2 * Generic GPIO driver for logic cells found in the Nomadik SoC
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>
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.
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/device.h>
16 #include <linux/platform_device.h>
18 #include <linux/gpio.h>
19 #include <linux/spinlock.h>
20 #include <linux/interrupt.h>
21 #include <linux/irq.h>
23 #include <mach/hardware.h>
24 #include <mach/gpio.h>
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.
31 * Symbols in this file are called "nmk_gpio" for "nomadik gpio"
34 #define NMK_GPIO_PER_CHIP 32
35 struct nmk_gpio_chip {
36 struct gpio_chip chip;
38 unsigned int parent_irq;
40 /* Keep track of configured edges */
46 int nmk_gpio_set_mode(int gpio, int gpio_mode)
48 struct nmk_gpio_chip *nmk_chip;
50 u32 afunc, bfunc, bit;
52 nmk_chip = get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));
56 bit = 1 << (gpio - nmk_chip->chip.base);
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)
63 if (gpio_mode & NMK_GPIO_ALT_B)
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);
71 EXPORT_SYMBOL(nmk_gpio_set_mode);
73 int nmk_gpio_get_mode(int gpio)
75 struct nmk_gpio_chip *nmk_chip;
76 u32 afunc, bfunc, bit;
78 nmk_chip = get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));
82 bit = 1 << (gpio - nmk_chip->chip.base);
84 afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & bit;
85 bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & bit;
87 return (afunc ? NMK_GPIO_ALT_A : 0) | (bfunc ? NMK_GPIO_ALT_B : 0);
89 EXPORT_SYMBOL(nmk_gpio_get_mode);
93 static inline int nmk_gpio_get_bitmask(int gpio)
95 return 1 << (gpio % 32);
98 static void nmk_gpio_irq_ack(unsigned int irq)
101 struct nmk_gpio_chip *nmk_chip;
103 gpio = NOMADIK_IRQ_TO_GPIO(irq);
104 nmk_chip = get_irq_chip_data(irq);
107 writel(nmk_gpio_get_bitmask(gpio), nmk_chip->addr + NMK_GPIO_IC);
110 static void __nmk_gpio_irq_modify(struct nmk_gpio_chip *nmk_chip,
111 int gpio, bool enable)
113 u32 bitmask = nmk_gpio_get_bitmask(gpio);
116 /* we must individually set/clear the two edges */
117 if (nmk_chip->edge_rising & bitmask) {
118 reg = readl(nmk_chip->addr + NMK_GPIO_RIMSC);
123 writel(reg, nmk_chip->addr + NMK_GPIO_RIMSC);
125 if (nmk_chip->edge_falling & bitmask) {
126 reg = readl(nmk_chip->addr + NMK_GPIO_FIMSC);
131 writel(reg, nmk_chip->addr + NMK_GPIO_FIMSC);
135 static void nmk_gpio_irq_modify(unsigned int irq, bool enable)
138 struct nmk_gpio_chip *nmk_chip;
142 gpio = NOMADIK_IRQ_TO_GPIO(irq);
143 nmk_chip = get_irq_chip_data(irq);
144 bitmask = nmk_gpio_get_bitmask(gpio);
148 spin_lock_irqsave(&nmk_chip->lock, flags);
149 __nmk_gpio_irq_modify(nmk_chip, gpio, enable);
150 spin_unlock_irqrestore(&nmk_chip->lock, flags);
153 static void nmk_gpio_irq_mask(unsigned int irq)
155 nmk_gpio_irq_modify(irq, false);
158 static void nmk_gpio_irq_unmask(unsigned int irq)
160 nmk_gpio_irq_modify(irq, true);
163 static int nmk_gpio_irq_set_type(unsigned int irq, unsigned int type)
165 bool enabled = !(irq_to_desc(irq)->status & IRQ_DISABLED);
167 struct nmk_gpio_chip *nmk_chip;
171 gpio = NOMADIK_IRQ_TO_GPIO(irq);
172 nmk_chip = get_irq_chip_data(irq);
173 bitmask = nmk_gpio_get_bitmask(gpio);
177 if (type & IRQ_TYPE_LEVEL_HIGH)
179 if (type & IRQ_TYPE_LEVEL_LOW)
182 spin_lock_irqsave(&nmk_chip->lock, flags);
185 __nmk_gpio_irq_modify(nmk_chip, gpio, false);
187 nmk_chip->edge_rising &= ~bitmask;
188 if (type & IRQ_TYPE_EDGE_RISING)
189 nmk_chip->edge_rising |= bitmask;
191 nmk_chip->edge_falling &= ~bitmask;
192 if (type & IRQ_TYPE_EDGE_FALLING)
193 nmk_chip->edge_falling |= bitmask;
196 __nmk_gpio_irq_modify(nmk_chip, gpio, true);
198 spin_unlock_irqrestore(&nmk_chip->lock, flags);
203 static 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,
211 static void nmk_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
213 struct nmk_gpio_chip *nmk_chip;
214 struct irq_chip *host_chip = get_irq_chip(irq);
215 unsigned int gpio_irq;
217 unsigned int first_irq;
219 if (host_chip->mask_ack)
220 host_chip->mask_ack(irq);
222 host_chip->mask(irq);
227 nmk_chip = get_irq_data(irq);
228 first_irq = NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base);
229 while ( (pending = readl(nmk_chip->addr + NMK_GPIO_IS)) ) {
230 gpio_irq = first_irq + __ffs(pending);
231 generic_handle_irq(gpio_irq);
234 host_chip->unmask(irq);
237 static int nmk_gpio_init_irq(struct nmk_gpio_chip *nmk_chip)
239 unsigned int first_irq;
242 first_irq = NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base);
243 for (i = first_irq; i < first_irq + NMK_GPIO_PER_CHIP; i++) {
244 set_irq_chip(i, &nmk_gpio_irq_chip);
245 set_irq_handler(i, handle_edge_irq);
246 set_irq_flags(i, IRQF_VALID);
247 set_irq_chip_data(i, nmk_chip);
249 set_irq_chained_handler(nmk_chip->parent_irq, nmk_gpio_irq_handler);
250 set_irq_data(nmk_chip->parent_irq, nmk_chip);
255 static int nmk_gpio_make_input(struct gpio_chip *chip, unsigned offset)
257 struct nmk_gpio_chip *nmk_chip =
258 container_of(chip, struct nmk_gpio_chip, chip);
260 writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRC);
264 static int nmk_gpio_make_output(struct gpio_chip *chip, unsigned offset,
267 struct nmk_gpio_chip *nmk_chip =
268 container_of(chip, struct nmk_gpio_chip, chip);
270 writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRS);
274 static int nmk_gpio_get_input(struct gpio_chip *chip, unsigned offset)
276 struct nmk_gpio_chip *nmk_chip =
277 container_of(chip, struct nmk_gpio_chip, chip);
278 u32 bit = 1 << offset;
280 return (readl(nmk_chip->addr + NMK_GPIO_DAT) & bit) != 0;
283 static void nmk_gpio_set_output(struct gpio_chip *chip, unsigned offset,
286 struct nmk_gpio_chip *nmk_chip =
287 container_of(chip, struct nmk_gpio_chip, chip);
288 u32 bit = 1 << offset;
291 writel(bit, nmk_chip->addr + NMK_GPIO_DATS);
293 writel(bit, nmk_chip->addr + NMK_GPIO_DATC);
296 /* This structure is replicated for each GPIO block allocated at probe time */
297 static struct gpio_chip nmk_gpio_template = {
298 .direction_input = nmk_gpio_make_input,
299 .get = nmk_gpio_get_input,
300 .direction_output = nmk_gpio_make_output,
301 .set = nmk_gpio_set_output,
302 .ngpio = NMK_GPIO_PER_CHIP,
306 static int __init nmk_gpio_probe(struct platform_device *dev)
308 struct nmk_gpio_platform_data *pdata = dev->dev.platform_data;
309 struct nmk_gpio_chip *nmk_chip;
310 struct gpio_chip *chip;
311 struct resource *res;
318 res = platform_get_resource(dev, IORESOURCE_MEM, 0);
324 irq = platform_get_irq(dev, 0);
330 if (request_mem_region(res->start, resource_size(res),
331 dev_name(&dev->dev)) == NULL) {
336 nmk_chip = kzalloc(sizeof(*nmk_chip), GFP_KERNEL);
342 * The virt address in nmk_chip->addr is in the nomadik register space,
343 * so we can simply convert the resource address, without remapping
345 nmk_chip->addr = io_p2v(res->start);
346 nmk_chip->chip = nmk_gpio_template;
347 nmk_chip->parent_irq = irq;
348 spin_lock_init(&nmk_chip->lock);
350 chip = &nmk_chip->chip;
351 chip->base = pdata->first_gpio;
352 chip->label = pdata->name;
353 chip->dev = &dev->dev;
354 chip->owner = THIS_MODULE;
356 ret = gpiochip_add(&nmk_chip->chip);
360 platform_set_drvdata(dev, nmk_chip);
362 nmk_gpio_init_irq(nmk_chip);
364 dev_info(&dev->dev, "Bits %i-%i at address %p\n",
365 nmk_chip->chip.base, nmk_chip->chip.base+31, nmk_chip->addr);
371 release_mem_region(res->start, resource_size(res));
373 dev_err(&dev->dev, "Failure %i for GPIO %i-%i\n", ret,
374 pdata->first_gpio, pdata->first_gpio+31);
378 static int __exit nmk_gpio_remove(struct platform_device *dev)
380 struct nmk_gpio_chip *nmk_chip;
381 struct resource *res;
383 res = platform_get_resource(dev, IORESOURCE_MEM, 0);
385 nmk_chip = platform_get_drvdata(dev);
386 gpiochip_remove(&nmk_chip->chip);
388 release_mem_region(res->start, resource_size(res));
393 static struct platform_driver nmk_gpio_driver = {
395 .owner = THIS_MODULE,
398 .probe = nmk_gpio_probe,
399 .remove = __exit_p(nmk_gpio_remove),
400 .suspend = NULL, /* to be done */
404 static int __init nmk_gpio_init(void)
406 return platform_driver_register(&nmk_gpio_driver);
409 arch_initcall(nmk_gpio_init);
411 MODULE_AUTHOR("Prafulla WADASKAR and Alessandro Rubini");
412 MODULE_DESCRIPTION("Nomadik GPIO Driver");
413 MODULE_LICENSE("GPL");