diff options
Diffstat (limited to 'drivers/gpio/gpio-rda.c')
| -rw-r--r-- | drivers/gpio/gpio-rda.c | 292 |
1 files changed, 292 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-rda.c b/drivers/gpio/gpio-rda.c new file mode 100644 index 0000000000..cb2f63eee2 --- /dev/null +++ b/drivers/gpio/gpio-rda.c @@ -0,0 +1,292 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * RDA Micro GPIO driver + * + * Copyright (C) 2012 RDA Micro Inc. + * Copyright (C) 2019 Manivannan Sadhasivam + */ + +#include <linux/bitops.h> +#include <linux/gpio/driver.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/spinlock.h> + +#define RDA_GPIO_OEN_VAL 0x00 +#define RDA_GPIO_OEN_SET_OUT 0x04 +#define RDA_GPIO_OEN_SET_IN 0x08 +#define RDA_GPIO_VAL 0x0c +#define RDA_GPIO_SET 0x10 +#define RDA_GPIO_CLR 0x14 +#define RDA_GPIO_INT_CTRL_SET 0x18 +#define RDA_GPIO_INT_CTRL_CLR 0x1c +#define RDA_GPIO_INT_CLR 0x20 +#define RDA_GPIO_INT_STATUS 0x24 + +#define RDA_GPIO_IRQ_RISE_SHIFT 0 +#define RDA_GPIO_IRQ_FALL_SHIFT 8 +#define RDA_GPIO_DEBOUCE_SHIFT 16 +#define RDA_GPIO_LEVEL_SHIFT 24 + +#define RDA_GPIO_IRQ_MASK 0xff + +/* Each bank consists of 32 GPIOs */ +#define RDA_GPIO_BANK_NR 32 + +struct rda_gpio { + struct gpio_chip chip; + void __iomem *base; + spinlock_t lock; + int irq; +}; + +static inline void rda_gpio_update(struct gpio_chip *chip, unsigned int offset, + u16 reg, int val) +{ + struct rda_gpio *rda_gpio = gpiochip_get_data(chip); + void __iomem *base = rda_gpio->base; + unsigned long flags; + u32 tmp; + + spin_lock_irqsave(&rda_gpio->lock, flags); + tmp = readl_relaxed(base + reg); + + if (val) + tmp |= BIT(offset); + else + tmp &= ~BIT(offset); + + writel_relaxed(tmp, base + reg); + spin_unlock_irqrestore(&rda_gpio->lock, flags); +} + +static void rda_gpio_irq_mask(struct irq_data *data) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + struct rda_gpio *rda_gpio = gpiochip_get_data(chip); + void __iomem *base = rda_gpio->base; + u32 offset = irqd_to_hwirq(data); + u32 value; + + value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT; + value |= BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT; + + writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR); + gpiochip_disable_irq(chip, offset); +} + +static void rda_gpio_irq_ack(struct irq_data *data) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + u32 offset = irqd_to_hwirq(data); + + rda_gpio_update(chip, offset, RDA_GPIO_INT_CLR, 1); +} + +static int rda_gpio_set_irq(struct gpio_chip *chip, u32 offset, + unsigned int flow_type) +{ + struct rda_gpio *rda_gpio = gpiochip_get_data(chip); + void __iomem *base = rda_gpio->base; + u32 value; + + switch (flow_type) { + case IRQ_TYPE_EDGE_RISING: + /* Set rising edge trigger */ + value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT; + writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET); + + /* Switch to edge trigger interrupt */ + value = BIT(offset) << RDA_GPIO_LEVEL_SHIFT; + writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR); + break; + + case IRQ_TYPE_EDGE_FALLING: + /* Set falling edge trigger */ + value = BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT; + writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET); + + /* Switch to edge trigger interrupt */ + value = BIT(offset) << RDA_GPIO_LEVEL_SHIFT; + writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR); + break; + + case IRQ_TYPE_EDGE_BOTH: + /* Set both edge trigger */ + value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT; + value |= BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT; + writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET); + + /* Switch to edge trigger interrupt */ + value = BIT(offset) << RDA_GPIO_LEVEL_SHIFT; + writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR); + break; + + case IRQ_TYPE_LEVEL_HIGH: + /* Set high level trigger */ + value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT; + + /* Switch to level trigger interrupt */ + value |= BIT(offset) << RDA_GPIO_LEVEL_SHIFT; + writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET); + break; + + case IRQ_TYPE_LEVEL_LOW: + /* Set low level trigger */ + value = BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT; + + /* Switch to level trigger interrupt */ + value |= BIT(offset) << RDA_GPIO_LEVEL_SHIFT; + writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET); + break; + + default: + return -EINVAL; + } + + return 0; +} + +static void rda_gpio_irq_unmask(struct irq_data *data) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + u32 offset = irqd_to_hwirq(data); + u32 trigger = irqd_get_trigger_type(data); + + gpiochip_enable_irq(chip, offset); + rda_gpio_set_irq(chip, offset, trigger); +} + +static int rda_gpio_irq_set_type(struct irq_data *data, unsigned int flow_type) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + u32 offset = irqd_to_hwirq(data); + int ret; + + ret = rda_gpio_set_irq(chip, offset, flow_type); + if (ret) + return ret; + + if (flow_type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)) + irq_set_handler_locked(data, handle_level_irq); + else if (flow_type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)) + irq_set_handler_locked(data, handle_edge_irq); + + return 0; +} + +static void rda_gpio_irq_handler(struct irq_desc *desc) +{ + struct gpio_chip *chip = irq_desc_get_handler_data(desc); + struct irq_chip *ic = irq_desc_get_chip(desc); + struct rda_gpio *rda_gpio = gpiochip_get_data(chip); + unsigned long status; + u32 n; + + chained_irq_enter(ic, desc); + + status = readl_relaxed(rda_gpio->base + RDA_GPIO_INT_STATUS); + /* Only lower 8 bits are capable of generating interrupts */ + status &= RDA_GPIO_IRQ_MASK; + + for_each_set_bit(n, &status, RDA_GPIO_BANK_NR) + generic_handle_domain_irq(chip->irq.domain, n); + + chained_irq_exit(ic, desc); +} + +static const struct irq_chip rda_gpio_irq_chip = { + .name = "rda-gpio", + .irq_ack = rda_gpio_irq_ack, + .irq_mask = rda_gpio_irq_mask, + .irq_unmask = rda_gpio_irq_unmask, + .irq_set_type = rda_gpio_irq_set_type, + .flags = IRQCHIP_SKIP_SET_WAKE | IRQCHIP_IMMUTABLE, + GPIOCHIP_IRQ_RESOURCE_HELPERS, +}; + +static int rda_gpio_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct gpio_irq_chip *girq; + struct rda_gpio *rda_gpio; + u32 ngpios; + int ret; + + rda_gpio = devm_kzalloc(dev, sizeof(*rda_gpio), GFP_KERNEL); + if (!rda_gpio) + return -ENOMEM; + + ret = device_property_read_u32(dev, "ngpios", &ngpios); + if (ret < 0) + return ret; + + /* + * Not all ports have interrupt capability. For instance, on + * RDA8810PL, GPIOC doesn't support interrupt. So we must handle + * those also. + */ + rda_gpio->irq = platform_get_irq(pdev, 0); + + rda_gpio->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(rda_gpio->base)) + return PTR_ERR(rda_gpio->base); + + spin_lock_init(&rda_gpio->lock); + + ret = bgpio_init(&rda_gpio->chip, dev, 4, + rda_gpio->base + RDA_GPIO_VAL, + rda_gpio->base + RDA_GPIO_SET, + rda_gpio->base + RDA_GPIO_CLR, + rda_gpio->base + RDA_GPIO_OEN_SET_OUT, + rda_gpio->base + RDA_GPIO_OEN_SET_IN, + BGPIOF_READ_OUTPUT_REG_SET); + if (ret) { + dev_err(dev, "bgpio_init failed\n"); + return ret; + } + + rda_gpio->chip.label = dev_name(dev); + rda_gpio->chip.ngpio = ngpios; + rda_gpio->chip.base = -1; + + if (rda_gpio->irq >= 0) { + girq = &rda_gpio->chip.irq; + gpio_irq_chip_set_chip(girq, &rda_gpio_irq_chip); + girq->handler = handle_bad_irq; + girq->default_type = IRQ_TYPE_NONE; + girq->parent_handler = rda_gpio_irq_handler; + girq->parent_handler_data = rda_gpio; + girq->num_parents = 1; + girq->parents = devm_kcalloc(dev, 1, + sizeof(*girq->parents), + GFP_KERNEL); + if (!girq->parents) + return -ENOMEM; + girq->parents[0] = rda_gpio->irq; + } + + platform_set_drvdata(pdev, rda_gpio); + + return devm_gpiochip_add_data(dev, &rda_gpio->chip, rda_gpio); +} + +static const struct of_device_id rda_gpio_of_match[] = { + { .compatible = "rda,8810pl-gpio", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, rda_gpio_of_match); + +static struct platform_driver rda_gpio_driver = { + .probe = rda_gpio_probe, + .driver = { + .name = "rda-gpio", + .of_match_table = rda_gpio_of_match, + }, +}; + +module_platform_driver_probe(rda_gpio_driver, rda_gpio_probe); + +MODULE_DESCRIPTION("RDA Micro GPIO driver"); +MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>"); |