xref: /linux/drivers/memstick/host/r592.c (revision 8e07e0e3964ca4e23ce7b68e2096fe660a888942)
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 static __maybe_unused const char *memstick_debug_get_tpc_name(int tpc)
48 {
49 	return tpc_names[tpc-1];
50 }
51 
52 /* Read a register*/
53 static inline u32 r592_read_reg(struct r592_device *dev, int address)
54 {
55 	u32 value = readl(dev->mmio + address);
56 	dbg_reg("reg #%02d == 0x%08x", address, value);
57 	return value;
58 }
59 
60 /* Write a register */
61 static inline void r592_write_reg(struct r592_device *dev,
62 							int address, u32 value)
63 {
64 	dbg_reg("reg #%02d <- 0x%08x", address, value);
65 	writel(value, dev->mmio + address);
66 }
67 
68 /* Reads a big endian DWORD register */
69 static inline u32 r592_read_reg_raw_be(struct r592_device *dev, int address)
70 {
71 	u32 value = __raw_readl(dev->mmio + address);
72 	dbg_reg("reg #%02d == 0x%08x", address, value);
73 	return be32_to_cpu(value);
74 }
75 
76 /* Writes a big endian DWORD register */
77 static inline void r592_write_reg_raw_be(struct r592_device *dev,
78 							int address, u32 value)
79 {
80 	dbg_reg("reg #%02d <- 0x%08x", address, value);
81 	__raw_writel(cpu_to_be32(value), dev->mmio + address);
82 }
83 
84 /* Set specific bits in a register (little endian) */
85 static inline void r592_set_reg_mask(struct r592_device *dev,
86 							int address, u32 mask)
87 {
88 	u32 reg = readl(dev->mmio + address);
89 	dbg_reg("reg #%02d |= 0x%08x (old =0x%08x)", address, mask, reg);
90 	writel(reg | mask , dev->mmio + address);
91 }
92 
93 /* Clear specific bits in a register (little endian) */
94 static inline void r592_clear_reg_mask(struct r592_device *dev,
95 						int address, u32 mask)
96 {
97 	u32 reg = readl(dev->mmio + address);
98 	dbg_reg("reg #%02d &= 0x%08x (old = 0x%08x, mask = 0x%08x)",
99 						address, ~mask, reg, mask);
100 	writel(reg & ~mask, dev->mmio + address);
101 }
102 
103 
104 /* Wait for status bits while checking for errors */
105 static int r592_wait_status(struct r592_device *dev, u32 mask, u32 wanted_mask)
106 {
107 	unsigned long timeout = jiffies + msecs_to_jiffies(1000);
108 	u32 reg = r592_read_reg(dev, R592_STATUS);
109 
110 	if ((reg & mask) == wanted_mask)
111 		return 0;
112 
113 	while (time_before(jiffies, timeout)) {
114 
115 		reg = r592_read_reg(dev, R592_STATUS);
116 
117 		if ((reg & mask) == wanted_mask)
118 			return 0;
119 
120 		if (reg & (R592_STATUS_SEND_ERR | R592_STATUS_RECV_ERR))
121 			return -EIO;
122 
123 		cpu_relax();
124 	}
125 	return -ETIME;
126 }
127 
128 
129 /* Enable/disable device */
130 static int r592_enable_device(struct r592_device *dev, bool enable)
131 {
132 	dbg("%sabling the device", enable ? "en" : "dis");
133 
134 	if (enable) {
135 
136 		/* Power up the card */
137 		r592_write_reg(dev, R592_POWER, R592_POWER_0 | R592_POWER_1);
138 
139 		/* Perform a reset */
140 		r592_set_reg_mask(dev, R592_IO, R592_IO_RESET);
141 
142 		msleep(100);
143 	} else
144 		/* Power down the card */
145 		r592_write_reg(dev, R592_POWER, 0);
146 
147 	return 0;
148 }
149 
150 /* Set serial/parallel mode */
151 static int r592_set_mode(struct r592_device *dev, bool parallel_mode)
152 {
153 	if (!parallel_mode) {
154 		dbg("switching to serial mode");
155 
156 		/* Set serial mode */
157 		r592_write_reg(dev, R592_IO_MODE, R592_IO_MODE_SERIAL);
158 
159 		r592_clear_reg_mask(dev, R592_POWER, R592_POWER_20);
160 
161 	} else {
162 		dbg("switching to parallel mode");
163 
164 		/* This setting should be set _before_ switch TPC */
165 		r592_set_reg_mask(dev, R592_POWER, R592_POWER_20);
166 
167 		r592_clear_reg_mask(dev, R592_IO,
168 			R592_IO_SERIAL1 | R592_IO_SERIAL2);
169 
170 		/* Set the parallel mode now */
171 		r592_write_reg(dev, R592_IO_MODE, R592_IO_MODE_PARALLEL);
172 	}
173 
174 	dev->parallel_mode = parallel_mode;
175 	return 0;
176 }
177 
178 /* Perform a controller reset without powering down the card */
179 static void r592_host_reset(struct r592_device *dev)
180 {
181 	r592_set_reg_mask(dev, R592_IO, R592_IO_RESET);
182 	msleep(100);
183 	r592_set_mode(dev, dev->parallel_mode);
184 }
185 
186 #ifdef CONFIG_PM_SLEEP
187 /* Disable all hardware interrupts */
188 static void r592_clear_interrupts(struct r592_device *dev)
189 {
190 	/* Disable & ACK all interrupts */
191 	r592_clear_reg_mask(dev, R592_REG_MSC, IRQ_ALL_ACK_MASK);
192 	r592_clear_reg_mask(dev, R592_REG_MSC, IRQ_ALL_EN_MASK);
193 }
194 #endif
195 
196 /* Tests if there is an CRC error */
197 static int r592_test_io_error(struct r592_device *dev)
198 {
199 	if (!(r592_read_reg(dev, R592_STATUS) &
200 		(R592_STATUS_SEND_ERR | R592_STATUS_RECV_ERR)))
201 		return 0;
202 
203 	return -EIO;
204 }
205 
206 /* Ensure that FIFO is ready for use */
207 static int r592_test_fifo_empty(struct r592_device *dev)
208 {
209 	if (r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_FIFO_EMPTY)
210 		return 0;
211 
212 	dbg("FIFO not ready, trying to reset the device");
213 	r592_host_reset(dev);
214 
215 	if (r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_FIFO_EMPTY)
216 		return 0;
217 
218 	message("FIFO still not ready, giving up");
219 	return -EIO;
220 }
221 
222 /* Activates the DMA transfer from to FIFO */
223 static void r592_start_dma(struct r592_device *dev, bool is_write)
224 {
225 	unsigned long flags;
226 	u32 reg;
227 	spin_lock_irqsave(&dev->irq_lock, flags);
228 
229 	/* Ack interrupts (just in case) + enable them */
230 	r592_clear_reg_mask(dev, R592_REG_MSC, DMA_IRQ_ACK_MASK);
231 	r592_set_reg_mask(dev, R592_REG_MSC, DMA_IRQ_EN_MASK);
232 
233 	/* Set DMA address */
234 	r592_write_reg(dev, R592_FIFO_DMA, sg_dma_address(&dev->req->sg));
235 
236 	/* Enable the DMA */
237 	reg = r592_read_reg(dev, R592_FIFO_DMA_SETTINGS);
238 	reg |= R592_FIFO_DMA_SETTINGS_EN;
239 
240 	if (!is_write)
241 		reg |= R592_FIFO_DMA_SETTINGS_DIR;
242 	else
243 		reg &= ~R592_FIFO_DMA_SETTINGS_DIR;
244 	r592_write_reg(dev, R592_FIFO_DMA_SETTINGS, reg);
245 
246 	spin_unlock_irqrestore(&dev->irq_lock, flags);
247 }
248 
249 /* Cleanups DMA related settings */
250 static void r592_stop_dma(struct r592_device *dev, int error)
251 {
252 	r592_clear_reg_mask(dev, R592_FIFO_DMA_SETTINGS,
253 		R592_FIFO_DMA_SETTINGS_EN);
254 
255 	/* This is only a precation */
256 	r592_write_reg(dev, R592_FIFO_DMA,
257 			dev->dummy_dma_page_physical_address);
258 
259 	r592_clear_reg_mask(dev, R592_REG_MSC, DMA_IRQ_EN_MASK);
260 	r592_clear_reg_mask(dev, R592_REG_MSC, DMA_IRQ_ACK_MASK);
261 	dev->dma_error = error;
262 }
263 
264 /* Test if hardware supports DMA */
265 static void r592_check_dma(struct r592_device *dev)
266 {
267 	dev->dma_capable = r592_enable_dma &&
268 		(r592_read_reg(dev, R592_FIFO_DMA_SETTINGS) &
269 			R592_FIFO_DMA_SETTINGS_CAP);
270 }
271 
272 /* Transfers fifo contents in/out using DMA */
273 static int r592_transfer_fifo_dma(struct r592_device *dev)
274 {
275 	int len, sg_count;
276 	bool is_write;
277 
278 	if (!dev->dma_capable || !dev->req->long_data)
279 		return -EINVAL;
280 
281 	len = dev->req->sg.length;
282 	is_write = dev->req->data_dir == WRITE;
283 
284 	if (len != R592_LFIFO_SIZE)
285 		return -EINVAL;
286 
287 	dbg_verbose("doing dma transfer");
288 
289 	dev->dma_error = 0;
290 	reinit_completion(&dev->dma_done);
291 
292 	/* TODO: hidden assumption about nenth beeing always 1 */
293 	sg_count = dma_map_sg(&dev->pci_dev->dev, &dev->req->sg, 1, is_write ?
294 			      DMA_TO_DEVICE : DMA_FROM_DEVICE);
295 
296 	if (sg_count != 1 || sg_dma_len(&dev->req->sg) < R592_LFIFO_SIZE) {
297 		message("problem in dma_map_sg");
298 		return -EIO;
299 	}
300 
301 	r592_start_dma(dev, is_write);
302 
303 	/* Wait for DMA completion */
304 	if (!wait_for_completion_timeout(
305 			&dev->dma_done, msecs_to_jiffies(1000))) {
306 		message("DMA timeout");
307 		r592_stop_dma(dev, -ETIMEDOUT);
308 	}
309 
310 	dma_unmap_sg(&dev->pci_dev->dev, &dev->req->sg, 1, is_write ?
311 		     DMA_TO_DEVICE : DMA_FROM_DEVICE);
312 
313 	return dev->dma_error;
314 }
315 
316 /*
317  * Writes the FIFO in 4 byte chunks.
318  * If length isn't 4 byte aligned, rest of the data if put to a fifo
319  * to be written later
320  * Use r592_flush_fifo_write to flush that fifo when writing for the
321  * last time
322  */
323 static void r592_write_fifo_pio(struct r592_device *dev,
324 					unsigned char *buffer, int len)
325 {
326 	/* flush spill from former write */
327 	if (!kfifo_is_empty(&dev->pio_fifo)) {
328 
329 		u8 tmp[4] = {0};
330 		int copy_len = kfifo_in(&dev->pio_fifo, buffer, len);
331 
332 		if (!kfifo_is_full(&dev->pio_fifo))
333 			return;
334 		len -= copy_len;
335 		buffer += copy_len;
336 
337 		copy_len = kfifo_out(&dev->pio_fifo, tmp, 4);
338 		WARN_ON(copy_len != 4);
339 		r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)tmp);
340 	}
341 
342 	WARN_ON(!kfifo_is_empty(&dev->pio_fifo));
343 
344 	/* write full dwords */
345 	while (len >= 4) {
346 		r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)buffer);
347 		buffer += 4;
348 		len -= 4;
349 	}
350 
351 	/* put remaining bytes to the spill */
352 	if (len)
353 		kfifo_in(&dev->pio_fifo, buffer, len);
354 }
355 
356 /* Flushes the temporary FIFO used to make aligned DWORD writes */
357 static void r592_flush_fifo_write(struct r592_device *dev)
358 {
359 	int ret;
360 	u8 buffer[4] = { 0 };
361 
362 	if (kfifo_is_empty(&dev->pio_fifo))
363 		return;
364 
365 	ret = kfifo_out(&dev->pio_fifo, buffer, 4);
366 	/* intentionally ignore __must_check return code */
367 	(void)ret;
368 	r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)buffer);
369 }
370 
371 /*
372  * Read a fifo in 4 bytes chunks.
373  * If input doesn't fit the buffer, it places bytes of last dword in spill
374  * buffer, so that they don't get lost on last read, just throw these away.
375  */
376 static void r592_read_fifo_pio(struct r592_device *dev,
377 						unsigned char *buffer, int len)
378 {
379 	u8 tmp[4];
380 
381 	/* Read from last spill */
382 	if (!kfifo_is_empty(&dev->pio_fifo)) {
383 		int bytes_copied =
384 			kfifo_out(&dev->pio_fifo, buffer, min(4, len));
385 		buffer += bytes_copied;
386 		len -= bytes_copied;
387 
388 		if (!kfifo_is_empty(&dev->pio_fifo))
389 			return;
390 	}
391 
392 	/* Reads dwords from FIFO */
393 	while (len >= 4) {
394 		*(u32 *)buffer = r592_read_reg_raw_be(dev, R592_FIFO_PIO);
395 		buffer += 4;
396 		len -= 4;
397 	}
398 
399 	if (len) {
400 		*(u32 *)tmp = r592_read_reg_raw_be(dev, R592_FIFO_PIO);
401 		kfifo_in(&dev->pio_fifo, tmp, 4);
402 		len -= kfifo_out(&dev->pio_fifo, buffer, len);
403 	}
404 
405 	WARN_ON(len);
406 	return;
407 }
408 
409 /* Transfers actual data using PIO. */
410 static int r592_transfer_fifo_pio(struct r592_device *dev)
411 {
412 	unsigned long flags;
413 
414 	bool is_write = dev->req->tpc >= MS_TPC_SET_RW_REG_ADRS;
415 	struct sg_mapping_iter miter;
416 
417 	kfifo_reset(&dev->pio_fifo);
418 
419 	if (!dev->req->long_data) {
420 		if (is_write) {
421 			r592_write_fifo_pio(dev, dev->req->data,
422 							dev->req->data_len);
423 			r592_flush_fifo_write(dev);
424 		} else
425 			r592_read_fifo_pio(dev, dev->req->data,
426 							dev->req->data_len);
427 		return 0;
428 	}
429 
430 	local_irq_save(flags);
431 	sg_miter_start(&miter, &dev->req->sg, 1, SG_MITER_ATOMIC |
432 		(is_write ? SG_MITER_FROM_SG : SG_MITER_TO_SG));
433 
434 	/* Do the transfer fifo<->memory*/
435 	while (sg_miter_next(&miter))
436 		if (is_write)
437 			r592_write_fifo_pio(dev, miter.addr, miter.length);
438 		else
439 			r592_read_fifo_pio(dev, miter.addr, miter.length);
440 
441 
442 	/* Write last few non aligned bytes*/
443 	if (is_write)
444 		r592_flush_fifo_write(dev);
445 
446 	sg_miter_stop(&miter);
447 	local_irq_restore(flags);
448 	return 0;
449 }
450 
451 /* Executes one TPC (data is read/written from small or large fifo) */
452 static void r592_execute_tpc(struct r592_device *dev)
453 {
454 	bool is_write;
455 	int len, error;
456 	u32 status, reg;
457 
458 	if (!dev->req) {
459 		message("BUG: tpc execution without request!");
460 		return;
461 	}
462 
463 	is_write = dev->req->tpc >= MS_TPC_SET_RW_REG_ADRS;
464 	len = dev->req->long_data ?
465 		dev->req->sg.length : dev->req->data_len;
466 
467 	/* Ensure that FIFO can hold the input data */
468 	if (len > R592_LFIFO_SIZE) {
469 		message("IO: hardware doesn't support TPCs longer that 512");
470 		error = -ENOSYS;
471 		goto out;
472 	}
473 
474 	if (!(r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_PRSNT)) {
475 		dbg("IO: refusing to send TPC because card is absent");
476 		error = -ENODEV;
477 		goto out;
478 	}
479 
480 	dbg("IO: executing %s LEN=%d",
481 			memstick_debug_get_tpc_name(dev->req->tpc), len);
482 
483 	/* Set IO direction */
484 	if (is_write)
485 		r592_set_reg_mask(dev, R592_IO, R592_IO_DIRECTION);
486 	else
487 		r592_clear_reg_mask(dev, R592_IO, R592_IO_DIRECTION);
488 
489 
490 	error = r592_test_fifo_empty(dev);
491 	if (error)
492 		goto out;
493 
494 	/* Transfer write data */
495 	if (is_write) {
496 		error = r592_transfer_fifo_dma(dev);
497 		if (error == -EINVAL)
498 			error = r592_transfer_fifo_pio(dev);
499 	}
500 
501 	if (error)
502 		goto out;
503 
504 	/* Trigger the TPC */
505 	reg = (len << R592_TPC_EXEC_LEN_SHIFT) |
506 		(dev->req->tpc << R592_TPC_EXEC_TPC_SHIFT) |
507 			R592_TPC_EXEC_BIG_FIFO;
508 
509 	r592_write_reg(dev, R592_TPC_EXEC, reg);
510 
511 	/* Wait for TPC completion */
512 	status = R592_STATUS_RDY;
513 	if (dev->req->need_card_int)
514 		status |= R592_STATUS_CED;
515 
516 	error = r592_wait_status(dev, status, status);
517 	if (error) {
518 		message("card didn't respond");
519 		goto out;
520 	}
521 
522 	/* Test IO errors */
523 	error = r592_test_io_error(dev);
524 	if (error) {
525 		dbg("IO error");
526 		goto out;
527 	}
528 
529 	/* Read data from FIFO */
530 	if (!is_write) {
531 		error = r592_transfer_fifo_dma(dev);
532 		if (error == -EINVAL)
533 			error = r592_transfer_fifo_pio(dev);
534 	}
535 
536 	/* read INT reg. This can be shortened with shifts, but that way
537 		its more readable */
538 	if (dev->parallel_mode && dev->req->need_card_int) {
539 
540 		dev->req->int_reg = 0;
541 		status = r592_read_reg(dev, R592_STATUS);
542 
543 		if (status & R592_STATUS_P_CMDNACK)
544 			dev->req->int_reg |= MEMSTICK_INT_CMDNAK;
545 		if (status & R592_STATUS_P_BREQ)
546 			dev->req->int_reg |= MEMSTICK_INT_BREQ;
547 		if (status & R592_STATUS_P_INTERR)
548 			dev->req->int_reg |= MEMSTICK_INT_ERR;
549 		if (status & R592_STATUS_P_CED)
550 			dev->req->int_reg |= MEMSTICK_INT_CED;
551 	}
552 
553 	if (error)
554 		dbg("FIFO read error");
555 out:
556 	dev->req->error = error;
557 	r592_clear_reg_mask(dev, R592_REG_MSC, R592_REG_MSC_LED);
558 	return;
559 }
560 
561 /* Main request processing thread */
562 static int r592_process_thread(void *data)
563 {
564 	int error;
565 	struct r592_device *dev = (struct r592_device *)data;
566 	unsigned long flags;
567 
568 	while (!kthread_should_stop()) {
569 		spin_lock_irqsave(&dev->io_thread_lock, flags);
570 		set_current_state(TASK_INTERRUPTIBLE);
571 		error = memstick_next_req(dev->host, &dev->req);
572 		spin_unlock_irqrestore(&dev->io_thread_lock, flags);
573 
574 		if (error) {
575 			if (error == -ENXIO || error == -EAGAIN) {
576 				dbg_verbose("IO: done IO, sleeping");
577 			} else {
578 				dbg("IO: unknown error from "
579 					"memstick_next_req %d", error);
580 			}
581 
582 			if (kthread_should_stop())
583 				set_current_state(TASK_RUNNING);
584 
585 			schedule();
586 		} else {
587 			set_current_state(TASK_RUNNING);
588 			r592_execute_tpc(dev);
589 		}
590 	}
591 	return 0;
592 }
593 
594 /* Reprogram chip to detect change in card state */
595 /* eg, if card is detected, arm it to detect removal, and vice versa */
596 static void r592_update_card_detect(struct r592_device *dev)
597 {
598 	u32 reg = r592_read_reg(dev, R592_REG_MSC);
599 	bool card_detected = reg & R592_REG_MSC_PRSNT;
600 
601 	dbg("update card detect. card state: %s", card_detected ?
602 		"present" : "absent");
603 
604 	reg &= ~((R592_REG_MSC_IRQ_REMOVE | R592_REG_MSC_IRQ_INSERT) << 16);
605 
606 	if (card_detected)
607 		reg |= (R592_REG_MSC_IRQ_REMOVE << 16);
608 	else
609 		reg |= (R592_REG_MSC_IRQ_INSERT << 16);
610 
611 	r592_write_reg(dev, R592_REG_MSC, reg);
612 }
613 
614 /* Timer routine that fires 1 second after last card detection event, */
615 static void r592_detect_timer(struct timer_list *t)
616 {
617 	struct r592_device *dev = from_timer(dev, t, detect_timer);
618 	r592_update_card_detect(dev);
619 	memstick_detect_change(dev->host);
620 }
621 
622 /* Interrupt handler */
623 static irqreturn_t r592_irq(int irq, void *data)
624 {
625 	struct r592_device *dev = (struct r592_device *)data;
626 	irqreturn_t ret = IRQ_NONE;
627 	u32 reg;
628 	u16 irq_enable, irq_status;
629 	unsigned long flags;
630 	int error;
631 
632 	spin_lock_irqsave(&dev->irq_lock, flags);
633 
634 	reg = r592_read_reg(dev, R592_REG_MSC);
635 	irq_enable = reg >> 16;
636 	irq_status = reg & 0xFFFF;
637 
638 	/* Ack the interrupts */
639 	reg &= ~irq_status;
640 	r592_write_reg(dev, R592_REG_MSC, reg);
641 
642 	/* Get the IRQ status minus bits that aren't enabled */
643 	irq_status &= (irq_enable);
644 
645 	/* Due to limitation of memstick core, we don't look at bits that
646 		indicate that card was removed/inserted and/or present */
647 	if (irq_status & (R592_REG_MSC_IRQ_INSERT | R592_REG_MSC_IRQ_REMOVE)) {
648 
649 		bool card_was_added = irq_status & R592_REG_MSC_IRQ_INSERT;
650 		ret = IRQ_HANDLED;
651 
652 		message("IRQ: card %s", card_was_added ? "added" : "removed");
653 
654 		mod_timer(&dev->detect_timer,
655 			jiffies + msecs_to_jiffies(card_was_added ? 500 : 50));
656 	}
657 
658 	if (irq_status &
659 		(R592_REG_MSC_FIFO_DMA_DONE | R592_REG_MSC_FIFO_DMA_ERR)) {
660 		ret = IRQ_HANDLED;
661 
662 		if (irq_status & R592_REG_MSC_FIFO_DMA_ERR) {
663 			message("IRQ: DMA error");
664 			error = -EIO;
665 		} else {
666 			dbg_verbose("IRQ: dma done");
667 			error = 0;
668 		}
669 
670 		r592_stop_dma(dev, error);
671 		complete(&dev->dma_done);
672 	}
673 
674 	spin_unlock_irqrestore(&dev->irq_lock, flags);
675 	return ret;
676 }
677 
678 /* External inteface: set settings */
679 static int r592_set_param(struct memstick_host *host,
680 			enum memstick_param param, int value)
681 {
682 	struct r592_device *dev = memstick_priv(host);
683 
684 	switch (param) {
685 	case MEMSTICK_POWER:
686 		switch (value) {
687 		case MEMSTICK_POWER_ON:
688 			return r592_enable_device(dev, true);
689 		case MEMSTICK_POWER_OFF:
690 			return r592_enable_device(dev, false);
691 		default:
692 			return -EINVAL;
693 		}
694 	case MEMSTICK_INTERFACE:
695 		switch (value) {
696 		case MEMSTICK_SERIAL:
697 			return r592_set_mode(dev, 0);
698 		case MEMSTICK_PAR4:
699 			return r592_set_mode(dev, 1);
700 		default:
701 			return -EINVAL;
702 		}
703 	default:
704 		return -EINVAL;
705 	}
706 }
707 
708 /* External interface: submit requests */
709 static void r592_submit_req(struct memstick_host *host)
710 {
711 	struct r592_device *dev = memstick_priv(host);
712 	unsigned long flags;
713 
714 	if (dev->req)
715 		return;
716 
717 	spin_lock_irqsave(&dev->io_thread_lock, flags);
718 	if (wake_up_process(dev->io_thread))
719 		dbg_verbose("IO thread woken to process requests");
720 	spin_unlock_irqrestore(&dev->io_thread_lock, flags);
721 }
722 
723 static const struct pci_device_id r592_pci_id_tbl[] = {
724 
725 	{ PCI_VDEVICE(RICOH, 0x0592), },
726 	{ },
727 };
728 
729 /* Main entry */
730 static int r592_probe(struct pci_dev *pdev, const struct pci_device_id *id)
731 {
732 	int error = -ENOMEM;
733 	struct memstick_host *host;
734 	struct r592_device *dev;
735 
736 	/* Allocate memory */
737 	host = memstick_alloc_host(sizeof(struct r592_device), &pdev->dev);
738 	if (!host)
739 		goto error1;
740 
741 	dev = memstick_priv(host);
742 	dev->host = host;
743 	dev->pci_dev = pdev;
744 	pci_set_drvdata(pdev, dev);
745 
746 	/* pci initialization */
747 	error = pci_enable_device(pdev);
748 	if (error)
749 		goto error2;
750 
751 	pci_set_master(pdev);
752 	error = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
753 	if (error)
754 		goto error3;
755 
756 	error = pci_request_regions(pdev, DRV_NAME);
757 	if (error)
758 		goto error3;
759 
760 	dev->mmio = pci_ioremap_bar(pdev, 0);
761 	if (!dev->mmio) {
762 		error = -ENOMEM;
763 		goto error4;
764 	}
765 
766 	dev->irq = pdev->irq;
767 	spin_lock_init(&dev->irq_lock);
768 	spin_lock_init(&dev->io_thread_lock);
769 	init_completion(&dev->dma_done);
770 	INIT_KFIFO(dev->pio_fifo);
771 	timer_setup(&dev->detect_timer, r592_detect_timer, 0);
772 
773 	/* Host initialization */
774 	host->caps = MEMSTICK_CAP_PAR4;
775 	host->request = r592_submit_req;
776 	host->set_param = r592_set_param;
777 	r592_check_dma(dev);
778 
779 	dev->io_thread = kthread_run(r592_process_thread, dev, "r592_io");
780 	if (IS_ERR(dev->io_thread)) {
781 		error = PTR_ERR(dev->io_thread);
782 		goto error5;
783 	}
784 
785 	/* This is just a precation, so don't fail */
786 	dev->dummy_dma_page = dma_alloc_coherent(&pdev->dev, PAGE_SIZE,
787 		&dev->dummy_dma_page_physical_address, GFP_KERNEL);
788 	r592_stop_dma(dev , 0);
789 
790 	error = request_irq(dev->irq, &r592_irq, IRQF_SHARED,
791 			  DRV_NAME, dev);
792 	if (error)
793 		goto error6;
794 
795 	r592_update_card_detect(dev);
796 	error = memstick_add_host(host);
797 	if (error)
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 		dma_free_coherent(&pdev->dev, 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 	del_timer_sync(&dev->detect_timer);
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 	if (dev->dummy_dma_page)
840 		dma_free_coherent(&pdev->dev, PAGE_SIZE, dev->dummy_dma_page,
841 			dev->dummy_dma_page_physical_address);
842 
843 	free_irq(dev->irq, dev);
844 	iounmap(dev->mmio);
845 	pci_release_regions(pdev);
846 	pci_disable_device(pdev);
847 	memstick_free_host(dev->host);
848 }
849 
850 #ifdef CONFIG_PM_SLEEP
851 static int r592_suspend(struct device *core_dev)
852 {
853 	struct r592_device *dev = dev_get_drvdata(core_dev);
854 
855 	r592_clear_interrupts(dev);
856 	memstick_suspend_host(dev->host);
857 	del_timer_sync(&dev->detect_timer);
858 	return 0;
859 }
860 
861 static int r592_resume(struct device *core_dev)
862 {
863 	struct r592_device *dev = dev_get_drvdata(core_dev);
864 
865 	r592_clear_interrupts(dev);
866 	r592_enable_device(dev, false);
867 	memstick_resume_host(dev->host);
868 	r592_update_card_detect(dev);
869 	return 0;
870 }
871 #endif
872 
873 static SIMPLE_DEV_PM_OPS(r592_pm_ops, r592_suspend, r592_resume);
874 
875 MODULE_DEVICE_TABLE(pci, r592_pci_id_tbl);
876 
877 static struct pci_driver r592_pci_driver = {
878 	.name		= DRV_NAME,
879 	.id_table	= r592_pci_id_tbl,
880 	.probe		= r592_probe,
881 	.remove		= r592_remove,
882 	.driver.pm	= &r592_pm_ops,
883 };
884 
885 module_pci_driver(r592_pci_driver);
886 
887 module_param_named(enable_dma, r592_enable_dma, bool, S_IRUGO);
888 MODULE_PARM_DESC(enable_dma, "Enable usage of the DMA (default)");
889 module_param(debug, int, S_IRUGO | S_IWUSR);
890 MODULE_PARM_DESC(debug, "Debug level (0-3)");
891 
892 MODULE_LICENSE("GPL");
893 MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
894 MODULE_DESCRIPTION("Ricoh R5C592 Memstick/Memstick PRO card reader driver");
895