xref: /linux/drivers/gpio/gpio-pch.c (revision f8e17c17b81070f38062dce79ca7f4541851dadd)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
4  */
5 #include <linux/gpio/driver.h>
6 #include <linux/interrupt.h>
7 #include <linux/irq.h>
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/pci.h>
11 #include <linux/slab.h>
12 
13 #define PCH_EDGE_FALLING	0
14 #define PCH_EDGE_RISING		BIT(0)
15 #define PCH_LEVEL_L		BIT(1)
16 #define PCH_LEVEL_H		(BIT(0) | BIT(1))
17 #define PCH_EDGE_BOTH		BIT(2)
18 #define PCH_IM_MASK		(BIT(0) | BIT(1) | BIT(2))
19 
20 #define PCH_IRQ_BASE		24
21 
22 struct pch_regs {
23 	u32	ien;
24 	u32	istatus;
25 	u32	idisp;
26 	u32	iclr;
27 	u32	imask;
28 	u32	imaskclr;
29 	u32	po;
30 	u32	pi;
31 	u32	pm;
32 	u32	im0;
33 	u32	im1;
34 	u32	reserved[3];
35 	u32	gpio_use_sel;
36 	u32	reset;
37 };
38 
39 enum pch_type_t {
40 	INTEL_EG20T_PCH,
41 	OKISEMI_ML7223m_IOH, /* LAPIS Semiconductor ML7223 IOH PCIe Bus-m */
42 	OKISEMI_ML7223n_IOH  /* LAPIS Semiconductor ML7223 IOH PCIe Bus-n */
43 };
44 
45 /* Specifies number of GPIO PINS */
46 static int gpio_pins[] = {
47 	[INTEL_EG20T_PCH] = 12,
48 	[OKISEMI_ML7223m_IOH] = 8,
49 	[OKISEMI_ML7223n_IOH] = 8,
50 };
51 
52 /**
53  * struct pch_gpio_reg_data - The register store data.
54  * @ien_reg:	To store contents of IEN register.
55  * @imask_reg:	To store contents of IMASK register.
56  * @po_reg:	To store contents of PO register.
57  * @pm_reg:	To store contents of PM register.
58  * @im0_reg:	To store contents of IM0 register.
59  * @im1_reg:	To store contents of IM1 register.
60  * @gpio_use_sel_reg : To store contents of GPIO_USE_SEL register.
61  *		       (Only ML7223 Bus-n)
62  */
63 struct pch_gpio_reg_data {
64 	u32 ien_reg;
65 	u32 imask_reg;
66 	u32 po_reg;
67 	u32 pm_reg;
68 	u32 im0_reg;
69 	u32 im1_reg;
70 	u32 gpio_use_sel_reg;
71 };
72 
73 /**
74  * struct pch_gpio - GPIO private data structure.
75  * @base:			PCI base address of Memory mapped I/O register.
76  * @reg:			Memory mapped PCH GPIO register list.
77  * @dev:			Pointer to device structure.
78  * @gpio:			Data for GPIO infrastructure.
79  * @pch_gpio_reg:		Memory mapped Register data is saved here
80  *				when suspend.
81  * @lock:			Used for register access protection
82  * @irq_base:		Save base of IRQ number for interrupt
83  * @ioh:		IOH ID
84  * @spinlock:		Used for register access protection
85  */
86 struct pch_gpio {
87 	void __iomem *base;
88 	struct pch_regs __iomem *reg;
89 	struct device *dev;
90 	struct gpio_chip gpio;
91 	struct pch_gpio_reg_data pch_gpio_reg;
92 	int irq_base;
93 	enum pch_type_t ioh;
94 	spinlock_t spinlock;
95 };
96 
97 static void pch_gpio_set(struct gpio_chip *gpio, unsigned nr, int val)
98 {
99 	u32 reg_val;
100 	struct pch_gpio *chip =	gpiochip_get_data(gpio);
101 	unsigned long flags;
102 
103 	spin_lock_irqsave(&chip->spinlock, flags);
104 	reg_val = ioread32(&chip->reg->po);
105 	if (val)
106 		reg_val |= (1 << nr);
107 	else
108 		reg_val &= ~(1 << nr);
109 
110 	iowrite32(reg_val, &chip->reg->po);
111 	spin_unlock_irqrestore(&chip->spinlock, flags);
112 }
113 
114 static int pch_gpio_get(struct gpio_chip *gpio, unsigned nr)
115 {
116 	struct pch_gpio *chip =	gpiochip_get_data(gpio);
117 
118 	return (ioread32(&chip->reg->pi) >> nr) & 1;
119 }
120 
121 static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
122 				     int val)
123 {
124 	struct pch_gpio *chip =	gpiochip_get_data(gpio);
125 	u32 pm;
126 	u32 reg_val;
127 	unsigned long flags;
128 
129 	spin_lock_irqsave(&chip->spinlock, flags);
130 
131 	reg_val = ioread32(&chip->reg->po);
132 	if (val)
133 		reg_val |= (1 << nr);
134 	else
135 		reg_val &= ~(1 << nr);
136 	iowrite32(reg_val, &chip->reg->po);
137 
138 	pm = ioread32(&chip->reg->pm) & ((1 << gpio_pins[chip->ioh]) - 1);
139 	pm |= (1 << nr);
140 	iowrite32(pm, &chip->reg->pm);
141 
142 	spin_unlock_irqrestore(&chip->spinlock, flags);
143 
144 	return 0;
145 }
146 
147 static int pch_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
148 {
149 	struct pch_gpio *chip =	gpiochip_get_data(gpio);
150 	u32 pm;
151 	unsigned long flags;
152 
153 	spin_lock_irqsave(&chip->spinlock, flags);
154 	pm = ioread32(&chip->reg->pm) & ((1 << gpio_pins[chip->ioh]) - 1);
155 	pm &= ~(1 << nr);
156 	iowrite32(pm, &chip->reg->pm);
157 	spin_unlock_irqrestore(&chip->spinlock, flags);
158 
159 	return 0;
160 }
161 
162 /*
163  * Save register configuration and disable interrupts.
164  */
165 static void __maybe_unused pch_gpio_save_reg_conf(struct pch_gpio *chip)
166 {
167 	chip->pch_gpio_reg.ien_reg = ioread32(&chip->reg->ien);
168 	chip->pch_gpio_reg.imask_reg = ioread32(&chip->reg->imask);
169 	chip->pch_gpio_reg.po_reg = ioread32(&chip->reg->po);
170 	chip->pch_gpio_reg.pm_reg = ioread32(&chip->reg->pm);
171 	chip->pch_gpio_reg.im0_reg = ioread32(&chip->reg->im0);
172 	if (chip->ioh == INTEL_EG20T_PCH)
173 		chip->pch_gpio_reg.im1_reg = ioread32(&chip->reg->im1);
174 	if (chip->ioh == OKISEMI_ML7223n_IOH)
175 		chip->pch_gpio_reg.gpio_use_sel_reg = ioread32(&chip->reg->gpio_use_sel);
176 }
177 
178 /*
179  * This function restores the register configuration of the GPIO device.
180  */
181 static void __maybe_unused pch_gpio_restore_reg_conf(struct pch_gpio *chip)
182 {
183 	iowrite32(chip->pch_gpio_reg.ien_reg, &chip->reg->ien);
184 	iowrite32(chip->pch_gpio_reg.imask_reg, &chip->reg->imask);
185 	/* to store contents of PO register */
186 	iowrite32(chip->pch_gpio_reg.po_reg, &chip->reg->po);
187 	/* to store contents of PM register */
188 	iowrite32(chip->pch_gpio_reg.pm_reg, &chip->reg->pm);
189 	iowrite32(chip->pch_gpio_reg.im0_reg, &chip->reg->im0);
190 	if (chip->ioh == INTEL_EG20T_PCH)
191 		iowrite32(chip->pch_gpio_reg.im1_reg, &chip->reg->im1);
192 	if (chip->ioh == OKISEMI_ML7223n_IOH)
193 		iowrite32(chip->pch_gpio_reg.gpio_use_sel_reg, &chip->reg->gpio_use_sel);
194 }
195 
196 static int pch_gpio_to_irq(struct gpio_chip *gpio, unsigned offset)
197 {
198 	struct pch_gpio *chip = gpiochip_get_data(gpio);
199 	return chip->irq_base + offset;
200 }
201 
202 static void pch_gpio_setup(struct pch_gpio *chip)
203 {
204 	struct gpio_chip *gpio = &chip->gpio;
205 
206 	gpio->label = dev_name(chip->dev);
207 	gpio->parent = chip->dev;
208 	gpio->owner = THIS_MODULE;
209 	gpio->direction_input = pch_gpio_direction_input;
210 	gpio->get = pch_gpio_get;
211 	gpio->direction_output = pch_gpio_direction_output;
212 	gpio->set = pch_gpio_set;
213 	gpio->base = -1;
214 	gpio->ngpio = gpio_pins[chip->ioh];
215 	gpio->can_sleep = false;
216 	gpio->to_irq = pch_gpio_to_irq;
217 }
218 
219 static int pch_irq_type(struct irq_data *d, unsigned int type)
220 {
221 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
222 	struct pch_gpio *chip = gc->private;
223 	u32 im, im_pos, val;
224 	u32 __iomem *im_reg;
225 	unsigned long flags;
226 	int ch, irq = d->irq;
227 
228 	ch = irq - chip->irq_base;
229 	if (irq <= chip->irq_base + 7) {
230 		im_reg = &chip->reg->im0;
231 		im_pos = ch;
232 	} else {
233 		im_reg = &chip->reg->im1;
234 		im_pos = ch - 8;
235 	}
236 	dev_dbg(chip->dev, "irq=%d type=%d ch=%d pos=%d\n", irq, type, ch, im_pos);
237 
238 	spin_lock_irqsave(&chip->spinlock, flags);
239 
240 	switch (type) {
241 	case IRQ_TYPE_EDGE_RISING:
242 		val = PCH_EDGE_RISING;
243 		break;
244 	case IRQ_TYPE_EDGE_FALLING:
245 		val = PCH_EDGE_FALLING;
246 		break;
247 	case IRQ_TYPE_EDGE_BOTH:
248 		val = PCH_EDGE_BOTH;
249 		break;
250 	case IRQ_TYPE_LEVEL_HIGH:
251 		val = PCH_LEVEL_H;
252 		break;
253 	case IRQ_TYPE_LEVEL_LOW:
254 		val = PCH_LEVEL_L;
255 		break;
256 	default:
257 		goto unlock;
258 	}
259 
260 	/* Set interrupt mode */
261 	im = ioread32(im_reg) & ~(PCH_IM_MASK << (im_pos * 4));
262 	iowrite32(im | (val << (im_pos * 4)), im_reg);
263 
264 	/* And the handler */
265 	if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
266 		irq_set_handler_locked(d, handle_level_irq);
267 	else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
268 		irq_set_handler_locked(d, handle_edge_irq);
269 
270 unlock:
271 	spin_unlock_irqrestore(&chip->spinlock, flags);
272 	return 0;
273 }
274 
275 static void pch_irq_unmask(struct irq_data *d)
276 {
277 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
278 	struct pch_gpio *chip = gc->private;
279 
280 	iowrite32(1 << (d->irq - chip->irq_base), &chip->reg->imaskclr);
281 }
282 
283 static void pch_irq_mask(struct irq_data *d)
284 {
285 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
286 	struct pch_gpio *chip = gc->private;
287 
288 	iowrite32(1 << (d->irq - chip->irq_base), &chip->reg->imask);
289 }
290 
291 static void pch_irq_ack(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->iclr);
297 }
298 
299 static irqreturn_t pch_gpio_handler(int irq, void *dev_id)
300 {
301 	struct pch_gpio *chip = dev_id;
302 	unsigned long reg_val = ioread32(&chip->reg->istatus);
303 	int i, ret = IRQ_NONE;
304 
305 	for_each_set_bit(i, &reg_val, gpio_pins[chip->ioh]) {
306 		dev_dbg(chip->dev, "[%d]:irq=%d  status=0x%lx\n", i, irq, reg_val);
307 		generic_handle_irq(chip->irq_base + i);
308 		ret = IRQ_HANDLED;
309 	}
310 	return ret;
311 }
312 
313 static int pch_gpio_alloc_generic_chip(struct pch_gpio *chip,
314 				       unsigned int irq_start,
315 				       unsigned int num)
316 {
317 	struct irq_chip_generic *gc;
318 	struct irq_chip_type *ct;
319 	int rv;
320 
321 	gc = devm_irq_alloc_generic_chip(chip->dev, "pch_gpio", 1, irq_start,
322 					 chip->base, handle_simple_irq);
323 	if (!gc)
324 		return -ENOMEM;
325 
326 	gc->private = chip;
327 	ct = gc->chip_types;
328 
329 	ct->chip.irq_ack = pch_irq_ack;
330 	ct->chip.irq_mask = pch_irq_mask;
331 	ct->chip.irq_unmask = pch_irq_unmask;
332 	ct->chip.irq_set_type = pch_irq_type;
333 
334 	rv = devm_irq_setup_generic_chip(chip->dev, gc, IRQ_MSK(num),
335 					 IRQ_GC_INIT_MASK_CACHE,
336 					 IRQ_NOREQUEST | IRQ_NOPROBE, 0);
337 
338 	return rv;
339 }
340 
341 static int pch_gpio_probe(struct pci_dev *pdev,
342 				    const struct pci_device_id *id)
343 {
344 	s32 ret;
345 	struct pch_gpio *chip;
346 	int irq_base;
347 	u32 msk;
348 
349 	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
350 	if (chip == NULL)
351 		return -ENOMEM;
352 
353 	chip->dev = &pdev->dev;
354 	ret = pcim_enable_device(pdev);
355 	if (ret) {
356 		dev_err(&pdev->dev, "pci_enable_device FAILED");
357 		return ret;
358 	}
359 
360 	ret = pcim_iomap_regions(pdev, 1 << 1, KBUILD_MODNAME);
361 	if (ret) {
362 		dev_err(&pdev->dev, "pci_request_regions FAILED-%d", ret);
363 		return ret;
364 	}
365 
366 	chip->base = pcim_iomap_table(pdev)[1];
367 
368 	if (pdev->device == 0x8803)
369 		chip->ioh = INTEL_EG20T_PCH;
370 	else if (pdev->device == 0x8014)
371 		chip->ioh = OKISEMI_ML7223m_IOH;
372 	else if (pdev->device == 0x8043)
373 		chip->ioh = OKISEMI_ML7223n_IOH;
374 
375 	chip->reg = chip->base;
376 	pci_set_drvdata(pdev, chip);
377 	spin_lock_init(&chip->spinlock);
378 	pch_gpio_setup(chip);
379 
380 	ret = devm_gpiochip_add_data(&pdev->dev, &chip->gpio, chip);
381 	if (ret) {
382 		dev_err(&pdev->dev, "PCH gpio: Failed to register GPIO\n");
383 		return ret;
384 	}
385 
386 	irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0,
387 					gpio_pins[chip->ioh], NUMA_NO_NODE);
388 	if (irq_base < 0) {
389 		dev_warn(&pdev->dev, "PCH gpio: Failed to get IRQ base num\n");
390 		chip->irq_base = -1;
391 		return 0;
392 	}
393 	chip->irq_base = irq_base;
394 
395 	/* Mask all interrupts, but enable them */
396 	msk = (1 << gpio_pins[chip->ioh]) - 1;
397 	iowrite32(msk, &chip->reg->imask);
398 	iowrite32(msk, &chip->reg->ien);
399 
400 	ret = devm_request_irq(&pdev->dev, pdev->irq, pch_gpio_handler,
401 			       IRQF_SHARED, KBUILD_MODNAME, chip);
402 	if (ret) {
403 		dev_err(&pdev->dev, "request_irq failed\n");
404 		return ret;
405 	}
406 
407 	return pch_gpio_alloc_generic_chip(chip, irq_base, gpio_pins[chip->ioh]);
408 }
409 
410 static int __maybe_unused pch_gpio_suspend(struct device *dev)
411 {
412 	struct pch_gpio *chip = dev_get_drvdata(dev);
413 	unsigned long flags;
414 
415 	spin_lock_irqsave(&chip->spinlock, flags);
416 	pch_gpio_save_reg_conf(chip);
417 	spin_unlock_irqrestore(&chip->spinlock, flags);
418 
419 	return 0;
420 }
421 
422 static int __maybe_unused pch_gpio_resume(struct device *dev)
423 {
424 	struct pch_gpio *chip = dev_get_drvdata(dev);
425 	unsigned long flags;
426 
427 	spin_lock_irqsave(&chip->spinlock, flags);
428 	iowrite32(0x01, &chip->reg->reset);
429 	iowrite32(0x00, &chip->reg->reset);
430 	pch_gpio_restore_reg_conf(chip);
431 	spin_unlock_irqrestore(&chip->spinlock, flags);
432 
433 	return 0;
434 }
435 
436 static SIMPLE_DEV_PM_OPS(pch_gpio_pm_ops, pch_gpio_suspend, pch_gpio_resume);
437 
438 static const struct pci_device_id pch_gpio_pcidev_id[] = {
439 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8803) },
440 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8014) },
441 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8043) },
442 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8803) },
443 	{ 0, }
444 };
445 MODULE_DEVICE_TABLE(pci, pch_gpio_pcidev_id);
446 
447 static struct pci_driver pch_gpio_driver = {
448 	.name = "pch_gpio",
449 	.id_table = pch_gpio_pcidev_id,
450 	.probe = pch_gpio_probe,
451 	.driver = {
452 		.pm = &pch_gpio_pm_ops,
453 	},
454 };
455 
456 module_pci_driver(pch_gpio_driver);
457 
458 MODULE_DESCRIPTION("PCH GPIO PCI Driver");
459 MODULE_LICENSE("GPL v2");
460