From: Angela Czubak <[email protected]> Detect SPI HID devices described in ACPI.
Signed-off-by: Angela Czubak <[email protected]> Reviewed-by: Dmitry Torokhov <[email protected]> Signed-off-by: Jingyuan Liang <[email protected]> --- drivers/hid/spi-hid/Kconfig | 15 +++ drivers/hid/spi-hid/Makefile | 1 + drivers/hid/spi-hid/spi-hid-acpi.c | 253 +++++++++++++++++++++++++++++++++++++ drivers/hid/spi-hid/spi-hid-core.c | 26 +--- drivers/hid/spi-hid/spi-hid.h | 45 +++++++ 5 files changed, 315 insertions(+), 25 deletions(-) diff --git a/drivers/hid/spi-hid/Kconfig b/drivers/hid/spi-hid/Kconfig index 836fdefe8345..114b1e00da39 100644 --- a/drivers/hid/spi-hid/Kconfig +++ b/drivers/hid/spi-hid/Kconfig @@ -10,6 +10,21 @@ menuconfig SPI_HID if SPI_HID +config SPI_HID_ACPI + tristate "HID over SPI transport layer ACPI driver" + depends on ACPI + select SPI_HID_CORE + help + Say Y here if you use a keyboard, a touchpad, a touchscreen, or any + other HID based devices which are connected to your computer via SPI. + This driver supports ACPI-based systems. + + If unsure, say N. + + This support is also available as a module. If so, the module + will be called spi-hid-acpi. It will also build/depend on the + module spi-hid. + config SPI_HID_CORE tristate endif diff --git a/drivers/hid/spi-hid/Makefile b/drivers/hid/spi-hid/Makefile index 733e006df56e..3ca326602643 100644 --- a/drivers/hid/spi-hid/Makefile +++ b/drivers/hid/spi-hid/Makefile @@ -8,3 +8,4 @@ obj-$(CONFIG_SPI_HID_CORE) += spi-hid.o spi-hid-objs = spi-hid-core.o CFLAGS_spi-hid-core.o := -I$(src) +obj-$(CONFIG_SPI_HID_ACPI) += spi-hid-acpi.o diff --git a/drivers/hid/spi-hid/spi-hid-acpi.c b/drivers/hid/spi-hid/spi-hid-acpi.c new file mode 100644 index 000000000000..298e3ba44d8a --- /dev/null +++ b/drivers/hid/spi-hid/spi-hid-acpi.c @@ -0,0 +1,253 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * HID over SPI protocol, ACPI related code + * + * Copyright (c) 2021 Microsoft Corporation + * Copyright (c) 2026 Google LLC + * + * This code was forked out of the HID over SPI core code, which is partially + * based on "HID over I2C protocol implementation: + * + * Copyright (c) 2012 Benjamin Tissoires <[email protected]> + * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France + * Copyright (c) 2012 Red Hat, Inc + * + * which in turn is partially based on "USB HID support for Linux": + * + * Copyright (c) 1999 Andreas Gal + * Copyright (c) 2000-2005 Vojtech Pavlik <[email protected]> + * Copyright (c) 2005 Michael Haboustak <[email protected]> for Concept2, Inc + * Copyright (c) 2007-2008 Oliver Neukum + * Copyright (c) 2006-2010 Jiri Kosina + */ + +#include <linux/acpi.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/reset.h> +#include <linux/uuid.h> + +#include "spi-hid.h" + +/* Config structure is filled with data from ACPI */ +struct spi_hid_acpi_config { + struct spihid_ops ops; + + struct spi_hid_conf property_conf; + u32 post_power_on_delay_ms; + u32 minimal_reset_delay_ms; + struct acpi_device *adev; +}; + +/* HID SPI Device: 6e2ac436-0fcf41af-a265-b32a220dcfab */ +static guid_t spi_hid_guid = + GUID_INIT(0x6E2AC436, 0x0FCF, 0x41AF, + 0xA2, 0x65, 0xB3, 0x2A, 0x22, 0x0D, 0xCF, 0xAB); + +static int spi_hid_acpi_populate_config(struct spi_hid_acpi_config *conf, + struct acpi_device *adev) +{ + acpi_handle handle = acpi_device_handle(adev); + union acpi_object *obj; + + conf->adev = adev; + + /* Revision 3 for HID over SPI V1, see specification. */ + obj = acpi_evaluate_dsm_typed(handle, &spi_hid_guid, 3, 1, NULL, + ACPI_TYPE_INTEGER); + if (!obj) { + acpi_handle_err(handle, + "Error _DSM call to get HID input report header address failed"); + return -ENODEV; + } + conf->property_conf.input_report_header_address = obj->integer.value; + ACPI_FREE(obj); + + obj = acpi_evaluate_dsm_typed(handle, &spi_hid_guid, 3, 2, NULL, + ACPI_TYPE_INTEGER); + if (!obj) { + acpi_handle_err(handle, + "Error _DSM call to get HID input report body address failed"); + return -ENODEV; + } + conf->property_conf.input_report_body_address = obj->integer.value; + ACPI_FREE(obj); + + obj = acpi_evaluate_dsm_typed(handle, &spi_hid_guid, 3, 3, NULL, + ACPI_TYPE_INTEGER); + if (!obj) { + acpi_handle_err(handle, + "Error _DSM call to get HID output report header address failed"); + return -ENODEV; + } + conf->property_conf.output_report_address = obj->integer.value; + ACPI_FREE(obj); + + obj = acpi_evaluate_dsm_typed(handle, &spi_hid_guid, 3, 4, NULL, + ACPI_TYPE_BUFFER); + if (!obj) { + acpi_handle_err(handle, + "Error _DSM call to get HID read opcode failed"); + return -ENODEV; + } + if (obj->buffer.length == 1) { + conf->property_conf.read_opcode = obj->buffer.pointer[0]; + } else { + acpi_handle_err(handle, + "Error _DSM call to get HID read opcode, too long buffer"); + ACPI_FREE(obj); + return -ENODEV; + } + ACPI_FREE(obj); + + obj = acpi_evaluate_dsm_typed(handle, &spi_hid_guid, 3, 5, NULL, + ACPI_TYPE_BUFFER); + if (!obj) { + acpi_handle_err(handle, + "Error _DSM call to get HID write opcode failed"); + return -ENODEV; + } + if (obj->buffer.length == 1) { + conf->property_conf.write_opcode = obj->buffer.pointer[0]; + } else { + acpi_handle_err(handle, + "Error _DSM call to get HID write opcode, too long buffer"); + ACPI_FREE(obj); + return -ENODEV; + } + ACPI_FREE(obj); + + /* Value not provided in ACPI,*/ + conf->post_power_on_delay_ms = 5; + conf->minimal_reset_delay_ms = 150; + + if (!acpi_has_method(handle, "_RST")) { + acpi_handle_err(handle, "No reset method for acpi handle"); + return -EINVAL; + } + + /* FIXME: not reading hid-over-spi-flags, multi-SPI not supported */ + + return 0; +} + +static int spi_hid_acpi_power_none(struct spihid_ops *ops) +{ + return 0; +} + +static int spi_hid_acpi_power_down(struct spihid_ops *ops) +{ + struct spi_hid_acpi_config *conf = container_of(ops, + struct spi_hid_acpi_config, + ops); + + return acpi_device_set_power(conf->adev, ACPI_STATE_D3); +} + +static int spi_hid_acpi_power_up(struct spihid_ops *ops) +{ + struct spi_hid_acpi_config *conf = container_of(ops, + struct spi_hid_acpi_config, + ops); + int error; + + error = acpi_device_set_power(conf->adev, ACPI_STATE_D0); + if (error) { + dev_err(&conf->adev->dev, "Error could not power up ACPI device: %d.", error); + return error; + } + + if (conf->post_power_on_delay_ms) + msleep(conf->post_power_on_delay_ms); + + return 0; +} + +static int spi_hid_acpi_assert_reset(struct spihid_ops *ops) +{ + return 0; +} + +static int spi_hid_acpi_deassert_reset(struct spihid_ops *ops) +{ + struct spi_hid_acpi_config *conf = container_of(ops, + struct spi_hid_acpi_config, + ops); + + return device_reset(&conf->adev->dev); +} + +static void spi_hid_acpi_sleep_minimal_reset_delay(struct spihid_ops *ops) +{ + struct spi_hid_acpi_config *conf = container_of(ops, + struct spi_hid_acpi_config, + ops); + fsleep(1000 * conf->minimal_reset_delay_ms); +} + +static int spi_hid_acpi_probe(struct spi_device *spi) +{ + struct device *dev = &spi->dev; + struct acpi_device *adev; + struct spi_hid_acpi_config *config; + int error; + + adev = ACPI_COMPANION(dev); + if (!adev) { + dev_err(dev, "Error could not get ACPI device."); + return -ENODEV; + } + + config = devm_kzalloc(dev, sizeof(struct spi_hid_acpi_config), + GFP_KERNEL); + if (!config) + return -ENOMEM; + + if (acpi_device_power_manageable(adev)) { + config->ops.power_up = spi_hid_acpi_power_up; + config->ops.power_down = spi_hid_acpi_power_down; + } else { + config->ops.power_up = spi_hid_acpi_power_none; + config->ops.power_down = spi_hid_acpi_power_none; + } + config->ops.assert_reset = spi_hid_acpi_assert_reset; + config->ops.deassert_reset = spi_hid_acpi_deassert_reset; + config->ops.sleep_minimal_reset_delay = + spi_hid_acpi_sleep_minimal_reset_delay; + + error = spi_hid_acpi_populate_config(config, adev); + if (error) { + dev_err(dev, "%s: unable to populate config data.", __func__); + return error; + } + + return spi_hid_core_probe(spi, &config->ops, &config->property_conf); +} + +static const struct acpi_device_id spi_hid_acpi_match[] = { + { "ACPI0C51", 0 }, + { "PNP0C51", 0 }, + { } +}; +MODULE_DEVICE_TABLE(acpi, spi_hid_acpi_match); + +static struct spi_driver spi_hid_acpi_driver = { + .driver = { + .name = "spi_hid_acpi", + .owner = THIS_MODULE, + .acpi_match_table = spi_hid_acpi_match, + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + .dev_groups = spi_hid_groups, + }, + .probe = spi_hid_acpi_probe, + .remove = spi_hid_core_remove, +}; + +module_spi_driver(spi_hid_acpi_driver); + +MODULE_DESCRIPTION("HID over SPI ACPI transport driver"); +MODULE_AUTHOR("Angela Czubak <[email protected]>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/hid/spi-hid/spi-hid-core.c b/drivers/hid/spi-hid/spi-hid-core.c index 802615565541..d48175c764b9 100644 --- a/drivers/hid/spi-hid/spi-hid-core.c +++ b/drivers/hid/spi-hid/spi-hid-core.c @@ -43,6 +43,7 @@ #include <linux/wait.h> #include <linux/workqueue.h> +#include "spi-hid.h" #include "spi-hid-core.h" #define CREATE_TRACE_POINTS @@ -110,31 +111,6 @@ struct spi_hid_output_report { u8 *content; }; -/* struct spi_hid_conf - Conf provided to the core */ -struct spi_hid_conf { - u32 input_report_header_address; - u32 input_report_body_address; - u32 output_report_address; - u8 read_opcode; - u8 write_opcode; -}; - -/** - * struct spihid_ops - Ops provided to the core - * @power_up: do sequencing to power up the device - * @power_down: do sequencing to power down the device - * @assert_reset: do sequencing to assert the reset line - * @deassert_reset: do sequencing to deassert the reset line - * @sleep_minimal_reset_delay: minimal sleep delay during reset - */ -struct spihid_ops { - int (*power_up)(struct spihid_ops *ops); - int (*power_down)(struct spihid_ops *ops); - int (*assert_reset)(struct spihid_ops *ops); - int (*deassert_reset)(struct spihid_ops *ops); - void (*sleep_minimal_reset_delay)(struct spihid_ops *ops); -}; - static struct hid_ll_driver spi_hid_ll_driver; static void spi_hid_populate_read_approvals(const struct spi_hid_conf *conf, diff --git a/drivers/hid/spi-hid/spi-hid.h b/drivers/hid/spi-hid/spi-hid.h new file mode 100644 index 000000000000..f5a5f4d54beb --- /dev/null +++ b/drivers/hid/spi-hid/spi-hid.h @@ -0,0 +1,45 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2021 Microsoft Corporation + * Copyright (c) 2026 Google LLC + */ + +#ifndef SPI_HID_H +#define SPI_HID_H + +#include <linux/spi/spi.h> +#include <linux/sysfs.h> + +/* struct spi_hid_conf - Conf provided to the core */ +struct spi_hid_conf { + u32 input_report_header_address; + u32 input_report_body_address; + u32 output_report_address; + u8 read_opcode; + u8 write_opcode; +}; + +/** + * struct spihid_ops - Ops provided to the core + * @power_up: do sequencing to power up the device + * @power_down: do sequencing to power down the device + * @assert_reset: do sequencing to assert the reset line + * @deassert_reset: do sequencing to deassert the reset line + * @sleep_minimal_reset_delay: minimal sleep delay during reset + */ +struct spihid_ops { + int (*power_up)(struct spihid_ops *ops); + int (*power_down)(struct spihid_ops *ops); + int (*assert_reset)(struct spihid_ops *ops); + int (*deassert_reset)(struct spihid_ops *ops); + void (*sleep_minimal_reset_delay)(struct spihid_ops *ops); +}; + +int spi_hid_core_probe(struct spi_device *spi, struct spihid_ops *ops, + struct spi_hid_conf *conf); + +void spi_hid_core_remove(struct spi_device *spi); + +extern const struct attribute_group *spi_hid_groups[]; + +#endif /* SPI_HID_H */ -- 2.53.0.1185.g05d4b7b318-goog
