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-rw-r--r--arch/arm/mach-nomadik/gpio.c396
1 files changed, 396 insertions, 0 deletions
diff --git a/arch/arm/mach-nomadik/gpio.c b/arch/arm/mach-nomadik/gpio.c
new file mode 100644
index 000000000000..9a09b2791e03
--- /dev/null
+++ b/arch/arm/mach-nomadik/gpio.c
@@ -0,0 +1,396 @@
1/*
2 * Generic GPIO driver for logic cells found in the Nomadik SoC
3 *
4 * Copyright (C) 2008,2009 STMicroelectronics
5 * Copyright (C) 2009 Alessandro Rubini <rubini@unipv.it>
6 * Rewritten based on work by Prafulla WADASKAR <prafulla.wadaskar@st.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/init.h>
15#include <linux/device.h>
16#include <linux/amba/bus.h>
17#include <linux/io.h>
18#include <linux/gpio.h>
19#include <linux/spinlock.h>
20#include <linux/interrupt.h>
21#include <linux/irq.h>
22
23#include <mach/hardware.h>
24#include <mach/gpio.h>
25
26/*
27 * The GPIO module in the Nomadik family of Systems-on-Chip is an
28 * AMBA device, managing 32 pins and alternate functions. The logic block
29 * is currently only used in the Nomadik.
30 *
31 * Symbols in this file are called "nmk_gpio" for "nomadik gpio"
32 */
33
34#define NMK_GPIO_PER_CHIP 32
35struct nmk_gpio_chip {
36 struct gpio_chip chip;
37 void __iomem *addr;
38 unsigned int parent_irq;
39 spinlock_t *lock;
40 /* Keep track of configured edges */
41 u32 edge_rising;
42 u32 edge_falling;
43};
44
45/* Mode functions */
46int nmk_gpio_set_mode(int gpio, int gpio_mode)
47{
48 struct nmk_gpio_chip *nmk_chip;
49 unsigned long flags;
50 u32 afunc, bfunc, bit;
51
52 nmk_chip = get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));
53 if (!nmk_chip)
54 return -EINVAL;
55
56 bit = 1 << (gpio - nmk_chip->chip.base);
57
58 spin_lock_irqsave(&nmk_chip->lock, flags);
59 afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & ~bit;
60 bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & ~bit;
61 if (gpio_mode & NMK_GPIO_ALT_A)
62 afunc |= bit;
63 if (gpio_mode & NMK_GPIO_ALT_B)
64 bfunc |= bit;
65 writel(afunc, nmk_chip->addr + NMK_GPIO_AFSLA);
66 writel(bfunc, nmk_chip->addr + NMK_GPIO_AFSLB);
67 spin_unlock_irqrestore(&nmk_chip->lock, flags);
68
69 return 0;
70}
71EXPORT_SYMBOL(nmk_gpio_set_mode);
72
73int nmk_gpio_get_mode(int gpio)
74{
75 struct nmk_gpio_chip *nmk_chip;
76 u32 afunc, bfunc, bit;
77
78 nmk_chip = get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));
79 if (!nmk_chip)
80 return -EINVAL;
81
82 bit = 1 << (gpio - nmk_chip->chip.base);
83
84 afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & bit;
85 bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & bit;
86
87 return (afunc ? NMK_GPIO_ALT_A : 0) | (bfunc ? NMK_GPIO_ALT_B : 0);
88}
89EXPORT_SYMBOL(nmk_gpio_get_mode);
90
91
92/* IRQ functions */
93static inline int nmk_gpio_get_bitmask(int gpio)
94{
95 return 1 << (gpio % 32);
96}
97
98static void nmk_gpio_irq_ack(unsigned int irq)
99{
100 int gpio;
101 struct nmk_gpio_chip *nmk_chip;
102
103 gpio = NOMADIK_IRQ_TO_GPIO(irq);
104 nmk_chip = get_irq_chip_data(irq);
105 if (!nmk_chip)
106 return;
107 writel(nmk_gpio_get_bitmask(gpio), nmk_chip->addr + NMK_GPIO_IC);
108}
109
110static void nmk_gpio_irq_mask(unsigned int irq)
111{
112 int gpio;
113 struct nmk_gpio_chip *nmk_chip;
114 unsigned long flags;
115 u32 bitmask, reg;
116
117 gpio = NOMADIK_IRQ_TO_GPIO(irq);
118 nmk_chip = get_irq_chip_data(irq);
119 bitmask = nmk_gpio_get_bitmask(gpio);
120 if (!nmk_chip)
121 return;
122
123 /* we must individually clear the two edges */
124 spin_lock_irqsave(&nmk_chip->lock, flags);
125 if (nmk_chip->edge_rising & bitmask) {
126 reg = readl(nmk_chip->addr + NMK_GPIO_RWIMSC);
127 reg &= ~bitmask;
128 writel(reg, nmk_chip->addr + NMK_GPIO_RWIMSC);
129 }
130 if (nmk_chip->edge_falling & bitmask) {
131 reg = readl(nmk_chip->addr + NMK_GPIO_FWIMSC);
132 reg &= ~bitmask;
133 writel(reg, nmk_chip->addr + NMK_GPIO_FWIMSC);
134 }
135 spin_unlock_irqrestore(&nmk_chip->lock, flags);
136};
137
138static void nmk_gpio_irq_unmask(unsigned int irq)
139{
140 int gpio;
141 struct nmk_gpio_chip *nmk_chip;
142 unsigned long flags;
143 u32 bitmask, reg;
144
145 gpio = NOMADIK_IRQ_TO_GPIO(irq);
146 nmk_chip = get_irq_chip_data(irq);
147 bitmask = nmk_gpio_get_bitmask(gpio);
148 if (!nmk_chip)
149 return;
150
151 /* we must individually set the two edges */
152 spin_lock_irqsave(&nmk_chip->lock, flags);
153 if (nmk_chip->edge_rising & bitmask) {
154 reg = readl(nmk_chip->addr + NMK_GPIO_RWIMSC);
155 reg |= bitmask;
156 writel(reg, nmk_chip->addr + NMK_GPIO_RWIMSC);
157 }
158 if (nmk_chip->edge_falling & bitmask) {
159 reg = readl(nmk_chip->addr + NMK_GPIO_FWIMSC);
160 reg |= bitmask;
161 writel(reg, nmk_chip->addr + NMK_GPIO_FWIMSC);
162 }
163 spin_unlock_irqrestore(&nmk_chip->lock, flags);
164}
165
166static int nmk_gpio_irq_set_type(unsigned int irq, unsigned int type)
167{
168 int gpio;
169 struct nmk_gpio_chip *nmk_chip;
170 unsigned long flags;
171 u32 bitmask;
172
173 gpio = NOMADIK_IRQ_TO_GPIO(irq);
174 nmk_chip = get_irq_chip_data(irq);
175 bitmask = nmk_gpio_get_bitmask(gpio);
176 if (!nmk_chip)
177 return -EINVAL;
178
179 if (type & IRQ_TYPE_LEVEL_HIGH)
180 return -EINVAL;
181 if (type & IRQ_TYPE_LEVEL_LOW)
182 return -EINVAL;
183
184 spin_lock_irqsave(&nmk_chip->lock, flags);
185
186 nmk_chip->edge_rising &= ~bitmask;
187 if (type & IRQ_TYPE_EDGE_RISING)
188 nmk_chip->edge_rising |= bitmask;
189 writel(nmk_chip->edge_rising, nmk_chip->addr + NMK_GPIO_RIMSC);
190
191 nmk_chip->edge_falling &= ~bitmask;
192 if (type & IRQ_TYPE_EDGE_FALLING)
193 nmk_chip->edge_falling |= bitmask;
194 writel(nmk_chip->edge_falling, nmk_chip->addr + NMK_GPIO_FIMSC);
195
196 spin_unlock_irqrestore(&nmk_chip->lock, flags);
197
198 nmk_gpio_irq_unmask(irq);
199
200 return 0;
201}
202
203static struct irq_chip nmk_gpio_irq_chip = {
204 .name = "Nomadik-GPIO",
205 .ack = nmk_gpio_irq_ack,
206 .mask = nmk_gpio_irq_mask,
207 .unmask = nmk_gpio_irq_unmask,
208 .set_type = nmk_gpio_irq_set_type,
209};
210
211static void nmk_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
212{
213 struct nmk_gpio_chip *nmk_chip;
214 struct irq_chip *host_chip;
215 unsigned int gpio_irq;
216 u32 pending;
217 unsigned int first_irq;
218
219 nmk_chip = get_irq_data(irq);
220 first_irq = NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base);
221 while ( (pending = readl(nmk_chip->addr + NMK_GPIO_IS)) ) {
222 gpio_irq = first_irq + __ffs(pending);
223 generic_handle_irq(gpio_irq);
224 }
225 if (0) {/* don't ack parent irq, as ack == disable */
226 host_chip = get_irq_chip(irq);
227 host_chip->ack(irq);
228 }
229}
230
231static int nmk_gpio_init_irq(struct nmk_gpio_chip *nmk_chip)
232{
233 unsigned int first_irq;
234 int i;
235
236 first_irq = NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base);
237 for (i = first_irq; i < first_irq + NMK_GPIO_PER_CHIP; i++) {
238 set_irq_chip(i, &nmk_gpio_irq_chip);
239 set_irq_handler(i, handle_edge_irq);
240 set_irq_flags(i, IRQF_VALID);
241 set_irq_chip_data(i, nmk_chip);
242 }
243 set_irq_chained_handler(nmk_chip->parent_irq, nmk_gpio_irq_handler);
244 set_irq_data(nmk_chip->parent_irq, nmk_chip);
245 return 0;
246}
247
248/* I/O Functions */
249static int nmk_gpio_make_input(struct gpio_chip *chip, unsigned offset)
250{
251 struct nmk_gpio_chip *nmk_chip =
252 container_of(chip, struct nmk_gpio_chip, chip);
253
254 writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRC);
255 return 0;
256}
257
258static int nmk_gpio_make_output(struct gpio_chip *chip, unsigned offset,
259 int val)
260{
261 struct nmk_gpio_chip *nmk_chip =
262 container_of(chip, struct nmk_gpio_chip, chip);
263
264 writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRS);
265 return 0;
266}
267
268static int nmk_gpio_get_input(struct gpio_chip *chip, unsigned offset)
269{
270 struct nmk_gpio_chip *nmk_chip =
271 container_of(chip, struct nmk_gpio_chip, chip);
272 u32 bit = 1 << offset;
273
274 return (readl(nmk_chip->addr + NMK_GPIO_DAT) & bit) != 0;
275}
276
277static void nmk_gpio_set_output(struct gpio_chip *chip, unsigned offset,
278 int val)
279{
280 struct nmk_gpio_chip *nmk_chip =
281 container_of(chip, struct nmk_gpio_chip, chip);
282 u32 bit = 1 << offset;
283
284 if (val)
285 writel(bit, nmk_chip->addr + NMK_GPIO_DATS);
286 else
287 writel(bit, nmk_chip->addr + NMK_GPIO_DATC);
288}
289
290/* This structure is replicated for each GPIO block allocated at probe time */
291static struct gpio_chip nmk_gpio_template = {
292 .direction_input = nmk_gpio_make_input,
293 .get = nmk_gpio_get_input,
294 .direction_output = nmk_gpio_make_output,
295 .set = nmk_gpio_set_output,
296 .ngpio = NMK_GPIO_PER_CHIP,
297 .can_sleep = 0,
298};
299
300static int __init nmk_gpio_probe(struct amba_device *dev, struct amba_id *id)
301{
302 struct nmk_gpio_platform_data *pdata;
303 struct nmk_gpio_chip *nmk_chip;
304 struct gpio_chip *chip;
305 int ret;
306
307 pdata = dev->dev.platform_data;
308 ret = amba_request_regions(dev, pdata->name);
309 if (ret)
310 return ret;
311
312 nmk_chip = kzalloc(sizeof(*nmk_chip), GFP_KERNEL);
313 if (!nmk_chip) {
314 ret = -ENOMEM;
315 goto out_amba;
316 }
317 /*
318 * The virt address in nmk_chip->addr is in the nomadik register space,
319 * so we can simply convert the resource address, without remapping
320 */
321 nmk_chip->addr = io_p2v(dev->res.start);
322 nmk_chip->chip = nmk_gpio_template;
323 nmk_chip->parent_irq = pdata->parent_irq;
324
325 chip = &nmk_chip->chip;
326 chip->base = pdata->first_gpio;
327 chip->label = pdata->name;
328 chip->dev = &dev->dev;
329 chip->owner = THIS_MODULE;
330
331 ret = gpiochip_add(&nmk_chip->chip);
332 if (ret)
333 goto out_free;
334
335 amba_set_drvdata(dev, nmk_chip);
336
337 nmk_gpio_init_irq(nmk_chip);
338
339 dev_info(&dev->dev, "Bits %i-%i at address %p\n",
340 nmk_chip->chip.base, nmk_chip->chip.base+31, nmk_chip->addr);
341 return 0;
342
343 out_free:
344 kfree(nmk_chip);
345 out_amba:
346 amba_release_regions(dev);
347 dev_err(&dev->dev, "Failure %i for GPIO %i-%i\n", ret,
348 pdata->first_gpio, pdata->first_gpio+31);
349 return ret;
350}
351
352static int nmk_gpio_remove(struct amba_device *dev)
353{
354 struct nmk_gpio_chip *nmk_chip;
355
356 nmk_chip = amba_get_drvdata(dev);
357 gpiochip_remove(&nmk_chip->chip);
358 kfree(nmk_chip);
359 amba_release_regions(dev);
360 return 0;
361}
362
363
364/* We have 0x1f080060 and 0x1f180060, accept both using the mask */
365static struct amba_id nmk_gpio_ids[] = {
366 {
367 .id = 0x1f080060,
368 .mask = 0xffefffff,
369 },
370 {0, 0},
371};
372
373static struct amba_driver nmk_gpio_driver = {
374 .drv = {
375 .owner = THIS_MODULE,
376 .name = "gpio",
377 },
378 .probe = nmk_gpio_probe,
379 .remove = nmk_gpio_remove,
380 .suspend = NULL, /* to be done */
381 .resume = NULL,
382 .id_table = nmk_gpio_ids,
383};
384
385static int __init nmk_gpio_init(void)
386{
387 return amba_driver_register(&nmk_gpio_driver);
388}
389
390arch_initcall(nmk_gpio_init);
391
392MODULE_AUTHOR("Prafulla WADASKAR and Alessandro Rubini");
393MODULE_DESCRIPTION("Nomadik GPIO Driver");
394MODULE_LICENSE("GPL");
395
396