linux/drivers/ssb/driver_gpio.c
Hauke Mehrtens ec43b08b57 ssb: add GPIO driver
Register a GPIO driver to access the GPIOs provided by the chip.
The GPIOs of the SoC should always start at 0 and the other GPIOs could
start at a random position. There is just one SoC in a system and when
they start at 0 the number is predictable.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Patchwork: http://patchwork.linux-mips.org/patch/4591
Acked-by: Florian Fainelli <florian@openwrt.org>
2012-11-21 21:55:52 +01:00

176 lines
4.4 KiB
C

/*
* Sonics Silicon Backplane
* 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/export.h>
#include <linux/ssb/ssb.h>
#include "ssb_private.h"
static struct ssb_bus *ssb_gpio_get_bus(struct gpio_chip *chip)
{
return container_of(chip, struct ssb_bus, gpio);
}
static int ssb_gpio_chipco_get_value(struct gpio_chip *chip, unsigned gpio)
{
struct ssb_bus *bus = ssb_gpio_get_bus(chip);
return !!ssb_chipco_gpio_in(&bus->chipco, 1 << gpio);
}
static void ssb_gpio_chipco_set_value(struct gpio_chip *chip, unsigned gpio,
int value)
{
struct ssb_bus *bus = ssb_gpio_get_bus(chip);
ssb_chipco_gpio_out(&bus->chipco, 1 << gpio, value ? 1 << gpio : 0);
}
static int ssb_gpio_chipco_direction_input(struct gpio_chip *chip,
unsigned gpio)
{
struct ssb_bus *bus = ssb_gpio_get_bus(chip);
ssb_chipco_gpio_outen(&bus->chipco, 1 << gpio, 0);
return 0;
}
static int ssb_gpio_chipco_direction_output(struct gpio_chip *chip,
unsigned gpio, int value)
{
struct ssb_bus *bus = ssb_gpio_get_bus(chip);
ssb_chipco_gpio_outen(&bus->chipco, 1 << gpio, 1 << gpio);
ssb_chipco_gpio_out(&bus->chipco, 1 << gpio, value ? 1 << gpio : 0);
return 0;
}
static int ssb_gpio_chipco_request(struct gpio_chip *chip, unsigned gpio)
{
struct ssb_bus *bus = ssb_gpio_get_bus(chip);
ssb_chipco_gpio_control(&bus->chipco, 1 << gpio, 0);
/* clear pulldown */
ssb_chipco_gpio_pulldown(&bus->chipco, 1 << gpio, 0);
/* Set pullup */
ssb_chipco_gpio_pullup(&bus->chipco, 1 << gpio, 1 << gpio);
return 0;
}
static void ssb_gpio_chipco_free(struct gpio_chip *chip, unsigned gpio)
{
struct ssb_bus *bus = ssb_gpio_get_bus(chip);
/* clear pullup */
ssb_chipco_gpio_pullup(&bus->chipco, 1 << gpio, 0);
}
static int ssb_gpio_chipco_init(struct ssb_bus *bus)
{
struct gpio_chip *chip = &bus->gpio;
chip->label = "ssb_chipco_gpio";
chip->owner = THIS_MODULE;
chip->request = ssb_gpio_chipco_request;
chip->free = ssb_gpio_chipco_free;
chip->get = ssb_gpio_chipco_get_value;
chip->set = ssb_gpio_chipco_set_value;
chip->direction_input = ssb_gpio_chipco_direction_input;
chip->direction_output = ssb_gpio_chipco_direction_output;
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 (bus->bustype == SSB_BUSTYPE_SSB)
chip->base = 0;
else
chip->base = -1;
return gpiochip_add(chip);
}
#ifdef CONFIG_SSB_DRIVER_EXTIF
static int ssb_gpio_extif_get_value(struct gpio_chip *chip, unsigned gpio)
{
struct ssb_bus *bus = ssb_gpio_get_bus(chip);
return !!ssb_extif_gpio_in(&bus->extif, 1 << gpio);
}
static void ssb_gpio_extif_set_value(struct gpio_chip *chip, unsigned gpio,
int value)
{
struct ssb_bus *bus = ssb_gpio_get_bus(chip);
ssb_extif_gpio_out(&bus->extif, 1 << gpio, value ? 1 << gpio : 0);
}
static int ssb_gpio_extif_direction_input(struct gpio_chip *chip,
unsigned gpio)
{
struct ssb_bus *bus = ssb_gpio_get_bus(chip);
ssb_extif_gpio_outen(&bus->extif, 1 << gpio, 0);
return 0;
}
static int ssb_gpio_extif_direction_output(struct gpio_chip *chip,
unsigned gpio, int value)
{
struct ssb_bus *bus = ssb_gpio_get_bus(chip);
ssb_extif_gpio_outen(&bus->extif, 1 << gpio, 1 << gpio);
ssb_extif_gpio_out(&bus->extif, 1 << gpio, value ? 1 << gpio : 0);
return 0;
}
static int ssb_gpio_extif_init(struct ssb_bus *bus)
{
struct gpio_chip *chip = &bus->gpio;
chip->label = "ssb_extif_gpio";
chip->owner = THIS_MODULE;
chip->get = ssb_gpio_extif_get_value;
chip->set = ssb_gpio_extif_set_value;
chip->direction_input = ssb_gpio_extif_direction_input;
chip->direction_output = ssb_gpio_extif_direction_output;
chip->ngpio = 5;
/* 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 (bus->bustype == SSB_BUSTYPE_SSB)
chip->base = 0;
else
chip->base = -1;
return gpiochip_add(chip);
}
#else
static int ssb_gpio_extif_init(struct ssb_bus *bus)
{
return -ENOTSUPP;
}
#endif
int ssb_gpio_init(struct ssb_bus *bus)
{
if (ssb_chipco_available(&bus->chipco))
return ssb_gpio_chipco_init(bus);
else if (ssb_extif_available(&bus->extif))
return ssb_gpio_extif_init(bus);
else
SSB_WARN_ON(1);
return -1;
}