linux/drivers/bcma/driver_gpio.c

255 lines
5.9 KiB
C

/*
* 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.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/irqdomain.h>
#include <linux/export.h>
#include <linux/bcma/bcma.h>
#include "bcma_private.h"
static inline struct bcma_drv_cc *bcma_gpio_get_cc(struct gpio_chip *chip)
{
return container_of(chip, struct bcma_drv_cc, gpio);
}
static int bcma_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
{
struct bcma_drv_cc *cc = bcma_gpio_get_cc(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 = bcma_gpio_get_cc(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 = bcma_gpio_get_cc(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 = bcma_gpio_get_cc(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 = bcma_gpio_get_cc(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 = bcma_gpio_get_cc(chip);
/* clear pullup */
bcma_chipco_gpio_pullup(cc, 1 << gpio, 0);
}
#if IS_BUILTIN(CONFIG_BCMA_HOST_SOC)
static int bcma_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
{
struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip);
if (cc->core->bus->hosttype == BCMA_HOSTTYPE_SOC)
return irq_find_mapping(cc->irq_domain, gpio);
else
return -EINVAL;
}
static void bcma_gpio_irq_unmask(struct irq_data *d)
{
struct bcma_drv_cc *cc = irq_data_get_irq_chip_data(d);
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 bcma_drv_cc *cc = irq_data_get_irq_chip_data(d);
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;
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, cc->gpio.ngpio)
generic_handle_irq(bcma_gpio_to_irq(&cc->gpio, gpio));
bcma_chipco_gpio_polarity(cc, irqs, val & irqs);
return IRQ_HANDLED;
}
static int bcma_gpio_irq_domain_init(struct bcma_drv_cc *cc)
{
struct gpio_chip *chip = &cc->gpio;
int gpio, hwirq, err;
if (cc->core->bus->hosttype != BCMA_HOSTTYPE_SOC)
return 0;
cc->irq_domain = irq_domain_add_linear(NULL, chip->ngpio,
&irq_domain_simple_ops, cc);
if (!cc->irq_domain) {
err = -ENODEV;
goto err_irq_domain;
}
for (gpio = 0; gpio < chip->ngpio; gpio++) {
int irq = irq_create_mapping(cc->irq_domain, gpio);
irq_set_chip_data(irq, cc);
irq_set_chip_and_handler(irq, &bcma_gpio_irq_chip,
handle_simple_irq);
}
hwirq = bcma_core_irq(cc->core);
err = request_irq(hwirq, bcma_gpio_irq_handler, IRQF_SHARED, "gpio",
cc);
if (err)
goto err_req_irq;
bcma_chipco_gpio_intmask(cc, ~0, 0);
bcma_cc_set32(cc, BCMA_CC_IRQMASK, BCMA_CC_IRQ_GPIO);
return 0;
err_req_irq:
for (gpio = 0; gpio < chip->ngpio; gpio++) {
int irq = irq_find_mapping(cc->irq_domain, gpio);
irq_dispose_mapping(irq);
}
irq_domain_remove(cc->irq_domain);
err_irq_domain:
return err;
}
static void bcma_gpio_irq_domain_exit(struct bcma_drv_cc *cc)
{
struct gpio_chip *chip = &cc->gpio;
int gpio;
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), cc);
for (gpio = 0; gpio < chip->ngpio; gpio++) {
int irq = irq_find_mapping(cc->irq_domain, gpio);
irq_dispose_mapping(irq);
}
irq_domain_remove(cc->irq_domain);
}
#else
static int bcma_gpio_irq_domain_init(struct bcma_drv_cc *cc)
{
return 0;
}
static void bcma_gpio_irq_domain_exit(struct bcma_drv_cc *cc)
{
}
#endif
int bcma_gpio_init(struct bcma_drv_cc *cc)
{
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;
#if IS_BUILTIN(CONFIG_BCMA_HOST_SOC)
chip->to_irq = bcma_gpio_to_irq;
#endif
switch (cc->core->bus->chipinfo.id) {
case BCMA_CHIP_ID_BCM5357:
chip->ngpio = 32;
break;
default:
chip->ngpio = 16;
}
/* There is just one SoC in one device and its GPIO addresses should be
* deterministic to address them more easily. The other buses could get
* a random base number. */
if (cc->core->bus->hosttype == BCMA_HOSTTYPE_SOC)
chip->base = 0;
else
chip->base = -1;
err = bcma_gpio_irq_domain_init(cc);
if (err)
return err;
err = gpiochip_add(chip);
if (err) {
bcma_gpio_irq_domain_exit(cc);
return err;
}
return 0;
}
int bcma_gpio_unregister(struct bcma_drv_cc *cc)
{
bcma_gpio_irq_domain_exit(cc);
return gpiochip_remove(&cc->gpio);
}