xref: /openbmc/linux/drivers/gpio/gpio-pch.c (revision e23feb16)
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 
24 #define PCH_EDGE_FALLING	0
25 #define PCH_EDGE_RISING		BIT(0)
26 #define PCH_LEVEL_L		BIT(1)
27 #define PCH_LEVEL_H		(BIT(0) | BIT(1))
28 #define PCH_EDGE_BOTH		BIT(2)
29 #define PCH_IM_MASK		(BIT(0) | BIT(1) | BIT(2))
30 
31 #define PCH_IRQ_BASE		24
32 
33 struct pch_regs {
34 	u32	ien;
35 	u32	istatus;
36 	u32	idisp;
37 	u32	iclr;
38 	u32	imask;
39 	u32	imaskclr;
40 	u32	po;
41 	u32	pi;
42 	u32	pm;
43 	u32	im0;
44 	u32	im1;
45 	u32	reserved[3];
46 	u32	gpio_use_sel;
47 	u32	reset;
48 };
49 
50 enum pch_type_t {
51 	INTEL_EG20T_PCH,
52 	OKISEMI_ML7223m_IOH, /* LAPIS Semiconductor ML7223 IOH PCIe Bus-m */
53 	OKISEMI_ML7223n_IOH  /* LAPIS Semiconductor ML7223 IOH PCIe Bus-n */
54 };
55 
56 /* Specifies number of GPIO PINS */
57 static int gpio_pins[] = {
58 	[INTEL_EG20T_PCH] = 12,
59 	[OKISEMI_ML7223m_IOH] = 8,
60 	[OKISEMI_ML7223n_IOH] = 8,
61 };
62 
63 /**
64  * struct pch_gpio_reg_data - The register store data.
65  * @ien_reg:	To store contents of IEN register.
66  * @imask_reg:	To store contents of IMASK register.
67  * @po_reg:	To store contents of PO register.
68  * @pm_reg:	To store contents of PM register.
69  * @im0_reg:	To store contents of IM0 register.
70  * @im1_reg:	To store contents of IM1 register.
71  * @gpio_use_sel_reg : To store contents of GPIO_USE_SEL register.
72  *		       (Only ML7223 Bus-n)
73  */
74 struct pch_gpio_reg_data {
75 	u32 ien_reg;
76 	u32 imask_reg;
77 	u32 po_reg;
78 	u32 pm_reg;
79 	u32 im0_reg;
80 	u32 im1_reg;
81 	u32 gpio_use_sel_reg;
82 };
83 
84 /**
85  * struct pch_gpio - GPIO private data structure.
86  * @base:			PCI base address of Memory mapped I/O register.
87  * @reg:			Memory mapped PCH GPIO register list.
88  * @dev:			Pointer to device structure.
89  * @gpio:			Data for GPIO infrastructure.
90  * @pch_gpio_reg:		Memory mapped Register data is saved here
91  *				when suspend.
92  * @lock:			Used for register access protection
93  * @irq_base:		Save base of IRQ number for interrupt
94  * @ioh:		IOH ID
95  * @spinlock:		Used for register access protection
96  */
97 struct pch_gpio {
98 	void __iomem *base;
99 	struct pch_regs __iomem *reg;
100 	struct device *dev;
101 	struct gpio_chip gpio;
102 	struct pch_gpio_reg_data pch_gpio_reg;
103 	int irq_base;
104 	enum pch_type_t ioh;
105 	spinlock_t spinlock;
106 };
107 
108 static void pch_gpio_set(struct gpio_chip *gpio, unsigned nr, int val)
109 {
110 	u32 reg_val;
111 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
112 	unsigned long flags;
113 
114 	spin_lock_irqsave(&chip->spinlock, flags);
115 	reg_val = ioread32(&chip->reg->po);
116 	if (val)
117 		reg_val |= (1 << nr);
118 	else
119 		reg_val &= ~(1 << nr);
120 
121 	iowrite32(reg_val, &chip->reg->po);
122 	spin_unlock_irqrestore(&chip->spinlock, flags);
123 }
124 
125 static int pch_gpio_get(struct gpio_chip *gpio, unsigned nr)
126 {
127 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
128 
129 	return ioread32(&chip->reg->pi) & (1 << nr);
130 }
131 
132 static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
133 				     int val)
134 {
135 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
136 	u32 pm;
137 	u32 reg_val;
138 	unsigned long flags;
139 
140 	spin_lock_irqsave(&chip->spinlock, flags);
141 	pm = ioread32(&chip->reg->pm) & ((1 << gpio_pins[chip->ioh]) - 1);
142 	pm |= (1 << nr);
143 	iowrite32(pm, &chip->reg->pm);
144 
145 	reg_val = ioread32(&chip->reg->po);
146 	if (val)
147 		reg_val |= (1 << nr);
148 	else
149 		reg_val &= ~(1 << nr);
150 	iowrite32(reg_val, &chip->reg->po);
151 	spin_unlock_irqrestore(&chip->spinlock, flags);
152 
153 	return 0;
154 }
155 
156 static int pch_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
157 {
158 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
159 	u32 pm;
160 	unsigned long flags;
161 
162 	spin_lock_irqsave(&chip->spinlock, flags);
163 	pm = ioread32(&chip->reg->pm) & ((1 << gpio_pins[chip->ioh]) - 1);
164 	pm &= ~(1 << nr);
165 	iowrite32(pm, &chip->reg->pm);
166 	spin_unlock_irqrestore(&chip->spinlock, flags);
167 
168 	return 0;
169 }
170 
171 /*
172  * Save register configuration and disable interrupts.
173  */
174 static void pch_gpio_save_reg_conf(struct pch_gpio *chip)
175 {
176 	chip->pch_gpio_reg.ien_reg = ioread32(&chip->reg->ien);
177 	chip->pch_gpio_reg.imask_reg = ioread32(&chip->reg->imask);
178 	chip->pch_gpio_reg.po_reg = ioread32(&chip->reg->po);
179 	chip->pch_gpio_reg.pm_reg = ioread32(&chip->reg->pm);
180 	chip->pch_gpio_reg.im0_reg = ioread32(&chip->reg->im0);
181 	if (chip->ioh == INTEL_EG20T_PCH)
182 		chip->pch_gpio_reg.im1_reg = ioread32(&chip->reg->im1);
183 	if (chip->ioh == OKISEMI_ML7223n_IOH)
184 		chip->pch_gpio_reg.gpio_use_sel_reg =\
185 					    ioread32(&chip->reg->gpio_use_sel);
186 }
187 
188 /*
189  * This function restores the register configuration of the GPIO device.
190  */
191 static void pch_gpio_restore_reg_conf(struct pch_gpio *chip)
192 {
193 	iowrite32(chip->pch_gpio_reg.ien_reg, &chip->reg->ien);
194 	iowrite32(chip->pch_gpio_reg.imask_reg, &chip->reg->imask);
195 	/* to store contents of PO register */
196 	iowrite32(chip->pch_gpio_reg.po_reg, &chip->reg->po);
197 	/* to store contents of PM register */
198 	iowrite32(chip->pch_gpio_reg.pm_reg, &chip->reg->pm);
199 	iowrite32(chip->pch_gpio_reg.im0_reg, &chip->reg->im0);
200 	if (chip->ioh == INTEL_EG20T_PCH)
201 		iowrite32(chip->pch_gpio_reg.im1_reg, &chip->reg->im1);
202 	if (chip->ioh == OKISEMI_ML7223n_IOH)
203 		iowrite32(chip->pch_gpio_reg.gpio_use_sel_reg,
204 			  &chip->reg->gpio_use_sel);
205 }
206 
207 static int pch_gpio_to_irq(struct gpio_chip *gpio, unsigned offset)
208 {
209 	struct pch_gpio *chip = container_of(gpio, struct pch_gpio, gpio);
210 	return chip->irq_base + offset;
211 }
212 
213 static void pch_gpio_setup(struct pch_gpio *chip)
214 {
215 	struct gpio_chip *gpio = &chip->gpio;
216 
217 	gpio->label = dev_name(chip->dev);
218 	gpio->dev = chip->dev;
219 	gpio->owner = THIS_MODULE;
220 	gpio->direction_input = pch_gpio_direction_input;
221 	gpio->get = pch_gpio_get;
222 	gpio->direction_output = pch_gpio_direction_output;
223 	gpio->set = pch_gpio_set;
224 	gpio->dbg_show = NULL;
225 	gpio->base = -1;
226 	gpio->ngpio = gpio_pins[chip->ioh];
227 	gpio->can_sleep = 0;
228 	gpio->to_irq = pch_gpio_to_irq;
229 }
230 
231 static int pch_irq_type(struct irq_data *d, unsigned int type)
232 {
233 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
234 	struct pch_gpio *chip = gc->private;
235 	u32 im, im_pos, val;
236 	u32 __iomem *im_reg;
237 	unsigned long flags;
238 	int ch, irq = d->irq;
239 
240 	ch = irq - chip->irq_base;
241 	if (irq <= chip->irq_base + 7) {
242 		im_reg = &chip->reg->im0;
243 		im_pos = ch;
244 	} else {
245 		im_reg = &chip->reg->im1;
246 		im_pos = ch - 8;
247 	}
248 	dev_dbg(chip->dev, "%s:irq=%d type=%d ch=%d pos=%d\n",
249 		__func__, irq, type, ch, im_pos);
250 
251 	spin_lock_irqsave(&chip->spinlock, flags);
252 
253 	switch (type) {
254 	case IRQ_TYPE_EDGE_RISING:
255 		val = PCH_EDGE_RISING;
256 		break;
257 	case IRQ_TYPE_EDGE_FALLING:
258 		val = PCH_EDGE_FALLING;
259 		break;
260 	case IRQ_TYPE_EDGE_BOTH:
261 		val = PCH_EDGE_BOTH;
262 		break;
263 	case IRQ_TYPE_LEVEL_HIGH:
264 		val = PCH_LEVEL_H;
265 		break;
266 	case IRQ_TYPE_LEVEL_LOW:
267 		val = PCH_LEVEL_L;
268 		break;
269 	default:
270 		goto unlock;
271 	}
272 
273 	/* Set interrupt mode */
274 	im = ioread32(im_reg) & ~(PCH_IM_MASK << (im_pos * 4));
275 	iowrite32(im | (val << (im_pos * 4)), im_reg);
276 
277 	/* And the handler */
278 	if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
279 		__irq_set_handler_locked(d->irq, handle_level_irq);
280 	else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
281 		__irq_set_handler_locked(d->irq, handle_edge_irq);
282 
283 unlock:
284 	spin_unlock_irqrestore(&chip->spinlock, flags);
285 	return 0;
286 }
287 
288 static void pch_irq_unmask(struct irq_data *d)
289 {
290 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
291 	struct pch_gpio *chip = gc->private;
292 
293 	iowrite32(1 << (d->irq - chip->irq_base), &chip->reg->imaskclr);
294 }
295 
296 static void pch_irq_mask(struct irq_data *d)
297 {
298 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
299 	struct pch_gpio *chip = gc->private;
300 
301 	iowrite32(1 << (d->irq - chip->irq_base), &chip->reg->imask);
302 }
303 
304 static void pch_irq_ack(struct irq_data *d)
305 {
306 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
307 	struct pch_gpio *chip = gc->private;
308 
309 	iowrite32(1 << (d->irq - chip->irq_base), &chip->reg->iclr);
310 }
311 
312 static irqreturn_t pch_gpio_handler(int irq, void *dev_id)
313 {
314 	struct pch_gpio *chip = dev_id;
315 	u32 reg_val = ioread32(&chip->reg->istatus);
316 	int i, ret = IRQ_NONE;
317 
318 	for (i = 0; i < gpio_pins[chip->ioh]; i++) {
319 		if (reg_val & BIT(i)) {
320 			dev_dbg(chip->dev, "%s:[%d]:irq=%d  status=0x%x\n",
321 				__func__, i, irq, reg_val);
322 			generic_handle_irq(chip->irq_base + i);
323 			ret = IRQ_HANDLED;
324 		}
325 	}
326 	return ret;
327 }
328 
329 static void pch_gpio_alloc_generic_chip(struct pch_gpio *chip,
330 				unsigned int irq_start, unsigned int num)
331 {
332 	struct irq_chip_generic *gc;
333 	struct irq_chip_type *ct;
334 
335 	gc = irq_alloc_generic_chip("pch_gpio", 1, irq_start, chip->base,
336 				    handle_simple_irq);
337 	gc->private = chip;
338 	ct = gc->chip_types;
339 
340 	ct->chip.irq_ack = pch_irq_ack;
341 	ct->chip.irq_mask = pch_irq_mask;
342 	ct->chip.irq_unmask = pch_irq_unmask;
343 	ct->chip.irq_set_type = pch_irq_type;
344 
345 	irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
346 			       IRQ_NOREQUEST | IRQ_NOPROBE, 0);
347 }
348 
349 static int pch_gpio_probe(struct pci_dev *pdev,
350 				    const struct pci_device_id *id)
351 {
352 	s32 ret;
353 	struct pch_gpio *chip;
354 	int irq_base;
355 	u32 msk;
356 
357 	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
358 	if (chip == NULL)
359 		return -ENOMEM;
360 
361 	chip->dev = &pdev->dev;
362 	ret = pci_enable_device(pdev);
363 	if (ret) {
364 		dev_err(&pdev->dev, "%s : pci_enable_device FAILED", __func__);
365 		goto err_pci_enable;
366 	}
367 
368 	ret = pci_request_regions(pdev, KBUILD_MODNAME);
369 	if (ret) {
370 		dev_err(&pdev->dev, "pci_request_regions FAILED-%d", ret);
371 		goto err_request_regions;
372 	}
373 
374 	chip->base = pci_iomap(pdev, 1, 0);
375 	if (!chip->base) {
376 		dev_err(&pdev->dev, "%s : pci_iomap FAILED", __func__);
377 		ret = -ENOMEM;
378 		goto err_iomap;
379 	}
380 
381 	if (pdev->device == 0x8803)
382 		chip->ioh = INTEL_EG20T_PCH;
383 	else if (pdev->device == 0x8014)
384 		chip->ioh = OKISEMI_ML7223m_IOH;
385 	else if (pdev->device == 0x8043)
386 		chip->ioh = OKISEMI_ML7223n_IOH;
387 
388 	chip->reg = chip->base;
389 	pci_set_drvdata(pdev, chip);
390 	spin_lock_init(&chip->spinlock);
391 	pch_gpio_setup(chip);
392 	ret = gpiochip_add(&chip->gpio);
393 	if (ret) {
394 		dev_err(&pdev->dev, "PCH gpio: Failed to register GPIO\n");
395 		goto err_gpiochip_add;
396 	}
397 
398 	irq_base = irq_alloc_descs(-1, 0, gpio_pins[chip->ioh], NUMA_NO_NODE);
399 	if (irq_base < 0) {
400 		dev_warn(&pdev->dev, "PCH gpio: Failed to get IRQ base num\n");
401 		chip->irq_base = -1;
402 		goto end;
403 	}
404 	chip->irq_base = irq_base;
405 
406 	/* Mask all interrupts, but enable them */
407 	msk = (1 << gpio_pins[chip->ioh]) - 1;
408 	iowrite32(msk, &chip->reg->imask);
409 	iowrite32(msk, &chip->reg->ien);
410 
411 	ret = request_irq(pdev->irq, pch_gpio_handler,
412 			  IRQF_SHARED, KBUILD_MODNAME, chip);
413 	if (ret != 0) {
414 		dev_err(&pdev->dev,
415 			"%s request_irq failed\n", __func__);
416 		goto err_request_irq;
417 	}
418 
419 	pch_gpio_alloc_generic_chip(chip, irq_base, gpio_pins[chip->ioh]);
420 
421 end:
422 	return 0;
423 
424 err_request_irq:
425 	irq_free_descs(irq_base, gpio_pins[chip->ioh]);
426 
427 	if (gpiochip_remove(&chip->gpio))
428 		dev_err(&pdev->dev, "%s gpiochip_remove failed\n", __func__);
429 
430 err_gpiochip_add:
431 	pci_iounmap(pdev, chip->base);
432 
433 err_iomap:
434 	pci_release_regions(pdev);
435 
436 err_request_regions:
437 	pci_disable_device(pdev);
438 
439 err_pci_enable:
440 	kfree(chip);
441 	dev_err(&pdev->dev, "%s Failed returns %d\n", __func__, ret);
442 	return ret;
443 }
444 
445 static void pch_gpio_remove(struct pci_dev *pdev)
446 {
447 	int err;
448 	struct pch_gpio *chip = pci_get_drvdata(pdev);
449 
450 	if (chip->irq_base != -1) {
451 		free_irq(pdev->irq, chip);
452 
453 		irq_free_descs(chip->irq_base, gpio_pins[chip->ioh]);
454 	}
455 
456 	err = gpiochip_remove(&chip->gpio);
457 	if (err)
458 		dev_err(&pdev->dev, "Failed gpiochip_remove\n");
459 
460 	pci_iounmap(pdev, chip->base);
461 	pci_release_regions(pdev);
462 	pci_disable_device(pdev);
463 	kfree(chip);
464 }
465 
466 #ifdef CONFIG_PM
467 static int pch_gpio_suspend(struct pci_dev *pdev, pm_message_t state)
468 {
469 	s32 ret;
470 	struct pch_gpio *chip = pci_get_drvdata(pdev);
471 	unsigned long flags;
472 
473 	spin_lock_irqsave(&chip->spinlock, flags);
474 	pch_gpio_save_reg_conf(chip);
475 	spin_unlock_irqrestore(&chip->spinlock, flags);
476 
477 	ret = pci_save_state(pdev);
478 	if (ret) {
479 		dev_err(&pdev->dev, "pci_save_state Failed-%d\n", ret);
480 		return ret;
481 	}
482 	pci_disable_device(pdev);
483 	pci_set_power_state(pdev, PCI_D0);
484 	ret = pci_enable_wake(pdev, PCI_D0, 1);
485 	if (ret)
486 		dev_err(&pdev->dev, "pci_enable_wake Failed -%d\n", ret);
487 
488 	return 0;
489 }
490 
491 static int pch_gpio_resume(struct pci_dev *pdev)
492 {
493 	s32 ret;
494 	struct pch_gpio *chip = pci_get_drvdata(pdev);
495 	unsigned long flags;
496 
497 	ret = pci_enable_wake(pdev, PCI_D0, 0);
498 
499 	pci_set_power_state(pdev, PCI_D0);
500 	ret = pci_enable_device(pdev);
501 	if (ret) {
502 		dev_err(&pdev->dev, "pci_enable_device Failed-%d ", ret);
503 		return ret;
504 	}
505 	pci_restore_state(pdev);
506 
507 	spin_lock_irqsave(&chip->spinlock, flags);
508 	iowrite32(0x01, &chip->reg->reset);
509 	iowrite32(0x00, &chip->reg->reset);
510 	pch_gpio_restore_reg_conf(chip);
511 	spin_unlock_irqrestore(&chip->spinlock, flags);
512 
513 	return 0;
514 }
515 #else
516 #define pch_gpio_suspend NULL
517 #define pch_gpio_resume NULL
518 #endif
519 
520 #define PCI_VENDOR_ID_ROHM             0x10DB
521 static DEFINE_PCI_DEVICE_TABLE(pch_gpio_pcidev_id) = {
522 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8803) },
523 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8014) },
524 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8043) },
525 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8803) },
526 	{ 0, }
527 };
528 MODULE_DEVICE_TABLE(pci, pch_gpio_pcidev_id);
529 
530 static struct pci_driver pch_gpio_driver = {
531 	.name = "pch_gpio",
532 	.id_table = pch_gpio_pcidev_id,
533 	.probe = pch_gpio_probe,
534 	.remove = pch_gpio_remove,
535 	.suspend = pch_gpio_suspend,
536 	.resume = pch_gpio_resume
537 };
538 
539 module_pci_driver(pch_gpio_driver);
540 
541 MODULE_DESCRIPTION("PCH GPIO PCI Driver");
542 MODULE_LICENSE("GPL");
543