diff options
Diffstat (limited to 'drivers/gpu/drm/display/drm_hdmi_cec_helper.c')
| -rw-r--r-- | drivers/gpu/drm/display/drm_hdmi_cec_helper.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/drivers/gpu/drm/display/drm_hdmi_cec_helper.c b/drivers/gpu/drm/display/drm_hdmi_cec_helper.c new file mode 100644 index 000000000000..3651ad0f76e0 --- /dev/null +++ b/drivers/gpu/drm/display/drm_hdmi_cec_helper.c @@ -0,0 +1,193 @@ +// SPDX-License-Identifier: MIT +/* + * Copyright (c) 2024 Linaro Ltd + */ + +#include <drm/drm_bridge.h> +#include <drm/drm_connector.h> +#include <drm/drm_managed.h> +#include <drm/display/drm_hdmi_cec_helper.h> + +#include <linux/export.h> +#include <linux/mutex.h> + +#include <media/cec.h> + +struct drm_connector_hdmi_cec_data { + struct cec_adapter *adapter; + const struct drm_connector_hdmi_cec_funcs *funcs; +}; + +static int drm_connector_hdmi_cec_adap_enable(struct cec_adapter *adap, bool enable) +{ + struct drm_connector *connector = cec_get_drvdata(adap); + struct drm_connector_hdmi_cec_data *data = connector->cec.data; + + return data->funcs->enable(connector, enable); +} + +static int drm_connector_hdmi_cec_adap_log_addr(struct cec_adapter *adap, u8 logical_addr) +{ + struct drm_connector *connector = cec_get_drvdata(adap); + struct drm_connector_hdmi_cec_data *data = connector->cec.data; + + return data->funcs->log_addr(connector, logical_addr); +} + +static int drm_connector_hdmi_cec_adap_transmit(struct cec_adapter *adap, u8 attempts, + u32 signal_free_time, struct cec_msg *msg) +{ + struct drm_connector *connector = cec_get_drvdata(adap); + struct drm_connector_hdmi_cec_data *data = connector->cec.data; + + return data->funcs->transmit(connector, attempts, signal_free_time, msg); +} + +static const struct cec_adap_ops drm_connector_hdmi_cec_adap_ops = { + .adap_enable = drm_connector_hdmi_cec_adap_enable, + .adap_log_addr = drm_connector_hdmi_cec_adap_log_addr, + .adap_transmit = drm_connector_hdmi_cec_adap_transmit, +}; + +static void drm_connector_hdmi_cec_adapter_phys_addr_invalidate(struct drm_connector *connector) +{ + struct drm_connector_hdmi_cec_data *data = connector->cec.data; + + cec_phys_addr_invalidate(data->adapter); +} + +static void drm_connector_hdmi_cec_adapter_phys_addr_set(struct drm_connector *connector, + u16 addr) +{ + struct drm_connector_hdmi_cec_data *data = connector->cec.data; + + cec_s_phys_addr(data->adapter, addr, false); +} + +static void drm_connector_hdmi_cec_adapter_unregister(struct drm_device *dev, void *res) +{ + struct drm_connector *connector = res; + struct drm_connector_hdmi_cec_data *data = connector->cec.data; + + cec_unregister_adapter(data->adapter); + + if (data->funcs->uninit) + data->funcs->uninit(connector); + + kfree(data); + connector->cec.data = NULL; +} + +static struct drm_connector_cec_funcs drm_connector_hdmi_cec_adapter_funcs = { + .phys_addr_invalidate = drm_connector_hdmi_cec_adapter_phys_addr_invalidate, + .phys_addr_set = drm_connector_hdmi_cec_adapter_phys_addr_set, +}; + +int drmm_connector_hdmi_cec_register(struct drm_connector *connector, + const struct drm_connector_hdmi_cec_funcs *funcs, + const char *name, + u8 available_las, + struct device *dev) +{ + struct drm_connector_hdmi_cec_data *data; + struct cec_connector_info conn_info; + struct cec_adapter *cec_adap; + int ret; + + if (!funcs->init || !funcs->enable || !funcs->log_addr || !funcs->transmit) + return -EINVAL; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->funcs = funcs; + + cec_adap = cec_allocate_adapter(&drm_connector_hdmi_cec_adap_ops, connector, name, + CEC_CAP_DEFAULTS | CEC_CAP_CONNECTOR_INFO, + available_las ? : CEC_MAX_LOG_ADDRS); + ret = PTR_ERR_OR_ZERO(cec_adap); + if (ret < 0) + goto err_free; + + cec_fill_conn_info_from_drm(&conn_info, connector); + cec_s_conn_info(cec_adap, &conn_info); + + data->adapter = cec_adap; + + mutex_lock(&connector->cec.mutex); + + connector->cec.data = data; + connector->cec.funcs = &drm_connector_hdmi_cec_adapter_funcs; + + ret = funcs->init(connector); + if (ret < 0) + goto err_delete_adapter; + + /* + * NOTE: the CEC adapter will be unregistered by drmm cleanup from + * drm_managed_release(), which is called from drm_dev_release() + * during device unbind. + * + * However, the CEC framework cleans up the CEC adapter only when the + * last user has closed its file descriptor, so we don't need to handle + * it in DRM. + * + * Before that CEC framework makes sure that even if the userspace + * still holds CEC device open, all calls will be shortcut via + * cec_is_registered(), making sure that there is no access to the + * freed memory. + */ + ret = cec_register_adapter(cec_adap, dev); + if (ret < 0) + goto err_delete_adapter; + + mutex_unlock(&connector->cec.mutex); + + return drmm_add_action_or_reset(connector->dev, + drm_connector_hdmi_cec_adapter_unregister, + connector); + +err_delete_adapter: + cec_delete_adapter(cec_adap); + + connector->cec.data = NULL; + + mutex_unlock(&connector->cec.mutex); + +err_free: + kfree(data); + + return ret; +} +EXPORT_SYMBOL(drmm_connector_hdmi_cec_register); + +void drm_connector_hdmi_cec_received_msg(struct drm_connector *connector, + struct cec_msg *msg) +{ + struct drm_connector_hdmi_cec_data *data = connector->cec.data; + + cec_received_msg(data->adapter, msg); +} +EXPORT_SYMBOL(drm_connector_hdmi_cec_received_msg); + +void drm_connector_hdmi_cec_transmit_attempt_done(struct drm_connector *connector, + u8 status) +{ + struct drm_connector_hdmi_cec_data *data = connector->cec.data; + + cec_transmit_attempt_done(data->adapter, status); +} +EXPORT_SYMBOL(drm_connector_hdmi_cec_transmit_attempt_done); + +void drm_connector_hdmi_cec_transmit_done(struct drm_connector *connector, + u8 status, + u8 arb_lost_cnt, u8 nack_cnt, + u8 low_drive_cnt, u8 error_cnt) +{ + struct drm_connector_hdmi_cec_data *data = connector->cec.data; + + cec_transmit_done(data->adapter, status, + arb_lost_cnt, nack_cnt, low_drive_cnt, error_cnt); +} +EXPORT_SYMBOL(drm_connector_hdmi_cec_transmit_done); |