u-boot/drivers/gpio/bcm2835_gpio.c
Alexander Graf caf2233b28 bcm283x: Add pinctrl driver
The bcm283x family of SoCs have a GPIO controller that also acts as
pinctrl controller.

This patch introduces a new pinctrl driver that can actually properly mux
devices into their device tree defined pin states and is now the primary
owner of the gpio device. The previous GPIO driver gets moved into a
subdevice of the pinctrl driver, bound to the same OF node.

That way whenever a device asks for pinctrl support, it gets it
automatically from the pinctrl driver and GPIO support is still available
in the normal command line phase.

Signed-off-by: Alexander Graf <agraf@suse.de>
2018-01-28 12:27:32 -05:00

143 lines
3.6 KiB
C

/*
* Copyright (C) 2012 Vikram Narayananan
* <vikram186@gmail.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <dm.h>
#include <dm/pinctrl.h>
#include <errno.h>
#include <asm/gpio.h>
#include <asm/io.h>
#include <fdtdec.h>
struct bcm2835_gpios {
struct bcm2835_gpio_regs *reg;
struct udevice *pinctrl;
};
static int bcm2835_gpio_direction_input(struct udevice *dev, unsigned gpio)
{
struct bcm2835_gpios *gpios = dev_get_priv(dev);
unsigned val;
val = readl(&gpios->reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]);
val &= ~(BCM2835_GPIO_FSEL_MASK << BCM2835_GPIO_FSEL_SHIFT(gpio));
val |= (BCM2835_GPIO_INPUT << BCM2835_GPIO_FSEL_SHIFT(gpio));
writel(val, &gpios->reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]);
return 0;
}
static int bcm2835_gpio_direction_output(struct udevice *dev, unsigned int gpio,
int value)
{
struct bcm2835_gpios *gpios = dev_get_priv(dev);
unsigned val;
gpio_set_value(gpio, value);
val = readl(&gpios->reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]);
val &= ~(BCM2835_GPIO_FSEL_MASK << BCM2835_GPIO_FSEL_SHIFT(gpio));
val |= (BCM2835_GPIO_OUTPUT << BCM2835_GPIO_FSEL_SHIFT(gpio));
writel(val, &gpios->reg->gpfsel[BCM2835_GPIO_FSEL_BANK(gpio)]);
return 0;
}
static int bcm2835_get_value(const struct bcm2835_gpios *gpios, unsigned gpio)
{
unsigned val;
val = readl(&gpios->reg->gplev[BCM2835_GPIO_COMMON_BANK(gpio)]);
return (val >> BCM2835_GPIO_COMMON_SHIFT(gpio)) & 0x1;
}
static int bcm2835_gpio_get_value(struct udevice *dev, unsigned gpio)
{
const struct bcm2835_gpios *gpios = dev_get_priv(dev);
return bcm2835_get_value(gpios, gpio);
}
static int bcm2835_gpio_set_value(struct udevice *dev, unsigned gpio,
int value)
{
struct bcm2835_gpios *gpios = dev_get_priv(dev);
u32 *output_reg = value ? gpios->reg->gpset : gpios->reg->gpclr;
writel(1 << BCM2835_GPIO_COMMON_SHIFT(gpio),
&output_reg[BCM2835_GPIO_COMMON_BANK(gpio)]);
return 0;
}
static int bcm2835_gpio_get_function(struct udevice *dev, unsigned offset)
{
struct bcm2835_gpios *priv = dev_get_priv(dev);
int funcid;
funcid = pinctrl_get_gpio_mux(priv->pinctrl, 0, offset);
switch (funcid) {
case BCM2835_GPIO_OUTPUT:
return GPIOF_OUTPUT;
case BCM2835_GPIO_INPUT:
return GPIOF_INPUT;
default:
return GPIOF_FUNC;
}
}
static const struct dm_gpio_ops gpio_bcm2835_ops = {
.direction_input = bcm2835_gpio_direction_input,
.direction_output = bcm2835_gpio_direction_output,
.get_value = bcm2835_gpio_get_value,
.set_value = bcm2835_gpio_set_value,
.get_function = bcm2835_gpio_get_function,
};
static int bcm2835_gpio_probe(struct udevice *dev)
{
struct bcm2835_gpios *gpios = dev_get_priv(dev);
struct bcm2835_gpio_platdata *plat = dev_get_platdata(dev);
struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
uc_priv->bank_name = "GPIO";
uc_priv->gpio_count = BCM2835_GPIO_COUNT;
gpios->reg = (struct bcm2835_gpio_regs *)plat->base;
/* We know we're spawned by the pinctrl driver */
gpios->pinctrl = dev->parent;
return 0;
}
#if CONFIG_IS_ENABLED(OF_CONTROL)
static int bcm2835_gpio_ofdata_to_platdata(struct udevice *dev)
{
struct bcm2835_gpio_platdata *plat = dev_get_platdata(dev);
fdt_addr_t addr;
addr = devfdt_get_addr(dev);
if (addr == FDT_ADDR_T_NONE)
return -EINVAL;
plat->base = addr;
return 0;
}
#endif
U_BOOT_DRIVER(gpio_bcm2835) = {
.name = "gpio_bcm2835",
.id = UCLASS_GPIO,
.ofdata_to_platdata = of_match_ptr(bcm2835_gpio_ofdata_to_platdata),
.platdata_auto_alloc_size = sizeof(struct bcm2835_gpio_platdata),
.ops = &gpio_bcm2835_ops,
.probe = bcm2835_gpio_probe,
.flags = DM_FLAG_PRE_RELOC,
.priv_auto_alloc_size = sizeof(struct bcm2835_gpios),
};