diff options
Diffstat (limited to 'drivers/input/misc/soc_button_array.c')
| -rw-r--r-- | drivers/input/misc/soc_button_array.c | 159 |
1 files changed, 158 insertions, 1 deletions
diff --git a/drivers/input/misc/soc_button_array.c b/drivers/input/misc/soc_button_array.c index b8769f6e3601..95b787a63560 100644 --- a/drivers/input/misc/soc_button_array.c +++ b/drivers/input/misc/soc_button_array.c @@ -138,6 +138,153 @@ err_free_mem: return ERR_PTR(error); } +static int soc_button_get_acpi_object_int(const union acpi_object *obj) +{ + if (obj->type != ACPI_TYPE_INTEGER) + return -1; + + return obj->integer.value; +} + +/* Parse a single ACPI0011 _DSD button descriptor */ +static int soc_button_parse_btn_desc(struct device *dev, + const union acpi_object *desc, + int collection_uid, + struct soc_button_info *info) +{ + int upage, usage; + + if (desc->type != ACPI_TYPE_PACKAGE || + desc->package.count != 5 || + /* First byte should be 1 (control) */ + soc_button_get_acpi_object_int(&desc->package.elements[0]) != 1 || + /* Third byte should be collection uid */ + soc_button_get_acpi_object_int(&desc->package.elements[2]) != + collection_uid) { + dev_err(dev, "Invalid ACPI Button Descriptor\n"); + return -ENODEV; + } + + info->event_type = EV_KEY; + info->acpi_index = + soc_button_get_acpi_object_int(&desc->package.elements[1]); + upage = soc_button_get_acpi_object_int(&desc->package.elements[3]); + usage = soc_button_get_acpi_object_int(&desc->package.elements[4]); + + /* + * The UUID: fa6bd625-9ce8-470d-a2c7-b3ca36c4282e descriptors use HID + * usage page and usage codes, but otherwise the device is not HID + * compliant: it uses one irq per button instead of generating HID + * input reports and some buttons should generate wakeups where as + * others should not, so we cannot use the HID subsystem. + * + * Luckily all devices only use a few usage page + usage combinations, + * so we can simply check for the known combinations here. + */ + if (upage == 0x01 && usage == 0x81) { + info->name = "power"; + info->event_code = KEY_POWER; + info->wakeup = true; + } else if (upage == 0x07 && usage == 0xe3) { + info->name = "home"; + info->event_code = KEY_HOMEPAGE; + info->wakeup = true; + } else if (upage == 0x0c && usage == 0xe9) { + info->name = "volume_up"; + info->event_code = KEY_VOLUMEUP; + info->autorepeat = true; + } else if (upage == 0x0c && usage == 0xea) { + info->name = "volume_down"; + info->event_code = KEY_VOLUMEDOWN; + info->autorepeat = true; + } else { + dev_warn(dev, "Unknown button index %d upage %02x usage %02x, ignoring\n", + info->acpi_index, upage, usage); + info->name = "unknown"; + info->event_code = KEY_RESERVED; + } + + return 0; +} + +/* ACPI0011 _DSD btns descriptors UUID: fa6bd625-9ce8-470d-a2c7-b3ca36c4282e */ +static const u8 btns_desc_uuid[16] = { + 0x25, 0xd6, 0x6b, 0xfa, 0xe8, 0x9c, 0x0d, 0x47, + 0xa2, 0xc7, 0xb3, 0xca, 0x36, 0xc4, 0x28, 0x2e +}; + +/* Parse ACPI0011 _DSD button descriptors */ +static struct soc_button_info *soc_button_get_button_info(struct device *dev) +{ + struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER }; + const union acpi_object *desc, *el0, *uuid, *btns_desc = NULL; + struct soc_button_info *button_info; + acpi_status status; + int i, btn, collection_uid = -1; + + status = acpi_evaluate_object_typed(ACPI_HANDLE(dev), "_DSD", NULL, + &buf, ACPI_TYPE_PACKAGE); + if (ACPI_FAILURE(status)) { + dev_err(dev, "ACPI _DSD object not found\n"); + return ERR_PTR(-ENODEV); + } + + /* Look for the Button Descriptors UUID */ + desc = buf.pointer; + for (i = 0; (i + 1) < desc->package.count; i += 2) { + uuid = &desc->package.elements[i]; + + if (uuid->type != ACPI_TYPE_BUFFER || + uuid->buffer.length != 16 || + desc->package.elements[i + 1].type != ACPI_TYPE_PACKAGE) { + break; + } + + if (memcmp(uuid->buffer.pointer, btns_desc_uuid, 16) == 0) { + btns_desc = &desc->package.elements[i + 1]; + break; + } + } + + if (!btns_desc) { + dev_err(dev, "ACPI Button Descriptors not found\n"); + return ERR_PTR(-ENODEV); + } + + /* The first package describes the collection */ + el0 = &btns_desc->package.elements[0]; + if (el0->type == ACPI_TYPE_PACKAGE && + el0->package.count == 5 && + /* First byte should be 0 (collection) */ + soc_button_get_acpi_object_int(&el0->package.elements[0]) == 0 && + /* Third byte should be 0 (top level collection) */ + soc_button_get_acpi_object_int(&el0->package.elements[2]) == 0) { + collection_uid = soc_button_get_acpi_object_int( + &el0->package.elements[1]); + } + if (collection_uid == -1) { + dev_err(dev, "Invalid Button Collection Descriptor\n"); + return ERR_PTR(-ENODEV); + } + + /* There are package.count - 1 buttons + 1 terminating empty entry */ + button_info = devm_kcalloc(dev, btns_desc->package.count, + sizeof(*button_info), GFP_KERNEL); + if (!button_info) + return ERR_PTR(-ENOMEM); + + /* Parse the button descriptors */ + for (i = 1, btn = 0; i < btns_desc->package.count; i++, btn++) { + if (soc_button_parse_btn_desc(dev, + &btns_desc->package.elements[i], + collection_uid, + &button_info[btn])) + return ERR_PTR(-ENODEV); + } + + return button_info; +} + static int soc_button_remove(struct platform_device *pdev) { struct soc_button_data *priv = platform_get_drvdata(pdev); @@ -165,7 +312,13 @@ static int soc_button_probe(struct platform_device *pdev) if (!id) return -ENODEV; - button_info = (struct soc_button_info *)id->driver_data; + if (!id->driver_data) { + button_info = soc_button_get_button_info(dev); + if (IS_ERR(button_info)) + return PTR_ERR(button_info); + } else { + button_info = (struct soc_button_info *)id->driver_data; + } if (gpiod_count(dev, NULL) <= 0) { dev_dbg(dev, "no GPIO attached, ignoring...\n"); @@ -195,6 +348,9 @@ static int soc_button_probe(struct platform_device *pdev) if (!priv->children[0] && !priv->children[1]) return -ENODEV; + if (!id->driver_data) + devm_kfree(dev, button_info); + return 0; } @@ -214,6 +370,7 @@ static struct soc_button_info soc_button_PNP0C40[] = { static const struct acpi_device_id soc_button_acpi_match[] = { { "PNP0C40", (unsigned long)soc_button_PNP0C40 }, + { "ACPI0011", 0 }, { } }; |