xref: /openbmc/linux/drivers/gpio/gpio-pch.c (revision 6d99a79c)
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/driver.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 =	gpiochip_get_data(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 =	gpiochip_get_data(gpio);
129 
130 	return (ioread32(&chip->reg->pi) >> nr) & 1;
131 }
132 
133 static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
134 				     int val)
135 {
136 	struct pch_gpio *chip =	gpiochip_get_data(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 =	gpiochip_get_data(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 #ifdef CONFIG_PM
175 /*
176  * Save register configuration and disable interrupts.
177  */
178 static void pch_gpio_save_reg_conf(struct pch_gpio *chip)
179 {
180 	chip->pch_gpio_reg.ien_reg = ioread32(&chip->reg->ien);
181 	chip->pch_gpio_reg.imask_reg = ioread32(&chip->reg->imask);
182 	chip->pch_gpio_reg.po_reg = ioread32(&chip->reg->po);
183 	chip->pch_gpio_reg.pm_reg = ioread32(&chip->reg->pm);
184 	chip->pch_gpio_reg.im0_reg = ioread32(&chip->reg->im0);
185 	if (chip->ioh == INTEL_EG20T_PCH)
186 		chip->pch_gpio_reg.im1_reg = ioread32(&chip->reg->im1);
187 	if (chip->ioh == OKISEMI_ML7223n_IOH)
188 		chip->pch_gpio_reg.gpio_use_sel_reg =\
189 					    ioread32(&chip->reg->gpio_use_sel);
190 }
191 
192 /*
193  * This function restores the register configuration of the GPIO device.
194  */
195 static void pch_gpio_restore_reg_conf(struct pch_gpio *chip)
196 {
197 	iowrite32(chip->pch_gpio_reg.ien_reg, &chip->reg->ien);
198 	iowrite32(chip->pch_gpio_reg.imask_reg, &chip->reg->imask);
199 	/* to store contents of PO register */
200 	iowrite32(chip->pch_gpio_reg.po_reg, &chip->reg->po);
201 	/* to store contents of PM register */
202 	iowrite32(chip->pch_gpio_reg.pm_reg, &chip->reg->pm);
203 	iowrite32(chip->pch_gpio_reg.im0_reg, &chip->reg->im0);
204 	if (chip->ioh == INTEL_EG20T_PCH)
205 		iowrite32(chip->pch_gpio_reg.im1_reg, &chip->reg->im1);
206 	if (chip->ioh == OKISEMI_ML7223n_IOH)
207 		iowrite32(chip->pch_gpio_reg.gpio_use_sel_reg,
208 			  &chip->reg->gpio_use_sel);
209 }
210 #endif
211 
212 static int pch_gpio_to_irq(struct gpio_chip *gpio, unsigned offset)
213 {
214 	struct pch_gpio *chip = gpiochip_get_data(gpio);
215 	return chip->irq_base + offset;
216 }
217 
218 static void pch_gpio_setup(struct pch_gpio *chip)
219 {
220 	struct gpio_chip *gpio = &chip->gpio;
221 
222 	gpio->label = dev_name(chip->dev);
223 	gpio->parent = chip->dev;
224 	gpio->owner = THIS_MODULE;
225 	gpio->direction_input = pch_gpio_direction_input;
226 	gpio->get = pch_gpio_get;
227 	gpio->direction_output = pch_gpio_direction_output;
228 	gpio->set = pch_gpio_set;
229 	gpio->dbg_show = NULL;
230 	gpio->base = -1;
231 	gpio->ngpio = gpio_pins[chip->ioh];
232 	gpio->can_sleep = false;
233 	gpio->to_irq = pch_gpio_to_irq;
234 }
235 
236 static int pch_irq_type(struct irq_data *d, unsigned int type)
237 {
238 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
239 	struct pch_gpio *chip = gc->private;
240 	u32 im, im_pos, val;
241 	u32 __iomem *im_reg;
242 	unsigned long flags;
243 	int ch, irq = d->irq;
244 
245 	ch = irq - chip->irq_base;
246 	if (irq <= chip->irq_base + 7) {
247 		im_reg = &chip->reg->im0;
248 		im_pos = ch;
249 	} else {
250 		im_reg = &chip->reg->im1;
251 		im_pos = ch - 8;
252 	}
253 	dev_dbg(chip->dev, "%s:irq=%d type=%d ch=%d pos=%d\n",
254 		__func__, irq, type, ch, im_pos);
255 
256 	spin_lock_irqsave(&chip->spinlock, flags);
257 
258 	switch (type) {
259 	case IRQ_TYPE_EDGE_RISING:
260 		val = PCH_EDGE_RISING;
261 		break;
262 	case IRQ_TYPE_EDGE_FALLING:
263 		val = PCH_EDGE_FALLING;
264 		break;
265 	case IRQ_TYPE_EDGE_BOTH:
266 		val = PCH_EDGE_BOTH;
267 		break;
268 	case IRQ_TYPE_LEVEL_HIGH:
269 		val = PCH_LEVEL_H;
270 		break;
271 	case IRQ_TYPE_LEVEL_LOW:
272 		val = PCH_LEVEL_L;
273 		break;
274 	default:
275 		goto unlock;
276 	}
277 
278 	/* Set interrupt mode */
279 	im = ioread32(im_reg) & ~(PCH_IM_MASK << (im_pos * 4));
280 	iowrite32(im | (val << (im_pos * 4)), im_reg);
281 
282 	/* And the handler */
283 	if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
284 		irq_set_handler_locked(d, handle_level_irq);
285 	else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
286 		irq_set_handler_locked(d, handle_edge_irq);
287 
288 unlock:
289 	spin_unlock_irqrestore(&chip->spinlock, flags);
290 	return 0;
291 }
292 
293 static void pch_irq_unmask(struct irq_data *d)
294 {
295 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
296 	struct pch_gpio *chip = gc->private;
297 
298 	iowrite32(1 << (d->irq - chip->irq_base), &chip->reg->imaskclr);
299 }
300 
301 static void pch_irq_mask(struct irq_data *d)
302 {
303 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
304 	struct pch_gpio *chip = gc->private;
305 
306 	iowrite32(1 << (d->irq - chip->irq_base), &chip->reg->imask);
307 }
308 
309 static void pch_irq_ack(struct irq_data *d)
310 {
311 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
312 	struct pch_gpio *chip = gc->private;
313 
314 	iowrite32(1 << (d->irq - chip->irq_base), &chip->reg->iclr);
315 }
316 
317 static irqreturn_t pch_gpio_handler(int irq, void *dev_id)
318 {
319 	struct pch_gpio *chip = dev_id;
320 	u32 reg_val = ioread32(&chip->reg->istatus);
321 	int i, ret = IRQ_NONE;
322 
323 	for (i = 0; i < gpio_pins[chip->ioh]; i++) {
324 		if (reg_val & BIT(i)) {
325 			dev_dbg(chip->dev, "%s:[%d]:irq=%d  status=0x%x\n",
326 				__func__, i, irq, reg_val);
327 			generic_handle_irq(chip->irq_base + i);
328 			ret = IRQ_HANDLED;
329 		}
330 	}
331 	return ret;
332 }
333 
334 static int pch_gpio_alloc_generic_chip(struct pch_gpio *chip,
335 				       unsigned int irq_start,
336 				       unsigned int num)
337 {
338 	struct irq_chip_generic *gc;
339 	struct irq_chip_type *ct;
340 	int rv;
341 
342 	gc = devm_irq_alloc_generic_chip(chip->dev, "pch_gpio", 1, irq_start,
343 					 chip->base, handle_simple_irq);
344 	if (!gc)
345 		return -ENOMEM;
346 
347 	gc->private = chip;
348 	ct = gc->chip_types;
349 
350 	ct->chip.irq_ack = pch_irq_ack;
351 	ct->chip.irq_mask = pch_irq_mask;
352 	ct->chip.irq_unmask = pch_irq_unmask;
353 	ct->chip.irq_set_type = pch_irq_type;
354 
355 	rv = devm_irq_setup_generic_chip(chip->dev, gc, IRQ_MSK(num),
356 					 IRQ_GC_INIT_MASK_CACHE,
357 					 IRQ_NOREQUEST | IRQ_NOPROBE, 0);
358 
359 	return rv;
360 }
361 
362 static int pch_gpio_probe(struct pci_dev *pdev,
363 				    const struct pci_device_id *id)
364 {
365 	s32 ret;
366 	struct pch_gpio *chip;
367 	int irq_base;
368 	u32 msk;
369 
370 	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
371 	if (chip == NULL)
372 		return -ENOMEM;
373 
374 	chip->dev = &pdev->dev;
375 	ret = pci_enable_device(pdev);
376 	if (ret) {
377 		dev_err(&pdev->dev, "%s : pci_enable_device FAILED", __func__);
378 		goto err_pci_enable;
379 	}
380 
381 	ret = pci_request_regions(pdev, KBUILD_MODNAME);
382 	if (ret) {
383 		dev_err(&pdev->dev, "pci_request_regions FAILED-%d", ret);
384 		goto err_request_regions;
385 	}
386 
387 	chip->base = pci_iomap(pdev, 1, 0);
388 	if (!chip->base) {
389 		dev_err(&pdev->dev, "%s : pci_iomap FAILED", __func__);
390 		ret = -ENOMEM;
391 		goto err_iomap;
392 	}
393 
394 	if (pdev->device == 0x8803)
395 		chip->ioh = INTEL_EG20T_PCH;
396 	else if (pdev->device == 0x8014)
397 		chip->ioh = OKISEMI_ML7223m_IOH;
398 	else if (pdev->device == 0x8043)
399 		chip->ioh = OKISEMI_ML7223n_IOH;
400 
401 	chip->reg = chip->base;
402 	pci_set_drvdata(pdev, chip);
403 	spin_lock_init(&chip->spinlock);
404 	pch_gpio_setup(chip);
405 #ifdef CONFIG_OF_GPIO
406 	chip->gpio.of_node = pdev->dev.of_node;
407 #endif
408 	ret = gpiochip_add_data(&chip->gpio, chip);
409 	if (ret) {
410 		dev_err(&pdev->dev, "PCH gpio: Failed to register GPIO\n");
411 		goto err_gpiochip_add;
412 	}
413 
414 	irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0,
415 					gpio_pins[chip->ioh], NUMA_NO_NODE);
416 	if (irq_base < 0) {
417 		dev_warn(&pdev->dev, "PCH gpio: Failed to get IRQ base num\n");
418 		chip->irq_base = -1;
419 		goto end;
420 	}
421 	chip->irq_base = irq_base;
422 
423 	/* Mask all interrupts, but enable them */
424 	msk = (1 << gpio_pins[chip->ioh]) - 1;
425 	iowrite32(msk, &chip->reg->imask);
426 	iowrite32(msk, &chip->reg->ien);
427 
428 	ret = devm_request_irq(&pdev->dev, pdev->irq, pch_gpio_handler,
429 			       IRQF_SHARED, KBUILD_MODNAME, chip);
430 	if (ret != 0) {
431 		dev_err(&pdev->dev,
432 			"%s request_irq failed\n", __func__);
433 		goto err_request_irq;
434 	}
435 
436 	ret = pch_gpio_alloc_generic_chip(chip, irq_base,
437 					  gpio_pins[chip->ioh]);
438 	if (ret)
439 		goto err_request_irq;
440 
441 end:
442 	return 0;
443 
444 err_request_irq:
445 	gpiochip_remove(&chip->gpio);
446 
447 err_gpiochip_add:
448 	pci_iounmap(pdev, chip->base);
449 
450 err_iomap:
451 	pci_release_regions(pdev);
452 
453 err_request_regions:
454 	pci_disable_device(pdev);
455 
456 err_pci_enable:
457 	kfree(chip);
458 	dev_err(&pdev->dev, "%s Failed returns %d\n", __func__, ret);
459 	return ret;
460 }
461 
462 static void pch_gpio_remove(struct pci_dev *pdev)
463 {
464 	struct pch_gpio *chip = pci_get_drvdata(pdev);
465 
466 	gpiochip_remove(&chip->gpio);
467 	pci_iounmap(pdev, chip->base);
468 	pci_release_regions(pdev);
469 	pci_disable_device(pdev);
470 	kfree(chip);
471 }
472 
473 #ifdef CONFIG_PM
474 static int pch_gpio_suspend(struct pci_dev *pdev, pm_message_t state)
475 {
476 	s32 ret;
477 	struct pch_gpio *chip = pci_get_drvdata(pdev);
478 	unsigned long flags;
479 
480 	spin_lock_irqsave(&chip->spinlock, flags);
481 	pch_gpio_save_reg_conf(chip);
482 	spin_unlock_irqrestore(&chip->spinlock, flags);
483 
484 	ret = pci_save_state(pdev);
485 	if (ret) {
486 		dev_err(&pdev->dev, "pci_save_state Failed-%d\n", ret);
487 		return ret;
488 	}
489 	pci_disable_device(pdev);
490 	pci_set_power_state(pdev, PCI_D0);
491 	ret = pci_enable_wake(pdev, PCI_D0, 1);
492 	if (ret)
493 		dev_err(&pdev->dev, "pci_enable_wake Failed -%d\n", ret);
494 
495 	return 0;
496 }
497 
498 static int pch_gpio_resume(struct pci_dev *pdev)
499 {
500 	s32 ret;
501 	struct pch_gpio *chip = pci_get_drvdata(pdev);
502 	unsigned long flags;
503 
504 	ret = pci_enable_wake(pdev, PCI_D0, 0);
505 
506 	pci_set_power_state(pdev, PCI_D0);
507 	ret = pci_enable_device(pdev);
508 	if (ret) {
509 		dev_err(&pdev->dev, "pci_enable_device Failed-%d ", ret);
510 		return ret;
511 	}
512 	pci_restore_state(pdev);
513 
514 	spin_lock_irqsave(&chip->spinlock, flags);
515 	iowrite32(0x01, &chip->reg->reset);
516 	iowrite32(0x00, &chip->reg->reset);
517 	pch_gpio_restore_reg_conf(chip);
518 	spin_unlock_irqrestore(&chip->spinlock, flags);
519 
520 	return 0;
521 }
522 #else
523 #define pch_gpio_suspend NULL
524 #define pch_gpio_resume NULL
525 #endif
526 
527 #define PCI_VENDOR_ID_ROHM             0x10DB
528 static const struct pci_device_id pch_gpio_pcidev_id[] = {
529 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8803) },
530 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8014) },
531 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8043) },
532 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8803) },
533 	{ 0, }
534 };
535 MODULE_DEVICE_TABLE(pci, pch_gpio_pcidev_id);
536 
537 static struct pci_driver pch_gpio_driver = {
538 	.name = "pch_gpio",
539 	.id_table = pch_gpio_pcidev_id,
540 	.probe = pch_gpio_probe,
541 	.remove = pch_gpio_remove,
542 	.suspend = pch_gpio_suspend,
543 	.resume = pch_gpio_resume
544 };
545 
546 module_pci_driver(pch_gpio_driver);
547 
548 MODULE_DESCRIPTION("PCH GPIO PCI Driver");
549 MODULE_LICENSE("GPL");
550