xref: /openbmc/linux/drivers/memstick/host/r592.c (revision 4e5e4705)
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 /* Disable all hardware interrupts */
192 static void r592_clear_interrupts(struct r592_device *dev)
193 {
194 	/* Disable & ACK all interrupts */
195 	r592_clear_reg_mask(dev, R592_REG_MSC, IRQ_ALL_ACK_MASK);
196 	r592_clear_reg_mask(dev, R592_REG_MSC, IRQ_ALL_EN_MASK);
197 }
198 
199 /* Tests if there is an CRC error */
200 static int r592_test_io_error(struct r592_device *dev)
201 {
202 	if (!(r592_read_reg(dev, R592_STATUS) &
203 		(R592_STATUS_SEND_ERR | R592_STATUS_RECV_ERR)))
204 		return 0;
205 
206 	return -EIO;
207 }
208 
209 /* Ensure that FIFO is ready for use */
210 static int r592_test_fifo_empty(struct r592_device *dev)
211 {
212 	if (r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_FIFO_EMPTY)
213 		return 0;
214 
215 	dbg("FIFO not ready, trying to reset the device");
216 	r592_host_reset(dev);
217 
218 	if (r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_FIFO_EMPTY)
219 		return 0;
220 
221 	message("FIFO still not ready, giving up");
222 	return -EIO;
223 }
224 
225 /* Activates the DMA transfer from to FIFO */
226 static void r592_start_dma(struct r592_device *dev, bool is_write)
227 {
228 	unsigned long flags;
229 	u32 reg;
230 	spin_lock_irqsave(&dev->irq_lock, flags);
231 
232 	/* Ack interrupts (just in case) + enable them */
233 	r592_clear_reg_mask(dev, R592_REG_MSC, DMA_IRQ_ACK_MASK);
234 	r592_set_reg_mask(dev, R592_REG_MSC, DMA_IRQ_EN_MASK);
235 
236 	/* Set DMA address */
237 	r592_write_reg(dev, R592_FIFO_DMA, sg_dma_address(&dev->req->sg));
238 
239 	/* Enable the DMA */
240 	reg = r592_read_reg(dev, R592_FIFO_DMA_SETTINGS);
241 	reg |= R592_FIFO_DMA_SETTINGS_EN;
242 
243 	if (!is_write)
244 		reg |= R592_FIFO_DMA_SETTINGS_DIR;
245 	else
246 		reg &= ~R592_FIFO_DMA_SETTINGS_DIR;
247 	r592_write_reg(dev, R592_FIFO_DMA_SETTINGS, reg);
248 
249 	spin_unlock_irqrestore(&dev->irq_lock, flags);
250 }
251 
252 /* Cleanups DMA related settings */
253 static void r592_stop_dma(struct r592_device *dev, int error)
254 {
255 	r592_clear_reg_mask(dev, R592_FIFO_DMA_SETTINGS,
256 		R592_FIFO_DMA_SETTINGS_EN);
257 
258 	/* This is only a precation */
259 	r592_write_reg(dev, R592_FIFO_DMA,
260 			dev->dummy_dma_page_physical_address);
261 
262 	r592_clear_reg_mask(dev, R592_REG_MSC, DMA_IRQ_EN_MASK);
263 	r592_clear_reg_mask(dev, R592_REG_MSC, DMA_IRQ_ACK_MASK);
264 	dev->dma_error = error;
265 }
266 
267 /* Test if hardware supports DMA */
268 static void r592_check_dma(struct r592_device *dev)
269 {
270 	dev->dma_capable = r592_enable_dma &&
271 		(r592_read_reg(dev, R592_FIFO_DMA_SETTINGS) &
272 			R592_FIFO_DMA_SETTINGS_CAP);
273 }
274 
275 /* Transfers fifo contents in/out using DMA */
276 static int r592_transfer_fifo_dma(struct r592_device *dev)
277 {
278 	int len, sg_count;
279 	bool is_write;
280 
281 	if (!dev->dma_capable || !dev->req->long_data)
282 		return -EINVAL;
283 
284 	len = dev->req->sg.length;
285 	is_write = dev->req->data_dir == WRITE;
286 
287 	if (len != R592_LFIFO_SIZE)
288 		return -EINVAL;
289 
290 	dbg_verbose("doing dma transfer");
291 
292 	dev->dma_error = 0;
293 	reinit_completion(&dev->dma_done);
294 
295 	/* TODO: hidden assumption about nenth beeing always 1 */
296 	sg_count = dma_map_sg(&dev->pci_dev->dev, &dev->req->sg, 1, is_write ?
297 		PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
298 
299 	if (sg_count != 1 ||
300 			(sg_dma_len(&dev->req->sg) < dev->req->sg.length)) {
301 		message("problem in dma_map_sg");
302 		return -EIO;
303 	}
304 
305 	r592_start_dma(dev, is_write);
306 
307 	/* Wait for DMA completion */
308 	if (!wait_for_completion_timeout(
309 			&dev->dma_done, msecs_to_jiffies(1000))) {
310 		message("DMA timeout");
311 		r592_stop_dma(dev, -ETIMEDOUT);
312 	}
313 
314 	dma_unmap_sg(&dev->pci_dev->dev, &dev->req->sg, 1, is_write ?
315 		PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
316 
317 
318 	return dev->dma_error;
319 }
320 
321 /*
322  * Writes the FIFO in 4 byte chunks.
323  * If length isn't 4 byte aligned, rest of the data if put to a fifo
324  * to be written later
325  * Use r592_flush_fifo_write to flush that fifo when writing for the
326  * last time
327  */
328 static void r592_write_fifo_pio(struct r592_device *dev,
329 					unsigned char *buffer, int len)
330 {
331 	/* flush spill from former write */
332 	if (!kfifo_is_empty(&dev->pio_fifo)) {
333 
334 		u8 tmp[4] = {0};
335 		int copy_len = kfifo_in(&dev->pio_fifo, buffer, len);
336 
337 		if (!kfifo_is_full(&dev->pio_fifo))
338 			return;
339 		len -= copy_len;
340 		buffer += copy_len;
341 
342 		copy_len = kfifo_out(&dev->pio_fifo, tmp, 4);
343 		WARN_ON(copy_len != 4);
344 		r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)tmp);
345 	}
346 
347 	WARN_ON(!kfifo_is_empty(&dev->pio_fifo));
348 
349 	/* write full dwords */
350 	while (len >= 4) {
351 		r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)buffer);
352 		buffer += 4;
353 		len -= 4;
354 	}
355 
356 	/* put remaining bytes to the spill */
357 	if (len)
358 		kfifo_in(&dev->pio_fifo, buffer, len);
359 }
360 
361 /* Flushes the temporary FIFO used to make aligned DWORD writes */
362 static void r592_flush_fifo_write(struct r592_device *dev)
363 {
364 	u8 buffer[4] = { 0 };
365 	int len;
366 
367 	if (kfifo_is_empty(&dev->pio_fifo))
368 		return;
369 
370 	len = kfifo_out(&dev->pio_fifo, buffer, 4);
371 	r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)buffer);
372 }
373 
374 /*
375  * Read a fifo in 4 bytes chunks.
376  * If input doesn't fit the buffer, it places bytes of last dword in spill
377  * buffer, so that they don't get lost on last read, just throw these away.
378  */
379 static void r592_read_fifo_pio(struct r592_device *dev,
380 						unsigned char *buffer, int len)
381 {
382 	u8 tmp[4];
383 
384 	/* Read from last spill */
385 	if (!kfifo_is_empty(&dev->pio_fifo)) {
386 		int bytes_copied =
387 			kfifo_out(&dev->pio_fifo, buffer, min(4, len));
388 		buffer += bytes_copied;
389 		len -= bytes_copied;
390 
391 		if (!kfifo_is_empty(&dev->pio_fifo))
392 			return;
393 	}
394 
395 	/* Reads dwords from FIFO */
396 	while (len >= 4) {
397 		*(u32 *)buffer = r592_read_reg_raw_be(dev, R592_FIFO_PIO);
398 		buffer += 4;
399 		len -= 4;
400 	}
401 
402 	if (len) {
403 		*(u32 *)tmp = r592_read_reg_raw_be(dev, R592_FIFO_PIO);
404 		kfifo_in(&dev->pio_fifo, tmp, 4);
405 		len -= kfifo_out(&dev->pio_fifo, buffer, len);
406 	}
407 
408 	WARN_ON(len);
409 	return;
410 }
411 
412 /* Transfers actual data using PIO. */
413 static int r592_transfer_fifo_pio(struct r592_device *dev)
414 {
415 	unsigned long flags;
416 
417 	bool is_write = dev->req->tpc >= MS_TPC_SET_RW_REG_ADRS;
418 	struct sg_mapping_iter miter;
419 
420 	kfifo_reset(&dev->pio_fifo);
421 
422 	if (!dev->req->long_data) {
423 		if (is_write) {
424 			r592_write_fifo_pio(dev, dev->req->data,
425 							dev->req->data_len);
426 			r592_flush_fifo_write(dev);
427 		} else
428 			r592_read_fifo_pio(dev, dev->req->data,
429 							dev->req->data_len);
430 		return 0;
431 	}
432 
433 	local_irq_save(flags);
434 	sg_miter_start(&miter, &dev->req->sg, 1, SG_MITER_ATOMIC |
435 		(is_write ? SG_MITER_FROM_SG : SG_MITER_TO_SG));
436 
437 	/* Do the transfer fifo<->memory*/
438 	while (sg_miter_next(&miter))
439 		if (is_write)
440 			r592_write_fifo_pio(dev, miter.addr, miter.length);
441 		else
442 			r592_read_fifo_pio(dev, miter.addr, miter.length);
443 
444 
445 	/* Write last few non aligned bytes*/
446 	if (is_write)
447 		r592_flush_fifo_write(dev);
448 
449 	sg_miter_stop(&miter);
450 	local_irq_restore(flags);
451 	return 0;
452 }
453 
454 /* Executes one TPC (data is read/written from small or large fifo) */
455 static void r592_execute_tpc(struct r592_device *dev)
456 {
457 	bool is_write;
458 	int len, error;
459 	u32 status, reg;
460 
461 	if (!dev->req) {
462 		message("BUG: tpc execution without request!");
463 		return;
464 	}
465 
466 	is_write = dev->req->tpc >= MS_TPC_SET_RW_REG_ADRS;
467 	len = dev->req->long_data ?
468 		dev->req->sg.length : dev->req->data_len;
469 
470 	/* Ensure that FIFO can hold the input data */
471 	if (len > R592_LFIFO_SIZE) {
472 		message("IO: hardware doesn't support TPCs longer that 512");
473 		error = -ENOSYS;
474 		goto out;
475 	}
476 
477 	if (!(r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_PRSNT)) {
478 		dbg("IO: refusing to send TPC because card is absent");
479 		error = -ENODEV;
480 		goto out;
481 	}
482 
483 	dbg("IO: executing %s LEN=%d",
484 			memstick_debug_get_tpc_name(dev->req->tpc), len);
485 
486 	/* Set IO direction */
487 	if (is_write)
488 		r592_set_reg_mask(dev, R592_IO, R592_IO_DIRECTION);
489 	else
490 		r592_clear_reg_mask(dev, R592_IO, R592_IO_DIRECTION);
491 
492 
493 	error = r592_test_fifo_empty(dev);
494 	if (error)
495 		goto out;
496 
497 	/* Transfer write data */
498 	if (is_write) {
499 		error = r592_transfer_fifo_dma(dev);
500 		if (error == -EINVAL)
501 			error = r592_transfer_fifo_pio(dev);
502 	}
503 
504 	if (error)
505 		goto out;
506 
507 	/* Trigger the TPC */
508 	reg = (len << R592_TPC_EXEC_LEN_SHIFT) |
509 		(dev->req->tpc << R592_TPC_EXEC_TPC_SHIFT) |
510 			R592_TPC_EXEC_BIG_FIFO;
511 
512 	r592_write_reg(dev, R592_TPC_EXEC, reg);
513 
514 	/* Wait for TPC completion */
515 	status = R592_STATUS_RDY;
516 	if (dev->req->need_card_int)
517 		status |= R592_STATUS_CED;
518 
519 	error = r592_wait_status(dev, status, status);
520 	if (error) {
521 		message("card didn't respond");
522 		goto out;
523 	}
524 
525 	/* Test IO errors */
526 	error = r592_test_io_error(dev);
527 	if (error) {
528 		dbg("IO error");
529 		goto out;
530 	}
531 
532 	/* Read data from FIFO */
533 	if (!is_write) {
534 		error = r592_transfer_fifo_dma(dev);
535 		if (error == -EINVAL)
536 			error = r592_transfer_fifo_pio(dev);
537 	}
538 
539 	/* read INT reg. This can be shortened with shifts, but that way
540 		its more readable */
541 	if (dev->parallel_mode && dev->req->need_card_int) {
542 
543 		dev->req->int_reg = 0;
544 		status = r592_read_reg(dev, R592_STATUS);
545 
546 		if (status & R592_STATUS_P_CMDNACK)
547 			dev->req->int_reg |= MEMSTICK_INT_CMDNAK;
548 		if (status & R592_STATUS_P_BREQ)
549 			dev->req->int_reg |= MEMSTICK_INT_BREQ;
550 		if (status & R592_STATUS_P_INTERR)
551 			dev->req->int_reg |= MEMSTICK_INT_ERR;
552 		if (status & R592_STATUS_P_CED)
553 			dev->req->int_reg |= MEMSTICK_INT_CED;
554 	}
555 
556 	if (error)
557 		dbg("FIFO read error");
558 out:
559 	dev->req->error = error;
560 	r592_clear_reg_mask(dev, R592_REG_MSC, R592_REG_MSC_LED);
561 	return;
562 }
563 
564 /* Main request processing thread */
565 static int r592_process_thread(void *data)
566 {
567 	int error;
568 	struct r592_device *dev = (struct r592_device *)data;
569 	unsigned long flags;
570 
571 	while (!kthread_should_stop()) {
572 		spin_lock_irqsave(&dev->io_thread_lock, flags);
573 		set_current_state(TASK_INTERRUPTIBLE);
574 		error = memstick_next_req(dev->host, &dev->req);
575 		spin_unlock_irqrestore(&dev->io_thread_lock, flags);
576 
577 		if (error) {
578 			if (error == -ENXIO || error == -EAGAIN) {
579 				dbg_verbose("IO: done IO, sleeping");
580 			} else {
581 				dbg("IO: unknown error from "
582 					"memstick_next_req %d", error);
583 			}
584 
585 			if (kthread_should_stop())
586 				set_current_state(TASK_RUNNING);
587 
588 			schedule();
589 		} else {
590 			set_current_state(TASK_RUNNING);
591 			r592_execute_tpc(dev);
592 		}
593 	}
594 	return 0;
595 }
596 
597 /* Reprogram chip to detect change in card state */
598 /* eg, if card is detected, arm it to detect removal, and vice versa */
599 static void r592_update_card_detect(struct r592_device *dev)
600 {
601 	u32 reg = r592_read_reg(dev, R592_REG_MSC);
602 	bool card_detected = reg & R592_REG_MSC_PRSNT;
603 
604 	dbg("update card detect. card state: %s", card_detected ?
605 		"present" : "absent");
606 
607 	reg &= ~((R592_REG_MSC_IRQ_REMOVE | R592_REG_MSC_IRQ_INSERT) << 16);
608 
609 	if (card_detected)
610 		reg |= (R592_REG_MSC_IRQ_REMOVE << 16);
611 	else
612 		reg |= (R592_REG_MSC_IRQ_INSERT << 16);
613 
614 	r592_write_reg(dev, R592_REG_MSC, reg);
615 }
616 
617 /* Timer routine that fires 1 second after last card detection event, */
618 static void r592_detect_timer(long unsigned int data)
619 {
620 	struct r592_device *dev = (struct r592_device *)data;
621 	r592_update_card_detect(dev);
622 	memstick_detect_change(dev->host);
623 }
624 
625 /* Interrupt handler */
626 static irqreturn_t r592_irq(int irq, void *data)
627 {
628 	struct r592_device *dev = (struct r592_device *)data;
629 	irqreturn_t ret = IRQ_NONE;
630 	u32 reg;
631 	u16 irq_enable, irq_status;
632 	unsigned long flags;
633 	int error;
634 
635 	spin_lock_irqsave(&dev->irq_lock, flags);
636 
637 	reg = r592_read_reg(dev, R592_REG_MSC);
638 	irq_enable = reg >> 16;
639 	irq_status = reg & 0xFFFF;
640 
641 	/* Ack the interrupts */
642 	reg &= ~irq_status;
643 	r592_write_reg(dev, R592_REG_MSC, reg);
644 
645 	/* Get the IRQ status minus bits that aren't enabled */
646 	irq_status &= (irq_enable);
647 
648 	/* Due to limitation of memstick core, we don't look at bits that
649 		indicate that card was removed/inserted and/or present */
650 	if (irq_status & (R592_REG_MSC_IRQ_INSERT | R592_REG_MSC_IRQ_REMOVE)) {
651 
652 		bool card_was_added = irq_status & R592_REG_MSC_IRQ_INSERT;
653 		ret = IRQ_HANDLED;
654 
655 		message("IRQ: card %s", card_was_added ? "added" : "removed");
656 
657 		mod_timer(&dev->detect_timer,
658 			jiffies + msecs_to_jiffies(card_was_added ? 500 : 50));
659 	}
660 
661 	if (irq_status &
662 		(R592_REG_MSC_FIFO_DMA_DONE | R592_REG_MSC_FIFO_DMA_ERR)) {
663 		ret = IRQ_HANDLED;
664 
665 		if (irq_status & R592_REG_MSC_FIFO_DMA_ERR) {
666 			message("IRQ: DMA error");
667 			error = -EIO;
668 		} else {
669 			dbg_verbose("IRQ: dma done");
670 			error = 0;
671 		}
672 
673 		r592_stop_dma(dev, error);
674 		complete(&dev->dma_done);
675 	}
676 
677 	spin_unlock_irqrestore(&dev->irq_lock, flags);
678 	return ret;
679 }
680 
681 /* External inteface: set settings */
682 static int r592_set_param(struct memstick_host *host,
683 			enum memstick_param param, int value)
684 {
685 	struct r592_device *dev = memstick_priv(host);
686 
687 	switch (param) {
688 	case MEMSTICK_POWER:
689 		switch (value) {
690 		case MEMSTICK_POWER_ON:
691 			return r592_enable_device(dev, true);
692 		case MEMSTICK_POWER_OFF:
693 			return r592_enable_device(dev, false);
694 		default:
695 			return -EINVAL;
696 		}
697 	case MEMSTICK_INTERFACE:
698 		switch (value) {
699 		case MEMSTICK_SERIAL:
700 			return r592_set_mode(dev, 0);
701 		case MEMSTICK_PAR4:
702 			return r592_set_mode(dev, 1);
703 		default:
704 			return -EINVAL;
705 		}
706 	default:
707 		return -EINVAL;
708 	}
709 }
710 
711 /* External interface: submit requests */
712 static void r592_submit_req(struct memstick_host *host)
713 {
714 	struct r592_device *dev = memstick_priv(host);
715 	unsigned long flags;
716 
717 	if (dev->req)
718 		return;
719 
720 	spin_lock_irqsave(&dev->io_thread_lock, flags);
721 	if (wake_up_process(dev->io_thread))
722 		dbg_verbose("IO thread woken to process requests");
723 	spin_unlock_irqrestore(&dev->io_thread_lock, flags);
724 }
725 
726 static const struct pci_device_id r592_pci_id_tbl[] = {
727 
728 	{ PCI_VDEVICE(RICOH, 0x0592), },
729 	{ },
730 };
731 
732 /* Main entry */
733 static int r592_probe(struct pci_dev *pdev, const struct pci_device_id *id)
734 {
735 	int error = -ENOMEM;
736 	struct memstick_host *host;
737 	struct r592_device *dev;
738 
739 	/* Allocate memory */
740 	host = memstick_alloc_host(sizeof(struct r592_device), &pdev->dev);
741 	if (!host)
742 		goto error1;
743 
744 	dev = memstick_priv(host);
745 	dev->host = host;
746 	dev->pci_dev = pdev;
747 	pci_set_drvdata(pdev, dev);
748 
749 	/* pci initialization */
750 	error = pci_enable_device(pdev);
751 	if (error)
752 		goto error2;
753 
754 	pci_set_master(pdev);
755 	error = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
756 	if (error)
757 		goto error3;
758 
759 	error = pci_request_regions(pdev, DRV_NAME);
760 	if (error)
761 		goto error3;
762 
763 	dev->mmio = pci_ioremap_bar(pdev, 0);
764 	if (!dev->mmio)
765 		goto error4;
766 
767 	dev->irq = pdev->irq;
768 	spin_lock_init(&dev->irq_lock);
769 	spin_lock_init(&dev->io_thread_lock);
770 	init_completion(&dev->dma_done);
771 	INIT_KFIFO(dev->pio_fifo);
772 	setup_timer(&dev->detect_timer,
773 		r592_detect_timer, (long unsigned int)dev);
774 
775 	/* Host initialization */
776 	host->caps = MEMSTICK_CAP_PAR4;
777 	host->request = r592_submit_req;
778 	host->set_param = r592_set_param;
779 	r592_check_dma(dev);
780 
781 	dev->io_thread = kthread_run(r592_process_thread, dev, "r592_io");
782 	if (IS_ERR(dev->io_thread)) {
783 		error = PTR_ERR(dev->io_thread);
784 		goto error5;
785 	}
786 
787 	/* This is just a precation, so don't fail */
788 	dev->dummy_dma_page = pci_alloc_consistent(pdev, PAGE_SIZE,
789 		&dev->dummy_dma_page_physical_address);
790 	r592_stop_dma(dev , 0);
791 
792 	if (request_irq(dev->irq, &r592_irq, IRQF_SHARED,
793 			  DRV_NAME, dev))
794 		goto error6;
795 
796 	r592_update_card_detect(dev);
797 	if (memstick_add_host(host))
798 		goto error7;
799 
800 	message("driver successfully loaded");
801 	return 0;
802 error7:
803 	free_irq(dev->irq, dev);
804 error6:
805 	if (dev->dummy_dma_page)
806 		pci_free_consistent(pdev, PAGE_SIZE, dev->dummy_dma_page,
807 			dev->dummy_dma_page_physical_address);
808 
809 	kthread_stop(dev->io_thread);
810 error5:
811 	iounmap(dev->mmio);
812 error4:
813 	pci_release_regions(pdev);
814 error3:
815 	pci_disable_device(pdev);
816 error2:
817 	memstick_free_host(host);
818 error1:
819 	return error;
820 }
821 
822 static void r592_remove(struct pci_dev *pdev)
823 {
824 	int error = 0;
825 	struct r592_device *dev = pci_get_drvdata(pdev);
826 
827 	/* Stop the processing thread.
828 	That ensures that we won't take any more requests */
829 	kthread_stop(dev->io_thread);
830 
831 	r592_enable_device(dev, false);
832 
833 	while (!error && dev->req) {
834 		dev->req->error = -ETIME;
835 		error = memstick_next_req(dev->host, &dev->req);
836 	}
837 	memstick_remove_host(dev->host);
838 
839 	free_irq(dev->irq, dev);
840 	iounmap(dev->mmio);
841 	pci_release_regions(pdev);
842 	pci_disable_device(pdev);
843 	memstick_free_host(dev->host);
844 
845 	if (dev->dummy_dma_page)
846 		pci_free_consistent(pdev, PAGE_SIZE, dev->dummy_dma_page,
847 			dev->dummy_dma_page_physical_address);
848 }
849 
850 #ifdef CONFIG_PM_SLEEP
851 static int r592_suspend(struct device *core_dev)
852 {
853 	struct pci_dev *pdev = to_pci_dev(core_dev);
854 	struct r592_device *dev = pci_get_drvdata(pdev);
855 
856 	r592_clear_interrupts(dev);
857 	memstick_suspend_host(dev->host);
858 	del_timer_sync(&dev->detect_timer);
859 	return 0;
860 }
861 
862 static int r592_resume(struct device *core_dev)
863 {
864 	struct pci_dev *pdev = to_pci_dev(core_dev);
865 	struct r592_device *dev = pci_get_drvdata(pdev);
866 
867 	r592_clear_interrupts(dev);
868 	r592_enable_device(dev, false);
869 	memstick_resume_host(dev->host);
870 	r592_update_card_detect(dev);
871 	return 0;
872 }
873 #endif
874 
875 static SIMPLE_DEV_PM_OPS(r592_pm_ops, r592_suspend, r592_resume);
876 
877 MODULE_DEVICE_TABLE(pci, r592_pci_id_tbl);
878 
879 static struct pci_driver r852_pci_driver = {
880 	.name		= DRV_NAME,
881 	.id_table	= r592_pci_id_tbl,
882 	.probe		= r592_probe,
883 	.remove		= r592_remove,
884 	.driver.pm	= &r592_pm_ops,
885 };
886 
887 module_pci_driver(r852_pci_driver);
888 
889 module_param_named(enable_dma, r592_enable_dma, bool, S_IRUGO);
890 MODULE_PARM_DESC(enable_dma, "Enable usage of the DMA (default)");
891 module_param(debug, int, S_IRUGO | S_IWUSR);
892 MODULE_PARM_DESC(debug, "Debug level (0-3)");
893 
894 MODULE_LICENSE("GPL");
895 MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
896 MODULE_DESCRIPTION("Ricoh R5C592 Memstick/Memstick PRO card reader driver");
897