hid.c

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/* SPDX-License-Identifier: GPL-2.0-only */
 
#include <acpi/acpigen_dsm.h>
#include <acpi/acpi_device.h>
#include <assert.h>
#include <device/device.h>
#include <string.h>
#include "chip.h"
#include <gpio.h>
#include <console/console.h>
 
#if CONFIG(HAVE_ACPI_TABLES)
static void i2c_hid_fill_dsm(const struct device *dev)
{
        struct drivers_i2c_hid_config *config = dev->chip_info;
        struct dsm_i2c_hid_config dsm_config = {
                .hid_desc_reg_offset = config->hid_desc_reg_offset,
        };
 
        acpigen_write_dsm_i2c_hid(&dsm_config);
}
 
static void i2c_hid_fill_ssdt_generator(const struct device *dev)
{
        struct drivers_i2c_hid_config *config = dev->chip_info;
        config->generic.cid = I2C_HID_CID;
        i2c_generic_fill_ssdt(dev, &i2c_hid_fill_dsm, &config->generic);
}
 
static const char *i2c_hid_acpi_name(const struct device *dev)
{
        static char name[5];
        struct drivers_i2c_hid_config *config = dev->chip_info;
        if (config->generic.name)
                return config->generic.name;
 
        snprintf(name, sizeof(name), "H%03.3X", dev->path.i2c.device);
        name[4] = '\0';
        return name;
}
#endif
 
static struct device_operations i2c_hid_ops = {
        .read_resources         = noop_read_resources,
        .set_resources          = noop_set_resources,
#if CONFIG(HAVE_ACPI_TABLES)
        .acpi_name              = i2c_hid_acpi_name,
        .acpi_fill_ssdt         = i2c_hid_fill_ssdt_generator,
#endif
};
 
static void i2c_hid_enable(struct device *dev)
{
        struct drivers_i2c_hid_config *config = dev->chip_info;
 
        if (!config)
                return;
 
        /* Check if device is present by reading GPIO */
        if (config->generic.device_present_gpio) {
                int present = gpio_get(config->generic.device_present_gpio);
                present ^= config->generic.device_present_gpio_invert;
 
                printk(BIOS_INFO, "%s is %spresent\n",
                       dev->chip_ops->name, present ? "" : "not ");
 
                if (!present) {
                        dev->enabled = 0;
                        return;
                }
        }
 
        /*
         * Ensure that I2C HID devices use level triggered interrupts as per ACPI
         * I2C HID requirement. Check interrupt and GPIO interrupt.
         */
        if ((!config->generic.irq_gpio.pin_count &&
              config->generic.irq.mode != ACPI_IRQ_LEVEL_TRIGGERED) ||
            (config->generic.irq_gpio.pin_count &&
             config->generic.irq_gpio.irq.mode != ACPI_IRQ_LEVEL_TRIGGERED)) {
                printk(BIOS_ERR, "%s IRQ is not level triggered.\n", config->generic.hid);
                BUG();
        }
 
        dev->ops = &i2c_hid_ops;
 
        if (config && config->generic.desc) {
                dev->name = config->generic.desc;
        }
}
 
struct chip_operations drivers_i2c_hid_ops = {
        CHIP_NAME("I2C HID Device")
        .enable_dev = i2c_hid_enable
};