1 /*
2     comedi/drivers/gsc_hpdi.c
3     This is a driver for the General Standards Corporation High
4     Speed Parallel Digital Interface rs485 boards.
5 
6     Author:  Frank Mori Hess <fmhess@users.sourceforge.net>
7     Copyright (C) 2003 Coherent Imaging Systems
8 
9     COMEDI - Linux Control and Measurement Device Interface
10     Copyright (C) 1997-8 David A. Schleef <ds@schleef.org>
11 
12     This program is free software; you can redistribute it and/or modify
13     it under the terms of the GNU General Public License as published by
14     the Free Software Foundation; either version 2 of the License, or
15     (at your option) any later version.
16 
17     This program is distributed in the hope that it will be useful,
18     but WITHOUT ANY WARRANTY; without even the implied warranty of
19     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20     GNU General Public License for more details.
21 
22     You should have received a copy of the GNU General Public License
23     along with this program; if not, write to the Free Software
24     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 
26 ************************************************************************/
27 
28 /*
29 
30 Driver: gsc_hpdi
31 Description: General Standards Corporation High
32     Speed Parallel Digital Interface rs485 boards
33 Author: Frank Mori Hess <fmhess@users.sourceforge.net>
34 Status: only receive mode works, transmit not supported
35 Updated: 2003-02-20
36 Devices: [General Standards Corporation] PCI-HPDI32 (gsc_hpdi),
37   PMC-HPDI32
38 
39 Configuration options:
40    [0] - PCI bus of device (optional)
41    [1] - PCI slot of device (optional)
42 
43 There are some additional hpdi models available from GSC for which
44 support could be added to this driver.
45 
46 */
47 
48 #include <linux/interrupt.h>
49 #include "../comedidev.h"
50 #include <linux/delay.h>
51 
52 #include "comedi_pci.h"
53 #include "plx9080.h"
54 #include "comedi_fc.h"
55 
56 static int hpdi_attach(struct comedi_device *dev, struct comedi_devconfig *it);
57 static int hpdi_detach(struct comedi_device *dev);
58 static void abort_dma(struct comedi_device *dev, unsigned int channel);
59 static int hpdi_cmd(struct comedi_device *dev, struct comedi_subdevice *s);
60 static int hpdi_cmd_test(struct comedi_device *dev, struct comedi_subdevice *s,
61 			 struct comedi_cmd *cmd);
62 static int hpdi_cancel(struct comedi_device *dev, struct comedi_subdevice *s);
63 static irqreturn_t handle_interrupt(int irq, void *d);
64 static int dio_config_block_size(struct comedi_device *dev, unsigned int *data);
65 
66 #undef HPDI_DEBUG		/*  disable debugging messages */
67 /* #define HPDI_DEBUG      enable debugging code */
68 
69 #ifdef HPDI_DEBUG
70 #define DEBUG_PRINT(format, args...)  printk(format , ## args)
71 #else
72 #define DEBUG_PRINT(format, args...)
73 #endif
74 
75 #define TIMER_BASE 50		/*  20MHz master clock */
76 #define DMA_BUFFER_SIZE 0x10000
77 #define NUM_DMA_BUFFERS 4
78 #define NUM_DMA_DESCRIPTORS 256
79 
80 /* indices of base address regions */
81 enum base_address_regions {
82 	PLX9080_BADDRINDEX = 0,
83 	HPDI_BADDRINDEX = 2,
84 };
85 
86 enum hpdi_registers {
87 	FIRMWARE_REV_REG = 0x0,
88 	BOARD_CONTROL_REG = 0x4,
89 	BOARD_STATUS_REG = 0x8,
90 	TX_PROG_ALMOST_REG = 0xc,
91 	RX_PROG_ALMOST_REG = 0x10,
92 	FEATURES_REG = 0x14,
93 	FIFO_REG = 0x18,
94 	TX_STATUS_COUNT_REG = 0x1c,
95 	TX_LINE_VALID_COUNT_REG = 0x20,
96 	TX_LINE_INVALID_COUNT_REG = 0x24,
97 	RX_STATUS_COUNT_REG = 0x28,
98 	RX_LINE_COUNT_REG = 0x2c,
99 	INTERRUPT_CONTROL_REG = 0x30,
100 	INTERRUPT_STATUS_REG = 0x34,
101 	TX_CLOCK_DIVIDER_REG = 0x38,
102 	TX_FIFO_SIZE_REG = 0x40,
103 	RX_FIFO_SIZE_REG = 0x44,
104 	TX_FIFO_WORDS_REG = 0x48,
105 	RX_FIFO_WORDS_REG = 0x4c,
106 	INTERRUPT_EDGE_LEVEL_REG = 0x50,
107 	INTERRUPT_POLARITY_REG = 0x54,
108 };
109 
command_channel_valid(unsigned int channel)110 int command_channel_valid(unsigned int channel)
111 {
112 	if (channel == 0 || channel > 6) {
113 		printk(KERN_WARNING
114 		       "gsc_hpdi: bug! invalid cable command channel\n");
115 		return 0;
116 	}
117 	return 1;
118 }
119 
120 /* bit definitions */
121 
122 enum firmware_revision_bits {
123 	FEATURES_REG_PRESENT_BIT = 0x8000,
124 };
firmware_revision(uint32_t fwr_bits)125 int firmware_revision(uint32_t fwr_bits)
126 {
127 	return fwr_bits & 0xff;
128 }
129 
pcb_revision(uint32_t fwr_bits)130 int pcb_revision(uint32_t fwr_bits)
131 {
132 	return (fwr_bits >> 8) & 0xff;
133 }
134 
hpdi_subid(uint32_t fwr_bits)135 int hpdi_subid(uint32_t fwr_bits)
136 {
137 	return (fwr_bits >> 16) & 0xff;
138 }
139 
140 enum board_control_bits {
141 	BOARD_RESET_BIT = 0x1,	/* wait 10usec before accessing fifos */
142 	TX_FIFO_RESET_BIT = 0x2,
143 	RX_FIFO_RESET_BIT = 0x4,
144 	TX_ENABLE_BIT = 0x10,
145 	RX_ENABLE_BIT = 0x20,
146 	DEMAND_DMA_DIRECTION_TX_BIT = 0x40,
147 		/* for ch 0, ch 1 can only transmit (when present) */
148 	LINE_VALID_ON_STATUS_VALID_BIT = 0x80,
149 	START_TX_BIT = 0x10,
150 	CABLE_THROTTLE_ENABLE_BIT = 0x20,
151 	TEST_MODE_ENABLE_BIT = 0x80000000,
152 };
command_discrete_output_bits(unsigned int channel,int output,int output_value)153 uint32_t command_discrete_output_bits(unsigned int channel, int output,
154 				      int output_value)
155 {
156 	uint32_t bits = 0;
157 
158 	if (command_channel_valid(channel) == 0)
159 		return 0;
160 	if (output) {
161 		bits |= 0x1 << (16 + channel);
162 		if (output_value)
163 			bits |= 0x1 << (24 + channel);
164 	} else
165 		bits |= 0x1 << (24 + channel);
166 
167 	return bits;
168 }
169 
170 enum board_status_bits {
171 	COMMAND_LINE_STATUS_MASK = 0x7f,
172 	TX_IN_PROGRESS_BIT = 0x80,
173 	TX_NOT_EMPTY_BIT = 0x100,
174 	TX_NOT_ALMOST_EMPTY_BIT = 0x200,
175 	TX_NOT_ALMOST_FULL_BIT = 0x400,
176 	TX_NOT_FULL_BIT = 0x800,
177 	RX_NOT_EMPTY_BIT = 0x1000,
178 	RX_NOT_ALMOST_EMPTY_BIT = 0x2000,
179 	RX_NOT_ALMOST_FULL_BIT = 0x4000,
180 	RX_NOT_FULL_BIT = 0x8000,
181 	BOARD_JUMPER0_INSTALLED_BIT = 0x10000,
182 	BOARD_JUMPER1_INSTALLED_BIT = 0x20000,
183 	TX_OVERRUN_BIT = 0x200000,
184 	RX_UNDERRUN_BIT = 0x400000,
185 	RX_OVERRUN_BIT = 0x800000,
186 };
187 
almost_full_bits(unsigned int num_words)188 uint32_t almost_full_bits(unsigned int num_words)
189 {
190 /* XXX need to add or subtract one? */
191 	return (num_words << 16) & 0xff0000;
192 }
193 
almost_empty_bits(unsigned int num_words)194 uint32_t almost_empty_bits(unsigned int num_words)
195 {
196 	return num_words & 0xffff;
197 }
198 
almost_full_num_words(uint32_t bits)199 unsigned int almost_full_num_words(uint32_t bits)
200 {
201 /* XXX need to add or subtract one? */
202 	return (bits >> 16) & 0xffff;
203 }
204 
almost_empty_num_words(uint32_t bits)205 unsigned int almost_empty_num_words(uint32_t bits)
206 {
207 	return bits & 0xffff;
208 }
209 
210 enum features_bits {
211 	FIFO_SIZE_PRESENT_BIT = 0x1,
212 	FIFO_WORDS_PRESENT_BIT = 0x2,
213 	LEVEL_EDGE_INTERRUPTS_PRESENT_BIT = 0x4,
214 	GPIO_SUPPORTED_BIT = 0x8,
215 	PLX_DMA_CH1_SUPPORTED_BIT = 0x10,
216 	OVERRUN_UNDERRUN_SUPPORTED_BIT = 0x20,
217 };
218 
219 enum interrupt_sources {
220 	FRAME_VALID_START_INTR = 0,
221 	FRAME_VALID_END_INTR = 1,
222 	TX_FIFO_EMPTY_INTR = 8,
223 	TX_FIFO_ALMOST_EMPTY_INTR = 9,
224 	TX_FIFO_ALMOST_FULL_INTR = 10,
225 	TX_FIFO_FULL_INTR = 11,
226 	RX_EMPTY_INTR = 12,
227 	RX_ALMOST_EMPTY_INTR = 13,
228 	RX_ALMOST_FULL_INTR = 14,
229 	RX_FULL_INTR = 15,
230 };
command_intr_source(unsigned int channel)231 int command_intr_source(unsigned int channel)
232 {
233 	if (command_channel_valid(channel) == 0)
234 		channel = 1;
235 	return channel + 1;
236 }
237 
intr_bit(int interrupt_source)238 uint32_t intr_bit(int interrupt_source)
239 {
240 	return 0x1 << interrupt_source;
241 }
242 
tx_clock_divisor_bits(unsigned int divisor)243 uint32_t tx_clock_divisor_bits(unsigned int divisor)
244 {
245 	return divisor & 0xff;
246 }
247 
fifo_size(uint32_t fifo_size_bits)248 unsigned int fifo_size(uint32_t fifo_size_bits)
249 {
250 	return fifo_size_bits & 0xfffff;
251 }
252 
fifo_words(uint32_t fifo_words_bits)253 unsigned int fifo_words(uint32_t fifo_words_bits)
254 {
255 	return fifo_words_bits & 0xfffff;
256 }
257 
intr_edge_bit(int interrupt_source)258 uint32_t intr_edge_bit(int interrupt_source)
259 {
260 	return 0x1 << interrupt_source;
261 }
262 
intr_active_high_bit(int interrupt_source)263 uint32_t intr_active_high_bit(int interrupt_source)
264 {
265 	return 0x1 << interrupt_source;
266 }
267 
268 struct hpdi_board {
269 
270 	char *name;
271 	int device_id;		/*  pci device id */
272 	int subdevice_id;	/*  pci subdevice id */
273 };
274 
275 static const struct hpdi_board hpdi_boards[] = {
276 	{
277 	 .name = "pci-hpdi32",
278 	 .device_id = PCI_DEVICE_ID_PLX_9080,
279 	 .subdevice_id = 0x2400,
280 	 },
281 #if 0
282 	{
283 	 .name = "pxi-hpdi32",
284 	 .device_id = 0x9656,
285 	 .subdevice_id = 0x2705,
286 	 },
287 #endif
288 };
289 
290 static DEFINE_PCI_DEVICE_TABLE(hpdi_pci_table) = {
291 	{
292 	PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9080, PCI_VENDOR_ID_PLX,
293 		    0x2400, 0, 0, 0}, {
294 	0}
295 };
296 
297 MODULE_DEVICE_TABLE(pci, hpdi_pci_table);
298 
board(const struct comedi_device * dev)299 static inline struct hpdi_board *board(const struct comedi_device *dev)
300 {
301 	return (struct hpdi_board *)dev->board_ptr;
302 }
303 
304 struct hpdi_private {
305 
306 	struct pci_dev *hw_dev;	/*  pointer to board's pci_dev struct */
307 	/*  base addresses (physical) */
308 	resource_size_t plx9080_phys_iobase;
309 	resource_size_t hpdi_phys_iobase;
310 	/*  base addresses (ioremapped) */
311 	void *plx9080_iobase;
312 	void *hpdi_iobase;
313 	uint32_t *dio_buffer[NUM_DMA_BUFFERS];	/*  dma buffers */
314 	/* physical addresses of dma buffers */
315 	dma_addr_t dio_buffer_phys_addr[NUM_DMA_BUFFERS];
316 	/* array of dma descriptors read by plx9080, allocated to get proper
317 	 * alignment */
318 	struct plx_dma_desc *dma_desc;
319 	/* physical address of dma descriptor array */
320 	dma_addr_t dma_desc_phys_addr;
321 	unsigned int num_dma_descriptors;
322 	/* pointer to start of buffers indexed by descriptor */
323 	uint32_t *desc_dio_buffer[NUM_DMA_DESCRIPTORS];
324 	/* index of the dma descriptor that is currently being used */
325 	volatile unsigned int dma_desc_index;
326 	unsigned int tx_fifo_size;
327 	unsigned int rx_fifo_size;
328 	volatile unsigned long dio_count;
329 	/* software copies of values written to hpdi registers */
330 	volatile uint32_t bits[24];
331 	/* number of bytes at which to generate COMEDI_CB_BLOCK events */
332 	volatile unsigned int block_size;
333 	unsigned dio_config_output:1;
334 };
335 
priv(struct comedi_device * dev)336 static inline struct hpdi_private *priv(struct comedi_device *dev)
337 {
338 	return dev->private;
339 }
340 
341 static struct comedi_driver driver_hpdi = {
342 	.driver_name = "gsc_hpdi",
343 	.module = THIS_MODULE,
344 	.attach = hpdi_attach,
345 	.detach = hpdi_detach,
346 };
347 
driver_hpdi_pci_probe(struct pci_dev * dev,const struct pci_device_id * ent)348 static int __devinit driver_hpdi_pci_probe(struct pci_dev *dev,
349 					   const struct pci_device_id *ent)
350 {
351 	return comedi_pci_auto_config(dev, driver_hpdi.driver_name);
352 }
353 
driver_hpdi_pci_remove(struct pci_dev * dev)354 static void __devexit driver_hpdi_pci_remove(struct pci_dev *dev)
355 {
356 	comedi_pci_auto_unconfig(dev);
357 }
358 
359 static struct pci_driver driver_hpdi_pci_driver = {
360 	.id_table = hpdi_pci_table,
361 	.probe = &driver_hpdi_pci_probe,
362 	.remove = __devexit_p(&driver_hpdi_pci_remove)
363 };
364 
driver_hpdi_init_module(void)365 static int __init driver_hpdi_init_module(void)
366 {
367 	int retval;
368 
369 	retval = comedi_driver_register(&driver_hpdi);
370 	if (retval < 0)
371 		return retval;
372 
373 	driver_hpdi_pci_driver.name = (char *)driver_hpdi.driver_name;
374 	return pci_register_driver(&driver_hpdi_pci_driver);
375 }
376 
driver_hpdi_cleanup_module(void)377 static void __exit driver_hpdi_cleanup_module(void)
378 {
379 	pci_unregister_driver(&driver_hpdi_pci_driver);
380 	comedi_driver_unregister(&driver_hpdi);
381 }
382 
383 module_init(driver_hpdi_init_module);
384 module_exit(driver_hpdi_cleanup_module);
385 
dio_config_insn(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_insn * insn,unsigned int * data)386 static int dio_config_insn(struct comedi_device *dev,
387 			   struct comedi_subdevice *s, struct comedi_insn *insn,
388 			   unsigned int *data)
389 {
390 	switch (data[0]) {
391 	case INSN_CONFIG_DIO_OUTPUT:
392 		priv(dev)->dio_config_output = 1;
393 		return insn->n;
394 		break;
395 	case INSN_CONFIG_DIO_INPUT:
396 		priv(dev)->dio_config_output = 0;
397 		return insn->n;
398 		break;
399 	case INSN_CONFIG_DIO_QUERY:
400 		data[1] =
401 		    priv(dev)->dio_config_output ? COMEDI_OUTPUT : COMEDI_INPUT;
402 		return insn->n;
403 		break;
404 	case INSN_CONFIG_BLOCK_SIZE:
405 		return dio_config_block_size(dev, data);
406 		break;
407 	default:
408 		break;
409 	}
410 
411 	return -EINVAL;
412 }
413 
disable_plx_interrupts(struct comedi_device * dev)414 static void disable_plx_interrupts(struct comedi_device *dev)
415 {
416 	writel(0, priv(dev)->plx9080_iobase + PLX_INTRCS_REG);
417 }
418 
419 /* initialize plx9080 chip */
init_plx9080(struct comedi_device * dev)420 static void init_plx9080(struct comedi_device *dev)
421 {
422 	uint32_t bits;
423 	void *plx_iobase = priv(dev)->plx9080_iobase;
424 
425 	/*  plx9080 dump */
426 	DEBUG_PRINT(" plx interrupt status 0x%x\n",
427 		    readl(plx_iobase + PLX_INTRCS_REG));
428 	DEBUG_PRINT(" plx id bits 0x%x\n", readl(plx_iobase + PLX_ID_REG));
429 	DEBUG_PRINT(" plx control reg 0x%x\n",
430 		    readl(priv(dev)->plx9080_iobase + PLX_CONTROL_REG));
431 
432 	DEBUG_PRINT(" plx revision 0x%x\n",
433 		    readl(plx_iobase + PLX_REVISION_REG));
434 	DEBUG_PRINT(" plx dma channel 0 mode 0x%x\n",
435 		    readl(plx_iobase + PLX_DMA0_MODE_REG));
436 	DEBUG_PRINT(" plx dma channel 1 mode 0x%x\n",
437 		    readl(plx_iobase + PLX_DMA1_MODE_REG));
438 	DEBUG_PRINT(" plx dma channel 0 pci address 0x%x\n",
439 		    readl(plx_iobase + PLX_DMA0_PCI_ADDRESS_REG));
440 	DEBUG_PRINT(" plx dma channel 0 local address 0x%x\n",
441 		    readl(plx_iobase + PLX_DMA0_LOCAL_ADDRESS_REG));
442 	DEBUG_PRINT(" plx dma channel 0 transfer size 0x%x\n",
443 		    readl(plx_iobase + PLX_DMA0_TRANSFER_SIZE_REG));
444 	DEBUG_PRINT(" plx dma channel 0 descriptor 0x%x\n",
445 		    readl(plx_iobase + PLX_DMA0_DESCRIPTOR_REG));
446 	DEBUG_PRINT(" plx dma channel 0 command status 0x%x\n",
447 		    readb(plx_iobase + PLX_DMA0_CS_REG));
448 	DEBUG_PRINT(" plx dma channel 0 threshold 0x%x\n",
449 		    readl(plx_iobase + PLX_DMA0_THRESHOLD_REG));
450 	DEBUG_PRINT(" plx bigend 0x%x\n", readl(plx_iobase + PLX_BIGEND_REG));
451 #ifdef __BIG_ENDIAN
452 	bits = BIGEND_DMA0 | BIGEND_DMA1;
453 #else
454 	bits = 0;
455 #endif
456 	writel(bits, priv(dev)->plx9080_iobase + PLX_BIGEND_REG);
457 
458 	disable_plx_interrupts(dev);
459 
460 	abort_dma(dev, 0);
461 	abort_dma(dev, 1);
462 
463 	/*  configure dma0 mode */
464 	bits = 0;
465 	/*  enable ready input */
466 	bits |= PLX_DMA_EN_READYIN_BIT;
467 	/*  enable dma chaining */
468 	bits |= PLX_EN_CHAIN_BIT;
469 	/*  enable interrupt on dma done
470 	 *  (probably don't need this, since chain never finishes) */
471 	bits |= PLX_EN_DMA_DONE_INTR_BIT;
472 	/*  don't increment local address during transfers
473 	 *  (we are transferring from a fixed fifo register) */
474 	bits |= PLX_LOCAL_ADDR_CONST_BIT;
475 	/*  route dma interrupt to pci bus */
476 	bits |= PLX_DMA_INTR_PCI_BIT;
477 	/*  enable demand mode */
478 	bits |= PLX_DEMAND_MODE_BIT;
479 	/*  enable local burst mode */
480 	bits |= PLX_DMA_LOCAL_BURST_EN_BIT;
481 	bits |= PLX_LOCAL_BUS_32_WIDE_BITS;
482 	writel(bits, plx_iobase + PLX_DMA0_MODE_REG);
483 }
484 
485 /* Allocate and initialize the subdevice structures.
486  */
setup_subdevices(struct comedi_device * dev)487 static int setup_subdevices(struct comedi_device *dev)
488 {
489 	struct comedi_subdevice *s;
490 
491 	if (alloc_subdevices(dev, 1) < 0)
492 		return -ENOMEM;
493 
494 	s = dev->subdevices + 0;
495 	/* analog input subdevice */
496 	dev->read_subdev = s;
497 /*	dev->write_subdev = s; */
498 	s->type = COMEDI_SUBD_DIO;
499 	s->subdev_flags =
500 	    SDF_READABLE | SDF_WRITEABLE | SDF_LSAMPL | SDF_CMD_READ;
501 	s->n_chan = 32;
502 	s->len_chanlist = 32;
503 	s->maxdata = 1;
504 	s->range_table = &range_digital;
505 	s->insn_config = dio_config_insn;
506 	s->do_cmd = hpdi_cmd;
507 	s->do_cmdtest = hpdi_cmd_test;
508 	s->cancel = hpdi_cancel;
509 
510 	return 0;
511 }
512 
init_hpdi(struct comedi_device * dev)513 static int init_hpdi(struct comedi_device *dev)
514 {
515 	uint32_t plx_intcsr_bits;
516 
517 	writel(BOARD_RESET_BIT, priv(dev)->hpdi_iobase + BOARD_CONTROL_REG);
518 	udelay(10);
519 
520 	writel(almost_empty_bits(32) | almost_full_bits(32),
521 	       priv(dev)->hpdi_iobase + RX_PROG_ALMOST_REG);
522 	writel(almost_empty_bits(32) | almost_full_bits(32),
523 	       priv(dev)->hpdi_iobase + TX_PROG_ALMOST_REG);
524 
525 	priv(dev)->tx_fifo_size = fifo_size(readl(priv(dev)->hpdi_iobase +
526 						  TX_FIFO_SIZE_REG));
527 	priv(dev)->rx_fifo_size = fifo_size(readl(priv(dev)->hpdi_iobase +
528 						  RX_FIFO_SIZE_REG));
529 
530 	writel(0, priv(dev)->hpdi_iobase + INTERRUPT_CONTROL_REG);
531 
532 	/*  enable interrupts */
533 	plx_intcsr_bits =
534 	    ICS_AERR | ICS_PERR | ICS_PIE | ICS_PLIE | ICS_PAIE | ICS_LIE |
535 	    ICS_DMA0_E;
536 	writel(plx_intcsr_bits, priv(dev)->plx9080_iobase + PLX_INTRCS_REG);
537 
538 	return 0;
539 }
540 
541 /* setup dma descriptors so a link completes every 'transfer_size' bytes */
setup_dma_descriptors(struct comedi_device * dev,unsigned int transfer_size)542 static int setup_dma_descriptors(struct comedi_device *dev,
543 				 unsigned int transfer_size)
544 {
545 	unsigned int buffer_index, buffer_offset;
546 	uint32_t next_bits = PLX_DESC_IN_PCI_BIT | PLX_INTR_TERM_COUNT |
547 	    PLX_XFER_LOCAL_TO_PCI;
548 	unsigned int i;
549 
550 	if (transfer_size > DMA_BUFFER_SIZE)
551 		transfer_size = DMA_BUFFER_SIZE;
552 	transfer_size -= transfer_size % sizeof(uint32_t);
553 	if (transfer_size == 0)
554 		return -1;
555 
556 	DEBUG_PRINT(" transfer_size %i\n", transfer_size);
557 	DEBUG_PRINT(" descriptors at 0x%lx\n",
558 		    (unsigned long)priv(dev)->dma_desc_phys_addr);
559 
560 	buffer_offset = 0;
561 	buffer_index = 0;
562 	for (i = 0; i < NUM_DMA_DESCRIPTORS &&
563 	     buffer_index < NUM_DMA_BUFFERS; i++) {
564 		priv(dev)->dma_desc[i].pci_start_addr =
565 		    cpu_to_le32(priv(dev)->dio_buffer_phys_addr[buffer_index] +
566 				buffer_offset);
567 		priv(dev)->dma_desc[i].local_start_addr = cpu_to_le32(FIFO_REG);
568 		priv(dev)->dma_desc[i].transfer_size =
569 		    cpu_to_le32(transfer_size);
570 		priv(dev)->dma_desc[i].next =
571 		    cpu_to_le32((priv(dev)->dma_desc_phys_addr + (i +
572 								  1) *
573 				 sizeof(priv(dev)->dma_desc[0])) | next_bits);
574 
575 		priv(dev)->desc_dio_buffer[i] =
576 		    priv(dev)->dio_buffer[buffer_index] +
577 		    (buffer_offset / sizeof(uint32_t));
578 
579 		buffer_offset += transfer_size;
580 		if (transfer_size + buffer_offset > DMA_BUFFER_SIZE) {
581 			buffer_offset = 0;
582 			buffer_index++;
583 		}
584 
585 		DEBUG_PRINT(" desc %i\n", i);
586 		DEBUG_PRINT(" start addr virt 0x%p, phys 0x%lx\n",
587 			    priv(dev)->desc_dio_buffer[i],
588 			    (unsigned long)priv(dev)->dma_desc[i].
589 			    pci_start_addr);
590 		DEBUG_PRINT(" next 0x%lx\n",
591 			    (unsigned long)priv(dev)->dma_desc[i].next);
592 	}
593 	priv(dev)->num_dma_descriptors = i;
594 	/*  fix last descriptor to point back to first */
595 	priv(dev)->dma_desc[i - 1].next =
596 	    cpu_to_le32(priv(dev)->dma_desc_phys_addr | next_bits);
597 	DEBUG_PRINT(" desc %i next fixup 0x%lx\n", i - 1,
598 		    (unsigned long)priv(dev)->dma_desc[i - 1].next);
599 
600 	priv(dev)->block_size = transfer_size;
601 
602 	return transfer_size;
603 }
604 
hpdi_attach(struct comedi_device * dev,struct comedi_devconfig * it)605 static int hpdi_attach(struct comedi_device *dev, struct comedi_devconfig *it)
606 {
607 	struct pci_dev *pcidev;
608 	int i;
609 	int retval;
610 
611 	printk(KERN_WARNING "comedi%d: gsc_hpdi\n", dev->minor);
612 
613 	if (alloc_private(dev, sizeof(struct hpdi_private)) < 0)
614 		return -ENOMEM;
615 
616 	pcidev = NULL;
617 	for (i = 0; i < ARRAY_SIZE(hpdi_boards) &&
618 		    dev->board_ptr == NULL; i++) {
619 		do {
620 			pcidev = pci_get_subsys(PCI_VENDOR_ID_PLX,
621 						hpdi_boards[i].device_id,
622 						PCI_VENDOR_ID_PLX,
623 						hpdi_boards[i].subdevice_id,
624 						pcidev);
625 			/*  was a particular bus/slot requested? */
626 			if (it->options[0] || it->options[1]) {
627 				/*  are we on the wrong bus/slot? */
628 				if (pcidev->bus->number != it->options[0] ||
629 				    PCI_SLOT(pcidev->devfn) != it->options[1])
630 					continue;
631 			}
632 			if (pcidev) {
633 				priv(dev)->hw_dev = pcidev;
634 				dev->board_ptr = hpdi_boards + i;
635 				break;
636 			}
637 		} while (pcidev != NULL);
638 	}
639 	if (dev->board_ptr == NULL) {
640 		printk(KERN_WARNING "gsc_hpdi: no hpdi card found\n");
641 		return -EIO;
642 	}
643 
644 	printk(KERN_WARNING
645 	       "gsc_hpdi: found %s on bus %i, slot %i\n", board(dev)->name,
646 	       pcidev->bus->number, PCI_SLOT(pcidev->devfn));
647 
648 	if (comedi_pci_enable(pcidev, driver_hpdi.driver_name)) {
649 		printk(KERN_WARNING
650 		       " failed enable PCI device and request regions\n");
651 		return -EIO;
652 	}
653 	pci_set_master(pcidev);
654 
655 	/* Initialize dev->board_name */
656 	dev->board_name = board(dev)->name;
657 
658 	priv(dev)->plx9080_phys_iobase =
659 	    pci_resource_start(pcidev, PLX9080_BADDRINDEX);
660 	priv(dev)->hpdi_phys_iobase =
661 	    pci_resource_start(pcidev, HPDI_BADDRINDEX);
662 
663 	/*  remap, won't work with 2.0 kernels but who cares */
664 	priv(dev)->plx9080_iobase = ioremap(priv(dev)->plx9080_phys_iobase,
665 					    pci_resource_len(pcidev,
666 					    PLX9080_BADDRINDEX));
667 	priv(dev)->hpdi_iobase =
668 	    ioremap(priv(dev)->hpdi_phys_iobase,
669 		    pci_resource_len(pcidev, HPDI_BADDRINDEX));
670 	if (!priv(dev)->plx9080_iobase || !priv(dev)->hpdi_iobase) {
671 		printk(KERN_WARNING " failed to remap io memory\n");
672 		return -ENOMEM;
673 	}
674 
675 	DEBUG_PRINT(" plx9080 remapped to 0x%p\n", priv(dev)->plx9080_iobase);
676 	DEBUG_PRINT(" hpdi remapped to 0x%p\n", priv(dev)->hpdi_iobase);
677 
678 	init_plx9080(dev);
679 
680 	/*  get irq */
681 	if (request_irq(pcidev->irq, handle_interrupt, IRQF_SHARED,
682 			driver_hpdi.driver_name, dev)) {
683 		printk(KERN_WARNING
684 		       " unable to allocate irq %u\n", pcidev->irq);
685 		return -EINVAL;
686 	}
687 	dev->irq = pcidev->irq;
688 
689 	printk(KERN_WARNING " irq %u\n", dev->irq);
690 
691 	/*  alocate pci dma buffers */
692 	for (i = 0; i < NUM_DMA_BUFFERS; i++) {
693 		priv(dev)->dio_buffer[i] =
694 		    pci_alloc_consistent(priv(dev)->hw_dev, DMA_BUFFER_SIZE,
695 					 &priv(dev)->dio_buffer_phys_addr[i]);
696 		DEBUG_PRINT("dio_buffer at virt 0x%p, phys 0x%lx\n",
697 			    priv(dev)->dio_buffer[i],
698 			    (unsigned long)priv(dev)->dio_buffer_phys_addr[i]);
699 	}
700 	/*  allocate dma descriptors */
701 	priv(dev)->dma_desc = pci_alloc_consistent(priv(dev)->hw_dev,
702 						   sizeof(struct plx_dma_desc) *
703 						   NUM_DMA_DESCRIPTORS,
704 						   &priv(dev)->
705 						   dma_desc_phys_addr);
706 	if (priv(dev)->dma_desc_phys_addr & 0xf) {
707 		printk(KERN_WARNING
708 		       " dma descriptors not quad-word aligned (bug)\n");
709 		return -EIO;
710 	}
711 
712 	retval = setup_dma_descriptors(dev, 0x1000);
713 	if (retval < 0)
714 		return retval;
715 
716 	retval = setup_subdevices(dev);
717 	if (retval < 0)
718 		return retval;
719 
720 	return init_hpdi(dev);
721 }
722 
hpdi_detach(struct comedi_device * dev)723 static int hpdi_detach(struct comedi_device *dev)
724 {
725 	unsigned int i;
726 
727 	printk(KERN_WARNING "comedi%d: gsc_hpdi: remove\n", dev->minor);
728 
729 	if (dev->irq)
730 		free_irq(dev->irq, dev);
731 	if ((priv(dev)) && (priv(dev)->hw_dev)) {
732 		if (priv(dev)->plx9080_iobase) {
733 			disable_plx_interrupts(dev);
734 			iounmap((void *)priv(dev)->plx9080_iobase);
735 		}
736 		if (priv(dev)->hpdi_iobase)
737 			iounmap((void *)priv(dev)->hpdi_iobase);
738 		/*  free pci dma buffers */
739 		for (i = 0; i < NUM_DMA_BUFFERS; i++) {
740 			if (priv(dev)->dio_buffer[i])
741 				pci_free_consistent(priv(dev)->hw_dev,
742 						    DMA_BUFFER_SIZE,
743 						    priv(dev)->
744 						    dio_buffer[i],
745 						    priv
746 						    (dev)->dio_buffer_phys_addr
747 						    [i]);
748 		}
749 		/*  free dma descriptors */
750 		if (priv(dev)->dma_desc)
751 			pci_free_consistent(priv(dev)->hw_dev,
752 					    sizeof(struct plx_dma_desc)
753 					    * NUM_DMA_DESCRIPTORS,
754 					    priv(dev)->dma_desc,
755 					    priv(dev)->
756 					    dma_desc_phys_addr);
757 		if (priv(dev)->hpdi_phys_iobase)
758 			comedi_pci_disable(priv(dev)->hw_dev);
759 		pci_dev_put(priv(dev)->hw_dev);
760 	}
761 	return 0;
762 }
763 
dio_config_block_size(struct comedi_device * dev,unsigned int * data)764 static int dio_config_block_size(struct comedi_device *dev, unsigned int *data)
765 {
766 	unsigned int requested_block_size;
767 	int retval;
768 
769 	requested_block_size = data[1];
770 
771 	retval = setup_dma_descriptors(dev, requested_block_size);
772 	if (retval < 0)
773 		return retval;
774 
775 	data[1] = retval;
776 
777 	return 2;
778 }
779 
di_cmd_test(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_cmd * cmd)780 static int di_cmd_test(struct comedi_device *dev, struct comedi_subdevice *s,
781 		       struct comedi_cmd *cmd)
782 {
783 	int err = 0;
784 	int tmp;
785 	int i;
786 
787 	/* step 1: make sure trigger sources are trivially valid */
788 
789 	tmp = cmd->start_src;
790 	cmd->start_src &= TRIG_NOW;
791 	if (!cmd->start_src || tmp != cmd->start_src)
792 		err++;
793 
794 	tmp = cmd->scan_begin_src;
795 	cmd->scan_begin_src &= TRIG_EXT;
796 	if (!cmd->scan_begin_src || tmp != cmd->scan_begin_src)
797 		err++;
798 
799 	tmp = cmd->convert_src;
800 	cmd->convert_src &= TRIG_NOW;
801 	if (!cmd->convert_src || tmp != cmd->convert_src)
802 		err++;
803 
804 	tmp = cmd->scan_end_src;
805 	cmd->scan_end_src &= TRIG_COUNT;
806 	if (!cmd->scan_end_src || tmp != cmd->scan_end_src)
807 		err++;
808 
809 	tmp = cmd->stop_src;
810 	cmd->stop_src &= TRIG_COUNT | TRIG_NONE;
811 	if (!cmd->stop_src || tmp != cmd->stop_src)
812 		err++;
813 
814 	if (err)
815 		return 1;
816 
817 	/* step 2: make sure trigger sources are unique and mutually
818 	 * compatible */
819 
820 	/*  uniqueness check */
821 	if (cmd->stop_src != TRIG_COUNT && cmd->stop_src != TRIG_NONE)
822 		err++;
823 
824 	if (err)
825 		return 2;
826 
827 	/* step 3: make sure arguments are trivially compatible */
828 
829 	if (!cmd->chanlist_len) {
830 		cmd->chanlist_len = 32;
831 		err++;
832 	}
833 	if (cmd->scan_end_arg != cmd->chanlist_len) {
834 		cmd->scan_end_arg = cmd->chanlist_len;
835 		err++;
836 	}
837 
838 	switch (cmd->stop_src) {
839 	case TRIG_COUNT:
840 		if (!cmd->stop_arg) {
841 			cmd->stop_arg = 1;
842 			err++;
843 		}
844 		break;
845 	case TRIG_NONE:
846 		if (cmd->stop_arg != 0) {
847 			cmd->stop_arg = 0;
848 			err++;
849 		}
850 		break;
851 	default:
852 		break;
853 	}
854 
855 	if (err)
856 		return 3;
857 
858 	/* step 4: fix up any arguments */
859 
860 	if (err)
861 		return 4;
862 
863 	if (!cmd->chanlist)
864 		return 0;
865 
866 	for (i = 1; i < cmd->chanlist_len; i++) {
867 		if (CR_CHAN(cmd->chanlist[i]) != i) {
868 			/*  XXX could support 8 or 16 channels */
869 			comedi_error(dev,
870 				     "chanlist must be ch 0 to 31 in order");
871 			err++;
872 			break;
873 		}
874 	}
875 
876 	if (err)
877 		return 5;
878 
879 	return 0;
880 }
881 
hpdi_cmd_test(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_cmd * cmd)882 static int hpdi_cmd_test(struct comedi_device *dev, struct comedi_subdevice *s,
883 			 struct comedi_cmd *cmd)
884 {
885 	if (priv(dev)->dio_config_output)
886 		return -EINVAL;
887 	else
888 		return di_cmd_test(dev, s, cmd);
889 }
890 
hpdi_writel(struct comedi_device * dev,uint32_t bits,unsigned int offset)891 static inline void hpdi_writel(struct comedi_device *dev, uint32_t bits,
892 			       unsigned int offset)
893 {
894 	writel(bits | priv(dev)->bits[offset / sizeof(uint32_t)],
895 	       priv(dev)->hpdi_iobase + offset);
896 }
897 
di_cmd(struct comedi_device * dev,struct comedi_subdevice * s)898 static int di_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
899 {
900 	uint32_t bits;
901 	unsigned long flags;
902 	struct comedi_async *async = s->async;
903 	struct comedi_cmd *cmd = &async->cmd;
904 
905 	hpdi_writel(dev, RX_FIFO_RESET_BIT, BOARD_CONTROL_REG);
906 
907 	DEBUG_PRINT("hpdi: in di_cmd\n");
908 
909 	abort_dma(dev, 0);
910 
911 	priv(dev)->dma_desc_index = 0;
912 
913 	/* These register are supposedly unused during chained dma,
914 	 * but I have found that left over values from last operation
915 	 * occasionally cause problems with transfer of first dma
916 	 * block.  Initializing them to zero seems to fix the problem. */
917 	writel(0, priv(dev)->plx9080_iobase + PLX_DMA0_TRANSFER_SIZE_REG);
918 	writel(0, priv(dev)->plx9080_iobase + PLX_DMA0_PCI_ADDRESS_REG);
919 	writel(0, priv(dev)->plx9080_iobase + PLX_DMA0_LOCAL_ADDRESS_REG);
920 	/*  give location of first dma descriptor */
921 	bits =
922 	    priv(dev)->dma_desc_phys_addr | PLX_DESC_IN_PCI_BIT |
923 	    PLX_INTR_TERM_COUNT | PLX_XFER_LOCAL_TO_PCI;
924 	writel(bits, priv(dev)->plx9080_iobase + PLX_DMA0_DESCRIPTOR_REG);
925 
926 	/*  spinlock for plx dma control/status reg */
927 	spin_lock_irqsave(&dev->spinlock, flags);
928 	/*  enable dma transfer */
929 	writeb(PLX_DMA_EN_BIT | PLX_DMA_START_BIT | PLX_CLEAR_DMA_INTR_BIT,
930 	       priv(dev)->plx9080_iobase + PLX_DMA0_CS_REG);
931 	spin_unlock_irqrestore(&dev->spinlock, flags);
932 
933 	if (cmd->stop_src == TRIG_COUNT)
934 		priv(dev)->dio_count = cmd->stop_arg;
935 	else
936 		priv(dev)->dio_count = 1;
937 
938 	/*  clear over/under run status flags */
939 	writel(RX_UNDERRUN_BIT | RX_OVERRUN_BIT,
940 	       priv(dev)->hpdi_iobase + BOARD_STATUS_REG);
941 	/*  enable interrupts */
942 	writel(intr_bit(RX_FULL_INTR),
943 	       priv(dev)->hpdi_iobase + INTERRUPT_CONTROL_REG);
944 
945 	DEBUG_PRINT("hpdi: starting rx\n");
946 	hpdi_writel(dev, RX_ENABLE_BIT, BOARD_CONTROL_REG);
947 
948 	return 0;
949 }
950 
hpdi_cmd(struct comedi_device * dev,struct comedi_subdevice * s)951 static int hpdi_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
952 {
953 	if (priv(dev)->dio_config_output)
954 		return -EINVAL;
955 	else
956 		return di_cmd(dev, s);
957 }
958 
drain_dma_buffers(struct comedi_device * dev,unsigned int channel)959 static void drain_dma_buffers(struct comedi_device *dev, unsigned int channel)
960 {
961 	struct comedi_async *async = dev->read_subdev->async;
962 	uint32_t next_transfer_addr;
963 	int j;
964 	int num_samples = 0;
965 	void *pci_addr_reg;
966 
967 	if (channel)
968 		pci_addr_reg =
969 		    priv(dev)->plx9080_iobase + PLX_DMA1_PCI_ADDRESS_REG;
970 	else
971 		pci_addr_reg =
972 		    priv(dev)->plx9080_iobase + PLX_DMA0_PCI_ADDRESS_REG;
973 
974 	/*  loop until we have read all the full buffers */
975 	j = 0;
976 	for (next_transfer_addr = readl(pci_addr_reg);
977 	     (next_transfer_addr <
978 	      le32_to_cpu(priv(dev)->dma_desc[priv(dev)->dma_desc_index].
979 			  pci_start_addr)
980 	      || next_transfer_addr >=
981 	      le32_to_cpu(priv(dev)->dma_desc[priv(dev)->dma_desc_index].
982 			  pci_start_addr) + priv(dev)->block_size)
983 	     && j < priv(dev)->num_dma_descriptors; j++) {
984 		/*  transfer data from dma buffer to comedi buffer */
985 		num_samples = priv(dev)->block_size / sizeof(uint32_t);
986 		if (async->cmd.stop_src == TRIG_COUNT) {
987 			if (num_samples > priv(dev)->dio_count)
988 				num_samples = priv(dev)->dio_count;
989 			priv(dev)->dio_count -= num_samples;
990 		}
991 		cfc_write_array_to_buffer(dev->read_subdev,
992 					  priv(dev)->desc_dio_buffer[priv(dev)->
993 								     dma_desc_index],
994 					  num_samples * sizeof(uint32_t));
995 		priv(dev)->dma_desc_index++;
996 		priv(dev)->dma_desc_index %= priv(dev)->num_dma_descriptors;
997 
998 		DEBUG_PRINT("next desc addr 0x%lx\n", (unsigned long)
999 			    priv(dev)->dma_desc[priv(dev)->dma_desc_index].
1000 			    next);
1001 		DEBUG_PRINT("pci addr reg 0x%x\n", next_transfer_addr);
1002 	}
1003 	/*  XXX check for buffer overrun somehow */
1004 }
1005 
handle_interrupt(int irq,void * d)1006 static irqreturn_t handle_interrupt(int irq, void *d)
1007 {
1008 	struct comedi_device *dev = d;
1009 	struct comedi_subdevice *s = dev->read_subdev;
1010 	struct comedi_async *async = s->async;
1011 	uint32_t hpdi_intr_status, hpdi_board_status;
1012 	uint32_t plx_status;
1013 	uint32_t plx_bits;
1014 	uint8_t dma0_status, dma1_status;
1015 	unsigned long flags;
1016 
1017 	if (!dev->attached)
1018 		return IRQ_NONE;
1019 
1020 	plx_status = readl(priv(dev)->plx9080_iobase + PLX_INTRCS_REG);
1021 	if ((plx_status & (ICS_DMA0_A | ICS_DMA1_A | ICS_LIA)) == 0)
1022 		return IRQ_NONE;
1023 
1024 	hpdi_intr_status = readl(priv(dev)->hpdi_iobase + INTERRUPT_STATUS_REG);
1025 	hpdi_board_status = readl(priv(dev)->hpdi_iobase + BOARD_STATUS_REG);
1026 
1027 	async->events = 0;
1028 
1029 	if (hpdi_intr_status) {
1030 		DEBUG_PRINT("hpdi: intr status 0x%x, ", hpdi_intr_status);
1031 		writel(hpdi_intr_status,
1032 		       priv(dev)->hpdi_iobase + INTERRUPT_STATUS_REG);
1033 	}
1034 	/*  spin lock makes sure no one else changes plx dma control reg */
1035 	spin_lock_irqsave(&dev->spinlock, flags);
1036 	dma0_status = readb(priv(dev)->plx9080_iobase + PLX_DMA0_CS_REG);
1037 	if (plx_status & ICS_DMA0_A) {	/*  dma chan 0 interrupt */
1038 		writeb((dma0_status & PLX_DMA_EN_BIT) | PLX_CLEAR_DMA_INTR_BIT,
1039 		       priv(dev)->plx9080_iobase + PLX_DMA0_CS_REG);
1040 
1041 		DEBUG_PRINT("dma0 status 0x%x\n", dma0_status);
1042 		if (dma0_status & PLX_DMA_EN_BIT)
1043 			drain_dma_buffers(dev, 0);
1044 		DEBUG_PRINT(" cleared dma ch0 interrupt\n");
1045 	}
1046 	spin_unlock_irqrestore(&dev->spinlock, flags);
1047 
1048 	/*  spin lock makes sure no one else changes plx dma control reg */
1049 	spin_lock_irqsave(&dev->spinlock, flags);
1050 	dma1_status = readb(priv(dev)->plx9080_iobase + PLX_DMA1_CS_REG);
1051 	if (plx_status & ICS_DMA1_A) {	/*  XXX *//*  dma chan 1 interrupt */
1052 		writeb((dma1_status & PLX_DMA_EN_BIT) | PLX_CLEAR_DMA_INTR_BIT,
1053 		       priv(dev)->plx9080_iobase + PLX_DMA1_CS_REG);
1054 		DEBUG_PRINT("dma1 status 0x%x\n", dma1_status);
1055 
1056 		DEBUG_PRINT(" cleared dma ch1 interrupt\n");
1057 	}
1058 	spin_unlock_irqrestore(&dev->spinlock, flags);
1059 
1060 	/*  clear possible plx9080 interrupt sources */
1061 	if (plx_status & ICS_LDIA) {	/*  clear local doorbell interrupt */
1062 		plx_bits = readl(priv(dev)->plx9080_iobase + PLX_DBR_OUT_REG);
1063 		writel(plx_bits, priv(dev)->plx9080_iobase + PLX_DBR_OUT_REG);
1064 		DEBUG_PRINT(" cleared local doorbell bits 0x%x\n", plx_bits);
1065 	}
1066 
1067 	if (hpdi_board_status & RX_OVERRUN_BIT) {
1068 		comedi_error(dev, "rx fifo overrun");
1069 		async->events |= COMEDI_CB_EOA | COMEDI_CB_ERROR;
1070 		DEBUG_PRINT("dma0_status 0x%x\n",
1071 			    (int)readb(priv(dev)->plx9080_iobase +
1072 				       PLX_DMA0_CS_REG));
1073 	}
1074 
1075 	if (hpdi_board_status & RX_UNDERRUN_BIT) {
1076 		comedi_error(dev, "rx fifo underrun");
1077 		async->events |= COMEDI_CB_EOA | COMEDI_CB_ERROR;
1078 	}
1079 
1080 	if (priv(dev)->dio_count == 0)
1081 		async->events |= COMEDI_CB_EOA;
1082 
1083 	DEBUG_PRINT("board status 0x%x, ", hpdi_board_status);
1084 	DEBUG_PRINT("plx status 0x%x\n", plx_status);
1085 	if (async->events)
1086 		DEBUG_PRINT(" events 0x%x\n", async->events);
1087 
1088 	cfc_handle_events(dev, s);
1089 
1090 	return IRQ_HANDLED;
1091 }
1092 
abort_dma(struct comedi_device * dev,unsigned int channel)1093 static void abort_dma(struct comedi_device *dev, unsigned int channel)
1094 {
1095 	unsigned long flags;
1096 
1097 	/*  spinlock for plx dma control/status reg */
1098 	spin_lock_irqsave(&dev->spinlock, flags);
1099 
1100 	plx9080_abort_dma(priv(dev)->plx9080_iobase, channel);
1101 
1102 	spin_unlock_irqrestore(&dev->spinlock, flags);
1103 }
1104 
hpdi_cancel(struct comedi_device * dev,struct comedi_subdevice * s)1105 static int hpdi_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
1106 {
1107 	hpdi_writel(dev, 0, BOARD_CONTROL_REG);
1108 
1109 	writel(0, priv(dev)->hpdi_iobase + INTERRUPT_CONTROL_REG);
1110 
1111 	abort_dma(dev, 0);
1112 
1113 	return 0;
1114 }
1115 
1116 MODULE_AUTHOR("Comedi http://www.comedi.org");
1117 MODULE_DESCRIPTION("Comedi low-level driver");
1118 MODULE_LICENSE("GPL");
1119