1 /*
2 * Renesas IRQC Driver
3 *
4 * Copyright (C) 2013 Magnus Damm
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19
20 #include <linux/init.h>
21 #include <linux/platform_device.h>
22 #include <linux/spinlock.h>
23 #include <linux/interrupt.h>
24 #include <linux/ioport.h>
25 #include <linux/io.h>
26 #include <linux/irq.h>
27 #include <linux/irqdomain.h>
28 #include <linux/err.h>
29 #include <linux/slab.h>
30 #include <linux/module.h>
31 #include <linux/pm_runtime.h>
32
33 #define IRQC_IRQ_MAX 32 /* maximum 32 interrupts per driver instance */
34
35 #define IRQC_REQ_STS 0x00 /* Interrupt Request Status Register */
36 #define IRQC_EN_STS 0x04 /* Interrupt Enable Status Register */
37 #define IRQC_EN_SET 0x08 /* Interrupt Enable Set Register */
38 #define IRQC_INT_CPU_BASE(n) (0x000 + ((n) * 0x10))
39 /* SYS-CPU vs. RT-CPU */
40 #define DETECT_STATUS 0x100 /* IRQn Detect Status Register */
41 #define MONITOR 0x104 /* IRQn Signal Level Monitor Register */
42 #define HLVL_STS 0x108 /* IRQn High Level Detect Status Register */
43 #define LLVL_STS 0x10c /* IRQn Low Level Detect Status Register */
44 #define S_R_EDGE_STS 0x110 /* IRQn Sync Rising Edge Detect Status Reg. */
45 #define S_F_EDGE_STS 0x114 /* IRQn Sync Falling Edge Detect Status Reg. */
46 #define A_R_EDGE_STS 0x118 /* IRQn Async Rising Edge Detect Status Reg. */
47 #define A_F_EDGE_STS 0x11c /* IRQn Async Falling Edge Detect Status Reg. */
48 #define CHTEN_STS 0x120 /* Chattering Reduction Status Register */
49 #define IRQC_CONFIG(n) (0x180 + ((n) * 0x04))
50 /* IRQn Configuration Register */
51
52 struct irqc_irq {
53 int hw_irq;
54 int requested_irq;
55 struct irqc_priv *p;
56 };
57
58 struct irqc_priv {
59 void __iomem *iomem;
60 void __iomem *cpu_int_base;
61 struct irqc_irq irq[IRQC_IRQ_MAX];
62 unsigned int number_of_irqs;
63 struct platform_device *pdev;
64 struct irq_chip_generic *gc;
65 struct irq_domain *irq_domain;
66 atomic_t wakeup_path;
67 };
68
irq_data_to_priv(struct irq_data * data)69 static struct irqc_priv *irq_data_to_priv(struct irq_data *data)
70 {
71 return data->domain->host_data;
72 }
73
irqc_dbg(struct irqc_irq * i,char * str)74 static void irqc_dbg(struct irqc_irq *i, char *str)
75 {
76 dev_dbg(&i->p->pdev->dev, "%s (%d:%d)\n",
77 str, i->requested_irq, i->hw_irq);
78 }
79
80 static unsigned char irqc_sense[IRQ_TYPE_SENSE_MASK + 1] = {
81 [IRQ_TYPE_LEVEL_LOW] = 0x01,
82 [IRQ_TYPE_LEVEL_HIGH] = 0x02,
83 [IRQ_TYPE_EDGE_FALLING] = 0x04, /* Synchronous */
84 [IRQ_TYPE_EDGE_RISING] = 0x08, /* Synchronous */
85 [IRQ_TYPE_EDGE_BOTH] = 0x0c, /* Synchronous */
86 };
87
irqc_irq_set_type(struct irq_data * d,unsigned int type)88 static int irqc_irq_set_type(struct irq_data *d, unsigned int type)
89 {
90 struct irqc_priv *p = irq_data_to_priv(d);
91 int hw_irq = irqd_to_hwirq(d);
92 unsigned char value = irqc_sense[type & IRQ_TYPE_SENSE_MASK];
93 u32 tmp;
94
95 irqc_dbg(&p->irq[hw_irq], "sense");
96
97 if (!value)
98 return -EINVAL;
99
100 tmp = ioread32(p->iomem + IRQC_CONFIG(hw_irq));
101 tmp &= ~0x3f;
102 tmp |= value;
103 iowrite32(tmp, p->iomem + IRQC_CONFIG(hw_irq));
104 return 0;
105 }
106
irqc_irq_set_wake(struct irq_data * d,unsigned int on)107 static int irqc_irq_set_wake(struct irq_data *d, unsigned int on)
108 {
109 struct irqc_priv *p = irq_data_to_priv(d);
110 int hw_irq = irqd_to_hwirq(d);
111
112 irq_set_irq_wake(p->irq[hw_irq].requested_irq, on);
113 if (on)
114 atomic_inc(&p->wakeup_path);
115 else
116 atomic_dec(&p->wakeup_path);
117
118 return 0;
119 }
120
irqc_irq_handler(int irq,void * dev_id)121 static irqreturn_t irqc_irq_handler(int irq, void *dev_id)
122 {
123 struct irqc_irq *i = dev_id;
124 struct irqc_priv *p = i->p;
125 u32 bit = BIT(i->hw_irq);
126
127 irqc_dbg(i, "demux1");
128
129 if (ioread32(p->iomem + DETECT_STATUS) & bit) {
130 iowrite32(bit, p->iomem + DETECT_STATUS);
131 irqc_dbg(i, "demux2");
132 generic_handle_irq(irq_find_mapping(p->irq_domain, i->hw_irq));
133 return IRQ_HANDLED;
134 }
135 return IRQ_NONE;
136 }
137
irqc_probe(struct platform_device * pdev)138 static int irqc_probe(struct platform_device *pdev)
139 {
140 struct irqc_priv *p;
141 struct resource *io;
142 struct resource *irq;
143 const char *name = dev_name(&pdev->dev);
144 int ret;
145 int k;
146
147 p = kzalloc(sizeof(*p), GFP_KERNEL);
148 if (!p) {
149 dev_err(&pdev->dev, "failed to allocate driver data\n");
150 ret = -ENOMEM;
151 goto err0;
152 }
153
154 p->pdev = pdev;
155 platform_set_drvdata(pdev, p);
156
157 pm_runtime_enable(&pdev->dev);
158 pm_runtime_get_sync(&pdev->dev);
159
160 /* get hold of manadatory IOMEM */
161 io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
162 if (!io) {
163 dev_err(&pdev->dev, "not enough IOMEM resources\n");
164 ret = -EINVAL;
165 goto err1;
166 }
167
168 /* allow any number of IRQs between 1 and IRQC_IRQ_MAX */
169 for (k = 0; k < IRQC_IRQ_MAX; k++) {
170 irq = platform_get_resource(pdev, IORESOURCE_IRQ, k);
171 if (!irq)
172 break;
173
174 p->irq[k].p = p;
175 p->irq[k].hw_irq = k;
176 p->irq[k].requested_irq = irq->start;
177 }
178
179 p->number_of_irqs = k;
180 if (p->number_of_irqs < 1) {
181 dev_err(&pdev->dev, "not enough IRQ resources\n");
182 ret = -EINVAL;
183 goto err1;
184 }
185
186 /* ioremap IOMEM and setup read/write callbacks */
187 p->iomem = ioremap_nocache(io->start, resource_size(io));
188 if (!p->iomem) {
189 dev_err(&pdev->dev, "failed to remap IOMEM\n");
190 ret = -ENXIO;
191 goto err2;
192 }
193
194 p->cpu_int_base = p->iomem + IRQC_INT_CPU_BASE(0); /* SYS-SPI */
195
196 p->irq_domain = irq_domain_add_linear(pdev->dev.of_node,
197 p->number_of_irqs,
198 &irq_generic_chip_ops, p);
199 if (!p->irq_domain) {
200 ret = -ENXIO;
201 dev_err(&pdev->dev, "cannot initialize irq domain\n");
202 goto err2;
203 }
204
205 ret = irq_alloc_domain_generic_chips(p->irq_domain, p->number_of_irqs,
206 1, name, handle_level_irq,
207 0, 0, IRQ_GC_INIT_NESTED_LOCK);
208 if (ret) {
209 dev_err(&pdev->dev, "cannot allocate generic chip\n");
210 goto err3;
211 }
212
213 p->gc = irq_get_domain_generic_chip(p->irq_domain, 0);
214 p->gc->reg_base = p->cpu_int_base;
215 p->gc->chip_types[0].regs.enable = IRQC_EN_SET;
216 p->gc->chip_types[0].regs.disable = IRQC_EN_STS;
217 p->gc->chip_types[0].chip.irq_mask = irq_gc_mask_disable_reg;
218 p->gc->chip_types[0].chip.irq_unmask = irq_gc_unmask_enable_reg;
219 p->gc->chip_types[0].chip.irq_set_type = irqc_irq_set_type;
220 p->gc->chip_types[0].chip.irq_set_wake = irqc_irq_set_wake;
221 p->gc->chip_types[0].chip.flags = IRQCHIP_MASK_ON_SUSPEND;
222
223 /* request interrupts one by one */
224 for (k = 0; k < p->number_of_irqs; k++) {
225 if (request_irq(p->irq[k].requested_irq, irqc_irq_handler,
226 0, name, &p->irq[k])) {
227 dev_err(&pdev->dev, "failed to request IRQ\n");
228 ret = -ENOENT;
229 goto err4;
230 }
231 }
232
233 dev_info(&pdev->dev, "driving %d irqs\n", p->number_of_irqs);
234
235 return 0;
236 err4:
237 while (--k >= 0)
238 free_irq(p->irq[k].requested_irq, &p->irq[k]);
239
240 err3:
241 irq_domain_remove(p->irq_domain);
242 err2:
243 iounmap(p->iomem);
244 err1:
245 pm_runtime_put(&pdev->dev);
246 pm_runtime_disable(&pdev->dev);
247 kfree(p);
248 err0:
249 return ret;
250 }
251
irqc_remove(struct platform_device * pdev)252 static int irqc_remove(struct platform_device *pdev)
253 {
254 struct irqc_priv *p = platform_get_drvdata(pdev);
255 int k;
256
257 for (k = 0; k < p->number_of_irqs; k++)
258 free_irq(p->irq[k].requested_irq, &p->irq[k]);
259
260 irq_domain_remove(p->irq_domain);
261 iounmap(p->iomem);
262 pm_runtime_put(&pdev->dev);
263 pm_runtime_disable(&pdev->dev);
264 kfree(p);
265 return 0;
266 }
267
irqc_suspend(struct device * dev)268 static int __maybe_unused irqc_suspend(struct device *dev)
269 {
270 struct irqc_priv *p = dev_get_drvdata(dev);
271
272 if (atomic_read(&p->wakeup_path))
273 device_set_wakeup_path(dev);
274
275 return 0;
276 }
277
278 static SIMPLE_DEV_PM_OPS(irqc_pm_ops, irqc_suspend, NULL);
279
280 static const struct of_device_id irqc_dt_ids[] = {
281 { .compatible = "renesas,irqc", },
282 {},
283 };
284 MODULE_DEVICE_TABLE(of, irqc_dt_ids);
285
286 static struct platform_driver irqc_device_driver = {
287 .probe = irqc_probe,
288 .remove = irqc_remove,
289 .driver = {
290 .name = "renesas_irqc",
291 .of_match_table = irqc_dt_ids,
292 .pm = &irqc_pm_ops,
293 }
294 };
295
irqc_init(void)296 static int __init irqc_init(void)
297 {
298 return platform_driver_register(&irqc_device_driver);
299 }
300 postcore_initcall(irqc_init);
301
irqc_exit(void)302 static void __exit irqc_exit(void)
303 {
304 platform_driver_unregister(&irqc_device_driver);
305 }
306 module_exit(irqc_exit);
307
308 MODULE_AUTHOR("Magnus Damm");
309 MODULE_DESCRIPTION("Renesas IRQC Driver");
310 MODULE_LICENSE("GPL v2");
311