xref: /openbmc/linux/drivers/memstick/host/r592.c (revision 9b799b78)
1 /*
2  * Copyright (C) 2010 - Maxim Levitsky
3  * driver for Ricoh memstick readers
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/freezer.h>
13 #include <linux/jiffies.h>
14 #include <linux/interrupt.h>
15 #include <linux/pci.h>
16 #include <linux/pci_ids.h>
17 #include <linux/delay.h>
18 #include <linux/slab.h>
19 #include <linux/kthread.h>
20 #include <linux/sched.h>
21 #include <linux/highmem.h>
22 #include <asm/byteorder.h>
23 #include <linux/swab.h>
24 #include "r592.h"
25 
26 static bool r592_enable_dma = 1;
27 static int debug;
28 
29 static const char *tpc_names[] = {
30 	"MS_TPC_READ_MG_STATUS",
31 	"MS_TPC_READ_LONG_DATA",
32 	"MS_TPC_READ_SHORT_DATA",
33 	"MS_TPC_READ_REG",
34 	"MS_TPC_READ_QUAD_DATA",
35 	"INVALID",
36 	"MS_TPC_GET_INT",
37 	"MS_TPC_SET_RW_REG_ADRS",
38 	"MS_TPC_EX_SET_CMD",
39 	"MS_TPC_WRITE_QUAD_DATA",
40 	"MS_TPC_WRITE_REG",
41 	"MS_TPC_WRITE_SHORT_DATA",
42 	"MS_TPC_WRITE_LONG_DATA",
43 	"MS_TPC_SET_CMD",
44 };
45 
46 /**
47  * memstick_debug_get_tpc_name - debug helper that returns string for
48  * a TPC number
49  */
50 const char *memstick_debug_get_tpc_name(int tpc)
51 {
52 	return tpc_names[tpc-1];
53 }
54 EXPORT_SYMBOL(memstick_debug_get_tpc_name);
55 
56 
57 /* Read a register*/
58 static inline u32 r592_read_reg(struct r592_device *dev, int address)
59 {
60 	u32 value = readl(dev->mmio + address);
61 	dbg_reg("reg #%02d == 0x%08x", address, value);
62 	return value;
63 }
64 
65 /* Write a register */
66 static inline void r592_write_reg(struct r592_device *dev,
67 							int address, u32 value)
68 {
69 	dbg_reg("reg #%02d <- 0x%08x", address, value);
70 	writel(value, dev->mmio + address);
71 }
72 
73 /* Reads a big endian DWORD register */
74 static inline u32 r592_read_reg_raw_be(struct r592_device *dev, int address)
75 {
76 	u32 value = __raw_readl(dev->mmio + address);
77 	dbg_reg("reg #%02d == 0x%08x", address, value);
78 	return be32_to_cpu(value);
79 }
80 
81 /* Writes a big endian DWORD register */
82 static inline void r592_write_reg_raw_be(struct r592_device *dev,
83 							int address, u32 value)
84 {
85 	dbg_reg("reg #%02d <- 0x%08x", address, value);
86 	__raw_writel(cpu_to_be32(value), dev->mmio + address);
87 }
88 
89 /* Set specific bits in a register (little endian) */
90 static inline void r592_set_reg_mask(struct r592_device *dev,
91 							int address, u32 mask)
92 {
93 	u32 reg = readl(dev->mmio + address);
94 	dbg_reg("reg #%02d |= 0x%08x (old =0x%08x)", address, mask, reg);
95 	writel(reg | mask , dev->mmio + address);
96 }
97 
98 /* Clear specific bits in a register (little endian) */
99 static inline void r592_clear_reg_mask(struct r592_device *dev,
100 						int address, u32 mask)
101 {
102 	u32 reg = readl(dev->mmio + address);
103 	dbg_reg("reg #%02d &= 0x%08x (old = 0x%08x, mask = 0x%08x)",
104 						address, ~mask, reg, mask);
105 	writel(reg & ~mask, dev->mmio + address);
106 }
107 
108 
109 /* Wait for status bits while checking for errors */
110 static int r592_wait_status(struct r592_device *dev, u32 mask, u32 wanted_mask)
111 {
112 	unsigned long timeout = jiffies + msecs_to_jiffies(1000);
113 	u32 reg = r592_read_reg(dev, R592_STATUS);
114 
115 	if ((reg & mask) == wanted_mask)
116 		return 0;
117 
118 	while (time_before(jiffies, timeout)) {
119 
120 		reg = r592_read_reg(dev, R592_STATUS);
121 
122 		if ((reg & mask) == wanted_mask)
123 			return 0;
124 
125 		if (reg & (R592_STATUS_SEND_ERR | R592_STATUS_RECV_ERR))
126 			return -EIO;
127 
128 		cpu_relax();
129 	}
130 	return -ETIME;
131 }
132 
133 
134 /* Enable/disable device */
135 static int r592_enable_device(struct r592_device *dev, bool enable)
136 {
137 	dbg("%sabling the device", enable ? "en" : "dis");
138 
139 	if (enable) {
140 
141 		/* Power up the card */
142 		r592_write_reg(dev, R592_POWER, R592_POWER_0 | R592_POWER_1);
143 
144 		/* Perform a reset */
145 		r592_set_reg_mask(dev, R592_IO, R592_IO_RESET);
146 
147 		msleep(100);
148 	} else
149 		/* Power down the card */
150 		r592_write_reg(dev, R592_POWER, 0);
151 
152 	return 0;
153 }
154 
155 /* Set serial/parallel mode */
156 static int r592_set_mode(struct r592_device *dev, bool parallel_mode)
157 {
158 	if (!parallel_mode) {
159 		dbg("switching to serial mode");
160 
161 		/* Set serial mode */
162 		r592_write_reg(dev, R592_IO_MODE, R592_IO_MODE_SERIAL);
163 
164 		r592_clear_reg_mask(dev, R592_POWER, R592_POWER_20);
165 
166 	} else {
167 		dbg("switching to parallel mode");
168 
169 		/* This setting should be set _before_ switch TPC */
170 		r592_set_reg_mask(dev, R592_POWER, R592_POWER_20);
171 
172 		r592_clear_reg_mask(dev, R592_IO,
173 			R592_IO_SERIAL1 | R592_IO_SERIAL2);
174 
175 		/* Set the parallel mode now */
176 		r592_write_reg(dev, R592_IO_MODE, R592_IO_MODE_PARALLEL);
177 	}
178 
179 	dev->parallel_mode = parallel_mode;
180 	return 0;
181 }
182 
183 /* Perform a controller reset without powering down the card */
184 static void r592_host_reset(struct r592_device *dev)
185 {
186 	r592_set_reg_mask(dev, R592_IO, R592_IO_RESET);
187 	msleep(100);
188 	r592_set_mode(dev, dev->parallel_mode);
189 }
190 
191 #ifdef CONFIG_PM_SLEEP
192 /* Disable all hardware interrupts */
193 static void r592_clear_interrupts(struct r592_device *dev)
194 {
195 	/* Disable & ACK all interrupts */
196 	r592_clear_reg_mask(dev, R592_REG_MSC, IRQ_ALL_ACK_MASK);
197 	r592_clear_reg_mask(dev, R592_REG_MSC, IRQ_ALL_EN_MASK);
198 }
199 #endif
200 
201 /* Tests if there is an CRC error */
202 static int r592_test_io_error(struct r592_device *dev)
203 {
204 	if (!(r592_read_reg(dev, R592_STATUS) &
205 		(R592_STATUS_SEND_ERR | R592_STATUS_RECV_ERR)))
206 		return 0;
207 
208 	return -EIO;
209 }
210 
211 /* Ensure that FIFO is ready for use */
212 static int r592_test_fifo_empty(struct r592_device *dev)
213 {
214 	if (r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_FIFO_EMPTY)
215 		return 0;
216 
217 	dbg("FIFO not ready, trying to reset the device");
218 	r592_host_reset(dev);
219 
220 	if (r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_FIFO_EMPTY)
221 		return 0;
222 
223 	message("FIFO still not ready, giving up");
224 	return -EIO;
225 }
226 
227 /* Activates the DMA transfer from to FIFO */
228 static void r592_start_dma(struct r592_device *dev, bool is_write)
229 {
230 	unsigned long flags;
231 	u32 reg;
232 	spin_lock_irqsave(&dev->irq_lock, flags);
233 
234 	/* Ack interrupts (just in case) + enable them */
235 	r592_clear_reg_mask(dev, R592_REG_MSC, DMA_IRQ_ACK_MASK);
236 	r592_set_reg_mask(dev, R592_REG_MSC, DMA_IRQ_EN_MASK);
237 
238 	/* Set DMA address */
239 	r592_write_reg(dev, R592_FIFO_DMA, sg_dma_address(&dev->req->sg));
240 
241 	/* Enable the DMA */
242 	reg = r592_read_reg(dev, R592_FIFO_DMA_SETTINGS);
243 	reg |= R592_FIFO_DMA_SETTINGS_EN;
244 
245 	if (!is_write)
246 		reg |= R592_FIFO_DMA_SETTINGS_DIR;
247 	else
248 		reg &= ~R592_FIFO_DMA_SETTINGS_DIR;
249 	r592_write_reg(dev, R592_FIFO_DMA_SETTINGS, reg);
250 
251 	spin_unlock_irqrestore(&dev->irq_lock, flags);
252 }
253 
254 /* Cleanups DMA related settings */
255 static void r592_stop_dma(struct r592_device *dev, int error)
256 {
257 	r592_clear_reg_mask(dev, R592_FIFO_DMA_SETTINGS,
258 		R592_FIFO_DMA_SETTINGS_EN);
259 
260 	/* This is only a precation */
261 	r592_write_reg(dev, R592_FIFO_DMA,
262 			dev->dummy_dma_page_physical_address);
263 
264 	r592_clear_reg_mask(dev, R592_REG_MSC, DMA_IRQ_EN_MASK);
265 	r592_clear_reg_mask(dev, R592_REG_MSC, DMA_IRQ_ACK_MASK);
266 	dev->dma_error = error;
267 }
268 
269 /* Test if hardware supports DMA */
270 static void r592_check_dma(struct r592_device *dev)
271 {
272 	dev->dma_capable = r592_enable_dma &&
273 		(r592_read_reg(dev, R592_FIFO_DMA_SETTINGS) &
274 			R592_FIFO_DMA_SETTINGS_CAP);
275 }
276 
277 /* Transfers fifo contents in/out using DMA */
278 static int r592_transfer_fifo_dma(struct r592_device *dev)
279 {
280 	int len, sg_count;
281 	bool is_write;
282 
283 	if (!dev->dma_capable || !dev->req->long_data)
284 		return -EINVAL;
285 
286 	len = dev->req->sg.length;
287 	is_write = dev->req->data_dir == WRITE;
288 
289 	if (len != R592_LFIFO_SIZE)
290 		return -EINVAL;
291 
292 	dbg_verbose("doing dma transfer");
293 
294 	dev->dma_error = 0;
295 	reinit_completion(&dev->dma_done);
296 
297 	/* TODO: hidden assumption about nenth beeing always 1 */
298 	sg_count = dma_map_sg(&dev->pci_dev->dev, &dev->req->sg, 1, is_write ?
299 		PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
300 
301 	if (sg_count != 1 ||
302 			(sg_dma_len(&dev->req->sg) < dev->req->sg.length)) {
303 		message("problem in dma_map_sg");
304 		return -EIO;
305 	}
306 
307 	r592_start_dma(dev, is_write);
308 
309 	/* Wait for DMA completion */
310 	if (!wait_for_completion_timeout(
311 			&dev->dma_done, msecs_to_jiffies(1000))) {
312 		message("DMA timeout");
313 		r592_stop_dma(dev, -ETIMEDOUT);
314 	}
315 
316 	dma_unmap_sg(&dev->pci_dev->dev, &dev->req->sg, 1, is_write ?
317 		PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
318 
319 
320 	return dev->dma_error;
321 }
322 
323 /*
324  * Writes the FIFO in 4 byte chunks.
325  * If length isn't 4 byte aligned, rest of the data if put to a fifo
326  * to be written later
327  * Use r592_flush_fifo_write to flush that fifo when writing for the
328  * last time
329  */
330 static void r592_write_fifo_pio(struct r592_device *dev,
331 					unsigned char *buffer, int len)
332 {
333 	/* flush spill from former write */
334 	if (!kfifo_is_empty(&dev->pio_fifo)) {
335 
336 		u8 tmp[4] = {0};
337 		int copy_len = kfifo_in(&dev->pio_fifo, buffer, len);
338 
339 		if (!kfifo_is_full(&dev->pio_fifo))
340 			return;
341 		len -= copy_len;
342 		buffer += copy_len;
343 
344 		copy_len = kfifo_out(&dev->pio_fifo, tmp, 4);
345 		WARN_ON(copy_len != 4);
346 		r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)tmp);
347 	}
348 
349 	WARN_ON(!kfifo_is_empty(&dev->pio_fifo));
350 
351 	/* write full dwords */
352 	while (len >= 4) {
353 		r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)buffer);
354 		buffer += 4;
355 		len -= 4;
356 	}
357 
358 	/* put remaining bytes to the spill */
359 	if (len)
360 		kfifo_in(&dev->pio_fifo, buffer, len);
361 }
362 
363 /* Flushes the temporary FIFO used to make aligned DWORD writes */
364 static void r592_flush_fifo_write(struct r592_device *dev)
365 {
366 	u8 buffer[4] = { 0 };
367 	int len;
368 
369 	if (kfifo_is_empty(&dev->pio_fifo))
370 		return;
371 
372 	len = kfifo_out(&dev->pio_fifo, buffer, 4);
373 	r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)buffer);
374 }
375 
376 /*
377  * Read a fifo in 4 bytes chunks.
378  * If input doesn't fit the buffer, it places bytes of last dword in spill
379  * buffer, so that they don't get lost on last read, just throw these away.
380  */
381 static void r592_read_fifo_pio(struct r592_device *dev,
382 						unsigned char *buffer, int len)
383 {
384 	u8 tmp[4];
385 
386 	/* Read from last spill */
387 	if (!kfifo_is_empty(&dev->pio_fifo)) {
388 		int bytes_copied =
389 			kfifo_out(&dev->pio_fifo, buffer, min(4, len));
390 		buffer += bytes_copied;
391 		len -= bytes_copied;
392 
393 		if (!kfifo_is_empty(&dev->pio_fifo))
394 			return;
395 	}
396 
397 	/* Reads dwords from FIFO */
398 	while (len >= 4) {
399 		*(u32 *)buffer = r592_read_reg_raw_be(dev, R592_FIFO_PIO);
400 		buffer += 4;
401 		len -= 4;
402 	}
403 
404 	if (len) {
405 		*(u32 *)tmp = r592_read_reg_raw_be(dev, R592_FIFO_PIO);
406 		kfifo_in(&dev->pio_fifo, tmp, 4);
407 		len -= kfifo_out(&dev->pio_fifo, buffer, len);
408 	}
409 
410 	WARN_ON(len);
411 	return;
412 }
413 
414 /* Transfers actual data using PIO. */
415 static int r592_transfer_fifo_pio(struct r592_device *dev)
416 {
417 	unsigned long flags;
418 
419 	bool is_write = dev->req->tpc >= MS_TPC_SET_RW_REG_ADRS;
420 	struct sg_mapping_iter miter;
421 
422 	kfifo_reset(&dev->pio_fifo);
423 
424 	if (!dev->req->long_data) {
425 		if (is_write) {
426 			r592_write_fifo_pio(dev, dev->req->data,
427 							dev->req->data_len);
428 			r592_flush_fifo_write(dev);
429 		} else
430 			r592_read_fifo_pio(dev, dev->req->data,
431 							dev->req->data_len);
432 		return 0;
433 	}
434 
435 	local_irq_save(flags);
436 	sg_miter_start(&miter, &dev->req->sg, 1, SG_MITER_ATOMIC |
437 		(is_write ? SG_MITER_FROM_SG : SG_MITER_TO_SG));
438 
439 	/* Do the transfer fifo<->memory*/
440 	while (sg_miter_next(&miter))
441 		if (is_write)
442 			r592_write_fifo_pio(dev, miter.addr, miter.length);
443 		else
444 			r592_read_fifo_pio(dev, miter.addr, miter.length);
445 
446 
447 	/* Write last few non aligned bytes*/
448 	if (is_write)
449 		r592_flush_fifo_write(dev);
450 
451 	sg_miter_stop(&miter);
452 	local_irq_restore(flags);
453 	return 0;
454 }
455 
456 /* Executes one TPC (data is read/written from small or large fifo) */
457 static void r592_execute_tpc(struct r592_device *dev)
458 {
459 	bool is_write;
460 	int len, error;
461 	u32 status, reg;
462 
463 	if (!dev->req) {
464 		message("BUG: tpc execution without request!");
465 		return;
466 	}
467 
468 	is_write = dev->req->tpc >= MS_TPC_SET_RW_REG_ADRS;
469 	len = dev->req->long_data ?
470 		dev->req->sg.length : dev->req->data_len;
471 
472 	/* Ensure that FIFO can hold the input data */
473 	if (len > R592_LFIFO_SIZE) {
474 		message("IO: hardware doesn't support TPCs longer that 512");
475 		error = -ENOSYS;
476 		goto out;
477 	}
478 
479 	if (!(r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_PRSNT)) {
480 		dbg("IO: refusing to send TPC because card is absent");
481 		error = -ENODEV;
482 		goto out;
483 	}
484 
485 	dbg("IO: executing %s LEN=%d",
486 			memstick_debug_get_tpc_name(dev->req->tpc), len);
487 
488 	/* Set IO direction */
489 	if (is_write)
490 		r592_set_reg_mask(dev, R592_IO, R592_IO_DIRECTION);
491 	else
492 		r592_clear_reg_mask(dev, R592_IO, R592_IO_DIRECTION);
493 
494 
495 	error = r592_test_fifo_empty(dev);
496 	if (error)
497 		goto out;
498 
499 	/* Transfer write data */
500 	if (is_write) {
501 		error = r592_transfer_fifo_dma(dev);
502 		if (error == -EINVAL)
503 			error = r592_transfer_fifo_pio(dev);
504 	}
505 
506 	if (error)
507 		goto out;
508 
509 	/* Trigger the TPC */
510 	reg = (len << R592_TPC_EXEC_LEN_SHIFT) |
511 		(dev->req->tpc << R592_TPC_EXEC_TPC_SHIFT) |
512 			R592_TPC_EXEC_BIG_FIFO;
513 
514 	r592_write_reg(dev, R592_TPC_EXEC, reg);
515 
516 	/* Wait for TPC completion */
517 	status = R592_STATUS_RDY;
518 	if (dev->req->need_card_int)
519 		status |= R592_STATUS_CED;
520 
521 	error = r592_wait_status(dev, status, status);
522 	if (error) {
523 		message("card didn't respond");
524 		goto out;
525 	}
526 
527 	/* Test IO errors */
528 	error = r592_test_io_error(dev);
529 	if (error) {
530 		dbg("IO error");
531 		goto out;
532 	}
533 
534 	/* Read data from FIFO */
535 	if (!is_write) {
536 		error = r592_transfer_fifo_dma(dev);
537 		if (error == -EINVAL)
538 			error = r592_transfer_fifo_pio(dev);
539 	}
540 
541 	/* read INT reg. This can be shortened with shifts, but that way
542 		its more readable */
543 	if (dev->parallel_mode && dev->req->need_card_int) {
544 
545 		dev->req->int_reg = 0;
546 		status = r592_read_reg(dev, R592_STATUS);
547 
548 		if (status & R592_STATUS_P_CMDNACK)
549 			dev->req->int_reg |= MEMSTICK_INT_CMDNAK;
550 		if (status & R592_STATUS_P_BREQ)
551 			dev->req->int_reg |= MEMSTICK_INT_BREQ;
552 		if (status & R592_STATUS_P_INTERR)
553 			dev->req->int_reg |= MEMSTICK_INT_ERR;
554 		if (status & R592_STATUS_P_CED)
555 			dev->req->int_reg |= MEMSTICK_INT_CED;
556 	}
557 
558 	if (error)
559 		dbg("FIFO read error");
560 out:
561 	dev->req->error = error;
562 	r592_clear_reg_mask(dev, R592_REG_MSC, R592_REG_MSC_LED);
563 	return;
564 }
565 
566 /* Main request processing thread */
567 static int r592_process_thread(void *data)
568 {
569 	int error;
570 	struct r592_device *dev = (struct r592_device *)data;
571 	unsigned long flags;
572 
573 	while (!kthread_should_stop()) {
574 		spin_lock_irqsave(&dev->io_thread_lock, flags);
575 		set_current_state(TASK_INTERRUPTIBLE);
576 		error = memstick_next_req(dev->host, &dev->req);
577 		spin_unlock_irqrestore(&dev->io_thread_lock, flags);
578 
579 		if (error) {
580 			if (error == -ENXIO || error == -EAGAIN) {
581 				dbg_verbose("IO: done IO, sleeping");
582 			} else {
583 				dbg("IO: unknown error from "
584 					"memstick_next_req %d", error);
585 			}
586 
587 			if (kthread_should_stop())
588 				set_current_state(TASK_RUNNING);
589 
590 			schedule();
591 		} else {
592 			set_current_state(TASK_RUNNING);
593 			r592_execute_tpc(dev);
594 		}
595 	}
596 	return 0;
597 }
598 
599 /* Reprogram chip to detect change in card state */
600 /* eg, if card is detected, arm it to detect removal, and vice versa */
601 static void r592_update_card_detect(struct r592_device *dev)
602 {
603 	u32 reg = r592_read_reg(dev, R592_REG_MSC);
604 	bool card_detected = reg & R592_REG_MSC_PRSNT;
605 
606 	dbg("update card detect. card state: %s", card_detected ?
607 		"present" : "absent");
608 
609 	reg &= ~((R592_REG_MSC_IRQ_REMOVE | R592_REG_MSC_IRQ_INSERT) << 16);
610 
611 	if (card_detected)
612 		reg |= (R592_REG_MSC_IRQ_REMOVE << 16);
613 	else
614 		reg |= (R592_REG_MSC_IRQ_INSERT << 16);
615 
616 	r592_write_reg(dev, R592_REG_MSC, reg);
617 }
618 
619 /* Timer routine that fires 1 second after last card detection event, */
620 static void r592_detect_timer(long unsigned int data)
621 {
622 	struct r592_device *dev = (struct r592_device *)data;
623 	r592_update_card_detect(dev);
624 	memstick_detect_change(dev->host);
625 }
626 
627 /* Interrupt handler */
628 static irqreturn_t r592_irq(int irq, void *data)
629 {
630 	struct r592_device *dev = (struct r592_device *)data;
631 	irqreturn_t ret = IRQ_NONE;
632 	u32 reg;
633 	u16 irq_enable, irq_status;
634 	unsigned long flags;
635 	int error;
636 
637 	spin_lock_irqsave(&dev->irq_lock, flags);
638 
639 	reg = r592_read_reg(dev, R592_REG_MSC);
640 	irq_enable = reg >> 16;
641 	irq_status = reg & 0xFFFF;
642 
643 	/* Ack the interrupts */
644 	reg &= ~irq_status;
645 	r592_write_reg(dev, R592_REG_MSC, reg);
646 
647 	/* Get the IRQ status minus bits that aren't enabled */
648 	irq_status &= (irq_enable);
649 
650 	/* Due to limitation of memstick core, we don't look at bits that
651 		indicate that card was removed/inserted and/or present */
652 	if (irq_status & (R592_REG_MSC_IRQ_INSERT | R592_REG_MSC_IRQ_REMOVE)) {
653 
654 		bool card_was_added = irq_status & R592_REG_MSC_IRQ_INSERT;
655 		ret = IRQ_HANDLED;
656 
657 		message("IRQ: card %s", card_was_added ? "added" : "removed");
658 
659 		mod_timer(&dev->detect_timer,
660 			jiffies + msecs_to_jiffies(card_was_added ? 500 : 50));
661 	}
662 
663 	if (irq_status &
664 		(R592_REG_MSC_FIFO_DMA_DONE | R592_REG_MSC_FIFO_DMA_ERR)) {
665 		ret = IRQ_HANDLED;
666 
667 		if (irq_status & R592_REG_MSC_FIFO_DMA_ERR) {
668 			message("IRQ: DMA error");
669 			error = -EIO;
670 		} else {
671 			dbg_verbose("IRQ: dma done");
672 			error = 0;
673 		}
674 
675 		r592_stop_dma(dev, error);
676 		complete(&dev->dma_done);
677 	}
678 
679 	spin_unlock_irqrestore(&dev->irq_lock, flags);
680 	return ret;
681 }
682 
683 /* External inteface: set settings */
684 static int r592_set_param(struct memstick_host *host,
685 			enum memstick_param param, int value)
686 {
687 	struct r592_device *dev = memstick_priv(host);
688 
689 	switch (param) {
690 	case MEMSTICK_POWER:
691 		switch (value) {
692 		case MEMSTICK_POWER_ON:
693 			return r592_enable_device(dev, true);
694 		case MEMSTICK_POWER_OFF:
695 			return r592_enable_device(dev, false);
696 		default:
697 			return -EINVAL;
698 		}
699 	case MEMSTICK_INTERFACE:
700 		switch (value) {
701 		case MEMSTICK_SERIAL:
702 			return r592_set_mode(dev, 0);
703 		case MEMSTICK_PAR4:
704 			return r592_set_mode(dev, 1);
705 		default:
706 			return -EINVAL;
707 		}
708 	default:
709 		return -EINVAL;
710 	}
711 }
712 
713 /* External interface: submit requests */
714 static void r592_submit_req(struct memstick_host *host)
715 {
716 	struct r592_device *dev = memstick_priv(host);
717 	unsigned long flags;
718 
719 	if (dev->req)
720 		return;
721 
722 	spin_lock_irqsave(&dev->io_thread_lock, flags);
723 	if (wake_up_process(dev->io_thread))
724 		dbg_verbose("IO thread woken to process requests");
725 	spin_unlock_irqrestore(&dev->io_thread_lock, flags);
726 }
727 
728 static const struct pci_device_id r592_pci_id_tbl[] = {
729 
730 	{ PCI_VDEVICE(RICOH, 0x0592), },
731 	{ },
732 };
733 
734 /* Main entry */
735 static int r592_probe(struct pci_dev *pdev, const struct pci_device_id *id)
736 {
737 	int error = -ENOMEM;
738 	struct memstick_host *host;
739 	struct r592_device *dev;
740 
741 	/* Allocate memory */
742 	host = memstick_alloc_host(sizeof(struct r592_device), &pdev->dev);
743 	if (!host)
744 		goto error1;
745 
746 	dev = memstick_priv(host);
747 	dev->host = host;
748 	dev->pci_dev = pdev;
749 	pci_set_drvdata(pdev, dev);
750 
751 	/* pci initialization */
752 	error = pci_enable_device(pdev);
753 	if (error)
754 		goto error2;
755 
756 	pci_set_master(pdev);
757 	error = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
758 	if (error)
759 		goto error3;
760 
761 	error = pci_request_regions(pdev, DRV_NAME);
762 	if (error)
763 		goto error3;
764 
765 	dev->mmio = pci_ioremap_bar(pdev, 0);
766 	if (!dev->mmio)
767 		goto error4;
768 
769 	dev->irq = pdev->irq;
770 	spin_lock_init(&dev->irq_lock);
771 	spin_lock_init(&dev->io_thread_lock);
772 	init_completion(&dev->dma_done);
773 	INIT_KFIFO(dev->pio_fifo);
774 	setup_timer(&dev->detect_timer,
775 		r592_detect_timer, (long unsigned int)dev);
776 
777 	/* Host initialization */
778 	host->caps = MEMSTICK_CAP_PAR4;
779 	host->request = r592_submit_req;
780 	host->set_param = r592_set_param;
781 	r592_check_dma(dev);
782 
783 	dev->io_thread = kthread_run(r592_process_thread, dev, "r592_io");
784 	if (IS_ERR(dev->io_thread)) {
785 		error = PTR_ERR(dev->io_thread);
786 		goto error5;
787 	}
788 
789 	/* This is just a precation, so don't fail */
790 	dev->dummy_dma_page = pci_alloc_consistent(pdev, PAGE_SIZE,
791 		&dev->dummy_dma_page_physical_address);
792 	r592_stop_dma(dev , 0);
793 
794 	if (request_irq(dev->irq, &r592_irq, IRQF_SHARED,
795 			  DRV_NAME, dev))
796 		goto error6;
797 
798 	r592_update_card_detect(dev);
799 	if (memstick_add_host(host))
800 		goto error7;
801 
802 	message("driver successfully loaded");
803 	return 0;
804 error7:
805 	free_irq(dev->irq, dev);
806 error6:
807 	if (dev->dummy_dma_page)
808 		pci_free_consistent(pdev, PAGE_SIZE, dev->dummy_dma_page,
809 			dev->dummy_dma_page_physical_address);
810 
811 	kthread_stop(dev->io_thread);
812 error5:
813 	iounmap(dev->mmio);
814 error4:
815 	pci_release_regions(pdev);
816 error3:
817 	pci_disable_device(pdev);
818 error2:
819 	memstick_free_host(host);
820 error1:
821 	return error;
822 }
823 
824 static void r592_remove(struct pci_dev *pdev)
825 {
826 	int error = 0;
827 	struct r592_device *dev = pci_get_drvdata(pdev);
828 
829 	/* Stop the processing thread.
830 	That ensures that we won't take any more requests */
831 	kthread_stop(dev->io_thread);
832 
833 	r592_enable_device(dev, false);
834 
835 	while (!error && dev->req) {
836 		dev->req->error = -ETIME;
837 		error = memstick_next_req(dev->host, &dev->req);
838 	}
839 	memstick_remove_host(dev->host);
840 
841 	free_irq(dev->irq, dev);
842 	iounmap(dev->mmio);
843 	pci_release_regions(pdev);
844 	pci_disable_device(pdev);
845 	memstick_free_host(dev->host);
846 
847 	if (dev->dummy_dma_page)
848 		pci_free_consistent(pdev, PAGE_SIZE, dev->dummy_dma_page,
849 			dev->dummy_dma_page_physical_address);
850 }
851 
852 #ifdef CONFIG_PM_SLEEP
853 static int r592_suspend(struct device *core_dev)
854 {
855 	struct pci_dev *pdev = to_pci_dev(core_dev);
856 	struct r592_device *dev = pci_get_drvdata(pdev);
857 
858 	r592_clear_interrupts(dev);
859 	memstick_suspend_host(dev->host);
860 	del_timer_sync(&dev->detect_timer);
861 	return 0;
862 }
863 
864 static int r592_resume(struct device *core_dev)
865 {
866 	struct pci_dev *pdev = to_pci_dev(core_dev);
867 	struct r592_device *dev = pci_get_drvdata(pdev);
868 
869 	r592_clear_interrupts(dev);
870 	r592_enable_device(dev, false);
871 	memstick_resume_host(dev->host);
872 	r592_update_card_detect(dev);
873 	return 0;
874 }
875 #endif
876 
877 static SIMPLE_DEV_PM_OPS(r592_pm_ops, r592_suspend, r592_resume);
878 
879 MODULE_DEVICE_TABLE(pci, r592_pci_id_tbl);
880 
881 static struct pci_driver r852_pci_driver = {
882 	.name		= DRV_NAME,
883 	.id_table	= r592_pci_id_tbl,
884 	.probe		= r592_probe,
885 	.remove		= r592_remove,
886 	.driver.pm	= &r592_pm_ops,
887 };
888 
889 module_pci_driver(r852_pci_driver);
890 
891 module_param_named(enable_dma, r592_enable_dma, bool, S_IRUGO);
892 MODULE_PARM_DESC(enable_dma, "Enable usage of the DMA (default)");
893 module_param(debug, int, S_IRUGO | S_IWUSR);
894 MODULE_PARM_DESC(debug, "Debug level (0-3)");
895 
896 MODULE_LICENSE("GPL");
897 MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
898 MODULE_DESCRIPTION("Ricoh R5C592 Memstick/Memstick PRO card reader driver");
899