diff options
| -rw-r--r-- | drivers/gpu/drm/vc4/vc4_hdmi.c | 88 | ||||
| -rw-r--r-- | drivers/gpu/drm/vc4/vc4_hdmi.h | 10 |
2 files changed, 34 insertions, 64 deletions
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index d33059865994..308f7440eb6a 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -279,7 +279,16 @@ vc4_hdmi_connector_detect(struct drm_connector *connector, bool force) struct vc4_hdmi *vc4_hdmi = connector_to_vc4_hdmi(connector); bool connected = false; - mutex_lock(&vc4_hdmi->mutex); + /* + * NOTE: This function should really take vc4_hdmi->mutex, but + * doing so results in reentrancy issues since + * cec_s_phys_addr_from_edid might call .adap_enable, which + * leads to that funtion being called with our mutex held. + * + * Concurrency isn't an issue at the moment since we don't share + * any state with any of the other frameworks so we can ignore + * the lock for now. + */ WARN_ON(pm_runtime_resume_and_get(&vc4_hdmi->pdev->dev)); @@ -304,13 +313,11 @@ vc4_hdmi_connector_detect(struct drm_connector *connector, bool force) vc4_hdmi_enable_scrambling(&vc4_hdmi->encoder.base); pm_runtime_put(&vc4_hdmi->pdev->dev); - mutex_unlock(&vc4_hdmi->mutex); return connector_status_connected; } cec_phys_addr_invalidate(vc4_hdmi->cec_adap); pm_runtime_put(&vc4_hdmi->pdev->dev); - mutex_unlock(&vc4_hdmi->mutex); return connector_status_disconnected; } @@ -320,14 +327,21 @@ static int vc4_hdmi_connector_get_modes(struct drm_connector *connector) int ret = 0; struct edid *edid; - mutex_lock(&vc4_hdmi->mutex); + /* + * NOTE: This function should really take vc4_hdmi->mutex, but + * doing so results in reentrancy issues since + * cec_s_phys_addr_from_edid might call .adap_enable, which + * leads to that funtion being called with our mutex held. + * + * Concurrency isn't an issue at the moment since we don't share + * any state with any of the other frameworks so we can ignore + * the lock for now. + */ edid = drm_get_edid(connector, vc4_hdmi->ddc); cec_s_phys_addr_from_edid(vc4_hdmi->cec_adap, edid); - if (!edid) { - ret = -ENODEV; - goto out; - } + if (!edid) + return -ENODEV; drm_connector_update_edid_property(connector, edid); ret = drm_add_edid_modes(connector, edid); @@ -345,9 +359,6 @@ static int vc4_hdmi_connector_get_modes(struct drm_connector *connector) } } -out: - mutex_unlock(&vc4_hdmi->mutex); - return ret; } @@ -2666,17 +2677,6 @@ static int vc4_hdmi_cec_enable(struct cec_adapter *adap) int ret; int idx; - /* - * NOTE: This function should really take vc4_hdmi->mutex, but doing so - * results in a reentrancy since cec_s_phys_addr_from_edid() called in - * .detect or .get_modes might call .adap_enable, which leads to this - * function being called with that mutex held. - * - * Concurrency is not an issue for the moment since we don't share any - * state with KMS, so we can ignore the lock for now, but we need to - * keep it in mind if we were to change that assumption. - */ - if (!drm_dev_enter(drm, &idx)) /* * We can't return an error code, because the CEC @@ -2691,6 +2691,8 @@ static int vc4_hdmi_cec_enable(struct cec_adapter *adap) return ret; } + mutex_lock(&vc4_hdmi->mutex); + spin_lock_irqsave(&vc4_hdmi->hw_lock, flags); val = HDMI_READ(HDMI_CEC_CNTRL_5); @@ -2725,6 +2727,7 @@ static int vc4_hdmi_cec_enable(struct cec_adapter *adap) spin_unlock_irqrestore(&vc4_hdmi->hw_lock, flags); + mutex_unlock(&vc4_hdmi->mutex); drm_dev_exit(idx); return 0; @@ -2745,16 +2748,7 @@ static int vc4_hdmi_cec_disable(struct cec_adapter *adap) */ return 0; - /* - * NOTE: This function should really take vc4_hdmi->mutex, but doing so - * results in a reentrancy since cec_s_phys_addr_from_edid() called in - * .detect or .get_modes might call .adap_enable, which leads to this - * function being called with that mutex held. - * - * Concurrency is not an issue for the moment since we don't share any - * state with KMS, so we can ignore the lock for now, but we need to - * keep it in mind if we were to change that assumption. - */ + mutex_lock(&vc4_hdmi->mutex); spin_lock_irqsave(&vc4_hdmi->hw_lock, flags); @@ -2766,6 +2760,8 @@ static int vc4_hdmi_cec_disable(struct cec_adapter *adap) spin_unlock_irqrestore(&vc4_hdmi->hw_lock, flags); + mutex_unlock(&vc4_hdmi->mutex); + pm_runtime_put(&vc4_hdmi->pdev->dev); drm_dev_exit(idx); @@ -2788,17 +2784,6 @@ static int vc4_hdmi_cec_adap_log_addr(struct cec_adapter *adap, u8 log_addr) unsigned long flags; int idx; - /* - * NOTE: This function should really take vc4_hdmi->mutex, but doing so - * results in a reentrancy since cec_s_phys_addr_from_edid() called in - * .detect or .get_modes might call .adap_enable, which leads to this - * function being called with that mutex held. - * - * Concurrency is not an issue for the moment since we don't share any - * state with KMS, so we can ignore the lock for now, but we need to - * keep it in mind if we were to change that assumption. - */ - if (!drm_dev_enter(drm, &idx)) /* * We can't return an error code, because the CEC @@ -2807,11 +2792,13 @@ static int vc4_hdmi_cec_adap_log_addr(struct cec_adapter *adap, u8 log_addr) */ return 0; + mutex_lock(&vc4_hdmi->mutex); spin_lock_irqsave(&vc4_hdmi->hw_lock, flags); HDMI_WRITE(HDMI_CEC_CNTRL_1, (HDMI_READ(HDMI_CEC_CNTRL_1) & ~VC4_HDMI_CEC_ADDR_MASK) | (log_addr & 0xf) << VC4_HDMI_CEC_ADDR_SHIFT); spin_unlock_irqrestore(&vc4_hdmi->hw_lock, flags); + mutex_unlock(&vc4_hdmi->mutex); drm_dev_exit(idx); @@ -2828,17 +2815,6 @@ static int vc4_hdmi_cec_adap_transmit(struct cec_adapter *adap, u8 attempts, unsigned int i; int idx; - /* - * NOTE: This function should really take vc4_hdmi->mutex, but doing so - * results in a reentrancy since cec_s_phys_addr_from_edid() called in - * .detect or .get_modes might call .adap_enable, which leads to this - * function being called with that mutex held. - * - * Concurrency is not an issue for the moment since we don't share any - * state with KMS, so we can ignore the lock for now, but we need to - * keep it in mind if we were to change that assumption. - */ - if (!drm_dev_enter(dev, &idx)) return -ENODEV; @@ -2848,6 +2824,8 @@ static int vc4_hdmi_cec_adap_transmit(struct cec_adapter *adap, u8 attempts, return -ENOMEM; } + mutex_lock(&vc4_hdmi->mutex); + spin_lock_irqsave(&vc4_hdmi->hw_lock, flags); for (i = 0; i < msg->len; i += 4) @@ -2867,7 +2845,7 @@ static int vc4_hdmi_cec_adap_transmit(struct cec_adapter *adap, u8 attempts, HDMI_WRITE(HDMI_CEC_CNTRL_1, val); spin_unlock_irqrestore(&vc4_hdmi->hw_lock, flags); - + mutex_unlock(&vc4_hdmi->mutex); drm_dev_exit(idx); return 0; diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.h b/drivers/gpu/drm/vc4/vc4_hdmi.h index 79495ef79f09..db823efb2563 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.h +++ b/drivers/gpu/drm/vc4/vc4_hdmi.h @@ -195,15 +195,7 @@ struct vc4_hdmi { /** * @mutex: Mutex protecting the driver access across multiple - * frameworks (KMS, ALSA). - * - * NOTE: While supported, CEC has been left out since - * cec_s_phys_addr_from_edid() might call .adap_enable and lead to a - * reentrancy issue between .get_modes (or .detect) and .adap_enable. - * Since we don't share any state between the CEC hooks and KMS', it's - * not a big deal. The only trouble might come from updating the CEC - * clock divider which might be affected by a modeset, but CEC should - * be resilient to that. + * frameworks (KMS, ALSA, CEC). */ struct mutex mutex; |