Linux 3.1.1
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / arch / avr32 / mach-at32ap / pio.c
blob9b39dea6682f83de9f81561ab6619299ede26c2e
1 /*
2 * Atmel PIO2 Port Multiplexer support
4 * Copyright (C) 2004-2006 Atmel Corporation
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 */
11 #include <linux/clk.h>
12 #include <linux/debugfs.h>
13 #include <linux/fs.h>
14 #include <linux/platform_device.h>
15 #include <linux/irq.h>
17 #include <asm/gpio.h>
18 #include <asm/io.h>
20 #include <mach/portmux.h>
22 #include "pio.h"
24 #define MAX_NR_PIO_DEVICES 8
26 struct pio_device {
27 struct gpio_chip chip;
28 void __iomem *regs;
29 const struct platform_device *pdev;
30 struct clk *clk;
31 u32 pinmux_mask;
32 char name[8];
35 static struct pio_device pio_dev[MAX_NR_PIO_DEVICES];
37 static struct pio_device *gpio_to_pio(unsigned int gpio)
39 struct pio_device *pio;
40 unsigned int index;
42 index = gpio >> 5;
43 if (index >= MAX_NR_PIO_DEVICES)
44 return NULL;
45 pio = &pio_dev[index];
46 if (!pio->regs)
47 return NULL;
49 return pio;
52 /* Pin multiplexing API */
53 static DEFINE_SPINLOCK(pio_lock);
55 void __init at32_select_periph(unsigned int port, u32 pin_mask,
56 unsigned int periph, unsigned long flags)
58 struct pio_device *pio;
60 /* assign and verify pio */
61 pio = gpio_to_pio(port);
62 if (unlikely(!pio)) {
63 printk(KERN_WARNING "pio: invalid port %u\n", port);
64 goto fail;
67 /* Test if any of the requested pins is already muxed */
68 spin_lock(&pio_lock);
69 if (unlikely(pio->pinmux_mask & pin_mask)) {
70 printk(KERN_WARNING "%s: pin(s) busy (requested 0x%x, busy 0x%x)\n",
71 pio->name, pin_mask, pio->pinmux_mask & pin_mask);
72 spin_unlock(&pio_lock);
73 goto fail;
76 pio->pinmux_mask |= pin_mask;
78 /* enable pull ups */
79 pio_writel(pio, PUER, pin_mask);
81 /* select either peripheral A or B */
82 if (periph)
83 pio_writel(pio, BSR, pin_mask);
84 else
85 pio_writel(pio, ASR, pin_mask);
87 /* enable peripheral control */
88 pio_writel(pio, PDR, pin_mask);
90 /* Disable pull ups if not requested. */
91 if (!(flags & AT32_GPIOF_PULLUP))
92 pio_writel(pio, PUDR, pin_mask);
94 spin_unlock(&pio_lock);
96 return;
98 fail:
99 dump_stack();
102 void __init at32_select_gpio(unsigned int pin, unsigned long flags)
104 struct pio_device *pio;
105 unsigned int pin_index = pin & 0x1f;
106 u32 mask = 1 << pin_index;
108 pio = gpio_to_pio(pin);
109 if (unlikely(!pio)) {
110 printk("pio: invalid pin %u\n", pin);
111 goto fail;
114 if (unlikely(test_and_set_bit(pin_index, &pio->pinmux_mask))) {
115 printk("%s: pin %u is busy\n", pio->name, pin_index);
116 goto fail;
119 if (flags & AT32_GPIOF_OUTPUT) {
120 if (flags & AT32_GPIOF_HIGH)
121 pio_writel(pio, SODR, mask);
122 else
123 pio_writel(pio, CODR, mask);
124 if (flags & AT32_GPIOF_MULTIDRV)
125 pio_writel(pio, MDER, mask);
126 else
127 pio_writel(pio, MDDR, mask);
128 pio_writel(pio, PUDR, mask);
129 pio_writel(pio, OER, mask);
130 } else {
131 if (flags & AT32_GPIOF_PULLUP)
132 pio_writel(pio, PUER, mask);
133 else
134 pio_writel(pio, PUDR, mask);
135 if (flags & AT32_GPIOF_DEGLITCH)
136 pio_writel(pio, IFER, mask);
137 else
138 pio_writel(pio, IFDR, mask);
139 pio_writel(pio, ODR, mask);
142 pio_writel(pio, PER, mask);
144 return;
146 fail:
147 dump_stack();
151 * Undo a previous pin reservation. Will not affect the hardware
152 * configuration.
154 void at32_deselect_pin(unsigned int pin)
156 struct pio_device *pio;
157 unsigned int pin_index = pin & 0x1f;
159 pio = gpio_to_pio(pin);
160 if (unlikely(!pio)) {
161 printk("pio: invalid pin %u\n", pin);
162 dump_stack();
163 return;
166 clear_bit(pin_index, &pio->pinmux_mask);
169 /* Reserve a pin, preventing anyone else from changing its configuration. */
170 void __init at32_reserve_pin(unsigned int port, u32 pin_mask)
172 struct pio_device *pio;
174 /* assign and verify pio */
175 pio = gpio_to_pio(port);
176 if (unlikely(!pio)) {
177 printk(KERN_WARNING "pio: invalid port %u\n", port);
178 goto fail;
181 /* Test if any of the requested pins is already muxed */
182 spin_lock(&pio_lock);
183 if (unlikely(pio->pinmux_mask & pin_mask)) {
184 printk(KERN_WARNING "%s: pin(s) busy (req. 0x%x, busy 0x%x)\n",
185 pio->name, pin_mask, pio->pinmux_mask & pin_mask);
186 spin_unlock(&pio_lock);
187 goto fail;
190 /* Reserve pins */
191 pio->pinmux_mask |= pin_mask;
192 spin_unlock(&pio_lock);
193 return;
195 fail:
196 dump_stack();
199 /*--------------------------------------------------------------------------*/
201 /* GPIO API */
203 static int direction_input(struct gpio_chip *chip, unsigned offset)
205 struct pio_device *pio = container_of(chip, struct pio_device, chip);
206 u32 mask = 1 << offset;
208 if (!(pio_readl(pio, PSR) & mask))
209 return -EINVAL;
211 pio_writel(pio, ODR, mask);
212 return 0;
215 static int gpio_get(struct gpio_chip *chip, unsigned offset)
217 struct pio_device *pio = container_of(chip, struct pio_device, chip);
219 return (pio_readl(pio, PDSR) >> offset) & 1;
222 static void gpio_set(struct gpio_chip *chip, unsigned offset, int value);
224 static int direction_output(struct gpio_chip *chip, unsigned offset, int value)
226 struct pio_device *pio = container_of(chip, struct pio_device, chip);
227 u32 mask = 1 << offset;
229 if (!(pio_readl(pio, PSR) & mask))
230 return -EINVAL;
232 gpio_set(chip, offset, value);
233 pio_writel(pio, OER, mask);
234 return 0;
237 static void gpio_set(struct gpio_chip *chip, unsigned offset, int value)
239 struct pio_device *pio = container_of(chip, struct pio_device, chip);
240 u32 mask = 1 << offset;
242 if (value)
243 pio_writel(pio, SODR, mask);
244 else
245 pio_writel(pio, CODR, mask);
248 /*--------------------------------------------------------------------------*/
250 /* GPIO IRQ support */
252 static void gpio_irq_mask(struct irq_data *d)
254 unsigned gpio = irq_to_gpio(d->irq);
255 struct pio_device *pio = &pio_dev[gpio >> 5];
257 pio_writel(pio, IDR, 1 << (gpio & 0x1f));
260 static void gpio_irq_unmask(struct irq_data *d)
262 unsigned gpio = irq_to_gpio(d->irq);
263 struct pio_device *pio = &pio_dev[gpio >> 5];
265 pio_writel(pio, IER, 1 << (gpio & 0x1f));
268 static int gpio_irq_type(struct irq_data *d, unsigned type)
270 if (type != IRQ_TYPE_EDGE_BOTH && type != IRQ_TYPE_NONE)
271 return -EINVAL;
273 return 0;
276 static struct irq_chip gpio_irqchip = {
277 .name = "gpio",
278 .irq_mask = gpio_irq_mask,
279 .irq_unmask = gpio_irq_unmask,
280 .irq_set_type = gpio_irq_type,
283 static void gpio_irq_handler(unsigned irq, struct irq_desc *desc)
285 struct pio_device *pio = irq_desc_get_chip_data(desc);
286 unsigned gpio_irq;
288 gpio_irq = (unsigned) irq_get_handler_data(irq);
289 for (;;) {
290 u32 isr;
292 /* ack pending GPIO interrupts */
293 isr = pio_readl(pio, ISR) & pio_readl(pio, IMR);
294 if (!isr)
295 break;
296 do {
297 int i;
299 i = ffs(isr) - 1;
300 isr &= ~(1 << i);
302 i += gpio_irq;
303 generic_handle_irq(i);
304 } while (isr);
308 static void __init
309 gpio_irq_setup(struct pio_device *pio, int irq, int gpio_irq)
311 unsigned i;
313 irq_set_chip_data(irq, pio);
314 irq_set_handler_data(irq, (void *)gpio_irq);
316 for (i = 0; i < 32; i++, gpio_irq++) {
317 irq_set_chip_data(gpio_irq, pio);
318 irq_set_chip_and_handler(gpio_irq, &gpio_irqchip,
319 handle_simple_irq);
322 irq_set_chained_handler(irq, gpio_irq_handler);
325 /*--------------------------------------------------------------------------*/
327 #ifdef CONFIG_DEBUG_FS
329 #include <linux/seq_file.h>
332 * This shows more info than the generic gpio dump code:
333 * pullups, deglitching, open drain drive.
335 static void pio_bank_show(struct seq_file *s, struct gpio_chip *chip)
337 struct pio_device *pio = container_of(chip, struct pio_device, chip);
338 u32 psr, osr, imr, pdsr, pusr, ifsr, mdsr;
339 unsigned i;
340 u32 mask;
341 char bank;
343 psr = pio_readl(pio, PSR);
344 osr = pio_readl(pio, OSR);
345 imr = pio_readl(pio, IMR);
346 pdsr = pio_readl(pio, PDSR);
347 pusr = pio_readl(pio, PUSR);
348 ifsr = pio_readl(pio, IFSR);
349 mdsr = pio_readl(pio, MDSR);
351 bank = 'A' + pio->pdev->id;
353 for (i = 0, mask = 1; i < 32; i++, mask <<= 1) {
354 const char *label;
356 label = gpiochip_is_requested(chip, i);
357 if (!label && (imr & mask))
358 label = "[irq]";
359 if (!label)
360 continue;
362 seq_printf(s, " gpio-%-3d P%c%-2d (%-12s) %s %s %s",
363 chip->base + i, bank, i,
364 label,
365 (osr & mask) ? "out" : "in ",
366 (mask & pdsr) ? "hi" : "lo",
367 (mask & pusr) ? " " : "up");
368 if (ifsr & mask)
369 seq_printf(s, " deglitch");
370 if ((osr & mdsr) & mask)
371 seq_printf(s, " open-drain");
372 if (imr & mask)
373 seq_printf(s, " irq-%d edge-both",
374 gpio_to_irq(chip->base + i));
375 seq_printf(s, "\n");
379 #else
380 #define pio_bank_show NULL
381 #endif
384 /*--------------------------------------------------------------------------*/
386 static int __init pio_probe(struct platform_device *pdev)
388 struct pio_device *pio = NULL;
389 int irq = platform_get_irq(pdev, 0);
390 int gpio_irq_base = GPIO_IRQ_BASE + pdev->id * 32;
392 BUG_ON(pdev->id >= MAX_NR_PIO_DEVICES);
393 pio = &pio_dev[pdev->id];
394 BUG_ON(!pio->regs);
396 pio->chip.label = pio->name;
397 pio->chip.base = pdev->id * 32;
398 pio->chip.ngpio = 32;
399 pio->chip.dev = &pdev->dev;
400 pio->chip.owner = THIS_MODULE;
402 pio->chip.direction_input = direction_input;
403 pio->chip.get = gpio_get;
404 pio->chip.direction_output = direction_output;
405 pio->chip.set = gpio_set;
406 pio->chip.dbg_show = pio_bank_show;
408 gpiochip_add(&pio->chip);
410 gpio_irq_setup(pio, irq, gpio_irq_base);
412 platform_set_drvdata(pdev, pio);
414 printk(KERN_DEBUG "%s: base 0x%p, irq %d chains %d..%d\n",
415 pio->name, pio->regs, irq, gpio_irq_base, gpio_irq_base + 31);
417 return 0;
420 static struct platform_driver pio_driver = {
421 .driver = {
422 .name = "pio",
426 static int __init pio_init(void)
428 return platform_driver_probe(&pio_driver, pio_probe);
430 postcore_initcall(pio_init);
432 void __init at32_init_pio(struct platform_device *pdev)
434 struct resource *regs;
435 struct pio_device *pio;
437 if (pdev->id > MAX_NR_PIO_DEVICES) {
438 dev_err(&pdev->dev, "only %d PIO devices supported\n",
439 MAX_NR_PIO_DEVICES);
440 return;
443 pio = &pio_dev[pdev->id];
444 snprintf(pio->name, sizeof(pio->name), "pio%d", pdev->id);
446 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
447 if (!regs) {
448 dev_err(&pdev->dev, "no mmio resource defined\n");
449 return;
452 pio->clk = clk_get(&pdev->dev, "mck");
453 if (IS_ERR(pio->clk))
455 * This is a fatal error, but if we continue we might
456 * be so lucky that we manage to initialize the
457 * console and display this message...
459 dev_err(&pdev->dev, "no mck clock defined\n");
460 else
461 clk_enable(pio->clk);
463 pio->pdev = pdev;
464 pio->regs = ioremap(regs->start, resource_size(regs));
466 /* start with irqs disabled and acked */
467 pio_writel(pio, IDR, ~0UL);
468 (void) pio_readl(pio, ISR);