DR) == 0);
709
710 au1550_spi_reset_fifos(hw);
711}
712
713
714static int au1550_spi_probe(struct platform_device *pdev)
715{
716 struct au1550_spi *hw;
717 struct spi_controller *host;
718 struct resource *r;
719 int err = 0;
720
721 host = spi_alloc_host(&pdev->dev, sizeof(struct au1550_spi));
722 if (host == NULL) {
723 dev_err(&pdev->dev, "No memory for spi_controller\n");
724 err = -ENOMEM;
725 goto err_nomem;
726 }
727
728 /* the spi->mode bits understood by this driver: */
729 host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
730 host->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 24);
731
732 hw = spi_controller_get_devdata(host);
733
734 hw->host = host;
735 hw->pdata = dev_get_platdata(&pdev->dev);
736 hw->dev = &pdev->dev;
737
738 if (hw->pdata == NULL) {
739 dev_err(&pdev->dev, "No platform data supplied\n");
740 err = -ENOENT;
741 goto err_no_pdata;
742 }
743
744 r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
745 if (!r) {
746 dev_err(&pdev->dev, "no IRQ\n");
747 err = -ENODEV;
748 goto err_no_iores;
749 }
750 hw->irq = r->start;
751
752 hw->usedma = 0;
753 r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
754 if (r) {
755 hw->dma_tx_id = r->start;
756 r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
757 if (r) {
758 hw->dma_rx_id = r->start;
759 if (usedma && ddma_memid) {
760 if (pdev->dev.dma_mask == NULL)
761 dev_warn(&pdev->dev, "no dma mask\n");
762 else
763 hw->usedma = 1;
764 }
765 }
766 }
767
768 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
769 if (!r) {
770 dev_err(&pdev->dev, "no mmio resource\n");
771 err = -ENODEV;
772 goto err_no_iores;
773 }
774
775 hw->ioarea = request_mem_region(r->start, sizeof(psc_spi_t),
776 pdev->name);
777 if (!hw->ioarea) {
778 dev_err(&pdev->dev, "Cannot reserve iomem region\n");
779 err = -ENXIO;
780 goto err_no_iores;
781 }
782
783 hw->regs = (psc_spi_t __iomem *)ioremap(r->start, sizeof(psc_spi_t));
784 if (!hw->regs) {
785 dev_err(&pdev->dev, "cannot ioremap\n");
786 err = -ENXIO;
787 goto err_ioremap;
788 }
789
790 platform_set_drvdata(pdev, hw);
791
792 init_completion(&hw->host_done);
793
794 hw->bitbang.ctlr = hw->host;
795 hw->bitbang.setup_transfer = au1550_spi_setupxfer;
796 hw->bitbang.chipselect = au1550_spi_chipsel;
797 hw->bitbang.txrx_bufs = au1550_spi_txrx_bufs;
798
799 if (hw->usedma) {
800 hw->dma_tx_ch = au1xxx_dbdma_chan_alloc(ddma_memid,
801 hw->dma_tx_id, NULL, (void *)hw);
802 if (hw->dma_tx_ch == 0) {
803 dev_err(&pdev->dev,
804 "Cannot allocate tx dma channel\n");
805 err = -ENXIO;
806 goto err_no_txdma;
807 }
808 au1xxx_dbdma_set_devwidth(hw->dma_tx_ch, 8);
809 if (au1xxx_dbdma_ring_alloc(hw->dma_tx_ch,
810 AU1550_SPI_DBDMA_DESCRIPTORS) == 0) {
811 dev_err(&pdev->dev,
812 "Cannot allocate tx dma descriptors\n");
813 err = -ENXIO;
814 goto err_no_txdma_descr;
815 }
816
817
818 hw->dma_rx_ch = au1xxx_dbdma_chan_alloc(hw->dma_rx_id,
819 ddma_memid, NULL, (void *)hw);
820 if (hw->dma_rx_ch == 0) {
821 dev_err(&pdev->dev,
822 "Cannot allocate rx dma channel\n");
823 err = -ENXIO;
824 goto err_no_rxdma;
825 }
826 au1xxx_dbdma_set_devwidth(hw->dma_rx_ch, 8);
827 if (au1xxx_dbdma_ring_alloc(hw->dma_rx_ch,
828 AU1550_SPI_DBDMA_DESCRIPTORS) == 0) {
829 dev_err(&pdev->dev,
830 "Cannot allocate rx dma descriptors\n");
831 err = -ENXIO;
832 goto err_no_rxdma_descr;
833 }
834
835 err = au1550_spi_dma_rxtmp_alloc(hw,
836 AU1550_SPI_DMA_RXTMP_MINSIZE);
837 if (err < 0) {
838 dev_err(&pdev->dev,
839 "Cannot allocate initial rx dma tmp buffer\n");
840 goto err_dma_rxtmp_alloc;
841 }
842 }
843
844 au1550_spi_bits_handlers_set(hw, 8);
845
846 err = request_irq(hw->irq, au1550_spi_irq, 0, pdev->name, hw);
847 if (err) {
848 dev_err(&pdev->dev, "Cannot claim IRQ\n");
849 goto err_no_irq;
850 }
851
852 host->bus_num = pdev->id;
853 host->num_chipselect = hw->pdata->num_chipselect;
854
855 /*
856 * precompute valid range for spi freq - from au1550 datasheet:
857 * psc_tempclk = psc_mainclk / (2 << DIV)
858 * spiclk = psc_tempclk / (2 * (BRG + 1))
859 * BRG valid range is 4..63
860 * DIV valid range is 0..3
861 * round the min and max frequencies to values that would still
862 * produce valid brg and div
863 */
864 {
865 int min_div = (2 << 0) * (2 * (4 + 1));
866 int max_div = (2 << 3) * (2 * (63 + 1));
867
868 host->max_speed_hz = hw->pdata->mainclk_hz / min_div;
869 host->min_speed_hz =
870 hw->pdata->mainclk_hz / (max_div + 1) + 1;
871 }
872
873 au1550_spi_setup_psc_as_spi(hw);
874
875 err = spi_bitbang_start(&hw->bitbang);
876 if (err) {
877 dev_err(&pdev->dev, "Failed to register SPI host\n");
878 goto err_register;
879 }
880
881 dev_info(&pdev->dev,
882 "spi host registered: bus_num=%d num_chipselect=%d\n",
883 host->bus_num, host->num_chipselect);
884
885 return 0;
886
887err_register:
888 free_irq(hw->irq, hw);
889
890err_no_irq:
891 au1550_spi_dma_rxtmp_free(hw);
892
893err_dma_rxtmp_alloc:
894err_no_rxdma_descr:
895 if (hw->usedma)
896 au1xxx_dbdma_chan_free(hw->dma_rx_ch);
897
898err_no_rxdma:
899err_no_txdma_descr:
900 if (hw->usedma)
901 au1xxx_dbdma_chan_free(hw->dma_tx_ch);
902
903err_no_txdma:
904 iounmap((void __iomem *)hw->regs);
905
906err_ioremap:
907 release_mem_region(r->start, sizeof(psc_spi_t));
908
909err_no_iores:
910err_no_pdata:
911 spi_controller_put(hw->host);
912
913err_nomem:
914 return err;
915}
916
917static void au1550_spi_remove(struct platform_device *pdev)
918{
919 struct au1550_spi *hw = platform_get_drvdata(pdev);
920
921 dev_info(&pdev->dev, "spi host remove: bus_num=%d\n",
922 hw->host->bus_num);
923
924 spi_bitbang_stop(&hw->bitbang);
925 free_irq(hw->irq, hw);
926 iounmap((void __iomem *)hw->regs);
927 release_mem_region(hw->ioarea->start, sizeof(psc_spi_t));
928
929 if (hw->usedma) {
930 au1550_spi_dma_rxtmp_free(hw);
931 au1xxx_dbdma_chan_free(hw->dma_rx_ch);
932 au1xxx_dbdma_chan_free(hw->dma_tx_ch);
933 }
934
935 spi_controller_put(hw->host);
936}
937
938/* work with hotplug and coldplug */
939MODULE_ALIAS("platform:au1550-spi");
940
941static struct platform_driver au1550_spi_drv = {
942 .probe = au1550_spi_probe,
943 .remove = au1550_spi_remove,
944 .driver = {
945 .name = "au1550-spi",
946 },
947};
948
949static int __init au1550_spi_init(void)
950{
951 /*
952 * create memory device with 8 bits dev_devwidth
953 * needed for proper byte ordering to spi fifo
954 */
955 switch (alchemy_get_cputype()) {
956 case ALCHEMY_CPU_AU1550:
957 case ALCHEMY_CPU_AU1200:
958 case ALCHEMY_CPU_AU1300:
959 break;
960 default:
961 return -ENODEV;
962 }
963
964 if (usedma) {
965 ddma_memid = au1xxx_ddma_add_device(&au1550_spi_mem_dbdev);
966 if (!ddma_memid)
967 printk(KERN_ERR "au1550-spi: cannot add memory dbdma device\n");
968 }
969 return platform_driver_register(&au1550_spi_drv);
970}
971module_init(au1550_spi_init);
972
973static void __exit au1550_spi_exit(void)
974{
975 if (usedma && ddma_memid)
976 au1xxx_ddma_del_device(ddma_memid);
977 platform_driver_unregister(&au1550_spi_drv);
978}
979module_exit(au1550_spi_exit);
980
981MODULE_DESCRIPTION("Au1550 PSC SPI Driver");
982MODULE_AUTHOR("Jan Nikitenko <jan.nikitenko@gmail.com>");
983MODULE_LICENSE("GPL");
1/*
2 * au1550 psc spi controller driver
3 * may work also with au1200, au1210, au1250
4 * will not work on au1000, au1100 and au1500 (no full spi controller there)
5 *
6 * Copyright (c) 2006 ATRON electronic GmbH
7 * Author: Jan Nikitenko <jan.nikitenko@gmail.com>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 */
23
24#include <linux/init.h>
25#include <linux/interrupt.h>
26#include <linux/slab.h>
27#include <linux/errno.h>
28#include <linux/module.h>
29#include <linux/device.h>
30#include <linux/platform_device.h>
31#include <linux/resource.h>
32#include <linux/spi/spi.h>
33#include <linux/spi/spi_bitbang.h>
34#include <linux/dma-mapping.h>
35#include <linux/completion.h>
36#include <asm/mach-au1x00/au1000.h>
37#include <asm/mach-au1x00/au1xxx_psc.h>
38#include <asm/mach-au1x00/au1xxx_dbdma.h>
39
40#include <asm/mach-au1x00/au1550_spi.h>
41
42static unsigned usedma = 1;
43module_param(usedma, uint, 0644);
44
45/*
46#define AU1550_SPI_DEBUG_LOOPBACK
47*/
48
49
50#define AU1550_SPI_DBDMA_DESCRIPTORS 1
51#define AU1550_SPI_DMA_RXTMP_MINSIZE 2048U
52
53struct au1550_spi {
54 struct spi_bitbang bitbang;
55
56 volatile psc_spi_t __iomem *regs;
57 int irq;
58
59 unsigned len;
60 unsigned tx_count;
61 unsigned rx_count;
62 const u8 *tx;
63 u8 *rx;
64
65 void (*rx_word)(struct au1550_spi *hw);
66 void (*tx_word)(struct au1550_spi *hw);
67 int (*txrx_bufs)(struct spi_device *spi, struct spi_transfer *t);
68 irqreturn_t (*irq_callback)(struct au1550_spi *hw);
69
70 struct completion master_done;
71
72 unsigned usedma;
73 u32 dma_tx_id;
74 u32 dma_rx_id;
75 u32 dma_tx_ch;
76 u32 dma_rx_ch;
77
78 u8 *dma_rx_tmpbuf;
79 unsigned dma_rx_tmpbuf_size;
80 u32 dma_rx_tmpbuf_addr;
81
82 struct spi_master *master;
83 struct device *dev;
84 struct au1550_spi_info *pdata;
85 struct resource *ioarea;
86};
87
88
89/* we use an 8-bit memory device for dma transfers to/from spi fifo */
90static dbdev_tab_t au1550_spi_mem_dbdev =
91{
92 .dev_id = DBDMA_MEM_CHAN,
93 .dev_flags = DEV_FLAGS_ANYUSE|DEV_FLAGS_SYNC,
94 .dev_tsize = 0,
95 .dev_devwidth = 8,
96 .dev_physaddr = 0x00000000,
97 .dev_intlevel = 0,
98 .dev_intpolarity = 0
99};
100
101static int ddma_memid; /* id to above mem dma device */
102
103static void au1550_spi_bits_handlers_set(struct au1550_spi *hw, int bpw);
104
105
106/*
107 * compute BRG and DIV bits to setup spi clock based on main input clock rate
108 * that was specified in platform data structure
109 * according to au1550 datasheet:
110 * psc_tempclk = psc_mainclk / (2 << DIV)
111 * spiclk = psc_tempclk / (2 * (BRG + 1))
112 * BRG valid range is 4..63
113 * DIV valid range is 0..3
114 */
115static u32 au1550_spi_baudcfg(struct au1550_spi *hw, unsigned speed_hz)
116{
117 u32 mainclk_hz = hw->pdata->mainclk_hz;
118 u32 div, brg;
119
120 for (div = 0; div < 4; div++) {
121 brg = mainclk_hz / speed_hz / (4 << div);
122 /* now we have BRG+1 in brg, so count with that */
123 if (brg < (4 + 1)) {
124 brg = (4 + 1); /* speed_hz too big */
125 break; /* set lowest brg (div is == 0) */
126 }
127 if (brg <= (63 + 1))
128 break; /* we have valid brg and div */
129 }
130 if (div == 4) {
131 div = 3; /* speed_hz too small */
132 brg = (63 + 1); /* set highest brg and div */
133 }
134 brg--;
135 return PSC_SPICFG_SET_BAUD(brg) | PSC_SPICFG_SET_DIV(div);
136}
137
138static inline void au1550_spi_mask_ack_all(struct au1550_spi *hw)
139{
140 hw->regs->psc_spimsk =
141 PSC_SPIMSK_MM | PSC_SPIMSK_RR | PSC_SPIMSK_RO
142 | PSC_SPIMSK_RU | PSC_SPIMSK_TR | PSC_SPIMSK_TO
143 | PSC_SPIMSK_TU | PSC_SPIMSK_SD | PSC_SPIMSK_MD;
144 au_sync();
145
146 hw->regs->psc_spievent =
147 PSC_SPIEVNT_MM | PSC_SPIEVNT_RR | PSC_SPIEVNT_RO
148 | PSC_SPIEVNT_RU | PSC_SPIEVNT_TR | PSC_SPIEVNT_TO
149 | PSC_SPIEVNT_TU | PSC_SPIEVNT_SD | PSC_SPIEVNT_MD;
150 au_sync();
151}
152
153static void au1550_spi_reset_fifos(struct au1550_spi *hw)
154{
155 u32 pcr;
156
157 hw->regs->psc_spipcr = PSC_SPIPCR_RC | PSC_SPIPCR_TC;
158 au_sync();
159 do {
160 pcr = hw->regs->psc_spipcr;
161 au_sync();
162 } while (pcr != 0);
163}
164
165/*
166 * dma transfers are used for the most common spi word size of 8-bits
167 * we cannot easily change already set up dma channels' width, so if we wanted
168 * dma support for more than 8-bit words (up to 24 bits), we would need to
169 * setup dma channels from scratch on each spi transfer, based on bits_per_word
170 * instead we have pre set up 8 bit dma channels supporting spi 4 to 8 bits
171 * transfers, and 9 to 24 bits spi transfers will be done in pio irq based mode
172 * callbacks to handle dma or pio are set up in au1550_spi_bits_handlers_set()
173 */
174static void au1550_spi_chipsel(struct spi_device *spi, int value)
175{
176 struct au1550_spi *hw = spi_master_get_devdata(spi->master);
177 unsigned cspol = spi->mode & SPI_CS_HIGH ? 1 : 0;
178 u32 cfg, stat;
179
180 switch (value) {
181 case BITBANG_CS_INACTIVE:
182 if (hw->pdata->deactivate_cs)
183 hw->pdata->deactivate_cs(hw->pdata, spi->chip_select,
184 cspol);
185 break;
186
187 case BITBANG_CS_ACTIVE:
188 au1550_spi_bits_handlers_set(hw, spi->bits_per_word);
189
190 cfg = hw->regs->psc_spicfg;
191 au_sync();
192 hw->regs->psc_spicfg = cfg & ~PSC_SPICFG_DE_ENABLE;
193 au_sync();
194
195 if (spi->mode & SPI_CPOL)
196 cfg |= PSC_SPICFG_BI;
197 else
198 cfg &= ~PSC_SPICFG_BI;
199 if (spi->mode & SPI_CPHA)
200 cfg &= ~PSC_SPICFG_CDE;
201 else
202 cfg |= PSC_SPICFG_CDE;
203
204 if (spi->mode & SPI_LSB_FIRST)
205 cfg |= PSC_SPICFG_MLF;
206 else
207 cfg &= ~PSC_SPICFG_MLF;
208
209 if (hw->usedma && spi->bits_per_word <= 8)
210 cfg &= ~PSC_SPICFG_DD_DISABLE;
211 else
212 cfg |= PSC_SPICFG_DD_DISABLE;
213 cfg = PSC_SPICFG_CLR_LEN(cfg);
214 cfg |= PSC_SPICFG_SET_LEN(spi->bits_per_word);
215
216 cfg = PSC_SPICFG_CLR_BAUD(cfg);
217 cfg &= ~PSC_SPICFG_SET_DIV(3);
218 cfg |= au1550_spi_baudcfg(hw, spi->max_speed_hz);
219
220 hw->regs->psc_spicfg = cfg | PSC_SPICFG_DE_ENABLE;
221 au_sync();
222 do {
223 stat = hw->regs->psc_spistat;
224 au_sync();
225 } while ((stat & PSC_SPISTAT_DR) == 0);
226
227 if (hw->pdata->activate_cs)
228 hw->pdata->activate_cs(hw->pdata, spi->chip_select,
229 cspol);
230 break;
231 }
232}
233
234static int au1550_spi_setupxfer(struct spi_device *spi, struct spi_transfer *t)
235{
236 struct au1550_spi *hw = spi_master_get_devdata(spi->master);
237 unsigned bpw, hz;
238 u32 cfg, stat;
239
240 bpw = spi->bits_per_word;
241 hz = spi->max_speed_hz;
242 if (t) {
243 if (t->bits_per_word)
244 bpw = t->bits_per_word;
245 if (t->speed_hz)
246 hz = t->speed_hz;
247 }
248
249 if (!hz)
250 return -EINVAL;
251
252 au1550_spi_bits_handlers_set(hw, spi->bits_per_word);
253
254 cfg = hw->regs->psc_spicfg;
255 au_sync();
256 hw->regs->psc_spicfg = cfg & ~PSC_SPICFG_DE_ENABLE;
257 au_sync();
258
259 if (hw->usedma && bpw <= 8)
260 cfg &= ~PSC_SPICFG_DD_DISABLE;
261 else
262 cfg |= PSC_SPICFG_DD_DISABLE;
263 cfg = PSC_SPICFG_CLR_LEN(cfg);
264 cfg |= PSC_SPICFG_SET_LEN(bpw);
265
266 cfg = PSC_SPICFG_CLR_BAUD(cfg);
267 cfg &= ~PSC_SPICFG_SET_DIV(3);
268 cfg |= au1550_spi_baudcfg(hw, hz);
269
270 hw->regs->psc_spicfg = cfg;
271 au_sync();
272
273 if (cfg & PSC_SPICFG_DE_ENABLE) {
274 do {
275 stat = hw->regs->psc_spistat;
276 au_sync();
277 } while ((stat & PSC_SPISTAT_DR) == 0);
278 }
279
280 au1550_spi_reset_fifos(hw);
281 au1550_spi_mask_ack_all(hw);
282 return 0;
283}
284
285/*
286 * for dma spi transfers, we have to setup rx channel, otherwise there is
287 * no reliable way how to recognize that spi transfer is done
288 * dma complete callbacks are called before real spi transfer is finished
289 * and if only tx dma channel is set up (and rx fifo overflow event masked)
290 * spi master done event irq is not generated unless rx fifo is empty (emptied)
291 * so we need rx tmp buffer to use for rx dma if user does not provide one
292 */
293static int au1550_spi_dma_rxtmp_alloc(struct au1550_spi *hw, unsigned size)
294{
295 hw->dma_rx_tmpbuf = kmalloc(size, GFP_KERNEL);
296 if (!hw->dma_rx_tmpbuf)
297 return -ENOMEM;
298 hw->dma_rx_tmpbuf_size = size;
299 hw->dma_rx_tmpbuf_addr = dma_map_single(hw->dev, hw->dma_rx_tmpbuf,
300 size, DMA_FROM_DEVICE);
301 if (dma_mapping_error(hw->dev, hw->dma_rx_tmpbuf_addr)) {
302 kfree(hw->dma_rx_tmpbuf);
303 hw->dma_rx_tmpbuf = 0;
304 hw->dma_rx_tmpbuf_size = 0;
305 return -EFAULT;
306 }
307 return 0;
308}
309
310static void au1550_spi_dma_rxtmp_free(struct au1550_spi *hw)
311{
312 dma_unmap_single(hw->dev, hw->dma_rx_tmpbuf_addr,
313 hw->dma_rx_tmpbuf_size, DMA_FROM_DEVICE);
314 kfree(hw->dma_rx_tmpbuf);
315 hw->dma_rx_tmpbuf = 0;
316 hw->dma_rx_tmpbuf_size = 0;
317}
318
319static int au1550_spi_dma_txrxb(struct spi_device *spi, struct spi_transfer *t)
320{
321 struct au1550_spi *hw = spi_master_get_devdata(spi->master);
322 dma_addr_t dma_tx_addr;
323 dma_addr_t dma_rx_addr;
324 u32 res;
325
326 hw->len = t->len;
327 hw->tx_count = 0;
328 hw->rx_count = 0;
329
330 hw->tx = t->tx_buf;
331 hw->rx = t->rx_buf;
332 dma_tx_addr = t->tx_dma;
333 dma_rx_addr = t->rx_dma;
334
335 /*
336 * check if buffers are already dma mapped, map them otherwise:
337 * - first map the TX buffer, so cache data gets written to memory
338 * - then map the RX buffer, so that cache entries (with
339 * soon-to-be-stale data) get removed
340 * use rx buffer in place of tx if tx buffer was not provided
341 * use temp rx buffer (preallocated or realloc to fit) for rx dma
342 */
343 if (t->tx_buf) {
344 if (t->tx_dma == 0) { /* if DMA_ADDR_INVALID, map it */
345 dma_tx_addr = dma_map_single(hw->dev,
346 (void *)t->tx_buf,
347 t->len, DMA_TO_DEVICE);
348 if (dma_mapping_error(hw->dev, dma_tx_addr))
349 dev_err(hw->dev, "tx dma map error\n");
350 }
351 }
352
353 if (t->rx_buf) {
354 if (t->rx_dma == 0) { /* if DMA_ADDR_INVALID, map it */
355 dma_rx_addr = dma_map_single(hw->dev,
356 (void *)t->rx_buf,
357 t->len, DMA_FROM_DEVICE);
358 if (dma_mapping_error(hw->dev, dma_rx_addr))
359 dev_err(hw->dev, "rx dma map error\n");
360 }
361 } else {
362 if (t->len > hw->dma_rx_tmpbuf_size) {
363 int ret;
364
365 au1550_spi_dma_rxtmp_free(hw);
366 ret = au1550_spi_dma_rxtmp_alloc(hw, max(t->len,
367 AU1550_SPI_DMA_RXTMP_MINSIZE));
368 if (ret < 0)
369 return ret;
370 }
371 hw->rx = hw->dma_rx_tmpbuf;
372 dma_rx_addr = hw->dma_rx_tmpbuf_addr;
373 dma_sync_single_for_device(hw->dev, dma_rx_addr,
374 t->len, DMA_FROM_DEVICE);
375 }
376
377 if (!t->tx_buf) {
378 dma_sync_single_for_device(hw->dev, dma_rx_addr,
379 t->len, DMA_BIDIRECTIONAL);
380 hw->tx = hw->rx;
381 }
382
383 /* put buffers on the ring */
384 res = au1xxx_dbdma_put_dest(hw->dma_rx_ch, virt_to_phys(hw->rx),
385 t->len, DDMA_FLAGS_IE);
386 if (!res)
387 dev_err(hw->dev, "rx dma put dest error\n");
388
389 res = au1xxx_dbdma_put_source(hw->dma_tx_ch, virt_to_phys(hw->tx),
390 t->len, DDMA_FLAGS_IE);
391 if (!res)
392 dev_err(hw->dev, "tx dma put source error\n");
393
394 au1xxx_dbdma_start(hw->dma_rx_ch);
395 au1xxx_dbdma_start(hw->dma_tx_ch);
396
397 /* by default enable nearly all events interrupt */
398 hw->regs->psc_spimsk = PSC_SPIMSK_SD;
399 au_sync();
400
401 /* start the transfer */
402 hw->regs->psc_spipcr = PSC_SPIPCR_MS;
403 au_sync();
404
405 wait_for_completion(&hw->master_done);
406
407 au1xxx_dbdma_stop(hw->dma_tx_ch);
408 au1xxx_dbdma_stop(hw->dma_rx_ch);
409
410 if (!t->rx_buf) {
411 /* using the temporal preallocated and premapped buffer */
412 dma_sync_single_for_cpu(hw->dev, dma_rx_addr, t->len,
413 DMA_FROM_DEVICE);
414 }
415 /* unmap buffers if mapped above */
416 if (t->rx_buf && t->rx_dma == 0 )
417 dma_unmap_single(hw->dev, dma_rx_addr, t->len,
418 DMA_FROM_DEVICE);
419 if (t->tx_buf && t->tx_dma == 0 )
420 dma_unmap_single(hw->dev, dma_tx_addr, t->len,
421 DMA_TO_DEVICE);
422
423 return hw->rx_count < hw->tx_count ? hw->rx_count : hw->tx_count;
424}
425
426static irqreturn_t au1550_spi_dma_irq_callback(struct au1550_spi *hw)
427{
428 u32 stat, evnt;
429
430 stat = hw->regs->psc_spistat;
431 evnt = hw->regs->psc_spievent;
432 au_sync();
433 if ((stat & PSC_SPISTAT_DI) == 0) {
434 dev_err(hw->dev, "Unexpected IRQ!\n");
435 return IRQ_NONE;
436 }
437
438 if ((evnt & (PSC_SPIEVNT_MM | PSC_SPIEVNT_RO
439 | PSC_SPIEVNT_RU | PSC_SPIEVNT_TO
440 | PSC_SPIEVNT_TU | PSC_SPIEVNT_SD))
441 != 0) {
442 /*
443 * due to an spi error we consider transfer as done,
444 * so mask all events until before next transfer start
445 * and stop the possibly running dma immediately
446 */
447 au1550_spi_mask_ack_all(hw);
448 au1xxx_dbdma_stop(hw->dma_rx_ch);
449 au1xxx_dbdma_stop(hw->dma_tx_ch);
450
451 /* get number of transferred bytes */
452 hw->rx_count = hw->len - au1xxx_get_dma_residue(hw->dma_rx_ch);
453 hw->tx_count = hw->len - au1xxx_get_dma_residue(hw->dma_tx_ch);
454
455 au1xxx_dbdma_reset(hw->dma_rx_ch);
456 au1xxx_dbdma_reset(hw->dma_tx_ch);
457 au1550_spi_reset_fifos(hw);
458
459 if (evnt == PSC_SPIEVNT_RO)
460 dev_err(hw->dev,
461 "dma transfer: receive FIFO overflow!\n");
462 else
463 dev_err(hw->dev,
464 "dma transfer: unexpected SPI error "
465 "(event=0x%x stat=0x%x)!\n", evnt, stat);
466
467 complete(&hw->master_done);
468 return IRQ_HANDLED;
469 }
470
471 if ((evnt & PSC_SPIEVNT_MD) != 0) {
472 /* transfer completed successfully */
473 au1550_spi_mask_ack_all(hw);
474 hw->rx_count = hw->len;
475 hw->tx_count = hw->len;
476 complete(&hw->master_done);
477 }
478 return IRQ_HANDLED;
479}
480
481
482/* routines to handle different word sizes in pio mode */
483#define AU1550_SPI_RX_WORD(size, mask) \
484static void au1550_spi_rx_word_##size(struct au1550_spi *hw) \
485{ \
486 u32 fifoword = hw->regs->psc_spitxrx & (u32)(mask); \
487 au_sync(); \
488 if (hw->rx) { \
489 *(u##size *)hw->rx = (u##size)fifoword; \
490 hw->rx += (size) / 8; \
491 } \
492 hw->rx_count += (size) / 8; \
493}
494
495#define AU1550_SPI_TX_WORD(size, mask) \
496static void au1550_spi_tx_word_##size(struct au1550_spi *hw) \
497{ \
498 u32 fifoword = 0; \
499 if (hw->tx) { \
500 fifoword = *(u##size *)hw->tx & (u32)(mask); \
501 hw->tx += (size) / 8; \
502 } \
503 hw->tx_count += (size) / 8; \
504 if (hw->tx_count >= hw->len) \
505 fifoword |= PSC_SPITXRX_LC; \
506 hw->regs->psc_spitxrx = fifoword; \
507 au_sync(); \
508}
509
510AU1550_SPI_RX_WORD(8,0xff)
511AU1550_SPI_RX_WORD(16,0xffff)
512AU1550_SPI_RX_WORD(32,0xffffff)
513AU1550_SPI_TX_WORD(8,0xff)
514AU1550_SPI_TX_WORD(16,0xffff)
515AU1550_SPI_TX_WORD(32,0xffffff)
516
517static int au1550_spi_pio_txrxb(struct spi_device *spi, struct spi_transfer *t)
518{
519 u32 stat, mask;
520 struct au1550_spi *hw = spi_master_get_devdata(spi->master);
521
522 hw->tx = t->tx_buf;
523 hw->rx = t->rx_buf;
524 hw->len = t->len;
525 hw->tx_count = 0;
526 hw->rx_count = 0;
527
528 /* by default enable nearly all events after filling tx fifo */
529 mask = PSC_SPIMSK_SD;
530
531 /* fill the transmit FIFO */
532 while (hw->tx_count < hw->len) {
533
534 hw->tx_word(hw);
535
536 if (hw->tx_count >= hw->len) {
537 /* mask tx fifo request interrupt as we are done */
538 mask |= PSC_SPIMSK_TR;
539 }
540
541 stat = hw->regs->psc_spistat;
542 au_sync();
543 if (stat & PSC_SPISTAT_TF)
544 break;
545 }
546
547 /* enable event interrupts */
548 hw->regs->psc_spimsk = mask;
549 au_sync();
550
551 /* start the transfer */
552 hw->regs->psc_spipcr = PSC_SPIPCR_MS;
553 au_sync();
554
555 wait_for_completion(&hw->master_done);
556
557 return hw->rx_count < hw->tx_count ? hw->rx_count : hw->tx_count;
558}
559
560static irqreturn_t au1550_spi_pio_irq_callback(struct au1550_spi *hw)
561{
562 int busy;
563 u32 stat, evnt;
564
565 stat = hw->regs->psc_spistat;
566 evnt = hw->regs->psc_spievent;
567 au_sync();
568 if ((stat & PSC_SPISTAT_DI) == 0) {
569 dev_err(hw->dev, "Unexpected IRQ!\n");
570 return IRQ_NONE;
571 }
572
573 if ((evnt & (PSC_SPIEVNT_MM | PSC_SPIEVNT_RO
574 | PSC_SPIEVNT_RU | PSC_SPIEVNT_TO
575 | PSC_SPIEVNT_SD))
576 != 0) {
577 /*
578 * due to an error we consider transfer as done,
579 * so mask all events until before next transfer start
580 */
581 au1550_spi_mask_ack_all(hw);
582 au1550_spi_reset_fifos(hw);
583 dev_err(hw->dev,
584 "pio transfer: unexpected SPI error "
585 "(event=0x%x stat=0x%x)!\n", evnt, stat);
586 complete(&hw->master_done);
587 return IRQ_HANDLED;
588 }
589
590 /*
591 * while there is something to read from rx fifo
592 * or there is a space to write to tx fifo:
593 */
594 do {
595 busy = 0;
596 stat = hw->regs->psc_spistat;
597 au_sync();
598
599 /*
600 * Take care to not let the Rx FIFO overflow.
601 *
602 * We only write a byte if we have read one at least. Initially,
603 * the write fifo is full, so we should read from the read fifo
604 * first.
605 * In case we miss a word from the read fifo, we should get a
606 * RO event and should back out.
607 */
608 if (!(stat & PSC_SPISTAT_RE) && hw->rx_count < hw->len) {
609 hw->rx_word(hw);
610 busy = 1;
611
612 if (!(stat & PSC_SPISTAT_TF) && hw->tx_count < hw->len)
613 hw->tx_word(hw);
614 }
615 } while (busy);
616
617 hw->regs->psc_spievent = PSC_SPIEVNT_RR | PSC_SPIEVNT_TR;
618 au_sync();
619
620 /*
621 * Restart the SPI transmission in case of a transmit underflow.
622 * This seems to work despite the notes in the Au1550 data book
623 * of Figure 8-4 with flowchart for SPI master operation:
624 *
625 * """Note 1: An XFR Error Interrupt occurs, unless masked,
626 * for any of the following events: Tx FIFO Underflow,
627 * Rx FIFO Overflow, or Multiple-master Error
628 * Note 2: In case of a Tx Underflow Error, all zeroes are
629 * transmitted."""
630 *
631 * By simply restarting the spi transfer on Tx Underflow Error,
632 * we assume that spi transfer was paused instead of zeroes
633 * transmittion mentioned in the Note 2 of Au1550 data book.
634 */
635 if (evnt & PSC_SPIEVNT_TU) {
636 hw->regs->psc_spievent = PSC_SPIEVNT_TU | PSC_SPIEVNT_MD;
637 au_sync();
638 hw->regs->psc_spipcr = PSC_SPIPCR_MS;
639 au_sync();
640 }
641
642 if (hw->rx_count >= hw->len) {
643 /* transfer completed successfully */
644 au1550_spi_mask_ack_all(hw);
645 complete(&hw->master_done);
646 }
647 return IRQ_HANDLED;
648}
649
650static int au1550_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
651{
652 struct au1550_spi *hw = spi_master_get_devdata(spi->master);
653 return hw->txrx_bufs(spi, t);
654}
655
656static irqreturn_t au1550_spi_irq(int irq, void *dev)
657{
658 struct au1550_spi *hw = dev;
659 return hw->irq_callback(hw);
660}
661
662static void au1550_spi_bits_handlers_set(struct au1550_spi *hw, int bpw)
663{
664 if (bpw <= 8) {
665 if (hw->usedma) {
666 hw->txrx_bufs = &au1550_spi_dma_txrxb;
667 hw->irq_callback = &au1550_spi_dma_irq_callback;
668 } else {
669 hw->rx_word = &au1550_spi_rx_word_8;
670 hw->tx_word = &au1550_spi_tx_word_8;
671 hw->txrx_bufs = &au1550_spi_pio_txrxb;
672 hw->irq_callback = &au1550_spi_pio_irq_callback;
673 }
674 } else if (bpw <= 16) {
675 hw->rx_word = &au1550_spi_rx_word_16;
676 hw->tx_word = &au1550_spi_tx_word_16;
677 hw->txrx_bufs = &au1550_spi_pio_txrxb;
678 hw->irq_callback = &au1550_spi_pio_irq_callback;
679 } else {
680 hw->rx_word = &au1550_spi_rx_word_32;
681 hw->tx_word = &au1550_spi_tx_word_32;
682 hw->txrx_bufs = &au1550_spi_pio_txrxb;
683 hw->irq_callback = &au1550_spi_pio_irq_callback;
684 }
685}
686
687static void au1550_spi_setup_psc_as_spi(struct au1550_spi *hw)
688{
689 u32 stat, cfg;
690
691 /* set up the PSC for SPI mode */
692 hw->regs->psc_ctrl = PSC_CTRL_DISABLE;
693 au_sync();
694 hw->regs->psc_sel = PSC_SEL_PS_SPIMODE;
695 au_sync();
696
697 hw->regs->psc_spicfg = 0;
698 au_sync();
699
700 hw->regs->psc_ctrl = PSC_CTRL_ENABLE;
701 au_sync();
702
703 do {
704 stat = hw->regs->psc_spistat;
705 au_sync();
706 } while ((stat & PSC_SPISTAT_SR) == 0);
707
708
709 cfg = hw->usedma ? 0 : PSC_SPICFG_DD_DISABLE;
710 cfg |= PSC_SPICFG_SET_LEN(8);
711 cfg |= PSC_SPICFG_RT_FIFO8 | PSC_SPICFG_TT_FIFO8;
712 /* use minimal allowed brg and div values as initial setting: */
713 cfg |= PSC_SPICFG_SET_BAUD(4) | PSC_SPICFG_SET_DIV(0);
714
715#ifdef AU1550_SPI_DEBUG_LOOPBACK
716 cfg |= PSC_SPICFG_LB;
717#endif
718
719 hw->regs->psc_spicfg = cfg;
720 au_sync();
721
722 au1550_spi_mask_ack_all(hw);
723
724 hw->regs->psc_spicfg |= PSC_SPICFG_DE_ENABLE;
725 au_sync();
726
727 do {
728 stat = hw->regs->psc_spistat;
729 au_sync();
730 } while ((stat & PSC_SPISTAT_DR) == 0);
731
732 au1550_spi_reset_fifos(hw);
733}
734
735
736static int au1550_spi_probe(struct platform_device *pdev)
737{
738 struct au1550_spi *hw;
739 struct spi_master *master;
740 struct resource *r;
741 int err = 0;
742
743 master = spi_alloc_master(&pdev->dev, sizeof(struct au1550_spi));
744 if (master == NULL) {
745 dev_err(&pdev->dev, "No memory for spi_master\n");
746 err = -ENOMEM;
747 goto err_nomem;
748 }
749
750 /* the spi->mode bits understood by this driver: */
751 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
752 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 24);
753
754 hw = spi_master_get_devdata(master);
755
756 hw->master = master;
757 hw->pdata = dev_get_platdata(&pdev->dev);
758 hw->dev = &pdev->dev;
759
760 if (hw->pdata == NULL) {
761 dev_err(&pdev->dev, "No platform data supplied\n");
762 err = -ENOENT;
763 goto err_no_pdata;
764 }
765
766 r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
767 if (!r) {
768 dev_err(&pdev->dev, "no IRQ\n");
769 err = -ENODEV;
770 goto err_no_iores;
771 }
772 hw->irq = r->start;
773
774 hw->usedma = 0;
775 r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
776 if (r) {
777 hw->dma_tx_id = r->start;
778 r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
779 if (r) {
780 hw->dma_rx_id = r->start;
781 if (usedma && ddma_memid) {
782 if (pdev->dev.dma_mask == NULL)
783 dev_warn(&pdev->dev, "no dma mask\n");
784 else
785 hw->usedma = 1;
786 }
787 }
788 }
789
790 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
791 if (!r) {
792 dev_err(&pdev->dev, "no mmio resource\n");
793 err = -ENODEV;
794 goto err_no_iores;
795 }
796
797 hw->ioarea = request_mem_region(r->start, sizeof(psc_spi_t),
798 pdev->name);
799 if (!hw->ioarea) {
800 dev_err(&pdev->dev, "Cannot reserve iomem region\n");
801 err = -ENXIO;
802 goto err_no_iores;
803 }
804
805 hw->regs = (psc_spi_t __iomem *)ioremap(r->start, sizeof(psc_spi_t));
806 if (!hw->regs) {
807 dev_err(&pdev->dev, "cannot ioremap\n");
808 err = -ENXIO;
809 goto err_ioremap;
810 }
811
812 platform_set_drvdata(pdev, hw);
813
814 init_completion(&hw->master_done);
815
816 hw->bitbang.master = hw->master;
817 hw->bitbang.setup_transfer = au1550_spi_setupxfer;
818 hw->bitbang.chipselect = au1550_spi_chipsel;
819 hw->bitbang.txrx_bufs = au1550_spi_txrx_bufs;
820
821 if (hw->usedma) {
822 hw->dma_tx_ch = au1xxx_dbdma_chan_alloc(ddma_memid,
823 hw->dma_tx_id, NULL, (void *)hw);
824 if (hw->dma_tx_ch == 0) {
825 dev_err(&pdev->dev,
826 "Cannot allocate tx dma channel\n");
827 err = -ENXIO;
828 goto err_no_txdma;
829 }
830 au1xxx_dbdma_set_devwidth(hw->dma_tx_ch, 8);
831 if (au1xxx_dbdma_ring_alloc(hw->dma_tx_ch,
832 AU1550_SPI_DBDMA_DESCRIPTORS) == 0) {
833 dev_err(&pdev->dev,
834 "Cannot allocate tx dma descriptors\n");
835 err = -ENXIO;
836 goto err_no_txdma_descr;
837 }
838
839
840 hw->dma_rx_ch = au1xxx_dbdma_chan_alloc(hw->dma_rx_id,
841 ddma_memid, NULL, (void *)hw);
842 if (hw->dma_rx_ch == 0) {
843 dev_err(&pdev->dev,
844 "Cannot allocate rx dma channel\n");
845 err = -ENXIO;
846 goto err_no_rxdma;
847 }
848 au1xxx_dbdma_set_devwidth(hw->dma_rx_ch, 8);
849 if (au1xxx_dbdma_ring_alloc(hw->dma_rx_ch,
850 AU1550_SPI_DBDMA_DESCRIPTORS) == 0) {
851 dev_err(&pdev->dev,
852 "Cannot allocate rx dma descriptors\n");
853 err = -ENXIO;
854 goto err_no_rxdma_descr;
855 }
856
857 err = au1550_spi_dma_rxtmp_alloc(hw,
858 AU1550_SPI_DMA_RXTMP_MINSIZE);
859 if (err < 0) {
860 dev_err(&pdev->dev,
861 "Cannot allocate initial rx dma tmp buffer\n");
862 goto err_dma_rxtmp_alloc;
863 }
864 }
865
866 au1550_spi_bits_handlers_set(hw, 8);
867
868 err = request_irq(hw->irq, au1550_spi_irq, 0, pdev->name, hw);
869 if (err) {
870 dev_err(&pdev->dev, "Cannot claim IRQ\n");
871 goto err_no_irq;
872 }
873
874 master->bus_num = pdev->id;
875 master->num_chipselect = hw->pdata->num_chipselect;
876
877 /*
878 * precompute valid range for spi freq - from au1550 datasheet:
879 * psc_tempclk = psc_mainclk / (2 << DIV)
880 * spiclk = psc_tempclk / (2 * (BRG + 1))
881 * BRG valid range is 4..63
882 * DIV valid range is 0..3
883 * round the min and max frequencies to values that would still
884 * produce valid brg and div
885 */
886 {
887 int min_div = (2 << 0) * (2 * (4 + 1));
888 int max_div = (2 << 3) * (2 * (63 + 1));
889 master->max_speed_hz = hw->pdata->mainclk_hz / min_div;
890 master->min_speed_hz =
891 hw->pdata->mainclk_hz / (max_div + 1) + 1;
892 }
893
894 au1550_spi_setup_psc_as_spi(hw);
895
896 err = spi_bitbang_start(&hw->bitbang);
897 if (err) {
898 dev_err(&pdev->dev, "Failed to register SPI master\n");
899 goto err_register;
900 }
901
902 dev_info(&pdev->dev,
903 "spi master registered: bus_num=%d num_chipselect=%d\n",
904 master->bus_num, master->num_chipselect);
905
906 return 0;
907
908err_register:
909 free_irq(hw->irq, hw);
910
911err_no_irq:
912 au1550_spi_dma_rxtmp_free(hw);
913
914err_dma_rxtmp_alloc:
915err_no_rxdma_descr:
916 if (hw->usedma)
917 au1xxx_dbdma_chan_free(hw->dma_rx_ch);
918
919err_no_rxdma:
920err_no_txdma_descr:
921 if (hw->usedma)
922 au1xxx_dbdma_chan_free(hw->dma_tx_ch);
923
924err_no_txdma:
925 iounmap((void __iomem *)hw->regs);
926
927err_ioremap:
928 release_resource(hw->ioarea);
929 kfree(hw->ioarea);
930
931err_no_iores:
932err_no_pdata:
933 spi_master_put(hw->master);
934
935err_nomem:
936 return err;
937}
938
939static int au1550_spi_remove(struct platform_device *pdev)
940{
941 struct au1550_spi *hw = platform_get_drvdata(pdev);
942
943 dev_info(&pdev->dev, "spi master remove: bus_num=%d\n",
944 hw->master->bus_num);
945
946 spi_bitbang_stop(&hw->bitbang);
947 free_irq(hw->irq, hw);
948 iounmap((void __iomem *)hw->regs);
949 release_resource(hw->ioarea);
950 kfree(hw->ioarea);
951
952 if (hw->usedma) {
953 au1550_spi_dma_rxtmp_free(hw);
954 au1xxx_dbdma_chan_free(hw->dma_rx_ch);
955 au1xxx_dbdma_chan_free(hw->dma_tx_ch);
956 }
957
958 spi_master_put(hw->master);
959 return 0;
960}
961
962/* work with hotplug and coldplug */
963MODULE_ALIAS("platform:au1550-spi");
964
965static struct platform_driver au1550_spi_drv = {
966 .probe = au1550_spi_probe,
967 .remove = au1550_spi_remove,
968 .driver = {
969 .name = "au1550-spi",
970 .owner = THIS_MODULE,
971 },
972};
973
974static int __init au1550_spi_init(void)
975{
976 /*
977 * create memory device with 8 bits dev_devwidth
978 * needed for proper byte ordering to spi fifo
979 */
980 switch (alchemy_get_cputype()) {
981 case ALCHEMY_CPU_AU1550:
982 case ALCHEMY_CPU_AU1200:
983 case ALCHEMY_CPU_AU1300:
984 break;
985 default:
986 return -ENODEV;
987 }
988
989 if (usedma) {
990 ddma_memid = au1xxx_ddma_add_device(&au1550_spi_mem_dbdev);
991 if (!ddma_memid)
992 printk(KERN_ERR "au1550-spi: cannot add memory"
993 "dbdma device\n");
994 }
995 return platform_driver_register(&au1550_spi_drv);
996}
997module_init(au1550_spi_init);
998
999static void __exit au1550_spi_exit(void)
1000{
1001 if (usedma && ddma_memid)
1002 au1xxx_ddma_del_device(ddma_memid);
1003 platform_driver_unregister(&au1550_spi_drv);
1004}
1005module_exit(au1550_spi_exit);
1006
1007MODULE_DESCRIPTION("Au1550 PSC SPI Driver");
1008MODULE_AUTHOR("Jan Nikitenko <jan.nikitenko@gmail.com>");
1009MODULE_LICENSE("GPL");