xref: /linux/drivers/gpio/gpio-xgene-sb.c (revision 55a42f78ffd386e01a5404419f8c5ded7db70a21)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * AppliedMicro X-Gene SoC GPIO-Standby Driver
4  *
5  * Copyright (c) 2014, Applied Micro Circuits Corporation
6  * Author:	Tin Huynh <tnhuynh@apm.com>.
7  *		Y Vo <yvo@apm.com>.
8  *		Quan Nguyen <qnguyen@apm.com>.
9  */
10 
11 #include <linux/device.h>
12 #include <linux/err.h>
13 #include <linux/io.h>
14 #include <linux/irq.h>
15 #include <linux/irqdomain.h>
16 #include <linux/mod_devicetable.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/platform_device.h>
20 #include <linux/property.h>
21 #include <linux/types.h>
22 
23 #include <linux/gpio/driver.h>
24 #include <linux/gpio/generic.h>
25 
26 #include "gpiolib-acpi.h"
27 
28 #define XGENE_DFLT_MAX_NGPIO		22
29 #define XGENE_DFLT_MAX_NIRQ		6
30 #define XGENE_DFLT_IRQ_START_PIN	8
31 #define GPIO_MASK(x)			(1U << ((x) % 32))
32 
33 #define MPA_GPIO_INT_LVL		0x0290
34 #define MPA_GPIO_OE_ADDR		0x029c
35 #define MPA_GPIO_OUT_ADDR		0x02a0
36 #define MPA_GPIO_IN_ADDR 		0x02a4
37 #define MPA_GPIO_SEL_LO 		0x0294
38 
39 #define GPIO_INT_LEVEL_H	0x000001
40 #define GPIO_INT_LEVEL_L	0x000000
41 
42 /**
43  * struct xgene_gpio_sb - GPIO-Standby private data structure.
44  * @chip:			Generic GPIO chip data
45  * @regs:			GPIO register base offset
46  * @irq_domain:			GPIO interrupt domain
47  * @irq_start:			GPIO pin that start support interrupt
48  * @nirq:			Number of GPIO pins that supports interrupt
49  * @parent_irq_base:		Start parent HWIRQ
50  */
51 struct xgene_gpio_sb {
52 	struct gpio_generic_chip chip;
53 	void __iomem		*regs;
54 	struct irq_domain	*irq_domain;
55 	u16			irq_start;
56 	u16			nirq;
57 	u16			parent_irq_base;
58 };
59 
60 #define HWIRQ_TO_GPIO(priv, hwirq) ((hwirq) + (priv)->irq_start)
61 #define GPIO_TO_HWIRQ(priv, gpio) ((gpio) - (priv)->irq_start)
62 
63 static void xgene_gpio_set_bit(struct gpio_chip *gc,
64 				void __iomem *reg, u32 gpio, int val)
65 {
66 	struct gpio_generic_chip *chip = to_gpio_generic_chip(gc);
67 	u32 data;
68 
69 	data = gpio_generic_read_reg(chip, reg);
70 	if (val)
71 		data |= GPIO_MASK(gpio);
72 	else
73 		data &= ~GPIO_MASK(gpio);
74 	gpio_generic_write_reg(chip, reg, data);
75 }
76 
77 static int xgene_gpio_sb_irq_set_type(struct irq_data *d, unsigned int type)
78 {
79 	struct xgene_gpio_sb *priv = irq_data_get_irq_chip_data(d);
80 	int gpio = HWIRQ_TO_GPIO(priv, d->hwirq);
81 	int lvl_type = GPIO_INT_LEVEL_H;
82 
83 	switch (type & IRQ_TYPE_SENSE_MASK) {
84 	case IRQ_TYPE_EDGE_RISING:
85 	case IRQ_TYPE_LEVEL_HIGH:
86 		lvl_type = GPIO_INT_LEVEL_H;
87 		break;
88 	case IRQ_TYPE_EDGE_FALLING:
89 	case IRQ_TYPE_LEVEL_LOW:
90 		lvl_type = GPIO_INT_LEVEL_L;
91 		break;
92 	default:
93 		break;
94 	}
95 
96 	xgene_gpio_set_bit(&priv->chip.gc, priv->regs + MPA_GPIO_SEL_LO,
97 			gpio * 2, 1);
98 	xgene_gpio_set_bit(&priv->chip.gc, priv->regs + MPA_GPIO_INT_LVL,
99 			d->hwirq, lvl_type);
100 
101 	/* Propagate IRQ type setting to parent */
102 	if (type & IRQ_TYPE_EDGE_BOTH)
103 		return irq_chip_set_type_parent(d, IRQ_TYPE_EDGE_RISING);
104 	else
105 		return irq_chip_set_type_parent(d, IRQ_TYPE_LEVEL_HIGH);
106 }
107 
108 static void xgene_gpio_sb_irq_mask(struct irq_data *d)
109 {
110 	struct xgene_gpio_sb *priv = irq_data_get_irq_chip_data(d);
111 
112 	irq_chip_mask_parent(d);
113 
114 	gpiochip_disable_irq(&priv->chip.gc, d->hwirq);
115 }
116 
117 static void xgene_gpio_sb_irq_unmask(struct irq_data *d)
118 {
119 	struct xgene_gpio_sb *priv = irq_data_get_irq_chip_data(d);
120 
121 	gpiochip_enable_irq(&priv->chip.gc, d->hwirq);
122 
123 	irq_chip_unmask_parent(d);
124 }
125 
126 static const struct irq_chip xgene_gpio_sb_irq_chip = {
127 	.name           = "sbgpio",
128 	.irq_eoi	= irq_chip_eoi_parent,
129 	.irq_mask       = xgene_gpio_sb_irq_mask,
130 	.irq_unmask     = xgene_gpio_sb_irq_unmask,
131 	.irq_set_type   = xgene_gpio_sb_irq_set_type,
132 	.flags = IRQCHIP_IMMUTABLE,
133 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
134 };
135 
136 static int xgene_gpio_sb_to_irq(struct gpio_chip *gc, u32 gpio)
137 {
138 	struct xgene_gpio_sb *priv = gpiochip_get_data(gc);
139 	struct irq_fwspec fwspec;
140 
141 	if ((gpio < priv->irq_start) ||
142 			(gpio > HWIRQ_TO_GPIO(priv, priv->nirq)))
143 		return -ENXIO;
144 
145 	fwspec.fwnode = gc->parent->fwnode;
146 	fwspec.param_count = 2;
147 	fwspec.param[0] = GPIO_TO_HWIRQ(priv, gpio);
148 	fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
149 	return irq_create_fwspec_mapping(&fwspec);
150 }
151 
152 static int xgene_gpio_sb_domain_activate(struct irq_domain *d,
153 					 struct irq_data *irq_data,
154 					 bool reserve)
155 {
156 	struct xgene_gpio_sb *priv = d->host_data;
157 	u32 gpio = HWIRQ_TO_GPIO(priv, irq_data->hwirq);
158 	int ret;
159 
160 	ret = gpiochip_lock_as_irq(&priv->chip.gc, gpio);
161 	if (ret) {
162 		dev_err(priv->chip.gc.parent,
163 		"Unable to configure XGene GPIO standby pin %d as IRQ\n",
164 				gpio);
165 		return ret;
166 	}
167 
168 	xgene_gpio_set_bit(&priv->chip.gc, priv->regs + MPA_GPIO_SEL_LO,
169 			gpio * 2, 1);
170 	return 0;
171 }
172 
173 static void xgene_gpio_sb_domain_deactivate(struct irq_domain *d,
174 		struct irq_data *irq_data)
175 {
176 	struct xgene_gpio_sb *priv = d->host_data;
177 	u32 gpio = HWIRQ_TO_GPIO(priv, irq_data->hwirq);
178 
179 	gpiochip_unlock_as_irq(&priv->chip.gc, gpio);
180 	xgene_gpio_set_bit(&priv->chip.gc, priv->regs + MPA_GPIO_SEL_LO,
181 			gpio * 2, 0);
182 }
183 
184 static int xgene_gpio_sb_domain_translate(struct irq_domain *d,
185 		struct irq_fwspec *fwspec,
186 		unsigned long *hwirq,
187 		unsigned int *type)
188 {
189 	struct xgene_gpio_sb *priv = d->host_data;
190 
191 	if ((fwspec->param_count != 2) ||
192 		(fwspec->param[0] >= priv->nirq))
193 		return -EINVAL;
194 	*hwirq = fwspec->param[0];
195 	*type = fwspec->param[1];
196 	return 0;
197 }
198 
199 static int xgene_gpio_sb_domain_alloc(struct irq_domain *domain,
200 					unsigned int virq,
201 					unsigned int nr_irqs, void *data)
202 {
203 	struct irq_fwspec *fwspec = data;
204 	struct irq_fwspec parent_fwspec;
205 	struct xgene_gpio_sb *priv = domain->host_data;
206 	irq_hw_number_t hwirq;
207 	unsigned int i;
208 
209 	hwirq = fwspec->param[0];
210 	for (i = 0; i < nr_irqs; i++)
211 		irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
212 				&xgene_gpio_sb_irq_chip, priv);
213 
214 	parent_fwspec.fwnode = domain->parent->fwnode;
215 	if (is_of_node(parent_fwspec.fwnode)) {
216 		parent_fwspec.param_count = 3;
217 		parent_fwspec.param[0] = 0;/* SPI */
218 		/* Skip SGIs and PPIs*/
219 		parent_fwspec.param[1] = hwirq + priv->parent_irq_base - 32;
220 		parent_fwspec.param[2] = fwspec->param[1];
221 	} else if (is_fwnode_irqchip(parent_fwspec.fwnode)) {
222 		parent_fwspec.param_count = 2;
223 		parent_fwspec.param[0] = hwirq + priv->parent_irq_base;
224 		parent_fwspec.param[1] = fwspec->param[1];
225 	} else
226 		return -EINVAL;
227 
228 	return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
229 			&parent_fwspec);
230 }
231 
232 static const struct irq_domain_ops xgene_gpio_sb_domain_ops = {
233 	.translate      = xgene_gpio_sb_domain_translate,
234 	.alloc          = xgene_gpio_sb_domain_alloc,
235 	.free           = irq_domain_free_irqs_common,
236 	.activate	= xgene_gpio_sb_domain_activate,
237 	.deactivate	= xgene_gpio_sb_domain_deactivate,
238 };
239 
240 static int xgene_gpio_sb_probe(struct platform_device *pdev)
241 {
242 	struct gpio_generic_chip_config config;
243 	struct xgene_gpio_sb *priv;
244 	int ret;
245 	void __iomem *regs;
246 	struct irq_domain *parent_domain = NULL;
247 	u32 val32;
248 
249 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
250 	if (!priv)
251 		return -ENOMEM;
252 
253 	regs = devm_platform_ioremap_resource(pdev, 0);
254 	if (IS_ERR(regs))
255 		return PTR_ERR(regs);
256 
257 	priv->regs = regs;
258 
259 	ret = platform_get_irq(pdev, 0);
260 	if (ret > 0) {
261 		priv->parent_irq_base = irq_get_irq_data(ret)->hwirq;
262 		parent_domain = irq_get_irq_data(ret)->domain;
263 	}
264 	if (!parent_domain) {
265 		dev_err(&pdev->dev, "unable to obtain parent domain\n");
266 		return -ENODEV;
267 	}
268 
269 	config = (struct gpio_generic_chip_config) {
270 		.dev = &pdev->dev,
271 		.sz = 4,
272 		.dat = regs + MPA_GPIO_IN_ADDR,
273 		.set = regs + MPA_GPIO_OUT_ADDR,
274 		.dirout = regs + MPA_GPIO_OE_ADDR,
275 	};
276 
277 	ret = gpio_generic_chip_init(&priv->chip, &config);
278         if (ret)
279                 return ret;
280 
281 	priv->chip.gc.to_irq = xgene_gpio_sb_to_irq;
282 
283 	/* Retrieve start irq pin, use default if property not found */
284 	priv->irq_start = XGENE_DFLT_IRQ_START_PIN;
285 	if (!device_property_read_u32(&pdev->dev, "apm,irq-start", &val32))
286 		priv->irq_start = val32;
287 
288 	/* Retrieve number irqs, use default if property not found */
289 	priv->nirq = XGENE_DFLT_MAX_NIRQ;
290 	if (!device_property_read_u32(&pdev->dev, "apm,nr-irqs", &val32))
291 		priv->nirq = val32;
292 
293 	/* Retrieve number gpio, use default if property not found */
294 	priv->chip.gc.ngpio = XGENE_DFLT_MAX_NGPIO;
295 	if (!device_property_read_u32(&pdev->dev, "apm,nr-gpios", &val32))
296 		priv->chip.gc.ngpio = val32;
297 
298 	dev_info(&pdev->dev, "Support %d gpios, %d irqs start from pin %d\n",
299 			priv->chip.gc.ngpio, priv->nirq, priv->irq_start);
300 
301 	platform_set_drvdata(pdev, priv);
302 
303 	priv->irq_domain = irq_domain_create_hierarchy(parent_domain,
304 					0, priv->nirq, pdev->dev.fwnode,
305 					&xgene_gpio_sb_domain_ops, priv);
306 	if (!priv->irq_domain)
307 		return -ENODEV;
308 
309 	priv->chip.gc.irq.domain = priv->irq_domain;
310 
311 	ret = devm_gpiochip_add_data(&pdev->dev, &priv->chip.gc, priv);
312 	if (ret) {
313 		dev_err(&pdev->dev,
314 			"failed to register X-Gene GPIO Standby driver\n");
315 		irq_domain_remove(priv->irq_domain);
316 		return ret;
317 	}
318 
319 	dev_info(&pdev->dev, "X-Gene GPIO Standby driver registered\n");
320 
321 	/* Register interrupt handlers for GPIO signaled ACPI Events */
322 	acpi_gpiochip_request_interrupts(&priv->chip.gc);
323 
324 	return ret;
325 }
326 
327 static void xgene_gpio_sb_remove(struct platform_device *pdev)
328 {
329 	struct xgene_gpio_sb *priv = platform_get_drvdata(pdev);
330 
331 	acpi_gpiochip_free_interrupts(&priv->chip.gc);
332 
333 	irq_domain_remove(priv->irq_domain);
334 }
335 
336 static const struct of_device_id xgene_gpio_sb_of_match[] = {
337 	{ .compatible = "apm,xgene-gpio-sb" },
338 	{}
339 };
340 MODULE_DEVICE_TABLE(of, xgene_gpio_sb_of_match);
341 
342 static const struct acpi_device_id xgene_gpio_sb_acpi_match[] = {
343 	{ "APMC0D15" },
344 	{}
345 };
346 MODULE_DEVICE_TABLE(acpi, xgene_gpio_sb_acpi_match);
347 
348 static struct platform_driver xgene_gpio_sb_driver = {
349 	.driver = {
350 		   .name = "xgene-gpio-sb",
351 		   .of_match_table = xgene_gpio_sb_of_match,
352 		   .acpi_match_table = xgene_gpio_sb_acpi_match,
353 	},
354 	.probe = xgene_gpio_sb_probe,
355 	.remove = xgene_gpio_sb_remove,
356 };
357 module_platform_driver(xgene_gpio_sb_driver);
358 
359 MODULE_AUTHOR("AppliedMicro");
360 MODULE_DESCRIPTION("APM X-Gene GPIO Standby driver");
361 MODULE_LICENSE("GPL");
362