blob: 85de4e440cec551177a4aa772ec43d8013e5a87e [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2017
* Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc
*/
#include <common.h>
#include <dm.h>
#include <board.h>
#include <i2c.h>
#include <asm/gpio.h>
#include "gazerbeam.h"
/* Sequence number of I2C bus that holds the GPIO expanders */
static const int I2C_BUS_SEQ_NO = 1;
/* I2C address of SC/MC2 expander */
static const int MC2_EXPANDER_ADDR = 0x20;
/* I2C address of MC4 expander */
static const int MC4_EXPANDER_ADDR = 0x22;
/* Number of the GPIO to read the SC data from */
static const int SC_GPIO_NO;
/* Number of the GPIO to read the CON data from */
static const int CON_GPIO_NO = 1;
/**
* struct board_gazerbeam_priv - Private data structure for the gazerbeam board
* driver.
* @reset_gpios: GPIOs for the board's reset GPIOs.
* @var_gpios: GPIOs for the board's hardware variant GPIOs
* @ver_gpios: GPIOs for the board's hardware version GPIOs
* @variant: Container for the board's hardware variant (CON/CPU)
* @multichannel: Container for the board's multichannel variant (MC4/MC2/SC)
* @hwversion: Container for the board's hardware version
*/
struct board_gazerbeam_priv {
struct gpio_desc reset_gpios[2];
struct gpio_desc var_gpios[2];
struct gpio_desc ver_gpios[4];
int variant;
int multichannel;
int hwversion;
};
/**
* _read_board_variant_data() - Read variant information from the hardware.
* @dev: The board device for which to determine the multichannel and device
* type information.
*
* The data read from the board's hardware (mostly hard-wired GPIOs) is stored
* in the private data structure of the driver to be used by other driver
* methods.
*
* Return: 0 if OK, -ve on error.
*/
static int _read_board_variant_data(struct udevice *dev)
{
struct board_gazerbeam_priv *priv = dev_get_priv(dev);
struct udevice *i2c_bus;
struct udevice *dummy;
char *listname;
int mc4, mc2, sc, mc2_sc, con;
int gpio_num;
int res;
res = uclass_get_device_by_seq(UCLASS_I2C, I2C_BUS_SEQ_NO, &i2c_bus);
if (res) {
debug("%s: Could not get I2C bus %d (err = %d)\n",
dev->name, I2C_BUS_SEQ_NO, res);
return res;
}
if (!i2c_bus) {
debug("%s: Could not get I2C bus %d\n",
dev->name, I2C_BUS_SEQ_NO);
return -EIO;
}
mc2_sc = !dm_i2c_probe(i2c_bus, MC2_EXPANDER_ADDR, 0, &dummy);
mc4 = !dm_i2c_probe(i2c_bus, MC4_EXPANDER_ADDR, 0, &dummy);
if (mc2_sc && mc4) {
debug("%s: Board hardware configuration inconsistent.\n",
dev->name);
return -EINVAL;
}
listname = mc2_sc ? "var-gpios-mc2" : "var-gpios-mc4";
gpio_num = gpio_request_list_by_name(dev, listname, priv->var_gpios,
ARRAY_SIZE(priv->var_gpios),
GPIOD_IS_IN);
if (gpio_num < 0) {
debug("%s: Requesting gpio list %s failed (err = %d).\n",
dev->name, listname, gpio_num);
return gpio_num;
}
sc = dm_gpio_get_value(&priv->var_gpios[SC_GPIO_NO]);
if (sc < 0) {
debug("%s: Error while reading 'sc' GPIO (err = %d)",
dev->name, sc);
return sc;
}
mc2 = mc2_sc ? (sc ? 0 : 1) : 0;
if ((sc && mc2) || (sc && mc4) || (!sc && !mc2 && !mc4)) {
debug("%s: Board hardware configuration inconsistent.\n",
dev->name);
return -EINVAL;
}
con = dm_gpio_get_value(&priv->var_gpios[CON_GPIO_NO]);
if (con < 0) {
debug("%s: Error while reading 'con' GPIO (err = %d)",
dev->name, con);
return con;
}
priv->variant = con ? VAR_CON : VAR_CPU;
priv->multichannel = mc4 ? 4 : (mc2 ? 2 : (sc ? 1 : 0));
return 0;
}
/**
* _read_hwversion() - Read the hardware version from the board.
* @dev: The board device for which to read the hardware version.
*
* The hardware version read from the board (from hard-wired GPIOs) is stored
* in the private data structure of the driver to be used by other driver
* methods.
*
* Return: 0 if OK, -ve on error.
*/
static int _read_hwversion(struct udevice *dev)
{
struct board_gazerbeam_priv *priv = dev_get_priv(dev);
int res;
res = gpio_request_list_by_name(dev, "ver-gpios", priv->ver_gpios,
ARRAY_SIZE(priv->ver_gpios),
GPIOD_IS_IN);
if (res < 0) {
debug("%s: Error getting GPIO list 'ver-gpios' (err = %d)\n",
dev->name, res);
return -ENODEV;
}
res = dm_gpio_get_values_as_int(priv->ver_gpios,
ARRAY_SIZE(priv->ver_gpios));
if (res < 0) {
debug("%s: Error reading HW version from expander (err = %d)\n",
dev->name, res);
return res;
}
priv->hwversion = res;
res = gpio_free_list(dev, priv->ver_gpios, ARRAY_SIZE(priv->ver_gpios));
if (res < 0) {
debug("%s: Error freeing HW version GPIO list (err = %d)\n",
dev->name, res);
return res;
}
return 0;
}
static int board_gazerbeam_detect(struct udevice *dev)
{
int res;
res = _read_board_variant_data(dev);
if (res) {
debug("%s: Error reading multichannel variant (err = %d)\n",
dev->name, res);
return res;
}
res = _read_hwversion(dev);
if (res) {
debug("%s: Error reading hardware version (err = %d)\n",
dev->name, res);
return res;
}
return 0;
}
static int board_gazerbeam_get_int(struct udevice *dev, int id, int *val)
{
struct board_gazerbeam_priv *priv = dev_get_priv(dev);
switch (id) {
case BOARD_MULTICHANNEL:
*val = priv->multichannel;
break;
case BOARD_VARIANT:
*val = priv->variant;
break;
case BOARD_HWVERSION:
*val = priv->hwversion;
break;
default:
debug("%s: Integer value %d unknown\n", dev->name, id);
return -EINVAL;
}
return 0;
}
static const struct udevice_id board_gazerbeam_ids[] = {
{ .compatible = "gdsys,board_gazerbeam" },
{ /* sentinel */ }
};
static const struct board_ops board_gazerbeam_ops = {
.detect = board_gazerbeam_detect,
.get_int = board_gazerbeam_get_int,
};
static int board_gazerbeam_probe(struct udevice *dev)
{
struct board_gazerbeam_priv *priv = dev_get_priv(dev);
int gpio_num, i;
gpio_num = gpio_request_list_by_name(dev, "reset-gpios",
priv->reset_gpios,
ARRAY_SIZE(priv->reset_gpios),
GPIOD_IS_OUT);
if (gpio_num < 0) {
debug("%s: Error getting GPIO list 'reset-gpios' (err = %d)\n",
dev->name, gpio_num);
return gpio_num;
}
/* Set startup-finished GPIOs */
for (i = 0; i < ARRAY_SIZE(priv->reset_gpios); i++) {
int res = dm_gpio_set_value(&priv->reset_gpios[i], 0);
if (res) {
debug("%s: Error while setting GPIO %d (err = %d)\n",
dev->name, i, res);
return res;
}
}
return 0;
}
U_BOOT_DRIVER(board_gazerbeam) = {
.name = "board_gazerbeam",
.id = UCLASS_BOARD,
.of_match = board_gazerbeam_ids,
.ops = &board_gazerbeam_ops,
.priv_auto_alloc_size = sizeof(struct board_gazerbeam_priv),
.probe = board_gazerbeam_probe,
};