On 02/07/18 16:55, Ville Syrjälä wrote: > On Thu, Jun 28, 2018 at 09:42:51AM +0200, Hans Verkuil wrote: >> From: Hans Verkuil <hans.verkuil@xxxxxxxxx> >> >> This adds support for the DisplayPort CEC-Tunneling-over-AUX >> feature that is part of the DisplayPort 1.3 standard. >> >> Unfortunately, not all DisplayPort/USB-C to HDMI adapters with a >> chip that has this capability actually hook up the CEC pin, so >> even though a CEC device is created, it may not actually work. >> >> Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx> >> --- >> drivers/gpu/drm/Kconfig | 10 + >> drivers/gpu/drm/Makefile | 1 + >> drivers/gpu/drm/drm_dp_cec.c | 433 ++++++++++++++++++++++++++++++++ >> drivers/gpu/drm/drm_dp_helper.c | 1 + >> include/drm/drm_dp_helper.h | 56 +++++ >> 5 files changed, 501 insertions(+) >> create mode 100644 drivers/gpu/drm/drm_dp_cec.c >> >> diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig >> index 2a72d2feb76d..d5e217fd0c14 100644 >> --- a/drivers/gpu/drm/Kconfig >> +++ b/drivers/gpu/drm/Kconfig >> @@ -122,6 +122,16 @@ config DRM_LOAD_EDID_FIRMWARE >> default case is N. Details and instructions how to build your own >> EDID data are given in Documentation/EDID/HOWTO.txt. >> >> +config DRM_DP_CEC >> + bool "Enable DisplayPort CEC-Tunneling-over-AUX HDMI support" >> + select CEC_CORE >> + help >> + Choose this option if you want to enable HDMI CEC support for >> + DisplayPort/USB-C to HDMI adapters. >> + >> + Note: not all adapters support this feature, and even for those >> + that do support this they often do not hook up the CEC pin. >> + >> config DRM_TTM >> tristate >> depends on DRM && MMU >> diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile >> index ef9f3dab287f..270266cc6eca 100644 >> --- a/drivers/gpu/drm/Makefile >> +++ b/drivers/gpu/drm/Makefile >> @@ -41,6 +41,7 @@ drm_kms_helper-$(CONFIG_DRM_PANEL_BRIDGE) += bridge/panel.o >> drm_kms_helper-$(CONFIG_DRM_FBDEV_EMULATION) += drm_fb_helper.o >> drm_kms_helper-$(CONFIG_DRM_KMS_CMA_HELPER) += drm_fb_cma_helper.o >> drm_kms_helper-$(CONFIG_DRM_DP_AUX_CHARDEV) += drm_dp_aux_dev.o >> +drm_kms_helper-$(CONFIG_DRM_DP_CEC) += drm_dp_cec.o >> >> obj-$(CONFIG_DRM_KMS_HELPER) += drm_kms_helper.o >> obj-$(CONFIG_DRM_DEBUG_SELFTEST) += selftests/ >> diff --git a/drivers/gpu/drm/drm_dp_cec.c b/drivers/gpu/drm/drm_dp_cec.c >> new file mode 100644 >> index 000000000000..1530ca685955 >> --- /dev/null >> +++ b/drivers/gpu/drm/drm_dp_cec.c >> @@ -0,0 +1,433 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* >> + * DisplayPort CEC-Tunneling-over-AUX support >> + * >> + * Copyright 2018 Cisco Systems, Inc. and/or its affiliates. All rights reserved. >> + */ >> + >> +#include <linux/kernel.h> >> +#include <linux/module.h> >> +#include <linux/slab.h> >> +#include <drm/drm_dp_helper.h> >> +#include <media/cec.h> >> + >> +/* >> + * Unfortunately it turns out that we have a chicken-and-egg situation >> + * here. Quite a few active (mini-)DP-to-HDMI or USB-C-to-HDMI adapters >> + * have a converter chip that supports CEC-Tunneling-over-AUX (usually the >> + * Parade PS176), but they do not wire up the CEC pin, thus making CEC >> + * useless. >> + * >> + * Sadly there is no way for this driver to know this. What happens is >> + * that a /dev/cecX device is created that is isolated and unable to see >> + * any of the other CEC devices. Quite literally the CEC wire is cut >> + * (or in this case, never connected in the first place). >> + * >> + * The reason so few adapters support this is that this tunneling protocol >> + * was never supported by any OS. So there was no easy way of testing it, >> + * and no incentive to correctly wire up the CEC pin. >> + * >> + * Hopefully by creating this driver it will be easier for vendors to >> + * finally fix their adapters and test the CEC functionality. >> + * >> + * I keep a list of known working adapters here: >> + * >> + * https://hverkuil.home.xs4all.nl/cec-status.txt >> + * >> + * Please mail me (hverkuil@xxxxxxxxx) if you find an adapter that works >> + * and is not yet listed there. >> + * >> + * Note that the current implementation does not support CEC over an MST hub. >> + * As far as I can see there is no mechanism defined in the DisplayPort >> + * standard to transport CEC interrupts over an MST device. It might be >> + * possible to do this through polling, but I have not been able to get that >> + * to work. >> + */ >> + >> +/** >> + * DOC: dp cec helpers >> + * >> + * These functions take care of supporting the CEC-Tunneling-over-AUX >> + * feature of DisplayPort-to-HDMI adapters. >> + */ >> + >> +/* >> + * When the EDID is unset because the HPD went low, then the CEC DPCD registers >> + * typically can no longer be read (true for a DP-to-HDMI adapter since it is >> + * powered by the HPD). However, some displays toggle the HPD off and on for a >> + * short period for one reason or another, and that would cause the CEC adapter >> + * to be removed and added again, even though nothing else changed. >> + * >> + * This module parameter sets a delay in seconds before the CEC adapter is >> + * actually unregistered. Only if the HPD does not return within that time will >> + * the CEC adapter be unregistered. >> + * >> + * If it is set to a value >= NEVER_UNREG_DELAY, then the CEC adapter will never >> + * be unregistered for as long as the connector remains registered. >> + * >> + * If it is set to 0, then the CEC adapter will be unregistered immediately as >> + * soon as the HPD disappears. >> + * >> + * The default is one second to prevent short HPD glitches from unregistering >> + * the CEC adapter. >> + * >> + * Note that for integrated HDMI branch devices that support CEC the DPCD >> + * registers remain available even if the HPD goes low since it is not powered >> + * by the HPD. In that case the CEC adapter will never be unregistered during >> + * the life time of the connector. At least, this is the theory since I do not >> + * have hardware with an integrated HDMI branch device that supports CEC. >> + */ >> +#define NEVER_UNREG_DELAY 1000 >> +static unsigned int drm_dp_cec_unregister_delay = 1; >> +module_param(drm_dp_cec_unregister_delay, uint, 0600); >> +MODULE_PARM_DESC(drm_dp_cec_unregister_delay, >> + "CEC unregister delay in seconds, 0: no delay, >= 1000: never unregister"); >> + >> +static int drm_dp_cec_adap_enable(struct cec_adapter *adap, bool enable) >> +{ >> + struct drm_dp_aux *aux = cec_get_drvdata(adap); >> + u32 val = enable ? DP_CEC_TUNNELING_ENABLE : 0; >> + ssize_t err = 0; >> + >> + err = drm_dp_dpcd_writeb(aux, DP_CEC_TUNNELING_CONTROL, val); >> + return (enable && err < 0) ? err : 0; >> +} >> + >> +static int drm_dp_cec_adap_log_addr(struct cec_adapter *adap, u8 addr) >> +{ >> + struct drm_dp_aux *aux = cec_get_drvdata(adap); >> + /* Bit 15 (logical address 15) should always be set */ >> + u16 la_mask = 1 << CEC_LOG_ADDR_BROADCAST; >> + u8 mask[2]; >> + ssize_t err; >> + >> + if (addr != CEC_LOG_ADDR_INVALID) >> + la_mask |= adap->log_addrs.log_addr_mask | (1 << addr); >> + mask[0] = la_mask & 0xff; >> + mask[1] = la_mask >> 8; >> + err = drm_dp_dpcd_write(aux, DP_CEC_LOGICAL_ADDRESS_MASK, mask, 2); >> + return (addr != CEC_LOG_ADDR_INVALID && err < 0) ? err : 0; >> +} >> + >> +static int drm_dp_cec_adap_transmit(struct cec_adapter *adap, u8 attempts, >> + u32 signal_free_time, struct cec_msg *msg) >> +{ >> + struct drm_dp_aux *aux = cec_get_drvdata(adap); >> + unsigned int retries = min(5, attempts - 1); >> + ssize_t err; >> + >> + err = drm_dp_dpcd_write(aux, DP_CEC_TX_MESSAGE_BUFFER, >> + msg->msg, msg->len); >> + if (err < 0) >> + return err; >> + >> + err = drm_dp_dpcd_writeb(aux, DP_CEC_TX_MESSAGE_INFO, >> + (msg->len - 1) | (retries << 4) | >> + DP_CEC_TX_MESSAGE_SEND); >> + return err < 0 ? err : 0; >> +} >> + >> +static int drm_dp_cec_adap_monitor_all_enable(struct cec_adapter *adap, >> + bool enable) >> +{ >> + struct drm_dp_aux *aux = cec_get_drvdata(adap); >> + ssize_t err; >> + u8 val; >> + >> + if (!(adap->capabilities & CEC_CAP_MONITOR_ALL)) >> + return 0; >> + >> + err = drm_dp_dpcd_readb(aux, DP_CEC_TUNNELING_CONTROL, &val); >> + if (err >= 0) { >> + if (enable) >> + val |= DP_CEC_SNOOPING_ENABLE; >> + else >> + val &= ~DP_CEC_SNOOPING_ENABLE; >> + err = drm_dp_dpcd_writeb(aux, DP_CEC_TUNNELING_CONTROL, val); >> + } >> + return (enable && err < 0) ? err : 0; >> +} >> + >> +static void drm_dp_cec_adap_status(struct cec_adapter *adap, >> + struct seq_file *file) >> +{ >> + struct drm_dp_aux *aux = cec_get_drvdata(adap); >> + struct drm_dp_desc desc; >> + struct drm_dp_dpcd_ident *id = &desc.ident; >> + >> + if (drm_dp_read_desc(aux, &desc, true)) >> + return; >> + seq_printf(file, "OUI: %*pdH\n", >> + (int)sizeof(id->oui), id->oui); >> + seq_printf(file, "ID: %*pE\n", >> + (int)strnlen(id->device_id, sizeof(id->device_id)), >> + id->device_id); >> + seq_printf(file, "HW Rev: %d.%d\n", id->hw_rev >> 4, id->hw_rev & 0xf); >> + /* >> + * Show this both in decimal and hex: at least one vendor >> + * always reports this in hex. >> + */ >> + seq_printf(file, "FW/SW Rev: %d.%d (0x%02x.0x%02x)\n", >> + id->sw_major_rev, id->sw_minor_rev, >> + id->sw_major_rev, id->sw_minor_rev); >> +} >> + >> +static const struct cec_adap_ops drm_dp_cec_adap_ops = { >> + .adap_enable = drm_dp_cec_adap_enable, >> + .adap_log_addr = drm_dp_cec_adap_log_addr, >> + .adap_transmit = drm_dp_cec_adap_transmit, >> + .adap_monitor_all_enable = drm_dp_cec_adap_monitor_all_enable, >> + .adap_status = drm_dp_cec_adap_status, >> +}; >> + >> +static int drm_dp_cec_received(struct drm_dp_aux *aux) >> +{ >> + struct cec_adapter *adap = aux->cec.adap; >> + struct cec_msg msg; >> + u8 rx_msg_info; >> + ssize_t err; >> + >> + err = drm_dp_dpcd_readb(aux, DP_CEC_RX_MESSAGE_INFO, &rx_msg_info); >> + if (err < 0) >> + return err; >> + >> + if (!(rx_msg_info & DP_CEC_RX_MESSAGE_ENDED)) >> + return 0; >> + >> + msg.len = (rx_msg_info & DP_CEC_RX_MESSAGE_LEN_MASK) + 1; >> + err = drm_dp_dpcd_read(aux, DP_CEC_RX_MESSAGE_BUFFER, msg.msg, msg.len); >> + if (err < 0) >> + return err; >> + >> + cec_received_msg(adap, &msg); >> + return 0; >> +} >> + >> +static void drm_dp_cec_handle_irq(struct drm_dp_aux *aux) >> +{ >> + struct cec_adapter *adap = aux->cec.adap; >> + u8 flags; >> + >> + if (drm_dp_dpcd_readb(aux, DP_CEC_TUNNELING_IRQ_FLAGS, &flags) < 0) >> + return; >> + >> + if (flags & DP_CEC_RX_MESSAGE_INFO_VALID) >> + drm_dp_cec_received(aux); >> + >> + if (flags & DP_CEC_TX_MESSAGE_SENT) >> + cec_transmit_attempt_done(adap, CEC_TX_STATUS_OK); >> + else if (flags & DP_CEC_TX_LINE_ERROR) >> + cec_transmit_attempt_done(adap, CEC_TX_STATUS_ERROR | >> + CEC_TX_STATUS_MAX_RETRIES); >> + else if (flags & >> + (DP_CEC_TX_ADDRESS_NACK_ERROR | DP_CEC_TX_DATA_NACK_ERROR)) >> + cec_transmit_attempt_done(adap, CEC_TX_STATUS_NACK | >> + CEC_TX_STATUS_MAX_RETRIES); >> + drm_dp_dpcd_writeb(aux, DP_CEC_TUNNELING_IRQ_FLAGS, flags); >> +} >> + >> +/** >> + * drm_dp_cec_irq() - handle CEC interrupt, if any >> + * @aux: DisplayPort AUX channel >> + * >> + * Should be called when handling an IRQ_HPD request. If CEC-tunneling-over-AUX >> + * is present, then it will check for a CEC_IRQ and handle it accordingly. >> + */ >> +void drm_dp_cec_irq(struct drm_dp_aux *aux) >> +{ >> + u8 cec_irq; >> + int ret; >> + >> + mutex_lock(&aux->cec.lock); >> + if (!aux->cec.adap) >> + goto unlock; >> + >> + ret = drm_dp_dpcd_readb(aux, DP_DEVICE_SERVICE_IRQ_VECTOR_ESI1, >> + &cec_irq); >> + if (ret < 0 || !(cec_irq & DP_CEC_IRQ)) >> + goto unlock; >> + >> + drm_dp_cec_handle_irq(aux); >> + drm_dp_dpcd_writeb(aux, DP_DEVICE_SERVICE_IRQ_VECTOR_ESI1, DP_CEC_IRQ); >> +unlock: >> + mutex_unlock(&aux->cec.lock); >> +} >> +EXPORT_SYMBOL(drm_dp_cec_irq); >> + >> +static bool drm_dp_cec_cap(struct drm_dp_aux *aux, u8 *cec_cap) >> +{ >> + u8 cap = 0; >> + >> + if (drm_dp_dpcd_readb(aux, DP_CEC_TUNNELING_CAPABILITY, &cap) != 1 || >> + !(cap & DP_CEC_TUNNELING_CAPABLE)) >> + return false; >> + if (cec_cap) >> + *cec_cap = cap; >> + return true; >> +} >> + >> +/* >> + * Called if the HPD was low for more than drm_dp_cec_unregister_delay >> + * seconds. This unregisters the CEC adapter. >> + */ >> +static void drm_dp_cec_unregister_work(struct work_struct *work) >> +{ >> + struct drm_dp_aux *aux = container_of(work, struct drm_dp_aux, >> + cec.unregister_work.work); >> + >> + if (!aux->cec.adap) >> + return; > > I guess this NULL check isn't particularly critical? Correct. It can be removed since cec_unregister_adapter() also checks against NULL. > >> + mutex_lock(&aux->cec.lock); >> + cec_unregister_adapter(aux->cec.adap); >> + aux->cec.adap = NULL; >> + mutex_unlock(&aux->cec.lock); >> +} >> + >> +/* >> + * A new EDID is set. If there is no CEC adapter, then create one. If >> + * there was a CEC adapter, then check if the CEC adapter properties >> + * were unchanged and just update the CEC physical address. Otherwise >> + * unregister the old CEC adapter and create a new one. >> + */ >> +void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid) >> +{ >> + u32 cec_caps = CEC_CAP_DEFAULTS | CEC_CAP_NEEDS_HPD; >> + unsigned int num_las = 1; >> + u8 cap; >> + >> +#ifndef CONFIG_MEDIA_CEC_RC >> + /* >> + * CEC_CAP_RC is part of CEC_CAP_DEFAULTS, but it is stripped by >> + * cec_allocate_adapter() if CONFIG_MEDIA_CEC_RC is undefined. >> + * >> + * Do this here as well to ensure the tests against cec_caps are >> + * correct. >> + */ >> + cec_caps &= ~CEC_CAP_RC; >> +#endif >> + cancel_delayed_work_sync(&aux->cec.unregister_work); >> + >> + mutex_lock(&aux->cec.lock); >> + if (!drm_dp_cec_cap(aux, &cap)) { >> + /* CEC is not supported, unregister any existing adapter */ >> + cec_unregister_adapter(aux->cec.adap); > > ... considering here we don't check for NULL. > > Also the check in the work is unlocked so I could imagine some slight > race conditions if set_edid()/unset_edid() get called in a particularly > funky way. But I suppose we shouldn't really do that so it's probably > fine. And the cec_unregister_adapter() is done with the lock held anyway > so any bogus pointers can't reach it. Right. > >> + aux->cec.adap = NULL; >> + goto unlock; >> + } >> + >> + if (cap & DP_CEC_SNOOPING_CAPABLE) >> + cec_caps |= CEC_CAP_MONITOR_ALL; >> + if (cap & DP_CEC_MULTIPLE_LA_CAPABLE) >> + num_las = CEC_MAX_LOG_ADDRS; >> + >> + if (aux->cec.adap) { >> + if (aux->cec.adap->capabilities == cec_caps && >> + aux->cec.adap->available_log_addrs == num_las) { >> + /* Unchanged, so just set the phys addr */ >> + cec_s_phys_addr_from_edid(aux->cec.adap, edid); >> + goto unlock; >> + } >> + /* >> + * The capabilities changed, so unregister the old >> + * adapter first. >> + */ >> + cec_unregister_adapter(aux->cec.adap); >> + } >> + >> + /* Create a new adapter */ >> + aux->cec.adap = cec_allocate_adapter(&drm_dp_cec_adap_ops, >> + aux, aux->cec.name, cec_caps, >> + num_las); >> + if (IS_ERR(aux->cec.adap)) { >> + aux->cec.adap = NULL; >> + goto unlock; >> + } >> + if (cec_register_adapter(aux->cec.adap, aux->cec.parent)) { >> + cec_delete_adapter(aux->cec.adap); >> + aux->cec.adap = NULL; >> + } else { >> + /* >> + * Update the phys addr for the new CEC adapter. When called >> + * from drm_dp_cec_register_connector() edid == NULL, so in >> + * that case the phys addr is just invalidated. >> + */ >> + cec_s_phys_addr_from_edid(aux->cec.adap, edid); >> + } >> +unlock: >> + mutex_unlock(&aux->cec.lock); >> +} >> +EXPORT_SYMBOL(drm_dp_cec_set_edid); >> + >> +/* >> + * The EDID disappeared (likely because of the HPD going down). >> + */ >> +void drm_dp_cec_unset_edid(struct drm_dp_aux *aux) >> +{ >> + mutex_lock(&aux->cec.lock); >> + if (!aux->cec.adap) >> + goto unlock; >> + cec_phys_addr_invalidate(aux->cec.adap); >> + /* >> + * We're done if we want to keep the CEC device >> + * (drm_dp_cec_unregister_delay is >= NEVER_UNREG_DELAY) or if the >> + * DPCD still indicates the CEC capability (expected for an integrated >> + * HDMI branch device). >> + */ >> + if (drm_dp_cec_unregister_delay >= NEVER_UNREG_DELAY || >> + drm_dp_cec_cap(aux, NULL)) >> + goto unlock; >> + >> + mutex_unlock(&aux->cec.lock); >> + cancel_delayed_work_sync(&aux->cec.unregister_work); >> + mutex_lock(&aux->cec.lock); > > Can't we just do the cancel_work_sync() at the very start of the > function? Good point. That allows me to simplify this code a bit as well. > > Either way this shouldn't deadlock anymore. For the series > Reviewed-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> I'll post a v8, making these changes and adding your Reviewed-by. Thanks for your review! Hans > >> + >> + if (aux->cec.adap) { >> + /* >> + * Unregister the CEC adapter after drm_dp_cec_unregister_delay >> + * seconds. This to debounce short HPD off-and-on cycles from >> + * displays. >> + */ >> + schedule_delayed_work(&aux->cec.unregister_work, >> + drm_dp_cec_unregister_delay * HZ); >> + } >> +unlock: >> + mutex_unlock(&aux->cec.lock); >> +} >> +EXPORT_SYMBOL(drm_dp_cec_unset_edid); >> + >> +/** >> + * drm_dp_cec_register_connector() - register a new connector >> + * @aux: DisplayPort AUX channel >> + * @name: name of the CEC device >> + * @parent: parent device >> + * >> + * A new connector was registered with associated CEC adapter name and >> + * CEC adapter parent device. After registering the name and parent >> + * drm_dp_cec_set_edid() is called to check if the connector supports >> + * CEC and to register a CEC adapter if that is the case. >> + */ >> +void drm_dp_cec_register_connector(struct drm_dp_aux *aux, const char *name, >> + struct device *parent) >> +{ >> + WARN_ON(aux->cec.adap); >> + aux->cec.name = name; >> + aux->cec.parent = parent; >> + INIT_DELAYED_WORK(&aux->cec.unregister_work, drm_dp_cec_unregister_work); >> + >> + drm_dp_cec_set_edid(aux, NULL); >> +} >> +EXPORT_SYMBOL(drm_dp_cec_register_connector); >> + >> +/** >> + * drm_dp_cec_unregister_connector() - unregister the CEC adapter, if any >> + * @aux: DisplayPort AUX channel >> + */ >> +void drm_dp_cec_unregister_connector(struct drm_dp_aux *aux) >> +{ >> + if (!aux->cec.adap) >> + return; >> + cancel_delayed_work_sync(&aux->cec.unregister_work); >> + cec_unregister_adapter(aux->cec.adap); >> + aux->cec.adap = NULL; >> +} >> +EXPORT_SYMBOL(drm_dp_cec_unregister_connector); >> diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c >> index a7ba602a43a8..f4a06b54aa7d 100644 >> --- a/drivers/gpu/drm/drm_dp_helper.c >> +++ b/drivers/gpu/drm/drm_dp_helper.c >> @@ -1087,6 +1087,7 @@ static void drm_dp_aux_crc_work(struct work_struct *work) >> void drm_dp_aux_init(struct drm_dp_aux *aux) >> { >> mutex_init(&aux->hw_mutex); >> + mutex_init(&aux->cec.lock); >> INIT_WORK(&aux->crc_work, drm_dp_aux_crc_work); >> >> aux->ddc.algo = &drm_dp_i2c_algo; >> diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h >> index c01564991a9f..d0a23db271dc 100644 >> --- a/include/drm/drm_dp_helper.h >> +++ b/include/drm/drm_dp_helper.h >> @@ -1078,6 +1078,25 @@ struct drm_dp_aux_msg { >> size_t size; >> }; >> >> +struct cec_adapter; >> +struct edid; >> + >> +/** >> + * struct drm_dp_aux_cec - DisplayPort CEC-Tunneling-over-AUX >> + * @lock: mutex protecting this struct >> + * @adap: the CEC adapter for CEC-Tunneling-over-AUX support. >> + * @name: name of the CEC adapter >> + * @parent: parent device of the CEC adapter >> + * @unregister_work: unregister the CEC adapter >> + */ >> +struct drm_dp_aux_cec { >> + struct mutex lock; >> + struct cec_adapter *adap; >> + const char *name; >> + struct device *parent; >> + struct delayed_work unregister_work; >> +}; >> + >> /** >> * struct drm_dp_aux - DisplayPort AUX channel >> * @name: user-visible name of this AUX channel and the I2C-over-AUX adapter >> @@ -1136,6 +1155,10 @@ struct drm_dp_aux { >> * @i2c_defer_count: Counts I2C DEFERs, used for DP validation. >> */ >> unsigned i2c_defer_count; >> + /** >> + * @cec: struct containing fields used for CEC-Tunneling-over-AUX. >> + */ >> + struct drm_dp_aux_cec cec; >> }; >> >> ssize_t drm_dp_dpcd_read(struct drm_dp_aux *aux, unsigned int offset, >> @@ -1258,4 +1281,37 @@ drm_dp_has_quirk(const struct drm_dp_desc *desc, enum drm_dp_quirk quirk) >> return desc->quirks & BIT(quirk); >> } >> >> +#ifdef CONFIG_DRM_DP_CEC >> +void drm_dp_cec_irq(struct drm_dp_aux *aux); >> +void drm_dp_cec_register_connector(struct drm_dp_aux *aux, const char *name, >> + struct device *parent); >> +void drm_dp_cec_unregister_connector(struct drm_dp_aux *aux); >> +void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid); >> +void drm_dp_cec_unset_edid(struct drm_dp_aux *aux); >> +#else >> +static inline void drm_dp_cec_irq(struct drm_dp_aux *aux) >> +{ >> +} >> + >> +static inline void drm_dp_cec_register_connector(struct drm_dp_aux *aux, >> + const char *name, >> + struct device *parent) >> +{ >> +} >> + >> +static inline void drm_dp_cec_unregister_connector(struct drm_dp_aux *aux) >> +{ >> +} >> + >> +static inline void drm_dp_cec_set_edid(struct drm_dp_aux *aux, >> + const struct edid *edid) >> +{ >> +} >> + >> +static inline void drm_dp_cec_unset_edid(struct drm_dp_aux *aux) >> +{ >> +} >> + >> +#endif >> + >> #endif /* _DRM_DP_HELPER_H_ */ >> -- >> 2.17.0 > _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
