xref: /openbmc/linux/drivers/gpio/gpio-pch.c (revision 95298d63)
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 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 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 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 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 offset)
200 {
201 	struct pch_gpio *chip = gpiochip_get_data(gpio);
202 	return chip->irq_base + offset;
203 }
204 
205 static void pch_gpio_setup(struct pch_gpio *chip)
206 {
207 	struct gpio_chip *gpio = &chip->gpio;
208 
209 	gpio->label = dev_name(chip->dev);
210 	gpio->parent = chip->dev;
211 	gpio->owner = THIS_MODULE;
212 	gpio->direction_input = pch_gpio_direction_input;
213 	gpio->get = pch_gpio_get;
214 	gpio->direction_output = pch_gpio_direction_output;
215 	gpio->set = pch_gpio_set;
216 	gpio->base = -1;
217 	gpio->ngpio = gpio_pins[chip->ioh];
218 	gpio->can_sleep = false;
219 	gpio->to_irq = pch_gpio_to_irq;
220 }
221 
222 static int pch_irq_type(struct irq_data *d, unsigned int type)
223 {
224 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
225 	struct pch_gpio *chip = gc->private;
226 	u32 im, im_pos, val;
227 	u32 __iomem *im_reg;
228 	unsigned long flags;
229 	int ch, irq = d->irq;
230 
231 	ch = irq - chip->irq_base;
232 	if (irq < chip->irq_base + 8) {
233 		im_reg = &chip->reg->im0;
234 		im_pos = ch - 0;
235 	} else {
236 		im_reg = &chip->reg->im1;
237 		im_pos = ch - 8;
238 	}
239 	dev_dbg(chip->dev, "irq=%d type=%d ch=%d pos=%d\n", irq, type, ch, im_pos);
240 
241 	switch (type) {
242 	case IRQ_TYPE_EDGE_RISING:
243 		val = PCH_EDGE_RISING;
244 		break;
245 	case IRQ_TYPE_EDGE_FALLING:
246 		val = PCH_EDGE_FALLING;
247 		break;
248 	case IRQ_TYPE_EDGE_BOTH:
249 		val = PCH_EDGE_BOTH;
250 		break;
251 	case IRQ_TYPE_LEVEL_HIGH:
252 		val = PCH_LEVEL_H;
253 		break;
254 	case IRQ_TYPE_LEVEL_LOW:
255 		val = PCH_LEVEL_L;
256 		break;
257 	default:
258 		return 0;
259 	}
260 
261 	spin_lock_irqsave(&chip->spinlock, flags);
262 
263 	/* Set interrupt mode */
264 	im = ioread32(im_reg) & ~(PCH_IM_MASK << (im_pos * 4));
265 	iowrite32(im | (val << (im_pos * 4)), im_reg);
266 
267 	/* And the handler */
268 	if (type & IRQ_TYPE_LEVEL_MASK)
269 		irq_set_handler_locked(d, handle_level_irq);
270 	else if (type & IRQ_TYPE_EDGE_BOTH)
271 		irq_set_handler_locked(d, handle_edge_irq);
272 
273 	spin_unlock_irqrestore(&chip->spinlock, flags);
274 	return 0;
275 }
276 
277 static void pch_irq_unmask(struct irq_data *d)
278 {
279 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
280 	struct pch_gpio *chip = gc->private;
281 
282 	iowrite32(BIT(d->irq - chip->irq_base), &chip->reg->imaskclr);
283 }
284 
285 static void pch_irq_mask(struct irq_data *d)
286 {
287 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
288 	struct pch_gpio *chip = gc->private;
289 
290 	iowrite32(BIT(d->irq - chip->irq_base), &chip->reg->imask);
291 }
292 
293 static void pch_irq_ack(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(BIT(d->irq - chip->irq_base), &chip->reg->iclr);
299 }
300 
301 static irqreturn_t pch_gpio_handler(int irq, void *dev_id)
302 {
303 	struct pch_gpio *chip = dev_id;
304 	unsigned long reg_val = ioread32(&chip->reg->istatus);
305 	int i;
306 
307 	dev_dbg(chip->dev, "irq=%d  status=0x%lx\n", irq, reg_val);
308 
309 	reg_val &= BIT(gpio_pins[chip->ioh]) - 1;
310 	for_each_set_bit(i, &reg_val, gpio_pins[chip->ioh])
311 		generic_handle_irq(chip->irq_base + i);
312 
313 	return IRQ_RETVAL(reg_val);
314 }
315 
316 static int pch_gpio_alloc_generic_chip(struct pch_gpio *chip,
317 				       unsigned int irq_start,
318 				       unsigned int num)
319 {
320 	struct irq_chip_generic *gc;
321 	struct irq_chip_type *ct;
322 	int rv;
323 
324 	gc = devm_irq_alloc_generic_chip(chip->dev, "pch_gpio", 1, irq_start,
325 					 chip->base, handle_simple_irq);
326 	if (!gc)
327 		return -ENOMEM;
328 
329 	gc->private = chip;
330 	ct = gc->chip_types;
331 
332 	ct->chip.irq_ack = pch_irq_ack;
333 	ct->chip.irq_mask = pch_irq_mask;
334 	ct->chip.irq_unmask = pch_irq_unmask;
335 	ct->chip.irq_set_type = pch_irq_type;
336 
337 	rv = devm_irq_setup_generic_chip(chip->dev, gc, IRQ_MSK(num),
338 					 IRQ_GC_INIT_MASK_CACHE,
339 					 IRQ_NOREQUEST | IRQ_NOPROBE, 0);
340 
341 	return rv;
342 }
343 
344 static int pch_gpio_probe(struct pci_dev *pdev,
345 				    const struct pci_device_id *id)
346 {
347 	s32 ret;
348 	struct pch_gpio *chip;
349 	int irq_base;
350 
351 	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
352 	if (chip == NULL)
353 		return -ENOMEM;
354 
355 	chip->dev = &pdev->dev;
356 	ret = pcim_enable_device(pdev);
357 	if (ret) {
358 		dev_err(&pdev->dev, "pci_enable_device FAILED");
359 		return ret;
360 	}
361 
362 	ret = pcim_iomap_regions(pdev, BIT(1), KBUILD_MODNAME);
363 	if (ret) {
364 		dev_err(&pdev->dev, "pci_request_regions FAILED-%d", ret);
365 		return ret;
366 	}
367 
368 	chip->base = pcim_iomap_table(pdev)[1];
369 
370 	if (pdev->device == 0x8803)
371 		chip->ioh = INTEL_EG20T_PCH;
372 	else if (pdev->device == 0x8014)
373 		chip->ioh = OKISEMI_ML7223m_IOH;
374 	else if (pdev->device == 0x8043)
375 		chip->ioh = OKISEMI_ML7223n_IOH;
376 
377 	chip->reg = chip->base;
378 	pci_set_drvdata(pdev, chip);
379 	spin_lock_init(&chip->spinlock);
380 	pch_gpio_setup(chip);
381 
382 	ret = devm_gpiochip_add_data(&pdev->dev, &chip->gpio, chip);
383 	if (ret) {
384 		dev_err(&pdev->dev, "PCH gpio: Failed to register GPIO\n");
385 		return ret;
386 	}
387 
388 	irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0,
389 					gpio_pins[chip->ioh], NUMA_NO_NODE);
390 	if (irq_base < 0) {
391 		dev_warn(&pdev->dev, "PCH gpio: Failed to get IRQ base num\n");
392 		chip->irq_base = -1;
393 		return 0;
394 	}
395 	chip->irq_base = irq_base;
396 
397 	/* Mask all interrupts, but enable them */
398 	iowrite32(BIT(gpio_pins[chip->ioh]) - 1, &chip->reg->imask);
399 	iowrite32(BIT(gpio_pins[chip->ioh]) - 1, &chip->reg->ien);
400 
401 	ret = devm_request_irq(&pdev->dev, pdev->irq, pch_gpio_handler,
402 			       IRQF_SHARED, KBUILD_MODNAME, chip);
403 	if (ret) {
404 		dev_err(&pdev->dev, "request_irq failed\n");
405 		return ret;
406 	}
407 
408 	return pch_gpio_alloc_generic_chip(chip, irq_base, gpio_pins[chip->ioh]);
409 }
410 
411 static int __maybe_unused pch_gpio_suspend(struct device *dev)
412 {
413 	struct pch_gpio *chip = dev_get_drvdata(dev);
414 	unsigned long flags;
415 
416 	spin_lock_irqsave(&chip->spinlock, flags);
417 	pch_gpio_save_reg_conf(chip);
418 	spin_unlock_irqrestore(&chip->spinlock, flags);
419 
420 	return 0;
421 }
422 
423 static int __maybe_unused pch_gpio_resume(struct device *dev)
424 {
425 	struct pch_gpio *chip = dev_get_drvdata(dev);
426 	unsigned long flags;
427 
428 	spin_lock_irqsave(&chip->spinlock, flags);
429 	iowrite32(0x01, &chip->reg->reset);
430 	iowrite32(0x00, &chip->reg->reset);
431 	pch_gpio_restore_reg_conf(chip);
432 	spin_unlock_irqrestore(&chip->spinlock, flags);
433 
434 	return 0;
435 }
436 
437 static SIMPLE_DEV_PM_OPS(pch_gpio_pm_ops, pch_gpio_suspend, pch_gpio_resume);
438 
439 static const struct pci_device_id pch_gpio_pcidev_id[] = {
440 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8803) },
441 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8014) },
442 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8043) },
443 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8803) },
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