/* * 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> * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published * by the Free Software Foundation. */ #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) { return 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; case IRQ_TYPE_EDGE_FALLING: case IRQ_TYPE_EDGE_BOTH: break; case IRQ_TYPE_LEVEL_HIGH: polarity |= mask; /* fall through */ 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_node *np = pdev->dev.of_node; struct ath79_gpio_ctrl *ctrl; struct resource *res; u32 ath79_gpio_count; bool oe_inverted; int err; ctrl = devm_kzalloc(&pdev->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(&pdev->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(&pdev->dev, "No DT node or platform data found\n"); return -EINVAL; } if (ath79_gpio_count >= 32) { dev_err(&pdev->dev, "ngpios must be less than 32\n"); return -EINVAL; } res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) return -EINVAL; ctrl->base = devm_ioremap_nocache( &pdev->dev, res->start, resource_size(res)); if (!ctrl->base) return -ENOMEM; raw_spin_lock_init(&ctrl->lock); err = bgpio_init(&ctrl->gc, &pdev->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(&pdev->dev, "bgpio_init failed\n"); return err; } /* Use base 0 to stay compatible with legacy platforms */ ctrl->gc.base = 0; err = gpiochip_add_data(&ctrl->gc, ctrl); if (err) { dev_err(&pdev->dev, "cannot add AR71xx GPIO chip, error=%d", err); return err; } if (np && !of_property_read_bool(np, "interrupt-controller")) return 0; err = gpiochip_irqchip_add(&ctrl->gc, &ath79_gpio_irqchip, 0, handle_simple_irq, IRQ_TYPE_NONE); if (err) { dev_err(&pdev->dev, "failed to add gpiochip_irqchip\n"); goto gpiochip_remove; } gpiochip_set_chained_irqchip(&ctrl->gc, &ath79_gpio_irqchip, platform_get_irq(pdev, 0), ath79_gpio_irq_handler); return 0; gpiochip_remove: gpiochip_remove(&ctrl->gc); return err; } static int ath79_gpio_remove(struct platform_device *pdev) { struct ath79_gpio_ctrl *ctrl = platform_get_drvdata(pdev); gpiochip_remove(&ctrl->gc); return 0; } static struct platform_driver ath79_gpio_driver = { .driver = { .name = "ath79-gpio", .of_match_table = ath79_gpio_of_match, }, .probe = ath79_gpio_probe, .remove = ath79_gpio_remove, }; module_platform_driver(ath79_gpio_driver); MODULE_DESCRIPTION("Atheros AR71XX/AR724X/AR913X GPIO API support"); MODULE_LICENSE("GPL v2");