aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/pinctrl/pinctrl-baytrail.c
blob: 9ca59a01874316585a190093b0265401e17975a3 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
/*
 * Pinctrl GPIO driver for Intel Baytrail
 * Copyright (c) 2012-2013, Intel Corporation.
 *
 * Author: Mathias Nyman <mathias.nyman@linux.intel.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <linux/acpi.h>
#include <linux/platform_device.h>
#include <linux/seq_file.h>
#include <linux/io.h>
#include <linux/pm_runtime.h>
#include <linux/pinctrl/pinctrl.h>

/* memory mapped register offsets */
#define BYT_CONF0_REG		0x000
#define BYT_CONF1_REG		0x004
#define BYT_VAL_REG		0x008
#define BYT_DFT_REG		0x00c
#define BYT_INT_STAT_REG	0x800

/* BYT_CONF0_REG register bits */
#define BYT_IODEN		BIT(31)
#define BYT_DIRECT_IRQ_EN	BIT(27)
#define BYT_TRIG_NEG		BIT(26)
#define BYT_TRIG_POS		BIT(25)
#define BYT_TRIG_LVL		BIT(24)
#define BYT_PULL_STR_SHIFT	9
#define BYT_PULL_STR_MASK	(3 << BYT_PULL_STR_SHIFT)
#define BYT_PULL_STR_2K		(0 << BYT_PULL_STR_SHIFT)
#define BYT_PULL_STR_10K	(1 << BYT_PULL_STR_SHIFT)
#define BYT_PULL_STR_20K	(2 << BYT_PULL_STR_SHIFT)
#define BYT_PULL_STR_40K	(3 << BYT_PULL_STR_SHIFT)
#define BYT_PULL_ASSIGN_SHIFT	7
#define BYT_PULL_ASSIGN_MASK	(3 << BYT_PULL_ASSIGN_SHIFT)
#define BYT_PULL_ASSIGN_UP	(1 << BYT_PULL_ASSIGN_SHIFT)
#define BYT_PULL_ASSIGN_DOWN	(2 << BYT_PULL_ASSIGN_SHIFT)
#define BYT_PIN_MUX		0x07

/* BYT_VAL_REG register bits */
#define BYT_INPUT_EN		BIT(2)  /* 0: input enabled (active low)*/
#define BYT_OUTPUT_EN		BIT(1)  /* 0: output enabled (active low)*/
#define BYT_LEVEL		BIT(0)

#define BYT_DIR_MASK		(BIT(1) | BIT(2))
#define BYT_TRIG_MASK		(BIT(26) | BIT(25) | BIT(24))

#define BYT_NGPIO_SCORE		102
#define BYT_NGPIO_NCORE		28
#define BYT_NGPIO_SUS		44

#define BYT_SCORE_ACPI_UID	"1"
#define BYT_NCORE_ACPI_UID	"2"
#define BYT_SUS_ACPI_UID	"3"

/*
 * Baytrail gpio controller consist of three separate sub-controllers called
 * SCORE, NCORE and SUS. The sub-controllers are identified by their acpi UID.
 *
 * GPIO numbering is _not_ ordered meaning that gpio # 0 in ACPI namespace does
 * _not_ correspond to the first gpio register at controller's gpio base.
 * There is no logic or pattern in mapping gpio numbers to registers (pads) so
 * each sub-controller needs to have its own mapping table
 */

/* score_pins[gpio_nr] = pad_nr */

static unsigned const score_pins[BYT_NGPIO_SCORE] = {
	85, 89, 93, 96, 99, 102, 98, 101, 34, 37,
	36, 38, 39, 35, 40, 84, 62, 61, 64, 59,
	54, 56, 60, 55, 63, 57, 51, 50, 53, 47,
	52, 49, 48, 43, 46, 41, 45, 42, 58, 44,
	95, 105, 70, 68, 67, 66, 69, 71, 65, 72,
	86, 90, 88, 92, 103, 77, 79, 83, 78, 81,
	80, 82, 13, 12, 15, 14, 17, 18, 19, 16,
	2, 1, 0, 4, 6, 7, 9, 8, 33, 32,
	31, 30, 29, 27, 25, 28, 26, 23, 21, 20,
	24, 22, 5, 3, 10, 11, 106, 87, 91, 104,
	97, 100,
};

static unsigned const ncore_pins[BYT_NGPIO_NCORE] = {
	19, 18, 17, 20, 21, 22, 24, 25, 23, 16,
	14, 15, 12, 26, 27, 1, 4, 8, 11, 0,
	3, 6, 10, 13, 2, 5, 9, 7,
};

static unsigned const sus_pins[BYT_NGPIO_SUS] = {
	29, 33, 30, 31, 32, 34, 36, 35, 38, 37,
	18, 7, 11, 20, 17, 1, 8, 10, 19, 12,
	0, 2, 23, 39, 28, 27, 22, 21, 24, 25,
	26, 51, 56, 54, 49, 55, 48, 57, 50, 58,
	52, 53, 59, 40,
};

static struct pinctrl_gpio_range byt_ranges[] = {
	{
		.name = BYT_SCORE_ACPI_UID, /* match with acpi _UID in probe */
		.npins = BYT_NGPIO_SCORE,
		.pins = score_pins,
	},
	{
		.name = BYT_NCORE_ACPI_UID,
		.npins = BYT_NGPIO_NCORE,
		.pins = ncore_pins,
	},
	{
		.name = BYT_SUS_ACPI_UID,
		.npins = BYT_NGPIO_SUS,
		.pins = sus_pins,
	},
	{
	},
};

struct byt_gpio {
	struct gpio_chip		chip;
	struct platform_device		*pdev;
	spinlock_t			lock;
	void __iomem			*reg_base;
	struct pinctrl_gpio_range	*range;
};

#define to_byt_gpio(c)	container_of(c, struct byt_gpio, chip)

static void __iomem *byt_gpio_reg(struct gpio_chip *chip, unsigned offset,
				 int reg)
{
	struct byt_gpio *vg = to_byt_gpio(chip);
	u32 reg_offset;

	if (reg == BYT_INT_STAT_REG)
		reg_offset = (offset / 32) * 4;
	else
		reg_offset = vg->range->pins[offset] * 16;

	return vg->reg_base + reg_offset + reg;
}

static bool is_special_pin(struct byt_gpio *vg, unsigned offset)
{
	/* SCORE pin 92-93 */
	if (!strcmp(vg->range->name, BYT_SCORE_ACPI_UID) &&
		offset >= 92 && offset <= 93)
		return true;

	/* SUS pin 11-21 */
	if (!strcmp(vg->range->name, BYT_SUS_ACPI_UID) &&
		offset >= 11 && offset <= 21)
		return true;

	return false;
}

static int byt_gpio_request(struct gpio_chip *chip, unsigned offset)
{
	struct byt_gpio *vg = to_byt_gpio(chip);
	void __iomem *reg = byt_gpio_reg(chip, offset, BYT_CONF0_REG);
	u32 value;
	bool special;

	/*
	 * In most cases, func pin mux 000 means GPIO function.
	 * But, some pins may have func pin mux 001 represents
	 * GPIO function. Only allow user to export pin with
	 * func pin mux preset as GPIO function by BIOS/FW.
	 */
	value = readl(reg) & BYT_PIN_MUX;
	special = is_special_pin(vg, offset);
	if ((special && value != 1) || (!special && value)) {
		dev_err(&vg->pdev->dev,
			"pin %u cannot be used as GPIO.\n", offset);
		return -EINVAL;
	}

	pm_runtime_get(&vg->pdev->dev);

	return 0;
}

static void byt_gpio_free(struct gpio_chip *chip, unsigned offset)
{
	struct byt_gpio *vg = to_byt_gpio(chip);
	void __iomem *reg = byt_gpio_reg(&vg->chip, offset, BYT_CONF0_REG);
	u32 value;

	/* clear interrupt triggering */
	value = readl(reg);
	value &= ~(BYT_TRIG_POS | BYT_TRIG_NEG | BYT_TRIG_LVL);
	writel(value, reg);

	pm_runtime_put(&vg->pdev->dev);
}

static int byt_irq_type(struct irq_data *d, unsigned type)
{
	struct byt_gpio *vg = to_byt_gpio(irq_data_get_irq_chip_data(d));
	u32 offset = irqd_to_hwirq(d);
	u32 value;
	unsigned long flags;
	void __iomem *reg = byt_gpio_reg(&vg->chip, offset, BYT_CONF0_REG);

	if (offset >= vg->chip.ngpio)
		return -EINVAL;

	spin_lock_irqsave(&vg->lock, flags);
	value = readl(reg);

	/* For level trigges the BYT_TRIG_POS and BYT_TRIG_NEG bits
	 * are used to indicate high and low level triggering
	 */
	value &= ~(BYT_TRIG_POS | BYT_TRIG_NEG | BYT_TRIG_LVL);

	switch (type) {
	case IRQ_TYPE_LEVEL_HIGH:
		value |= BYT_TRIG_LVL;
	case IRQ_TYPE_EDGE_RISING:
		value |= BYT_TRIG_POS;
		break;
	case IRQ_TYPE_LEVEL_LOW:
		value |= BYT_TRIG_LVL;
	case IRQ_TYPE_EDGE_FALLING:
		value |= BYT_TRIG_NEG;
		break;
	case IRQ_TYPE_EDGE_BOTH:
		value |= (BYT_TRIG_NEG | BYT_TRIG_POS);
		break;
	}
	writel(value, reg);

	spin_unlock_irqrestore(&vg->lock, flags);

	return 0;
}

static int byt_gpio_get(struct gpio_chip *chip, unsigned offset)
{
	void __iomem *reg = byt_gpio_reg(chip, offset, BYT_VAL_REG);
	return readl(reg) & BYT_LEVEL;
}

static void byt_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
	struct byt_gpio *vg = to_byt_gpio(chip);
	void __iomem *reg = byt_gpio_reg(chip, offset, BYT_VAL_REG);
	unsigned long flags;
	u32 old_val;

	spin_lock_irqsave(&vg->lock, flags);

	old_val = readl(reg);

	if (value)
		writel(old_val | BYT_LEVEL, reg);
	else
		writel(old_val & ~BYT_LEVEL, reg);

	spin_unlock_irqrestore(&vg->lock, flags);
}

static int byt_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
	struct byt_gpio *vg = to_byt_gpio(chip);
	void __iomem *reg = byt_gpio_reg(chip, offset, BYT_VAL_REG);
	unsigned long flags;
	u32 value;

	spin_lock_irqsave(&vg->lock, flags);

	value = readl(reg) | BYT_DIR_MASK;
	value &= ~BYT_INPUT_EN;		/* active low */
	writel(value, reg);

	spin_unlock_irqrestore(&vg->lock, flags);

	return 0;
}

static int byt_gpio_direction_output(struct gpio_chip *chip,
				     unsigned gpio, int value)
{
	struct byt_gpio *vg = to_byt_gpio(chip);
	void __iomem *conf_reg = byt_gpio_reg(chip, gpio, BYT_CONF0_REG);
	void __iomem *reg = byt_gpio_reg(chip, gpio, BYT_VAL_REG);
	unsigned long flags;
	u32 reg_val;

	spin_lock_irqsave(&vg->lock, flags);

	/*
	 * Before making any direction modifications, do a check if gpio
	 * is set for direct IRQ.  On baytrail, setting GPIO to output does
	 * not make sense, so let's at least warn the caller before they shoot
	 * themselves in the foot.
	 */
	WARN(readl(conf_reg) & BYT_DIRECT_IRQ_EN,
		"Potential Error: Setting GPIO with direct_irq_en to output");

	reg_val = readl(reg) | BYT_DIR_MASK;
	reg_val &= ~BYT_OUTPUT_EN;

	if (value)
		writel(reg_val | BYT_LEVEL, reg);
	else
		writel(reg_val & ~BYT_LEVEL, reg);

	spin_unlock_irqrestore(&vg->lock, flags);

	return 0;
}

static void byt_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
	struct byt_gpio *vg = to_byt_gpio(chip);
	int i;
	unsigned long flags;
	u32 conf0, val, offs;

	spin_lock_irqsave(&vg->lock, flags);

	for (i = 0; i < vg->chip.ngpio; i++) {
		const char *pull_str = NULL;
		const char *pull = NULL;
		const char *label;
		offs = vg->range->pins[i] * 16;
		conf0 = readl(vg->reg_base + offs + BYT_CONF0_REG);
		val = readl(vg->reg_base + offs + BYT_VAL_REG);

		label = gpiochip_is_requested(chip, i);
		if (!label)
			label = "Unrequested";

		switch (conf0 & BYT_PULL_ASSIGN_MASK) {
		case BYT_PULL_ASSIGN_UP:
			pull = "up";
			break;
		case BYT_PULL_ASSIGN_DOWN:
			pull = "down";
			break;
		}

		switch (conf0 & BYT_PULL_STR_MASK) {
		case BYT_PULL_STR_2K:
			pull_str = "2k";
			break;
		case BYT_PULL_STR_10K:
			pull_str = "10k";
			break;
		case BYT_PULL_STR_20K:
			pull_str = "20k";
			break;
		case BYT_PULL_STR_40K:
			pull_str = "40k";
			break;
		}

		seq_printf(s,
			   " gpio-%-3d (%-20.20s) %s %s %s pad-%-3d offset:0x%03x mux:%d %s%s%s",
			   i,
			   label,
			   val & BYT_INPUT_EN ? "  " : "in",
			   val & BYT_OUTPUT_EN ? "   " : "out",
			   val & BYT_LEVEL ? "hi" : "lo",
			   vg->range->pins[i], offs,
			   conf0 & 0x7,
			   conf0 & BYT_TRIG_NEG ? " fall" : "     ",
			   conf0 & BYT_TRIG_POS ? " rise" : "     ",
			   conf0 & BYT_TRIG_LVL ? " level" : "      ");

		if (pull && pull_str)
			seq_printf(s, " %-4s %-3s", pull, pull_str);
		else
			seq_puts(s, "          ");

		if (conf0 & BYT_IODEN)
			seq_puts(s, " open-drain");

		seq_puts(s, "\n");
	}
	spin_unlock_irqrestore(&vg->lock, flags);
}

static void byt_gpio_irq_handler(unsigned irq, struct irq_desc *desc)
{
	struct irq_data *data = irq_desc_get_irq_data(desc);
	struct byt_gpio *vg = to_byt_gpio(irq_desc_get_handler_data(desc));
	struct irq_chip *chip = irq_data_get_irq_chip(data);
	u32 base, pin, mask;
	void __iomem *reg;
	u32 pending;
	unsigned virq;
	int looplimit = 0;

	/* check from GPIO controller which pin triggered the interrupt */
	for (base = 0; base < vg->chip.ngpio; base += 32) {

		reg = byt_gpio_reg(&vg->chip, base, BYT_INT_STAT_REG);

		while ((pending = readl(reg))) {
			pin = __ffs(pending);
			mask = BIT(pin);
			/* Clear before handling so we can't lose an edge */
			writel(mask, reg);

			virq = irq_find_mapping(vg->chip.irqdomain, base + pin);
			generic_handle_irq(virq);

			/* In case bios or user sets triggering incorretly a pin
			 * might remain in "interrupt triggered" state.
			 */
			if (looplimit++ > 32) {
				dev_err(&vg->pdev->dev,
					"Gpio %d interrupt flood, disabling\n",
					base + pin);

				reg = byt_gpio_reg(&vg->chip, base + pin,
						   BYT_CONF0_REG);
				mask = readl(reg);
				mask &= ~(BYT_TRIG_NEG | BYT_TRIG_POS |
					  BYT_TRIG_LVL);
				writel(mask, reg);
				mask = readl(reg); /* flush */
				break;
			}
		}
	}
	chip->irq_eoi(data);
}

static void byt_irq_unmask(struct irq_data *d)
{
}

static void byt_irq_mask(struct irq_data *d)
{
}

static struct irq_chip byt_irqchip = {
	.name = "BYT-GPIO",
	.irq_mask = byt_irq_mask,
	.irq_unmask = byt_irq_unmask,
	.irq_set_type = byt_irq_type,
};

static void byt_gpio_irq_init_hw(struct byt_gpio *vg)
{
	void __iomem *reg;
	u32 base, value;

	/* clear interrupt status trigger registers */
	for (base = 0; base < vg->chip.ngpio; base += 32) {
		reg = byt_gpio_reg(&vg->chip, base, BYT_INT_STAT_REG);
		writel(0xffffffff, reg);
		/* make sure trigger bits are cleared, if not then a pin
		   might be misconfigured in bios */
		value = readl(reg);
		if (value)
			dev_err(&vg->pdev->dev,
				"GPIO interrupt error, pins misconfigured\n");
	}
}

static int byt_gpio_probe(struct platform_device *pdev)
{
	struct byt_gpio *vg;
	struct gpio_chip *gc;
	struct resource *mem_rc, *irq_rc;
	struct device *dev = &pdev->dev;
	struct acpi_device *acpi_dev;
	struct pinctrl_gpio_range *range;
	acpi_handle handle = ACPI_HANDLE(dev);
	int ret;

	if (acpi_bus_get_device(handle, &acpi_dev))
		return -ENODEV;

	vg = devm_kzalloc(dev, sizeof(struct byt_gpio), GFP_KERNEL);
	if (!vg) {
		dev_err(&pdev->dev, "can't allocate byt_gpio chip data\n");
		return -ENOMEM;
	}

	for (range = byt_ranges; range->name; range++) {
		if (!strcmp(acpi_dev->pnp.unique_id, range->name)) {
			vg->chip.ngpio = range->npins;
			vg->range = range;
			break;
		}
	}

	if (!vg->chip.ngpio || !vg->range)
		return -ENODEV;

	vg->pdev = pdev;
	platform_set_drvdata(pdev, vg);

	mem_rc = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	vg->reg_base = devm_ioremap_resource(dev, mem_rc);
	if (IS_ERR(vg->reg_base))
		return PTR_ERR(vg->reg_base);

	spin_lock_init(&vg->lock);

	gc = &vg->chip;
	gc->label = dev_name(&pdev->dev);
	gc->owner = THIS_MODULE;
	gc->request = byt_gpio_request;
	gc->free = byt_gpio_free;
	gc->direction_input = byt_gpio_direction_input;
	gc->direction_output = byt_gpio_direction_output;
	gc->get = byt_gpio_get;
	gc->set = byt_gpio_set;
	gc->dbg_show = byt_gpio_dbg_show;
	gc->base = -1;
	gc->can_sleep = false;
	gc->dev = dev;

	ret = gpiochip_add(gc);
	if (ret) {
		dev_err(&pdev->dev, "failed adding byt-gpio chip\n");
		return ret;
	}

	/* set up interrupts  */
	irq_rc = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
	if (irq_rc && irq_rc->start) {
		byt_gpio_irq_init_hw(vg);
		ret = gpiochip_irqchip_add(gc, &byt_irqchip, 0,
					   handle_simple_irq, IRQ_TYPE_NONE);
		if (ret) {
			dev_err(dev, "failed to add irqchip\n");
			gpiochip_remove(gc);
			return ret;
		}

		gpiochip_set_chained_irqchip(gc, &byt_irqchip,
					     (unsigned)irq_rc->start,
					     byt_gpio_irq_handler);
	}

	pm_runtime_enable(dev);

	return 0;
}

static int byt_gpio_runtime_suspend(struct device *dev)
{
	return 0;
}

static int byt_gpio_runtime_resume(struct device *dev)
{
	return 0;
}

static const struct dev_pm_ops byt_gpio_pm_ops = {
	.runtime_suspend = byt_gpio_runtime_suspend,
	.runtime_resume = byt_gpio_runtime_resume,
};

static const struct acpi_device_id byt_gpio_acpi_match[] = {
	{ "INT33B2", 0 },
	{ "INT33FC", 0 },
	{ }
};
MODULE_DEVICE_TABLE(acpi, byt_gpio_acpi_match);

static int byt_gpio_remove(struct platform_device *pdev)
{
	struct byt_gpio *vg = platform_get_drvdata(pdev);

	pm_runtime_disable(&pdev->dev);
	gpiochip_remove(&vg->chip);

	return 0;
}

static struct platform_driver byt_gpio_driver = {
	.probe          = byt_gpio_probe,
	.remove         = byt_gpio_remove,
	.driver         = {
		.name   = "byt_gpio",
		.owner  = THIS_MODULE,
		.pm	= &byt_gpio_pm_ops,
		.acpi_match_table = ACPI_PTR(byt_gpio_acpi_match),
	},
};

static int __init byt_gpio_init(void)
{
	return platform_driver_register(&byt_gpio_driver);
}

subsys_initcall(byt_gpio_init);