diff options
| -rw-r--r-- | drivers/hid/hid-google-hammer.c | 413 |
1 files changed, 394 insertions, 19 deletions
diff --git a/drivers/hid/hid-google-hammer.c b/drivers/hid/hid-google-hammer.c index 6bf4da7ad63a..de3e7d055ca4 100644 --- a/drivers/hid/hid-google-hammer.c +++ b/drivers/hid/hid-google-hammer.c @@ -13,16 +13,268 @@ * any later version. */ +#include <linux/acpi.h> #include <linux/hid.h> #include <linux/leds.h> +#include <linux/mfd/cros_ec.h> +#include <linux/mfd/cros_ec_commands.h> #include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pm_wakeup.h> +#include <asm/unaligned.h> #include "hid-ids.h" -#define MAX_BRIGHTNESS 100 +/* + * C(hrome)B(ase)A(ttached)S(witch) - switch exported by Chrome EC and reporting + * state of the "Whiskers" base - attached or detached. Whiskers USB device also + * reports position of the keyboard - folded or not. Combining base state and + * position allows us to generate proper "Tablet mode" events. + */ +struct cbas_ec { + struct device *dev; /* The platform device (EC) */ + struct input_dev *input; + bool base_present; + struct notifier_block notifier; +}; -/* HID usage for keyboard backlight (Alphanumeric display brightness) */ -#define HID_AD_BRIGHTNESS 0x00140046 +static struct cbas_ec cbas_ec; +static DEFINE_SPINLOCK(cbas_ec_lock); +static DEFINE_MUTEX(cbas_ec_reglock); + +static bool cbas_parse_base_state(const void *data) +{ + u32 switches = get_unaligned_le32(data); + + return !!(switches & BIT(EC_MKBP_BASE_ATTACHED)); +} + +static int cbas_ec_query_base(struct cros_ec_device *ec_dev, bool get_state, + bool *state) +{ + struct ec_params_mkbp_info *params; + struct cros_ec_command *msg; + int ret; + + msg = kzalloc(sizeof(*msg) + max(sizeof(u32), sizeof(*params)), + GFP_KERNEL); + if (!msg) + return -ENOMEM; + + msg->command = EC_CMD_MKBP_INFO; + msg->version = 1; + msg->outsize = sizeof(*params); + msg->insize = sizeof(u32); + params = (struct ec_params_mkbp_info *)msg->data; + params->info_type = get_state ? + EC_MKBP_INFO_CURRENT : EC_MKBP_INFO_SUPPORTED; + params->event_type = EC_MKBP_EVENT_SWITCH; + + ret = cros_ec_cmd_xfer_status(ec_dev, msg); + if (ret >= 0) { + if (ret != sizeof(u32)) { + dev_warn(ec_dev->dev, "wrong result size: %d != %zu\n", + ret, sizeof(u32)); + ret = -EPROTO; + } else { + *state = cbas_parse_base_state(msg->data); + ret = 0; + } + } + + kfree(msg); + + return ret; +} + +static int cbas_ec_notify(struct notifier_block *nb, + unsigned long queued_during_suspend, + void *_notify) +{ + struct cros_ec_device *ec = _notify; + unsigned long flags; + bool base_present; + + if (ec->event_data.event_type == EC_MKBP_EVENT_SWITCH) { + base_present = cbas_parse_base_state( + &ec->event_data.data.switches); + dev_dbg(cbas_ec.dev, + "%s: base: %d\n", __func__, base_present); + + if (device_may_wakeup(cbas_ec.dev) || + !queued_during_suspend) { + + pm_wakeup_event(cbas_ec.dev, 0); + + spin_lock_irqsave(&cbas_ec_lock, flags); + + /* + * While input layer dedupes the events, we do not want + * to disrupt the state reported by the base by + * overriding it with state reported by the LID. Only + * report changes, as we assume that on attach the base + * is not folded. + */ + if (base_present != cbas_ec.base_present) { + input_report_switch(cbas_ec.input, + SW_TABLET_MODE, + !base_present); + input_sync(cbas_ec.input); + cbas_ec.base_present = base_present; + } + + spin_unlock_irqrestore(&cbas_ec_lock, flags); + } + } + + return NOTIFY_OK; +} + +static __maybe_unused int cbas_ec_resume(struct device *dev) +{ + struct cros_ec_device *ec = dev_get_drvdata(dev->parent); + bool base_present; + int error; + + error = cbas_ec_query_base(ec, true, &base_present); + if (error) { + dev_warn(dev, "failed to fetch base state on resume: %d\n", + error); + } else { + spin_lock_irq(&cbas_ec_lock); + + cbas_ec.base_present = base_present; + + /* + * Only report if base is disconnected. If base is connected, + * it will resend its state on resume, and we'll update it + * in hammer_event(). + */ + if (!cbas_ec.base_present) { + input_report_switch(cbas_ec.input, SW_TABLET_MODE, 1); + input_sync(cbas_ec.input); + } + + spin_unlock_irq(&cbas_ec_lock); + } + + return 0; +} + +static const SIMPLE_DEV_PM_OPS(cbas_ec_pm_ops, NULL, cbas_ec_resume); + +static void cbas_ec_set_input(struct input_dev *input) +{ + /* Take the lock so hammer_event() does not race with us here */ + spin_lock_irq(&cbas_ec_lock); + cbas_ec.input = input; + spin_unlock_irq(&cbas_ec_lock); +} + +static int __cbas_ec_probe(struct platform_device *pdev) +{ + struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent); + struct input_dev *input; + bool base_supported; + int error; + + error = cbas_ec_query_base(ec, false, &base_supported); + if (error) + return error; + + if (!base_supported) + return -ENXIO; + + input = devm_input_allocate_device(&pdev->dev); + if (!input) + return -ENOMEM; + + input->name = "Whiskers Tablet Mode Switch"; + input->id.bustype = BUS_HOST; + + input_set_capability(input, EV_SW, SW_TABLET_MODE); + + error = input_register_device(input); + if (error) { + dev_err(&pdev->dev, "cannot register input device: %d\n", + error); + return error; + } + + /* Seed the state */ + error = cbas_ec_query_base(ec, true, &cbas_ec.base_present); + if (error) { + dev_err(&pdev->dev, "cannot query base state: %d\n", error); + return error; + } + + input_report_switch(input, SW_TABLET_MODE, !cbas_ec.base_present); + + cbas_ec_set_input(input); + + cbas_ec.dev = &pdev->dev; + cbas_ec.notifier.notifier_call = cbas_ec_notify; + error = blocking_notifier_chain_register(&ec->event_notifier, + &cbas_ec.notifier); + if (error) { + dev_err(&pdev->dev, "cannot register notifier: %d\n", error); + cbas_ec_set_input(NULL); + return error; + } + + device_init_wakeup(&pdev->dev, true); + return 0; +} + +static int cbas_ec_probe(struct platform_device *pdev) +{ + int retval; + + mutex_lock(&cbas_ec_reglock); + + if (cbas_ec.input) { + retval = -EBUSY; + goto out; + } + + retval = __cbas_ec_probe(pdev); + +out: + mutex_unlock(&cbas_ec_reglock); + return retval; +} + +static int cbas_ec_remove(struct platform_device *pdev) +{ + struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent); + + mutex_lock(&cbas_ec_reglock); + + blocking_notifier_chain_unregister(&ec->event_notifier, + &cbas_ec.notifier); + cbas_ec_set_input(NULL); + + mutex_unlock(&cbas_ec_reglock); + return 0; +} + +static const struct acpi_device_id cbas_ec_acpi_ids[] = { + { "GOOG000B", 0 }, + { } +}; +MODULE_DEVICE_TABLE(acpi, cbas_ec_acpi_ids); + +static struct platform_driver cbas_ec_driver = { + .probe = cbas_ec_probe, + .remove = cbas_ec_remove, + .driver = { + .name = "cbas_ec", + .acpi_match_table = ACPI_PTR(cbas_ec_acpi_ids), + .pm = &cbas_ec_pm_ops, + }, +}; + +#define MAX_BRIGHTNESS 100 struct hammer_kbd_leds { struct led_classdev cdev; @@ -90,33 +342,130 @@ static int hammer_register_leds(struct hid_device *hdev) return devm_led_classdev_register(&hdev->dev, &kbd_backlight->cdev); } -static int hammer_input_configured(struct hid_device *hdev, - struct hid_input *hi) +#define HID_UP_GOOGLEVENDOR 0xffd10000 +#define HID_VD_KBD_FOLDED 0x00000019 +#define WHISKERS_KBD_FOLDED (HID_UP_GOOGLEVENDOR | HID_VD_KBD_FOLDED) + +/* HID usage for keyboard backlight (Alphanumeric display brightness) */ +#define HID_AD_BRIGHTNESS 0x00140046 + +static int hammer_input_mapping(struct hid_device *hdev, struct hid_input *hi, + struct hid_field *field, + struct hid_usage *usage, + unsigned long **bit, int *max) { - struct list_head *report_list = - &hdev->report_enum[HID_OUTPUT_REPORT].report_list; + if (hdev->product == USB_DEVICE_ID_GOOGLE_WHISKERS && + usage->hid == WHISKERS_KBD_FOLDED) { + /* + * We do not want to have this usage mapped as it will get + * mixed in with "base attached" signal and delivered over + * separate input device for tablet switch mode. + */ + return -1; + } + + return 0; +} + +static int hammer_event(struct hid_device *hid, struct hid_field *field, + struct hid_usage *usage, __s32 value) +{ + unsigned long flags; + + if (hid->product == USB_DEVICE_ID_GOOGLE_WHISKERS && + usage->hid == WHISKERS_KBD_FOLDED) { + spin_lock_irqsave(&cbas_ec_lock, flags); + + hid_dbg(hid, "%s: base: %d, folded: %d\n", __func__, + cbas_ec.base_present, value); + + /* + * We should not get event if base is detached, but in case + * we happen to service HID and EC notifications out of order + * let's still check the "base present" flag. + */ + if (cbas_ec.input && cbas_ec.base_present) { + input_report_switch(cbas_ec.input, + SW_TABLET_MODE, value); + input_sync(cbas_ec.input); + } + + spin_unlock_irqrestore(&cbas_ec_lock, flags); + return 1; /* We handled this event */ + } + + return 0; +} + +static bool hammer_is_keyboard_interface(struct hid_device *hdev) +{ + struct hid_report_enum *re = &hdev->report_enum[HID_INPUT_REPORT]; struct hid_report *report; - if (list_empty(report_list)) - return 0; + list_for_each_entry(report, &re->report_list, list) + if (report->application == HID_GD_KEYBOARD) + return true; - report = list_first_entry(report_list, struct hid_report, list); + return false; +} + +static bool hammer_has_backlight_control(struct hid_device *hdev) +{ + struct hid_report_enum *re = &hdev->report_enum[HID_OUTPUT_REPORT]; + struct hid_report *report; + int i, j; - if (report->maxfield == 1 && - report->field[0]->application == HID_GD_KEYBOARD && - report->field[0]->maxusage == 1 && - report->field[0]->usage[0].hid == HID_AD_BRIGHTNESS) { - int err = hammer_register_leds(hdev); + list_for_each_entry(report, &re->report_list, list) { + if (report->application != HID_GD_KEYBOARD) + continue; - if (err) + for (i = 0; i < report->maxfield; i++) { + struct hid_field *field = report->field[i]; + + for (j = 0; j < field->maxusage; j++) + if (field->usage[j].hid == HID_AD_BRIGHTNESS) + return true; + } + } + + return false; +} + +static int hammer_probe(struct hid_device *hdev, + const struct hid_device_id *id) +{ + int error; + + /* + * We always want to poll for, and handle tablet mode events from + * Whiskers, even when nobody has opened the input device. This also + * prevents the hid core from dropping early tablet mode events from + * the device. + */ + if (hdev->product == USB_DEVICE_ID_GOOGLE_WHISKERS && + hammer_is_keyboard_interface(hdev)) + hdev->quirks |= HID_QUIRK_ALWAYS_POLL; + + error = hid_parse(hdev); + if (error) + return error; + + error = hid_hw_start(hdev, HID_CONNECT_DEFAULT); + if (error) + return error; + + if (hammer_has_backlight_control(hdev)) { + error = hammer_register_leds(hdev); + if (error) hid_warn(hdev, "Failed to register keyboard backlight: %d\n", - err); + error); } return 0; } + static const struct hid_device_id hammer_devices[] = { { HID_DEVICE(BUS_USB, HID_GROUP_GENERIC, USB_VENDOR_ID_GOOGLE, USB_DEVICE_ID_GOOGLE_HAMMER) }, @@ -133,8 +482,34 @@ MODULE_DEVICE_TABLE(hid, hammer_devices); static struct hid_driver hammer_driver = { .name = "hammer", .id_table = hammer_devices, - .input_configured = hammer_input_configured, + .probe = hammer_probe, + .input_mapping = hammer_input_mapping, + .event = hammer_event, }; -module_hid_driver(hammer_driver); + +static int __init hammer_init(void) +{ + int error; + + error = platform_driver_register(&cbas_ec_driver); + if (error) + return error; + + error = hid_register_driver(&hammer_driver); + if (error) { + platform_driver_unregister(&cbas_ec_driver); + return error; + } + + return 0; +} +module_init(hammer_init); + +static void __exit hammer_exit(void) +{ + hid_unregister_driver(&hammer_driver); + platform_driver_unregister(&cbas_ec_driver); +} +module_exit(hammer_exit); MODULE_LICENSE("GPL"); |