xref: /linux/drivers/memstick/host/r592.c (revision 37744feebc086908fd89760650f458ab19071750)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2010 - Maxim Levitsky
4  * driver for Ricoh memstick readers
5  */
6 
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/freezer.h>
10 #include <linux/jiffies.h>
11 #include <linux/interrupt.h>
12 #include <linux/pci.h>
13 #include <linux/pci_ids.h>
14 #include <linux/delay.h>
15 #include <linux/slab.h>
16 #include <linux/kthread.h>
17 #include <linux/sched.h>
18 #include <linux/highmem.h>
19 #include <asm/byteorder.h>
20 #include <linux/swab.h>
21 #include "r592.h"
22 
23 static bool r592_enable_dma = 1;
24 static int debug;
25 
26 static const char *tpc_names[] = {
27 	"MS_TPC_READ_MG_STATUS",
28 	"MS_TPC_READ_LONG_DATA",
29 	"MS_TPC_READ_SHORT_DATA",
30 	"MS_TPC_READ_REG",
31 	"MS_TPC_READ_QUAD_DATA",
32 	"INVALID",
33 	"MS_TPC_GET_INT",
34 	"MS_TPC_SET_RW_REG_ADRS",
35 	"MS_TPC_EX_SET_CMD",
36 	"MS_TPC_WRITE_QUAD_DATA",
37 	"MS_TPC_WRITE_REG",
38 	"MS_TPC_WRITE_SHORT_DATA",
39 	"MS_TPC_WRITE_LONG_DATA",
40 	"MS_TPC_SET_CMD",
41 };
42 
43 /**
44  * memstick_debug_get_tpc_name - debug helper that returns string for
45  * a TPC number
46  */
47 const char *memstick_debug_get_tpc_name(int tpc)
48 {
49 	return tpc_names[tpc-1];
50 }
51 EXPORT_SYMBOL(memstick_debug_get_tpc_name);
52 
53 
54 /* Read a register*/
55 static inline u32 r592_read_reg(struct r592_device *dev, int address)
56 {
57 	u32 value = readl(dev->mmio + address);
58 	dbg_reg("reg #%02d == 0x%08x", address, value);
59 	return value;
60 }
61 
62 /* Write a register */
63 static inline void r592_write_reg(struct r592_device *dev,
64 							int address, u32 value)
65 {
66 	dbg_reg("reg #%02d <- 0x%08x", address, value);
67 	writel(value, dev->mmio + address);
68 }
69 
70 /* Reads a big endian DWORD register */
71 static inline u32 r592_read_reg_raw_be(struct r592_device *dev, int address)
72 {
73 	u32 value = __raw_readl(dev->mmio + address);
74 	dbg_reg("reg #%02d == 0x%08x", address, value);
75 	return be32_to_cpu(value);
76 }
77 
78 /* Writes a big endian DWORD register */
79 static inline void r592_write_reg_raw_be(struct r592_device *dev,
80 							int address, u32 value)
81 {
82 	dbg_reg("reg #%02d <- 0x%08x", address, value);
83 	__raw_writel(cpu_to_be32(value), dev->mmio + address);
84 }
85 
86 /* Set specific bits in a register (little endian) */
87 static inline void r592_set_reg_mask(struct r592_device *dev,
88 							int address, u32 mask)
89 {
90 	u32 reg = readl(dev->mmio + address);
91 	dbg_reg("reg #%02d |= 0x%08x (old =0x%08x)", address, mask, reg);
92 	writel(reg | mask , dev->mmio + address);
93 }
94 
95 /* Clear specific bits in a register (little endian) */
96 static inline void r592_clear_reg_mask(struct r592_device *dev,
97 						int address, u32 mask)
98 {
99 	u32 reg = readl(dev->mmio + address);
100 	dbg_reg("reg #%02d &= 0x%08x (old = 0x%08x, mask = 0x%08x)",
101 						address, ~mask, reg, mask);
102 	writel(reg & ~mask, dev->mmio + address);
103 }
104 
105 
106 /* Wait for status bits while checking for errors */
107 static int r592_wait_status(struct r592_device *dev, u32 mask, u32 wanted_mask)
108 {
109 	unsigned long timeout = jiffies + msecs_to_jiffies(1000);
110 	u32 reg = r592_read_reg(dev, R592_STATUS);
111 
112 	if ((reg & mask) == wanted_mask)
113 		return 0;
114 
115 	while (time_before(jiffies, timeout)) {
116 
117 		reg = r592_read_reg(dev, R592_STATUS);
118 
119 		if ((reg & mask) == wanted_mask)
120 			return 0;
121 
122 		if (reg & (R592_STATUS_SEND_ERR | R592_STATUS_RECV_ERR))
123 			return -EIO;
124 
125 		cpu_relax();
126 	}
127 	return -ETIME;
128 }
129 
130 
131 /* Enable/disable device */
132 static int r592_enable_device(struct r592_device *dev, bool enable)
133 {
134 	dbg("%sabling the device", enable ? "en" : "dis");
135 
136 	if (enable) {
137 
138 		/* Power up the card */
139 		r592_write_reg(dev, R592_POWER, R592_POWER_0 | R592_POWER_1);
140 
141 		/* Perform a reset */
142 		r592_set_reg_mask(dev, R592_IO, R592_IO_RESET);
143 
144 		msleep(100);
145 	} else
146 		/* Power down the card */
147 		r592_write_reg(dev, R592_POWER, 0);
148 
149 	return 0;
150 }
151 
152 /* Set serial/parallel mode */
153 static int r592_set_mode(struct r592_device *dev, bool parallel_mode)
154 {
155 	if (!parallel_mode) {
156 		dbg("switching to serial mode");
157 
158 		/* Set serial mode */
159 		r592_write_reg(dev, R592_IO_MODE, R592_IO_MODE_SERIAL);
160 
161 		r592_clear_reg_mask(dev, R592_POWER, R592_POWER_20);
162 
163 	} else {
164 		dbg("switching to parallel mode");
165 
166 		/* This setting should be set _before_ switch TPC */
167 		r592_set_reg_mask(dev, R592_POWER, R592_POWER_20);
168 
169 		r592_clear_reg_mask(dev, R592_IO,
170 			R592_IO_SERIAL1 | R592_IO_SERIAL2);
171 
172 		/* Set the parallel mode now */
173 		r592_write_reg(dev, R592_IO_MODE, R592_IO_MODE_PARALLEL);
174 	}
175 
176 	dev->parallel_mode = parallel_mode;
177 	return 0;
178 }
179 
180 /* Perform a controller reset without powering down the card */
181 static void r592_host_reset(struct r592_device *dev)
182 {
183 	r592_set_reg_mask(dev, R592_IO, R592_IO_RESET);
184 	msleep(100);
185 	r592_set_mode(dev, dev->parallel_mode);
186 }
187 
188 #ifdef CONFIG_PM_SLEEP
189 /* Disable all hardware interrupts */
190 static void r592_clear_interrupts(struct r592_device *dev)
191 {
192 	/* Disable & ACK all interrupts */
193 	r592_clear_reg_mask(dev, R592_REG_MSC, IRQ_ALL_ACK_MASK);
194 	r592_clear_reg_mask(dev, R592_REG_MSC, IRQ_ALL_EN_MASK);
195 }
196 #endif
197 
198 /* Tests if there is an CRC error */
199 static int r592_test_io_error(struct r592_device *dev)
200 {
201 	if (!(r592_read_reg(dev, R592_STATUS) &
202 		(R592_STATUS_SEND_ERR | R592_STATUS_RECV_ERR)))
203 		return 0;
204 
205 	return -EIO;
206 }
207 
208 /* Ensure that FIFO is ready for use */
209 static int r592_test_fifo_empty(struct r592_device *dev)
210 {
211 	if (r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_FIFO_EMPTY)
212 		return 0;
213 
214 	dbg("FIFO not ready, trying to reset the device");
215 	r592_host_reset(dev);
216 
217 	if (r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_FIFO_EMPTY)
218 		return 0;
219 
220 	message("FIFO still not ready, giving up");
221 	return -EIO;
222 }
223 
224 /* Activates the DMA transfer from to FIFO */
225 static void r592_start_dma(struct r592_device *dev, bool is_write)
226 {
227 	unsigned long flags;
228 	u32 reg;
229 	spin_lock_irqsave(&dev->irq_lock, flags);
230 
231 	/* Ack interrupts (just in case) + enable them */
232 	r592_clear_reg_mask(dev, R592_REG_MSC, DMA_IRQ_ACK_MASK);
233 	r592_set_reg_mask(dev, R592_REG_MSC, DMA_IRQ_EN_MASK);
234 
235 	/* Set DMA address */
236 	r592_write_reg(dev, R592_FIFO_DMA, sg_dma_address(&dev->req->sg));
237 
238 	/* Enable the DMA */
239 	reg = r592_read_reg(dev, R592_FIFO_DMA_SETTINGS);
240 	reg |= R592_FIFO_DMA_SETTINGS_EN;
241 
242 	if (!is_write)
243 		reg |= R592_FIFO_DMA_SETTINGS_DIR;
244 	else
245 		reg &= ~R592_FIFO_DMA_SETTINGS_DIR;
246 	r592_write_reg(dev, R592_FIFO_DMA_SETTINGS, reg);
247 
248 	spin_unlock_irqrestore(&dev->irq_lock, flags);
249 }
250 
251 /* Cleanups DMA related settings */
252 static void r592_stop_dma(struct r592_device *dev, int error)
253 {
254 	r592_clear_reg_mask(dev, R592_FIFO_DMA_SETTINGS,
255 		R592_FIFO_DMA_SETTINGS_EN);
256 
257 	/* This is only a precation */
258 	r592_write_reg(dev, R592_FIFO_DMA,
259 			dev->dummy_dma_page_physical_address);
260 
261 	r592_clear_reg_mask(dev, R592_REG_MSC, DMA_IRQ_EN_MASK);
262 	r592_clear_reg_mask(dev, R592_REG_MSC, DMA_IRQ_ACK_MASK);
263 	dev->dma_error = error;
264 }
265 
266 /* Test if hardware supports DMA */
267 static void r592_check_dma(struct r592_device *dev)
268 {
269 	dev->dma_capable = r592_enable_dma &&
270 		(r592_read_reg(dev, R592_FIFO_DMA_SETTINGS) &
271 			R592_FIFO_DMA_SETTINGS_CAP);
272 }
273 
274 /* Transfers fifo contents in/out using DMA */
275 static int r592_transfer_fifo_dma(struct r592_device *dev)
276 {
277 	int len, sg_count;
278 	bool is_write;
279 
280 	if (!dev->dma_capable || !dev->req->long_data)
281 		return -EINVAL;
282 
283 	len = dev->req->sg.length;
284 	is_write = dev->req->data_dir == WRITE;
285 
286 	if (len != R592_LFIFO_SIZE)
287 		return -EINVAL;
288 
289 	dbg_verbose("doing dma transfer");
290 
291 	dev->dma_error = 0;
292 	reinit_completion(&dev->dma_done);
293 
294 	/* TODO: hidden assumption about nenth beeing always 1 */
295 	sg_count = dma_map_sg(&dev->pci_dev->dev, &dev->req->sg, 1, is_write ?
296 		PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
297 
298 	if (sg_count != 1 || sg_dma_len(&dev->req->sg) < R592_LFIFO_SIZE) {
299 		message("problem in dma_map_sg");
300 		return -EIO;
301 	}
302 
303 	r592_start_dma(dev, is_write);
304 
305 	/* Wait for DMA completion */
306 	if (!wait_for_completion_timeout(
307 			&dev->dma_done, msecs_to_jiffies(1000))) {
308 		message("DMA timeout");
309 		r592_stop_dma(dev, -ETIMEDOUT);
310 	}
311 
312 	dma_unmap_sg(&dev->pci_dev->dev, &dev->req->sg, 1, is_write ?
313 		PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
314 
315 
316 	return dev->dma_error;
317 }
318 
319 /*
320  * Writes the FIFO in 4 byte chunks.
321  * If length isn't 4 byte aligned, rest of the data if put to a fifo
322  * to be written later
323  * Use r592_flush_fifo_write to flush that fifo when writing for the
324  * last time
325  */
326 static void r592_write_fifo_pio(struct r592_device *dev,
327 					unsigned char *buffer, int len)
328 {
329 	/* flush spill from former write */
330 	if (!kfifo_is_empty(&dev->pio_fifo)) {
331 
332 		u8 tmp[4] = {0};
333 		int copy_len = kfifo_in(&dev->pio_fifo, buffer, len);
334 
335 		if (!kfifo_is_full(&dev->pio_fifo))
336 			return;
337 		len -= copy_len;
338 		buffer += copy_len;
339 
340 		copy_len = kfifo_out(&dev->pio_fifo, tmp, 4);
341 		WARN_ON(copy_len != 4);
342 		r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)tmp);
343 	}
344 
345 	WARN_ON(!kfifo_is_empty(&dev->pio_fifo));
346 
347 	/* write full dwords */
348 	while (len >= 4) {
349 		r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)buffer);
350 		buffer += 4;
351 		len -= 4;
352 	}
353 
354 	/* put remaining bytes to the spill */
355 	if (len)
356 		kfifo_in(&dev->pio_fifo, buffer, len);
357 }
358 
359 /* Flushes the temporary FIFO used to make aligned DWORD writes */
360 static void r592_flush_fifo_write(struct r592_device *dev)
361 {
362 	u8 buffer[4] = { 0 };
363 	int len;
364 
365 	if (kfifo_is_empty(&dev->pio_fifo))
366 		return;
367 
368 	len = kfifo_out(&dev->pio_fifo, buffer, 4);
369 	r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)buffer);
370 }
371 
372 /*
373  * Read a fifo in 4 bytes chunks.
374  * If input doesn't fit the buffer, it places bytes of last dword in spill
375  * buffer, so that they don't get lost on last read, just throw these away.
376  */
377 static void r592_read_fifo_pio(struct r592_device *dev,
378 						unsigned char *buffer, int len)
379 {
380 	u8 tmp[4];
381 
382 	/* Read from last spill */
383 	if (!kfifo_is_empty(&dev->pio_fifo)) {
384 		int bytes_copied =
385 			kfifo_out(&dev->pio_fifo, buffer, min(4, len));
386 		buffer += bytes_copied;
387 		len -= bytes_copied;
388 
389 		if (!kfifo_is_empty(&dev->pio_fifo))
390 			return;
391 	}
392 
393 	/* Reads dwords from FIFO */
394 	while (len >= 4) {
395 		*(u32 *)buffer = r592_read_reg_raw_be(dev, R592_FIFO_PIO);
396 		buffer += 4;
397 		len -= 4;
398 	}
399 
400 	if (len) {
401 		*(u32 *)tmp = r592_read_reg_raw_be(dev, R592_FIFO_PIO);
402 		kfifo_in(&dev->pio_fifo, tmp, 4);
403 		len -= kfifo_out(&dev->pio_fifo, buffer, len);
404 	}
405 
406 	WARN_ON(len);
407 	return;
408 }
409 
410 /* Transfers actual data using PIO. */
411 static int r592_transfer_fifo_pio(struct r592_device *dev)
412 {
413 	unsigned long flags;
414 
415 	bool is_write = dev->req->tpc >= MS_TPC_SET_RW_REG_ADRS;
416 	struct sg_mapping_iter miter;
417 
418 	kfifo_reset(&dev->pio_fifo);
419 
420 	if (!dev->req->long_data) {
421 		if (is_write) {
422 			r592_write_fifo_pio(dev, dev->req->data,
423 							dev->req->data_len);
424 			r592_flush_fifo_write(dev);
425 		} else
426 			r592_read_fifo_pio(dev, dev->req->data,
427 							dev->req->data_len);
428 		return 0;
429 	}
430 
431 	local_irq_save(flags);
432 	sg_miter_start(&miter, &dev->req->sg, 1, SG_MITER_ATOMIC |
433 		(is_write ? SG_MITER_FROM_SG : SG_MITER_TO_SG));
434 
435 	/* Do the transfer fifo<->memory*/
436 	while (sg_miter_next(&miter))
437 		if (is_write)
438 			r592_write_fifo_pio(dev, miter.addr, miter.length);
439 		else
440 			r592_read_fifo_pio(dev, miter.addr, miter.length);
441 
442 
443 	/* Write last few non aligned bytes*/
444 	if (is_write)
445 		r592_flush_fifo_write(dev);
446 
447 	sg_miter_stop(&miter);
448 	local_irq_restore(flags);
449 	return 0;
450 }
451 
452 /* Executes one TPC (data is read/written from small or large fifo) */
453 static void r592_execute_tpc(struct r592_device *dev)
454 {
455 	bool is_write;
456 	int len, error;
457 	u32 status, reg;
458 
459 	if (!dev->req) {
460 		message("BUG: tpc execution without request!");
461 		return;
462 	}
463 
464 	is_write = dev->req->tpc >= MS_TPC_SET_RW_REG_ADRS;
465 	len = dev->req->long_data ?
466 		dev->req->sg.length : dev->req->data_len;
467 
468 	/* Ensure that FIFO can hold the input data */
469 	if (len > R592_LFIFO_SIZE) {
470 		message("IO: hardware doesn't support TPCs longer that 512");
471 		error = -ENOSYS;
472 		goto out;
473 	}
474 
475 	if (!(r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_PRSNT)) {
476 		dbg("IO: refusing to send TPC because card is absent");
477 		error = -ENODEV;
478 		goto out;
479 	}
480 
481 	dbg("IO: executing %s LEN=%d",
482 			memstick_debug_get_tpc_name(dev->req->tpc), len);
483 
484 	/* Set IO direction */
485 	if (is_write)
486 		r592_set_reg_mask(dev, R592_IO, R592_IO_DIRECTION);
487 	else
488 		r592_clear_reg_mask(dev, R592_IO, R592_IO_DIRECTION);
489 
490 
491 	error = r592_test_fifo_empty(dev);
492 	if (error)
493 		goto out;
494 
495 	/* Transfer write data */
496 	if (is_write) {
497 		error = r592_transfer_fifo_dma(dev);
498 		if (error == -EINVAL)
499 			error = r592_transfer_fifo_pio(dev);
500 	}
501 
502 	if (error)
503 		goto out;
504 
505 	/* Trigger the TPC */
506 	reg = (len << R592_TPC_EXEC_LEN_SHIFT) |
507 		(dev->req->tpc << R592_TPC_EXEC_TPC_SHIFT) |
508 			R592_TPC_EXEC_BIG_FIFO;
509 
510 	r592_write_reg(dev, R592_TPC_EXEC, reg);
511 
512 	/* Wait for TPC completion */
513 	status = R592_STATUS_RDY;
514 	if (dev->req->need_card_int)
515 		status |= R592_STATUS_CED;
516 
517 	error = r592_wait_status(dev, status, status);
518 	if (error) {
519 		message("card didn't respond");
520 		goto out;
521 	}
522 
523 	/* Test IO errors */
524 	error = r592_test_io_error(dev);
525 	if (error) {
526 		dbg("IO error");
527 		goto out;
528 	}
529 
530 	/* Read data from FIFO */
531 	if (!is_write) {
532 		error = r592_transfer_fifo_dma(dev);
533 		if (error == -EINVAL)
534 			error = r592_transfer_fifo_pio(dev);
535 	}
536 
537 	/* read INT reg. This can be shortened with shifts, but that way
538 		its more readable */
539 	if (dev->parallel_mode && dev->req->need_card_int) {
540 
541 		dev->req->int_reg = 0;
542 		status = r592_read_reg(dev, R592_STATUS);
543 
544 		if (status & R592_STATUS_P_CMDNACK)
545 			dev->req->int_reg |= MEMSTICK_INT_CMDNAK;
546 		if (status & R592_STATUS_P_BREQ)
547 			dev->req->int_reg |= MEMSTICK_INT_BREQ;
548 		if (status & R592_STATUS_P_INTERR)
549 			dev->req->int_reg |= MEMSTICK_INT_ERR;
550 		if (status & R592_STATUS_P_CED)
551 			dev->req->int_reg |= MEMSTICK_INT_CED;
552 	}
553 
554 	if (error)
555 		dbg("FIFO read error");
556 out:
557 	dev->req->error = error;
558 	r592_clear_reg_mask(dev, R592_REG_MSC, R592_REG_MSC_LED);
559 	return;
560 }
561 
562 /* Main request processing thread */
563 static int r592_process_thread(void *data)
564 {
565 	int error;
566 	struct r592_device *dev = (struct r592_device *)data;
567 	unsigned long flags;
568 
569 	while (!kthread_should_stop()) {
570 		spin_lock_irqsave(&dev->io_thread_lock, flags);
571 		set_current_state(TASK_INTERRUPTIBLE);
572 		error = memstick_next_req(dev->host, &dev->req);
573 		spin_unlock_irqrestore(&dev->io_thread_lock, flags);
574 
575 		if (error) {
576 			if (error == -ENXIO || error == -EAGAIN) {
577 				dbg_verbose("IO: done IO, sleeping");
578 			} else {
579 				dbg("IO: unknown error from "
580 					"memstick_next_req %d", error);
581 			}
582 
583 			if (kthread_should_stop())
584 				set_current_state(TASK_RUNNING);
585 
586 			schedule();
587 		} else {
588 			set_current_state(TASK_RUNNING);
589 			r592_execute_tpc(dev);
590 		}
591 	}
592 	return 0;
593 }
594 
595 /* Reprogram chip to detect change in card state */
596 /* eg, if card is detected, arm it to detect removal, and vice versa */
597 static void r592_update_card_detect(struct r592_device *dev)
598 {
599 	u32 reg = r592_read_reg(dev, R592_REG_MSC);
600 	bool card_detected = reg & R592_REG_MSC_PRSNT;
601 
602 	dbg("update card detect. card state: %s", card_detected ?
603 		"present" : "absent");
604 
605 	reg &= ~((R592_REG_MSC_IRQ_REMOVE | R592_REG_MSC_IRQ_INSERT) << 16);
606 
607 	if (card_detected)
608 		reg |= (R592_REG_MSC_IRQ_REMOVE << 16);
609 	else
610 		reg |= (R592_REG_MSC_IRQ_INSERT << 16);
611 
612 	r592_write_reg(dev, R592_REG_MSC, reg);
613 }
614 
615 /* Timer routine that fires 1 second after last card detection event, */
616 static void r592_detect_timer(struct timer_list *t)
617 {
618 	struct r592_device *dev = from_timer(dev, t, detect_timer);
619 	r592_update_card_detect(dev);
620 	memstick_detect_change(dev->host);
621 }
622 
623 /* Interrupt handler */
624 static irqreturn_t r592_irq(int irq, void *data)
625 {
626 	struct r592_device *dev = (struct r592_device *)data;
627 	irqreturn_t ret = IRQ_NONE;
628 	u32 reg;
629 	u16 irq_enable, irq_status;
630 	unsigned long flags;
631 	int error;
632 
633 	spin_lock_irqsave(&dev->irq_lock, flags);
634 
635 	reg = r592_read_reg(dev, R592_REG_MSC);
636 	irq_enable = reg >> 16;
637 	irq_status = reg & 0xFFFF;
638 
639 	/* Ack the interrupts */
640 	reg &= ~irq_status;
641 	r592_write_reg(dev, R592_REG_MSC, reg);
642 
643 	/* Get the IRQ status minus bits that aren't enabled */
644 	irq_status &= (irq_enable);
645 
646 	/* Due to limitation of memstick core, we don't look at bits that
647 		indicate that card was removed/inserted and/or present */
648 	if (irq_status & (R592_REG_MSC_IRQ_INSERT | R592_REG_MSC_IRQ_REMOVE)) {
649 
650 		bool card_was_added = irq_status & R592_REG_MSC_IRQ_INSERT;
651 		ret = IRQ_HANDLED;
652 
653 		message("IRQ: card %s", card_was_added ? "added" : "removed");
654 
655 		mod_timer(&dev->detect_timer,
656 			jiffies + msecs_to_jiffies(card_was_added ? 500 : 50));
657 	}
658 
659 	if (irq_status &
660 		(R592_REG_MSC_FIFO_DMA_DONE | R592_REG_MSC_FIFO_DMA_ERR)) {
661 		ret = IRQ_HANDLED;
662 
663 		if (irq_status & R592_REG_MSC_FIFO_DMA_ERR) {
664 			message("IRQ: DMA error");
665 			error = -EIO;
666 		} else {
667 			dbg_verbose("IRQ: dma done");
668 			error = 0;
669 		}
670 
671 		r592_stop_dma(dev, error);
672 		complete(&dev->dma_done);
673 	}
674 
675 	spin_unlock_irqrestore(&dev->irq_lock, flags);
676 	return ret;
677 }
678 
679 /* External inteface: set settings */
680 static int r592_set_param(struct memstick_host *host,
681 			enum memstick_param param, int value)
682 {
683 	struct r592_device *dev = memstick_priv(host);
684 
685 	switch (param) {
686 	case MEMSTICK_POWER:
687 		switch (value) {
688 		case MEMSTICK_POWER_ON:
689 			return r592_enable_device(dev, true);
690 		case MEMSTICK_POWER_OFF:
691 			return r592_enable_device(dev, false);
692 		default:
693 			return -EINVAL;
694 		}
695 	case MEMSTICK_INTERFACE:
696 		switch (value) {
697 		case MEMSTICK_SERIAL:
698 			return r592_set_mode(dev, 0);
699 		case MEMSTICK_PAR4:
700 			return r592_set_mode(dev, 1);
701 		default:
702 			return -EINVAL;
703 		}
704 	default:
705 		return -EINVAL;
706 	}
707 }
708 
709 /* External interface: submit requests */
710 static void r592_submit_req(struct memstick_host *host)
711 {
712 	struct r592_device *dev = memstick_priv(host);
713 	unsigned long flags;
714 
715 	if (dev->req)
716 		return;
717 
718 	spin_lock_irqsave(&dev->io_thread_lock, flags);
719 	if (wake_up_process(dev->io_thread))
720 		dbg_verbose("IO thread woken to process requests");
721 	spin_unlock_irqrestore(&dev->io_thread_lock, flags);
722 }
723 
724 static const struct pci_device_id r592_pci_id_tbl[] = {
725 
726 	{ PCI_VDEVICE(RICOH, 0x0592), },
727 	{ },
728 };
729 
730 /* Main entry */
731 static int r592_probe(struct pci_dev *pdev, const struct pci_device_id *id)
732 {
733 	int error = -ENOMEM;
734 	struct memstick_host *host;
735 	struct r592_device *dev;
736 
737 	/* Allocate memory */
738 	host = memstick_alloc_host(sizeof(struct r592_device), &pdev->dev);
739 	if (!host)
740 		goto error1;
741 
742 	dev = memstick_priv(host);
743 	dev->host = host;
744 	dev->pci_dev = pdev;
745 	pci_set_drvdata(pdev, dev);
746 
747 	/* pci initialization */
748 	error = pci_enable_device(pdev);
749 	if (error)
750 		goto error2;
751 
752 	pci_set_master(pdev);
753 	error = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
754 	if (error)
755 		goto error3;
756 
757 	error = pci_request_regions(pdev, DRV_NAME);
758 	if (error)
759 		goto error3;
760 
761 	dev->mmio = pci_ioremap_bar(pdev, 0);
762 	if (!dev->mmio)
763 		goto error4;
764 
765 	dev->irq = pdev->irq;
766 	spin_lock_init(&dev->irq_lock);
767 	spin_lock_init(&dev->io_thread_lock);
768 	init_completion(&dev->dma_done);
769 	INIT_KFIFO(dev->pio_fifo);
770 	timer_setup(&dev->detect_timer, r592_detect_timer, 0);
771 
772 	/* Host initialization */
773 	host->caps = MEMSTICK_CAP_PAR4;
774 	host->request = r592_submit_req;
775 	host->set_param = r592_set_param;
776 	r592_check_dma(dev);
777 
778 	dev->io_thread = kthread_run(r592_process_thread, dev, "r592_io");
779 	if (IS_ERR(dev->io_thread)) {
780 		error = PTR_ERR(dev->io_thread);
781 		goto error5;
782 	}
783 
784 	/* This is just a precation, so don't fail */
785 	dev->dummy_dma_page = dma_alloc_coherent(&pdev->dev, PAGE_SIZE,
786 		&dev->dummy_dma_page_physical_address, GFP_KERNEL);
787 	r592_stop_dma(dev , 0);
788 
789 	if (request_irq(dev->irq, &r592_irq, IRQF_SHARED,
790 			  DRV_NAME, dev))
791 		goto error6;
792 
793 	r592_update_card_detect(dev);
794 	if (memstick_add_host(host))
795 		goto error7;
796 
797 	message("driver successfully loaded");
798 	return 0;
799 error7:
800 	free_irq(dev->irq, dev);
801 error6:
802 	if (dev->dummy_dma_page)
803 		dma_free_coherent(&pdev->dev, PAGE_SIZE, dev->dummy_dma_page,
804 			dev->dummy_dma_page_physical_address);
805 
806 	kthread_stop(dev->io_thread);
807 error5:
808 	iounmap(dev->mmio);
809 error4:
810 	pci_release_regions(pdev);
811 error3:
812 	pci_disable_device(pdev);
813 error2:
814 	memstick_free_host(host);
815 error1:
816 	return error;
817 }
818 
819 static void r592_remove(struct pci_dev *pdev)
820 {
821 	int error = 0;
822 	struct r592_device *dev = pci_get_drvdata(pdev);
823 
824 	/* Stop the processing thread.
825 	That ensures that we won't take any more requests */
826 	kthread_stop(dev->io_thread);
827 
828 	r592_enable_device(dev, false);
829 
830 	while (!error && dev->req) {
831 		dev->req->error = -ETIME;
832 		error = memstick_next_req(dev->host, &dev->req);
833 	}
834 	memstick_remove_host(dev->host);
835 
836 	free_irq(dev->irq, dev);
837 	iounmap(dev->mmio);
838 	pci_release_regions(pdev);
839 	pci_disable_device(pdev);
840 	memstick_free_host(dev->host);
841 
842 	if (dev->dummy_dma_page)
843 		dma_free_coherent(&pdev->dev, PAGE_SIZE, dev->dummy_dma_page,
844 			dev->dummy_dma_page_physical_address);
845 }
846 
847 #ifdef CONFIG_PM_SLEEP
848 static int r592_suspend(struct device *core_dev)
849 {
850 	struct r592_device *dev = dev_get_drvdata(core_dev);
851 
852 	r592_clear_interrupts(dev);
853 	memstick_suspend_host(dev->host);
854 	del_timer_sync(&dev->detect_timer);
855 	return 0;
856 }
857 
858 static int r592_resume(struct device *core_dev)
859 {
860 	struct r592_device *dev = dev_get_drvdata(core_dev);
861 
862 	r592_clear_interrupts(dev);
863 	r592_enable_device(dev, false);
864 	memstick_resume_host(dev->host);
865 	r592_update_card_detect(dev);
866 	return 0;
867 }
868 #endif
869 
870 static SIMPLE_DEV_PM_OPS(r592_pm_ops, r592_suspend, r592_resume);
871 
872 MODULE_DEVICE_TABLE(pci, r592_pci_id_tbl);
873 
874 static struct pci_driver r852_pci_driver = {
875 	.name		= DRV_NAME,
876 	.id_table	= r592_pci_id_tbl,
877 	.probe		= r592_probe,
878 	.remove		= r592_remove,
879 	.driver.pm	= &r592_pm_ops,
880 };
881 
882 module_pci_driver(r852_pci_driver);
883 
884 module_param_named(enable_dma, r592_enable_dma, bool, S_IRUGO);
885 MODULE_PARM_DESC(enable_dma, "Enable usage of the DMA (default)");
886 module_param(debug, int, S_IRUGO | S_IWUSR);
887 MODULE_PARM_DESC(debug, "Debug level (0-3)");
888 
889 MODULE_LICENSE("GPL");
890 MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
891 MODULE_DESCRIPTION("Ricoh R5C592 Memstick/Memstick PRO card reader driver");
892