From 60f3217ed9a91bcf96a49af83fac3dcbaf54aa88 Mon Sep 17 00:00:00 2001 From: Furquan Shaikh Date: Mon, 12 Dec 2016 09:30:42 -0800 Subject: drivers/regulator: Add driver for handling GPIO-based fixed regulator This change adds the required device node in SSDT for defining GPIO-based fixed voltage regulator. BUG=chrome-os-partner:60194 BRANCH=None TEST=Verified that ELAN touchscreen works with exported GPIOs and ACPI regulator. Change-Id: I4380aea0929fb7e81dbe83f940e3e51e983819f9 Signed-off-by: Furquan Shaikh Reviewed-on: https://review.coreboot.org/17798 Tested-by: build bot (Jenkins) Reviewed-by: Duncan Laurie --- src/drivers/generic/gpio_regulator/Kconfig | 18 +++++ src/drivers/generic/gpio_regulator/Makefile.inc | 16 ++++ src/drivers/generic/gpio_regulator/chip.h | 27 +++++++ .../generic/gpio_regulator/gpio_regulator.c | 90 ++++++++++++++++++++++ 4 files changed, 151 insertions(+) create mode 100644 src/drivers/generic/gpio_regulator/Kconfig create mode 100644 src/drivers/generic/gpio_regulator/Makefile.inc create mode 100644 src/drivers/generic/gpio_regulator/chip.h create mode 100644 src/drivers/generic/gpio_regulator/gpio_regulator.c (limited to 'src/drivers') diff --git a/src/drivers/generic/gpio_regulator/Kconfig b/src/drivers/generic/gpio_regulator/Kconfig new file mode 100644 index 0000000000..12ab3cb223 --- /dev/null +++ b/src/drivers/generic/gpio_regulator/Kconfig @@ -0,0 +1,18 @@ +# +# This file is part of the coreboot project. +# +# Copyright 2016 Google Inc. +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; version 2 of the License. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# + +config DRIVERS_GENERIC_GPIO_REGULATOR + bool + depends on HAVE_ACPI_TABLES diff --git a/src/drivers/generic/gpio_regulator/Makefile.inc b/src/drivers/generic/gpio_regulator/Makefile.inc new file mode 100644 index 0000000000..845b19105a --- /dev/null +++ b/src/drivers/generic/gpio_regulator/Makefile.inc @@ -0,0 +1,16 @@ +# +# This file is part of the coreboot project. +# +# Copyright 2016 Google Inc. +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; version 2 of the License. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# + +ramstage-$(CONFIG_DRIVERS_GENERIC_GPIO_REGULATOR) += gpio_regulator.c diff --git a/src/drivers/generic/gpio_regulator/chip.h b/src/drivers/generic/gpio_regulator/chip.h new file mode 100644 index 0000000000..8d655ef6e5 --- /dev/null +++ b/src/drivers/generic/gpio_regulator/chip.h @@ -0,0 +1,27 @@ +/* + * This file is part of the coreboot project. + * + * Copyright 2016 Google Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#ifndef __DRIVERS_GENERIC_GPIO_REGULATOR_H__ +#define __DRIVERS_GENERIC_GPIO_REGULATOR_H__ + +#include + +struct drivers_generic_gpio_regulator_config { + const char *name; + struct acpi_gpio gpio; + bool enabled_on_boot; +}; + +#endif /* __DRIVERS_GENERIC_GPIO_REGULATOR_H__ */ diff --git a/src/drivers/generic/gpio_regulator/gpio_regulator.c b/src/drivers/generic/gpio_regulator/gpio_regulator.c new file mode 100644 index 0000000000..def174486c --- /dev/null +++ b/src/drivers/generic/gpio_regulator/gpio_regulator.c @@ -0,0 +1,90 @@ +/* + * This file is part of the coreboot project. + * + * Copyright 2016 Google Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include +#include +#include +#include + +#include "chip.h" + +static void gpio_regulator_fill_ssdt_generator(struct device *dev) +{ + struct drivers_generic_gpio_regulator_config *config = dev->chip_info; + const char *scope = acpi_device_scope(dev); + const char *path = acpi_device_path(dev); + struct acpi_dp *dsd; + + if (!dev->enabled || !scope || !path || !config->gpio.pin_count) + return; + + /* Device */ + acpigen_write_scope(scope); + acpigen_write_device(acpi_device_name(dev)); + + /* _HID is set to PRP0001 */ + acpigen_write_name_string("_HID", ACPI_DT_NAMESPACE_HID); + + /* Resources - _CRS */ + acpigen_write_name("_CRS"); + acpigen_write_resourcetemplate_header(); + acpi_device_write_gpio(&config->gpio); + acpigen_write_resourcetemplate_footer(); + + /* DSD */ + dsd = acpi_dp_new_table("_DSD"); + acpi_dp_add_string(dsd, "compatible", "regulator-fixed"); + acpi_dp_add_string(dsd, "regulator-name", config->name); + acpi_dp_add_gpio(dsd, "gpio-gpios", path, 0, 0, config->gpio.polarity); + if (config->enabled_on_boot) + acpi_dp_add_string(dsd, "regulator-boot-on", "on"); + if (config->gpio.polarity == ACPI_GPIO_ACTIVE_HIGH) + acpi_dp_add_string(dsd, "enable-active-high", "on"); + acpi_dp_write(dsd); + + acpigen_pop_len(); /* Device */ + acpigen_pop_len(); /* Scope */ +} + +static const char *gpio_regulator_acpi_name(struct device *dev) +{ + struct drivers_generic_gpio_regulator_config *config = dev->chip_info; + static char name[5]; + + snprintf(name, sizeof(name), "R%03.3X", config->gpio.pins[0]); + name[4] = '\0'; + + return name; +} + +static struct device_operations gpio_regulator_ops = { + .read_resources = DEVICE_NOOP, + .set_resources = DEVICE_NOOP, + .enable_resources = DEVICE_NOOP, + .acpi_name = &gpio_regulator_acpi_name, + .acpi_fill_ssdt_generator = &gpio_regulator_fill_ssdt_generator, +}; + +static void gpio_regulator_enable(struct device *dev) +{ + dev->ops = &gpio_regulator_ops; +} + +struct chip_operations drivers_generic_gpio_regulator_ops = { + CHIP_NAME("GPIO Regulator") + .enable_dev = &gpio_regulator_enable +}; -- cgit v1.2.3