xref: /openbmc/linux/drivers/memstick/host/r592.c (revision 8730046c)
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 || sg_dma_len(&dev->req->sg) < R592_LFIFO_SIZE) {
302 		message("problem in dma_map_sg");
303 		return -EIO;
304 	}
305 
306 	r592_start_dma(dev, is_write);
307 
308 	/* Wait for DMA completion */
309 	if (!wait_for_completion_timeout(
310 			&dev->dma_done, msecs_to_jiffies(1000))) {
311 		message("DMA timeout");
312 		r592_stop_dma(dev, -ETIMEDOUT);
313 	}
314 
315 	dma_unmap_sg(&dev->pci_dev->dev, &dev->req->sg, 1, is_write ?
316 		PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
317 
318 
319 	return dev->dma_error;
320 }
321 
322 /*
323  * Writes the FIFO in 4 byte chunks.
324  * If length isn't 4 byte aligned, rest of the data if put to a fifo
325  * to be written later
326  * Use r592_flush_fifo_write to flush that fifo when writing for the
327  * last time
328  */
329 static void r592_write_fifo_pio(struct r592_device *dev,
330 					unsigned char *buffer, int len)
331 {
332 	/* flush spill from former write */
333 	if (!kfifo_is_empty(&dev->pio_fifo)) {
334 
335 		u8 tmp[4] = {0};
336 		int copy_len = kfifo_in(&dev->pio_fifo, buffer, len);
337 
338 		if (!kfifo_is_full(&dev->pio_fifo))
339 			return;
340 		len -= copy_len;
341 		buffer += copy_len;
342 
343 		copy_len = kfifo_out(&dev->pio_fifo, tmp, 4);
344 		WARN_ON(copy_len != 4);
345 		r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)tmp);
346 	}
347 
348 	WARN_ON(!kfifo_is_empty(&dev->pio_fifo));
349 
350 	/* write full dwords */
351 	while (len >= 4) {
352 		r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)buffer);
353 		buffer += 4;
354 		len -= 4;
355 	}
356 
357 	/* put remaining bytes to the spill */
358 	if (len)
359 		kfifo_in(&dev->pio_fifo, buffer, len);
360 }
361 
362 /* Flushes the temporary FIFO used to make aligned DWORD writes */
363 static void r592_flush_fifo_write(struct r592_device *dev)
364 {
365 	u8 buffer[4] = { 0 };
366 	int len;
367 
368 	if (kfifo_is_empty(&dev->pio_fifo))
369 		return;
370 
371 	len = kfifo_out(&dev->pio_fifo, buffer, 4);
372 	r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)buffer);
373 }
374 
375 /*
376  * Read a fifo in 4 bytes chunks.
377  * If input doesn't fit the buffer, it places bytes of last dword in spill
378  * buffer, so that they don't get lost on last read, just throw these away.
379  */
380 static void r592_read_fifo_pio(struct r592_device *dev,
381 						unsigned char *buffer, int len)
382 {
383 	u8 tmp[4];
384 
385 	/* Read from last spill */
386 	if (!kfifo_is_empty(&dev->pio_fifo)) {
387 		int bytes_copied =
388 			kfifo_out(&dev->pio_fifo, buffer, min(4, len));
389 		buffer += bytes_copied;
390 		len -= bytes_copied;
391 
392 		if (!kfifo_is_empty(&dev->pio_fifo))
393 			return;
394 	}
395 
396 	/* Reads dwords from FIFO */
397 	while (len >= 4) {
398 		*(u32 *)buffer = r592_read_reg_raw_be(dev, R592_FIFO_PIO);
399 		buffer += 4;
400 		len -= 4;
401 	}
402 
403 	if (len) {
404 		*(u32 *)tmp = r592_read_reg_raw_be(dev, R592_FIFO_PIO);
405 		kfifo_in(&dev->pio_fifo, tmp, 4);
406 		len -= kfifo_out(&dev->pio_fifo, buffer, len);
407 	}
408 
409 	WARN_ON(len);
410 	return;
411 }
412 
413 /* Transfers actual data using PIO. */
414 static int r592_transfer_fifo_pio(struct r592_device *dev)
415 {
416 	unsigned long flags;
417 
418 	bool is_write = dev->req->tpc >= MS_TPC_SET_RW_REG_ADRS;
419 	struct sg_mapping_iter miter;
420 
421 	kfifo_reset(&dev->pio_fifo);
422 
423 	if (!dev->req->long_data) {
424 		if (is_write) {
425 			r592_write_fifo_pio(dev, dev->req->data,
426 							dev->req->data_len);
427 			r592_flush_fifo_write(dev);
428 		} else
429 			r592_read_fifo_pio(dev, dev->req->data,
430 							dev->req->data_len);
431 		return 0;
432 	}
433 
434 	local_irq_save(flags);
435 	sg_miter_start(&miter, &dev->req->sg, 1, SG_MITER_ATOMIC |
436 		(is_write ? SG_MITER_FROM_SG : SG_MITER_TO_SG));
437 
438 	/* Do the transfer fifo<->memory*/
439 	while (sg_miter_next(&miter))
440 		if (is_write)
441 			r592_write_fifo_pio(dev, miter.addr, miter.length);
442 		else
443 			r592_read_fifo_pio(dev, miter.addr, miter.length);
444 
445 
446 	/* Write last few non aligned bytes*/
447 	if (is_write)
448 		r592_flush_fifo_write(dev);
449 
450 	sg_miter_stop(&miter);
451 	local_irq_restore(flags);
452 	return 0;
453 }
454 
455 /* Executes one TPC (data is read/written from small or large fifo) */
456 static void r592_execute_tpc(struct r592_device *dev)
457 {
458 	bool is_write;
459 	int len, error;
460 	u32 status, reg;
461 
462 	if (!dev->req) {
463 		message("BUG: tpc execution without request!");
464 		return;
465 	}
466 
467 	is_write = dev->req->tpc >= MS_TPC_SET_RW_REG_ADRS;
468 	len = dev->req->long_data ?
469 		dev->req->sg.length : dev->req->data_len;
470 
471 	/* Ensure that FIFO can hold the input data */
472 	if (len > R592_LFIFO_SIZE) {
473 		message("IO: hardware doesn't support TPCs longer that 512");
474 		error = -ENOSYS;
475 		goto out;
476 	}
477 
478 	if (!(r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_PRSNT)) {
479 		dbg("IO: refusing to send TPC because card is absent");
480 		error = -ENODEV;
481 		goto out;
482 	}
483 
484 	dbg("IO: executing %s LEN=%d",
485 			memstick_debug_get_tpc_name(dev->req->tpc), len);
486 
487 	/* Set IO direction */
488 	if (is_write)
489 		r592_set_reg_mask(dev, R592_IO, R592_IO_DIRECTION);
490 	else
491 		r592_clear_reg_mask(dev, R592_IO, R592_IO_DIRECTION);
492 
493 
494 	error = r592_test_fifo_empty(dev);
495 	if (error)
496 		goto out;
497 
498 	/* Transfer write data */
499 	if (is_write) {
500 		error = r592_transfer_fifo_dma(dev);
501 		if (error == -EINVAL)
502 			error = r592_transfer_fifo_pio(dev);
503 	}
504 
505 	if (error)
506 		goto out;
507 
508 	/* Trigger the TPC */
509 	reg = (len << R592_TPC_EXEC_LEN_SHIFT) |
510 		(dev->req->tpc << R592_TPC_EXEC_TPC_SHIFT) |
511 			R592_TPC_EXEC_BIG_FIFO;
512 
513 	r592_write_reg(dev, R592_TPC_EXEC, reg);
514 
515 	/* Wait for TPC completion */
516 	status = R592_STATUS_RDY;
517 	if (dev->req->need_card_int)
518 		status |= R592_STATUS_CED;
519 
520 	error = r592_wait_status(dev, status, status);
521 	if (error) {
522 		message("card didn't respond");
523 		goto out;
524 	}
525 
526 	/* Test IO errors */
527 	error = r592_test_io_error(dev);
528 	if (error) {
529 		dbg("IO error");
530 		goto out;
531 	}
532 
533 	/* Read data from FIFO */
534 	if (!is_write) {
535 		error = r592_transfer_fifo_dma(dev);
536 		if (error == -EINVAL)
537 			error = r592_transfer_fifo_pio(dev);
538 	}
539 
540 	/* read INT reg. This can be shortened with shifts, but that way
541 		its more readable */
542 	if (dev->parallel_mode && dev->req->need_card_int) {
543 
544 		dev->req->int_reg = 0;
545 		status = r592_read_reg(dev, R592_STATUS);
546 
547 		if (status & R592_STATUS_P_CMDNACK)
548 			dev->req->int_reg |= MEMSTICK_INT_CMDNAK;
549 		if (status & R592_STATUS_P_BREQ)
550 			dev->req->int_reg |= MEMSTICK_INT_BREQ;
551 		if (status & R592_STATUS_P_INTERR)
552 			dev->req->int_reg |= MEMSTICK_INT_ERR;
553 		if (status & R592_STATUS_P_CED)
554 			dev->req->int_reg |= MEMSTICK_INT_CED;
555 	}
556 
557 	if (error)
558 		dbg("FIFO read error");
559 out:
560 	dev->req->error = error;
561 	r592_clear_reg_mask(dev, R592_REG_MSC, R592_REG_MSC_LED);
562 	return;
563 }
564 
565 /* Main request processing thread */
566 static int r592_process_thread(void *data)
567 {
568 	int error;
569 	struct r592_device *dev = (struct r592_device *)data;
570 	unsigned long flags;
571 
572 	while (!kthread_should_stop()) {
573 		spin_lock_irqsave(&dev->io_thread_lock, flags);
574 		set_current_state(TASK_INTERRUPTIBLE);
575 		error = memstick_next_req(dev->host, &dev->req);
576 		spin_unlock_irqrestore(&dev->io_thread_lock, flags);
577 
578 		if (error) {
579 			if (error == -ENXIO || error == -EAGAIN) {
580 				dbg_verbose("IO: done IO, sleeping");
581 			} else {
582 				dbg("IO: unknown error from "
583 					"memstick_next_req %d", error);
584 			}
585 
586 			if (kthread_should_stop())
587 				set_current_state(TASK_RUNNING);
588 
589 			schedule();
590 		} else {
591 			set_current_state(TASK_RUNNING);
592 			r592_execute_tpc(dev);
593 		}
594 	}
595 	return 0;
596 }
597 
598 /* Reprogram chip to detect change in card state */
599 /* eg, if card is detected, arm it to detect removal, and vice versa */
600 static void r592_update_card_detect(struct r592_device *dev)
601 {
602 	u32 reg = r592_read_reg(dev, R592_REG_MSC);
603 	bool card_detected = reg & R592_REG_MSC_PRSNT;
604 
605 	dbg("update card detect. card state: %s", card_detected ?
606 		"present" : "absent");
607 
608 	reg &= ~((R592_REG_MSC_IRQ_REMOVE | R592_REG_MSC_IRQ_INSERT) << 16);
609 
610 	if (card_detected)
611 		reg |= (R592_REG_MSC_IRQ_REMOVE << 16);
612 	else
613 		reg |= (R592_REG_MSC_IRQ_INSERT << 16);
614 
615 	r592_write_reg(dev, R592_REG_MSC, reg);
616 }
617 
618 /* Timer routine that fires 1 second after last card detection event, */
619 static void r592_detect_timer(long unsigned int data)
620 {
621 	struct r592_device *dev = (struct r592_device *)data;
622 	r592_update_card_detect(dev);
623 	memstick_detect_change(dev->host);
624 }
625 
626 /* Interrupt handler */
627 static irqreturn_t r592_irq(int irq, void *data)
628 {
629 	struct r592_device *dev = (struct r592_device *)data;
630 	irqreturn_t ret = IRQ_NONE;
631 	u32 reg;
632 	u16 irq_enable, irq_status;
633 	unsigned long flags;
634 	int error;
635 
636 	spin_lock_irqsave(&dev->irq_lock, flags);
637 
638 	reg = r592_read_reg(dev, R592_REG_MSC);
639 	irq_enable = reg >> 16;
640 	irq_status = reg & 0xFFFF;
641 
642 	/* Ack the interrupts */
643 	reg &= ~irq_status;
644 	r592_write_reg(dev, R592_REG_MSC, reg);
645 
646 	/* Get the IRQ status minus bits that aren't enabled */
647 	irq_status &= (irq_enable);
648 
649 	/* Due to limitation of memstick core, we don't look at bits that
650 		indicate that card was removed/inserted and/or present */
651 	if (irq_status & (R592_REG_MSC_IRQ_INSERT | R592_REG_MSC_IRQ_REMOVE)) {
652 
653 		bool card_was_added = irq_status & R592_REG_MSC_IRQ_INSERT;
654 		ret = IRQ_HANDLED;
655 
656 		message("IRQ: card %s", card_was_added ? "added" : "removed");
657 
658 		mod_timer(&dev->detect_timer,
659 			jiffies + msecs_to_jiffies(card_was_added ? 500 : 50));
660 	}
661 
662 	if (irq_status &
663 		(R592_REG_MSC_FIFO_DMA_DONE | R592_REG_MSC_FIFO_DMA_ERR)) {
664 		ret = IRQ_HANDLED;
665 
666 		if (irq_status & R592_REG_MSC_FIFO_DMA_ERR) {
667 			message("IRQ: DMA error");
668 			error = -EIO;
669 		} else {
670 			dbg_verbose("IRQ: dma done");
671 			error = 0;
672 		}
673 
674 		r592_stop_dma(dev, error);
675 		complete(&dev->dma_done);
676 	}
677 
678 	spin_unlock_irqrestore(&dev->irq_lock, flags);
679 	return ret;
680 }
681 
682 /* External inteface: set settings */
683 static int r592_set_param(struct memstick_host *host,
684 			enum memstick_param param, int value)
685 {
686 	struct r592_device *dev = memstick_priv(host);
687 
688 	switch (param) {
689 	case MEMSTICK_POWER:
690 		switch (value) {
691 		case MEMSTICK_POWER_ON:
692 			return r592_enable_device(dev, true);
693 		case MEMSTICK_POWER_OFF:
694 			return r592_enable_device(dev, false);
695 		default:
696 			return -EINVAL;
697 		}
698 	case MEMSTICK_INTERFACE:
699 		switch (value) {
700 		case MEMSTICK_SERIAL:
701 			return r592_set_mode(dev, 0);
702 		case MEMSTICK_PAR4:
703 			return r592_set_mode(dev, 1);
704 		default:
705 			return -EINVAL;
706 		}
707 	default:
708 		return -EINVAL;
709 	}
710 }
711 
712 /* External interface: submit requests */
713 static void r592_submit_req(struct memstick_host *host)
714 {
715 	struct r592_device *dev = memstick_priv(host);
716 	unsigned long flags;
717 
718 	if (dev->req)
719 		return;
720 
721 	spin_lock_irqsave(&dev->io_thread_lock, flags);
722 	if (wake_up_process(dev->io_thread))
723 		dbg_verbose("IO thread woken to process requests");
724 	spin_unlock_irqrestore(&dev->io_thread_lock, flags);
725 }
726 
727 static const struct pci_device_id r592_pci_id_tbl[] = {
728 
729 	{ PCI_VDEVICE(RICOH, 0x0592), },
730 	{ },
731 };
732 
733 /* Main entry */
734 static int r592_probe(struct pci_dev *pdev, const struct pci_device_id *id)
735 {
736 	int error = -ENOMEM;
737 	struct memstick_host *host;
738 	struct r592_device *dev;
739 
740 	/* Allocate memory */
741 	host = memstick_alloc_host(sizeof(struct r592_device), &pdev->dev);
742 	if (!host)
743 		goto error1;
744 
745 	dev = memstick_priv(host);
746 	dev->host = host;
747 	dev->pci_dev = pdev;
748 	pci_set_drvdata(pdev, dev);
749 
750 	/* pci initialization */
751 	error = pci_enable_device(pdev);
752 	if (error)
753 		goto error2;
754 
755 	pci_set_master(pdev);
756 	error = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
757 	if (error)
758 		goto error3;
759 
760 	error = pci_request_regions(pdev, DRV_NAME);
761 	if (error)
762 		goto error3;
763 
764 	dev->mmio = pci_ioremap_bar(pdev, 0);
765 	if (!dev->mmio)
766 		goto error4;
767 
768 	dev->irq = pdev->irq;
769 	spin_lock_init(&dev->irq_lock);
770 	spin_lock_init(&dev->io_thread_lock);
771 	init_completion(&dev->dma_done);
772 	INIT_KFIFO(dev->pio_fifo);
773 	setup_timer(&dev->detect_timer,
774 		r592_detect_timer, (long unsigned int)dev);
775 
776 	/* Host initialization */
777 	host->caps = MEMSTICK_CAP_PAR4;
778 	host->request = r592_submit_req;
779 	host->set_param = r592_set_param;
780 	r592_check_dma(dev);
781 
782 	dev->io_thread = kthread_run(r592_process_thread, dev, "r592_io");
783 	if (IS_ERR(dev->io_thread)) {
784 		error = PTR_ERR(dev->io_thread);
785 		goto error5;
786 	}
787 
788 	/* This is just a precation, so don't fail */
789 	dev->dummy_dma_page = dma_alloc_coherent(&pdev->dev, PAGE_SIZE,
790 		&dev->dummy_dma_page_physical_address, GFP_KERNEL);
791 	r592_stop_dma(dev , 0);
792 
793 	if (request_irq(dev->irq, &r592_irq, IRQF_SHARED,
794 			  DRV_NAME, dev))
795 		goto error6;
796 
797 	r592_update_card_detect(dev);
798 	if (memstick_add_host(host))
799 		goto error7;
800 
801 	message("driver successfully loaded");
802 	return 0;
803 error7:
804 	free_irq(dev->irq, dev);
805 error6:
806 	if (dev->dummy_dma_page)
807 		dma_free_coherent(&pdev->dev, PAGE_SIZE, dev->dummy_dma_page,
808 			dev->dummy_dma_page_physical_address);
809 
810 	kthread_stop(dev->io_thread);
811 error5:
812 	iounmap(dev->mmio);
813 error4:
814 	pci_release_regions(pdev);
815 error3:
816 	pci_disable_device(pdev);
817 error2:
818 	memstick_free_host(host);
819 error1:
820 	return error;
821 }
822 
823 static void r592_remove(struct pci_dev *pdev)
824 {
825 	int error = 0;
826 	struct r592_device *dev = pci_get_drvdata(pdev);
827 
828 	/* Stop the processing thread.
829 	That ensures that we won't take any more requests */
830 	kthread_stop(dev->io_thread);
831 
832 	r592_enable_device(dev, false);
833 
834 	while (!error && dev->req) {
835 		dev->req->error = -ETIME;
836 		error = memstick_next_req(dev->host, &dev->req);
837 	}
838 	memstick_remove_host(dev->host);
839 
840 	free_irq(dev->irq, dev);
841 	iounmap(dev->mmio);
842 	pci_release_regions(pdev);
843 	pci_disable_device(pdev);
844 	memstick_free_host(dev->host);
845 
846 	if (dev->dummy_dma_page)
847 		dma_free_coherent(&pdev->dev, PAGE_SIZE, dev->dummy_dma_page,
848 			dev->dummy_dma_page_physical_address);
849 }
850 
851 #ifdef CONFIG_PM_SLEEP
852 static int r592_suspend(struct device *core_dev)
853 {
854 	struct pci_dev *pdev = to_pci_dev(core_dev);
855 	struct r592_device *dev = pci_get_drvdata(pdev);
856 
857 	r592_clear_interrupts(dev);
858 	memstick_suspend_host(dev->host);
859 	del_timer_sync(&dev->detect_timer);
860 	return 0;
861 }
862 
863 static int r592_resume(struct device *core_dev)
864 {
865 	struct pci_dev *pdev = to_pci_dev(core_dev);
866 	struct r592_device *dev = pci_get_drvdata(pdev);
867 
868 	r592_clear_interrupts(dev);
869 	r592_enable_device(dev, false);
870 	memstick_resume_host(dev->host);
871 	r592_update_card_detect(dev);
872 	return 0;
873 }
874 #endif
875 
876 static SIMPLE_DEV_PM_OPS(r592_pm_ops, r592_suspend, r592_resume);
877 
878 MODULE_DEVICE_TABLE(pci, r592_pci_id_tbl);
879 
880 static struct pci_driver r852_pci_driver = {
881 	.name		= DRV_NAME,
882 	.id_table	= r592_pci_id_tbl,
883 	.probe		= r592_probe,
884 	.remove		= r592_remove,
885 	.driver.pm	= &r592_pm_ops,
886 };
887 
888 module_pci_driver(r852_pci_driver);
889 
890 module_param_named(enable_dma, r592_enable_dma, bool, S_IRUGO);
891 MODULE_PARM_DESC(enable_dma, "Enable usage of the DMA (default)");
892 module_param(debug, int, S_IRUGO | S_IWUSR);
893 MODULE_PARM_DESC(debug, "Debug level (0-3)");
894 
895 MODULE_LICENSE("GPL");
896 MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
897 MODULE_DESCRIPTION("Ricoh R5C592 Memstick/Memstick PRO card reader driver");
898