From: Jarrett Schultz <[email protected]> Detect SPI HID devices described in Device Tree.
Signed-off-by: Dmitry Antipov <[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-of.c | 210 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 226 insertions(+) diff --git a/drivers/hid/spi-hid/Kconfig b/drivers/hid/spi-hid/Kconfig index 303ada03a1bf..63f202975ac3 100644 --- a/drivers/hid/spi-hid/Kconfig +++ b/drivers/hid/spi-hid/Kconfig @@ -26,6 +26,21 @@ config SPI_HID_ACPI will be called spi-hid-acpi. It will also build/depend on the module spi-hid. +config SPI_HID_OF + tristate "HID over SPI transport layer Open Firmware driver" + depends on OF + 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 Open Firmware (Device Tree)-based systems. + + If unsure, say N. + + This support is also available as a module. If so, the module + will be called spi-hid-of. 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 3ca326602643..31192e71edae 100644 --- a/drivers/hid/spi-hid/Makefile +++ b/drivers/hid/spi-hid/Makefile @@ -9,3 +9,4 @@ obj-$(CONFIG_SPI_HID_CORE) += spi-hid.o spi-hid-objs = spi-hid-core.o CFLAGS_spi-hid-core.o := -I$(src) obj-$(CONFIG_SPI_HID_ACPI) += spi-hid-acpi.o +obj-$(CONFIG_SPI_HID_OF) += spi-hid-of.o diff --git a/drivers/hid/spi-hid/spi-hid-of.c b/drivers/hid/spi-hid/spi-hid-of.c new file mode 100644 index 000000000000..d1bbdc17102e --- /dev/null +++ b/drivers/hid/spi-hid/spi-hid-of.c @@ -0,0 +1,210 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * HID over SPI protocol, Open Firmware related code + * + * Copyright (c) 2021 Microsoft Corporation + * + * 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/container_of.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/gpio/consumer.h> +#include <linux/module.h> +#include <linux/regulator/consumer.h> +#include <linux/spi/spi.h> +#include <linux/types.h> + +#include "spi-hid.h" + +/* Per-compatible data: protocol parameters and timings */ +struct spi_hid_of_data { + struct spi_hid_conf conf; + u32 post_power_on_delay_ms; + u32 minimal_reset_delay_ms; +}; + +/* Config structure is filled with match data and Device Tree resources */ +struct spi_hid_of_config { + struct spihid_ops ops; + + struct spi_hid_of_data data; + + struct gpio_desc *reset_gpio; + struct regulator *supply; + bool supply_enabled; +}; + +static const struct spi_hid_of_data microsoft_g6_data = { + .conf = { + .input_report_header_address = 0x1000, + .input_report_body_address = 0x1004, + .output_report_address = 0x2000, + .read_opcode = 0x0b, + .write_opcode = 0x02, + }, + .post_power_on_delay_ms = 10, + .minimal_reset_delay_ms = 100, +}; + +static int spi_hid_of_populate_config(struct spi_hid_of_config *conf, + struct device *dev) +{ + conf->supply = devm_regulator_get(dev, "vdd"); + if (IS_ERR(conf->supply)) + return dev_err_probe(dev, PTR_ERR(conf->supply), + "Failed to get regulator\n"); + conf->supply_enabled = false; + + conf->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(conf->reset_gpio)) + return dev_err_probe(dev, PTR_ERR(conf->reset_gpio), + "Failed to get reset GPIO\n"); + + return 0; +} + +static int spi_hid_of_power_down(struct spihid_ops *ops) +{ + struct spi_hid_of_config *conf = container_of(ops, + struct spi_hid_of_config, + ops); + int error; + + if (!conf->supply_enabled) + return 0; + + error = regulator_disable(conf->supply); + if (error == 0) + conf->supply_enabled = false; + + return error; +} + +static int spi_hid_of_power_up(struct spihid_ops *ops) +{ + struct spi_hid_of_config *conf = container_of(ops, + struct spi_hid_of_config, + ops); + int error; + + if (conf->supply_enabled) + return 0; + + error = regulator_enable(conf->supply); + + if (error == 0) { + conf->supply_enabled = true; + fsleep(1000 * conf->data.post_power_on_delay_ms); + } + + return error; +} + +static int spi_hid_of_assert_reset(struct spihid_ops *ops) +{ + struct spi_hid_of_config *conf = container_of(ops, + struct spi_hid_of_config, + ops); + + return gpiod_set_value_cansleep(conf->reset_gpio, 1); +} + +static int spi_hid_of_deassert_reset(struct spihid_ops *ops) +{ + struct spi_hid_of_config *conf = container_of(ops, + struct spi_hid_of_config, + ops); + + return gpiod_set_value_cansleep(conf->reset_gpio, 0); +} + +static void spi_hid_of_sleep_minimal_reset_delay(struct spihid_ops *ops) +{ + struct spi_hid_of_config *conf = container_of(ops, + struct spi_hid_of_config, + ops); + fsleep(1000 * conf->data.minimal_reset_delay_ms); +} + +static int spi_hid_of_probe(struct spi_device *spi) +{ + struct device *dev = &spi->dev; + const struct spi_hid_of_data *data; + struct spi_hid_of_config *config; + int error; + + config = devm_kzalloc(dev, sizeof(struct spi_hid_of_config), + GFP_KERNEL); + if (!config) + return -ENOMEM; + + config->ops.power_up = spi_hid_of_power_up; + config->ops.power_down = spi_hid_of_power_down; + config->ops.assert_reset = spi_hid_of_assert_reset; + config->ops.deassert_reset = spi_hid_of_deassert_reset; + config->ops.sleep_minimal_reset_delay = + spi_hid_of_sleep_minimal_reset_delay; + + data = spi_get_device_match_data(spi); + if (!data) + return dev_err_probe(dev, -ENODEV, "No match data\n"); + + config->data = *data; + + /* + * FIXME: multi-SPI not supported. Once it is, derive the + * HID-over-SPI flags from spi->mode. + */ + + error = spi_hid_of_populate_config(config, dev); + if (error) + return dev_err_probe(dev, error, "Unable to populate config data\n"); + + return spi_hid_core_probe(spi, &config->ops, &config->data.conf); +} + +static const struct of_device_id spi_hid_of_match[] = { + { .compatible = "microsoft,g6-touch-digitizer", .data = µsoft_g6_data }, + { } +}; +MODULE_DEVICE_TABLE(of, spi_hid_of_match); + +static const struct spi_device_id spi_hid_of_id_table[] = { + { .name = "g6-touch-digitizer", .driver_data = (kernel_ulong_t)µsoft_g6_data }, + { } +}; +MODULE_DEVICE_TABLE(spi, spi_hid_of_id_table); + +static struct spi_driver spi_hid_of_driver = { + .driver = { + .name = "spi_hid_of", + .owner = THIS_MODULE, + .of_match_table = spi_hid_of_match, + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + }, + .probe = spi_hid_of_probe, + .remove = spi_hid_core_remove, + .id_table = spi_hid_of_id_table, +}; + +module_spi_driver(spi_hid_of_driver); + +MODULE_DESCRIPTION("HID over SPI OF transport driver"); +MODULE_AUTHOR("Dmitry Antipov <[email protected]>"); +MODULE_LICENSE("GPL"); -- 2.56.0.257.gf7497c7d27-goog
