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

source code of linux/drivers/gpio/gpio-xgene-sb.c