xref: /openbmc/linux/drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gpio.c (revision 3dfbe6a73ae80429ccd268749e91c0d8d1526107)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2022 Microchip Technology Inc.
3 // pci1xxxx gpio driver
4 
5 #include <linux/module.h>
6 #include <linux/spinlock.h>
7 #include <linux/gpio/driver.h>
8 #include <linux/bio.h>
9 #include <linux/mutex.h>
10 #include <linux/kthread.h>
11 #include <linux/interrupt.h>
12 
13 #include "mchp_pci1xxxx_gp.h"
14 
15 #define PCI1XXXX_NR_PINS		93
16 #define PERI_GEN_RESET			0
17 #define OUT_EN_OFFSET(x)		((((x) / 32) * 4) + 0x400)
18 #define INP_EN_OFFSET(x)		((((x) / 32) * 4) + 0x400 + 0x10)
19 #define OUT_OFFSET(x)			((((x) / 32) * 4) + 0x400 + 0x20)
20 #define INP_OFFSET(x)			((((x) / 32) * 4) + 0x400 + 0x30)
21 #define PULLUP_OFFSET(x)		((((x) / 32) * 4) + 0x400 + 0x40)
22 #define PULLDOWN_OFFSET(x)		((((x) / 32) * 4) + 0x400 + 0x50)
23 #define OPENDRAIN_OFFSET(x)		((((x) / 32) * 4) + 0x400 + 0x60)
24 #define WAKEMASK_OFFSET(x)		((((x) / 32) * 4) + 0x400 + 0x70)
25 #define MODE_OFFSET(x)			((((x) / 32) * 4) + 0x400 + 0x80)
26 #define INTR_LO_TO_HI_EDGE_CONFIG(x)	((((x) / 32) * 4) + 0x400 + 0x90)
27 #define INTR_HI_TO_LO_EDGE_CONFIG(x)	((((x) / 32) * 4) + 0x400 + 0xA0)
28 #define INTR_LEVEL_CONFIG_OFFSET(x)	((((x) / 32) * 4) + 0x400 + 0xB0)
29 #define INTR_LEVEL_MASK_OFFSET(x)	((((x) / 32) * 4) + 0x400 + 0xC0)
30 #define INTR_STAT_OFFSET(x)		((((x) / 32) * 4) + 0x400 + 0xD0)
31 #define DEBOUNCE_OFFSET(x)		((((x) / 32) * 4) + 0x400 + 0xE0)
32 #define PIO_GLOBAL_CONFIG_OFFSET	(0x400 + 0xF0)
33 #define PIO_PCI_CTRL_REG_OFFSET	(0x400 + 0xF4)
34 #define INTR_MASK_OFFSET(x)		((((x) / 32) * 4) + 0x400 + 0x100)
35 #define INTR_STATUS_OFFSET(x)		(((x) * 4) + 0x400 + 0xD0)
36 
37 struct pci1xxxx_gpio {
38 	struct auxiliary_device *aux_dev;
39 	void __iomem *reg_base;
40 	raw_spinlock_t wa_lock;
41 	struct gpio_chip gpio;
42 	spinlock_t lock;
43 	int irq_base;
44 };
45 
pci1xxxx_gpio_get_direction(struct gpio_chip * gpio,unsigned int nr)46 static int pci1xxxx_gpio_get_direction(struct gpio_chip *gpio, unsigned int nr)
47 {
48 	struct pci1xxxx_gpio *priv = gpiochip_get_data(gpio);
49 	u32 data;
50 	int ret = -EINVAL;
51 
52 	data = readl(priv->reg_base + INP_EN_OFFSET(nr));
53 	if (data & BIT(nr % 32)) {
54 		ret =  1;
55 	} else {
56 		data = readl(priv->reg_base + OUT_EN_OFFSET(nr));
57 		if (data & BIT(nr % 32))
58 			ret =  0;
59 	}
60 
61 	return ret;
62 }
63 
pci1xxx_assign_bit(void __iomem * base_addr,unsigned int reg_offset,unsigned int bitpos,bool set)64 static inline void pci1xxx_assign_bit(void __iomem *base_addr, unsigned int reg_offset,
65 				      unsigned int bitpos, bool set)
66 {
67 	u32 data;
68 
69 	data = readl(base_addr + reg_offset);
70 	if (set)
71 		data |= BIT(bitpos);
72 	else
73 		data &= ~BIT(bitpos);
74 	writel(data, base_addr + reg_offset);
75 }
76 
pci1xxxx_gpio_direction_input(struct gpio_chip * gpio,unsigned int nr)77 static int pci1xxxx_gpio_direction_input(struct gpio_chip *gpio, unsigned int nr)
78 {
79 	struct pci1xxxx_gpio *priv = gpiochip_get_data(gpio);
80 	unsigned long flags;
81 
82 	spin_lock_irqsave(&priv->lock, flags);
83 	pci1xxx_assign_bit(priv->reg_base, INP_EN_OFFSET(nr), (nr % 32), true);
84 	pci1xxx_assign_bit(priv->reg_base, OUT_EN_OFFSET(nr), (nr % 32), false);
85 	spin_unlock_irqrestore(&priv->lock, flags);
86 
87 	return 0;
88 }
89 
pci1xxxx_gpio_get(struct gpio_chip * gpio,unsigned int nr)90 static int pci1xxxx_gpio_get(struct gpio_chip *gpio, unsigned int nr)
91 {
92 	struct pci1xxxx_gpio *priv = gpiochip_get_data(gpio);
93 
94 	return (readl(priv->reg_base + INP_OFFSET(nr)) >> (nr % 32)) & 1;
95 }
96 
pci1xxxx_gpio_direction_output(struct gpio_chip * gpio,unsigned int nr,int val)97 static int pci1xxxx_gpio_direction_output(struct gpio_chip *gpio,
98 					  unsigned int nr, int val)
99 {
100 	struct pci1xxxx_gpio *priv = gpiochip_get_data(gpio);
101 	unsigned long flags;
102 	u32 data;
103 
104 	spin_lock_irqsave(&priv->lock, flags);
105 	pci1xxx_assign_bit(priv->reg_base, INP_EN_OFFSET(nr), (nr % 32), false);
106 	pci1xxx_assign_bit(priv->reg_base, OUT_EN_OFFSET(nr), (nr % 32), true);
107 	data = readl(priv->reg_base + OUT_OFFSET(nr));
108 	if (val)
109 		data |= (1 << (nr % 32));
110 	else
111 		data &= ~(1 << (nr % 32));
112 	writel(data, priv->reg_base + OUT_OFFSET(nr));
113 	spin_unlock_irqrestore(&priv->lock, flags);
114 
115 	return 0;
116 }
117 
pci1xxxx_gpio_set(struct gpio_chip * gpio,unsigned int nr,int val)118 static void pci1xxxx_gpio_set(struct gpio_chip *gpio,
119 			      unsigned int nr, int val)
120 {
121 	struct pci1xxxx_gpio *priv = gpiochip_get_data(gpio);
122 	unsigned long flags;
123 
124 	spin_lock_irqsave(&priv->lock, flags);
125 	pci1xxx_assign_bit(priv->reg_base, OUT_OFFSET(nr), (nr % 32), val);
126 	spin_unlock_irqrestore(&priv->lock, flags);
127 }
128 
pci1xxxx_gpio_set_config(struct gpio_chip * gpio,unsigned int offset,unsigned long config)129 static int pci1xxxx_gpio_set_config(struct gpio_chip *gpio, unsigned int offset,
130 				    unsigned long config)
131 {
132 	struct pci1xxxx_gpio *priv = gpiochip_get_data(gpio);
133 	unsigned long flags;
134 	int ret = 0;
135 
136 	spin_lock_irqsave(&priv->lock, flags);
137 	switch (pinconf_to_config_param(config)) {
138 	case PIN_CONFIG_BIAS_PULL_UP:
139 		pci1xxx_assign_bit(priv->reg_base, PULLUP_OFFSET(offset), (offset % 32), true);
140 		break;
141 	case PIN_CONFIG_BIAS_PULL_DOWN:
142 		pci1xxx_assign_bit(priv->reg_base, PULLDOWN_OFFSET(offset), (offset % 32), true);
143 		break;
144 	case PIN_CONFIG_BIAS_DISABLE:
145 		pci1xxx_assign_bit(priv->reg_base, PULLUP_OFFSET(offset), (offset % 32), false);
146 		pci1xxx_assign_bit(priv->reg_base, PULLDOWN_OFFSET(offset), (offset % 32), false);
147 		break;
148 	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
149 		pci1xxx_assign_bit(priv->reg_base, OPENDRAIN_OFFSET(offset), (offset % 32), true);
150 		break;
151 	default:
152 		ret = -ENOTSUPP;
153 		break;
154 	}
155 	spin_unlock_irqrestore(&priv->lock, flags);
156 
157 	return ret;
158 }
159 
pci1xxxx_gpio_irq_ack(struct irq_data * data)160 static void pci1xxxx_gpio_irq_ack(struct irq_data *data)
161 {
162 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
163 	struct pci1xxxx_gpio *priv = gpiochip_get_data(chip);
164 	unsigned int gpio = irqd_to_hwirq(data);
165 	unsigned long flags;
166 
167 	spin_lock_irqsave(&priv->lock, flags);
168 	writel(BIT(gpio % 32), priv->reg_base + INTR_STAT_OFFSET(gpio));
169 	spin_unlock_irqrestore(&priv->lock, flags);
170 }
171 
pci1xxxx_gpio_irq_set_mask(struct irq_data * data,bool set)172 static void pci1xxxx_gpio_irq_set_mask(struct irq_data *data, bool set)
173 {
174 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
175 	struct pci1xxxx_gpio *priv = gpiochip_get_data(chip);
176 	unsigned int gpio = irqd_to_hwirq(data);
177 	unsigned long flags;
178 
179 	if (!set)
180 		gpiochip_enable_irq(chip, gpio);
181 	spin_lock_irqsave(&priv->lock, flags);
182 	pci1xxx_assign_bit(priv->reg_base, INTR_MASK_OFFSET(gpio), (gpio % 32), set);
183 	spin_unlock_irqrestore(&priv->lock, flags);
184 	if (set)
185 		gpiochip_disable_irq(chip, gpio);
186 }
187 
pci1xxxx_gpio_irq_mask(struct irq_data * data)188 static void pci1xxxx_gpio_irq_mask(struct irq_data *data)
189 {
190 	pci1xxxx_gpio_irq_set_mask(data, true);
191 }
192 
pci1xxxx_gpio_irq_unmask(struct irq_data * data)193 static void pci1xxxx_gpio_irq_unmask(struct irq_data *data)
194 {
195 	pci1xxxx_gpio_irq_set_mask(data, false);
196 }
197 
pci1xxxx_gpio_set_type(struct irq_data * data,unsigned int trigger_type)198 static int pci1xxxx_gpio_set_type(struct irq_data *data, unsigned int trigger_type)
199 {
200 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
201 	struct pci1xxxx_gpio *priv = gpiochip_get_data(chip);
202 	unsigned int gpio = irqd_to_hwirq(data);
203 	unsigned int bitpos = gpio % 32;
204 
205 	if (trigger_type & IRQ_TYPE_EDGE_FALLING) {
206 		pci1xxx_assign_bit(priv->reg_base, INTR_HI_TO_LO_EDGE_CONFIG(gpio),
207 				   bitpos, false);
208 		pci1xxx_assign_bit(priv->reg_base, MODE_OFFSET(gpio),
209 				   bitpos, false);
210 		irq_set_handler_locked(data, handle_edge_irq);
211 	} else {
212 		pci1xxx_assign_bit(priv->reg_base, INTR_HI_TO_LO_EDGE_CONFIG(gpio),
213 				   bitpos, true);
214 	}
215 
216 	if (trigger_type & IRQ_TYPE_EDGE_RISING) {
217 		pci1xxx_assign_bit(priv->reg_base, INTR_LO_TO_HI_EDGE_CONFIG(gpio),
218 				   bitpos, false);
219 		pci1xxx_assign_bit(priv->reg_base, MODE_OFFSET(gpio), bitpos,
220 				   false);
221 		irq_set_handler_locked(data, handle_edge_irq);
222 	} else {
223 		pci1xxx_assign_bit(priv->reg_base, INTR_LO_TO_HI_EDGE_CONFIG(gpio),
224 				   bitpos, true);
225 	}
226 
227 	if (trigger_type & IRQ_TYPE_LEVEL_LOW) {
228 		pci1xxx_assign_bit(priv->reg_base, INTR_LEVEL_CONFIG_OFFSET(gpio),
229 				   bitpos, true);
230 		pci1xxx_assign_bit(priv->reg_base, INTR_LEVEL_MASK_OFFSET(gpio),
231 				   bitpos, false);
232 		pci1xxx_assign_bit(priv->reg_base, MODE_OFFSET(gpio), bitpos,
233 				   true);
234 		irq_set_handler_locked(data, handle_edge_irq);
235 	}
236 
237 	if (trigger_type & IRQ_TYPE_LEVEL_HIGH) {
238 		pci1xxx_assign_bit(priv->reg_base, INTR_LEVEL_CONFIG_OFFSET(gpio),
239 				   bitpos, false);
240 		pci1xxx_assign_bit(priv->reg_base, INTR_LEVEL_MASK_OFFSET(gpio),
241 				   bitpos, false);
242 		pci1xxx_assign_bit(priv->reg_base, MODE_OFFSET(gpio), bitpos,
243 				   true);
244 		irq_set_handler_locked(data, handle_edge_irq);
245 	}
246 
247 	if ((!(trigger_type & IRQ_TYPE_LEVEL_LOW)) && (!(trigger_type & IRQ_TYPE_LEVEL_HIGH)))
248 		pci1xxx_assign_bit(priv->reg_base, INTR_LEVEL_MASK_OFFSET(gpio), bitpos, true);
249 
250 	return true;
251 }
252 
pci1xxxx_gpio_irq_handler(int irq,void * dev_id)253 static irqreturn_t pci1xxxx_gpio_irq_handler(int irq, void *dev_id)
254 {
255 	struct pci1xxxx_gpio *priv = dev_id;
256 	struct gpio_chip *gc =  &priv->gpio;
257 	unsigned long int_status = 0;
258 	unsigned long wa_flags;
259 	unsigned long flags;
260 	u8 pincount;
261 	int bit;
262 	u8 gpiobank;
263 
264 	spin_lock_irqsave(&priv->lock, flags);
265 	pci1xxx_assign_bit(priv->reg_base, PIO_GLOBAL_CONFIG_OFFSET, 16, true);
266 	spin_unlock_irqrestore(&priv->lock, flags);
267 	for (gpiobank = 0; gpiobank < 3; gpiobank++) {
268 		spin_lock_irqsave(&priv->lock, flags);
269 		int_status = readl(priv->reg_base + INTR_STATUS_OFFSET(gpiobank));
270 		spin_unlock_irqrestore(&priv->lock, flags);
271 		if (gpiobank == 2)
272 			pincount = 29;
273 		else
274 			pincount = 32;
275 		for_each_set_bit(bit, &int_status, pincount) {
276 			unsigned int irq;
277 
278 			spin_lock_irqsave(&priv->lock, flags);
279 			writel(BIT(bit), priv->reg_base + INTR_STATUS_OFFSET(gpiobank));
280 			spin_unlock_irqrestore(&priv->lock, flags);
281 			irq = irq_find_mapping(gc->irq.domain, (bit + (gpiobank * 32)));
282 			raw_spin_lock_irqsave(&priv->wa_lock, wa_flags);
283 			generic_handle_irq(irq);
284 			raw_spin_unlock_irqrestore(&priv->wa_lock, wa_flags);
285 		}
286 	}
287 	spin_lock_irqsave(&priv->lock, flags);
288 	pci1xxx_assign_bit(priv->reg_base, PIO_GLOBAL_CONFIG_OFFSET, 16, false);
289 	spin_unlock_irqrestore(&priv->lock, flags);
290 
291 	return IRQ_HANDLED;
292 }
293 
294 static const struct irq_chip pci1xxxx_gpio_irqchip = {
295 	.name = "pci1xxxx_gpio",
296 	.irq_ack = pci1xxxx_gpio_irq_ack,
297 	.irq_mask = pci1xxxx_gpio_irq_mask,
298 	.irq_unmask = pci1xxxx_gpio_irq_unmask,
299 	.irq_set_type = pci1xxxx_gpio_set_type,
300 	.flags = IRQCHIP_IMMUTABLE,
301 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
302 };
303 
pci1xxxx_gpio_suspend(struct device * dev)304 static int pci1xxxx_gpio_suspend(struct device *dev)
305 {
306 	struct pci1xxxx_gpio *priv = dev_get_drvdata(dev);
307 	unsigned long flags;
308 
309 	spin_lock_irqsave(&priv->lock, flags);
310 	pci1xxx_assign_bit(priv->reg_base, PIO_GLOBAL_CONFIG_OFFSET,
311 			   16, true);
312 	pci1xxx_assign_bit(priv->reg_base, PIO_GLOBAL_CONFIG_OFFSET,
313 			   17, false);
314 	pci1xxx_assign_bit(priv->reg_base, PERI_GEN_RESET, 16, true);
315 	spin_unlock_irqrestore(&priv->lock, flags);
316 
317 	return 0;
318 }
319 
pci1xxxx_gpio_resume(struct device * dev)320 static int pci1xxxx_gpio_resume(struct device *dev)
321 {
322 	struct pci1xxxx_gpio *priv = dev_get_drvdata(dev);
323 	unsigned long flags;
324 
325 	spin_lock_irqsave(&priv->lock, flags);
326 	pci1xxx_assign_bit(priv->reg_base, PIO_GLOBAL_CONFIG_OFFSET,
327 			   17, true);
328 	pci1xxx_assign_bit(priv->reg_base, PIO_GLOBAL_CONFIG_OFFSET,
329 			   16, false);
330 	pci1xxx_assign_bit(priv->reg_base, PERI_GEN_RESET, 16, false);
331 	spin_unlock_irqrestore(&priv->lock, flags);
332 
333 	return 0;
334 }
335 
pci1xxxx_gpio_setup(struct pci1xxxx_gpio * priv,int irq)336 static int pci1xxxx_gpio_setup(struct pci1xxxx_gpio *priv, int irq)
337 {
338 	struct gpio_chip *gchip = &priv->gpio;
339 	struct gpio_irq_chip *girq;
340 	int retval;
341 
342 	gchip->label = dev_name(&priv->aux_dev->dev);
343 	gchip->parent = &priv->aux_dev->dev;
344 	gchip->owner = THIS_MODULE;
345 	gchip->direction_input = pci1xxxx_gpio_direction_input;
346 	gchip->direction_output = pci1xxxx_gpio_direction_output;
347 	gchip->get_direction = pci1xxxx_gpio_get_direction;
348 	gchip->get = pci1xxxx_gpio_get;
349 	gchip->set = pci1xxxx_gpio_set;
350 	gchip->set_config = pci1xxxx_gpio_set_config;
351 	gchip->dbg_show = NULL;
352 	gchip->base = -1;
353 	gchip->ngpio =  PCI1XXXX_NR_PINS;
354 	gchip->can_sleep = false;
355 
356 	retval = devm_request_threaded_irq(&priv->aux_dev->dev, irq,
357 					   NULL, pci1xxxx_gpio_irq_handler,
358 					   IRQF_ONESHOT, "PCI1xxxxGPIO", priv);
359 
360 	if (retval)
361 		return retval;
362 
363 	girq = &priv->gpio.irq;
364 	gpio_irq_chip_set_chip(girq, &pci1xxxx_gpio_irqchip);
365 	girq->parent_handler = NULL;
366 	girq->num_parents = 0;
367 	girq->parents = NULL;
368 	girq->default_type = IRQ_TYPE_NONE;
369 	girq->handler = handle_bad_irq;
370 
371 	return 0;
372 }
373 
pci1xxxx_gpio_probe(struct auxiliary_device * aux_dev,const struct auxiliary_device_id * id)374 static int pci1xxxx_gpio_probe(struct auxiliary_device *aux_dev,
375 			       const struct auxiliary_device_id *id)
376 
377 {
378 	struct auxiliary_device_wrapper *aux_dev_wrapper;
379 	struct gp_aux_data_type *pdata;
380 	struct pci1xxxx_gpio *priv;
381 	int retval;
382 
383 	aux_dev_wrapper = (struct auxiliary_device_wrapper *)
384 			  container_of(aux_dev, struct auxiliary_device_wrapper, aux_dev);
385 
386 	pdata = &aux_dev_wrapper->gp_aux_data;
387 
388 	if (!pdata)
389 		return -EINVAL;
390 
391 	priv = devm_kzalloc(&aux_dev->dev, sizeof(struct pci1xxxx_gpio), GFP_KERNEL);
392 	if (!priv)
393 		return -ENOMEM;
394 
395 	spin_lock_init(&priv->lock);
396 	priv->aux_dev = aux_dev;
397 
398 	if (!devm_request_mem_region(&aux_dev->dev, pdata->region_start, 0x800, aux_dev->name))
399 		return -EBUSY;
400 
401 	priv->reg_base = devm_ioremap(&aux_dev->dev, pdata->region_start, 0x800);
402 	if (!priv->reg_base)
403 		return -ENOMEM;
404 
405 	writel(0x0264, (priv->reg_base + 0x400 + 0xF0));
406 
407 	retval = pci1xxxx_gpio_setup(priv, pdata->irq_num);
408 
409 	if (retval < 0)
410 		return retval;
411 
412 	dev_set_drvdata(&aux_dev->dev, priv);
413 
414 	return devm_gpiochip_add_data(&aux_dev->dev, &priv->gpio, priv);
415 }
416 
417 static DEFINE_SIMPLE_DEV_PM_OPS(pci1xxxx_gpio_pm_ops, pci1xxxx_gpio_suspend, pci1xxxx_gpio_resume);
418 
419 static const struct auxiliary_device_id pci1xxxx_gpio_auxiliary_id_table[] = {
420 	{.name = "mchp_pci1xxxx_gp.gp_gpio"},
421 	{}
422 };
423 MODULE_DEVICE_TABLE(auxiliary, pci1xxxx_gpio_auxiliary_id_table);
424 
425 static struct auxiliary_driver pci1xxxx_gpio_driver = {
426 	.driver = {
427 		.name = "PCI1xxxxGPIO",
428 		.pm = &pci1xxxx_gpio_pm_ops,
429 		},
430 	.probe = pci1xxxx_gpio_probe,
431 	.id_table = pci1xxxx_gpio_auxiliary_id_table
432 };
433 module_auxiliary_driver(pci1xxxx_gpio_driver);
434 
435 MODULE_DESCRIPTION("Microchip Technology Inc. PCI1xxxx GPIO controller");
436 MODULE_AUTHOR("Kumaravel Thiagarajan <kumaravel.thiagarajan@microchip.com>");
437 MODULE_LICENSE("GPL");
438