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Diffstat (limited to 'arch/arm/mach-pxa/gpio.c')
-rw-r--r--arch/arm/mach-pxa/gpio.c325
1 files changed, 271 insertions, 54 deletions
diff --git a/arch/arm/mach-pxa/gpio.c b/arch/arm/mach-pxa/gpio.c
index 8638dd7dd076..7d3e16970be0 100644
--- a/arch/arm/mach-pxa/gpio.c
+++ b/arch/arm/mach-pxa/gpio.c
@@ -14,11 +14,14 @@
#include <linux/init.h>
#include <linux/module.h>
+#include <linux/irq.h>
+#include <linux/sysdev.h>
#include <asm/gpio.h>
#include <asm/hardware.h>
#include <asm/io.h>
#include <asm/arch/pxa-regs.h>
+#include <asm/arch/pxa2xx-gpio.h>
#include "generic.h"
@@ -129,69 +132,283 @@ static void pxa_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
__raw_writel(mask, pxa->regbase + GPCR_OFFSET);
}
+#define GPIO_CHIP(_n) \
+ [_n] = { \
+ .regbase = GPIO##_n##_BASE, \
+ .chip = { \
+ .label = "gpio-" #_n, \
+ .direction_input = pxa_gpio_direction_input, \
+ .direction_output = pxa_gpio_direction_output, \
+ .get = pxa_gpio_get, \
+ .set = pxa_gpio_set, \
+ .base = (_n) * 32, \
+ .ngpio = 32, \
+ }, \
+ }
+
static struct pxa_gpio_chip pxa_gpio_chip[] = {
- [0] = {
- .regbase = GPIO0_BASE,
- .chip = {
- .label = "gpio-0",
- .direction_input = pxa_gpio_direction_input,
- .direction_output = pxa_gpio_direction_output,
- .get = pxa_gpio_get,
- .set = pxa_gpio_set,
- .base = 0,
- .ngpio = 32,
- },
- },
- [1] = {
- .regbase = GPIO1_BASE,
- .chip = {
- .label = "gpio-1",
- .direction_input = pxa_gpio_direction_input,
- .direction_output = pxa_gpio_direction_output,
- .get = pxa_gpio_get,
- .set = pxa_gpio_set,
- .base = 32,
- .ngpio = 32,
- },
- },
- [2] = {
- .regbase = GPIO2_BASE,
- .chip = {
- .label = "gpio-2",
- .direction_input = pxa_gpio_direction_input,
- .direction_output = pxa_gpio_direction_output,
- .get = pxa_gpio_get,
- .set = pxa_gpio_set,
- .base = 64,
- .ngpio = 32, /* 21 for PXA25x */
- },
- },
+ GPIO_CHIP(0),
+ GPIO_CHIP(1),
+ GPIO_CHIP(2),
#if defined(CONFIG_PXA27x) || defined(CONFIG_PXA3xx)
- [3] = {
- .regbase = GPIO3_BASE,
- .chip = {
- .label = "gpio-3",
- .direction_input = pxa_gpio_direction_input,
- .direction_output = pxa_gpio_direction_output,
- .get = pxa_gpio_get,
- .set = pxa_gpio_set,
- .base = 96,
- .ngpio = 32,
- },
- },
+ GPIO_CHIP(3),
#endif
};
-void __init pxa_init_gpio(int gpio_nr)
+/*
+ * PXA GPIO edge detection for IRQs:
+ * IRQs are generated on Falling-Edge, Rising-Edge, or both.
+ * Use this instead of directly setting GRER/GFER.
+ */
+
+static unsigned long GPIO_IRQ_rising_edge[4];
+static unsigned long GPIO_IRQ_falling_edge[4];
+static unsigned long GPIO_IRQ_mask[4];
+
+/*
+ * On PXA25x and PXA27x, GAFRx and GPDRx together decide the alternate
+ * function of a GPIO, and GPDRx cannot be altered once configured. It
+ * is attributed as "occupied" here (I know this terminology isn't
+ * accurate, you are welcome to propose a better one :-)
+ */
+static int __gpio_is_occupied(unsigned gpio)
+{
+ if (cpu_is_pxa25x() || cpu_is_pxa27x())
+ return GAFR(gpio) & (0x3 << (((gpio) & 0xf) * 2));
+ else
+ return 0;
+}
+
+static int pxa_gpio_irq_type(unsigned int irq, unsigned int type)
+{
+ int gpio, idx;
+
+ gpio = IRQ_TO_GPIO(irq);
+ idx = gpio >> 5;
+
+ if (type == IRQ_TYPE_PROBE) {
+ /* Don't mess with enabled GPIOs using preconfigured edges or
+ * GPIOs set to alternate function or to output during probe
+ */
+ if ((GPIO_IRQ_rising_edge[idx] |
+ GPIO_IRQ_falling_edge[idx] |
+ GPDR(gpio)) & GPIO_bit(gpio))
+ return 0;
+
+ if (__gpio_is_occupied(gpio))
+ return 0;
+
+ type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
+ }
+
+ GPDR(gpio) &= ~GPIO_bit(gpio);
+
+ if (type & IRQ_TYPE_EDGE_RISING)
+ __set_bit(gpio, GPIO_IRQ_rising_edge);
+ else
+ __clear_bit(gpio, GPIO_IRQ_rising_edge);
+
+ if (type & IRQ_TYPE_EDGE_FALLING)
+ __set_bit(gpio, GPIO_IRQ_falling_edge);
+ else
+ __clear_bit(gpio, GPIO_IRQ_falling_edge);
+
+ GRER(gpio) = GPIO_IRQ_rising_edge[idx] & GPIO_IRQ_mask[idx];
+ GFER(gpio) = GPIO_IRQ_falling_edge[idx] & GPIO_IRQ_mask[idx];
+
+ pr_debug("%s: IRQ%d (GPIO%d) - edge%s%s\n", __func__, irq, gpio,
+ ((type & IRQ_TYPE_EDGE_RISING) ? " rising" : ""),
+ ((type & IRQ_TYPE_EDGE_FALLING) ? " falling" : ""));
+ return 0;
+}
+
+/*
+ * GPIO IRQs must be acknowledged. This is for GPIO 0 and 1.
+ */
+
+static void pxa_ack_low_gpio(unsigned int irq)
+{
+ GEDR0 = (1 << (irq - IRQ_GPIO0));
+}
+
+static void pxa_mask_low_gpio(unsigned int irq)
+{
+ ICMR &= ~(1 << (irq - PXA_IRQ(0)));
+}
+
+static void pxa_unmask_low_gpio(unsigned int irq)
+{
+ ICMR |= 1 << (irq - PXA_IRQ(0));
+}
+
+static struct irq_chip pxa_low_gpio_chip = {
+ .name = "GPIO-l",
+ .ack = pxa_ack_low_gpio,
+ .mask = pxa_mask_low_gpio,
+ .unmask = pxa_unmask_low_gpio,
+ .set_type = pxa_gpio_irq_type,
+};
+
+/*
+ * Demux handler for GPIO>=2 edge detect interrupts
+ */
+
+#define GEDR_BITS (sizeof(gedr) * BITS_PER_BYTE)
+
+static void pxa_gpio_demux_handler(unsigned int irq, struct irq_desc *desc)
+{
+ int loop, bit, n;
+ unsigned long gedr[4];
+
+ do {
+ gedr[0] = GEDR0 & GPIO_IRQ_mask[0] & ~3;
+ gedr[1] = GEDR1 & GPIO_IRQ_mask[1];
+ gedr[2] = GEDR2 & GPIO_IRQ_mask[2];
+ gedr[3] = GEDR3 & GPIO_IRQ_mask[3];
+
+ GEDR0 = gedr[0]; GEDR1 = gedr[1];
+ GEDR2 = gedr[2]; GEDR3 = gedr[3];
+
+ loop = 0;
+ bit = find_first_bit(gedr, GEDR_BITS);
+ while (bit < GEDR_BITS) {
+ loop = 1;
+
+ n = PXA_GPIO_IRQ_BASE + bit;
+ desc_handle_irq(n, irq_desc + n);
+
+ bit = find_next_bit(gedr, GEDR_BITS, bit + 1);
+ }
+ } while (loop);
+}
+
+static void pxa_ack_muxed_gpio(unsigned int irq)
+{
+ int gpio = irq - IRQ_GPIO(2) + 2;
+ GEDR(gpio) = GPIO_bit(gpio);
+}
+
+static void pxa_mask_muxed_gpio(unsigned int irq)
+{
+ int gpio = irq - IRQ_GPIO(2) + 2;
+ __clear_bit(gpio, GPIO_IRQ_mask);
+ GRER(gpio) &= ~GPIO_bit(gpio);
+ GFER(gpio) &= ~GPIO_bit(gpio);
+}
+
+static void pxa_unmask_muxed_gpio(unsigned int irq)
+{
+ int gpio = irq - IRQ_GPIO(2) + 2;
+ int idx = gpio >> 5;
+ __set_bit(gpio, GPIO_IRQ_mask);
+ GRER(gpio) = GPIO_IRQ_rising_edge[idx] & GPIO_IRQ_mask[idx];
+ GFER(gpio) = GPIO_IRQ_falling_edge[idx] & GPIO_IRQ_mask[idx];
+}
+
+static struct irq_chip pxa_muxed_gpio_chip = {
+ .name = "GPIO",
+ .ack = pxa_ack_muxed_gpio,
+ .mask = pxa_mask_muxed_gpio,
+ .unmask = pxa_unmask_muxed_gpio,
+ .set_type = pxa_gpio_irq_type,
+};
+
+void __init pxa_init_gpio(int gpio_nr, set_wake_t fn)
{
- int i;
+ int irq, i, gpio;
+
+ pxa_last_gpio = gpio_nr - 1;
+
+ /* clear all GPIO edge detects */
+ for (i = 0; i < gpio_nr; i += 32) {
+ GFER(i) = 0;
+ GRER(i) = 0;
+ GEDR(i) = GEDR(i);
+ }
+
+ /* GPIO 0 and 1 must have their mask bit always set */
+ GPIO_IRQ_mask[0] = 3;
+
+ for (irq = IRQ_GPIO0; irq <= IRQ_GPIO1; irq++) {
+ set_irq_chip(irq, &pxa_low_gpio_chip);
+ set_irq_handler(irq, handle_edge_irq);
+ set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+ }
+
+ for (irq = IRQ_GPIO(2); irq < IRQ_GPIO(gpio_nr); irq++) {
+ set_irq_chip(irq, &pxa_muxed_gpio_chip);
+ set_irq_handler(irq, handle_edge_irq);
+ set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+ }
+
+ /* Install handler for GPIO>=2 edge detect interrupts */
+ set_irq_chained_handler(IRQ_GPIO_2_x, pxa_gpio_demux_handler);
+
+ pxa_low_gpio_chip.set_wake = fn;
+ pxa_muxed_gpio_chip.set_wake = fn;
/* add a GPIO chip for each register bank.
* the last PXA25x register only contains 21 GPIOs
*/
- for (i = 0; i < gpio_nr; i += 32) {
- if (i+32 > gpio_nr)
- pxa_gpio_chip[i/32].chip.ngpio = gpio_nr - i;
- gpiochip_add(&pxa_gpio_chip[i/32].chip);
+ for (gpio = 0, i = 0; gpio < gpio_nr; gpio += 32, i++) {
+ if (gpio + 32 > gpio_nr)
+ pxa_gpio_chip[i].chip.ngpio = gpio_nr - gpio;
+ gpiochip_add(&pxa_gpio_chip[i].chip);
}
}
+
+#ifdef CONFIG_PM
+
+static unsigned long saved_gplr[4];
+static unsigned long saved_gpdr[4];
+static unsigned long saved_grer[4];
+static unsigned long saved_gfer[4];
+
+static int pxa_gpio_suspend(struct sys_device *dev, pm_message_t state)
+{
+ int i, gpio;
+
+ for (gpio = 0, i = 0; gpio < pxa_last_gpio; gpio += 32, i++) {
+ saved_gplr[i] = GPLR(gpio);
+ saved_gpdr[i] = GPDR(gpio);
+ saved_grer[i] = GRER(gpio);
+ saved_gfer[i] = GFER(gpio);
+
+ /* Clear GPIO transition detect bits */
+ GEDR(gpio) = GEDR(gpio);
+ }
+ return 0;
+}
+
+static int pxa_gpio_resume(struct sys_device *dev)
+{
+ int i, gpio;
+
+ for (gpio = 0, i = 0; gpio < pxa_last_gpio; gpio += 32, i++) {
+ /* restore level with set/clear */
+ GPSR(gpio) = saved_gplr[i];
+ GPCR(gpio) = ~saved_gplr[i];
+
+ GRER(gpio) = saved_grer[i];
+ GFER(gpio) = saved_gfer[i];
+ GPDR(gpio) = saved_gpdr[i];
+ }
+ return 0;
+}
+#else
+#define pxa_gpio_suspend NULL
+#define pxa_gpio_resume NULL
+#endif
+
+struct sysdev_class pxa_gpio_sysclass = {
+ .name = "gpio",
+ .suspend = pxa_gpio_suspend,
+ .resume = pxa_gpio_resume,
+};
+
+static int __init pxa_gpio_init(void)
+{
+ return sysdev_class_register(&pxa_gpio_sysclass);
+}
+
+core_initcall(pxa_gpio_init);