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/platform_data/irq-renesas-irqc.h>
32
33 #define IRQC_IRQ_MAX 32 /* maximum 32 interrupts per driver instance */
34
35 #define IRQC_REQ_STS 0x00
36 #define IRQC_EN_STS 0x04
37 #define IRQC_EN_SET 0x08
38 #define IRQC_INT_CPU_BASE(n) (0x000 + ((n) * 0x10))
39 #define DETECT_STATUS 0x100
40 #define IRQC_CONFIG(n) (0x180 + ((n) * 0x04))
41
42 struct irqc_irq {
43 int hw_irq;
44 int requested_irq;
45 int domain_irq;
46 struct irqc_priv *p;
47 };
48
49 struct irqc_priv {
50 void __iomem *iomem;
51 void __iomem *cpu_int_base;
52 struct irqc_irq irq[IRQC_IRQ_MAX];
53 struct renesas_irqc_config config;
54 unsigned int number_of_irqs;
55 struct platform_device *pdev;
56 struct irq_chip irq_chip;
57 struct irq_domain *irq_domain;
58 };
59
irqc_dbg(struct irqc_irq * i,char * str)60 static void irqc_dbg(struct irqc_irq *i, char *str)
61 {
62 dev_dbg(&i->p->pdev->dev, "%s (%d:%d:%d)\n",
63 str, i->requested_irq, i->hw_irq, i->domain_irq);
64 }
65
irqc_irq_enable(struct irq_data * d)66 static void irqc_irq_enable(struct irq_data *d)
67 {
68 struct irqc_priv *p = irq_data_get_irq_chip_data(d);
69 int hw_irq = irqd_to_hwirq(d);
70
71 irqc_dbg(&p->irq[hw_irq], "enable");
72 iowrite32(BIT(hw_irq), p->cpu_int_base + IRQC_EN_SET);
73 }
74
irqc_irq_disable(struct irq_data * d)75 static void irqc_irq_disable(struct irq_data *d)
76 {
77 struct irqc_priv *p = irq_data_get_irq_chip_data(d);
78 int hw_irq = irqd_to_hwirq(d);
79
80 irqc_dbg(&p->irq[hw_irq], "disable");
81 iowrite32(BIT(hw_irq), p->cpu_int_base + IRQC_EN_STS);
82 }
83
84 #define INTC_IRQ_SENSE_VALID 0x10
85 #define INTC_IRQ_SENSE(x) (x + INTC_IRQ_SENSE_VALID)
86
87 static unsigned char irqc_sense[IRQ_TYPE_SENSE_MASK + 1] = {
88 [IRQ_TYPE_LEVEL_LOW] = INTC_IRQ_SENSE(0x01),
89 [IRQ_TYPE_LEVEL_HIGH] = INTC_IRQ_SENSE(0x02),
90 [IRQ_TYPE_EDGE_FALLING] = INTC_IRQ_SENSE(0x04), /* Synchronous */
91 [IRQ_TYPE_EDGE_RISING] = INTC_IRQ_SENSE(0x08), /* Synchronous */
92 [IRQ_TYPE_EDGE_BOTH] = INTC_IRQ_SENSE(0x0c), /* Synchronous */
93 };
94
irqc_irq_set_type(struct irq_data * d,unsigned int type)95 static int irqc_irq_set_type(struct irq_data *d, unsigned int type)
96 {
97 struct irqc_priv *p = irq_data_get_irq_chip_data(d);
98 int hw_irq = irqd_to_hwirq(d);
99 unsigned char value = irqc_sense[type & IRQ_TYPE_SENSE_MASK];
100 unsigned long tmp;
101
102 irqc_dbg(&p->irq[hw_irq], "sense");
103
104 if (!(value & INTC_IRQ_SENSE_VALID))
105 return -EINVAL;
106
107 tmp = ioread32(p->iomem + IRQC_CONFIG(hw_irq));
108 tmp &= ~0x3f;
109 tmp |= value ^ INTC_IRQ_SENSE_VALID;
110 iowrite32(tmp, p->iomem + IRQC_CONFIG(hw_irq));
111 return 0;
112 }
113
irqc_irq_handler(int irq,void * dev_id)114 static irqreturn_t irqc_irq_handler(int irq, void *dev_id)
115 {
116 struct irqc_irq *i = dev_id;
117 struct irqc_priv *p = i->p;
118 unsigned long bit = BIT(i->hw_irq);
119
120 irqc_dbg(i, "demux1");
121
122 if (ioread32(p->iomem + DETECT_STATUS) & bit) {
123 iowrite32(bit, p->iomem + DETECT_STATUS);
124 irqc_dbg(i, "demux2");
125 generic_handle_irq(i->domain_irq);
126 return IRQ_HANDLED;
127 }
128 return IRQ_NONE;
129 }
130
irqc_irq_domain_map(struct irq_domain * h,unsigned int virq,irq_hw_number_t hw)131 static int irqc_irq_domain_map(struct irq_domain *h, unsigned int virq,
132 irq_hw_number_t hw)
133 {
134 struct irqc_priv *p = h->host_data;
135
136 p->irq[hw].domain_irq = virq;
137 p->irq[hw].hw_irq = hw;
138
139 irqc_dbg(&p->irq[hw], "map");
140 irq_set_chip_data(virq, h->host_data);
141 irq_set_chip_and_handler(virq, &p->irq_chip, handle_level_irq);
142 set_irq_flags(virq, IRQF_VALID); /* kill me now */
143 return 0;
144 }
145
146 static struct irq_domain_ops irqc_irq_domain_ops = {
147 .map = irqc_irq_domain_map,
148 .xlate = irq_domain_xlate_twocell,
149 };
150
irqc_probe(struct platform_device * pdev)151 static int irqc_probe(struct platform_device *pdev)
152 {
153 struct renesas_irqc_config *pdata = pdev->dev.platform_data;
154 struct irqc_priv *p;
155 struct resource *io;
156 struct resource *irq;
157 struct irq_chip *irq_chip;
158 const char *name = dev_name(&pdev->dev);
159 int ret;
160 int k;
161
162 p = kzalloc(sizeof(*p), GFP_KERNEL);
163 if (!p) {
164 dev_err(&pdev->dev, "failed to allocate driver data\n");
165 ret = -ENOMEM;
166 goto err0;
167 }
168
169 /* deal with driver instance configuration */
170 if (pdata)
171 memcpy(&p->config, pdata, sizeof(*pdata));
172
173 p->pdev = pdev;
174 platform_set_drvdata(pdev, p);
175
176 /* get hold of manadatory IOMEM */
177 io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
178 if (!io) {
179 dev_err(&pdev->dev, "not enough IOMEM resources\n");
180 ret = -EINVAL;
181 goto err1;
182 }
183
184 /* allow any number of IRQs between 1 and IRQC_IRQ_MAX */
185 for (k = 0; k < IRQC_IRQ_MAX; k++) {
186 irq = platform_get_resource(pdev, IORESOURCE_IRQ, k);
187 if (!irq)
188 break;
189
190 p->irq[k].p = p;
191 p->irq[k].requested_irq = irq->start;
192 }
193
194 p->number_of_irqs = k;
195 if (p->number_of_irqs < 1) {
196 dev_err(&pdev->dev, "not enough IRQ resources\n");
197 ret = -EINVAL;
198 goto err1;
199 }
200
201 /* ioremap IOMEM and setup read/write callbacks */
202 p->iomem = ioremap_nocache(io->start, resource_size(io));
203 if (!p->iomem) {
204 dev_err(&pdev->dev, "failed to remap IOMEM\n");
205 ret = -ENXIO;
206 goto err2;
207 }
208
209 p->cpu_int_base = p->iomem + IRQC_INT_CPU_BASE(0); /* SYS-SPI */
210
211 irq_chip = &p->irq_chip;
212 irq_chip->name = name;
213 irq_chip->irq_mask = irqc_irq_disable;
214 irq_chip->irq_unmask = irqc_irq_enable;
215 irq_chip->irq_enable = irqc_irq_enable;
216 irq_chip->irq_disable = irqc_irq_disable;
217 irq_chip->irq_set_type = irqc_irq_set_type;
218 irq_chip->flags = IRQCHIP_SKIP_SET_WAKE;
219
220 p->irq_domain = irq_domain_add_simple(pdev->dev.of_node,
221 p->number_of_irqs,
222 p->config.irq_base,
223 &irqc_irq_domain_ops, p);
224 if (!p->irq_domain) {
225 ret = -ENXIO;
226 dev_err(&pdev->dev, "cannot initialize irq domain\n");
227 goto err2;
228 }
229
230 /* request interrupts one by one */
231 for (k = 0; k < p->number_of_irqs; k++) {
232 if (request_irq(p->irq[k].requested_irq, irqc_irq_handler,
233 0, name, &p->irq[k])) {
234 dev_err(&pdev->dev, "failed to request IRQ\n");
235 ret = -ENOENT;
236 goto err3;
237 }
238 }
239
240 dev_info(&pdev->dev, "driving %d irqs\n", p->number_of_irqs);
241
242 /* warn in case of mismatch if irq base is specified */
243 if (p->config.irq_base) {
244 if (p->config.irq_base != p->irq[0].domain_irq)
245 dev_warn(&pdev->dev, "irq base mismatch (%d/%d)\n",
246 p->config.irq_base, p->irq[0].domain_irq);
247 }
248
249 return 0;
250 err3:
251 for (; k >= 0; k--)
252 free_irq(p->irq[k - 1].requested_irq, &p->irq[k - 1]);
253
254 irq_domain_remove(p->irq_domain);
255 err2:
256 iounmap(p->iomem);
257 err1:
258 kfree(p);
259 err0:
260 return ret;
261 }
262
irqc_remove(struct platform_device * pdev)263 static int irqc_remove(struct platform_device *pdev)
264 {
265 struct irqc_priv *p = platform_get_drvdata(pdev);
266 int k;
267
268 for (k = 0; k < p->number_of_irqs; k++)
269 free_irq(p->irq[k].requested_irq, &p->irq[k]);
270
271 irq_domain_remove(p->irq_domain);
272 iounmap(p->iomem);
273 kfree(p);
274 return 0;
275 }
276
277 static const struct of_device_id irqc_dt_ids[] = {
278 { .compatible = "renesas,irqc", },
279 {},
280 };
281 MODULE_DEVICE_TABLE(of, irqc_dt_ids);
282
283 static struct platform_driver irqc_device_driver = {
284 .probe = irqc_probe,
285 .remove = irqc_remove,
286 .driver = {
287 .name = "renesas_irqc",
288 .of_match_table = irqc_dt_ids,
289 .owner = THIS_MODULE,
290 }
291 };
292
irqc_init(void)293 static int __init irqc_init(void)
294 {
295 return platform_driver_register(&irqc_device_driver);
296 }
297 postcore_initcall(irqc_init);
298
irqc_exit(void)299 static void __exit irqc_exit(void)
300 {
301 platform_driver_unregister(&irqc_device_driver);
302 }
303 module_exit(irqc_exit);
304
305 MODULE_AUTHOR("Magnus Damm");
306 MODULE_DESCRIPTION("Renesas IRQC Driver");
307 MODULE_LICENSE("GPL v2");
308