xref: /linux/drivers/gpio/gpio-pch.c (revision fcb117e0758d1462128a50c5788555e03b48833b)
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 
pch_gpio_set(struct gpio_chip * gpio,unsigned int nr,int val)102 static int 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 	return 0;
119 }
120 
pch_gpio_get(struct gpio_chip * gpio,unsigned int nr)121 static int pch_gpio_get(struct gpio_chip *gpio, unsigned int nr)
122 {
123 	struct pch_gpio *chip =	gpiochip_get_data(gpio);
124 
125 	return !!(ioread32(&chip->reg->pi) & BIT(nr));
126 }
127 
pch_gpio_direction_output(struct gpio_chip * gpio,unsigned int nr,int val)128 static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned int nr,
129 				     int val)
130 {
131 	struct pch_gpio *chip =	gpiochip_get_data(gpio);
132 	u32 pm;
133 	u32 reg_val;
134 	unsigned long flags;
135 
136 	spin_lock_irqsave(&chip->spinlock, flags);
137 
138 	reg_val = ioread32(&chip->reg->po);
139 	if (val)
140 		reg_val |= BIT(nr);
141 	else
142 		reg_val &= ~BIT(nr);
143 	iowrite32(reg_val, &chip->reg->po);
144 
145 	pm = ioread32(&chip->reg->pm);
146 	pm &= BIT(gpio_pins[chip->ioh]) - 1;
147 	pm |= BIT(nr);
148 	iowrite32(pm, &chip->reg->pm);
149 
150 	spin_unlock_irqrestore(&chip->spinlock, flags);
151 
152 	return 0;
153 }
154 
pch_gpio_direction_input(struct gpio_chip * gpio,unsigned int nr)155 static int pch_gpio_direction_input(struct gpio_chip *gpio, unsigned int nr)
156 {
157 	struct pch_gpio *chip =	gpiochip_get_data(gpio);
158 	u32 pm;
159 	unsigned long flags;
160 
161 	spin_lock_irqsave(&chip->spinlock, flags);
162 	pm = ioread32(&chip->reg->pm);
163 	pm &= BIT(gpio_pins[chip->ioh]) - 1;
164 	pm &= ~BIT(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  */
pch_gpio_save_reg_conf(struct pch_gpio * chip)174 static void __maybe_unused 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 = ioread32(&chip->reg->gpio_use_sel);
185 }
186 
187 /*
188  * This function restores the register configuration of the GPIO device.
189  */
pch_gpio_restore_reg_conf(struct pch_gpio * chip)190 static void __maybe_unused pch_gpio_restore_reg_conf(struct pch_gpio *chip)
191 {
192 	iowrite32(chip->pch_gpio_reg.ien_reg, &chip->reg->ien);
193 	iowrite32(chip->pch_gpio_reg.imask_reg, &chip->reg->imask);
194 	/* to store contents of PO register */
195 	iowrite32(chip->pch_gpio_reg.po_reg, &chip->reg->po);
196 	/* to store contents of PM register */
197 	iowrite32(chip->pch_gpio_reg.pm_reg, &chip->reg->pm);
198 	iowrite32(chip->pch_gpio_reg.im0_reg, &chip->reg->im0);
199 	if (chip->ioh == INTEL_EG20T_PCH)
200 		iowrite32(chip->pch_gpio_reg.im1_reg, &chip->reg->im1);
201 	if (chip->ioh == OKISEMI_ML7223n_IOH)
202 		iowrite32(chip->pch_gpio_reg.gpio_use_sel_reg, &chip->reg->gpio_use_sel);
203 }
204 
pch_gpio_to_irq(struct gpio_chip * gpio,unsigned int offset)205 static int pch_gpio_to_irq(struct gpio_chip *gpio, unsigned int offset)
206 {
207 	struct pch_gpio *chip = gpiochip_get_data(gpio);
208 
209 	return chip->irq_base + offset;
210 }
211 
pch_gpio_setup(struct pch_gpio * chip)212 static void pch_gpio_setup(struct pch_gpio *chip)
213 {
214 	struct gpio_chip *gpio = &chip->gpio;
215 
216 	gpio->label = dev_name(chip->dev);
217 	gpio->parent = chip->dev;
218 	gpio->owner = THIS_MODULE;
219 	gpio->direction_input = pch_gpio_direction_input;
220 	gpio->get = pch_gpio_get;
221 	gpio->direction_output = pch_gpio_direction_output;
222 	gpio->set_rv = pch_gpio_set;
223 	gpio->base = -1;
224 	gpio->ngpio = gpio_pins[chip->ioh];
225 	gpio->can_sleep = false;
226 	gpio->to_irq = pch_gpio_to_irq;
227 }
228 
pch_irq_type(struct irq_data * d,unsigned int type)229 static int pch_irq_type(struct irq_data *d, unsigned int type)
230 {
231 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
232 	struct pch_gpio *chip = gc->private;
233 	u32 im, im_pos, val;
234 	u32 __iomem *im_reg;
235 	unsigned long flags;
236 	int ch, irq = d->irq;
237 
238 	ch = irq - chip->irq_base;
239 	if (irq < chip->irq_base + 8) {
240 		im_reg = &chip->reg->im0;
241 		im_pos = ch - 0;
242 	} else {
243 		im_reg = &chip->reg->im1;
244 		im_pos = ch - 8;
245 	}
246 	dev_dbg(chip->dev, "irq=%d type=%d ch=%d pos=%d\n", irq, type, ch, im_pos);
247 
248 	switch (type) {
249 	case IRQ_TYPE_EDGE_RISING:
250 		val = PCH_EDGE_RISING;
251 		break;
252 	case IRQ_TYPE_EDGE_FALLING:
253 		val = PCH_EDGE_FALLING;
254 		break;
255 	case IRQ_TYPE_EDGE_BOTH:
256 		val = PCH_EDGE_BOTH;
257 		break;
258 	case IRQ_TYPE_LEVEL_HIGH:
259 		val = PCH_LEVEL_H;
260 		break;
261 	case IRQ_TYPE_LEVEL_LOW:
262 		val = PCH_LEVEL_L;
263 		break;
264 	default:
265 		return 0;
266 	}
267 
268 	spin_lock_irqsave(&chip->spinlock, flags);
269 
270 	/* Set interrupt mode */
271 	im = ioread32(im_reg) & ~(PCH_IM_MASK << (im_pos * 4));
272 	iowrite32(im | (val << (im_pos * 4)), im_reg);
273 
274 	/* And the handler */
275 	if (type & IRQ_TYPE_LEVEL_MASK)
276 		irq_set_handler_locked(d, handle_level_irq);
277 	else if (type & IRQ_TYPE_EDGE_BOTH)
278 		irq_set_handler_locked(d, handle_edge_irq);
279 
280 	spin_unlock_irqrestore(&chip->spinlock, flags);
281 	return 0;
282 }
283 
pch_irq_unmask(struct irq_data * d)284 static void pch_irq_unmask(struct irq_data *d)
285 {
286 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
287 	struct pch_gpio *chip = gc->private;
288 
289 	iowrite32(BIT(d->irq - chip->irq_base), &chip->reg->imaskclr);
290 }
291 
pch_irq_mask(struct irq_data * d)292 static void pch_irq_mask(struct irq_data *d)
293 {
294 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
295 	struct pch_gpio *chip = gc->private;
296 
297 	iowrite32(BIT(d->irq - chip->irq_base), &chip->reg->imask);
298 }
299 
pch_irq_ack(struct irq_data * d)300 static void pch_irq_ack(struct irq_data *d)
301 {
302 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
303 	struct pch_gpio *chip = gc->private;
304 
305 	iowrite32(BIT(d->irq - chip->irq_base), &chip->reg->iclr);
306 }
307 
pch_gpio_handler(int irq,void * dev_id)308 static irqreturn_t pch_gpio_handler(int irq, void *dev_id)
309 {
310 	struct pch_gpio *chip = dev_id;
311 	unsigned long reg_val = ioread32(&chip->reg->istatus);
312 	int i;
313 
314 	dev_vdbg(chip->dev, "irq=%d  status=0x%lx\n", irq, reg_val);
315 
316 	reg_val &= BIT(gpio_pins[chip->ioh]) - 1;
317 
318 	for_each_set_bit(i, &reg_val, gpio_pins[chip->ioh])
319 		generic_handle_irq(chip->irq_base + i);
320 
321 	return IRQ_RETVAL(reg_val);
322 }
323 
pch_gpio_alloc_generic_chip(struct pch_gpio * chip,unsigned int irq_start,unsigned int num)324 static int pch_gpio_alloc_generic_chip(struct pch_gpio *chip,
325 				       unsigned int irq_start,
326 				       unsigned int num)
327 {
328 	struct irq_chip_generic *gc;
329 	struct irq_chip_type *ct;
330 	int rv;
331 
332 	gc = devm_irq_alloc_generic_chip(chip->dev, "pch_gpio", 1, irq_start,
333 					 chip->base, handle_simple_irq);
334 	if (!gc)
335 		return -ENOMEM;
336 
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 	rv = devm_irq_setup_generic_chip(chip->dev, gc, IRQ_MSK(num),
346 					 IRQ_GC_INIT_MASK_CACHE,
347 					 IRQ_NOREQUEST | IRQ_NOPROBE, 0);
348 
349 	return rv;
350 }
351 
pch_gpio_probe(struct pci_dev * pdev,const struct pci_device_id * id)352 static int pch_gpio_probe(struct pci_dev *pdev,
353 				    const struct pci_device_id *id)
354 {
355 	struct device *dev = &pdev->dev;
356 	s32 ret;
357 	struct pch_gpio *chip;
358 	int irq_base;
359 
360 	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
361 	if (chip == NULL)
362 		return -ENOMEM;
363 
364 	chip->dev = dev;
365 	ret = pcim_enable_device(pdev);
366 	if (ret)
367 		return dev_err_probe(dev, ret, "Failed to enable PCI device\n");
368 
369 	ret = pcim_iomap_regions(pdev, BIT(1), KBUILD_MODNAME);
370 	if (ret)
371 		return dev_err_probe(dev, ret, "Failed to request and map PCI regions\n");
372 
373 	chip->base = pcim_iomap_table(pdev)[1];
374 	chip->ioh = id->driver_data;
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(dev, &chip->gpio, chip);
381 	if (ret)
382 		return dev_err_probe(dev, ret, "Failed to register GPIO\n");
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 		return dev_err_probe(dev, ret, "Failed to request IRQ\n");
401 
402 	return pch_gpio_alloc_generic_chip(chip, irq_base, gpio_pins[chip->ioh]);
403 }
404 
pch_gpio_suspend(struct device * dev)405 static int __maybe_unused pch_gpio_suspend(struct device *dev)
406 {
407 	struct pch_gpio *chip = dev_get_drvdata(dev);
408 	unsigned long flags;
409 
410 	spin_lock_irqsave(&chip->spinlock, flags);
411 	pch_gpio_save_reg_conf(chip);
412 	spin_unlock_irqrestore(&chip->spinlock, flags);
413 
414 	return 0;
415 }
416 
pch_gpio_resume(struct device * dev)417 static int __maybe_unused pch_gpio_resume(struct device *dev)
418 {
419 	struct pch_gpio *chip = dev_get_drvdata(dev);
420 	unsigned long flags;
421 
422 	spin_lock_irqsave(&chip->spinlock, flags);
423 	iowrite32(0x01, &chip->reg->reset);
424 	iowrite32(0x00, &chip->reg->reset);
425 	pch_gpio_restore_reg_conf(chip);
426 	spin_unlock_irqrestore(&chip->spinlock, flags);
427 
428 	return 0;
429 }
430 
431 static SIMPLE_DEV_PM_OPS(pch_gpio_pm_ops, pch_gpio_suspend, pch_gpio_resume);
432 
433 static const struct pci_device_id pch_gpio_pcidev_id[] = {
434 	{ PCI_DEVICE_DATA(INTEL, EG20T_PCH, INTEL_EG20T_PCH) },
435 	{ PCI_DEVICE_DATA(ROHM, ML7223m_IOH, OKISEMI_ML7223m_IOH) },
436 	{ PCI_DEVICE_DATA(ROHM, ML7223n_IOH, OKISEMI_ML7223n_IOH) },
437 	{ PCI_DEVICE_DATA(ROHM, EG20T_PCH, INTEL_EG20T_PCH) },
438 	{ }
439 };
440 MODULE_DEVICE_TABLE(pci, pch_gpio_pcidev_id);
441 
442 static struct pci_driver pch_gpio_driver = {
443 	.name = "pch_gpio",
444 	.id_table = pch_gpio_pcidev_id,
445 	.probe = pch_gpio_probe,
446 	.driver = {
447 		.pm = &pch_gpio_pm_ops,
448 	},
449 };
450 
451 module_pci_driver(pch_gpio_driver);
452 
453 MODULE_DESCRIPTION("PCH GPIO PCI Driver");
454 MODULE_LICENSE("GPL v2");
455