Add a board driver for the upcoming gdsys Gazerbeam board.
Signed-off-by: Mario Six mario.six@gdsys.cc
---
v2 -> v3: * Set startup-finished GPIOs during probe * Added driver binding file for gazerbeam board * Improved error handling * Improved error/debug output * Improved documentation * Turned magic numbers into named constants
v1 -> v2: * Improved error handling * Renamed DT properties * Moved the driver over to the board uclass
--- .../bindings/board/gdsys,board_gazerbeam.txt | 46 ++++ drivers/board/gazerbeam.c | 262 +++++++++++++++++++++ drivers/board/gazerbeam.h | 18 ++ 3 files changed, 326 insertions(+) create mode 100644 Documentation/devicetree/bindings/board/gdsys,board_gazerbeam.txt create mode 100644 drivers/board/gazerbeam.c create mode 100644 drivers/board/gazerbeam.h
diff --git a/Documentation/devicetree/bindings/board/gdsys,board_gazerbeam.txt b/Documentation/devicetree/bindings/board/gdsys,board_gazerbeam.txt new file mode 100644 index 0000000000..28c1080d90 --- /dev/null +++ b/Documentation/devicetree/bindings/board/gdsys,board_gazerbeam.txt @@ -0,0 +1,46 @@ +gdsys Gazerbeam board driver + +This driver provides capabilities to access the gdsys Gazerbeam board's device +information. Furthermore, phandles to some internal devices are provided for +the board files. + +Required properties: +- compatible: should be "gdsys,board_gazerbeam" +- csb: phandle to the board's coherent system bus (CSB) device node +- rxaui[0-3]: phandles to the rxaui control device nodes +- fpga[0-1]: phandles to the board's gdsys FPGA device nodes +- ioep[0-1]: phandles to the board's IO endpoint device nodes +- ver-gpios: GPIO list to read the hardware version from +- var-gpios: GPIO list to read the hardware variant information from +- reset-gpios: GPIO list for the board's reset GPIOs + +Example: + + +board { + compatible = "gdsys,board_gazerbeam"; + csb = <&board_soc>; + serdes = <&SERDES>; + rxaui0 = <&RXAUI0>; + rxaui1 = <&RXAUI1>; + rxaui2 = <&RXAUI2>; + rxaui3 = <&RXAUI3>; + fpga0 = <&FPGA0>; + fpga1 = <&FPGA1>; + ioep0 = <&IOEP0>; + ioep1 = <&IOEP1>; + + ver-gpios = <&PPCPCA 12 0 + &PPCPCA 13 0 + &PPCPCA 14 0 + &PPCPCA 15 0>; + + /* MC2/SC-Board */ + var-gpios-mc2 = <&GPIO_VB0 0 0 /* VAR-MC_SC */ + &GPIO_VB0 11 0>; /* VAR-CON */ + /* MC4-Board */ + var-gpios-mc4 = <&GPIO_VB1 0 0 /* VAR-MC_SC */ + &GPIO_VB1 11 0>; /* VAR-CON */ + + reset-gpios = <&gpio0 1 0 &gpio0 2 1>; +}; diff --git a/drivers/board/gazerbeam.c b/drivers/board/gazerbeam.c new file mode 100644 index 0000000000..481cce8e80 --- /dev/null +++ b/drivers/board/gazerbeam.c @@ -0,0 +1,262 @@ +// 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, 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, +}; diff --git a/drivers/board/gazerbeam.h b/drivers/board/gazerbeam.h new file mode 100644 index 0000000000..0ca003a373 --- /dev/null +++ b/drivers/board/gazerbeam.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * (C) Copyright 2017 + * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +enum { + BOARD_MULTICHANNEL, + BOARD_VARIANT, + BOARD_HWVERSION, +}; + +enum { + VAR_CON, + VAR_CPU, +}; -- 2.11.0