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/*
* Broadcom specific AMBA
* GPIO driver
*
* Copyright 2011, Broadcom Corporation
* Copyright 2012, Hauke Mehrtens <hauke@hauke-m.de>
*
* Licensed under the GNU/GPL. See COPYING for details.
*/
#include <linux/gpio/driver.h>
#include <linux/interrupt.h>
#include <linux/export.h>
#include <linux/bcma/bcma.h>
#include "bcma_private.h"
#define BCMA_GPIO_MAX_PINS 32
static int bcma_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
{
struct bcma_drv_cc *cc = gpiochip_get_data(chip);
return !!bcma_chipco_gpio_in(cc, 1 << gpio);
}
static void bcma_gpio_set_value(struct gpio_chip *chip, unsigned gpio,
int value)
{
struct bcma_drv_cc *cc = gpiochip_get_data(chip);
bcma_chipco_gpio_out(cc, 1 << gpio, value ? 1 << gpio : 0);
}
static int bcma_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
{
struct bcma_drv_cc *cc = gpiochip_get_data(chip);
bcma_chipco_gpio_outen(cc, 1 << gpio, 0);
return 0;
}
static int bcma_gpio_direction_output(struct gpio_chip *chip, unsigned gpio,
int value)
{
struct bcma_drv_cc *cc = gpiochip_get_data(chip);
bcma_chipco_gpio_outen(cc, 1 << gpio, 1 << gpio);
bcma_chipco_gpio_out(cc, 1 << gpio, value ? 1 << gpio : 0);
return 0;
}
static int bcma_gpio_request(struct gpio_chip *chip, unsigned gpio)
{
struct bcma_drv_cc *cc = gpiochip_get_data(chip);
bcma_chipco_gpio_control(cc, 1 << gpio, 0);
/* clear pulldown */
bcma_chipco_gpio_pulldown(cc, 1 << gpio, 0);
/* Set pullup */
bcma_chipco_gpio_pullup(cc, 1 << gpio, 1 << gpio);
return 0;
}
static void bcma_gpio_free(struct gpio_chip *chip, unsigned gpio)
{
struct bcma_drv_cc *cc = gpiochip_get_data(chip);
/* clear pullup */
bcma_chipco_gpio_pullup(cc, 1 << gpio, 0);
}
#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));
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);
}
static struct irq_chip bcma_gpio_irq_chip = {
.name = "BCMA-GPIO",
.irq_mask = bcma_gpio_irq_mask,
.irq_unmask = bcma_gpio_irq_unmask,
};
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_irq(irq_find_mapping(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;
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);
err = gpiochip_irqchip_add(chip,
&bcma_gpio_irq_chip,
0,
handle_simple_irq,
IRQ_TYPE_NONE);
if (err) {
free_irq(hwirq, cc);
return err;
}
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)
{
return 0;
}
static void bcma_gpio_irq_exit(struct bcma_drv_cc *cc)
{
}
#endif
int bcma_gpio_init(struct bcma_drv_cc *cc)
{
struct bcma_bus *bus = cc->core->bus;
struct gpio_chip *chip = &cc->gpio;
int err;
chip->label = "bcma_gpio";
chip->owner = THIS_MODULE;
chip->request = bcma_gpio_request;
chip->free = bcma_gpio_free;
chip->get = bcma_gpio_get_value;
chip->set = bcma_gpio_set_value;
chip->direction_input = bcma_gpio_direction_input;
chip->direction_output = bcma_gpio_direction_output;
chip->owner = THIS_MODULE;
chip->parent = bcma_bus_get_host_dev(bus);
#if IS_BUILTIN(CONFIG_OF)
chip->of_node = cc->core->dev.of_node;
#endif
switch (bus->chipinfo.id) {
case BCMA_CHIP_ID_BCM4707:
case BCMA_CHIP_ID_BCM5357:
case BCMA_CHIP_ID_BCM53572:
case BCMA_CHIP_ID_BCM53573:
case BCMA_CHIP_ID_BCM47094:
chip->ngpio = 32;
break;
default:
chip->ngpio = 16;
}
/*
* Register SoC GPIO devices with absolute GPIO pin base.
* On MIPS, we don't have Device Tree and we can't use relative (per chip)
* GPIO numbers.
* On some ARM devices, user space may want to access some system GPIO
* pins directly, which is easier to do with a predictable GPIO base.
*/
if (IS_BUILTIN(CONFIG_BCM47XX) ||
cc->core->bus->hosttype == BCMA_HOSTTYPE_SOC)
chip->base = bus->num * BCMA_GPIO_MAX_PINS;
else
chip->base = -1;
err = gpiochip_add_data(chip, cc);
if (err)
return err;
err = bcma_gpio_irq_init(cc);
if (err) {
gpiochip_remove(chip);
return err;
}
return 0;
}
int bcma_gpio_unregister(struct bcma_drv_cc *cc)
{
bcma_gpio_irq_exit(cc);
gpiochip_remove(&cc->gpio);
return 0;
}