1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Renesas IRQC Driver
4 *
5 * Copyright (C) 2013 Magnus Damm
6 */
7
8 #include <linux/init.h>
9 #include <linux/platform_device.h>
10 #include <linux/interrupt.h>
11 #include <linux/ioport.h>
12 #include <linux/io.h>
13 #include <linux/irq.h>
14 #include <linux/irqdomain.h>
15 #include <linux/err.h>
16 #include <linux/slab.h>
17 #include <linux/module.h>
18 #include <linux/pm_runtime.h>
19
20 #define IRQC_IRQ_MAX 32 /* maximum 32 interrupts per driver instance */
21
22 #define IRQC_REQ_STS 0x00 /* Interrupt Request Status Register */
23 #define IRQC_EN_STS 0x04 /* Interrupt Enable Status Register */
24 #define IRQC_EN_SET 0x08 /* Interrupt Enable Set Register */
25 #define IRQC_INT_CPU_BASE(n) (0x000 + ((n) * 0x10))
26 /* SYS-CPU vs. RT-CPU */
27 #define DETECT_STATUS 0x100 /* IRQn Detect Status Register */
28 #define MONITOR 0x104 /* IRQn Signal Level Monitor Register */
29 #define HLVL_STS 0x108 /* IRQn High Level Detect Status Register */
30 #define LLVL_STS 0x10c /* IRQn Low Level Detect Status Register */
31 #define S_R_EDGE_STS 0x110 /* IRQn Sync Rising Edge Detect Status Reg. */
32 #define S_F_EDGE_STS 0x114 /* IRQn Sync Falling Edge Detect Status Reg. */
33 #define A_R_EDGE_STS 0x118 /* IRQn Async Rising Edge Detect Status Reg. */
34 #define A_F_EDGE_STS 0x11c /* IRQn Async Falling Edge Detect Status Reg. */
35 #define CHTEN_STS 0x120 /* Chattering Reduction Status Register */
36 #define IRQC_CONFIG(n) (0x180 + ((n) * 0x04))
37 /* IRQn Configuration Register */
38
39 struct irqc_irq {
40 int hw_irq;
41 int requested_irq;
42 struct irqc_priv *p;
43 };
44
45 struct irqc_priv {
46 void __iomem *iomem;
47 void __iomem *cpu_int_base;
48 struct irqc_irq irq[IRQC_IRQ_MAX];
49 unsigned int number_of_irqs;
50 struct device *dev;
51 struct irq_chip_generic *gc;
52 struct irq_domain *irq_domain;
53 atomic_t wakeup_path;
54 };
55
irq_data_to_priv(struct irq_data * data)56 static struct irqc_priv *irq_data_to_priv(struct irq_data *data)
57 {
58 return data->domain->host_data;
59 }
60
irqc_dbg(struct irqc_irq * i,char * str)61 static void irqc_dbg(struct irqc_irq *i, char *str)
62 {
63 dev_dbg(i->p->dev, "%s (%d:%d)\n", str, i->requested_irq, i->hw_irq);
64 }
65
66 static unsigned char irqc_sense[IRQ_TYPE_SENSE_MASK + 1] = {
67 [IRQ_TYPE_LEVEL_LOW] = 0x01,
68 [IRQ_TYPE_LEVEL_HIGH] = 0x02,
69 [IRQ_TYPE_EDGE_FALLING] = 0x04, /* Synchronous */
70 [IRQ_TYPE_EDGE_RISING] = 0x08, /* Synchronous */
71 [IRQ_TYPE_EDGE_BOTH] = 0x0c, /* Synchronous */
72 };
73
irqc_irq_set_type(struct irq_data * d,unsigned int type)74 static int irqc_irq_set_type(struct irq_data *d, unsigned int type)
75 {
76 struct irqc_priv *p = irq_data_to_priv(d);
77 int hw_irq = irqd_to_hwirq(d);
78 unsigned char value = irqc_sense[type & IRQ_TYPE_SENSE_MASK];
79 u32 tmp;
80
81 irqc_dbg(&p->irq[hw_irq], "sense");
82
83 if (!value)
84 return -EINVAL;
85
86 tmp = ioread32(p->iomem + IRQC_CONFIG(hw_irq));
87 tmp &= ~0x3f;
88 tmp |= value;
89 iowrite32(tmp, p->iomem + IRQC_CONFIG(hw_irq));
90 return 0;
91 }
92
irqc_irq_set_wake(struct irq_data * d,unsigned int on)93 static int irqc_irq_set_wake(struct irq_data *d, unsigned int on)
94 {
95 struct irqc_priv *p = irq_data_to_priv(d);
96 int hw_irq = irqd_to_hwirq(d);
97
98 irq_set_irq_wake(p->irq[hw_irq].requested_irq, on);
99 if (on)
100 atomic_inc(&p->wakeup_path);
101 else
102 atomic_dec(&p->wakeup_path);
103
104 return 0;
105 }
106
irqc_irq_handler(int irq,void * dev_id)107 static irqreturn_t irqc_irq_handler(int irq, void *dev_id)
108 {
109 struct irqc_irq *i = dev_id;
110 struct irqc_priv *p = i->p;
111 u32 bit = BIT(i->hw_irq);
112
113 irqc_dbg(i, "demux1");
114
115 if (ioread32(p->iomem + DETECT_STATUS) & bit) {
116 iowrite32(bit, p->iomem + DETECT_STATUS);
117 irqc_dbg(i, "demux2");
118 generic_handle_irq(irq_find_mapping(p->irq_domain, i->hw_irq));
119 return IRQ_HANDLED;
120 }
121 return IRQ_NONE;
122 }
123
irqc_probe(struct platform_device * pdev)124 static int irqc_probe(struct platform_device *pdev)
125 {
126 struct device *dev = &pdev->dev;
127 const char *name = dev_name(dev);
128 struct irqc_priv *p;
129 struct resource *irq;
130 int ret;
131 int k;
132
133 p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL);
134 if (!p)
135 return -ENOMEM;
136
137 p->dev = dev;
138 platform_set_drvdata(pdev, p);
139
140 pm_runtime_enable(dev);
141 pm_runtime_get_sync(dev);
142
143 /* allow any number of IRQs between 1 and IRQC_IRQ_MAX */
144 for (k = 0; k < IRQC_IRQ_MAX; k++) {
145 irq = platform_get_resource(pdev, IORESOURCE_IRQ, k);
146 if (!irq)
147 break;
148
149 p->irq[k].p = p;
150 p->irq[k].hw_irq = k;
151 p->irq[k].requested_irq = irq->start;
152 }
153
154 p->number_of_irqs = k;
155 if (p->number_of_irqs < 1) {
156 dev_err(dev, "not enough IRQ resources\n");
157 ret = -EINVAL;
158 goto err_runtime_pm_disable;
159 }
160
161 /* ioremap IOMEM and setup read/write callbacks */
162 p->iomem = devm_platform_ioremap_resource(pdev, 0);
163 if (IS_ERR(p->iomem)) {
164 ret = PTR_ERR(p->iomem);
165 goto err_runtime_pm_disable;
166 }
167
168 p->cpu_int_base = p->iomem + IRQC_INT_CPU_BASE(0); /* SYS-SPI */
169
170 p->irq_domain = irq_domain_add_linear(dev->of_node, p->number_of_irqs,
171 &irq_generic_chip_ops, p);
172 if (!p->irq_domain) {
173 ret = -ENXIO;
174 dev_err(dev, "cannot initialize irq domain\n");
175 goto err_runtime_pm_disable;
176 }
177
178 ret = irq_alloc_domain_generic_chips(p->irq_domain, p->number_of_irqs,
179 1, "irqc", handle_level_irq,
180 0, 0, IRQ_GC_INIT_NESTED_LOCK);
181 if (ret) {
182 dev_err(dev, "cannot allocate generic chip\n");
183 goto err_remove_domain;
184 }
185
186 p->gc = irq_get_domain_generic_chip(p->irq_domain, 0);
187 p->gc->reg_base = p->cpu_int_base;
188 p->gc->chip_types[0].regs.enable = IRQC_EN_SET;
189 p->gc->chip_types[0].regs.disable = IRQC_EN_STS;
190 p->gc->chip_types[0].chip.parent_device = dev;
191 p->gc->chip_types[0].chip.irq_mask = irq_gc_mask_disable_reg;
192 p->gc->chip_types[0].chip.irq_unmask = irq_gc_unmask_enable_reg;
193 p->gc->chip_types[0].chip.irq_set_type = irqc_irq_set_type;
194 p->gc->chip_types[0].chip.irq_set_wake = irqc_irq_set_wake;
195 p->gc->chip_types[0].chip.flags = IRQCHIP_MASK_ON_SUSPEND;
196
197 /* request interrupts one by one */
198 for (k = 0; k < p->number_of_irqs; k++) {
199 if (devm_request_irq(dev, p->irq[k].requested_irq,
200 irqc_irq_handler, 0, name, &p->irq[k])) {
201 dev_err(dev, "failed to request IRQ\n");
202 ret = -ENOENT;
203 goto err_remove_domain;
204 }
205 }
206
207 dev_info(dev, "driving %d irqs\n", p->number_of_irqs);
208
209 return 0;
210
211 err_remove_domain:
212 irq_domain_remove(p->irq_domain);
213 err_runtime_pm_disable:
214 pm_runtime_put(dev);
215 pm_runtime_disable(dev);
216 return ret;
217 }
218
irqc_remove(struct platform_device * pdev)219 static int irqc_remove(struct platform_device *pdev)
220 {
221 struct irqc_priv *p = platform_get_drvdata(pdev);
222
223 irq_domain_remove(p->irq_domain);
224 pm_runtime_put(&pdev->dev);
225 pm_runtime_disable(&pdev->dev);
226 return 0;
227 }
228
irqc_suspend(struct device * dev)229 static int __maybe_unused irqc_suspend(struct device *dev)
230 {
231 struct irqc_priv *p = dev_get_drvdata(dev);
232
233 if (atomic_read(&p->wakeup_path))
234 device_set_wakeup_path(dev);
235
236 return 0;
237 }
238
239 static SIMPLE_DEV_PM_OPS(irqc_pm_ops, irqc_suspend, NULL);
240
241 static const struct of_device_id irqc_dt_ids[] = {
242 { .compatible = "renesas,irqc", },
243 {},
244 };
245 MODULE_DEVICE_TABLE(of, irqc_dt_ids);
246
247 static struct platform_driver irqc_device_driver = {
248 .probe = irqc_probe,
249 .remove = irqc_remove,
250 .driver = {
251 .name = "renesas_irqc",
252 .of_match_table = irqc_dt_ids,
253 .pm = &irqc_pm_ops,
254 }
255 };
256
irqc_init(void)257 static int __init irqc_init(void)
258 {
259 return platform_driver_register(&irqc_device_driver);
260 }
261 postcore_initcall(irqc_init);
262
irqc_exit(void)263 static void __exit irqc_exit(void)
264 {
265 platform_driver_unregister(&irqc_device_driver);
266 }
267 module_exit(irqc_exit);
268
269 MODULE_AUTHOR("Magnus Damm");
270 MODULE_DESCRIPTION("Renesas IRQC Driver");
271 MODULE_LICENSE("GPL v2");
272