xref: /openbmc/linux/drivers/gpio/gpio-pch.c (revision d2168146)
1 /*
2  * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; version 2 of the License.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program; if not, write to the Free Software
15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
16  */
17 #include <linux/module.h>
18 #include <linux/kernel.h>
19 #include <linux/pci.h>
20 #include <linux/gpio.h>
21 #include <linux/interrupt.h>
22 #include <linux/irq.h>
23 #include <linux/slab.h>
24 
25 #define PCH_EDGE_FALLING	0
26 #define PCH_EDGE_RISING		BIT(0)
27 #define PCH_LEVEL_L		BIT(1)
28 #define PCH_LEVEL_H		(BIT(0) | BIT(1))
29 #define PCH_EDGE_BOTH		BIT(2)
30 #define PCH_IM_MASK		(BIT(0) | BIT(1) | BIT(2))
31 
32 #define PCH_IRQ_BASE		24
33 
34 struct pch_regs {
35 	u32	ien;
36 	u32	istatus;
37 	u32	idisp;
38 	u32	iclr;
39 	u32	imask;
40 	u32	imaskclr;
41 	u32	po;
42 	u32	pi;
43 	u32	pm;
44 	u32	im0;
45 	u32	im1;
46 	u32	reserved[3];
47 	u32	gpio_use_sel;
48 	u32	reset;
49 };
50 
51 enum pch_type_t {
52 	INTEL_EG20T_PCH,
53 	OKISEMI_ML7223m_IOH, /* LAPIS Semiconductor ML7223 IOH PCIe Bus-m */
54 	OKISEMI_ML7223n_IOH  /* LAPIS Semiconductor ML7223 IOH PCIe Bus-n */
55 };
56 
57 /* Specifies number of GPIO PINS */
58 static int gpio_pins[] = {
59 	[INTEL_EG20T_PCH] = 12,
60 	[OKISEMI_ML7223m_IOH] = 8,
61 	[OKISEMI_ML7223n_IOH] = 8,
62 };
63 
64 /**
65  * struct pch_gpio_reg_data - The register store data.
66  * @ien_reg:	To store contents of IEN register.
67  * @imask_reg:	To store contents of IMASK register.
68  * @po_reg:	To store contents of PO register.
69  * @pm_reg:	To store contents of PM register.
70  * @im0_reg:	To store contents of IM0 register.
71  * @im1_reg:	To store contents of IM1 register.
72  * @gpio_use_sel_reg : To store contents of GPIO_USE_SEL register.
73  *		       (Only ML7223 Bus-n)
74  */
75 struct pch_gpio_reg_data {
76 	u32 ien_reg;
77 	u32 imask_reg;
78 	u32 po_reg;
79 	u32 pm_reg;
80 	u32 im0_reg;
81 	u32 im1_reg;
82 	u32 gpio_use_sel_reg;
83 };
84 
85 /**
86  * struct pch_gpio - GPIO private data structure.
87  * @base:			PCI base address of Memory mapped I/O register.
88  * @reg:			Memory mapped PCH GPIO register list.
89  * @dev:			Pointer to device structure.
90  * @gpio:			Data for GPIO infrastructure.
91  * @pch_gpio_reg:		Memory mapped Register data is saved here
92  *				when suspend.
93  * @lock:			Used for register access protection
94  * @irq_base:		Save base of IRQ number for interrupt
95  * @ioh:		IOH ID
96  * @spinlock:		Used for register access protection
97  */
98 struct pch_gpio {
99 	void __iomem *base;
100 	struct pch_regs __iomem *reg;
101 	struct device *dev;
102 	struct gpio_chip gpio;
103 	struct pch_gpio_reg_data pch_gpio_reg;
104 	int irq_base;
105 	enum pch_type_t ioh;
106 	spinlock_t spinlock;
107 };
108 
109 static void pch_gpio_set(struct gpio_chip *gpio, unsigned nr, int val)
110 {
111 	u32 reg_val;
112 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
113 	unsigned long flags;
114 
115 	spin_lock_irqsave(&chip->spinlock, flags);
116 	reg_val = ioread32(&chip->reg->po);
117 	if (val)
118 		reg_val |= (1 << nr);
119 	else
120 		reg_val &= ~(1 << nr);
121 
122 	iowrite32(reg_val, &chip->reg->po);
123 	spin_unlock_irqrestore(&chip->spinlock, flags);
124 }
125 
126 static int pch_gpio_get(struct gpio_chip *gpio, unsigned nr)
127 {
128 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
129 
130 	return ioread32(&chip->reg->pi) & (1 << nr);
131 }
132 
133 static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
134 				     int val)
135 {
136 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
137 	u32 pm;
138 	u32 reg_val;
139 	unsigned long flags;
140 
141 	spin_lock_irqsave(&chip->spinlock, flags);
142 
143 	reg_val = ioread32(&chip->reg->po);
144 	if (val)
145 		reg_val |= (1 << nr);
146 	else
147 		reg_val &= ~(1 << nr);
148 	iowrite32(reg_val, &chip->reg->po);
149 
150 	pm = ioread32(&chip->reg->pm) & ((1 << gpio_pins[chip->ioh]) - 1);
151 	pm |= (1 << nr);
152 	iowrite32(pm, &chip->reg->pm);
153 
154 	spin_unlock_irqrestore(&chip->spinlock, flags);
155 
156 	return 0;
157 }
158 
159 static int pch_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
160 {
161 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
162 	u32 pm;
163 	unsigned long flags;
164 
165 	spin_lock_irqsave(&chip->spinlock, flags);
166 	pm = ioread32(&chip->reg->pm) & ((1 << gpio_pins[chip->ioh]) - 1);
167 	pm &= ~(1 << nr);
168 	iowrite32(pm, &chip->reg->pm);
169 	spin_unlock_irqrestore(&chip->spinlock, flags);
170 
171 	return 0;
172 }
173 
174 /*
175  * Save register configuration and disable interrupts.
176  */
177 static void pch_gpio_save_reg_conf(struct pch_gpio *chip)
178 {
179 	chip->pch_gpio_reg.ien_reg = ioread32(&chip->reg->ien);
180 	chip->pch_gpio_reg.imask_reg = ioread32(&chip->reg->imask);
181 	chip->pch_gpio_reg.po_reg = ioread32(&chip->reg->po);
182 	chip->pch_gpio_reg.pm_reg = ioread32(&chip->reg->pm);
183 	chip->pch_gpio_reg.im0_reg = ioread32(&chip->reg->im0);
184 	if (chip->ioh == INTEL_EG20T_PCH)
185 		chip->pch_gpio_reg.im1_reg = ioread32(&chip->reg->im1);
186 	if (chip->ioh == OKISEMI_ML7223n_IOH)
187 		chip->pch_gpio_reg.gpio_use_sel_reg =\
188 					    ioread32(&chip->reg->gpio_use_sel);
189 }
190 
191 /*
192  * This function restores the register configuration of the GPIO device.
193  */
194 static void pch_gpio_restore_reg_conf(struct pch_gpio *chip)
195 {
196 	iowrite32(chip->pch_gpio_reg.ien_reg, &chip->reg->ien);
197 	iowrite32(chip->pch_gpio_reg.imask_reg, &chip->reg->imask);
198 	/* to store contents of PO register */
199 	iowrite32(chip->pch_gpio_reg.po_reg, &chip->reg->po);
200 	/* to store contents of PM register */
201 	iowrite32(chip->pch_gpio_reg.pm_reg, &chip->reg->pm);
202 	iowrite32(chip->pch_gpio_reg.im0_reg, &chip->reg->im0);
203 	if (chip->ioh == INTEL_EG20T_PCH)
204 		iowrite32(chip->pch_gpio_reg.im1_reg, &chip->reg->im1);
205 	if (chip->ioh == OKISEMI_ML7223n_IOH)
206 		iowrite32(chip->pch_gpio_reg.gpio_use_sel_reg,
207 			  &chip->reg->gpio_use_sel);
208 }
209 
210 static int pch_gpio_to_irq(struct gpio_chip *gpio, unsigned offset)
211 {
212 	struct pch_gpio *chip = container_of(gpio, struct pch_gpio, gpio);
213 	return chip->irq_base + offset;
214 }
215 
216 static void pch_gpio_setup(struct pch_gpio *chip)
217 {
218 	struct gpio_chip *gpio = &chip->gpio;
219 
220 	gpio->label = dev_name(chip->dev);
221 	gpio->dev = chip->dev;
222 	gpio->owner = THIS_MODULE;
223 	gpio->direction_input = pch_gpio_direction_input;
224 	gpio->get = pch_gpio_get;
225 	gpio->direction_output = pch_gpio_direction_output;
226 	gpio->set = pch_gpio_set;
227 	gpio->dbg_show = NULL;
228 	gpio->base = -1;
229 	gpio->ngpio = gpio_pins[chip->ioh];
230 	gpio->can_sleep = false;
231 	gpio->to_irq = pch_gpio_to_irq;
232 }
233 
234 static int pch_irq_type(struct irq_data *d, unsigned int type)
235 {
236 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
237 	struct pch_gpio *chip = gc->private;
238 	u32 im, im_pos, val;
239 	u32 __iomem *im_reg;
240 	unsigned long flags;
241 	int ch, irq = d->irq;
242 
243 	ch = irq - chip->irq_base;
244 	if (irq <= chip->irq_base + 7) {
245 		im_reg = &chip->reg->im0;
246 		im_pos = ch;
247 	} else {
248 		im_reg = &chip->reg->im1;
249 		im_pos = ch - 8;
250 	}
251 	dev_dbg(chip->dev, "%s:irq=%d type=%d ch=%d pos=%d\n",
252 		__func__, irq, type, ch, im_pos);
253 
254 	spin_lock_irqsave(&chip->spinlock, flags);
255 
256 	switch (type) {
257 	case IRQ_TYPE_EDGE_RISING:
258 		val = PCH_EDGE_RISING;
259 		break;
260 	case IRQ_TYPE_EDGE_FALLING:
261 		val = PCH_EDGE_FALLING;
262 		break;
263 	case IRQ_TYPE_EDGE_BOTH:
264 		val = PCH_EDGE_BOTH;
265 		break;
266 	case IRQ_TYPE_LEVEL_HIGH:
267 		val = PCH_LEVEL_H;
268 		break;
269 	case IRQ_TYPE_LEVEL_LOW:
270 		val = PCH_LEVEL_L;
271 		break;
272 	default:
273 		goto unlock;
274 	}
275 
276 	/* Set interrupt mode */
277 	im = ioread32(im_reg) & ~(PCH_IM_MASK << (im_pos * 4));
278 	iowrite32(im | (val << (im_pos * 4)), im_reg);
279 
280 	/* And the handler */
281 	if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
282 		__irq_set_handler_locked(d->irq, handle_level_irq);
283 	else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
284 		__irq_set_handler_locked(d->irq, handle_edge_irq);
285 
286 unlock:
287 	spin_unlock_irqrestore(&chip->spinlock, flags);
288 	return 0;
289 }
290 
291 static void pch_irq_unmask(struct irq_data *d)
292 {
293 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
294 	struct pch_gpio *chip = gc->private;
295 
296 	iowrite32(1 << (d->irq - chip->irq_base), &chip->reg->imaskclr);
297 }
298 
299 static void pch_irq_mask(struct irq_data *d)
300 {
301 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
302 	struct pch_gpio *chip = gc->private;
303 
304 	iowrite32(1 << (d->irq - chip->irq_base), &chip->reg->imask);
305 }
306 
307 static void pch_irq_ack(struct irq_data *d)
308 {
309 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
310 	struct pch_gpio *chip = gc->private;
311 
312 	iowrite32(1 << (d->irq - chip->irq_base), &chip->reg->iclr);
313 }
314 
315 static irqreturn_t pch_gpio_handler(int irq, void *dev_id)
316 {
317 	struct pch_gpio *chip = dev_id;
318 	u32 reg_val = ioread32(&chip->reg->istatus);
319 	int i, ret = IRQ_NONE;
320 
321 	for (i = 0; i < gpio_pins[chip->ioh]; i++) {
322 		if (reg_val & BIT(i)) {
323 			dev_dbg(chip->dev, "%s:[%d]:irq=%d  status=0x%x\n",
324 				__func__, i, irq, reg_val);
325 			generic_handle_irq(chip->irq_base + i);
326 			ret = IRQ_HANDLED;
327 		}
328 	}
329 	return ret;
330 }
331 
332 static void pch_gpio_alloc_generic_chip(struct pch_gpio *chip,
333 				unsigned int irq_start, unsigned int num)
334 {
335 	struct irq_chip_generic *gc;
336 	struct irq_chip_type *ct;
337 
338 	gc = irq_alloc_generic_chip("pch_gpio", 1, irq_start, chip->base,
339 				    handle_simple_irq);
340 	gc->private = chip;
341 	ct = gc->chip_types;
342 
343 	ct->chip.irq_ack = pch_irq_ack;
344 	ct->chip.irq_mask = pch_irq_mask;
345 	ct->chip.irq_unmask = pch_irq_unmask;
346 	ct->chip.irq_set_type = pch_irq_type;
347 
348 	irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
349 			       IRQ_NOREQUEST | IRQ_NOPROBE, 0);
350 }
351 
352 static int pch_gpio_probe(struct pci_dev *pdev,
353 				    const struct pci_device_id *id)
354 {
355 	s32 ret;
356 	struct pch_gpio *chip;
357 	int irq_base;
358 	u32 msk;
359 
360 	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
361 	if (chip == NULL)
362 		return -ENOMEM;
363 
364 	chip->dev = &pdev->dev;
365 	ret = pci_enable_device(pdev);
366 	if (ret) {
367 		dev_err(&pdev->dev, "%s : pci_enable_device FAILED", __func__);
368 		goto err_pci_enable;
369 	}
370 
371 	ret = pci_request_regions(pdev, KBUILD_MODNAME);
372 	if (ret) {
373 		dev_err(&pdev->dev, "pci_request_regions FAILED-%d", ret);
374 		goto err_request_regions;
375 	}
376 
377 	chip->base = pci_iomap(pdev, 1, 0);
378 	if (!chip->base) {
379 		dev_err(&pdev->dev, "%s : pci_iomap FAILED", __func__);
380 		ret = -ENOMEM;
381 		goto err_iomap;
382 	}
383 
384 	if (pdev->device == 0x8803)
385 		chip->ioh = INTEL_EG20T_PCH;
386 	else if (pdev->device == 0x8014)
387 		chip->ioh = OKISEMI_ML7223m_IOH;
388 	else if (pdev->device == 0x8043)
389 		chip->ioh = OKISEMI_ML7223n_IOH;
390 
391 	chip->reg = chip->base;
392 	pci_set_drvdata(pdev, chip);
393 	spin_lock_init(&chip->spinlock);
394 	pch_gpio_setup(chip);
395 	ret = gpiochip_add(&chip->gpio);
396 	if (ret) {
397 		dev_err(&pdev->dev, "PCH gpio: Failed to register GPIO\n");
398 		goto err_gpiochip_add;
399 	}
400 
401 	irq_base = irq_alloc_descs(-1, 0, gpio_pins[chip->ioh], NUMA_NO_NODE);
402 	if (irq_base < 0) {
403 		dev_warn(&pdev->dev, "PCH gpio: Failed to get IRQ base num\n");
404 		chip->irq_base = -1;
405 		goto end;
406 	}
407 	chip->irq_base = irq_base;
408 
409 	/* Mask all interrupts, but enable them */
410 	msk = (1 << gpio_pins[chip->ioh]) - 1;
411 	iowrite32(msk, &chip->reg->imask);
412 	iowrite32(msk, &chip->reg->ien);
413 
414 	ret = request_irq(pdev->irq, pch_gpio_handler,
415 			  IRQF_SHARED, KBUILD_MODNAME, chip);
416 	if (ret != 0) {
417 		dev_err(&pdev->dev,
418 			"%s request_irq failed\n", __func__);
419 		goto err_request_irq;
420 	}
421 
422 	pch_gpio_alloc_generic_chip(chip, irq_base, gpio_pins[chip->ioh]);
423 
424 end:
425 	return 0;
426 
427 err_request_irq:
428 	irq_free_descs(irq_base, gpio_pins[chip->ioh]);
429 
430 	if (gpiochip_remove(&chip->gpio))
431 		dev_err(&pdev->dev, "%s gpiochip_remove failed\n", __func__);
432 
433 err_gpiochip_add:
434 	pci_iounmap(pdev, chip->base);
435 
436 err_iomap:
437 	pci_release_regions(pdev);
438 
439 err_request_regions:
440 	pci_disable_device(pdev);
441 
442 err_pci_enable:
443 	kfree(chip);
444 	dev_err(&pdev->dev, "%s Failed returns %d\n", __func__, ret);
445 	return ret;
446 }
447 
448 static void pch_gpio_remove(struct pci_dev *pdev)
449 {
450 	int err;
451 	struct pch_gpio *chip = pci_get_drvdata(pdev);
452 
453 	if (chip->irq_base != -1) {
454 		free_irq(pdev->irq, chip);
455 
456 		irq_free_descs(chip->irq_base, gpio_pins[chip->ioh]);
457 	}
458 
459 	err = gpiochip_remove(&chip->gpio);
460 	if (err)
461 		dev_err(&pdev->dev, "Failed gpiochip_remove\n");
462 
463 	pci_iounmap(pdev, chip->base);
464 	pci_release_regions(pdev);
465 	pci_disable_device(pdev);
466 	kfree(chip);
467 }
468 
469 #ifdef CONFIG_PM
470 static int pch_gpio_suspend(struct pci_dev *pdev, pm_message_t state)
471 {
472 	s32 ret;
473 	struct pch_gpio *chip = pci_get_drvdata(pdev);
474 	unsigned long flags;
475 
476 	spin_lock_irqsave(&chip->spinlock, flags);
477 	pch_gpio_save_reg_conf(chip);
478 	spin_unlock_irqrestore(&chip->spinlock, flags);
479 
480 	ret = pci_save_state(pdev);
481 	if (ret) {
482 		dev_err(&pdev->dev, "pci_save_state Failed-%d\n", ret);
483 		return ret;
484 	}
485 	pci_disable_device(pdev);
486 	pci_set_power_state(pdev, PCI_D0);
487 	ret = pci_enable_wake(pdev, PCI_D0, 1);
488 	if (ret)
489 		dev_err(&pdev->dev, "pci_enable_wake Failed -%d\n", ret);
490 
491 	return 0;
492 }
493 
494 static int pch_gpio_resume(struct pci_dev *pdev)
495 {
496 	s32 ret;
497 	struct pch_gpio *chip = pci_get_drvdata(pdev);
498 	unsigned long flags;
499 
500 	ret = pci_enable_wake(pdev, PCI_D0, 0);
501 
502 	pci_set_power_state(pdev, PCI_D0);
503 	ret = pci_enable_device(pdev);
504 	if (ret) {
505 		dev_err(&pdev->dev, "pci_enable_device Failed-%d ", ret);
506 		return ret;
507 	}
508 	pci_restore_state(pdev);
509 
510 	spin_lock_irqsave(&chip->spinlock, flags);
511 	iowrite32(0x01, &chip->reg->reset);
512 	iowrite32(0x00, &chip->reg->reset);
513 	pch_gpio_restore_reg_conf(chip);
514 	spin_unlock_irqrestore(&chip->spinlock, flags);
515 
516 	return 0;
517 }
518 #else
519 #define pch_gpio_suspend NULL
520 #define pch_gpio_resume NULL
521 #endif
522 
523 #define PCI_VENDOR_ID_ROHM             0x10DB
524 static const struct pci_device_id pch_gpio_pcidev_id[] = {
525 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8803) },
526 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8014) },
527 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8043) },
528 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8803) },
529 	{ 0, }
530 };
531 MODULE_DEVICE_TABLE(pci, pch_gpio_pcidev_id);
532 
533 static struct pci_driver pch_gpio_driver = {
534 	.name = "pch_gpio",
535 	.id_table = pch_gpio_pcidev_id,
536 	.probe = pch_gpio_probe,
537 	.remove = pch_gpio_remove,
538 	.suspend = pch_gpio_suspend,
539 	.resume = pch_gpio_resume
540 };
541 
542 module_pci_driver(pch_gpio_driver);
543 
544 MODULE_DESCRIPTION("PCH GPIO PCI Driver");
545 MODULE_LICENSE("GPL");
546