xref: /openbmc/linux/drivers/memstick/host/r592.c (revision aac28965)
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 			      DMA_TO_DEVICE : DMA_FROM_DEVICE);
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 		     DMA_TO_DEVICE : DMA_FROM_DEVICE);
314 
315 	return dev->dma_error;
316 }
317 
318 /*
319  * Writes the FIFO in 4 byte chunks.
320  * If length isn't 4 byte aligned, rest of the data if put to a fifo
321  * to be written later
322  * Use r592_flush_fifo_write to flush that fifo when writing for the
323  * last time
324  */
325 static void r592_write_fifo_pio(struct r592_device *dev,
326 					unsigned char *buffer, int len)
327 {
328 	/* flush spill from former write */
329 	if (!kfifo_is_empty(&dev->pio_fifo)) {
330 
331 		u8 tmp[4] = {0};
332 		int copy_len = kfifo_in(&dev->pio_fifo, buffer, len);
333 
334 		if (!kfifo_is_full(&dev->pio_fifo))
335 			return;
336 		len -= copy_len;
337 		buffer += copy_len;
338 
339 		copy_len = kfifo_out(&dev->pio_fifo, tmp, 4);
340 		WARN_ON(copy_len != 4);
341 		r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)tmp);
342 	}
343 
344 	WARN_ON(!kfifo_is_empty(&dev->pio_fifo));
345 
346 	/* write full dwords */
347 	while (len >= 4) {
348 		r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)buffer);
349 		buffer += 4;
350 		len -= 4;
351 	}
352 
353 	/* put remaining bytes to the spill */
354 	if (len)
355 		kfifo_in(&dev->pio_fifo, buffer, len);
356 }
357 
358 /* Flushes the temporary FIFO used to make aligned DWORD writes */
359 static void r592_flush_fifo_write(struct r592_device *dev)
360 {
361 	int ret;
362 	u8 buffer[4] = { 0 };
363 
364 	if (kfifo_is_empty(&dev->pio_fifo))
365 		return;
366 
367 	ret = kfifo_out(&dev->pio_fifo, buffer, 4);
368 	/* intentionally ignore __must_check return code */
369 	(void)ret;
370 	r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)buffer);
371 }
372 
373 /*
374  * Read a fifo in 4 bytes chunks.
375  * If input doesn't fit the buffer, it places bytes of last dword in spill
376  * buffer, so that they don't get lost on last read, just throw these away.
377  */
378 static void r592_read_fifo_pio(struct r592_device *dev,
379 						unsigned char *buffer, int len)
380 {
381 	u8 tmp[4];
382 
383 	/* Read from last spill */
384 	if (!kfifo_is_empty(&dev->pio_fifo)) {
385 		int bytes_copied =
386 			kfifo_out(&dev->pio_fifo, buffer, min(4, len));
387 		buffer += bytes_copied;
388 		len -= bytes_copied;
389 
390 		if (!kfifo_is_empty(&dev->pio_fifo))
391 			return;
392 	}
393 
394 	/* Reads dwords from FIFO */
395 	while (len >= 4) {
396 		*(u32 *)buffer = r592_read_reg_raw_be(dev, R592_FIFO_PIO);
397 		buffer += 4;
398 		len -= 4;
399 	}
400 
401 	if (len) {
402 		*(u32 *)tmp = r592_read_reg_raw_be(dev, R592_FIFO_PIO);
403 		kfifo_in(&dev->pio_fifo, tmp, 4);
404 		len -= kfifo_out(&dev->pio_fifo, buffer, len);
405 	}
406 
407 	WARN_ON(len);
408 	return;
409 }
410 
411 /* Transfers actual data using PIO. */
412 static int r592_transfer_fifo_pio(struct r592_device *dev)
413 {
414 	unsigned long flags;
415 
416 	bool is_write = dev->req->tpc >= MS_TPC_SET_RW_REG_ADRS;
417 	struct sg_mapping_iter miter;
418 
419 	kfifo_reset(&dev->pio_fifo);
420 
421 	if (!dev->req->long_data) {
422 		if (is_write) {
423 			r592_write_fifo_pio(dev, dev->req->data,
424 							dev->req->data_len);
425 			r592_flush_fifo_write(dev);
426 		} else
427 			r592_read_fifo_pio(dev, dev->req->data,
428 							dev->req->data_len);
429 		return 0;
430 	}
431 
432 	local_irq_save(flags);
433 	sg_miter_start(&miter, &dev->req->sg, 1, SG_MITER_ATOMIC |
434 		(is_write ? SG_MITER_FROM_SG : SG_MITER_TO_SG));
435 
436 	/* Do the transfer fifo<->memory*/
437 	while (sg_miter_next(&miter))
438 		if (is_write)
439 			r592_write_fifo_pio(dev, miter.addr, miter.length);
440 		else
441 			r592_read_fifo_pio(dev, miter.addr, miter.length);
442 
443 
444 	/* Write last few non aligned bytes*/
445 	if (is_write)
446 		r592_flush_fifo_write(dev);
447 
448 	sg_miter_stop(&miter);
449 	local_irq_restore(flags);
450 	return 0;
451 }
452 
453 /* Executes one TPC (data is read/written from small or large fifo) */
454 static void r592_execute_tpc(struct r592_device *dev)
455 {
456 	bool is_write;
457 	int len, error;
458 	u32 status, reg;
459 
460 	if (!dev->req) {
461 		message("BUG: tpc execution without request!");
462 		return;
463 	}
464 
465 	is_write = dev->req->tpc >= MS_TPC_SET_RW_REG_ADRS;
466 	len = dev->req->long_data ?
467 		dev->req->sg.length : dev->req->data_len;
468 
469 	/* Ensure that FIFO can hold the input data */
470 	if (len > R592_LFIFO_SIZE) {
471 		message("IO: hardware doesn't support TPCs longer that 512");
472 		error = -ENOSYS;
473 		goto out;
474 	}
475 
476 	if (!(r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_PRSNT)) {
477 		dbg("IO: refusing to send TPC because card is absent");
478 		error = -ENODEV;
479 		goto out;
480 	}
481 
482 	dbg("IO: executing %s LEN=%d",
483 			memstick_debug_get_tpc_name(dev->req->tpc), len);
484 
485 	/* Set IO direction */
486 	if (is_write)
487 		r592_set_reg_mask(dev, R592_IO, R592_IO_DIRECTION);
488 	else
489 		r592_clear_reg_mask(dev, R592_IO, R592_IO_DIRECTION);
490 
491 
492 	error = r592_test_fifo_empty(dev);
493 	if (error)
494 		goto out;
495 
496 	/* Transfer write data */
497 	if (is_write) {
498 		error = r592_transfer_fifo_dma(dev);
499 		if (error == -EINVAL)
500 			error = r592_transfer_fifo_pio(dev);
501 	}
502 
503 	if (error)
504 		goto out;
505 
506 	/* Trigger the TPC */
507 	reg = (len << R592_TPC_EXEC_LEN_SHIFT) |
508 		(dev->req->tpc << R592_TPC_EXEC_TPC_SHIFT) |
509 			R592_TPC_EXEC_BIG_FIFO;
510 
511 	r592_write_reg(dev, R592_TPC_EXEC, reg);
512 
513 	/* Wait for TPC completion */
514 	status = R592_STATUS_RDY;
515 	if (dev->req->need_card_int)
516 		status |= R592_STATUS_CED;
517 
518 	error = r592_wait_status(dev, status, status);
519 	if (error) {
520 		message("card didn't respond");
521 		goto out;
522 	}
523 
524 	/* Test IO errors */
525 	error = r592_test_io_error(dev);
526 	if (error) {
527 		dbg("IO error");
528 		goto out;
529 	}
530 
531 	/* Read data from FIFO */
532 	if (!is_write) {
533 		error = r592_transfer_fifo_dma(dev);
534 		if (error == -EINVAL)
535 			error = r592_transfer_fifo_pio(dev);
536 	}
537 
538 	/* read INT reg. This can be shortened with shifts, but that way
539 		its more readable */
540 	if (dev->parallel_mode && dev->req->need_card_int) {
541 
542 		dev->req->int_reg = 0;
543 		status = r592_read_reg(dev, R592_STATUS);
544 
545 		if (status & R592_STATUS_P_CMDNACK)
546 			dev->req->int_reg |= MEMSTICK_INT_CMDNAK;
547 		if (status & R592_STATUS_P_BREQ)
548 			dev->req->int_reg |= MEMSTICK_INT_BREQ;
549 		if (status & R592_STATUS_P_INTERR)
550 			dev->req->int_reg |= MEMSTICK_INT_ERR;
551 		if (status & R592_STATUS_P_CED)
552 			dev->req->int_reg |= MEMSTICK_INT_CED;
553 	}
554 
555 	if (error)
556 		dbg("FIFO read error");
557 out:
558 	dev->req->error = error;
559 	r592_clear_reg_mask(dev, R592_REG_MSC, R592_REG_MSC_LED);
560 	return;
561 }
562 
563 /* Main request processing thread */
564 static int r592_process_thread(void *data)
565 {
566 	int error;
567 	struct r592_device *dev = (struct r592_device *)data;
568 	unsigned long flags;
569 
570 	while (!kthread_should_stop()) {
571 		spin_lock_irqsave(&dev->io_thread_lock, flags);
572 		set_current_state(TASK_INTERRUPTIBLE);
573 		error = memstick_next_req(dev->host, &dev->req);
574 		spin_unlock_irqrestore(&dev->io_thread_lock, flags);
575 
576 		if (error) {
577 			if (error == -ENXIO || error == -EAGAIN) {
578 				dbg_verbose("IO: done IO, sleeping");
579 			} else {
580 				dbg("IO: unknown error from "
581 					"memstick_next_req %d", error);
582 			}
583 
584 			if (kthread_should_stop())
585 				set_current_state(TASK_RUNNING);
586 
587 			schedule();
588 		} else {
589 			set_current_state(TASK_RUNNING);
590 			r592_execute_tpc(dev);
591 		}
592 	}
593 	return 0;
594 }
595 
596 /* Reprogram chip to detect change in card state */
597 /* eg, if card is detected, arm it to detect removal, and vice versa */
598 static void r592_update_card_detect(struct r592_device *dev)
599 {
600 	u32 reg = r592_read_reg(dev, R592_REG_MSC);
601 	bool card_detected = reg & R592_REG_MSC_PRSNT;
602 
603 	dbg("update card detect. card state: %s", card_detected ?
604 		"present" : "absent");
605 
606 	reg &= ~((R592_REG_MSC_IRQ_REMOVE | R592_REG_MSC_IRQ_INSERT) << 16);
607 
608 	if (card_detected)
609 		reg |= (R592_REG_MSC_IRQ_REMOVE << 16);
610 	else
611 		reg |= (R592_REG_MSC_IRQ_INSERT << 16);
612 
613 	r592_write_reg(dev, R592_REG_MSC, reg);
614 }
615 
616 /* Timer routine that fires 1 second after last card detection event, */
617 static void r592_detect_timer(struct timer_list *t)
618 {
619 	struct r592_device *dev = from_timer(dev, t, detect_timer);
620 	r592_update_card_detect(dev);
621 	memstick_detect_change(dev->host);
622 }
623 
624 /* Interrupt handler */
625 static irqreturn_t r592_irq(int irq, void *data)
626 {
627 	struct r592_device *dev = (struct r592_device *)data;
628 	irqreturn_t ret = IRQ_NONE;
629 	u32 reg;
630 	u16 irq_enable, irq_status;
631 	unsigned long flags;
632 	int error;
633 
634 	spin_lock_irqsave(&dev->irq_lock, flags);
635 
636 	reg = r592_read_reg(dev, R592_REG_MSC);
637 	irq_enable = reg >> 16;
638 	irq_status = reg & 0xFFFF;
639 
640 	/* Ack the interrupts */
641 	reg &= ~irq_status;
642 	r592_write_reg(dev, R592_REG_MSC, reg);
643 
644 	/* Get the IRQ status minus bits that aren't enabled */
645 	irq_status &= (irq_enable);
646 
647 	/* Due to limitation of memstick core, we don't look at bits that
648 		indicate that card was removed/inserted and/or present */
649 	if (irq_status & (R592_REG_MSC_IRQ_INSERT | R592_REG_MSC_IRQ_REMOVE)) {
650 
651 		bool card_was_added = irq_status & R592_REG_MSC_IRQ_INSERT;
652 		ret = IRQ_HANDLED;
653 
654 		message("IRQ: card %s", card_was_added ? "added" : "removed");
655 
656 		mod_timer(&dev->detect_timer,
657 			jiffies + msecs_to_jiffies(card_was_added ? 500 : 50));
658 	}
659 
660 	if (irq_status &
661 		(R592_REG_MSC_FIFO_DMA_DONE | R592_REG_MSC_FIFO_DMA_ERR)) {
662 		ret = IRQ_HANDLED;
663 
664 		if (irq_status & R592_REG_MSC_FIFO_DMA_ERR) {
665 			message("IRQ: DMA error");
666 			error = -EIO;
667 		} else {
668 			dbg_verbose("IRQ: dma done");
669 			error = 0;
670 		}
671 
672 		r592_stop_dma(dev, error);
673 		complete(&dev->dma_done);
674 	}
675 
676 	spin_unlock_irqrestore(&dev->irq_lock, flags);
677 	return ret;
678 }
679 
680 /* External inteface: set settings */
681 static int r592_set_param(struct memstick_host *host,
682 			enum memstick_param param, int value)
683 {
684 	struct r592_device *dev = memstick_priv(host);
685 
686 	switch (param) {
687 	case MEMSTICK_POWER:
688 		switch (value) {
689 		case MEMSTICK_POWER_ON:
690 			return r592_enable_device(dev, true);
691 		case MEMSTICK_POWER_OFF:
692 			return r592_enable_device(dev, false);
693 		default:
694 			return -EINVAL;
695 		}
696 	case MEMSTICK_INTERFACE:
697 		switch (value) {
698 		case MEMSTICK_SERIAL:
699 			return r592_set_mode(dev, 0);
700 		case MEMSTICK_PAR4:
701 			return r592_set_mode(dev, 1);
702 		default:
703 			return -EINVAL;
704 		}
705 	default:
706 		return -EINVAL;
707 	}
708 }
709 
710 /* External interface: submit requests */
711 static void r592_submit_req(struct memstick_host *host)
712 {
713 	struct r592_device *dev = memstick_priv(host);
714 	unsigned long flags;
715 
716 	if (dev->req)
717 		return;
718 
719 	spin_lock_irqsave(&dev->io_thread_lock, flags);
720 	if (wake_up_process(dev->io_thread))
721 		dbg_verbose("IO thread woken to process requests");
722 	spin_unlock_irqrestore(&dev->io_thread_lock, flags);
723 }
724 
725 static const struct pci_device_id r592_pci_id_tbl[] = {
726 
727 	{ PCI_VDEVICE(RICOH, 0x0592), },
728 	{ },
729 };
730 
731 /* Main entry */
732 static int r592_probe(struct pci_dev *pdev, const struct pci_device_id *id)
733 {
734 	int error = -ENOMEM;
735 	struct memstick_host *host;
736 	struct r592_device *dev;
737 
738 	/* Allocate memory */
739 	host = memstick_alloc_host(sizeof(struct r592_device), &pdev->dev);
740 	if (!host)
741 		goto error1;
742 
743 	dev = memstick_priv(host);
744 	dev->host = host;
745 	dev->pci_dev = pdev;
746 	pci_set_drvdata(pdev, dev);
747 
748 	/* pci initialization */
749 	error = pci_enable_device(pdev);
750 	if (error)
751 		goto error2;
752 
753 	pci_set_master(pdev);
754 	error = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
755 	if (error)
756 		goto error3;
757 
758 	error = pci_request_regions(pdev, DRV_NAME);
759 	if (error)
760 		goto error3;
761 
762 	dev->mmio = pci_ioremap_bar(pdev, 0);
763 	if (!dev->mmio) {
764 		error = -ENOMEM;
765 		goto error4;
766 	}
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 	timer_setup(&dev->detect_timer, r592_detect_timer, 0);
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 = dma_alloc_coherent(&pdev->dev, PAGE_SIZE,
789 		&dev->dummy_dma_page_physical_address, GFP_KERNEL);
790 	r592_stop_dma(dev , 0);
791 
792 	error = request_irq(dev->irq, &r592_irq, IRQF_SHARED,
793 			  DRV_NAME, dev);
794 	if (error)
795 		goto error6;
796 
797 	r592_update_card_detect(dev);
798 	error = memstick_add_host(host);
799 	if (error)
800 		goto error7;
801 
802 	message("driver successfully loaded");
803 	return 0;
804 error7:
805 	free_irq(dev->irq, dev);
806 error6:
807 	if (dev->dummy_dma_page)
808 		dma_free_coherent(&pdev->dev, PAGE_SIZE, dev->dummy_dma_page,
809 			dev->dummy_dma_page_physical_address);
810 
811 	kthread_stop(dev->io_thread);
812 error5:
813 	iounmap(dev->mmio);
814 error4:
815 	pci_release_regions(pdev);
816 error3:
817 	pci_disable_device(pdev);
818 error2:
819 	memstick_free_host(host);
820 error1:
821 	return error;
822 }
823 
824 static void r592_remove(struct pci_dev *pdev)
825 {
826 	int error = 0;
827 	struct r592_device *dev = pci_get_drvdata(pdev);
828 
829 	/* Stop the processing thread.
830 	That ensures that we won't take any more requests */
831 	kthread_stop(dev->io_thread);
832 
833 	r592_enable_device(dev, false);
834 
835 	while (!error && dev->req) {
836 		dev->req->error = -ETIME;
837 		error = memstick_next_req(dev->host, &dev->req);
838 	}
839 	memstick_remove_host(dev->host);
840 
841 	if (dev->dummy_dma_page)
842 		dma_free_coherent(&pdev->dev, PAGE_SIZE, dev->dummy_dma_page,
843 			dev->dummy_dma_page_physical_address);
844 
845 	free_irq(dev->irq, dev);
846 	iounmap(dev->mmio);
847 	pci_release_regions(pdev);
848 	pci_disable_device(pdev);
849 	memstick_free_host(dev->host);
850 }
851 
852 #ifdef CONFIG_PM_SLEEP
853 static int r592_suspend(struct device *core_dev)
854 {
855 	struct r592_device *dev = dev_get_drvdata(core_dev);
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 r592_device *dev = dev_get_drvdata(core_dev);
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 r592_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(r592_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