diff options
Diffstat (limited to 'arch/arm/mach-pxa/gpio.c')
-rw-r--r-- | arch/arm/mach-pxa/gpio.c | 325 |
1 files changed, 271 insertions, 54 deletions
diff --git a/arch/arm/mach-pxa/gpio.c b/arch/arm/mach-pxa/gpio.c index 8638dd7..7d3e169 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); |