src/drivers/generic/gpio_keys/gpio_keys.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <acpi/acpi_device.h>
   4 #include <acpi/acpigen.h>
   5 #include <device/device.h>
   6 #include <stdio.h>
   7
   8 #include "chip.h"
   9
  10 static struct acpi_dp *gpio_keys_add_child_node(
  11                         struct drivers_generic_gpio_keys_config *config,
  12                         const char *parent_path)
  13 {
  14         struct key_info *key = &config->key;
  15         struct acpi_dp *dsd;
  16
  17         if (!key->dev_name || !key->linux_code)
  18                 return NULL;
  19
  20         dsd = acpi_dp_new_table(config->key.dev_name);
  21
  22         acpi_dp_add_integer(dsd, "linux,code", key->linux_code);
  23         if (key->linux_input_type)
  24                 acpi_dp_add_integer(dsd, "linux,input-type",
  25                                     key->linux_input_type);
  26         if (key->label)
  27                 acpi_dp_add_string(dsd, "label", key->label);
  28
  29         if (key->wakeup_route == WAKEUP_ROUTE_SCI)
  30                 acpigen_write_PRW(key->wake_gpe, 3);
  31
  32         if (key->wakeup_route != WAKEUP_ROUTE_DISABLED) {
  33                 acpi_dp_add_integer(dsd, "wakeup-source", 1);
  34                 acpi_dp_add_integer(dsd, "wakeup-event-action",
  35                                         key->wakeup_event_action);
  36         }
  37
  38         if (key->can_be_disabled)
  39                 acpi_dp_add_integer(dsd, "linux,can-disable",
  40                                     key->can_be_disabled);
  41         if (key->debounce_interval)
  42                 acpi_dp_add_integer(dsd, "debounce-interval",
  43                                     key->debounce_interval);
  44         acpi_dp_add_gpio(dsd, "gpios", parent_path, 0, 0,
  45                          config->gpio.active_low);
  46
  47         return dsd;
  48 }
  49
  50 static void gpio_keys_fill_ssdt_generator(const struct device *dev)
  51 {
  52         struct drivers_generic_gpio_keys_config *config = dev->chip_info;
  53         const char *scope = acpi_device_scope(dev);
  54         const char *path = acpi_device_path(dev);
  55         struct acpi_dp *dsd, *child;
  56         const char *drv_string = config->is_polled ? "gpio-keys-polled"
  57                                 : "gpio-keys";
  58
  59         if (!scope || !path || !config->gpio.pin_count)
  60                 return;
  61
  62         /* Device */
  63         acpigen_write_scope(scope);
  64         acpigen_write_device(acpi_device_name(dev));
  65
  66         /* _HID is set to PRP0001 */
  67         acpigen_write_name_string("_HID", ACPI_DT_NAMESPACE_HID);
  68
  69         /* Resources - _CRS */
  70         acpigen_write_name("_CRS");
  71         acpigen_write_resourcetemplate_header();
  72         acpi_device_write_gpio(&config->gpio);
  73         acpigen_write_resourcetemplate_footer();
  74
  75         /* DSD */
  76         dsd = acpi_dp_new_table("_DSD");
  77         acpi_dp_add_string(dsd, "compatible", drv_string);
  78         if (config->label)
  79                 acpi_dp_add_string(dsd, "label", config->label);
  80         if (config->is_polled)
  81                 acpi_dp_add_integer(dsd, "poll-interval",
  82                                         config->poll_interval);
  83         /* Child device defining key */
  84         child = gpio_keys_add_child_node(config, path);
  85         if (child)
  86                 acpi_dp_add_child(dsd, "button-0", child);
  87         acpi_dp_write(dsd);
  88
  89         acpigen_write_STA(acpi_device_status(dev));
  90
  91         acpigen_pop_len(); /* Device */
  92         acpigen_pop_len(); /* Scope */
  93 }
  94
  95 static const char *gpio_keys_acpi_name(const struct device *dev)
  96 {
  97         struct drivers_generic_gpio_keys_config *config = dev->chip_info;
  98         static char name[5];
  99
 100         if (config->name)
 101                 return config->name;
 102
 103         snprintf(name, sizeof(name), "K%03.3X", config->gpio.pins[0]);
 104         name[4] = '\0';
 105
 106         return name;
 107 }
 108
 109 static struct device_operations gpio_keys_ops = {
 110         .read_resources         = noop_read_resources,
 111         .set_resources          = noop_set_resources,
 112         .acpi_name              = gpio_keys_acpi_name,
 113         .acpi_fill_ssdt         = gpio_keys_fill_ssdt_generator,
 114 };
 115
 116 static void gpio_keys_enable(struct device *dev)
 117 {
 118         dev->ops = &gpio_keys_ops;
 119 }
 120
 121 struct chip_operations drivers_generic_gpio_keys_ops = {
 122         .name = "GPIO Keys",
 123         .enable_dev = gpio_keys_enable
 124 };