// SPDX-License-Identifier: GPL-2.0+ // Driver to instantiate Chromebook i2c/smbus devices. // // Copyright (C) 2012 Google, Inc. // Author: Benson Leung #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include #include #define ATMEL_TP_I2C_ADDR 0x4b #define ATMEL_TP_I2C_BL_ADDR 0x25 #define ATMEL_TS_I2C_ADDR 0x4a #define ATMEL_TS_I2C_BL_ADDR 0x26 #define CYAPA_TP_I2C_ADDR 0x67 #define ELAN_TP_I2C_ADDR 0x15 #define ISL_ALS_I2C_ADDR 0x44 #define TAOS_ALS_I2C_ADDR 0x29 static const char *i2c_adapter_names[] = { "SMBus I801 adapter", "i915 gmbus vga", "i915 gmbus panel", "Synopsys DesignWare I2C adapter", }; /* Keep this enum consistent with i2c_adapter_names */ enum i2c_adapter_type { I2C_ADAPTER_SMBUS = 0, I2C_ADAPTER_VGADDC, I2C_ADAPTER_PANEL, I2C_ADAPTER_DESIGNWARE, }; struct i2c_peripheral { struct i2c_board_info board_info; unsigned short alt_addr; const char *dmi_name; unsigned long irqflags; struct resource irq_resource; enum i2c_adapter_type type; u32 pci_devid; struct i2c_client *client; }; struct acpi_peripheral { char hid[ACPI_ID_LEN]; const struct property_entry *properties; }; struct chromeos_laptop { /* * Note that we can't mark this pointer as const because * i2c_new_probed_device() changes passed in I2C board info, so. */ struct i2c_peripheral *i2c_peripherals; unsigned int num_i2c_peripherals; const struct acpi_peripheral *acpi_peripherals; unsigned int num_acpi_peripherals; }; static const struct chromeos_laptop *cros_laptop; static struct i2c_client * chromes_laptop_instantiate_i2c_device(struct i2c_adapter *adapter, struct i2c_board_info *info, unsigned short alt_addr) { const unsigned short addr_list[] = { info->addr, I2C_CLIENT_END }; struct i2c_client *client; /* * Add the i2c device. If we can't detect it at the primary * address we scan secondary addresses. In any case the client * structure gets assigned primary address. */ client = i2c_new_probed_device(adapter, info, addr_list, NULL); if (!client && alt_addr) { struct i2c_board_info dummy_info = { I2C_BOARD_INFO("dummy", info->addr), }; const unsigned short alt_addr_list[] = { alt_addr, I2C_CLIENT_END }; struct i2c_client *dummy; dummy = i2c_new_probed_device(adapter, &dummy_info, alt_addr_list, NULL); if (dummy) { pr_debug("%d-%02x is probed at %02x\n", adapter->nr, info->addr, dummy->addr); i2c_unregister_device(dummy); client = i2c_new_device(adapter, info); } } if (!client) pr_debug("failed to register device %d-%02x\n", adapter->nr, info->addr); else pr_debug("added i2c device %d-%02x\n", adapter->nr, info->addr); return client; } static bool chromeos_laptop_match_adapter_devid(struct device *dev, u32 devid) { struct pci_dev *pdev; if (!dev_is_pci(dev)) return false; pdev = to_pci_dev(dev); return devid == PCI_DEVID(pdev->bus->number, pdev->devfn); } static void chromeos_laptop_check_adapter(struct i2c_adapter *adapter) { struct i2c_peripheral *i2c_dev; int i; for (i = 0; i < cros_laptop->num_i2c_peripherals; i++) { i2c_dev = &cros_laptop->i2c_peripherals[i]; /* Skip devices already created */ if (i2c_dev->client) continue; if (strncmp(adapter->name, i2c_adapter_names[i2c_dev->type], strlen(i2c_adapter_names[i2c_dev->type]))) continue; if (i2c_dev->pci_devid && !chromeos_laptop_match_adapter_devid(adapter->dev.parent, i2c_dev->pci_devid)) { continue; } i2c_dev->client = chromes_laptop_instantiate_i2c_device(adapter, &i2c_dev->board_info, i2c_dev->alt_addr); } } static bool chromeos_laptop_adjust_client(struct i2c_client *client) { const struct acpi_peripheral *acpi_dev; struct acpi_device_id acpi_ids[2] = { }; int i; int error; if (!has_acpi_companion(&client->dev)) return false; for (i = 0; i < cros_laptop->num_acpi_peripherals; i++) { acpi_dev = &cros_laptop->acpi_peripherals[i]; memcpy(acpi_ids[0].id, acpi_dev->hid, ACPI_ID_LEN); if (acpi_match_device(acpi_ids, &client->dev)) { error = device_add_properties(&client->dev, acpi_dev->properties); if (error) { dev_err(&client->dev, "failed to add properties: %d\n", error); break; } return true; } } return false; } static void chromeos_laptop_detach_i2c_client(struct i2c_client *client) { struct i2c_peripheral *i2c_dev; int i; for (i = 0; i < cros_laptop->num_i2c_peripherals; i++) { i2c_dev = &cros_laptop->i2c_peripherals[i]; if (i2c_dev->client == client) i2c_dev->client = NULL; } } static int chromeos_laptop_i2c_notifier_call(struct notifier_block *nb, unsigned long action, void *data) { struct device *dev = data; switch (action) { case BUS_NOTIFY_ADD_DEVICE: if (dev->type == &i2c_adapter_type) chromeos_laptop_check_adapter(to_i2c_adapter(dev)); else if (dev->type == &i2c_client_type) chromeos_laptop_adjust_client(to_i2c_client(dev)); break; case BUS_NOTIFY_REMOVED_DEVICE: if (dev->type == &i2c_client_type) chromeos_laptop_detach_i2c_client(to_i2c_client(dev)); break; } return 0; } static struct notifier_block chromeos_laptop_i2c_notifier = { .notifier_call = chromeos_laptop_i2c_notifier_call, }; #define DECLARE_CROS_LAPTOP(_name) \ static const struct chromeos_laptop _name __initconst = { \ .i2c_peripherals = _name##_peripherals, \ .num_i2c_peripherals = ARRAY_SIZE(_name##_peripherals), \ } #define DECLARE_ACPI_CROS_LAPTOP(_name) \ static const struct chromeos_laptop _name __initconst = { \ .acpi_peripherals = _name##_peripherals, \ .num_acpi_peripherals = ARRAY_SIZE(_name##_peripherals), \ } static struct i2c_peripheral samsung_series_5_550_peripherals[] __initdata = { /* Touchpad. */ { .board_info = { I2C_BOARD_INFO("cyapa", CYAPA_TP_I2C_ADDR), .flags = I2C_CLIENT_WAKE, }, .dmi_name = "trackpad", .type = I2C_ADAPTER_SMBUS, }, /* Light Sensor. */ { .board_info = { I2C_BOARD_INFO("isl29018", ISL_ALS_I2C_ADDR), }, .dmi_name = "lightsensor", .type = I2C_ADAPTER_SMBUS, }, }; DECLARE_CROS_LAPTOP(samsung_series_5_550); static struct i2c_peripheral samsung_series_5_peripherals[] __initdata = { /* Light Sensor. */ { .board_info = { I2C_BOARD_INFO("tsl2583", TAOS_ALS_I2C_ADDR), }, .type = I2C_ADAPTER_SMBUS, }, }; DECLARE_CROS_LAPTOP(samsung_series_5); static const int chromebook_pixel_tp_keys[] __initconst = { KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, BTN_LEFT }; static const struct property_entry chromebook_pixel_trackpad_props[] __initconst = { PROPERTY_ENTRY_STRING("compatible", "atmel,maxtouch"), PROPERTY_ENTRY_U32_ARRAY("linux,gpio-keymap", chromebook_pixel_tp_keys), { } }; static const struct property_entry chromebook_atmel_touchscreen_props[] __initconst = { PROPERTY_ENTRY_STRING("compatible", "atmel,maxtouch"), { } }; static struct i2c_peripheral chromebook_pixel_peripherals[] __initdata = { /* Touch Screen. */ { .board_info = { I2C_BOARD_INFO("atmel_mxt_ts", ATMEL_TS_I2C_ADDR), .properties = chromebook_atmel_touchscreen_props, .flags = I2C_CLIENT_WAKE, }, .dmi_name = "touchscreen", .irqflags = IRQF_TRIGGER_FALLING, .type = I2C_ADAPTER_PANEL, .alt_addr = ATMEL_TS_I2C_BL_ADDR, }, /* Touchpad. */ { .board_info = { I2C_BOARD_INFO("atmel_mxt_tp", ATMEL_TP_I2C_ADDR), .properties = chromebook_pixel_trackpad_props, .flags = I2C_CLIENT_WAKE, }, .dmi_name = "trackpad", .irqflags = IRQF_TRIGGER_FALLING, .type = I2C_ADAPTER_VGADDC, .alt_addr = ATMEL_TP_I2C_BL_ADDR, }, /* Light Sensor. */ { .board_info = { I2C_BOARD_INFO("isl29018", ISL_ALS_I2C_ADDR), }, .dmi_name = "lightsensor", .type = I2C_ADAPTER_PANEL, }, }; DECLARE_CROS_LAPTOP(chromebook_pixel); static struct i2c_peripheral hp_chromebook_14_peripherals[] __initdata = { /* Touchpad. */ { .board_info = { I2C_BOARD_INFO("cyapa", CYAPA_TP_I2C_ADDR), .flags = I2C_CLIENT_WAKE, }, .dmi_name = "trackpad", .type = I2C_ADAPTER_DESIGNWARE, }, }; DECLARE_CROS_LAPTOP(hp_chromebook_14); static struct i2c_peripheral dell_chromebook_11_peripherals[] __initdata = { /* Touchpad. */ { .board_info = { I2C_BOARD_INFO("cyapa", CYAPA_TP_I2C_ADDR), .flags = I2C_CLIENT_WAKE, }, .dmi_name = "trackpad", .type = I2C_ADAPTER_DESIGNWARE, }, /* Elan Touchpad option. */ { .board_info = { I2C_BOARD_INFO("elan_i2c", ELAN_TP_I2C_ADDR), .flags = I2C_CLIENT_WAKE, }, .dmi_name = "trackpad", .type = I2C_ADAPTER_DESIGNWARE, }, }; DECLARE_CROS_LAPTOP(dell_chromebook_11); static struct i2c_peripheral toshiba_cb35_peripherals[] __initdata = { /* Touchpad. */ { .board_info = { I2C_BOARD_INFO("cyapa", CYAPA_TP_I2C_ADDR), .flags = I2C_CLIENT_WAKE, }, .dmi_name = "trackpad", .type = I2C_ADAPTER_DESIGNWARE, }, }; DECLARE_CROS_LAPTOP(toshiba_cb35); static struct i2c_peripheral acer_c7_chromebook_peripherals[] __initdata = { /* Touchpad. */ { .board_info = { I2C_BOARD_INFO("cyapa", CYAPA_TP_I2C_ADDR), .flags = I2C_CLIENT_WAKE, }, .dmi_name = "trackpad", .type = I2C_ADAPTER_SMBUS, }, }; DECLARE_CROS_LAPTOP(acer_c7_chromebook); static struct i2c_peripheral acer_ac700_peripherals[] __initdata = { /* Light Sensor. */ { .board_info = { I2C_BOARD_INFO("tsl2583", TAOS_ALS_I2C_ADDR), }, .type = I2C_ADAPTER_SMBUS, }, }; DECLARE_CROS_LAPTOP(acer_ac700); static struct i2c_peripheral acer_c720_peripherals[] __initdata = { /* Touchscreen. */ { .board_info = { I2C_BOARD_INFO("atmel_mxt_ts", ATMEL_TS_I2C_ADDR), .properties = chromebook_atmel_touchscreen_props, .flags = I2C_CLIENT_WAKE, }, .dmi_name = "touchscreen", .irqflags = IRQF_TRIGGER_FALLING, .type = I2C_ADAPTER_DESIGNWARE, .pci_devid = PCI_DEVID(0, PCI_DEVFN(0x15, 0x2)), .alt_addr = ATMEL_TS_I2C_BL_ADDR, }, /* Touchpad. */ { .board_info = { I2C_BOARD_INFO("cyapa", CYAPA_TP_I2C_ADDR), .flags = I2C_CLIENT_WAKE, }, .dmi_name = "trackpad", .type = I2C_ADAPTER_DESIGNWARE, .pci_devid = PCI_DEVID(0, PCI_DEVFN(0x15, 0x1)), }, /* Elan Touchpad option. */ { .board_info = { I2C_BOARD_INFO("elan_i2c", ELAN_TP_I2C_ADDR), .flags = I2C_CLIENT_WAKE, }, .dmi_name = "trackpad", .type = I2C_ADAPTER_DESIGNWARE, .pci_devid = PCI_DEVID(0, PCI_DEVFN(0x15, 0x1)), }, /* Light Sensor. */ { .board_info = { I2C_BOARD_INFO("isl29018", ISL_ALS_I2C_ADDR), }, .dmi_name = "lightsensor", .type = I2C_ADAPTER_DESIGNWARE, .pci_devid = PCI_DEVID(0, PCI_DEVFN(0x15, 0x2)), }, }; DECLARE_CROS_LAPTOP(acer_c720); static struct i2c_peripheral hp_pavilion_14_chromebook_peripherals[] __initdata = { /* Touchpad. */ { .board_info = { I2C_BOARD_INFO("cyapa", CYAPA_TP_I2C_ADDR), .flags = I2C_CLIENT_WAKE, }, .dmi_name = "trackpad", .type = I2C_ADAPTER_SMBUS, }, }; DECLARE_CROS_LAPTOP(hp_pavilion_14_chromebook); static struct i2c_peripheral cr48_peripherals[] __initdata = { /* Light Sensor. */ { .board_info = { I2C_BOARD_INFO("tsl2563", TAOS_ALS_I2C_ADDR), }, .type = I2C_ADAPTER_SMBUS, }, }; DECLARE_CROS_LAPTOP(cr48); static const u32 samus_touchpad_buttons[] __initconst = { KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, BTN_LEFT }; static const struct property_entry samus_trackpad_props[] __initconst = { PROPERTY_ENTRY_STRING("compatible", "atmel,maxtouch"), PROPERTY_ENTRY_U32_ARRAY("linux,gpio-keymap", samus_touchpad_buttons), { } }; static struct acpi_peripheral samus_peripherals[] __initdata = { /* Touchpad */ { .hid = "ATML0000", .properties = samus_trackpad_props, }, /* Touchsceen */ { .hid = "ATML0001", .properties = chromebook_atmel_touchscreen_props, }, }; DECLARE_ACPI_CROS_LAPTOP(samus); static struct acpi_peripheral generic_atmel_peripherals[] __initdata = { /* Touchpad */ { .hid = "ATML0000", .properties = chromebook_pixel_trackpad_props, }, /* Touchsceen */ { .hid = "ATML0001", .properties = chromebook_atmel_touchscreen_props, }, }; DECLARE_ACPI_CROS_LAPTOP(generic_atmel); static const struct dmi_system_id chromeos_laptop_dmi_table[] __initconst = { { .ident = "Samsung Series 5 550", .matches = { DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG"), DMI_MATCH(DMI_PRODUCT_NAME, "Lumpy"), }, .driver_data = (void *)&samsung_series_5_550, }, { .ident = "Samsung Series 5", .matches = { DMI_MATCH(DMI_PRODUCT_NAME, "Alex"), }, .driver_data = (void *)&samsung_series_5, }, { .ident = "Chromebook Pixel", .matches = { DMI_MATCH(DMI_SYS_VENDOR, "GOOGLE"), DMI_MATCH(DMI_PRODUCT_NAME, "Link"), }, .driver_data = (void *)&chromebook_pixel, }, { .ident = "Wolf", .matches = { DMI_MATCH(DMI_BIOS_VENDOR, "coreboot"), DMI_MATCH(DMI_PRODUCT_NAME, "Wolf"), }, .driver_data = (void *)&dell_chromebook_11, }, { .ident = "HP Chromebook 14", .matches = { DMI_MATCH(DMI_BIOS_VENDOR, "coreboot"), DMI_MATCH(DMI_PRODUCT_NAME, "Falco"), }, .driver_data = (void *)&hp_chromebook_14, }, { .ident = "Toshiba CB35", .matches = { DMI_MATCH(DMI_BIOS_VENDOR, "coreboot"), DMI_MATCH(DMI_PRODUCT_NAME, "Leon"), }, .driver_data = (void *)&toshiba_cb35, }, { .ident = "Acer C7 Chromebook", .matches = { DMI_MATCH(DMI_PRODUCT_NAME, "Parrot"), }, .driver_data = (void *)&acer_c7_chromebook, }, { .ident = "Acer AC700", .matches = { DMI_MATCH(DMI_PRODUCT_NAME, "ZGB"), }, .driver_data = (void *)&acer_ac700, }, { .ident = "Acer C720", .matches = { DMI_MATCH(DMI_PRODUCT_NAME, "Peppy"), }, .driver_data = (void *)&acer_c720, }, { .ident = "HP Pavilion 14 Chromebook", .matches = { DMI_MATCH(DMI_PRODUCT_NAME, "Butterfly"), }, .driver_data = (void *)&hp_pavilion_14_chromebook, }, { .ident = "Cr-48", .matches = { DMI_MATCH(DMI_PRODUCT_NAME, "Mario"), }, .driver_data = (void *)&cr48, }, /* Devices with peripherals incompletely described in ACPI */ { .ident = "Chromebook Pro", .matches = { DMI_MATCH(DMI_SYS_VENDOR, "Google"), DMI_MATCH(DMI_PRODUCT_NAME, "Caroline"), }, .driver_data = (void *)&samus, }, { .ident = "Google Pixel 2 (2015)", .matches = { DMI_MATCH(DMI_SYS_VENDOR, "GOOGLE"), DMI_MATCH(DMI_PRODUCT_NAME, "Samus"), }, .driver_data = (void *)&samus, }, { .ident = "Samsung Chromebook 3", .matches = { DMI_MATCH(DMI_SYS_VENDOR, "GOOGLE"), DMI_MATCH(DMI_PRODUCT_NAME, "Celes"), }, .driver_data = (void *)&samus, }, { /* * Other Chromebooks with Atmel touch controllers: * - Winky (touchpad) * - Clapper, Expresso, Rambi, Glimmer (touchscreen) */ .ident = "Other Chromebook", .matches = { /* * This will match all Google devices, not only devices * with Atmel, but we will validate that the device * actually has matching peripherals. */ DMI_MATCH(DMI_SYS_VENDOR, "GOOGLE"), }, .driver_data = (void *)&generic_atmel, }, { } }; MODULE_DEVICE_TABLE(dmi, chromeos_laptop_dmi_table); static int __init chromeos_laptop_scan_peripherals(struct device *dev, void *data) { int error; if (dev->type == &i2c_adapter_type) { chromeos_laptop_check_adapter(to_i2c_adapter(dev)); } else if (dev->type == &i2c_client_type) { if (chromeos_laptop_adjust_client(to_i2c_client(dev))) { /* * Now that we have needed properties re-trigger * driver probe in case driver was initialized * earlier and probe failed. */ error = device_attach(dev); if (error < 0) dev_warn(dev, "%s: device_attach() failed: %d\n", __func__, error); } } return 0; } static int __init chromeos_laptop_get_irq_from_dmi(const char *dmi_name) { const struct dmi_device *dmi_dev; const struct dmi_dev_onboard *dev_data; dmi_dev = dmi_find_device(DMI_DEV_TYPE_DEV_ONBOARD, dmi_name, NULL); if (!dmi_dev) { pr_err("failed to find DMI device '%s'\n", dmi_name); return -ENOENT; } dev_data = dmi_dev->device_data; if (!dev_data) { pr_err("failed to get data from DMI for '%s'\n", dmi_name); return -EINVAL; } return dev_data->instance; } static int __init chromeos_laptop_setup_irq(struct i2c_peripheral *i2c_dev) { int irq; if (i2c_dev->dmi_name) { irq = chromeos_laptop_get_irq_from_dmi(i2c_dev->dmi_name); if (irq < 0) return irq; i2c_dev->irq_resource = (struct resource) DEFINE_RES_NAMED(irq, 1, NULL, IORESOURCE_IRQ | i2c_dev->irqflags); i2c_dev->board_info.resources = &i2c_dev->irq_resource; i2c_dev->board_info.num_resources = 1; } return 0; } static int __init chromeos_laptop_prepare_i2c_peripherals(struct chromeos_laptop *cros_laptop, const struct chromeos_laptop *src) { struct i2c_peripheral *i2c_dev; struct i2c_board_info *info; int i; int error; if (!src->num_i2c_peripherals) return 0; cros_laptop->i2c_peripherals = kmemdup(src->i2c_peripherals, src->num_i2c_peripherals * sizeof(*src->i2c_peripherals), GFP_KERNEL); if (!cros_laptop->i2c_peripherals) return -ENOMEM; cros_laptop->num_i2c_peripherals = src->num_i2c_peripherals; for (i = 0; i < cros_laptop->num_i2c_peripherals; i++) { i2c_dev = &cros_laptop->i2c_peripherals[i]; info = &i2c_dev->board_info; error = chromeos_laptop_setup_irq(i2c_dev); if (error) goto err_out; /* We need to deep-copy properties */ if (info->properties) { info->properties = property_entries_dup(info->properties); if (IS_ERR(info->properties)) { error = PTR_ERR(info->properties); goto err_out; } } } return 0; err_out: while (--i >= 0) { i2c_dev = &cros_laptop->i2c_peripherals[i]; info = &i2c_dev->board_info; if (info->properties) property_entries_free(info->properties); } kfree(cros_laptop->i2c_peripherals); return error; } static int __init chromeos_laptop_prepare_acpi_peripherals(struct chromeos_laptop *cros_laptop, const struct chromeos_laptop *src) { struct acpi_peripheral *acpi_peripherals; struct acpi_peripheral *acpi_dev; const struct acpi_peripheral *src_dev; int n_peripherals = 0; int i; int error; for (i = 0; i < src->num_acpi_peripherals; i++) { if (acpi_dev_present(src->acpi_peripherals[i].hid, NULL, -1)) n_peripherals++; } if (!n_peripherals) return 0; acpi_peripherals = kcalloc(n_peripherals, sizeof(*src->acpi_peripherals), GFP_KERNEL); if (!acpi_peripherals) return -ENOMEM; acpi_dev = acpi_peripherals; for (i = 0; i < src->num_acpi_peripherals; i++) { src_dev = &src->acpi_peripherals[i]; if (!acpi_dev_present(src_dev->hid, NULL, -1)) continue; *acpi_dev = *src_dev; /* We need to deep-copy properties */ if (src_dev->properties) { acpi_dev->properties = property_entries_dup(src_dev->properties); if (IS_ERR(acpi_dev->properties)) { error = PTR_ERR(acpi_dev->properties); goto err_out; } } acpi_dev++; } cros_laptop->acpi_peripherals = acpi_peripherals; cros_laptop->num_acpi_peripherals = n_peripherals; return 0; err_out: while (--i >= 0) { acpi_dev = &acpi_peripherals[i]; if (acpi_dev->properties) property_entries_free(acpi_dev->properties); } kfree(acpi_peripherals); return error; } static void chromeos_laptop_destroy(const struct chromeos_laptop *cros_laptop) { const struct acpi_peripheral *acpi_dev; struct i2c_peripheral *i2c_dev; struct i2c_board_info *info; int i; for (i = 0; i < cros_laptop->num_i2c_peripherals; i++) { i2c_dev = &cros_laptop->i2c_peripherals[i]; info = &i2c_dev->board_info; if (i2c_dev->client) i2c_unregister_device(i2c_dev->client); if (info->properties) property_entries_free(info->properties); } for (i = 0; i < cros_laptop->num_acpi_peripherals; i++) { acpi_dev = &cros_laptop->acpi_peripherals[i]; if (acpi_dev->properties) property_entries_free(acpi_dev->properties); } kfree(cros_laptop->i2c_peripherals); kfree(cros_laptop->acpi_peripherals); kfree(cros_laptop); } static struct chromeos_laptop * __init chromeos_laptop_prepare(const struct chromeos_laptop *src) { struct chromeos_laptop *cros_laptop; int error; cros_laptop = kzalloc(sizeof(*cros_laptop), GFP_KERNEL); if (!cros_laptop) return ERR_PTR(-ENOMEM); error = chromeos_laptop_prepare_i2c_peripherals(cros_laptop, src); if (!error) error = chromeos_laptop_prepare_acpi_peripherals(cros_laptop, src); if (error) { chromeos_laptop_destroy(cros_laptop); return ERR_PTR(error); } return cros_laptop; } static int __init chromeos_laptop_init(void) { const struct dmi_system_id *dmi_id; int error; dmi_id = dmi_first_match(chromeos_laptop_dmi_table); if (!dmi_id) { pr_debug("unsupported system\n"); return -ENODEV; } pr_debug("DMI Matched %s\n", dmi_id->ident); cros_laptop = chromeos_laptop_prepare((void *)dmi_id->driver_data); if (IS_ERR(cros_laptop)) return PTR_ERR(cros_laptop); if (!cros_laptop->num_i2c_peripherals && !cros_laptop->num_acpi_peripherals) { pr_debug("no relevant devices detected\n"); error = -ENODEV; goto err_destroy_cros_laptop; } error = bus_register_notifier(&i2c_bus_type, &chromeos_laptop_i2c_notifier); if (error) { pr_err("failed to register i2c bus notifier: %d\n", error); goto err_destroy_cros_laptop; } /* * Scan adapters that have been registered and clients that have * been created before we installed the notifier to make sure * we do not miss any devices. */ i2c_for_each_dev(NULL, chromeos_laptop_scan_peripherals); return 0; err_destroy_cros_laptop: chromeos_laptop_destroy(cros_laptop); return error; } static void __exit chromeos_laptop_exit(void) { bus_unregister_notifier(&i2c_bus_type, &chromeos_laptop_i2c_notifier); chromeos_laptop_destroy(cros_laptop); } module_init(chromeos_laptop_init); module_exit(chromeos_laptop_exit); MODULE_DESCRIPTION("Chrome OS Laptop driver"); MODULE_AUTHOR("Benson Leung "); MODULE_LICENSE("GPL");