| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Atheros AR71XX/AR724X/AR913X GPIO API support |
| * |
| * Copyright (C) 2015 Alban Bedel <albeu@free.fr> |
| * Copyright (C) 2010-2011 Jaiganesh Narayanan <jnarayanan@atheros.com> |
| * Copyright (C) 2008-2011 Gabor Juhos <juhosg@openwrt.org> |
| * Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org> |
| */ |
| |
| #include <linux/gpio/driver.h> |
| #include <linux/platform_data/gpio-ath79.h> |
| #include <linux/of_device.h> |
| #include <linux/interrupt.h> |
| #include <linux/module.h> |
| #include <linux/irq.h> |
| |
| #define AR71XX_GPIO_REG_OE 0x00 |
| #define AR71XX_GPIO_REG_IN 0x04 |
| #define AR71XX_GPIO_REG_SET 0x0c |
| #define AR71XX_GPIO_REG_CLEAR 0x10 |
| |
| #define AR71XX_GPIO_REG_INT_ENABLE 0x14 |
| #define AR71XX_GPIO_REG_INT_TYPE 0x18 |
| #define AR71XX_GPIO_REG_INT_POLARITY 0x1c |
| #define AR71XX_GPIO_REG_INT_PENDING 0x20 |
| #define AR71XX_GPIO_REG_INT_MASK 0x24 |
| |
| struct ath79_gpio_ctrl { |
| struct gpio_chip gc; |
| void __iomem *base; |
| raw_spinlock_t lock; |
| unsigned long both_edges; |
| }; |
| |
| static struct ath79_gpio_ctrl *irq_data_to_ath79_gpio(struct irq_data *data) |
| { |
| struct gpio_chip *gc = irq_data_get_irq_chip_data(data); |
| |
| return container_of(gc, struct ath79_gpio_ctrl, gc); |
| } |
| |
| static u32 ath79_gpio_read(struct ath79_gpio_ctrl *ctrl, unsigned reg) |
| { |
| return readl(ctrl->base + reg); |
| } |
| |
| static void ath79_gpio_write(struct ath79_gpio_ctrl *ctrl, |
| unsigned reg, u32 val) |
| { |
| writel(val, ctrl->base + reg); |
| } |
| |
| static bool ath79_gpio_update_bits( |
| struct ath79_gpio_ctrl *ctrl, unsigned reg, u32 mask, u32 bits) |
| { |
| u32 old_val, new_val; |
| |
| old_val = ath79_gpio_read(ctrl, reg); |
| new_val = (old_val & ~mask) | (bits & mask); |
| |
| if (new_val != old_val) |
| ath79_gpio_write(ctrl, reg, new_val); |
| |
| return new_val != old_val; |
| } |
| |
| static void ath79_gpio_irq_unmask(struct irq_data *data) |
| { |
| struct ath79_gpio_ctrl *ctrl = irq_data_to_ath79_gpio(data); |
| u32 mask = BIT(irqd_to_hwirq(data)); |
| unsigned long flags; |
| |
| raw_spin_lock_irqsave(&ctrl->lock, flags); |
| ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_MASK, mask, mask); |
| raw_spin_unlock_irqrestore(&ctrl->lock, flags); |
| } |
| |
| static void ath79_gpio_irq_mask(struct irq_data *data) |
| { |
| struct ath79_gpio_ctrl *ctrl = irq_data_to_ath79_gpio(data); |
| u32 mask = BIT(irqd_to_hwirq(data)); |
| unsigned long flags; |
| |
| raw_spin_lock_irqsave(&ctrl->lock, flags); |
| ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_MASK, mask, 0); |
| raw_spin_unlock_irqrestore(&ctrl->lock, flags); |
| } |
| |
| static void ath79_gpio_irq_enable(struct irq_data *data) |
| { |
| struct ath79_gpio_ctrl *ctrl = irq_data_to_ath79_gpio(data); |
| u32 mask = BIT(irqd_to_hwirq(data)); |
| unsigned long flags; |
| |
| raw_spin_lock_irqsave(&ctrl->lock, flags); |
| ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_ENABLE, mask, mask); |
| ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_MASK, mask, mask); |
| raw_spin_unlock_irqrestore(&ctrl->lock, flags); |
| } |
| |
| static void ath79_gpio_irq_disable(struct irq_data *data) |
| { |
| struct ath79_gpio_ctrl *ctrl = irq_data_to_ath79_gpio(data); |
| u32 mask = BIT(irqd_to_hwirq(data)); |
| unsigned long flags; |
| |
| raw_spin_lock_irqsave(&ctrl->lock, flags); |
| ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_MASK, mask, 0); |
| ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_ENABLE, mask, 0); |
| raw_spin_unlock_irqrestore(&ctrl->lock, flags); |
| } |
| |
| static int ath79_gpio_irq_set_type(struct irq_data *data, |
| unsigned int flow_type) |
| { |
| struct ath79_gpio_ctrl *ctrl = irq_data_to_ath79_gpio(data); |
| u32 mask = BIT(irqd_to_hwirq(data)); |
| u32 type = 0, polarity = 0; |
| unsigned long flags; |
| bool disabled; |
| |
| switch (flow_type) { |
| case IRQ_TYPE_EDGE_RISING: |
| polarity |= mask; |
| fallthrough; |
| case IRQ_TYPE_EDGE_FALLING: |
| case IRQ_TYPE_EDGE_BOTH: |
| break; |
| |
| case IRQ_TYPE_LEVEL_HIGH: |
| polarity |= mask; |
| fallthrough; |
| case IRQ_TYPE_LEVEL_LOW: |
| type |= mask; |
| break; |
| |
| default: |
| return -EINVAL; |
| } |
| |
| raw_spin_lock_irqsave(&ctrl->lock, flags); |
| |
| if (flow_type == IRQ_TYPE_EDGE_BOTH) { |
| ctrl->both_edges |= mask; |
| polarity = ~ath79_gpio_read(ctrl, AR71XX_GPIO_REG_IN); |
| } else { |
| ctrl->both_edges &= ~mask; |
| } |
| |
| /* As the IRQ configuration can't be loaded atomically we |
| * have to disable the interrupt while the configuration state |
| * is invalid. |
| */ |
| disabled = ath79_gpio_update_bits( |
| ctrl, AR71XX_GPIO_REG_INT_ENABLE, mask, 0); |
| |
| ath79_gpio_update_bits( |
| ctrl, AR71XX_GPIO_REG_INT_TYPE, mask, type); |
| ath79_gpio_update_bits( |
| ctrl, AR71XX_GPIO_REG_INT_POLARITY, mask, polarity); |
| |
| if (disabled) |
| ath79_gpio_update_bits( |
| ctrl, AR71XX_GPIO_REG_INT_ENABLE, mask, mask); |
| |
| raw_spin_unlock_irqrestore(&ctrl->lock, flags); |
| |
| return 0; |
| } |
| |
| static struct irq_chip ath79_gpio_irqchip = { |
| .name = "gpio-ath79", |
| .irq_enable = ath79_gpio_irq_enable, |
| .irq_disable = ath79_gpio_irq_disable, |
| .irq_mask = ath79_gpio_irq_mask, |
| .irq_unmask = ath79_gpio_irq_unmask, |
| .irq_set_type = ath79_gpio_irq_set_type, |
| }; |
| |
| static void ath79_gpio_irq_handler(struct irq_desc *desc) |
| { |
| struct gpio_chip *gc = irq_desc_get_handler_data(desc); |
| struct irq_chip *irqchip = irq_desc_get_chip(desc); |
| struct ath79_gpio_ctrl *ctrl = |
| container_of(gc, struct ath79_gpio_ctrl, gc); |
| unsigned long flags, pending; |
| u32 both_edges, state; |
| int irq; |
| |
| chained_irq_enter(irqchip, desc); |
| |
| raw_spin_lock_irqsave(&ctrl->lock, flags); |
| |
| pending = ath79_gpio_read(ctrl, AR71XX_GPIO_REG_INT_PENDING); |
| |
| /* Update the polarity of the both edges irqs */ |
| both_edges = ctrl->both_edges & pending; |
| if (both_edges) { |
| state = ath79_gpio_read(ctrl, AR71XX_GPIO_REG_IN); |
| ath79_gpio_update_bits(ctrl, AR71XX_GPIO_REG_INT_POLARITY, |
| both_edges, ~state); |
| } |
| |
| raw_spin_unlock_irqrestore(&ctrl->lock, flags); |
| |
| if (pending) { |
| for_each_set_bit(irq, &pending, gc->ngpio) |
| generic_handle_irq( |
| irq_linear_revmap(gc->irq.domain, irq)); |
| } |
| |
| chained_irq_exit(irqchip, desc); |
| } |
| |
| static const struct of_device_id ath79_gpio_of_match[] = { |
| { .compatible = "qca,ar7100-gpio" }, |
| { .compatible = "qca,ar9340-gpio" }, |
| {}, |
| }; |
| MODULE_DEVICE_TABLE(of, ath79_gpio_of_match); |
| |
| static int ath79_gpio_probe(struct platform_device *pdev) |
| { |
| struct ath79_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev); |
| struct device *dev = &pdev->dev; |
| struct device_node *np = dev->of_node; |
| struct ath79_gpio_ctrl *ctrl; |
| struct gpio_irq_chip *girq; |
| u32 ath79_gpio_count; |
| bool oe_inverted; |
| int err; |
| |
| ctrl = devm_kzalloc(dev, sizeof(*ctrl), GFP_KERNEL); |
| if (!ctrl) |
| return -ENOMEM; |
| platform_set_drvdata(pdev, ctrl); |
| |
| if (np) { |
| err = of_property_read_u32(np, "ngpios", &ath79_gpio_count); |
| if (err) { |
| dev_err(dev, "ngpios property is not valid\n"); |
| return err; |
| } |
| oe_inverted = of_device_is_compatible(np, "qca,ar9340-gpio"); |
| } else if (pdata) { |
| ath79_gpio_count = pdata->ngpios; |
| oe_inverted = pdata->oe_inverted; |
| } else { |
| dev_err(dev, "No DT node or platform data found\n"); |
| return -EINVAL; |
| } |
| |
| if (ath79_gpio_count >= 32) { |
| dev_err(dev, "ngpios must be less than 32\n"); |
| return -EINVAL; |
| } |
| |
| ctrl->base = devm_platform_ioremap_resource(pdev, 0); |
| if (IS_ERR(ctrl->base)) |
| return PTR_ERR(ctrl->base); |
| |
| raw_spin_lock_init(&ctrl->lock); |
| err = bgpio_init(&ctrl->gc, dev, 4, |
| ctrl->base + AR71XX_GPIO_REG_IN, |
| ctrl->base + AR71XX_GPIO_REG_SET, |
| ctrl->base + AR71XX_GPIO_REG_CLEAR, |
| oe_inverted ? NULL : ctrl->base + AR71XX_GPIO_REG_OE, |
| oe_inverted ? ctrl->base + AR71XX_GPIO_REG_OE : NULL, |
| 0); |
| if (err) { |
| dev_err(dev, "bgpio_init failed\n"); |
| return err; |
| } |
| /* Use base 0 to stay compatible with legacy platforms */ |
| ctrl->gc.base = 0; |
| |
| /* Optional interrupt setup */ |
| if (!np || of_property_read_bool(np, "interrupt-controller")) { |
| girq = &ctrl->gc.irq; |
| girq->chip = &ath79_gpio_irqchip; |
| girq->parent_handler = ath79_gpio_irq_handler; |
| girq->num_parents = 1; |
| girq->parents = devm_kcalloc(dev, 1, sizeof(*girq->parents), |
| GFP_KERNEL); |
| if (!girq->parents) |
| return -ENOMEM; |
| girq->parents[0] = platform_get_irq(pdev, 0); |
| girq->default_type = IRQ_TYPE_NONE; |
| girq->handler = handle_simple_irq; |
| } |
| |
| err = devm_gpiochip_add_data(dev, &ctrl->gc, ctrl); |
| if (err) { |
| dev_err(dev, |
| "cannot add AR71xx GPIO chip, error=%d", err); |
| return err; |
| } |
| return 0; |
| } |
| |
| static struct platform_driver ath79_gpio_driver = { |
| .driver = { |
| .name = "ath79-gpio", |
| .of_match_table = ath79_gpio_of_match, |
| }, |
| .probe = ath79_gpio_probe, |
| }; |
| |
| module_platform_driver(ath79_gpio_driver); |
| |
| MODULE_DESCRIPTION("Atheros AR71XX/AR724X/AR913X GPIO API support"); |
| MODULE_LICENSE("GPL v2"); |