1 /*
2 * linux/arch/arm/mach-sa1100/gpio.c
3 *
4 * Generic SA-1100 GPIO handling
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 version 2 as
8 * published by the Free Software Foundation.
9 */
10 #include <linux/gpio/driver.h>
11 #include <linux/init.h>
12 #include <linux/module.h>
13 #include <linux/io.h>
14 #include <linux/syscore_ops.h>
15 #include <soc/sa1100/pwer.h>
16 #include <mach/hardware.h>
17 #include <mach/irqs.h>
18
19 struct sa1100_gpio_chip {
20 struct gpio_chip chip;
21 void __iomem *membase;
22 int irqbase;
23 u32 irqmask;
24 u32 irqrising;
25 u32 irqfalling;
26 u32 irqwake;
27 };
28
29 #define sa1100_gpio_chip(x) container_of(x, struct sa1100_gpio_chip, chip)
30
31 enum {
32 R_GPLR = 0x00,
33 R_GPDR = 0x04,
34 R_GPSR = 0x08,
35 R_GPCR = 0x0c,
36 R_GRER = 0x10,
37 R_GFER = 0x14,
38 R_GEDR = 0x18,
39 R_GAFR = 0x1c,
40 };
41
sa1100_gpio_get(struct gpio_chip * chip,unsigned offset)42 static int sa1100_gpio_get(struct gpio_chip *chip, unsigned offset)
43 {
44 return readl_relaxed(sa1100_gpio_chip(chip)->membase + R_GPLR) &
45 BIT(offset);
46 }
47
sa1100_gpio_set(struct gpio_chip * chip,unsigned offset,int value)48 static void sa1100_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
49 {
50 int reg = value ? R_GPSR : R_GPCR;
51
52 writel_relaxed(BIT(offset), sa1100_gpio_chip(chip)->membase + reg);
53 }
54
sa1100_get_direction(struct gpio_chip * chip,unsigned offset)55 static int sa1100_get_direction(struct gpio_chip *chip, unsigned offset)
56 {
57 void __iomem *gpdr = sa1100_gpio_chip(chip)->membase + R_GPDR;
58
59 return !(readl_relaxed(gpdr) & BIT(offset));
60 }
61
sa1100_direction_input(struct gpio_chip * chip,unsigned offset)62 static int sa1100_direction_input(struct gpio_chip *chip, unsigned offset)
63 {
64 void __iomem *gpdr = sa1100_gpio_chip(chip)->membase + R_GPDR;
65 unsigned long flags;
66
67 local_irq_save(flags);
68 writel_relaxed(readl_relaxed(gpdr) & ~BIT(offset), gpdr);
69 local_irq_restore(flags);
70
71 return 0;
72 }
73
sa1100_direction_output(struct gpio_chip * chip,unsigned offset,int value)74 static int sa1100_direction_output(struct gpio_chip *chip, unsigned offset, int value)
75 {
76 void __iomem *gpdr = sa1100_gpio_chip(chip)->membase + R_GPDR;
77 unsigned long flags;
78
79 local_irq_save(flags);
80 sa1100_gpio_set(chip, offset, value);
81 writel_relaxed(readl_relaxed(gpdr) | BIT(offset), gpdr);
82 local_irq_restore(flags);
83
84 return 0;
85 }
86
sa1100_to_irq(struct gpio_chip * chip,unsigned offset)87 static int sa1100_to_irq(struct gpio_chip *chip, unsigned offset)
88 {
89 return sa1100_gpio_chip(chip)->irqbase + offset;
90 }
91
92 static struct sa1100_gpio_chip sa1100_gpio_chip = {
93 .chip = {
94 .label = "gpio",
95 .get_direction = sa1100_get_direction,
96 .direction_input = sa1100_direction_input,
97 .direction_output = sa1100_direction_output,
98 .set = sa1100_gpio_set,
99 .get = sa1100_gpio_get,
100 .to_irq = sa1100_to_irq,
101 .base = 0,
102 .ngpio = GPIO_MAX + 1,
103 },
104 .membase = (void *)&GPLR,
105 .irqbase = IRQ_GPIO0,
106 };
107
108 /*
109 * SA1100 GPIO edge detection for IRQs:
110 * IRQs are generated on Falling-Edge, Rising-Edge, or both.
111 * Use this instead of directly setting GRER/GFER.
112 */
sa1100_update_edge_regs(struct sa1100_gpio_chip * sgc)113 static void sa1100_update_edge_regs(struct sa1100_gpio_chip *sgc)
114 {
115 void *base = sgc->membase;
116 u32 grer, gfer;
117
118 grer = sgc->irqrising & sgc->irqmask;
119 gfer = sgc->irqfalling & sgc->irqmask;
120
121 writel_relaxed(grer, base + R_GRER);
122 writel_relaxed(gfer, base + R_GFER);
123 }
124
sa1100_gpio_type(struct irq_data * d,unsigned int type)125 static int sa1100_gpio_type(struct irq_data *d, unsigned int type)
126 {
127 struct sa1100_gpio_chip *sgc = irq_data_get_irq_chip_data(d);
128 unsigned int mask = BIT(d->hwirq);
129
130 if (type == IRQ_TYPE_PROBE) {
131 if ((sgc->irqrising | sgc->irqfalling) & mask)
132 return 0;
133 type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
134 }
135
136 if (type & IRQ_TYPE_EDGE_RISING)
137 sgc->irqrising |= mask;
138 else
139 sgc->irqrising &= ~mask;
140 if (type & IRQ_TYPE_EDGE_FALLING)
141 sgc->irqfalling |= mask;
142 else
143 sgc->irqfalling &= ~mask;
144
145 sa1100_update_edge_regs(sgc);
146
147 return 0;
148 }
149
150 /*
151 * GPIO IRQs must be acknowledged.
152 */
sa1100_gpio_ack(struct irq_data * d)153 static void sa1100_gpio_ack(struct irq_data *d)
154 {
155 struct sa1100_gpio_chip *sgc = irq_data_get_irq_chip_data(d);
156
157 writel_relaxed(BIT(d->hwirq), sgc->membase + R_GEDR);
158 }
159
sa1100_gpio_mask(struct irq_data * d)160 static void sa1100_gpio_mask(struct irq_data *d)
161 {
162 struct sa1100_gpio_chip *sgc = irq_data_get_irq_chip_data(d);
163 unsigned int mask = BIT(d->hwirq);
164
165 sgc->irqmask &= ~mask;
166
167 sa1100_update_edge_regs(sgc);
168 }
169
sa1100_gpio_unmask(struct irq_data * d)170 static void sa1100_gpio_unmask(struct irq_data *d)
171 {
172 struct sa1100_gpio_chip *sgc = irq_data_get_irq_chip_data(d);
173 unsigned int mask = BIT(d->hwirq);
174
175 sgc->irqmask |= mask;
176
177 sa1100_update_edge_regs(sgc);
178 }
179
sa1100_gpio_wake(struct irq_data * d,unsigned int on)180 static int sa1100_gpio_wake(struct irq_data *d, unsigned int on)
181 {
182 struct sa1100_gpio_chip *sgc = irq_data_get_irq_chip_data(d);
183 int ret = sa11x0_gpio_set_wake(d->hwirq, on);
184 if (!ret) {
185 if (on)
186 sgc->irqwake |= BIT(d->hwirq);
187 else
188 sgc->irqwake &= ~BIT(d->hwirq);
189 }
190 return ret;
191 }
192
193 /*
194 * This is for GPIO IRQs
195 */
196 static struct irq_chip sa1100_gpio_irq_chip = {
197 .name = "GPIO",
198 .irq_ack = sa1100_gpio_ack,
199 .irq_mask = sa1100_gpio_mask,
200 .irq_unmask = sa1100_gpio_unmask,
201 .irq_set_type = sa1100_gpio_type,
202 .irq_set_wake = sa1100_gpio_wake,
203 };
204
sa1100_gpio_irqdomain_map(struct irq_domain * d,unsigned int irq,irq_hw_number_t hwirq)205 static int sa1100_gpio_irqdomain_map(struct irq_domain *d,
206 unsigned int irq, irq_hw_number_t hwirq)
207 {
208 struct sa1100_gpio_chip *sgc = d->host_data;
209
210 irq_set_chip_data(irq, sgc);
211 irq_set_chip_and_handler(irq, &sa1100_gpio_irq_chip, handle_edge_irq);
212 irq_set_probe(irq);
213
214 return 0;
215 }
216
217 static const struct irq_domain_ops sa1100_gpio_irqdomain_ops = {
218 .map = sa1100_gpio_irqdomain_map,
219 .xlate = irq_domain_xlate_onetwocell,
220 };
221
222 static struct irq_domain *sa1100_gpio_irqdomain;
223
224 /*
225 * IRQ 0-11 (GPIO) handler. We enter here with the
226 * irq_controller_lock held, and IRQs disabled. Decode the IRQ
227 * and call the handler.
228 */
sa1100_gpio_handler(struct irq_desc * desc)229 static void sa1100_gpio_handler(struct irq_desc *desc)
230 {
231 struct sa1100_gpio_chip *sgc = irq_desc_get_handler_data(desc);
232 unsigned int irq, mask;
233 void __iomem *gedr = sgc->membase + R_GEDR;
234
235 mask = readl_relaxed(gedr);
236 do {
237 /*
238 * clear down all currently active IRQ sources.
239 * We will be processing them all.
240 */
241 writel_relaxed(mask, gedr);
242
243 irq = sgc->irqbase;
244 do {
245 if (mask & 1)
246 generic_handle_irq(irq);
247 mask >>= 1;
248 irq++;
249 } while (mask);
250
251 mask = readl_relaxed(gedr);
252 } while (mask);
253 }
254
sa1100_gpio_suspend(void)255 static int sa1100_gpio_suspend(void)
256 {
257 struct sa1100_gpio_chip *sgc = &sa1100_gpio_chip;
258
259 /*
260 * Set the appropriate edges for wakeup.
261 */
262 writel_relaxed(sgc->irqwake & sgc->irqrising, sgc->membase + R_GRER);
263 writel_relaxed(sgc->irqwake & sgc->irqfalling, sgc->membase + R_GFER);
264
265 /*
266 * Clear any pending GPIO interrupts.
267 */
268 writel_relaxed(readl_relaxed(sgc->membase + R_GEDR),
269 sgc->membase + R_GEDR);
270
271 return 0;
272 }
273
sa1100_gpio_resume(void)274 static void sa1100_gpio_resume(void)
275 {
276 sa1100_update_edge_regs(&sa1100_gpio_chip);
277 }
278
279 static struct syscore_ops sa1100_gpio_syscore_ops = {
280 .suspend = sa1100_gpio_suspend,
281 .resume = sa1100_gpio_resume,
282 };
283
sa1100_gpio_init_devicefs(void)284 static int __init sa1100_gpio_init_devicefs(void)
285 {
286 register_syscore_ops(&sa1100_gpio_syscore_ops);
287 return 0;
288 }
289
290 device_initcall(sa1100_gpio_init_devicefs);
291
292 static const int sa1100_gpio_irqs[] __initconst = {
293 /* Install handlers for GPIO 0-10 edge detect interrupts */
294 IRQ_GPIO0_SC,
295 IRQ_GPIO1_SC,
296 IRQ_GPIO2_SC,
297 IRQ_GPIO3_SC,
298 IRQ_GPIO4_SC,
299 IRQ_GPIO5_SC,
300 IRQ_GPIO6_SC,
301 IRQ_GPIO7_SC,
302 IRQ_GPIO8_SC,
303 IRQ_GPIO9_SC,
304 IRQ_GPIO10_SC,
305 /* Install handler for GPIO 11-27 edge detect interrupts */
306 IRQ_GPIO11_27,
307 };
308
sa1100_init_gpio(void)309 void __init sa1100_init_gpio(void)
310 {
311 struct sa1100_gpio_chip *sgc = &sa1100_gpio_chip;
312 int i;
313
314 /* clear all GPIO edge detects */
315 writel_relaxed(0, sgc->membase + R_GFER);
316 writel_relaxed(0, sgc->membase + R_GRER);
317 writel_relaxed(-1, sgc->membase + R_GEDR);
318
319 gpiochip_add_data(&sa1100_gpio_chip.chip, NULL);
320
321 sa1100_gpio_irqdomain = irq_domain_add_simple(NULL,
322 28, IRQ_GPIO0,
323 &sa1100_gpio_irqdomain_ops, sgc);
324
325 for (i = 0; i < ARRAY_SIZE(sa1100_gpio_irqs); i++)
326 irq_set_chained_handler_and_data(sa1100_gpio_irqs[i],
327 sa1100_gpio_handler, sgc);
328 }
329