xref: /openbmc/linux/drivers/memstick/host/r592.c (revision 3d37ef41)
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 	int ret;
363 	u8 buffer[4] = { 0 };
364 
365 	if (kfifo_is_empty(&dev->pio_fifo))
366 		return;
367 
368 	ret = kfifo_out(&dev->pio_fifo, buffer, 4);
369 	/* intentionally ignore __must_check return code */
370 	(void)ret;
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(struct timer_list *t)
619 {
620 	struct r592_device *dev = from_timer(dev, t, detect_timer);
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 = dma_set_mask(&pdev->dev, 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 		error = -ENOMEM;
766 		goto error4;
767 	}
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 	timer_setup(&dev->detect_timer, r592_detect_timer, 0);
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 	error = request_irq(dev->irq, &r592_irq, IRQF_SHARED,
794 			  DRV_NAME, dev);
795 	if (error)
796 		goto error6;
797 
798 	r592_update_card_detect(dev);
799 	error = memstick_add_host(host);
800 	if (error)
801 		goto error7;
802 
803 	message("driver successfully loaded");
804 	return 0;
805 error7:
806 	free_irq(dev->irq, dev);
807 error6:
808 	if (dev->dummy_dma_page)
809 		dma_free_coherent(&pdev->dev, PAGE_SIZE, dev->dummy_dma_page,
810 			dev->dummy_dma_page_physical_address);
811 
812 	kthread_stop(dev->io_thread);
813 error5:
814 	iounmap(dev->mmio);
815 error4:
816 	pci_release_regions(pdev);
817 error3:
818 	pci_disable_device(pdev);
819 error2:
820 	memstick_free_host(host);
821 error1:
822 	return error;
823 }
824 
825 static void r592_remove(struct pci_dev *pdev)
826 {
827 	int error = 0;
828 	struct r592_device *dev = pci_get_drvdata(pdev);
829 
830 	/* Stop the processing thread.
831 	That ensures that we won't take any more requests */
832 	kthread_stop(dev->io_thread);
833 
834 	r592_enable_device(dev, false);
835 
836 	while (!error && dev->req) {
837 		dev->req->error = -ETIME;
838 		error = memstick_next_req(dev->host, &dev->req);
839 	}
840 	memstick_remove_host(dev->host);
841 
842 	free_irq(dev->irq, dev);
843 	iounmap(dev->mmio);
844 	pci_release_regions(pdev);
845 	pci_disable_device(pdev);
846 	memstick_free_host(dev->host);
847 
848 	if (dev->dummy_dma_page)
849 		dma_free_coherent(&pdev->dev, PAGE_SIZE, dev->dummy_dma_page,
850 			dev->dummy_dma_page_physical_address);
851 }
852 
853 #ifdef CONFIG_PM_SLEEP
854 static int r592_suspend(struct device *core_dev)
855 {
856 	struct r592_device *dev = dev_get_drvdata(core_dev);
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 r592_device *dev = dev_get_drvdata(core_dev);
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