xref: /openbmc/linux/drivers/gpio/gpio-pch.c (revision f71a261a)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
4  */
5 #include <linux/bits.h>
6 #include <linux/gpio/driver.h>
7 #include <linux/interrupt.h>
8 #include <linux/irq.h>
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/pci.h>
12 #include <linux/slab.h>
13 
14 #define PCH_EDGE_FALLING	0
15 #define PCH_EDGE_RISING		1
16 #define PCH_LEVEL_L		2
17 #define PCH_LEVEL_H		3
18 #define PCH_EDGE_BOTH		4
19 #define PCH_IM_MASK		GENMASK(2, 0)
20 
21 #define PCH_IRQ_BASE		24
22 
23 struct pch_regs {
24 	u32	ien;
25 	u32	istatus;
26 	u32	idisp;
27 	u32	iclr;
28 	u32	imask;
29 	u32	imaskclr;
30 	u32	po;
31 	u32	pi;
32 	u32	pm;
33 	u32	im0;
34 	u32	im1;
35 	u32	reserved[3];
36 	u32	gpio_use_sel;
37 	u32	reset;
38 };
39 
40 enum pch_type_t {
41 	INTEL_EG20T_PCH,
42 	OKISEMI_ML7223m_IOH, /* LAPIS Semiconductor ML7223 IOH PCIe Bus-m */
43 	OKISEMI_ML7223n_IOH  /* LAPIS Semiconductor ML7223 IOH PCIe Bus-n */
44 };
45 
46 /* Specifies number of GPIO PINS */
47 static int gpio_pins[] = {
48 	[INTEL_EG20T_PCH] = 12,
49 	[OKISEMI_ML7223m_IOH] = 8,
50 	[OKISEMI_ML7223n_IOH] = 8,
51 };
52 
53 /**
54  * struct pch_gpio_reg_data - The register store data.
55  * @ien_reg:	To store contents of IEN register.
56  * @imask_reg:	To store contents of IMASK register.
57  * @po_reg:	To store contents of PO register.
58  * @pm_reg:	To store contents of PM register.
59  * @im0_reg:	To store contents of IM0 register.
60  * @im1_reg:	To store contents of IM1 register.
61  * @gpio_use_sel_reg : To store contents of GPIO_USE_SEL register.
62  *		       (Only ML7223 Bus-n)
63  */
64 struct pch_gpio_reg_data {
65 	u32 ien_reg;
66 	u32 imask_reg;
67 	u32 po_reg;
68 	u32 pm_reg;
69 	u32 im0_reg;
70 	u32 im1_reg;
71 	u32 gpio_use_sel_reg;
72 };
73 
74 /**
75  * struct pch_gpio - GPIO private data structure.
76  * @base:			PCI base address of Memory mapped I/O register.
77  * @reg:			Memory mapped PCH GPIO register list.
78  * @dev:			Pointer to device structure.
79  * @gpio:			Data for GPIO infrastructure.
80  * @pch_gpio_reg:		Memory mapped Register data is saved here
81  *				when suspend.
82  * @lock:			Used for register access protection
83  * @irq_base:		Save base of IRQ number for interrupt
84  * @ioh:		IOH ID
85  * @spinlock:		Used for register access protection
86  */
87 struct pch_gpio {
88 	void __iomem *base;
89 	struct pch_regs __iomem *reg;
90 	struct device *dev;
91 	struct gpio_chip gpio;
92 	struct pch_gpio_reg_data pch_gpio_reg;
93 	int irq_base;
94 	enum pch_type_t ioh;
95 	spinlock_t spinlock;
96 };
97 
98 static void pch_gpio_set(struct gpio_chip *gpio, unsigned int nr, int val)
99 {
100 	u32 reg_val;
101 	struct pch_gpio *chip =	gpiochip_get_data(gpio);
102 	unsigned long flags;
103 
104 	spin_lock_irqsave(&chip->spinlock, flags);
105 	reg_val = ioread32(&chip->reg->po);
106 	if (val)
107 		reg_val |= BIT(nr);
108 	else
109 		reg_val &= ~BIT(nr);
110 
111 	iowrite32(reg_val, &chip->reg->po);
112 	spin_unlock_irqrestore(&chip->spinlock, flags);
113 }
114 
115 static int pch_gpio_get(struct gpio_chip *gpio, unsigned int nr)
116 {
117 	struct pch_gpio *chip =	gpiochip_get_data(gpio);
118 
119 	return !!(ioread32(&chip->reg->pi) & BIT(nr));
120 }
121 
122 static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned int nr,
123 				     int val)
124 {
125 	struct pch_gpio *chip =	gpiochip_get_data(gpio);
126 	u32 pm;
127 	u32 reg_val;
128 	unsigned long flags;
129 
130 	spin_lock_irqsave(&chip->spinlock, flags);
131 
132 	reg_val = ioread32(&chip->reg->po);
133 	if (val)
134 		reg_val |= BIT(nr);
135 	else
136 		reg_val &= ~BIT(nr);
137 	iowrite32(reg_val, &chip->reg->po);
138 
139 	pm = ioread32(&chip->reg->pm);
140 	pm &= BIT(gpio_pins[chip->ioh]) - 1;
141 	pm |= BIT(nr);
142 	iowrite32(pm, &chip->reg->pm);
143 
144 	spin_unlock_irqrestore(&chip->spinlock, flags);
145 
146 	return 0;
147 }
148 
149 static int pch_gpio_direction_input(struct gpio_chip *gpio, unsigned int nr)
150 {
151 	struct pch_gpio *chip =	gpiochip_get_data(gpio);
152 	u32 pm;
153 	unsigned long flags;
154 
155 	spin_lock_irqsave(&chip->spinlock, flags);
156 	pm = ioread32(&chip->reg->pm);
157 	pm &= BIT(gpio_pins[chip->ioh]) - 1;
158 	pm &= ~BIT(nr);
159 	iowrite32(pm, &chip->reg->pm);
160 	spin_unlock_irqrestore(&chip->spinlock, flags);
161 
162 	return 0;
163 }
164 
165 /*
166  * Save register configuration and disable interrupts.
167  */
168 static void __maybe_unused pch_gpio_save_reg_conf(struct pch_gpio *chip)
169 {
170 	chip->pch_gpio_reg.ien_reg = ioread32(&chip->reg->ien);
171 	chip->pch_gpio_reg.imask_reg = ioread32(&chip->reg->imask);
172 	chip->pch_gpio_reg.po_reg = ioread32(&chip->reg->po);
173 	chip->pch_gpio_reg.pm_reg = ioread32(&chip->reg->pm);
174 	chip->pch_gpio_reg.im0_reg = ioread32(&chip->reg->im0);
175 	if (chip->ioh == INTEL_EG20T_PCH)
176 		chip->pch_gpio_reg.im1_reg = ioread32(&chip->reg->im1);
177 	if (chip->ioh == OKISEMI_ML7223n_IOH)
178 		chip->pch_gpio_reg.gpio_use_sel_reg = ioread32(&chip->reg->gpio_use_sel);
179 }
180 
181 /*
182  * This function restores the register configuration of the GPIO device.
183  */
184 static void __maybe_unused pch_gpio_restore_reg_conf(struct pch_gpio *chip)
185 {
186 	iowrite32(chip->pch_gpio_reg.ien_reg, &chip->reg->ien);
187 	iowrite32(chip->pch_gpio_reg.imask_reg, &chip->reg->imask);
188 	/* to store contents of PO register */
189 	iowrite32(chip->pch_gpio_reg.po_reg, &chip->reg->po);
190 	/* to store contents of PM register */
191 	iowrite32(chip->pch_gpio_reg.pm_reg, &chip->reg->pm);
192 	iowrite32(chip->pch_gpio_reg.im0_reg, &chip->reg->im0);
193 	if (chip->ioh == INTEL_EG20T_PCH)
194 		iowrite32(chip->pch_gpio_reg.im1_reg, &chip->reg->im1);
195 	if (chip->ioh == OKISEMI_ML7223n_IOH)
196 		iowrite32(chip->pch_gpio_reg.gpio_use_sel_reg, &chip->reg->gpio_use_sel);
197 }
198 
199 static int pch_gpio_to_irq(struct gpio_chip *gpio, unsigned int offset)
200 {
201 	struct pch_gpio *chip = gpiochip_get_data(gpio);
202 
203 	return chip->irq_base + offset;
204 }
205 
206 static void pch_gpio_setup(struct pch_gpio *chip)
207 {
208 	struct gpio_chip *gpio = &chip->gpio;
209 
210 	gpio->label = dev_name(chip->dev);
211 	gpio->parent = chip->dev;
212 	gpio->owner = THIS_MODULE;
213 	gpio->direction_input = pch_gpio_direction_input;
214 	gpio->get = pch_gpio_get;
215 	gpio->direction_output = pch_gpio_direction_output;
216 	gpio->set = pch_gpio_set;
217 	gpio->base = -1;
218 	gpio->ngpio = gpio_pins[chip->ioh];
219 	gpio->can_sleep = false;
220 	gpio->to_irq = pch_gpio_to_irq;
221 }
222 
223 static int pch_irq_type(struct irq_data *d, unsigned int type)
224 {
225 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
226 	struct pch_gpio *chip = gc->private;
227 	u32 im, im_pos, val;
228 	u32 __iomem *im_reg;
229 	unsigned long flags;
230 	int ch, irq = d->irq;
231 
232 	ch = irq - chip->irq_base;
233 	if (irq < chip->irq_base + 8) {
234 		im_reg = &chip->reg->im0;
235 		im_pos = ch - 0;
236 	} else {
237 		im_reg = &chip->reg->im1;
238 		im_pos = ch - 8;
239 	}
240 	dev_dbg(chip->dev, "irq=%d type=%d ch=%d pos=%d\n", irq, type, ch, im_pos);
241 
242 	switch (type) {
243 	case IRQ_TYPE_EDGE_RISING:
244 		val = PCH_EDGE_RISING;
245 		break;
246 	case IRQ_TYPE_EDGE_FALLING:
247 		val = PCH_EDGE_FALLING;
248 		break;
249 	case IRQ_TYPE_EDGE_BOTH:
250 		val = PCH_EDGE_BOTH;
251 		break;
252 	case IRQ_TYPE_LEVEL_HIGH:
253 		val = PCH_LEVEL_H;
254 		break;
255 	case IRQ_TYPE_LEVEL_LOW:
256 		val = PCH_LEVEL_L;
257 		break;
258 	default:
259 		return 0;
260 	}
261 
262 	spin_lock_irqsave(&chip->spinlock, flags);
263 
264 	/* Set interrupt mode */
265 	im = ioread32(im_reg) & ~(PCH_IM_MASK << (im_pos * 4));
266 	iowrite32(im | (val << (im_pos * 4)), im_reg);
267 
268 	/* And the handler */
269 	if (type & IRQ_TYPE_LEVEL_MASK)
270 		irq_set_handler_locked(d, handle_level_irq);
271 	else if (type & IRQ_TYPE_EDGE_BOTH)
272 		irq_set_handler_locked(d, handle_edge_irq);
273 
274 	spin_unlock_irqrestore(&chip->spinlock, flags);
275 	return 0;
276 }
277 
278 static void pch_irq_unmask(struct irq_data *d)
279 {
280 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
281 	struct pch_gpio *chip = gc->private;
282 
283 	iowrite32(BIT(d->irq - chip->irq_base), &chip->reg->imaskclr);
284 }
285 
286 static void pch_irq_mask(struct irq_data *d)
287 {
288 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
289 	struct pch_gpio *chip = gc->private;
290 
291 	iowrite32(BIT(d->irq - chip->irq_base), &chip->reg->imask);
292 }
293 
294 static void pch_irq_ack(struct irq_data *d)
295 {
296 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
297 	struct pch_gpio *chip = gc->private;
298 
299 	iowrite32(BIT(d->irq - chip->irq_base), &chip->reg->iclr);
300 }
301 
302 static irqreturn_t pch_gpio_handler(int irq, void *dev_id)
303 {
304 	struct pch_gpio *chip = dev_id;
305 	unsigned long reg_val = ioread32(&chip->reg->istatus);
306 	int i;
307 
308 	dev_vdbg(chip->dev, "irq=%d  status=0x%lx\n", irq, reg_val);
309 
310 	reg_val &= BIT(gpio_pins[chip->ioh]) - 1;
311 
312 	for_each_set_bit(i, &reg_val, gpio_pins[chip->ioh])
313 		generic_handle_irq(chip->irq_base + i);
314 
315 	return IRQ_RETVAL(reg_val);
316 }
317 
318 static int pch_gpio_alloc_generic_chip(struct pch_gpio *chip,
319 				       unsigned int irq_start,
320 				       unsigned int num)
321 {
322 	struct irq_chip_generic *gc;
323 	struct irq_chip_type *ct;
324 	int rv;
325 
326 	gc = devm_irq_alloc_generic_chip(chip->dev, "pch_gpio", 1, irq_start,
327 					 chip->base, handle_simple_irq);
328 	if (!gc)
329 		return -ENOMEM;
330 
331 	gc->private = chip;
332 	ct = gc->chip_types;
333 
334 	ct->chip.irq_ack = pch_irq_ack;
335 	ct->chip.irq_mask = pch_irq_mask;
336 	ct->chip.irq_unmask = pch_irq_unmask;
337 	ct->chip.irq_set_type = pch_irq_type;
338 
339 	rv = devm_irq_setup_generic_chip(chip->dev, gc, IRQ_MSK(num),
340 					 IRQ_GC_INIT_MASK_CACHE,
341 					 IRQ_NOREQUEST | IRQ_NOPROBE, 0);
342 
343 	return rv;
344 }
345 
346 static int pch_gpio_probe(struct pci_dev *pdev,
347 				    const struct pci_device_id *id)
348 {
349 	struct device *dev = &pdev->dev;
350 	s32 ret;
351 	struct pch_gpio *chip;
352 	int irq_base;
353 
354 	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
355 	if (chip == NULL)
356 		return -ENOMEM;
357 
358 	chip->dev = dev;
359 	ret = pcim_enable_device(pdev);
360 	if (ret) {
361 		dev_err(dev, "pci_enable_device FAILED");
362 		return ret;
363 	}
364 
365 	ret = pcim_iomap_regions(pdev, BIT(1), KBUILD_MODNAME);
366 	if (ret) {
367 		dev_err(dev, "pci_request_regions FAILED-%d", ret);
368 		return ret;
369 	}
370 
371 	chip->base = pcim_iomap_table(pdev)[1];
372 	chip->ioh = id->driver_data;
373 	chip->reg = chip->base;
374 	pci_set_drvdata(pdev, chip);
375 	spin_lock_init(&chip->spinlock);
376 	pch_gpio_setup(chip);
377 
378 	ret = devm_gpiochip_add_data(dev, &chip->gpio, chip);
379 	if (ret) {
380 		dev_err(dev, "PCH gpio: Failed to register GPIO\n");
381 		return ret;
382 	}
383 
384 	irq_base = devm_irq_alloc_descs(dev, -1, 0,
385 					gpio_pins[chip->ioh], NUMA_NO_NODE);
386 	if (irq_base < 0) {
387 		dev_warn(dev, "PCH gpio: Failed to get IRQ base num\n");
388 		chip->irq_base = -1;
389 		return 0;
390 	}
391 	chip->irq_base = irq_base;
392 
393 	/* Mask all interrupts, but enable them */
394 	iowrite32(BIT(gpio_pins[chip->ioh]) - 1, &chip->reg->imask);
395 	iowrite32(BIT(gpio_pins[chip->ioh]) - 1, &chip->reg->ien);
396 
397 	ret = devm_request_irq(dev, pdev->irq, pch_gpio_handler,
398 			       IRQF_SHARED, KBUILD_MODNAME, chip);
399 	if (ret) {
400 		dev_err(dev, "request_irq failed\n");
401 		return ret;
402 	}
403 
404 	return pch_gpio_alloc_generic_chip(chip, irq_base, gpio_pins[chip->ioh]);
405 }
406 
407 static int __maybe_unused pch_gpio_suspend(struct device *dev)
408 {
409 	struct pch_gpio *chip = dev_get_drvdata(dev);
410 	unsigned long flags;
411 
412 	spin_lock_irqsave(&chip->spinlock, flags);
413 	pch_gpio_save_reg_conf(chip);
414 	spin_unlock_irqrestore(&chip->spinlock, flags);
415 
416 	return 0;
417 }
418 
419 static int __maybe_unused pch_gpio_resume(struct device *dev)
420 {
421 	struct pch_gpio *chip = dev_get_drvdata(dev);
422 	unsigned long flags;
423 
424 	spin_lock_irqsave(&chip->spinlock, flags);
425 	iowrite32(0x01, &chip->reg->reset);
426 	iowrite32(0x00, &chip->reg->reset);
427 	pch_gpio_restore_reg_conf(chip);
428 	spin_unlock_irqrestore(&chip->spinlock, flags);
429 
430 	return 0;
431 }
432 
433 static SIMPLE_DEV_PM_OPS(pch_gpio_pm_ops, pch_gpio_suspend, pch_gpio_resume);
434 
435 static const struct pci_device_id pch_gpio_pcidev_id[] = {
436 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8803),
437 	  .driver_data = INTEL_EG20T_PCH },
438 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8014),
439 	  .driver_data = OKISEMI_ML7223m_IOH },
440 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8043),
441 	  .driver_data = OKISEMI_ML7223n_IOH },
442 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8803),
443 	  .driver_data = INTEL_EG20T_PCH },
444 	{ 0, }
445 };
446 MODULE_DEVICE_TABLE(pci, pch_gpio_pcidev_id);
447 
448 static struct pci_driver pch_gpio_driver = {
449 	.name = "pch_gpio",
450 	.id_table = pch_gpio_pcidev_id,
451 	.probe = pch_gpio_probe,
452 	.driver = {
453 		.pm = &pch_gpio_pm_ops,
454 	},
455 };
456 
457 module_pci_driver(pch_gpio_driver);
458 
459 MODULE_DESCRIPTION("PCH GPIO PCI Driver");
460 MODULE_LICENSE("GPL v2");
461