From a11841477af65f07eccd726c1421d16d3f276088 Mon Sep 17 00:00:00 2001 From: William Breathitt Gray Date: Tue, 3 Nov 2015 07:54:23 -0500 Subject: [PATCH] gpio: Add IRQ support to ACCES 104-IDIO-16 driver The ACCES 104-IDIO-16 series offers Change-of-State detection interrupt functionality; if Change-of-State detection is enabled, an interrupt is fired off if any input line changes state (i.e. goes from low to high, or from high to low). This patch adds support to handle these interrupts and allows the user to mask which GPIO lines are affected. The interrupt line number for the device may be set via the idio_16_irq module parameter. Signed-off-by: William Breathitt Gray Signed-off-by: Linus Walleij --- drivers/gpio/Kconfig | 6 +- drivers/gpio/gpio-104-idio-16.c | 112 +++++++++++++++++++++++++++++++- 2 files changed, 116 insertions(+), 2 deletions(-) diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index b18bea08ff25..18e1aa05a616 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -496,8 +496,12 @@ menu "Port-mapped I/O GPIO drivers" config GPIO_104_IDIO_16 tristate "ACCES 104-IDIO-16 GPIO support" + select GPIOLIB_IRQCHIP help - Enables GPIO support for the ACCES 104-IDIO-16 family. + Enables GPIO support for the ACCES 104-IDIO-16 family. The base port + address for the device may be set via the idio_16_base module + parameter. The interrupt line number for the device may be set via the + idio_16_irq module parameter. config GPIO_F7188X tristate "F71869, F71869A, F71882FG and F71889F GPIO support" diff --git a/drivers/gpio/gpio-104-idio-16.c b/drivers/gpio/gpio-104-idio-16.c index 107cfd7105a8..4e8adee4d8c2 100644 --- a/drivers/gpio/gpio-104-idio-16.c +++ b/drivers/gpio/gpio-104-idio-16.c @@ -11,11 +11,14 @@ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. */ +#include #include #include #include #include #include +#include +#include #include #include #include @@ -25,20 +28,27 @@ static unsigned idio_16_base; module_param(idio_16_base, uint, 0); MODULE_PARM_DESC(idio_16_base, "ACCES 104-IDIO-16 base address"); +static unsigned idio_16_irq; +module_param(idio_16_irq, uint, 0); +MODULE_PARM_DESC(idio_16_irq, "ACCES 104-IDIO-16 interrupt line number"); /** * struct idio_16_gpio - GPIO device private data structure * @chip: instance of the gpio_chip - * @lock: synchronization lock to prevent gpio_set race conditions + * @lock: synchronization lock to prevent I/O race conditions + * @irq_mask: I/O bits affected by interrupts * @base: base port address of the GPIO device * @extent: extent of port address region of the GPIO device + * @irq: Interrupt line number * @out_state: output bits state */ struct idio_16_gpio { struct gpio_chip chip; spinlock_t lock; + unsigned long irq_mask; unsigned base; unsigned extent; + unsigned irq; unsigned out_state; }; @@ -105,6 +115,87 @@ static void idio_16_gpio_set(struct gpio_chip *chip, unsigned offset, int value) spin_unlock_irqrestore(&idio16gpio->lock, flags); } +static void idio_16_irq_ack(struct irq_data *data) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + struct idio_16_gpio *const idio16gpio = to_idio16gpio(chip); + unsigned long flags; + + spin_lock_irqsave(&idio16gpio->lock, flags); + + outb(0, idio16gpio->base + 1); + + spin_unlock_irqrestore(&idio16gpio->lock, flags); +} + +static void idio_16_irq_mask(struct irq_data *data) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + struct idio_16_gpio *const idio16gpio = to_idio16gpio(chip); + const unsigned long mask = BIT(irqd_to_hwirq(data)); + unsigned long flags; + + idio16gpio->irq_mask &= ~mask; + + if (!idio16gpio->irq_mask) { + spin_lock_irqsave(&idio16gpio->lock, flags); + + outb(0, idio16gpio->base + 2); + + spin_unlock_irqrestore(&idio16gpio->lock, flags); + } +} + +static void idio_16_irq_unmask(struct irq_data *data) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(data); + struct idio_16_gpio *const idio16gpio = to_idio16gpio(chip); + const unsigned long mask = BIT(irqd_to_hwirq(data)); + const unsigned long prev_irq_mask = idio16gpio->irq_mask; + unsigned long flags; + + idio16gpio->irq_mask |= mask; + + if (!prev_irq_mask) { + spin_lock_irqsave(&idio16gpio->lock, flags); + + outb(0, idio16gpio->base + 1); + inb(idio16gpio->base + 2); + + spin_unlock_irqrestore(&idio16gpio->lock, flags); + } +} + +static int idio_16_irq_set_type(struct irq_data *data, unsigned flow_type) +{ + /* The only valid irq types are none and both-edges */ + if (flow_type != IRQ_TYPE_NONE && + (flow_type & IRQ_TYPE_EDGE_BOTH) != IRQ_TYPE_EDGE_BOTH) + return -EINVAL; + + return 0; +} + +static struct irq_chip idio_16_irqchip = { + .name = "104-idio-16", + .irq_ack = idio_16_irq_ack, + .irq_mask = idio_16_irq_mask, + .irq_unmask = idio_16_irq_unmask, + .irq_set_type = idio_16_irq_set_type +}; + +static irqreturn_t idio_16_irq_handler(int irq, void *dev_id) +{ + struct idio_16_gpio *const idio16gpio = dev_id; + struct gpio_chip *const chip = &idio16gpio->chip; + int gpio; + + for_each_set_bit(gpio, &idio16gpio->irq_mask, chip->ngpio) + generic_handle_irq(irq_find_mapping(chip->irqdomain, gpio)); + + return IRQ_HANDLED; +} + static int __init idio_16_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -113,6 +204,7 @@ static int __init idio_16_probe(struct platform_device *pdev) const unsigned BASE = idio_16_base; const unsigned EXTENT = 8; + const unsigned IRQ = idio_16_irq; const char *const NAME = dev_name(dev); idio16gpio = devm_kzalloc(dev, sizeof(*idio16gpio), GFP_KERNEL); @@ -138,6 +230,7 @@ static int __init idio_16_probe(struct platform_device *pdev) idio16gpio->chip.set = idio_16_gpio_set; idio16gpio->base = BASE; idio16gpio->extent = EXTENT; + idio16gpio->irq = IRQ; idio16gpio->out_state = 0xFFFF; spin_lock_init(&idio16gpio->lock); @@ -150,8 +243,24 @@ static int __init idio_16_probe(struct platform_device *pdev) goto err_gpio_register; } + err = gpiochip_irqchip_add(&idio16gpio->chip, &idio_16_irqchip, 0, + handle_edge_irq, IRQ_TYPE_NONE); + if (err) { + dev_err(dev, "Could not add irqchip (%d)\n", err); + goto err_gpiochip_irqchip_add; + } + + err = request_irq(IRQ, idio_16_irq_handler, 0, NAME, idio16gpio); + if (err) { + dev_err(dev, "IRQ handler registering failed (%d)\n", err); + goto err_request_irq; + } + return 0; +err_request_irq: +err_gpiochip_irqchip_add: + gpiochip_remove(&idio16gpio->chip); err_gpio_register: release_region(BASE, EXTENT); err_lock_io_port: @@ -162,6 +271,7 @@ static int idio_16_remove(struct platform_device *pdev) { struct idio_16_gpio *const idio16gpio = platform_get_drvdata(pdev); + free_irq(idio16gpio->irq, idio16gpio); gpiochip_remove(&idio16gpio->chip); release_region(idio16gpio->base, idio16gpio->extent); -- 2.30.2