diff options
Diffstat (limited to 'drivers/gpio/gpio-hlwd.c')
| -rw-r--r-- | drivers/gpio/gpio-hlwd.c | 192 |
1 files changed, 191 insertions, 1 deletions
diff --git a/drivers/gpio/gpio-hlwd.c b/drivers/gpio/gpio-hlwd.c index a63136a68ba3..a7b17897356e 100644 --- a/drivers/gpio/gpio-hlwd.c +++ b/drivers/gpio/gpio-hlwd.c @@ -48,9 +48,163 @@ struct hlwd_gpio { struct gpio_chip gpioc; + struct irq_chip irqc; void __iomem *regs; + int irq; + u32 edge_emulation; + u32 rising_edge, falling_edge; }; +static void hlwd_gpio_irqhandler(struct irq_desc *desc) +{ + struct hlwd_gpio *hlwd = + gpiochip_get_data(irq_desc_get_handler_data(desc)); + struct irq_chip *chip = irq_desc_get_chip(desc); + unsigned long flags; + unsigned long pending; + int hwirq; + u32 emulated_pending; + + spin_lock_irqsave(&hlwd->gpioc.bgpio_lock, flags); + pending = ioread32be(hlwd->regs + HW_GPIOB_INTFLAG); + pending &= ioread32be(hlwd->regs + HW_GPIOB_INTMASK); + + /* Treat interrupts due to edge trigger emulation separately */ + emulated_pending = hlwd->edge_emulation & pending; + pending &= ~emulated_pending; + if (emulated_pending) { + u32 level, rising, falling; + + level = ioread32be(hlwd->regs + HW_GPIOB_INTLVL); + rising = level & emulated_pending; + falling = ~level & emulated_pending; + + /* Invert the levels */ + iowrite32be(level ^ emulated_pending, + hlwd->regs + HW_GPIOB_INTLVL); + + /* Ack all emulated-edge interrupts */ + iowrite32be(emulated_pending, hlwd->regs + HW_GPIOB_INTFLAG); + + /* Signal interrupts only on the correct edge */ + rising &= hlwd->rising_edge; + falling &= hlwd->falling_edge; + + /* Mark emulated interrupts as pending */ + pending |= rising | falling; + } + spin_unlock_irqrestore(&hlwd->gpioc.bgpio_lock, flags); + + chained_irq_enter(chip, desc); + + for_each_set_bit(hwirq, &pending, 32) { + int irq = irq_find_mapping(hlwd->gpioc.irq.domain, hwirq); + + generic_handle_irq(irq); + } + + chained_irq_exit(chip, desc); +} + +static void hlwd_gpio_irq_ack(struct irq_data *data) +{ + struct hlwd_gpio *hlwd = + gpiochip_get_data(irq_data_get_irq_chip_data(data)); + + iowrite32be(BIT(data->hwirq), hlwd->regs + HW_GPIOB_INTFLAG); +} + +static void hlwd_gpio_irq_mask(struct irq_data *data) +{ + struct hlwd_gpio *hlwd = + gpiochip_get_data(irq_data_get_irq_chip_data(data)); + unsigned long flags; + u32 mask; + + spin_lock_irqsave(&hlwd->gpioc.bgpio_lock, flags); + mask = ioread32be(hlwd->regs + HW_GPIOB_INTMASK); + mask &= ~BIT(data->hwirq); + iowrite32be(mask, hlwd->regs + HW_GPIOB_INTMASK); + spin_unlock_irqrestore(&hlwd->gpioc.bgpio_lock, flags); +} + +static void hlwd_gpio_irq_unmask(struct irq_data *data) +{ + struct hlwd_gpio *hlwd = + gpiochip_get_data(irq_data_get_irq_chip_data(data)); + unsigned long flags; + u32 mask; + + spin_lock_irqsave(&hlwd->gpioc.bgpio_lock, flags); + mask = ioread32be(hlwd->regs + HW_GPIOB_INTMASK); + mask |= BIT(data->hwirq); + iowrite32be(mask, hlwd->regs + HW_GPIOB_INTMASK); + spin_unlock_irqrestore(&hlwd->gpioc.bgpio_lock, flags); +} + +static void hlwd_gpio_irq_enable(struct irq_data *data) +{ + hlwd_gpio_irq_ack(data); + hlwd_gpio_irq_unmask(data); +} + +static void hlwd_gpio_irq_setup_emulation(struct hlwd_gpio *hlwd, int hwirq, + unsigned int flow_type) +{ + u32 level, state; + + /* Set the trigger level to the inactive level */ + level = ioread32be(hlwd->regs + HW_GPIOB_INTLVL); + state = ioread32be(hlwd->regs + HW_GPIOB_IN) & BIT(hwirq); + level &= ~BIT(hwirq); + level |= state ^ BIT(hwirq); + iowrite32be(level, hlwd->regs + HW_GPIOB_INTLVL); + + hlwd->edge_emulation |= BIT(hwirq); + hlwd->rising_edge &= ~BIT(hwirq); + hlwd->falling_edge &= ~BIT(hwirq); + if (flow_type & IRQ_TYPE_EDGE_RISING) + hlwd->rising_edge |= BIT(hwirq); + if (flow_type & IRQ_TYPE_EDGE_FALLING) + hlwd->falling_edge |= BIT(hwirq); +} + +static int hlwd_gpio_irq_set_type(struct irq_data *data, unsigned int flow_type) +{ + struct hlwd_gpio *hlwd = + gpiochip_get_data(irq_data_get_irq_chip_data(data)); + unsigned long flags; + u32 level; + + spin_lock_irqsave(&hlwd->gpioc.bgpio_lock, flags); + + hlwd->edge_emulation &= ~BIT(data->hwirq); + + switch (flow_type) { + case IRQ_TYPE_LEVEL_HIGH: + level = ioread32be(hlwd->regs + HW_GPIOB_INTLVL); + level |= BIT(data->hwirq); + iowrite32be(level, hlwd->regs + HW_GPIOB_INTLVL); + break; + case IRQ_TYPE_LEVEL_LOW: + level = ioread32be(hlwd->regs + HW_GPIOB_INTLVL); + level &= ~BIT(data->hwirq); + iowrite32be(level, hlwd->regs + HW_GPIOB_INTLVL); + break; + case IRQ_TYPE_EDGE_RISING: + case IRQ_TYPE_EDGE_FALLING: + case IRQ_TYPE_EDGE_BOTH: + hlwd_gpio_irq_setup_emulation(hlwd, data->hwirq, flow_type); + break; + default: + spin_unlock_irqrestore(&hlwd->gpioc.bgpio_lock, flags); + return -EINVAL; + } + + spin_unlock_irqrestore(&hlwd->gpioc.bgpio_lock, flags); + return 0; +} + static int hlwd_gpio_probe(struct platform_device *pdev) { struct hlwd_gpio *hlwd; @@ -92,7 +246,43 @@ static int hlwd_gpio_probe(struct platform_device *pdev) ngpios = 32; hlwd->gpioc.ngpio = ngpios; - return devm_gpiochip_add_data(&pdev->dev, &hlwd->gpioc, hlwd); + res = devm_gpiochip_add_data(&pdev->dev, &hlwd->gpioc, hlwd); + if (res) + return res; + + /* Mask and ack all interrupts */ + iowrite32be(0, hlwd->regs + HW_GPIOB_INTMASK); + iowrite32be(0xffffffff, hlwd->regs + HW_GPIOB_INTFLAG); + + /* + * If this GPIO controller is not marked as an interrupt controller in + * the DT, return. + */ + if (!of_property_read_bool(pdev->dev.of_node, "interrupt-controller")) + return 0; + + hlwd->irq = platform_get_irq(pdev, 0); + if (hlwd->irq < 0) { + dev_info(&pdev->dev, "platform_get_irq returned %d\n", + hlwd->irq); + return hlwd->irq; + } + + hlwd->irqc.name = dev_name(&pdev->dev); + hlwd->irqc.irq_mask = hlwd_gpio_irq_mask; + hlwd->irqc.irq_unmask = hlwd_gpio_irq_unmask; + hlwd->irqc.irq_enable = hlwd_gpio_irq_enable; + hlwd->irqc.irq_set_type = hlwd_gpio_irq_set_type; + + res = gpiochip_irqchip_add(&hlwd->gpioc, &hlwd->irqc, 0, + handle_level_irq, IRQ_TYPE_NONE); + if (res) + return res; + + gpiochip_set_chained_irqchip(&hlwd->gpioc, &hlwd->irqc, + hlwd->irq, hlwd_gpio_irqhandler); + + return 0; } static const struct of_device_id hlwd_gpio_match[] = { |