linux/drivers/bcma/driver_gpio.c

/*
 * Broadcom specific AMBA
 * GPIO driver
 *
 * Copyright 2011, Broadcom Corporation
 * Copyright 2012, Hauke Mehrtens <[email protected]>
 *
 * Licensed under the GNU/GPL. See COPYING for details.
 */

#include <linux/gpio/driver.h>
#include <linux/interrupt.h>
#include <linux/export.h>
#include <linux/property.h>

#include <linux/bcma/bcma.h>

#include "bcma_private.h"

#define BCMA_GPIO_MAX_PINS …

static int bcma_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
{ … }

static void bcma_gpio_set_value(struct gpio_chip *chip, unsigned gpio,
				int value)
{ … }

static int bcma_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
{ … }

static int bcma_gpio_direction_output(struct gpio_chip *chip, unsigned gpio,
				      int value)
{ … }

static int bcma_gpio_request(struct gpio_chip *chip, unsigned gpio)
{ … }

static void bcma_gpio_free(struct gpio_chip *chip, unsigned gpio)
{ … }

#if IS_BUILTIN(CONFIG_BCM47XX) || IS_BUILTIN(CONFIG_ARCH_BCM_5301X)

static void bcma_gpio_irq_unmask(struct irq_data *d)
{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct bcma_drv_cc *cc = gpiochip_get_data(gc);
	int gpio = irqd_to_hwirq(d);
	u32 val = bcma_chipco_gpio_in(cc, BIT(gpio));

	gpiochip_enable_irq(gc, gpio);
	bcma_chipco_gpio_polarity(cc, BIT(gpio), val);
	bcma_chipco_gpio_intmask(cc, BIT(gpio), BIT(gpio));
}

static void bcma_gpio_irq_mask(struct irq_data *d)
{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct bcma_drv_cc *cc = gpiochip_get_data(gc);
	int gpio = irqd_to_hwirq(d);

	bcma_chipco_gpio_intmask(cc, BIT(gpio), 0);
	gpiochip_disable_irq(gc, gpio);
}

static const struct irq_chip bcma_gpio_irq_chip = {
	.name		= "BCMA-GPIO",
	.irq_mask	= bcma_gpio_irq_mask,
	.irq_unmask	= bcma_gpio_irq_unmask,
	.flags		= IRQCHIP_IMMUTABLE,
	GPIOCHIP_IRQ_RESOURCE_HELPERS,
};

static irqreturn_t bcma_gpio_irq_handler(int irq, void *dev_id)
{
	struct bcma_drv_cc *cc = dev_id;
	struct gpio_chip *gc = &cc->gpio;
	u32 val = bcma_cc_read32(cc, BCMA_CC_GPIOIN);
	u32 mask = bcma_cc_read32(cc, BCMA_CC_GPIOIRQ);
	u32 pol = bcma_cc_read32(cc, BCMA_CC_GPIOPOL);
	unsigned long irqs = (val ^ pol) & mask;
	int gpio;

	if (!irqs)
		return IRQ_NONE;

	for_each_set_bit(gpio, &irqs, gc->ngpio)
		generic_handle_domain_irq_safe(gc->irq.domain, gpio);
	bcma_chipco_gpio_polarity(cc, irqs, val & irqs);

	return IRQ_HANDLED;
}

static int bcma_gpio_irq_init(struct bcma_drv_cc *cc)
{
	struct gpio_chip *chip = &cc->gpio;
	struct gpio_irq_chip *girq = &chip->irq;
	int hwirq, err;

	if (cc->core->bus->hosttype != BCMA_HOSTTYPE_SOC)
		return 0;

	hwirq = bcma_core_irq(cc->core, 0);
	err = request_irq(hwirq, bcma_gpio_irq_handler, IRQF_SHARED, "gpio",
			  cc);
	if (err)
		return err;

	bcma_chipco_gpio_intmask(cc, ~0, 0);
	bcma_cc_set32(cc, BCMA_CC_IRQMASK, BCMA_CC_IRQ_GPIO);

	gpio_irq_chip_set_chip(girq, &bcma_gpio_irq_chip);
	/* This will let us handle the parent IRQ in the driver */
	girq->parent_handler = NULL;
	girq->num_parents = 0;
	girq->parents = NULL;
	girq->default_type = IRQ_TYPE_NONE;
	girq->handler = handle_simple_irq;

	return 0;
}

static void bcma_gpio_irq_exit(struct bcma_drv_cc *cc)
{
	if (cc->core->bus->hosttype != BCMA_HOSTTYPE_SOC)
		return;

	bcma_cc_mask32(cc, BCMA_CC_IRQMASK, ~BCMA_CC_IRQ_GPIO);
	free_irq(bcma_core_irq(cc->core, 0), cc);
}
#else
static int bcma_gpio_irq_init(struct bcma_drv_cc *cc)
{ … }

static void bcma_gpio_irq_exit(struct bcma_drv_cc *cc)
{ … }
#endif

int bcma_gpio_init(struct bcma_drv_cc *cc)
{ … }

int bcma_gpio_unregister(struct bcma_drv_cc *cc)
{ … }