xref: /openbmc/linux/drivers/mmc/host/cb710-mmc.c (revision 3381df09)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  cb710/mmc.c
4  *
5  *  Copyright by Michał Mirosław, 2008-2009
6  */
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/pci.h>
10 #include <linux/delay.h>
11 #include "cb710-mmc.h"
12 
13 static const u8 cb710_clock_divider_log2[8] = {
14 /*	1, 2, 4, 8, 16, 32, 128, 512 */
15 	0, 1, 2, 3,  4,  5,   7,   9
16 };
17 #define CB710_MAX_DIVIDER_IDX	\
18 	(ARRAY_SIZE(cb710_clock_divider_log2) - 1)
19 
20 static const u8 cb710_src_freq_mhz[16] = {
21 	33, 10, 20, 25, 30, 35, 40, 45,
22 	50, 55, 60, 65, 70, 75, 80, 85
23 };
24 
25 static void cb710_mmc_select_clock_divider(struct mmc_host *mmc, int hz)
26 {
27 	struct cb710_slot *slot = cb710_mmc_to_slot(mmc);
28 	struct pci_dev *pdev = cb710_slot_to_chip(slot)->pdev;
29 	u32 src_freq_idx;
30 	u32 divider_idx;
31 	int src_hz;
32 
33 	/* on CB710 in HP nx9500:
34 	 *   src_freq_idx == 0
35 	 *   indexes 1-7 work as written in the table
36 	 *   indexes 0,8-15 give no clock output
37 	 */
38 	pci_read_config_dword(pdev, 0x48, &src_freq_idx);
39 	src_freq_idx = (src_freq_idx >> 16) & 0xF;
40 	src_hz = cb710_src_freq_mhz[src_freq_idx] * 1000000;
41 
42 	for (divider_idx = 0; divider_idx < CB710_MAX_DIVIDER_IDX; ++divider_idx) {
43 		if (hz >= src_hz >> cb710_clock_divider_log2[divider_idx])
44 			break;
45 	}
46 
47 	if (src_freq_idx)
48 		divider_idx |= 0x8;
49 	else if (divider_idx == 0)
50 		divider_idx = 1;
51 
52 	cb710_pci_update_config_reg(pdev, 0x40, ~0xF0000000, divider_idx << 28);
53 
54 	dev_dbg(cb710_slot_dev(slot),
55 		"clock set to %d Hz, wanted %d Hz; src_freq_idx = %d, divider_idx = %d|%d\n",
56 		src_hz >> cb710_clock_divider_log2[divider_idx & 7],
57 		hz, src_freq_idx, divider_idx & 7, divider_idx & 8);
58 }
59 
60 static void __cb710_mmc_enable_irq(struct cb710_slot *slot,
61 	unsigned short enable, unsigned short mask)
62 {
63 	/* clear global IE
64 	 * - it gets set later if any interrupt sources are enabled */
65 	mask |= CB710_MMC_IE_IRQ_ENABLE;
66 
67 	/* look like interrupt is fired whenever
68 	 * WORD[0x0C] & WORD[0x10] != 0;
69 	 * -> bit 15 port 0x0C seems to be global interrupt enable
70 	 */
71 
72 	enable = (cb710_read_port_16(slot, CB710_MMC_IRQ_ENABLE_PORT)
73 		& ~mask) | enable;
74 
75 	if (enable)
76 		enable |= CB710_MMC_IE_IRQ_ENABLE;
77 
78 	cb710_write_port_16(slot, CB710_MMC_IRQ_ENABLE_PORT, enable);
79 }
80 
81 static void cb710_mmc_enable_irq(struct cb710_slot *slot,
82 	unsigned short enable, unsigned short mask)
83 {
84 	struct cb710_mmc_reader *reader = mmc_priv(cb710_slot_to_mmc(slot));
85 	unsigned long flags;
86 
87 	spin_lock_irqsave(&reader->irq_lock, flags);
88 	/* this is the only thing irq_lock protects */
89 	__cb710_mmc_enable_irq(slot, enable, mask);
90 	spin_unlock_irqrestore(&reader->irq_lock, flags);
91 }
92 
93 static void cb710_mmc_reset_events(struct cb710_slot *slot)
94 {
95 	cb710_write_port_8(slot, CB710_MMC_STATUS0_PORT, 0xFF);
96 	cb710_write_port_8(slot, CB710_MMC_STATUS1_PORT, 0xFF);
97 	cb710_write_port_8(slot, CB710_MMC_STATUS2_PORT, 0xFF);
98 }
99 
100 static void cb710_mmc_enable_4bit_data(struct cb710_slot *slot, int enable)
101 {
102 	if (enable)
103 		cb710_modify_port_8(slot, CB710_MMC_CONFIG1_PORT,
104 			CB710_MMC_C1_4BIT_DATA_BUS, 0);
105 	else
106 		cb710_modify_port_8(slot, CB710_MMC_CONFIG1_PORT,
107 			0, CB710_MMC_C1_4BIT_DATA_BUS);
108 }
109 
110 static int cb710_check_event(struct cb710_slot *slot, u8 what)
111 {
112 	u16 status;
113 
114 	status = cb710_read_port_16(slot, CB710_MMC_STATUS_PORT);
115 
116 	if (status & CB710_MMC_S0_FIFO_UNDERFLOW) {
117 		/* it is just a guess, so log it */
118 		dev_dbg(cb710_slot_dev(slot),
119 			"CHECK : ignoring bit 6 in status %04X\n", status);
120 		cb710_write_port_8(slot, CB710_MMC_STATUS0_PORT,
121 			CB710_MMC_S0_FIFO_UNDERFLOW);
122 		status &= ~CB710_MMC_S0_FIFO_UNDERFLOW;
123 	}
124 
125 	if (status & CB710_MMC_STATUS_ERROR_EVENTS) {
126 		dev_dbg(cb710_slot_dev(slot),
127 			"CHECK : returning EIO on status %04X\n", status);
128 		cb710_write_port_8(slot, CB710_MMC_STATUS0_PORT, status & 0xFF);
129 		cb710_write_port_8(slot, CB710_MMC_STATUS1_PORT,
130 			CB710_MMC_S1_RESET);
131 		return -EIO;
132 	}
133 
134 	/* 'what' is a bit in MMC_STATUS1 */
135 	if ((status >> 8) & what) {
136 		cb710_write_port_8(slot, CB710_MMC_STATUS1_PORT, what);
137 		return 1;
138 	}
139 
140 	return 0;
141 }
142 
143 static int cb710_wait_for_event(struct cb710_slot *slot, u8 what)
144 {
145 	int err = 0;
146 	unsigned limit = 2000000;	/* FIXME: real timeout */
147 
148 #ifdef CONFIG_CB710_DEBUG
149 	u32 e, x;
150 	e = cb710_read_port_32(slot, CB710_MMC_STATUS_PORT);
151 #endif
152 
153 	while (!(err = cb710_check_event(slot, what))) {
154 		if (!--limit) {
155 			cb710_dump_regs(cb710_slot_to_chip(slot),
156 				CB710_DUMP_REGS_MMC);
157 			err = -ETIMEDOUT;
158 			break;
159 		}
160 		udelay(1);
161 	}
162 
163 #ifdef CONFIG_CB710_DEBUG
164 	x = cb710_read_port_32(slot, CB710_MMC_STATUS_PORT);
165 
166 	limit = 2000000 - limit;
167 	if (limit > 100)
168 		dev_dbg(cb710_slot_dev(slot),
169 			"WAIT10: waited %d loops, what %d, entry val %08X, exit val %08X\n",
170 			limit, what, e, x);
171 #endif
172 	return err < 0 ? err : 0;
173 }
174 
175 
176 static int cb710_wait_while_busy(struct cb710_slot *slot, uint8_t mask)
177 {
178 	unsigned limit = 500000;	/* FIXME: real timeout */
179 	int err = 0;
180 
181 #ifdef CONFIG_CB710_DEBUG
182 	u32 e, x;
183 	e = cb710_read_port_32(slot, CB710_MMC_STATUS_PORT);
184 #endif
185 
186 	while (cb710_read_port_8(slot, CB710_MMC_STATUS2_PORT) & mask) {
187 		if (!--limit) {
188 			cb710_dump_regs(cb710_slot_to_chip(slot),
189 				CB710_DUMP_REGS_MMC);
190 			err = -ETIMEDOUT;
191 			break;
192 		}
193 		udelay(1);
194 	}
195 
196 #ifdef CONFIG_CB710_DEBUG
197 	x = cb710_read_port_32(slot, CB710_MMC_STATUS_PORT);
198 
199 	limit = 500000 - limit;
200 	if (limit > 100)
201 		dev_dbg(cb710_slot_dev(slot),
202 			"WAIT12: waited %d loops, mask %02X, entry val %08X, exit val %08X\n",
203 			limit, mask, e, x);
204 #endif
205 	return err;
206 }
207 
208 static void cb710_mmc_set_transfer_size(struct cb710_slot *slot,
209 	size_t count, size_t blocksize)
210 {
211 	cb710_wait_while_busy(slot, CB710_MMC_S2_BUSY_20);
212 	cb710_write_port_32(slot, CB710_MMC_TRANSFER_SIZE_PORT,
213 		((count - 1) << 16)|(blocksize - 1));
214 
215 	dev_vdbg(cb710_slot_dev(slot), "set up for %zu block%s of %zu bytes\n",
216 		count, count == 1 ? "" : "s", blocksize);
217 }
218 
219 static void cb710_mmc_fifo_hack(struct cb710_slot *slot)
220 {
221 	/* without this, received data is prepended with 8-bytes of zeroes */
222 	u32 r1, r2;
223 	int ok = 0;
224 
225 	r1 = cb710_read_port_32(slot, CB710_MMC_DATA_PORT);
226 	r2 = cb710_read_port_32(slot, CB710_MMC_DATA_PORT);
227 	if (cb710_read_port_8(slot, CB710_MMC_STATUS0_PORT)
228 	    & CB710_MMC_S0_FIFO_UNDERFLOW) {
229 		cb710_write_port_8(slot, CB710_MMC_STATUS0_PORT,
230 			CB710_MMC_S0_FIFO_UNDERFLOW);
231 		ok = 1;
232 	}
233 
234 	dev_dbg(cb710_slot_dev(slot),
235 		"FIFO-read-hack: expected STATUS0 bit was %s\n",
236 		ok ? "set." : "NOT SET!");
237 	dev_dbg(cb710_slot_dev(slot),
238 		"FIFO-read-hack: dwords ignored: %08X %08X - %s\n",
239 		r1, r2, (r1|r2) ? "BAD (NOT ZERO)!" : "ok");
240 }
241 
242 static int cb710_mmc_receive_pio(struct cb710_slot *slot,
243 	struct sg_mapping_iter *miter, size_t dw_count)
244 {
245 	if (!(cb710_read_port_8(slot, CB710_MMC_STATUS2_PORT) & CB710_MMC_S2_FIFO_READY)) {
246 		int err = cb710_wait_for_event(slot,
247 			CB710_MMC_S1_PIO_TRANSFER_DONE);
248 		if (err)
249 			return err;
250 	}
251 
252 	cb710_sg_dwiter_write_from_io(miter,
253 		slot->iobase + CB710_MMC_DATA_PORT, dw_count);
254 
255 	return 0;
256 }
257 
258 static bool cb710_is_transfer_size_supported(struct mmc_data *data)
259 {
260 	return !(data->blksz & 15 && (data->blocks != 1 || data->blksz != 8));
261 }
262 
263 static int cb710_mmc_receive(struct cb710_slot *slot, struct mmc_data *data)
264 {
265 	struct sg_mapping_iter miter;
266 	size_t len, blocks = data->blocks;
267 	int err = 0;
268 
269 	/* TODO: I don't know how/if the hardware handles non-16B-boundary blocks
270 	 * except single 8B block */
271 	if (unlikely(data->blksz & 15 && (data->blocks != 1 || data->blksz != 8)))
272 		return -EINVAL;
273 
274 	sg_miter_start(&miter, data->sg, data->sg_len, SG_MITER_TO_SG);
275 
276 	cb710_modify_port_8(slot, CB710_MMC_CONFIG2_PORT,
277 		15, CB710_MMC_C2_READ_PIO_SIZE_MASK);
278 
279 	cb710_mmc_fifo_hack(slot);
280 
281 	while (blocks-- > 0) {
282 		len = data->blksz;
283 
284 		while (len >= 16) {
285 			err = cb710_mmc_receive_pio(slot, &miter, 4);
286 			if (err)
287 				goto out;
288 			len -= 16;
289 		}
290 
291 		if (!len)
292 			continue;
293 
294 		cb710_modify_port_8(slot, CB710_MMC_CONFIG2_PORT,
295 			len - 1, CB710_MMC_C2_READ_PIO_SIZE_MASK);
296 
297 		len = (len >= 8) ? 4 : 2;
298 		err = cb710_mmc_receive_pio(slot, &miter, len);
299 		if (err)
300 			goto out;
301 	}
302 out:
303 	sg_miter_stop(&miter);
304 	return err;
305 }
306 
307 static int cb710_mmc_send(struct cb710_slot *slot, struct mmc_data *data)
308 {
309 	struct sg_mapping_iter miter;
310 	size_t len, blocks = data->blocks;
311 	int err = 0;
312 
313 	/* TODO: I don't know how/if the hardware handles multiple
314 	 * non-16B-boundary blocks */
315 	if (unlikely(data->blocks > 1 && data->blksz & 15))
316 		return -EINVAL;
317 
318 	sg_miter_start(&miter, data->sg, data->sg_len, SG_MITER_FROM_SG);
319 
320 	cb710_modify_port_8(slot, CB710_MMC_CONFIG2_PORT,
321 		0, CB710_MMC_C2_READ_PIO_SIZE_MASK);
322 
323 	while (blocks-- > 0) {
324 		len = (data->blksz + 15) >> 4;
325 		do {
326 			if (!(cb710_read_port_8(slot, CB710_MMC_STATUS2_PORT)
327 			    & CB710_MMC_S2_FIFO_EMPTY)) {
328 				err = cb710_wait_for_event(slot,
329 					CB710_MMC_S1_PIO_TRANSFER_DONE);
330 				if (err)
331 					goto out;
332 			}
333 			cb710_sg_dwiter_read_to_io(&miter,
334 				slot->iobase + CB710_MMC_DATA_PORT, 4);
335 		} while (--len);
336 	}
337 out:
338 	sg_miter_stop(&miter);
339 	return err;
340 }
341 
342 static u16 cb710_encode_cmd_flags(struct cb710_mmc_reader *reader,
343 	struct mmc_command *cmd)
344 {
345 	unsigned int flags = cmd->flags;
346 	u16 cb_flags = 0;
347 
348 	/* Windows driver returned 0 for commands for which no response
349 	 * is expected. It happened that there were only two such commands
350 	 * used: MMC_GO_IDLE_STATE and MMC_GO_INACTIVE_STATE so it might
351 	 * as well be a bug in that driver.
352 	 *
353 	 * Original driver set bit 14 for MMC/SD application
354 	 * commands. There's no difference 'on the wire' and
355 	 * it apparently works without it anyway.
356 	 */
357 
358 	switch (flags & MMC_CMD_MASK) {
359 	case MMC_CMD_AC:	cb_flags = CB710_MMC_CMD_AC;	break;
360 	case MMC_CMD_ADTC:	cb_flags = CB710_MMC_CMD_ADTC;	break;
361 	case MMC_CMD_BC:	cb_flags = CB710_MMC_CMD_BC;	break;
362 	case MMC_CMD_BCR:	cb_flags = CB710_MMC_CMD_BCR;	break;
363 	}
364 
365 	if (flags & MMC_RSP_BUSY)
366 		cb_flags |= CB710_MMC_RSP_BUSY;
367 
368 	cb_flags |= cmd->opcode << CB710_MMC_CMD_CODE_SHIFT;
369 
370 	if (cmd->data && (cmd->data->flags & MMC_DATA_READ))
371 		cb_flags |= CB710_MMC_DATA_READ;
372 
373 	if (flags & MMC_RSP_PRESENT) {
374 		/* Windows driver set 01 at bits 4,3 except for
375 		 * MMC_SET_BLOCKLEN where it set 10. Maybe the
376 		 * hardware can do something special about this
377 		 * command? The original driver looks buggy/incomplete
378 		 * anyway so we ignore this for now.
379 		 *
380 		 * I assume that 00 here means no response is expected.
381 		 */
382 		cb_flags |= CB710_MMC_RSP_PRESENT;
383 
384 		if (flags & MMC_RSP_136)
385 			cb_flags |= CB710_MMC_RSP_136;
386 		if (!(flags & MMC_RSP_CRC))
387 			cb_flags |= CB710_MMC_RSP_NO_CRC;
388 	}
389 
390 	return cb_flags;
391 }
392 
393 static void cb710_receive_response(struct cb710_slot *slot,
394 	struct mmc_command *cmd)
395 {
396 	unsigned rsp_opcode, wanted_opcode;
397 
398 	/* Looks like final byte with CRC is always stripped (same as SDHCI) */
399 	if (cmd->flags & MMC_RSP_136) {
400 		u32 resp[4];
401 
402 		resp[0] = cb710_read_port_32(slot, CB710_MMC_RESPONSE3_PORT);
403 		resp[1] = cb710_read_port_32(slot, CB710_MMC_RESPONSE2_PORT);
404 		resp[2] = cb710_read_port_32(slot, CB710_MMC_RESPONSE1_PORT);
405 		resp[3] = cb710_read_port_32(slot, CB710_MMC_RESPONSE0_PORT);
406 		rsp_opcode = resp[0] >> 24;
407 
408 		cmd->resp[0] = (resp[0] << 8)|(resp[1] >> 24);
409 		cmd->resp[1] = (resp[1] << 8)|(resp[2] >> 24);
410 		cmd->resp[2] = (resp[2] << 8)|(resp[3] >> 24);
411 		cmd->resp[3] = (resp[3] << 8);
412 	} else {
413 		rsp_opcode = cb710_read_port_32(slot, CB710_MMC_RESPONSE1_PORT) & 0x3F;
414 		cmd->resp[0] = cb710_read_port_32(slot, CB710_MMC_RESPONSE0_PORT);
415 	}
416 
417 	wanted_opcode = (cmd->flags & MMC_RSP_OPCODE) ? cmd->opcode : 0x3F;
418 	if (rsp_opcode != wanted_opcode)
419 		cmd->error = -EILSEQ;
420 }
421 
422 static int cb710_mmc_transfer_data(struct cb710_slot *slot,
423 	struct mmc_data *data)
424 {
425 	int error, to;
426 
427 	if (data->flags & MMC_DATA_READ)
428 		error = cb710_mmc_receive(slot, data);
429 	else
430 		error = cb710_mmc_send(slot, data);
431 
432 	to = cb710_wait_for_event(slot, CB710_MMC_S1_DATA_TRANSFER_DONE);
433 	if (!error)
434 		error = to;
435 
436 	if (!error)
437 		data->bytes_xfered = data->blksz * data->blocks;
438 	return error;
439 }
440 
441 static int cb710_mmc_command(struct mmc_host *mmc, struct mmc_command *cmd)
442 {
443 	struct cb710_slot *slot = cb710_mmc_to_slot(mmc);
444 	struct cb710_mmc_reader *reader = mmc_priv(mmc);
445 	struct mmc_data *data = cmd->data;
446 
447 	u16 cb_cmd = cb710_encode_cmd_flags(reader, cmd);
448 	dev_dbg(cb710_slot_dev(slot), "cmd request: 0x%04X\n", cb_cmd);
449 
450 	if (data) {
451 		if (!cb710_is_transfer_size_supported(data)) {
452 			data->error = -EINVAL;
453 			return -1;
454 		}
455 		cb710_mmc_set_transfer_size(slot, data->blocks, data->blksz);
456 	}
457 
458 	cb710_wait_while_busy(slot, CB710_MMC_S2_BUSY_20|CB710_MMC_S2_BUSY_10);
459 	cb710_write_port_16(slot, CB710_MMC_CMD_TYPE_PORT, cb_cmd);
460 	cb710_wait_while_busy(slot, CB710_MMC_S2_BUSY_20);
461 	cb710_write_port_32(slot, CB710_MMC_CMD_PARAM_PORT, cmd->arg);
462 	cb710_mmc_reset_events(slot);
463 	cb710_wait_while_busy(slot, CB710_MMC_S2_BUSY_20);
464 	cb710_modify_port_8(slot, CB710_MMC_CONFIG0_PORT, 0x01, 0);
465 
466 	cmd->error = cb710_wait_for_event(slot, CB710_MMC_S1_COMMAND_SENT);
467 	if (cmd->error)
468 		return -1;
469 
470 	if (cmd->flags & MMC_RSP_PRESENT) {
471 		cb710_receive_response(slot, cmd);
472 		if (cmd->error)
473 			return -1;
474 	}
475 
476 	if (data)
477 		data->error = cb710_mmc_transfer_data(slot, data);
478 	return 0;
479 }
480 
481 static void cb710_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
482 {
483 	struct cb710_slot *slot = cb710_mmc_to_slot(mmc);
484 	struct cb710_mmc_reader *reader = mmc_priv(mmc);
485 
486 	WARN_ON(reader->mrq != NULL);
487 
488 	reader->mrq = mrq;
489 	cb710_mmc_enable_irq(slot, CB710_MMC_IE_TEST_MASK, 0);
490 
491 	if (!cb710_mmc_command(mmc, mrq->cmd) && mrq->stop)
492 		cb710_mmc_command(mmc, mrq->stop);
493 
494 	tasklet_schedule(&reader->finish_req_tasklet);
495 }
496 
497 static int cb710_mmc_powerup(struct cb710_slot *slot)
498 {
499 #ifdef CONFIG_CB710_DEBUG
500 	struct cb710_chip *chip = cb710_slot_to_chip(slot);
501 #endif
502 	int err;
503 
504 	/* a lot of magic for now */
505 	dev_dbg(cb710_slot_dev(slot), "bus powerup\n");
506 	cb710_dump_regs(chip, CB710_DUMP_REGS_MMC);
507 	err = cb710_wait_while_busy(slot, CB710_MMC_S2_BUSY_20);
508 	if (unlikely(err))
509 		return err;
510 	cb710_modify_port_8(slot, CB710_MMC_CONFIG1_PORT, 0x80, 0);
511 	cb710_modify_port_8(slot, CB710_MMC_CONFIG3_PORT, 0x80, 0);
512 	cb710_dump_regs(chip, CB710_DUMP_REGS_MMC);
513 	mdelay(1);
514 	dev_dbg(cb710_slot_dev(slot), "after delay 1\n");
515 	cb710_dump_regs(chip, CB710_DUMP_REGS_MMC);
516 	err = cb710_wait_while_busy(slot, CB710_MMC_S2_BUSY_20);
517 	if (unlikely(err))
518 		return err;
519 	cb710_modify_port_8(slot, CB710_MMC_CONFIG1_PORT, 0x09, 0);
520 	cb710_dump_regs(chip, CB710_DUMP_REGS_MMC);
521 	mdelay(1);
522 	dev_dbg(cb710_slot_dev(slot), "after delay 2\n");
523 	cb710_dump_regs(chip, CB710_DUMP_REGS_MMC);
524 	err = cb710_wait_while_busy(slot, CB710_MMC_S2_BUSY_20);
525 	if (unlikely(err))
526 		return err;
527 	cb710_modify_port_8(slot, CB710_MMC_CONFIG1_PORT, 0, 0x08);
528 	cb710_dump_regs(chip, CB710_DUMP_REGS_MMC);
529 	mdelay(2);
530 	dev_dbg(cb710_slot_dev(slot), "after delay 3\n");
531 	cb710_dump_regs(chip, CB710_DUMP_REGS_MMC);
532 	cb710_modify_port_8(slot, CB710_MMC_CONFIG0_PORT, 0x06, 0);
533 	cb710_modify_port_8(slot, CB710_MMC_CONFIG1_PORT, 0x70, 0);
534 	cb710_modify_port_8(slot, CB710_MMC_CONFIG2_PORT, 0x80, 0);
535 	cb710_modify_port_8(slot, CB710_MMC_CONFIG3_PORT, 0x03, 0);
536 	cb710_dump_regs(chip, CB710_DUMP_REGS_MMC);
537 	err = cb710_wait_while_busy(slot, CB710_MMC_S2_BUSY_20);
538 	if (unlikely(err))
539 		return err;
540 	/* This port behaves weird: quick byte reads of 0x08,0x09 return
541 	 * 0xFF,0x00 after writing 0xFFFF to 0x08; it works correctly when
542 	 * read/written from userspace...  What am I missing here?
543 	 * (it doesn't depend on write-to-read delay) */
544 	cb710_write_port_16(slot, CB710_MMC_CONFIGB_PORT, 0xFFFF);
545 	cb710_modify_port_8(slot, CB710_MMC_CONFIG0_PORT, 0x06, 0);
546 	cb710_dump_regs(chip, CB710_DUMP_REGS_MMC);
547 	dev_dbg(cb710_slot_dev(slot), "bus powerup finished\n");
548 
549 	return cb710_check_event(slot, 0);
550 }
551 
552 static void cb710_mmc_powerdown(struct cb710_slot *slot)
553 {
554 	cb710_modify_port_8(slot, CB710_MMC_CONFIG1_PORT, 0, 0x81);
555 	cb710_modify_port_8(slot, CB710_MMC_CONFIG3_PORT, 0, 0x80);
556 }
557 
558 static void cb710_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
559 {
560 	struct cb710_slot *slot = cb710_mmc_to_slot(mmc);
561 	struct cb710_mmc_reader *reader = mmc_priv(mmc);
562 	int err;
563 
564 	cb710_mmc_select_clock_divider(mmc, ios->clock);
565 
566 	if (ios->power_mode != reader->last_power_mode) {
567 		switch (ios->power_mode) {
568 		case MMC_POWER_ON:
569 			err = cb710_mmc_powerup(slot);
570 			if (err) {
571 				dev_warn(cb710_slot_dev(slot),
572 					"powerup failed (%d)- retrying\n", err);
573 				cb710_mmc_powerdown(slot);
574 				udelay(1);
575 				err = cb710_mmc_powerup(slot);
576 				if (err)
577 					dev_warn(cb710_slot_dev(slot),
578 						"powerup retry failed (%d) - expect errors\n",
579 					err);
580 			}
581 			reader->last_power_mode = MMC_POWER_ON;
582 			break;
583 		case MMC_POWER_OFF:
584 			cb710_mmc_powerdown(slot);
585 			reader->last_power_mode = MMC_POWER_OFF;
586 			break;
587 		case MMC_POWER_UP:
588 		default:
589 			/* ignore */
590 			break;
591 		}
592 	}
593 
594 	cb710_mmc_enable_4bit_data(slot, ios->bus_width != MMC_BUS_WIDTH_1);
595 
596 	cb710_mmc_enable_irq(slot, CB710_MMC_IE_TEST_MASK, 0);
597 }
598 
599 static int cb710_mmc_get_ro(struct mmc_host *mmc)
600 {
601 	struct cb710_slot *slot = cb710_mmc_to_slot(mmc);
602 
603 	return cb710_read_port_8(slot, CB710_MMC_STATUS3_PORT)
604 		& CB710_MMC_S3_WRITE_PROTECTED;
605 }
606 
607 static int cb710_mmc_get_cd(struct mmc_host *mmc)
608 {
609 	struct cb710_slot *slot = cb710_mmc_to_slot(mmc);
610 
611 	return cb710_read_port_8(slot, CB710_MMC_STATUS3_PORT)
612 		& CB710_MMC_S3_CARD_DETECTED;
613 }
614 
615 static int cb710_mmc_irq_handler(struct cb710_slot *slot)
616 {
617 	struct mmc_host *mmc = cb710_slot_to_mmc(slot);
618 	struct cb710_mmc_reader *reader = mmc_priv(mmc);
619 	u32 status, config1, config2, irqen;
620 
621 	status = cb710_read_port_32(slot, CB710_MMC_STATUS_PORT);
622 	irqen = cb710_read_port_32(slot, CB710_MMC_IRQ_ENABLE_PORT);
623 	config2 = cb710_read_port_32(slot, CB710_MMC_CONFIGB_PORT);
624 	config1 = cb710_read_port_32(slot, CB710_MMC_CONFIG_PORT);
625 
626 	dev_dbg(cb710_slot_dev(slot), "interrupt; status: %08X, "
627 		"ie: %08X, c2: %08X, c1: %08X\n",
628 		status, irqen, config2, config1);
629 
630 	if (status & (CB710_MMC_S1_CARD_CHANGED << 8)) {
631 		/* ack the event */
632 		cb710_write_port_8(slot, CB710_MMC_STATUS1_PORT,
633 			CB710_MMC_S1_CARD_CHANGED);
634 		if ((irqen & CB710_MMC_IE_CISTATUS_MASK)
635 		    == CB710_MMC_IE_CISTATUS_MASK)
636 			mmc_detect_change(mmc, HZ/5);
637 	} else {
638 		dev_dbg(cb710_slot_dev(slot), "unknown interrupt (test)\n");
639 		spin_lock(&reader->irq_lock);
640 		__cb710_mmc_enable_irq(slot, 0, CB710_MMC_IE_TEST_MASK);
641 		spin_unlock(&reader->irq_lock);
642 	}
643 
644 	return 1;
645 }
646 
647 static void cb710_mmc_finish_request_tasklet(unsigned long data)
648 {
649 	struct mmc_host *mmc = (void *)data;
650 	struct cb710_mmc_reader *reader = mmc_priv(mmc);
651 	struct mmc_request *mrq = reader->mrq;
652 
653 	reader->mrq = NULL;
654 	mmc_request_done(mmc, mrq);
655 }
656 
657 static const struct mmc_host_ops cb710_mmc_host = {
658 	.request = cb710_mmc_request,
659 	.set_ios = cb710_mmc_set_ios,
660 	.get_ro = cb710_mmc_get_ro,
661 	.get_cd = cb710_mmc_get_cd,
662 };
663 
664 #ifdef CONFIG_PM
665 
666 static int cb710_mmc_suspend(struct platform_device *pdev, pm_message_t state)
667 {
668 	struct cb710_slot *slot = cb710_pdev_to_slot(pdev);
669 
670 	cb710_mmc_enable_irq(slot, 0, ~0);
671 	return 0;
672 }
673 
674 static int cb710_mmc_resume(struct platform_device *pdev)
675 {
676 	struct cb710_slot *slot = cb710_pdev_to_slot(pdev);
677 
678 	cb710_mmc_enable_irq(slot, 0, ~0);
679 	return 0;
680 }
681 
682 #endif /* CONFIG_PM */
683 
684 static int cb710_mmc_init(struct platform_device *pdev)
685 {
686 	struct cb710_slot *slot = cb710_pdev_to_slot(pdev);
687 	struct cb710_chip *chip = cb710_slot_to_chip(slot);
688 	struct mmc_host *mmc;
689 	struct cb710_mmc_reader *reader;
690 	int err;
691 	u32 val;
692 
693 	mmc = mmc_alloc_host(sizeof(*reader), cb710_slot_dev(slot));
694 	if (!mmc)
695 		return -ENOMEM;
696 
697 	platform_set_drvdata(pdev, mmc);
698 
699 	/* harmless (maybe) magic */
700 	pci_read_config_dword(chip->pdev, 0x48, &val);
701 	val = cb710_src_freq_mhz[(val >> 16) & 0xF];
702 	dev_dbg(cb710_slot_dev(slot), "source frequency: %dMHz\n", val);
703 	val *= 1000000;
704 
705 	mmc->ops = &cb710_mmc_host;
706 	mmc->f_max = val;
707 	mmc->f_min = val >> cb710_clock_divider_log2[CB710_MAX_DIVIDER_IDX];
708 	mmc->ocr_avail = MMC_VDD_32_33|MMC_VDD_33_34;
709 	mmc->caps = MMC_CAP_4_BIT_DATA;
710 
711 	reader = mmc_priv(mmc);
712 
713 	tasklet_init(&reader->finish_req_tasklet,
714 		cb710_mmc_finish_request_tasklet, (unsigned long)mmc);
715 	spin_lock_init(&reader->irq_lock);
716 	cb710_dump_regs(chip, CB710_DUMP_REGS_MMC);
717 
718 	cb710_mmc_enable_irq(slot, 0, ~0);
719 	cb710_set_irq_handler(slot, cb710_mmc_irq_handler);
720 
721 	err = mmc_add_host(mmc);
722 	if (unlikely(err))
723 		goto err_free_mmc;
724 
725 	dev_dbg(cb710_slot_dev(slot), "mmc_hostname is %s\n",
726 		mmc_hostname(mmc));
727 
728 	cb710_mmc_enable_irq(slot, CB710_MMC_IE_CARD_INSERTION_STATUS, 0);
729 
730 	return 0;
731 
732 err_free_mmc:
733 	dev_dbg(cb710_slot_dev(slot), "mmc_add_host() failed: %d\n", err);
734 
735 	cb710_set_irq_handler(slot, NULL);
736 	mmc_free_host(mmc);
737 	return err;
738 }
739 
740 static int cb710_mmc_exit(struct platform_device *pdev)
741 {
742 	struct cb710_slot *slot = cb710_pdev_to_slot(pdev);
743 	struct mmc_host *mmc = cb710_slot_to_mmc(slot);
744 	struct cb710_mmc_reader *reader = mmc_priv(mmc);
745 
746 	cb710_mmc_enable_irq(slot, 0, CB710_MMC_IE_CARD_INSERTION_STATUS);
747 
748 	mmc_remove_host(mmc);
749 
750 	/* IRQs should be disabled now, but let's stay on the safe side */
751 	cb710_mmc_enable_irq(slot, 0, ~0);
752 	cb710_set_irq_handler(slot, NULL);
753 
754 	/* clear config ports - just in case */
755 	cb710_write_port_32(slot, CB710_MMC_CONFIG_PORT, 0);
756 	cb710_write_port_16(slot, CB710_MMC_CONFIGB_PORT, 0);
757 
758 	tasklet_kill(&reader->finish_req_tasklet);
759 
760 	mmc_free_host(mmc);
761 	return 0;
762 }
763 
764 static struct platform_driver cb710_mmc_driver = {
765 	.driver.name = "cb710-mmc",
766 	.probe = cb710_mmc_init,
767 	.remove = cb710_mmc_exit,
768 #ifdef CONFIG_PM
769 	.suspend = cb710_mmc_suspend,
770 	.resume = cb710_mmc_resume,
771 #endif
772 };
773 
774 module_platform_driver(cb710_mmc_driver);
775 
776 MODULE_AUTHOR("Michał Mirosław <mirq-linux@rere.qmqm.pl>");
777 MODULE_DESCRIPTION("ENE CB710 memory card reader driver - MMC/SD part");
778 MODULE_LICENSE("GPL");
779 MODULE_ALIAS("platform:cb710-mmc");
780