Linux 6.9-rc1
[linux-2.6-microblaze.git] / drivers / mtd / nand / raw / r852.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright © 2009 - Maxim Levitsky
4  * driver for Ricoh xD readers
5  */
6
7 #define DRV_NAME "r852"
8 #define pr_fmt(fmt)  DRV_NAME ": " fmt
9
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/jiffies.h>
13 #include <linux/workqueue.h>
14 #include <linux/interrupt.h>
15 #include <linux/pci.h>
16 #include <linux/pci_ids.h>
17 #include <linux/delay.h>
18 #include <linux/slab.h>
19 #include <asm/byteorder.h>
20 #include <linux/sched.h>
21 #include "sm_common.h"
22 #include "r852.h"
23
24
25 static bool r852_enable_dma = 1;
26 module_param(r852_enable_dma, bool, S_IRUGO);
27 MODULE_PARM_DESC(r852_enable_dma, "Enable usage of the DMA (default)");
28
29 static int debug;
30 module_param(debug, int, S_IRUGO | S_IWUSR);
31 MODULE_PARM_DESC(debug, "Debug level (0-2)");
32
33 /* read register */
34 static inline uint8_t r852_read_reg(struct r852_device *dev, int address)
35 {
36         uint8_t reg = readb(dev->mmio + address);
37         return reg;
38 }
39
40 /* write register */
41 static inline void r852_write_reg(struct r852_device *dev,
42                                                 int address, uint8_t value)
43 {
44         writeb(value, dev->mmio + address);
45 }
46
47
48 /* read dword sized register */
49 static inline uint32_t r852_read_reg_dword(struct r852_device *dev, int address)
50 {
51         uint32_t reg = le32_to_cpu(readl(dev->mmio + address));
52         return reg;
53 }
54
55 /* write dword sized register */
56 static inline void r852_write_reg_dword(struct r852_device *dev,
57                                                         int address, uint32_t value)
58 {
59         writel(cpu_to_le32(value), dev->mmio + address);
60 }
61
62 /* returns pointer to our private structure */
63 static inline struct r852_device *r852_get_dev(struct mtd_info *mtd)
64 {
65         struct nand_chip *chip = mtd_to_nand(mtd);
66         return nand_get_controller_data(chip);
67 }
68
69
70 /* check if controller supports dma */
71 static void r852_dma_test(struct r852_device *dev)
72 {
73         dev->dma_usable = (r852_read_reg(dev, R852_DMA_CAP) &
74                 (R852_DMA1 | R852_DMA2)) == (R852_DMA1 | R852_DMA2);
75
76         if (!dev->dma_usable)
77                 message("Non dma capable device detected, dma disabled");
78
79         if (!r852_enable_dma) {
80                 message("disabling dma on user request");
81                 dev->dma_usable = 0;
82         }
83 }
84
85 /*
86  * Enable dma. Enables ether first or second stage of the DMA,
87  * Expects dev->dma_dir and dev->dma_state be set
88  */
89 static void r852_dma_enable(struct r852_device *dev)
90 {
91         uint8_t dma_reg, dma_irq_reg;
92
93         /* Set up dma settings */
94         dma_reg = r852_read_reg_dword(dev, R852_DMA_SETTINGS);
95         dma_reg &= ~(R852_DMA_READ | R852_DMA_INTERNAL | R852_DMA_MEMORY);
96
97         if (dev->dma_dir)
98                 dma_reg |= R852_DMA_READ;
99
100         if (dev->dma_state == DMA_INTERNAL) {
101                 dma_reg |= R852_DMA_INTERNAL;
102                 /* Precaution to make sure HW doesn't write */
103                         /* to random kernel memory */
104                 r852_write_reg_dword(dev, R852_DMA_ADDR,
105                         cpu_to_le32(dev->phys_bounce_buffer));
106         } else {
107                 dma_reg |= R852_DMA_MEMORY;
108                 r852_write_reg_dword(dev, R852_DMA_ADDR,
109                         cpu_to_le32(dev->phys_dma_addr));
110         }
111
112         /* Precaution: make sure write reached the device */
113         r852_read_reg_dword(dev, R852_DMA_ADDR);
114
115         r852_write_reg_dword(dev, R852_DMA_SETTINGS, dma_reg);
116
117         /* Set dma irq */
118         dma_irq_reg = r852_read_reg_dword(dev, R852_DMA_IRQ_ENABLE);
119         r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE,
120                 dma_irq_reg |
121                 R852_DMA_IRQ_INTERNAL |
122                 R852_DMA_IRQ_ERROR |
123                 R852_DMA_IRQ_MEMORY);
124 }
125
126 /*
127  * Disable dma, called from the interrupt handler, which specifies
128  * success of the operation via 'error' argument
129  */
130 static void r852_dma_done(struct r852_device *dev, int error)
131 {
132         WARN_ON(dev->dma_stage == 0);
133
134         r852_write_reg_dword(dev, R852_DMA_IRQ_STA,
135                         r852_read_reg_dword(dev, R852_DMA_IRQ_STA));
136
137         r852_write_reg_dword(dev, R852_DMA_SETTINGS, 0);
138         r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE, 0);
139
140         /* Precaution to make sure HW doesn't write to random kernel memory */
141         r852_write_reg_dword(dev, R852_DMA_ADDR,
142                 cpu_to_le32(dev->phys_bounce_buffer));
143         r852_read_reg_dword(dev, R852_DMA_ADDR);
144
145         dev->dma_error = error;
146         dev->dma_stage = 0;
147
148         if (dev->phys_dma_addr && dev->phys_dma_addr != dev->phys_bounce_buffer)
149                 dma_unmap_single(&dev->pci_dev->dev, dev->phys_dma_addr,
150                         R852_DMA_LEN,
151                         dev->dma_dir ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
152 }
153
154 /*
155  * Wait, till dma is done, which includes both phases of it
156  */
157 static int r852_dma_wait(struct r852_device *dev)
158 {
159         long timeout = wait_for_completion_timeout(&dev->dma_done,
160                                 msecs_to_jiffies(1000));
161         if (!timeout) {
162                 dbg("timeout waiting for DMA interrupt");
163                 return -ETIMEDOUT;
164         }
165
166         return 0;
167 }
168
169 /*
170  * Read/Write one page using dma. Only pages can be read (512 bytes)
171 */
172 static void r852_do_dma(struct r852_device *dev, uint8_t *buf, int do_read)
173 {
174         int bounce = 0;
175         unsigned long flags;
176         int error;
177
178         dev->dma_error = 0;
179
180         /* Set dma direction */
181         dev->dma_dir = do_read;
182         dev->dma_stage = 1;
183         reinit_completion(&dev->dma_done);
184
185         dbg_verbose("doing dma %s ", do_read ? "read" : "write");
186
187         /* Set initial dma state: for reading first fill on board buffer,
188           from device, for writes first fill the buffer  from memory*/
189         dev->dma_state = do_read ? DMA_INTERNAL : DMA_MEMORY;
190
191         /* if incoming buffer is not page aligned, we should do bounce */
192         if ((unsigned long)buf & (R852_DMA_LEN-1))
193                 bounce = 1;
194
195         if (!bounce) {
196                 dev->phys_dma_addr = dma_map_single(&dev->pci_dev->dev, buf,
197                         R852_DMA_LEN,
198                         do_read ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
199                 if (dma_mapping_error(&dev->pci_dev->dev, dev->phys_dma_addr))
200                         bounce = 1;
201         }
202
203         if (bounce) {
204                 dbg_verbose("dma: using bounce buffer");
205                 dev->phys_dma_addr = dev->phys_bounce_buffer;
206                 if (!do_read)
207                         memcpy(dev->bounce_buffer, buf, R852_DMA_LEN);
208         }
209
210         /* Enable DMA */
211         spin_lock_irqsave(&dev->irqlock, flags);
212         r852_dma_enable(dev);
213         spin_unlock_irqrestore(&dev->irqlock, flags);
214
215         /* Wait till complete */
216         error = r852_dma_wait(dev);
217
218         if (error) {
219                 r852_dma_done(dev, error);
220                 return;
221         }
222
223         if (do_read && bounce)
224                 memcpy((void *)buf, dev->bounce_buffer, R852_DMA_LEN);
225 }
226
227 /*
228  * Program data lines of the nand chip to send data to it
229  */
230 static void r852_write_buf(struct nand_chip *chip, const uint8_t *buf, int len)
231 {
232         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
233         uint32_t reg;
234
235         /* Don't allow any access to hardware if we suspect card removal */
236         if (dev->card_unstable)
237                 return;
238
239         /* Special case for whole sector read */
240         if (len == R852_DMA_LEN && dev->dma_usable) {
241                 r852_do_dma(dev, (uint8_t *)buf, 0);
242                 return;
243         }
244
245         /* write DWORD chinks - faster */
246         while (len >= 4) {
247                 reg = buf[0] | buf[1] << 8 | buf[2] << 16 | buf[3] << 24;
248                 r852_write_reg_dword(dev, R852_DATALINE, reg);
249                 buf += 4;
250                 len -= 4;
251
252         }
253
254         /* write rest */
255         while (len > 0) {
256                 r852_write_reg(dev, R852_DATALINE, *buf++);
257                 len--;
258         }
259 }
260
261 /*
262  * Read data lines of the nand chip to retrieve data
263  */
264 static void r852_read_buf(struct nand_chip *chip, uint8_t *buf, int len)
265 {
266         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
267         uint32_t reg;
268
269         if (dev->card_unstable) {
270                 /* since we can't signal error here, at least, return
271                         predictable buffer */
272                 memset(buf, 0, len);
273                 return;
274         }
275
276         /* special case for whole sector read */
277         if (len == R852_DMA_LEN && dev->dma_usable) {
278                 r852_do_dma(dev, buf, 1);
279                 return;
280         }
281
282         /* read in dword sized chunks */
283         while (len >= 4) {
284
285                 reg = r852_read_reg_dword(dev, R852_DATALINE);
286                 *buf++ = reg & 0xFF;
287                 *buf++ = (reg >> 8) & 0xFF;
288                 *buf++ = (reg >> 16) & 0xFF;
289                 *buf++ = (reg >> 24) & 0xFF;
290                 len -= 4;
291         }
292
293         /* read the reset by bytes */
294         while (len--)
295                 *buf++ = r852_read_reg(dev, R852_DATALINE);
296 }
297
298 /*
299  * Read one byte from nand chip
300  */
301 static uint8_t r852_read_byte(struct nand_chip *chip)
302 {
303         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
304
305         /* Same problem as in r852_read_buf.... */
306         if (dev->card_unstable)
307                 return 0;
308
309         return r852_read_reg(dev, R852_DATALINE);
310 }
311
312 /*
313  * Control several chip lines & send commands
314  */
315 static void r852_cmdctl(struct nand_chip *chip, int dat, unsigned int ctrl)
316 {
317         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
318
319         if (dev->card_unstable)
320                 return;
321
322         if (ctrl & NAND_CTRL_CHANGE) {
323
324                 dev->ctlreg &= ~(R852_CTL_DATA | R852_CTL_COMMAND |
325                                  R852_CTL_ON | R852_CTL_CARDENABLE);
326
327                 if (ctrl & NAND_ALE)
328                         dev->ctlreg |= R852_CTL_DATA;
329
330                 if (ctrl & NAND_CLE)
331                         dev->ctlreg |= R852_CTL_COMMAND;
332
333                 if (ctrl & NAND_NCE)
334                         dev->ctlreg |= (R852_CTL_CARDENABLE | R852_CTL_ON);
335                 else
336                         dev->ctlreg &= ~R852_CTL_WRITE;
337
338                 /* when write is stareted, enable write access */
339                 if (dat == NAND_CMD_ERASE1)
340                         dev->ctlreg |= R852_CTL_WRITE;
341
342                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
343         }
344
345          /* HACK: NAND_CMD_SEQIN is called without NAND_CTRL_CHANGE, but we need
346                 to set write mode */
347         if (dat == NAND_CMD_SEQIN && (dev->ctlreg & R852_CTL_COMMAND)) {
348                 dev->ctlreg |= R852_CTL_WRITE;
349                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
350         }
351
352         if (dat != NAND_CMD_NONE)
353                 r852_write_reg(dev, R852_DATALINE, dat);
354 }
355
356 /*
357  * Wait till card is ready.
358  * based on nand_wait, but returns errors on DMA error
359  */
360 static int r852_wait(struct nand_chip *chip)
361 {
362         struct r852_device *dev = nand_get_controller_data(chip);
363
364         unsigned long timeout;
365         u8 status;
366
367         timeout = jiffies + msecs_to_jiffies(400);
368
369         while (time_before(jiffies, timeout))
370                 if (chip->legacy.dev_ready(chip))
371                         break;
372
373         nand_status_op(chip, &status);
374
375         /* Unfortunelly, no way to send detailed error status... */
376         if (dev->dma_error) {
377                 status |= NAND_STATUS_FAIL;
378                 dev->dma_error = 0;
379         }
380         return status;
381 }
382
383 /*
384  * Check if card is ready
385  */
386
387 static int r852_ready(struct nand_chip *chip)
388 {
389         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
390         return !(r852_read_reg(dev, R852_CARD_STA) & R852_CARD_STA_BUSY);
391 }
392
393
394 /*
395  * Set ECC engine mode
396 */
397
398 static void r852_ecc_hwctl(struct nand_chip *chip, int mode)
399 {
400         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
401
402         if (dev->card_unstable)
403                 return;
404
405         switch (mode) {
406         case NAND_ECC_READ:
407         case NAND_ECC_WRITE:
408                 /* enable ecc generation/check*/
409                 dev->ctlreg |= R852_CTL_ECC_ENABLE;
410
411                 /* flush ecc buffer */
412                 r852_write_reg(dev, R852_CTL,
413                         dev->ctlreg | R852_CTL_ECC_ACCESS);
414
415                 r852_read_reg_dword(dev, R852_DATALINE);
416                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
417                 return;
418
419         case NAND_ECC_READSYN:
420                 /* disable ecc generation */
421                 dev->ctlreg &= ~R852_CTL_ECC_ENABLE;
422                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
423         }
424 }
425
426 /*
427  * Calculate ECC, only used for writes
428  */
429
430 static int r852_ecc_calculate(struct nand_chip *chip, const uint8_t *dat,
431                               uint8_t *ecc_code)
432 {
433         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
434         struct sm_oob *oob = (struct sm_oob *)ecc_code;
435         uint32_t ecc1, ecc2;
436
437         if (dev->card_unstable)
438                 return 0;
439
440         dev->ctlreg &= ~R852_CTL_ECC_ENABLE;
441         r852_write_reg(dev, R852_CTL, dev->ctlreg | R852_CTL_ECC_ACCESS);
442
443         ecc1 = r852_read_reg_dword(dev, R852_DATALINE);
444         ecc2 = r852_read_reg_dword(dev, R852_DATALINE);
445
446         oob->ecc1[0] = (ecc1) & 0xFF;
447         oob->ecc1[1] = (ecc1 >> 8) & 0xFF;
448         oob->ecc1[2] = (ecc1 >> 16) & 0xFF;
449
450         oob->ecc2[0] = (ecc2) & 0xFF;
451         oob->ecc2[1] = (ecc2 >> 8) & 0xFF;
452         oob->ecc2[2] = (ecc2 >> 16) & 0xFF;
453
454         r852_write_reg(dev, R852_CTL, dev->ctlreg);
455         return 0;
456 }
457
458 /*
459  * Correct the data using ECC, hw did almost everything for us
460  */
461
462 static int r852_ecc_correct(struct nand_chip *chip, uint8_t *dat,
463                             uint8_t *read_ecc, uint8_t *calc_ecc)
464 {
465         uint32_t ecc_reg;
466         uint8_t ecc_status, err_byte;
467         int i, error = 0;
468
469         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
470
471         if (dev->card_unstable)
472                 return 0;
473
474         if (dev->dma_error) {
475                 dev->dma_error = 0;
476                 return -EIO;
477         }
478
479         r852_write_reg(dev, R852_CTL, dev->ctlreg | R852_CTL_ECC_ACCESS);
480         ecc_reg = r852_read_reg_dword(dev, R852_DATALINE);
481         r852_write_reg(dev, R852_CTL, dev->ctlreg);
482
483         for (i = 0 ; i <= 1 ; i++) {
484
485                 ecc_status = (ecc_reg >> 8) & 0xFF;
486
487                 /* ecc uncorrectable error */
488                 if (ecc_status & R852_ECC_FAIL) {
489                         dbg("ecc: unrecoverable error, in half %d", i);
490                         error = -EBADMSG;
491                         goto exit;
492                 }
493
494                 /* correctable error */
495                 if (ecc_status & R852_ECC_CORRECTABLE) {
496
497                         err_byte = ecc_reg & 0xFF;
498                         dbg("ecc: recoverable error, "
499                                 "in half %d, byte %d, bit %d", i,
500                                 err_byte, ecc_status & R852_ECC_ERR_BIT_MSK);
501
502                         dat[err_byte] ^=
503                                 1 << (ecc_status & R852_ECC_ERR_BIT_MSK);
504                         error++;
505                 }
506
507                 dat += 256;
508                 ecc_reg >>= 16;
509         }
510 exit:
511         return error;
512 }
513
514 /*
515  * This is copy of nand_read_oob_std
516  * nand_read_oob_syndrome assumes we can send column address - we can't
517  */
518 static int r852_read_oob(struct nand_chip *chip, int page)
519 {
520         struct mtd_info *mtd = nand_to_mtd(chip);
521
522         return nand_read_oob_op(chip, page, 0, chip->oob_poi, mtd->oobsize);
523 }
524
525 /*
526  * Start the nand engine
527  */
528
529 static void r852_engine_enable(struct r852_device *dev)
530 {
531         if (r852_read_reg_dword(dev, R852_HW) & R852_HW_UNKNOWN) {
532                 r852_write_reg(dev, R852_CTL, R852_CTL_RESET | R852_CTL_ON);
533                 r852_write_reg_dword(dev, R852_HW, R852_HW_ENABLED);
534         } else {
535                 r852_write_reg_dword(dev, R852_HW, R852_HW_ENABLED);
536                 r852_write_reg(dev, R852_CTL, R852_CTL_RESET | R852_CTL_ON);
537         }
538         msleep(300);
539         r852_write_reg(dev, R852_CTL, 0);
540 }
541
542
543 /*
544  * Stop the nand engine
545  */
546
547 static void r852_engine_disable(struct r852_device *dev)
548 {
549         r852_write_reg_dword(dev, R852_HW, 0);
550         r852_write_reg(dev, R852_CTL, R852_CTL_RESET);
551 }
552
553 /*
554  * Test if card is present
555  */
556
557 static void r852_card_update_present(struct r852_device *dev)
558 {
559         unsigned long flags;
560         uint8_t reg;
561
562         spin_lock_irqsave(&dev->irqlock, flags);
563         reg = r852_read_reg(dev, R852_CARD_STA);
564         dev->card_detected = !!(reg & R852_CARD_STA_PRESENT);
565         spin_unlock_irqrestore(&dev->irqlock, flags);
566 }
567
568 /*
569  * Update card detection IRQ state according to current card state
570  * which is read in r852_card_update_present
571  */
572 static void r852_update_card_detect(struct r852_device *dev)
573 {
574         int card_detect_reg = r852_read_reg(dev, R852_CARD_IRQ_ENABLE);
575         dev->card_unstable = 0;
576
577         card_detect_reg &= ~(R852_CARD_IRQ_REMOVE | R852_CARD_IRQ_INSERT);
578         card_detect_reg |= R852_CARD_IRQ_GENABLE;
579
580         card_detect_reg |= dev->card_detected ?
581                 R852_CARD_IRQ_REMOVE : R852_CARD_IRQ_INSERT;
582
583         r852_write_reg(dev, R852_CARD_IRQ_ENABLE, card_detect_reg);
584 }
585
586 static ssize_t media_type_show(struct device *sys_dev,
587                                struct device_attribute *attr, char *buf)
588 {
589         struct mtd_info *mtd = container_of(sys_dev, struct mtd_info, dev);
590         struct r852_device *dev = r852_get_dev(mtd);
591         char *data = dev->sm ? "smartmedia" : "xd";
592
593         strcpy(buf, data);
594         return strlen(data);
595 }
596 static DEVICE_ATTR_RO(media_type);
597
598
599 /* Detect properties of card in slot */
600 static void r852_update_media_status(struct r852_device *dev)
601 {
602         uint8_t reg;
603         unsigned long flags;
604         int readonly;
605
606         spin_lock_irqsave(&dev->irqlock, flags);
607         if (!dev->card_detected) {
608                 message("card removed");
609                 spin_unlock_irqrestore(&dev->irqlock, flags);
610                 return ;
611         }
612
613         readonly  = r852_read_reg(dev, R852_CARD_STA) & R852_CARD_STA_RO;
614         reg = r852_read_reg(dev, R852_DMA_CAP);
615         dev->sm = (reg & (R852_DMA1 | R852_DMA2)) && (reg & R852_SMBIT);
616
617         message("detected %s %s card in slot",
618                 dev->sm ? "SmartMedia" : "xD",
619                 readonly ? "readonly" : "writeable");
620
621         dev->readonly = readonly;
622         spin_unlock_irqrestore(&dev->irqlock, flags);
623 }
624
625 /*
626  * Register the nand device
627  * Called when the card is detected
628  */
629 static int r852_register_nand_device(struct r852_device *dev)
630 {
631         struct mtd_info *mtd = nand_to_mtd(dev->chip);
632
633         WARN_ON(dev->card_registered);
634
635         mtd->dev.parent = &dev->pci_dev->dev;
636
637         if (dev->readonly)
638                 dev->chip->options |= NAND_ROM;
639
640         r852_engine_enable(dev);
641
642         if (sm_register_device(mtd, dev->sm))
643                 goto error1;
644
645         if (device_create_file(&mtd->dev, &dev_attr_media_type)) {
646                 message("can't create media type sysfs attribute");
647                 goto error3;
648         }
649
650         dev->card_registered = 1;
651         return 0;
652 error3:
653         WARN_ON(mtd_device_unregister(nand_to_mtd(dev->chip)));
654         nand_cleanup(dev->chip);
655 error1:
656         /* Force card redetect */
657         dev->card_detected = 0;
658         return -1;
659 }
660
661 /*
662  * Unregister the card
663  */
664
665 static void r852_unregister_nand_device(struct r852_device *dev)
666 {
667         struct mtd_info *mtd = nand_to_mtd(dev->chip);
668
669         if (!dev->card_registered)
670                 return;
671
672         device_remove_file(&mtd->dev, &dev_attr_media_type);
673         WARN_ON(mtd_device_unregister(mtd));
674         nand_cleanup(dev->chip);
675         r852_engine_disable(dev);
676         dev->card_registered = 0;
677 }
678
679 /* Card state updater */
680 static void r852_card_detect_work(struct work_struct *work)
681 {
682         struct r852_device *dev =
683                 container_of(work, struct r852_device, card_detect_work.work);
684
685         r852_card_update_present(dev);
686         r852_update_card_detect(dev);
687         dev->card_unstable = 0;
688
689         /* False alarm */
690         if (dev->card_detected == dev->card_registered)
691                 goto exit;
692
693         /* Read media properties */
694         r852_update_media_status(dev);
695
696         /* Register the card */
697         if (dev->card_detected)
698                 r852_register_nand_device(dev);
699         else
700                 r852_unregister_nand_device(dev);
701 exit:
702         r852_update_card_detect(dev);
703 }
704
705 /* Ack + disable IRQ generation */
706 static void r852_disable_irqs(struct r852_device *dev)
707 {
708         uint8_t reg;
709         reg = r852_read_reg(dev, R852_CARD_IRQ_ENABLE);
710         r852_write_reg(dev, R852_CARD_IRQ_ENABLE, reg & ~R852_CARD_IRQ_MASK);
711
712         reg = r852_read_reg_dword(dev, R852_DMA_IRQ_ENABLE);
713         r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE,
714                                         reg & ~R852_DMA_IRQ_MASK);
715
716         r852_write_reg(dev, R852_CARD_IRQ_STA, R852_CARD_IRQ_MASK);
717         r852_write_reg_dword(dev, R852_DMA_IRQ_STA, R852_DMA_IRQ_MASK);
718 }
719
720 /* Interrupt handler */
721 static irqreturn_t r852_irq(int irq, void *data)
722 {
723         struct r852_device *dev = (struct r852_device *)data;
724
725         uint8_t card_status, dma_status;
726         irqreturn_t ret = IRQ_NONE;
727
728         spin_lock(&dev->irqlock);
729
730         /* handle card detection interrupts first */
731         card_status = r852_read_reg(dev, R852_CARD_IRQ_STA);
732         r852_write_reg(dev, R852_CARD_IRQ_STA, card_status);
733
734         if (card_status & (R852_CARD_IRQ_INSERT|R852_CARD_IRQ_REMOVE)) {
735
736                 ret = IRQ_HANDLED;
737                 dev->card_detected = !!(card_status & R852_CARD_IRQ_INSERT);
738
739                 /* we shouldn't receive any interrupts if we wait for card
740                         to settle */
741                 WARN_ON(dev->card_unstable);
742
743                 /* disable irqs while card is unstable */
744                 /* this will timeout DMA if active, but better that garbage */
745                 r852_disable_irqs(dev);
746
747                 if (dev->card_unstable)
748                         goto out;
749
750                 /* let, card state to settle a bit, and then do the work */
751                 dev->card_unstable = 1;
752                 queue_delayed_work(dev->card_workqueue,
753                         &dev->card_detect_work, msecs_to_jiffies(100));
754                 goto out;
755         }
756
757
758         /* Handle dma interrupts */
759         dma_status = r852_read_reg_dword(dev, R852_DMA_IRQ_STA);
760         r852_write_reg_dword(dev, R852_DMA_IRQ_STA, dma_status);
761
762         if (dma_status & R852_DMA_IRQ_MASK) {
763
764                 ret = IRQ_HANDLED;
765
766                 if (dma_status & R852_DMA_IRQ_ERROR) {
767                         dbg("received dma error IRQ");
768                         r852_dma_done(dev, -EIO);
769                         complete(&dev->dma_done);
770                         goto out;
771                 }
772
773                 /* received DMA interrupt out of nowhere? */
774                 WARN_ON_ONCE(dev->dma_stage == 0);
775
776                 if (dev->dma_stage == 0)
777                         goto out;
778
779                 /* done device access */
780                 if (dev->dma_state == DMA_INTERNAL &&
781                                 (dma_status & R852_DMA_IRQ_INTERNAL)) {
782
783                         dev->dma_state = DMA_MEMORY;
784                         dev->dma_stage++;
785                 }
786
787                 /* done memory DMA */
788                 if (dev->dma_state == DMA_MEMORY &&
789                                 (dma_status & R852_DMA_IRQ_MEMORY)) {
790                         dev->dma_state = DMA_INTERNAL;
791                         dev->dma_stage++;
792                 }
793
794                 /* Enable 2nd half of dma dance */
795                 if (dev->dma_stage == 2)
796                         r852_dma_enable(dev);
797
798                 /* Operation done */
799                 if (dev->dma_stage == 3) {
800                         r852_dma_done(dev, 0);
801                         complete(&dev->dma_done);
802                 }
803                 goto out;
804         }
805
806         /* Handle unknown interrupts */
807         if (dma_status)
808                 dbg("bad dma IRQ status = %x", dma_status);
809
810         if (card_status & ~R852_CARD_STA_CD)
811                 dbg("strange card status = %x", card_status);
812
813 out:
814         spin_unlock(&dev->irqlock);
815         return ret;
816 }
817
818 static int r852_attach_chip(struct nand_chip *chip)
819 {
820         if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST)
821                 return 0;
822
823         chip->ecc.placement = NAND_ECC_PLACEMENT_INTERLEAVED;
824         chip->ecc.size = R852_DMA_LEN;
825         chip->ecc.bytes = SM_OOB_SIZE;
826         chip->ecc.strength = 2;
827         chip->ecc.hwctl = r852_ecc_hwctl;
828         chip->ecc.calculate = r852_ecc_calculate;
829         chip->ecc.correct = r852_ecc_correct;
830
831         /* TODO: hack */
832         chip->ecc.read_oob = r852_read_oob;
833
834         return 0;
835 }
836
837 static const struct nand_controller_ops r852_ops = {
838         .attach_chip = r852_attach_chip,
839 };
840
841 static int  r852_probe(struct pci_dev *pci_dev, const struct pci_device_id *id)
842 {
843         int error;
844         struct nand_chip *chip;
845         struct r852_device *dev;
846
847         /* pci initialization */
848         error = pci_enable_device(pci_dev);
849
850         if (error)
851                 goto error1;
852
853         pci_set_master(pci_dev);
854
855         error = dma_set_mask(&pci_dev->dev, DMA_BIT_MASK(32));
856         if (error)
857                 goto error2;
858
859         error = pci_request_regions(pci_dev, DRV_NAME);
860
861         if (error)
862                 goto error3;
863
864         error = -ENOMEM;
865
866         /* init nand chip, but register it only on card insert */
867         chip = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
868
869         if (!chip)
870                 goto error4;
871
872         /* commands */
873         chip->legacy.cmd_ctrl = r852_cmdctl;
874         chip->legacy.waitfunc = r852_wait;
875         chip->legacy.dev_ready = r852_ready;
876
877         /* I/O */
878         chip->legacy.read_byte = r852_read_byte;
879         chip->legacy.read_buf = r852_read_buf;
880         chip->legacy.write_buf = r852_write_buf;
881
882         /* init our device structure */
883         dev = kzalloc(sizeof(struct r852_device), GFP_KERNEL);
884
885         if (!dev)
886                 goto error5;
887
888         nand_set_controller_data(chip, dev);
889         dev->chip = chip;
890         dev->pci_dev = pci_dev;
891         pci_set_drvdata(pci_dev, dev);
892
893         nand_controller_init(&dev->controller);
894         dev->controller.ops = &r852_ops;
895         chip->controller = &dev->controller;
896
897         dev->bounce_buffer = dma_alloc_coherent(&pci_dev->dev, R852_DMA_LEN,
898                 &dev->phys_bounce_buffer, GFP_KERNEL);
899
900         if (!dev->bounce_buffer)
901                 goto error6;
902
903
904         error = -ENODEV;
905         dev->mmio = pci_ioremap_bar(pci_dev, 0);
906
907         if (!dev->mmio)
908                 goto error7;
909
910         error = -ENOMEM;
911         dev->tmp_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL);
912
913         if (!dev->tmp_buffer)
914                 goto error8;
915
916         init_completion(&dev->dma_done);
917
918         dev->card_workqueue = create_freezable_workqueue(DRV_NAME);
919
920         if (!dev->card_workqueue)
921                 goto error9;
922
923         INIT_DELAYED_WORK(&dev->card_detect_work, r852_card_detect_work);
924
925         /* shutdown everything - precation */
926         r852_engine_disable(dev);
927         r852_disable_irqs(dev);
928
929         r852_dma_test(dev);
930
931         dev->irq = pci_dev->irq;
932         spin_lock_init(&dev->irqlock);
933
934         dev->card_detected = 0;
935         r852_card_update_present(dev);
936
937         /*register irq handler*/
938         error = -ENODEV;
939         if (request_irq(pci_dev->irq, &r852_irq, IRQF_SHARED,
940                           DRV_NAME, dev))
941                 goto error10;
942
943         /* kick initial present test */
944         queue_delayed_work(dev->card_workqueue,
945                 &dev->card_detect_work, 0);
946
947
948         pr_notice("driver loaded successfully\n");
949         return 0;
950
951 error10:
952         destroy_workqueue(dev->card_workqueue);
953 error9:
954         kfree(dev->tmp_buffer);
955 error8:
956         pci_iounmap(pci_dev, dev->mmio);
957 error7:
958         dma_free_coherent(&pci_dev->dev, R852_DMA_LEN, dev->bounce_buffer,
959                           dev->phys_bounce_buffer);
960 error6:
961         kfree(dev);
962 error5:
963         kfree(chip);
964 error4:
965         pci_release_regions(pci_dev);
966 error3:
967 error2:
968         pci_disable_device(pci_dev);
969 error1:
970         return error;
971 }
972
973 static void r852_remove(struct pci_dev *pci_dev)
974 {
975         struct r852_device *dev = pci_get_drvdata(pci_dev);
976
977         /* Stop detect workqueue -
978                 we are going to unregister the device anyway*/
979         cancel_delayed_work_sync(&dev->card_detect_work);
980         destroy_workqueue(dev->card_workqueue);
981
982         /* Unregister the device, this might make more IO */
983         r852_unregister_nand_device(dev);
984
985         /* Stop interrupts */
986         r852_disable_irqs(dev);
987         free_irq(dev->irq, dev);
988
989         /* Cleanup */
990         kfree(dev->tmp_buffer);
991         pci_iounmap(pci_dev, dev->mmio);
992         dma_free_coherent(&pci_dev->dev, R852_DMA_LEN, dev->bounce_buffer,
993                           dev->phys_bounce_buffer);
994
995         kfree(dev->chip);
996         kfree(dev);
997
998         /* Shutdown the PCI device */
999         pci_release_regions(pci_dev);
1000         pci_disable_device(pci_dev);
1001 }
1002
1003 static void r852_shutdown(struct pci_dev *pci_dev)
1004 {
1005         struct r852_device *dev = pci_get_drvdata(pci_dev);
1006
1007         cancel_delayed_work_sync(&dev->card_detect_work);
1008         r852_disable_irqs(dev);
1009         synchronize_irq(dev->irq);
1010         pci_disable_device(pci_dev);
1011 }
1012
1013 #ifdef CONFIG_PM_SLEEP
1014 static int r852_suspend(struct device *device)
1015 {
1016         struct r852_device *dev = dev_get_drvdata(device);
1017
1018         if (dev->ctlreg & R852_CTL_CARDENABLE)
1019                 return -EBUSY;
1020
1021         /* First make sure the detect work is gone */
1022         cancel_delayed_work_sync(&dev->card_detect_work);
1023
1024         /* Turn off the interrupts and stop the device */
1025         r852_disable_irqs(dev);
1026         r852_engine_disable(dev);
1027
1028         /* If card was pulled off just during the suspend, which is very
1029                 unlikely, we will remove it on resume, it too late now
1030                 anyway... */
1031         dev->card_unstable = 0;
1032         return 0;
1033 }
1034
1035 static int r852_resume(struct device *device)
1036 {
1037         struct r852_device *dev = dev_get_drvdata(device);
1038
1039         r852_disable_irqs(dev);
1040         r852_card_update_present(dev);
1041         r852_engine_disable(dev);
1042
1043
1044         /* If card status changed, just do the work */
1045         if (dev->card_detected != dev->card_registered) {
1046                 dbg("card was %s during low power state",
1047                         dev->card_detected ? "added" : "removed");
1048
1049                 queue_delayed_work(dev->card_workqueue,
1050                 &dev->card_detect_work, msecs_to_jiffies(1000));
1051                 return 0;
1052         }
1053
1054         /* Otherwise, initialize the card */
1055         if (dev->card_registered) {
1056                 r852_engine_enable(dev);
1057                 nand_select_target(dev->chip, 0);
1058                 nand_reset_op(dev->chip);
1059                 nand_deselect_target(dev->chip);
1060         }
1061
1062         /* Program card detection IRQ */
1063         r852_update_card_detect(dev);
1064         return 0;
1065 }
1066 #endif
1067
1068 static const struct pci_device_id r852_pci_id_tbl[] = {
1069
1070         { PCI_VDEVICE(RICOH, 0x0852), },
1071         { },
1072 };
1073
1074 MODULE_DEVICE_TABLE(pci, r852_pci_id_tbl);
1075
1076 static SIMPLE_DEV_PM_OPS(r852_pm_ops, r852_suspend, r852_resume);
1077
1078 static struct pci_driver r852_pci_driver = {
1079         .name           = DRV_NAME,
1080         .id_table       = r852_pci_id_tbl,
1081         .probe          = r852_probe,
1082         .remove         = r852_remove,
1083         .shutdown       = r852_shutdown,
1084         .driver.pm      = &r852_pm_ops,
1085 };
1086
1087 module_pci_driver(r852_pci_driver);
1088
1089 MODULE_LICENSE("GPL");
1090 MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
1091 MODULE_DESCRIPTION("Ricoh 85xx xD/smartmedia card reader driver");