xref: /linux/drivers/gpio/gpio-pch.c (revision 55d0969c451159cff86949b38c39171cab962069)
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 #define PCI_DEVICE_ID_INTEL_EG20T_PCH		0x8803
41 #define PCI_DEVICE_ID_ROHM_ML7223m_IOH		0x8014
42 #define PCI_DEVICE_ID_ROHM_ML7223n_IOH		0x8043
43 #define PCI_DEVICE_ID_ROHM_EG20T_PCH		0x8803
44 
45 enum pch_type_t {
46 	INTEL_EG20T_PCH,
47 	OKISEMI_ML7223m_IOH, /* LAPIS Semiconductor ML7223 IOH PCIe Bus-m */
48 	OKISEMI_ML7223n_IOH  /* LAPIS Semiconductor ML7223 IOH PCIe Bus-n */
49 };
50 
51 /* Specifies number of GPIO PINS */
52 static int gpio_pins[] = {
53 	[INTEL_EG20T_PCH] = 12,
54 	[OKISEMI_ML7223m_IOH] = 8,
55 	[OKISEMI_ML7223n_IOH] = 8,
56 };
57 
58 /**
59  * struct pch_gpio_reg_data - The register store data.
60  * @ien_reg:	To store contents of IEN register.
61  * @imask_reg:	To store contents of IMASK register.
62  * @po_reg:	To store contents of PO register.
63  * @pm_reg:	To store contents of PM register.
64  * @im0_reg:	To store contents of IM0 register.
65  * @im1_reg:	To store contents of IM1 register.
66  * @gpio_use_sel_reg : To store contents of GPIO_USE_SEL register.
67  *		       (Only ML7223 Bus-n)
68  */
69 struct pch_gpio_reg_data {
70 	u32 ien_reg;
71 	u32 imask_reg;
72 	u32 po_reg;
73 	u32 pm_reg;
74 	u32 im0_reg;
75 	u32 im1_reg;
76 	u32 gpio_use_sel_reg;
77 };
78 
79 /**
80  * struct pch_gpio - GPIO private data structure.
81  * @base:			PCI base address of Memory mapped I/O register.
82  * @reg:			Memory mapped PCH GPIO register list.
83  * @dev:			Pointer to device structure.
84  * @gpio:			Data for GPIO infrastructure.
85  * @pch_gpio_reg:		Memory mapped Register data is saved here
86  *				when suspend.
87  * @irq_base:		Save base of IRQ number for interrupt
88  * @ioh:		IOH ID
89  * @spinlock:		Used for register access protection
90  */
91 struct pch_gpio {
92 	void __iomem *base;
93 	struct pch_regs __iomem *reg;
94 	struct device *dev;
95 	struct gpio_chip gpio;
96 	struct pch_gpio_reg_data pch_gpio_reg;
97 	int irq_base;
98 	enum pch_type_t ioh;
99 	spinlock_t spinlock;
100 };
101 
102 static void pch_gpio_set(struct gpio_chip *gpio, unsigned int nr, int val)
103 {
104 	u32 reg_val;
105 	struct pch_gpio *chip =	gpiochip_get_data(gpio);
106 	unsigned long flags;
107 
108 	spin_lock_irqsave(&chip->spinlock, flags);
109 	reg_val = ioread32(&chip->reg->po);
110 	if (val)
111 		reg_val |= BIT(nr);
112 	else
113 		reg_val &= ~BIT(nr);
114 
115 	iowrite32(reg_val, &chip->reg->po);
116 	spin_unlock_irqrestore(&chip->spinlock, flags);
117 }
118 
119 static int pch_gpio_get(struct gpio_chip *gpio, unsigned int nr)
120 {
121 	struct pch_gpio *chip =	gpiochip_get_data(gpio);
122 
123 	return !!(ioread32(&chip->reg->pi) & BIT(nr));
124 }
125 
126 static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned int nr,
127 				     int val)
128 {
129 	struct pch_gpio *chip =	gpiochip_get_data(gpio);
130 	u32 pm;
131 	u32 reg_val;
132 	unsigned long flags;
133 
134 	spin_lock_irqsave(&chip->spinlock, flags);
135 
136 	reg_val = ioread32(&chip->reg->po);
137 	if (val)
138 		reg_val |= BIT(nr);
139 	else
140 		reg_val &= ~BIT(nr);
141 	iowrite32(reg_val, &chip->reg->po);
142 
143 	pm = ioread32(&chip->reg->pm);
144 	pm &= BIT(gpio_pins[chip->ioh]) - 1;
145 	pm |= BIT(nr);
146 	iowrite32(pm, &chip->reg->pm);
147 
148 	spin_unlock_irqrestore(&chip->spinlock, flags);
149 
150 	return 0;
151 }
152 
153 static int pch_gpio_direction_input(struct gpio_chip *gpio, unsigned int nr)
154 {
155 	struct pch_gpio *chip =	gpiochip_get_data(gpio);
156 	u32 pm;
157 	unsigned long flags;
158 
159 	spin_lock_irqsave(&chip->spinlock, flags);
160 	pm = ioread32(&chip->reg->pm);
161 	pm &= BIT(gpio_pins[chip->ioh]) - 1;
162 	pm &= ~BIT(nr);
163 	iowrite32(pm, &chip->reg->pm);
164 	spin_unlock_irqrestore(&chip->spinlock, flags);
165 
166 	return 0;
167 }
168 
169 /*
170  * Save register configuration and disable interrupts.
171  */
172 static void __maybe_unused pch_gpio_save_reg_conf(struct pch_gpio *chip)
173 {
174 	chip->pch_gpio_reg.ien_reg = ioread32(&chip->reg->ien);
175 	chip->pch_gpio_reg.imask_reg = ioread32(&chip->reg->imask);
176 	chip->pch_gpio_reg.po_reg = ioread32(&chip->reg->po);
177 	chip->pch_gpio_reg.pm_reg = ioread32(&chip->reg->pm);
178 	chip->pch_gpio_reg.im0_reg = ioread32(&chip->reg->im0);
179 	if (chip->ioh == INTEL_EG20T_PCH)
180 		chip->pch_gpio_reg.im1_reg = ioread32(&chip->reg->im1);
181 	if (chip->ioh == OKISEMI_ML7223n_IOH)
182 		chip->pch_gpio_reg.gpio_use_sel_reg = ioread32(&chip->reg->gpio_use_sel);
183 }
184 
185 /*
186  * This function restores the register configuration of the GPIO device.
187  */
188 static void __maybe_unused pch_gpio_restore_reg_conf(struct pch_gpio *chip)
189 {
190 	iowrite32(chip->pch_gpio_reg.ien_reg, &chip->reg->ien);
191 	iowrite32(chip->pch_gpio_reg.imask_reg, &chip->reg->imask);
192 	/* to store contents of PO register */
193 	iowrite32(chip->pch_gpio_reg.po_reg, &chip->reg->po);
194 	/* to store contents of PM register */
195 	iowrite32(chip->pch_gpio_reg.pm_reg, &chip->reg->pm);
196 	iowrite32(chip->pch_gpio_reg.im0_reg, &chip->reg->im0);
197 	if (chip->ioh == INTEL_EG20T_PCH)
198 		iowrite32(chip->pch_gpio_reg.im1_reg, &chip->reg->im1);
199 	if (chip->ioh == OKISEMI_ML7223n_IOH)
200 		iowrite32(chip->pch_gpio_reg.gpio_use_sel_reg, &chip->reg->gpio_use_sel);
201 }
202 
203 static int pch_gpio_to_irq(struct gpio_chip *gpio, unsigned int offset)
204 {
205 	struct pch_gpio *chip = gpiochip_get_data(gpio);
206 
207 	return chip->irq_base + offset;
208 }
209 
210 static void pch_gpio_setup(struct pch_gpio *chip)
211 {
212 	struct gpio_chip *gpio = &chip->gpio;
213 
214 	gpio->label = dev_name(chip->dev);
215 	gpio->parent = chip->dev;
216 	gpio->owner = THIS_MODULE;
217 	gpio->direction_input = pch_gpio_direction_input;
218 	gpio->get = pch_gpio_get;
219 	gpio->direction_output = pch_gpio_direction_output;
220 	gpio->set = pch_gpio_set;
221 	gpio->base = -1;
222 	gpio->ngpio = gpio_pins[chip->ioh];
223 	gpio->can_sleep = false;
224 	gpio->to_irq = pch_gpio_to_irq;
225 }
226 
227 static int pch_irq_type(struct irq_data *d, unsigned int type)
228 {
229 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
230 	struct pch_gpio *chip = gc->private;
231 	u32 im, im_pos, val;
232 	u32 __iomem *im_reg;
233 	unsigned long flags;
234 	int ch, irq = d->irq;
235 
236 	ch = irq - chip->irq_base;
237 	if (irq < chip->irq_base + 8) {
238 		im_reg = &chip->reg->im0;
239 		im_pos = ch - 0;
240 	} else {
241 		im_reg = &chip->reg->im1;
242 		im_pos = ch - 8;
243 	}
244 	dev_dbg(chip->dev, "irq=%d type=%d ch=%d pos=%d\n", irq, type, ch, im_pos);
245 
246 	switch (type) {
247 	case IRQ_TYPE_EDGE_RISING:
248 		val = PCH_EDGE_RISING;
249 		break;
250 	case IRQ_TYPE_EDGE_FALLING:
251 		val = PCH_EDGE_FALLING;
252 		break;
253 	case IRQ_TYPE_EDGE_BOTH:
254 		val = PCH_EDGE_BOTH;
255 		break;
256 	case IRQ_TYPE_LEVEL_HIGH:
257 		val = PCH_LEVEL_H;
258 		break;
259 	case IRQ_TYPE_LEVEL_LOW:
260 		val = PCH_LEVEL_L;
261 		break;
262 	default:
263 		return 0;
264 	}
265 
266 	spin_lock_irqsave(&chip->spinlock, flags);
267 
268 	/* Set interrupt mode */
269 	im = ioread32(im_reg) & ~(PCH_IM_MASK << (im_pos * 4));
270 	iowrite32(im | (val << (im_pos * 4)), im_reg);
271 
272 	/* And the handler */
273 	if (type & IRQ_TYPE_LEVEL_MASK)
274 		irq_set_handler_locked(d, handle_level_irq);
275 	else if (type & IRQ_TYPE_EDGE_BOTH)
276 		irq_set_handler_locked(d, handle_edge_irq);
277 
278 	spin_unlock_irqrestore(&chip->spinlock, flags);
279 	return 0;
280 }
281 
282 static void pch_irq_unmask(struct irq_data *d)
283 {
284 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
285 	struct pch_gpio *chip = gc->private;
286 
287 	iowrite32(BIT(d->irq - chip->irq_base), &chip->reg->imaskclr);
288 }
289 
290 static void pch_irq_mask(struct irq_data *d)
291 {
292 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
293 	struct pch_gpio *chip = gc->private;
294 
295 	iowrite32(BIT(d->irq - chip->irq_base), &chip->reg->imask);
296 }
297 
298 static void pch_irq_ack(struct irq_data *d)
299 {
300 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
301 	struct pch_gpio *chip = gc->private;
302 
303 	iowrite32(BIT(d->irq - chip->irq_base), &chip->reg->iclr);
304 }
305 
306 static irqreturn_t pch_gpio_handler(int irq, void *dev_id)
307 {
308 	struct pch_gpio *chip = dev_id;
309 	unsigned long reg_val = ioread32(&chip->reg->istatus);
310 	int i;
311 
312 	dev_vdbg(chip->dev, "irq=%d  status=0x%lx\n", irq, reg_val);
313 
314 	reg_val &= BIT(gpio_pins[chip->ioh]) - 1;
315 
316 	for_each_set_bit(i, &reg_val, gpio_pins[chip->ioh])
317 		generic_handle_irq(chip->irq_base + i);
318 
319 	return IRQ_RETVAL(reg_val);
320 }
321 
322 static int pch_gpio_alloc_generic_chip(struct pch_gpio *chip,
323 				       unsigned int irq_start,
324 				       unsigned int num)
325 {
326 	struct irq_chip_generic *gc;
327 	struct irq_chip_type *ct;
328 	int rv;
329 
330 	gc = devm_irq_alloc_generic_chip(chip->dev, "pch_gpio", 1, irq_start,
331 					 chip->base, handle_simple_irq);
332 	if (!gc)
333 		return -ENOMEM;
334 
335 	gc->private = chip;
336 	ct = gc->chip_types;
337 
338 	ct->chip.irq_ack = pch_irq_ack;
339 	ct->chip.irq_mask = pch_irq_mask;
340 	ct->chip.irq_unmask = pch_irq_unmask;
341 	ct->chip.irq_set_type = pch_irq_type;
342 
343 	rv = devm_irq_setup_generic_chip(chip->dev, gc, IRQ_MSK(num),
344 					 IRQ_GC_INIT_MASK_CACHE,
345 					 IRQ_NOREQUEST | IRQ_NOPROBE, 0);
346 
347 	return rv;
348 }
349 
350 static int pch_gpio_probe(struct pci_dev *pdev,
351 				    const struct pci_device_id *id)
352 {
353 	struct device *dev = &pdev->dev;
354 	s32 ret;
355 	struct pch_gpio *chip;
356 	int irq_base;
357 
358 	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
359 	if (chip == NULL)
360 		return -ENOMEM;
361 
362 	chip->dev = dev;
363 	ret = pcim_enable_device(pdev);
364 	if (ret)
365 		return dev_err_probe(dev, ret, "Failed to enable PCI device\n");
366 
367 	ret = pcim_iomap_regions(pdev, BIT(1), KBUILD_MODNAME);
368 	if (ret)
369 		return dev_err_probe(dev, ret, "Failed to request and map PCI regions\n");
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 		return dev_err_probe(dev, ret, "Failed to register GPIO\n");
381 
382 	irq_base = devm_irq_alloc_descs(dev, -1, 0,
383 					gpio_pins[chip->ioh], NUMA_NO_NODE);
384 	if (irq_base < 0) {
385 		dev_warn(dev, "PCH gpio: Failed to get IRQ base num\n");
386 		chip->irq_base = -1;
387 		return 0;
388 	}
389 	chip->irq_base = irq_base;
390 
391 	/* Mask all interrupts, but enable them */
392 	iowrite32(BIT(gpio_pins[chip->ioh]) - 1, &chip->reg->imask);
393 	iowrite32(BIT(gpio_pins[chip->ioh]) - 1, &chip->reg->ien);
394 
395 	ret = devm_request_irq(dev, pdev->irq, pch_gpio_handler,
396 			       IRQF_SHARED, KBUILD_MODNAME, chip);
397 	if (ret)
398 		return dev_err_probe(dev, ret, "Failed to request IRQ\n");
399 
400 	return pch_gpio_alloc_generic_chip(chip, irq_base, gpio_pins[chip->ioh]);
401 }
402 
403 static int __maybe_unused pch_gpio_suspend(struct device *dev)
404 {
405 	struct pch_gpio *chip = dev_get_drvdata(dev);
406 	unsigned long flags;
407 
408 	spin_lock_irqsave(&chip->spinlock, flags);
409 	pch_gpio_save_reg_conf(chip);
410 	spin_unlock_irqrestore(&chip->spinlock, flags);
411 
412 	return 0;
413 }
414 
415 static int __maybe_unused pch_gpio_resume(struct device *dev)
416 {
417 	struct pch_gpio *chip = dev_get_drvdata(dev);
418 	unsigned long flags;
419 
420 	spin_lock_irqsave(&chip->spinlock, flags);
421 	iowrite32(0x01, &chip->reg->reset);
422 	iowrite32(0x00, &chip->reg->reset);
423 	pch_gpio_restore_reg_conf(chip);
424 	spin_unlock_irqrestore(&chip->spinlock, flags);
425 
426 	return 0;
427 }
428 
429 static SIMPLE_DEV_PM_OPS(pch_gpio_pm_ops, pch_gpio_suspend, pch_gpio_resume);
430 
431 static const struct pci_device_id pch_gpio_pcidev_id[] = {
432 	{ PCI_DEVICE_DATA(INTEL, EG20T_PCH, INTEL_EG20T_PCH) },
433 	{ PCI_DEVICE_DATA(ROHM, ML7223m_IOH, OKISEMI_ML7223m_IOH) },
434 	{ PCI_DEVICE_DATA(ROHM, ML7223n_IOH, OKISEMI_ML7223n_IOH) },
435 	{ PCI_DEVICE_DATA(ROHM, EG20T_PCH, INTEL_EG20T_PCH) },
436 	{ }
437 };
438 MODULE_DEVICE_TABLE(pci, pch_gpio_pcidev_id);
439 
440 static struct pci_driver pch_gpio_driver = {
441 	.name = "pch_gpio",
442 	.id_table = pch_gpio_pcidev_id,
443 	.probe = pch_gpio_probe,
444 	.driver = {
445 		.pm = &pch_gpio_pm_ops,
446 	},
447 };
448 
449 module_pci_driver(pch_gpio_driver);
450 
451 MODULE_DESCRIPTION("PCH GPIO PCI Driver");
452 MODULE_LICENSE("GPL v2");
453