diff options
Diffstat (limited to 'drivers/gpio/gpio-sa1100.c')
-rw-r--r-- | drivers/gpio/gpio-sa1100.c | 328 |
1 files changed, 328 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-sa1100.c b/drivers/gpio/gpio-sa1100.c new file mode 100644 index 000000000..edff5e814 --- /dev/null +++ b/drivers/gpio/gpio-sa1100.c @@ -0,0 +1,328 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/arch/arm/mach-sa1100/gpio.c + * + * Generic SA-1100 GPIO handling + */ +#include <linux/gpio/driver.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/io.h> +#include <linux/syscore_ops.h> +#include <soc/sa1100/pwer.h> +#include <mach/hardware.h> +#include <mach/irqs.h> + +struct sa1100_gpio_chip { + struct gpio_chip chip; + void __iomem *membase; + int irqbase; + u32 irqmask; + u32 irqrising; + u32 irqfalling; + u32 irqwake; +}; + +#define sa1100_gpio_chip(x) container_of(x, struct sa1100_gpio_chip, chip) + +enum { + R_GPLR = 0x00, + R_GPDR = 0x04, + R_GPSR = 0x08, + R_GPCR = 0x0c, + R_GRER = 0x10, + R_GFER = 0x14, + R_GEDR = 0x18, + R_GAFR = 0x1c, +}; + +static int sa1100_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + return readl_relaxed(sa1100_gpio_chip(chip)->membase + R_GPLR) & + BIT(offset); +} + +static void sa1100_gpio_set(struct gpio_chip *chip, unsigned offset, int value) +{ + int reg = value ? R_GPSR : R_GPCR; + + writel_relaxed(BIT(offset), sa1100_gpio_chip(chip)->membase + reg); +} + +static int sa1100_get_direction(struct gpio_chip *chip, unsigned offset) +{ + void __iomem *gpdr = sa1100_gpio_chip(chip)->membase + R_GPDR; + + if (readl_relaxed(gpdr) & BIT(offset)) + return GPIO_LINE_DIRECTION_OUT; + + return GPIO_LINE_DIRECTION_IN; +} + +static int sa1100_direction_input(struct gpio_chip *chip, unsigned offset) +{ + void __iomem *gpdr = sa1100_gpio_chip(chip)->membase + R_GPDR; + unsigned long flags; + + local_irq_save(flags); + writel_relaxed(readl_relaxed(gpdr) & ~BIT(offset), gpdr); + local_irq_restore(flags); + + return 0; +} + +static int sa1100_direction_output(struct gpio_chip *chip, unsigned offset, int value) +{ + void __iomem *gpdr = sa1100_gpio_chip(chip)->membase + R_GPDR; + unsigned long flags; + + local_irq_save(flags); + sa1100_gpio_set(chip, offset, value); + writel_relaxed(readl_relaxed(gpdr) | BIT(offset), gpdr); + local_irq_restore(flags); + + return 0; +} + +static int sa1100_to_irq(struct gpio_chip *chip, unsigned offset) +{ + return sa1100_gpio_chip(chip)->irqbase + offset; +} + +static struct sa1100_gpio_chip sa1100_gpio_chip = { + .chip = { + .label = "gpio", + .get_direction = sa1100_get_direction, + .direction_input = sa1100_direction_input, + .direction_output = sa1100_direction_output, + .set = sa1100_gpio_set, + .get = sa1100_gpio_get, + .to_irq = sa1100_to_irq, + .base = 0, + .ngpio = GPIO_MAX + 1, + }, + .membase = (void *)&GPLR, + .irqbase = IRQ_GPIO0, +}; + +/* + * SA1100 GPIO edge detection for IRQs: + * IRQs are generated on Falling-Edge, Rising-Edge, or both. + * Use this instead of directly setting GRER/GFER. + */ +static void sa1100_update_edge_regs(struct sa1100_gpio_chip *sgc) +{ + void *base = sgc->membase; + u32 grer, gfer; + + grer = sgc->irqrising & sgc->irqmask; + gfer = sgc->irqfalling & sgc->irqmask; + + writel_relaxed(grer, base + R_GRER); + writel_relaxed(gfer, base + R_GFER); +} + +static int sa1100_gpio_type(struct irq_data *d, unsigned int type) +{ + struct sa1100_gpio_chip *sgc = irq_data_get_irq_chip_data(d); + unsigned int mask = BIT(d->hwirq); + + if (type == IRQ_TYPE_PROBE) { + if ((sgc->irqrising | sgc->irqfalling) & mask) + return 0; + type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING; + } + + if (type & IRQ_TYPE_EDGE_RISING) + sgc->irqrising |= mask; + else + sgc->irqrising &= ~mask; + if (type & IRQ_TYPE_EDGE_FALLING) + sgc->irqfalling |= mask; + else + sgc->irqfalling &= ~mask; + + sa1100_update_edge_regs(sgc); + + return 0; +} + +/* + * GPIO IRQs must be acknowledged. + */ +static void sa1100_gpio_ack(struct irq_data *d) +{ + struct sa1100_gpio_chip *sgc = irq_data_get_irq_chip_data(d); + + writel_relaxed(BIT(d->hwirq), sgc->membase + R_GEDR); +} + +static void sa1100_gpio_mask(struct irq_data *d) +{ + struct sa1100_gpio_chip *sgc = irq_data_get_irq_chip_data(d); + unsigned int mask = BIT(d->hwirq); + + sgc->irqmask &= ~mask; + + sa1100_update_edge_regs(sgc); +} + +static void sa1100_gpio_unmask(struct irq_data *d) +{ + struct sa1100_gpio_chip *sgc = irq_data_get_irq_chip_data(d); + unsigned int mask = BIT(d->hwirq); + + sgc->irqmask |= mask; + + sa1100_update_edge_regs(sgc); +} + +static int sa1100_gpio_wake(struct irq_data *d, unsigned int on) +{ + struct sa1100_gpio_chip *sgc = irq_data_get_irq_chip_data(d); + int ret = sa11x0_gpio_set_wake(d->hwirq, on); + if (!ret) { + if (on) + sgc->irqwake |= BIT(d->hwirq); + else + sgc->irqwake &= ~BIT(d->hwirq); + } + return ret; +} + +/* + * This is for GPIO IRQs + */ +static struct irq_chip sa1100_gpio_irq_chip = { + .name = "GPIO", + .irq_ack = sa1100_gpio_ack, + .irq_mask = sa1100_gpio_mask, + .irq_unmask = sa1100_gpio_unmask, + .irq_set_type = sa1100_gpio_type, + .irq_set_wake = sa1100_gpio_wake, +}; + +static int sa1100_gpio_irqdomain_map(struct irq_domain *d, + unsigned int irq, irq_hw_number_t hwirq) +{ + struct sa1100_gpio_chip *sgc = d->host_data; + + irq_set_chip_data(irq, sgc); + irq_set_chip_and_handler(irq, &sa1100_gpio_irq_chip, handle_edge_irq); + irq_set_probe(irq); + + return 0; +} + +static const struct irq_domain_ops sa1100_gpio_irqdomain_ops = { + .map = sa1100_gpio_irqdomain_map, + .xlate = irq_domain_xlate_onetwocell, +}; + +static struct irq_domain *sa1100_gpio_irqdomain; + +/* + * IRQ 0-11 (GPIO) handler. We enter here with the + * irq_controller_lock held, and IRQs disabled. Decode the IRQ + * and call the handler. + */ +static void sa1100_gpio_handler(struct irq_desc *desc) +{ + struct sa1100_gpio_chip *sgc = irq_desc_get_handler_data(desc); + unsigned int irq, mask; + void __iomem *gedr = sgc->membase + R_GEDR; + + mask = readl_relaxed(gedr); + do { + /* + * clear down all currently active IRQ sources. + * We will be processing them all. + */ + writel_relaxed(mask, gedr); + + irq = sgc->irqbase; + do { + if (mask & 1) + generic_handle_irq(irq); + mask >>= 1; + irq++; + } while (mask); + + mask = readl_relaxed(gedr); + } while (mask); +} + +static int sa1100_gpio_suspend(void) +{ + struct sa1100_gpio_chip *sgc = &sa1100_gpio_chip; + + /* + * Set the appropriate edges for wakeup. + */ + writel_relaxed(sgc->irqwake & sgc->irqrising, sgc->membase + R_GRER); + writel_relaxed(sgc->irqwake & sgc->irqfalling, sgc->membase + R_GFER); + + /* + * Clear any pending GPIO interrupts. + */ + writel_relaxed(readl_relaxed(sgc->membase + R_GEDR), + sgc->membase + R_GEDR); + + return 0; +} + +static void sa1100_gpio_resume(void) +{ + sa1100_update_edge_regs(&sa1100_gpio_chip); +} + +static struct syscore_ops sa1100_gpio_syscore_ops = { + .suspend = sa1100_gpio_suspend, + .resume = sa1100_gpio_resume, +}; + +static int __init sa1100_gpio_init_devicefs(void) +{ + register_syscore_ops(&sa1100_gpio_syscore_ops); + return 0; +} + +device_initcall(sa1100_gpio_init_devicefs); + +static const int sa1100_gpio_irqs[] __initconst = { + /* Install handlers for GPIO 0-10 edge detect interrupts */ + IRQ_GPIO0_SC, + IRQ_GPIO1_SC, + IRQ_GPIO2_SC, + IRQ_GPIO3_SC, + IRQ_GPIO4_SC, + IRQ_GPIO5_SC, + IRQ_GPIO6_SC, + IRQ_GPIO7_SC, + IRQ_GPIO8_SC, + IRQ_GPIO9_SC, + IRQ_GPIO10_SC, + /* Install handler for GPIO 11-27 edge detect interrupts */ + IRQ_GPIO11_27, +}; + +void __init sa1100_init_gpio(void) +{ + struct sa1100_gpio_chip *sgc = &sa1100_gpio_chip; + int i; + + /* clear all GPIO edge detects */ + writel_relaxed(0, sgc->membase + R_GFER); + writel_relaxed(0, sgc->membase + R_GRER); + writel_relaxed(-1, sgc->membase + R_GEDR); + + gpiochip_add_data(&sa1100_gpio_chip.chip, NULL); + + sa1100_gpio_irqdomain = irq_domain_add_simple(NULL, + 28, IRQ_GPIO0, + &sa1100_gpio_irqdomain_ops, sgc); + + for (i = 0; i < ARRAY_SIZE(sa1100_gpio_irqs); i++) + irq_set_chained_handler_and_data(sa1100_gpio_irqs[i], + sa1100_gpio_handler, sgc); +} |