u-boot/drivers/gpio/tegra_gpio.c
Marcel Ziswiler 1c1786d4c5 tegra: gpio: fix null label regression
Fix Tegra GPIO driver to not crash resp. misbehave upon requesting
GPIOs with an empty aka NULL label. As the driver uses exclusively the
label to check for reservation status actually supplying one is
mandatory!

This fixes a regression introduced by commit:

2fccd2d96b
tegra: Convert tegra GPIO driver to use driver model

Signed-off-by: Marcel Ziswiler <marcel@ziswiler.com>
Acked-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2014-10-22 09:30:55 -07:00

486 lines
12 KiB
C

/*
* NVIDIA Tegra20 GPIO handling.
* (C) Copyright 2010-2012
* NVIDIA Corporation <www.nvidia.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
/*
* Based on (mostly copied from) kw_gpio.c based Linux 2.6 kernel driver.
* Tom Warren (twarren@nvidia.com)
*/
#include <common.h>
#include <dm.h>
#include <malloc.h>
#include <errno.h>
#include <fdtdec.h>
#include <asm/io.h>
#include <asm/bitops.h>
#include <asm/arch/tegra.h>
#include <asm/gpio.h>
#include <dm/device-internal.h>
DECLARE_GLOBAL_DATA_PTR;
enum {
TEGRA_CMD_INFO,
TEGRA_CMD_PORT,
TEGRA_CMD_OUTPUT,
TEGRA_CMD_INPUT,
};
struct tegra_gpio_platdata {
struct gpio_ctlr_bank *bank;
const char *port_name; /* Name of port, e.g. "B" */
int base_gpio; /* Port number for this port (0, 1,.., n-1) */
};
/* Information about each port at run-time */
struct tegra_port_info {
char label[TEGRA_GPIOS_PER_PORT][GPIO_NAME_SIZE];
struct gpio_ctlr_bank *bank;
int base_gpio; /* Port number for this port (0, 1,.., n-1) */
};
/* Return config of pin 'gpio' as GPIO (1) or SFPIO (0) */
static int get_config(unsigned gpio)
{
struct gpio_ctlr *ctlr = (struct gpio_ctlr *)NV_PA_GPIO_BASE;
struct gpio_ctlr_bank *bank = &ctlr->gpio_bank[GPIO_BANK(gpio)];
u32 u;
int type;
u = readl(&bank->gpio_config[GPIO_PORT(gpio)]);
type = (u >> GPIO_BIT(gpio)) & 1;
debug("get_config: port = %d, bit = %d is %s\n",
GPIO_FULLPORT(gpio), GPIO_BIT(gpio), type ? "GPIO" : "SFPIO");
return type;
}
/* Config pin 'gpio' as GPIO or SFPIO, based on 'type' */
static void set_config(unsigned gpio, int type)
{
struct gpio_ctlr *ctlr = (struct gpio_ctlr *)NV_PA_GPIO_BASE;
struct gpio_ctlr_bank *bank = &ctlr->gpio_bank[GPIO_BANK(gpio)];
u32 u;
debug("set_config: port = %d, bit = %d, %s\n",
GPIO_FULLPORT(gpio), GPIO_BIT(gpio), type ? "GPIO" : "SFPIO");
u = readl(&bank->gpio_config[GPIO_PORT(gpio)]);
if (type) /* GPIO */
u |= 1 << GPIO_BIT(gpio);
else
u &= ~(1 << GPIO_BIT(gpio));
writel(u, &bank->gpio_config[GPIO_PORT(gpio)]);
}
/* Return GPIO pin 'gpio' direction - 0 = input or 1 = output */
static int get_direction(unsigned gpio)
{
struct gpio_ctlr *ctlr = (struct gpio_ctlr *)NV_PA_GPIO_BASE;
struct gpio_ctlr_bank *bank = &ctlr->gpio_bank[GPIO_BANK(gpio)];
u32 u;
int dir;
u = readl(&bank->gpio_dir_out[GPIO_PORT(gpio)]);
dir = (u >> GPIO_BIT(gpio)) & 1;
debug("get_direction: port = %d, bit = %d, %s\n",
GPIO_FULLPORT(gpio), GPIO_BIT(gpio), dir ? "OUT" : "IN");
return dir;
}
/* Config GPIO pin 'gpio' as input or output (OE) as per 'output' */
static void set_direction(unsigned gpio, int output)
{
struct gpio_ctlr *ctlr = (struct gpio_ctlr *)NV_PA_GPIO_BASE;
struct gpio_ctlr_bank *bank = &ctlr->gpio_bank[GPIO_BANK(gpio)];
u32 u;
debug("set_direction: port = %d, bit = %d, %s\n",
GPIO_FULLPORT(gpio), GPIO_BIT(gpio), output ? "OUT" : "IN");
u = readl(&bank->gpio_dir_out[GPIO_PORT(gpio)]);
if (output)
u |= 1 << GPIO_BIT(gpio);
else
u &= ~(1 << GPIO_BIT(gpio));
writel(u, &bank->gpio_dir_out[GPIO_PORT(gpio)]);
}
/* set GPIO pin 'gpio' output bit as 0 or 1 as per 'high' */
static void set_level(unsigned gpio, int high)
{
struct gpio_ctlr *ctlr = (struct gpio_ctlr *)NV_PA_GPIO_BASE;
struct gpio_ctlr_bank *bank = &ctlr->gpio_bank[GPIO_BANK(gpio)];
u32 u;
debug("set_level: port = %d, bit %d == %d\n",
GPIO_FULLPORT(gpio), GPIO_BIT(gpio), high);
u = readl(&bank->gpio_out[GPIO_PORT(gpio)]);
if (high)
u |= 1 << GPIO_BIT(gpio);
else
u &= ~(1 << GPIO_BIT(gpio));
writel(u, &bank->gpio_out[GPIO_PORT(gpio)]);
}
static int check_reserved(struct udevice *dev, unsigned offset,
const char *func)
{
struct tegra_port_info *state = dev_get_priv(dev);
struct gpio_dev_priv *uc_priv = dev->uclass_priv;
if (!*state->label[offset]) {
printf("tegra_gpio: %s: error: gpio %s%d not reserved\n",
func, uc_priv->bank_name, offset);
return -EBUSY;
}
return 0;
}
/* set GPIO pin 'gpio' as an output, with polarity 'value' */
int tegra_spl_gpio_direction_output(int gpio, int value)
{
/* Configure as a GPIO */
set_config(gpio, 1);
/* Configure GPIO output value. */
set_level(gpio, value);
/* Configure GPIO direction as output. */
set_direction(gpio, 1);
return 0;
}
/*
* Generic_GPIO primitives.
*/
static int tegra_gpio_request(struct udevice *dev, unsigned offset,
const char *label)
{
struct tegra_port_info *state = dev_get_priv(dev);
if (!label)
return -EINVAL;
if (*state->label[offset])
return -EBUSY;
strncpy(state->label[offset], label, GPIO_NAME_SIZE);
state->label[offset][GPIO_NAME_SIZE - 1] = '\0';
/* Configure as a GPIO */
set_config(state->base_gpio + offset, 1);
return 0;
}
static int tegra_gpio_free(struct udevice *dev, unsigned offset)
{
struct tegra_port_info *state = dev_get_priv(dev);
int ret;
ret = check_reserved(dev, offset, __func__);
if (ret)
return ret;
state->label[offset][0] = '\0';
return 0;
}
/* read GPIO OUT value of pin 'gpio' */
static int tegra_gpio_get_output_value(unsigned gpio)
{
struct gpio_ctlr *ctlr = (struct gpio_ctlr *)NV_PA_GPIO_BASE;
struct gpio_ctlr_bank *bank = &ctlr->gpio_bank[GPIO_BANK(gpio)];
int val;
debug("gpio_get_output_value: pin = %d (port %d:bit %d)\n",
gpio, GPIO_FULLPORT(gpio), GPIO_BIT(gpio));
val = readl(&bank->gpio_out[GPIO_PORT(gpio)]);
return (val >> GPIO_BIT(gpio)) & 1;
}
/* set GPIO pin 'gpio' as an input */
static int tegra_gpio_direction_input(struct udevice *dev, unsigned offset)
{
struct tegra_port_info *state = dev_get_priv(dev);
int ret;
ret = check_reserved(dev, offset, __func__);
if (ret)
return ret;
/* Configure GPIO direction as input. */
set_direction(state->base_gpio + offset, 0);
return 0;
}
/* set GPIO pin 'gpio' as an output, with polarity 'value' */
static int tegra_gpio_direction_output(struct udevice *dev, unsigned offset,
int value)
{
struct tegra_port_info *state = dev_get_priv(dev);
int gpio = state->base_gpio + offset;
int ret;
ret = check_reserved(dev, offset, __func__);
if (ret)
return ret;
/* Configure GPIO output value. */
set_level(gpio, value);
/* Configure GPIO direction as output. */
set_direction(gpio, 1);
return 0;
}
/* read GPIO IN value of pin 'gpio' */
static int tegra_gpio_get_value(struct udevice *dev, unsigned offset)
{
struct tegra_port_info *state = dev_get_priv(dev);
int gpio = state->base_gpio + offset;
int ret;
int val;
ret = check_reserved(dev, offset, __func__);
if (ret)
return ret;
debug("%s: pin = %d (port %d:bit %d)\n", __func__,
gpio, GPIO_FULLPORT(gpio), GPIO_BIT(gpio));
val = readl(&state->bank->gpio_in[GPIO_PORT(gpio)]);
return (val >> GPIO_BIT(gpio)) & 1;
}
/* write GPIO OUT value to pin 'gpio' */
static int tegra_gpio_set_value(struct udevice *dev, unsigned offset, int value)
{
struct tegra_port_info *state = dev_get_priv(dev);
int gpio = state->base_gpio + offset;
int ret;
ret = check_reserved(dev, offset, __func__);
if (ret)
return ret;
debug("gpio_set_value: pin = %d (port %d:bit %d), value = %d\n",
gpio, GPIO_FULLPORT(gpio), GPIO_BIT(gpio), value);
/* Configure GPIO output value. */
set_level(gpio, value);
return 0;
}
void gpio_config_table(const struct tegra_gpio_config *config, int len)
{
int i;
for (i = 0; i < len; i++) {
switch (config[i].init) {
case TEGRA_GPIO_INIT_IN:
gpio_direction_input(config[i].gpio);
break;
case TEGRA_GPIO_INIT_OUT0:
gpio_direction_output(config[i].gpio, 0);
break;
case TEGRA_GPIO_INIT_OUT1:
gpio_direction_output(config[i].gpio, 1);
break;
}
set_config(config[i].gpio, 1);
}
}
static int tegra_gpio_get_function(struct udevice *dev, unsigned offset)
{
struct tegra_port_info *state = dev_get_priv(dev);
int gpio = state->base_gpio + offset;
if (!*state->label[offset])
return GPIOF_UNUSED;
if (!get_config(gpio))
return GPIOF_FUNC;
else if (get_direction(gpio))
return GPIOF_OUTPUT;
else
return GPIOF_INPUT;
}
static int tegra_gpio_get_state(struct udevice *dev, unsigned int offset,
char *buf, int bufsize)
{
struct gpio_dev_priv *uc_priv = dev->uclass_priv;
struct tegra_port_info *state = dev_get_priv(dev);
int gpio = state->base_gpio + offset;
const char *label;
int is_output;
int is_gpio;
int size;
label = state->label[offset];
is_gpio = get_config(gpio); /* GPIO, not SFPIO */
size = snprintf(buf, bufsize, "%s%d: ",
uc_priv->bank_name ? uc_priv->bank_name : "", offset);
buf += size;
bufsize -= size;
if (is_gpio) {
is_output = get_direction(gpio);
snprintf(buf, bufsize, "%s: %d [%c]%s%s",
is_output ? "out" : " in",
is_output ?
tegra_gpio_get_output_value(gpio) :
tegra_gpio_get_value(dev, offset),
*label ? 'x' : ' ',
*label ? " " : "",
label);
} else {
snprintf(buf, bufsize, "sfpio");
}
return 0;
}
static const struct dm_gpio_ops gpio_tegra_ops = {
.request = tegra_gpio_request,
.free = tegra_gpio_free,
.direction_input = tegra_gpio_direction_input,
.direction_output = tegra_gpio_direction_output,
.get_value = tegra_gpio_get_value,
.set_value = tegra_gpio_set_value,
.get_function = tegra_gpio_get_function,
.get_state = tegra_gpio_get_state,
};
/**
* Returns the name of a GPIO port
*
* GPIOs are named A, B, C, ..., Z, AA, BB, CC, ...
*
* @base_port: Base port number (0, 1..n-1)
* @return allocated string containing the name
*/
static char *gpio_port_name(int base_port)
{
char *name, *s;
name = malloc(3);
if (name) {
s = name;
*s++ = 'A' + (base_port % 26);
if (base_port >= 26)
*s++ = *name;
*s = '\0';
}
return name;
}
static const struct udevice_id tegra_gpio_ids[] = {
{ .compatible = "nvidia,tegra30-gpio" },
{ .compatible = "nvidia,tegra20-gpio" },
{ }
};
static int gpio_tegra_probe(struct udevice *dev)
{
struct gpio_dev_priv *uc_priv = dev->uclass_priv;
struct tegra_port_info *priv = dev->priv;
struct tegra_gpio_platdata *plat = dev->platdata;
/* Only child devices have ports */
if (!plat)
return 0;
priv->bank = plat->bank;
priv->base_gpio = plat->base_gpio;
uc_priv->gpio_count = TEGRA_GPIOS_PER_PORT;
uc_priv->bank_name = plat->port_name;
return 0;
}
/**
* We have a top-level GPIO device with no actual GPIOs. It has a child
* device for each Tegra port.
*/
static int gpio_tegra_bind(struct udevice *parent)
{
struct tegra_gpio_platdata *plat = parent->platdata;
struct gpio_ctlr *ctlr;
int bank_count;
int bank;
int ret;
int len;
/* If this is a child device, there is nothing to do here */
if (plat)
return 0;
/*
* This driver does not make use of interrupts, other than to figure
* out the number of GPIO banks
*/
if (!fdt_getprop(gd->fdt_blob, parent->of_offset, "interrupts", &len))
return -EINVAL;
bank_count = len / 3 / sizeof(u32);
ctlr = (struct gpio_ctlr *)fdtdec_get_addr(gd->fdt_blob,
parent->of_offset, "reg");
for (bank = 0; bank < bank_count; bank++) {
int port;
for (port = 0; port < TEGRA_PORTS_PER_BANK; port++) {
struct tegra_gpio_platdata *plat;
struct udevice *dev;
int base_port;
plat = calloc(1, sizeof(*plat));
if (!plat)
return -ENOMEM;
plat->bank = &ctlr->gpio_bank[bank];
base_port = bank * TEGRA_PORTS_PER_BANK + port;
plat->base_gpio = TEGRA_GPIOS_PER_PORT * base_port;
plat->port_name = gpio_port_name(base_port);
ret = device_bind(parent, parent->driver,
plat->port_name, plat, -1, &dev);
if (ret)
return ret;
dev->of_offset = parent->of_offset;
}
}
return 0;
}
U_BOOT_DRIVER(gpio_tegra) = {
.name = "gpio_tegra",
.id = UCLASS_GPIO,
.of_match = tegra_gpio_ids,
.bind = gpio_tegra_bind,
.probe = gpio_tegra_probe,
.priv_auto_alloc_size = sizeof(struct tegra_port_info),
.ops = &gpio_tegra_ops,
};