// SPDX-License-Identifier: GPL-2.0+ /* * (C) Copyright 2017 * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc */ #include #include #include #include #include #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, 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 = !dm_i2c_probe(i2c_bus, MC2_EXPANDER_ADDR, 0, &dummy); mc4 = !dm_i2c_probe(i2c_bus, MC4_EXPANDER_ADDR, 0, &dummy); if (mc2 && mc4) { debug("%s: Board hardware configuration inconsistent.\n", dev->name); return -EINVAL; } listname = mc2 ? "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; } 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; } if ((sc && mc2) || (sc && mc4) || (!sc && !mc2 && !mc4)) { debug("%s: Board hardware configuration inconsistent.\n", dev->name); return -EINVAL; } 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, };