From 627563d1696b8978b550ed192acc1bc8fc461da5 Mon Sep 17 00:00:00 2001 From: Russell King Date: Sat, 28 Mar 2015 18:13:52 +0000 Subject: drm/edid: add function to help find SADs Add a function to find the start of the SADs in the ELD. This complements the helper to retrieve the SAD count. Signed-off-by: Russell King --- include/drm/drm_edid.h | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'include/drm') diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h index 799050198323..53c53c459b15 100644 --- a/include/drm/drm_edid.h +++ b/include/drm/drm_edid.h @@ -347,6 +347,25 @@ static inline int drm_eld_mnl(const uint8_t *eld) return (eld[DRM_ELD_CEA_EDID_VER_MNL] & DRM_ELD_MNL_MASK) >> DRM_ELD_MNL_SHIFT; } +/** + * drm_eld_sad - Get ELD SAD structures. + * @eld: pointer to an eld memory structure with sad_count set + */ +static inline const uint8_t *drm_eld_sad(const uint8_t *eld) +{ + unsigned int ver, mnl; + + ver = (eld[DRM_ELD_VER] & DRM_ELD_VER_MASK) >> DRM_ELD_VER_SHIFT; + if (ver != 2 && ver != 31) + return NULL; + + mnl = drm_eld_mnl(eld); + if (mnl > 16) + return NULL; + + return eld + DRM_ELD_CEA_SAD(mnl, 0); +} + /** * drm_eld_sad_count - Get ELD SAD count. * @eld: pointer to an eld memory structure with sad_count set -- cgit v1.2.3 From b5814fff27c6d0212b86306bdd01fe3aea99cabb Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 27 Mar 2015 12:50:58 +0000 Subject: drm: bridge/dw_hdmi: introduce interface to setting sample rate Introduce dw_hdmi_set_sample_rate(), which allows us to configure the audio sample rate, setting the CTS/N values appropriately. Tested-by: Yakir Yang Signed-off-by: Russell King --- drivers/gpu/drm/bridge/dw_hdmi.c | 10 ++++++++++ include/drm/bridge/dw_hdmi.h | 5 +++++ 2 files changed, 15 insertions(+) (limited to 'include/drm') diff --git a/drivers/gpu/drm/bridge/dw_hdmi.c b/drivers/gpu/drm/bridge/dw_hdmi.c index eeb01693812a..0ed8c49f1c6e 100644 --- a/drivers/gpu/drm/bridge/dw_hdmi.c +++ b/drivers/gpu/drm/bridge/dw_hdmi.c @@ -365,6 +365,16 @@ static void hdmi_clk_regenerator_update_pixel_clock(struct dw_hdmi *hdmi) mutex_unlock(&hdmi->audio_mutex); } +void dw_hdmi_set_sample_rate(struct dw_hdmi *hdmi, unsigned int rate) +{ + mutex_lock(&hdmi->audio_mutex); + hdmi->sample_rate = rate; + hdmi_set_clk_regenerator(hdmi, hdmi->hdmi_data.video_mode.mpixelclock, + hdmi->sample_rate, hdmi->ratio); + mutex_unlock(&hdmi->audio_mutex); +} +EXPORT_SYMBOL_GPL(dw_hdmi_set_sample_rate); + /* * this submodule is responsible for the video data synchronization. * for example, for RGB 4:4:4 input, the data map is defined as diff --git a/include/drm/bridge/dw_hdmi.h b/include/drm/bridge/dw_hdmi.h index de13bfc35634..763af51e1d60 100644 --- a/include/drm/bridge/dw_hdmi.h +++ b/include/drm/bridge/dw_hdmi.h @@ -12,6 +12,8 @@ #include +struct dw_hdmi; + enum { DW_HDMI_RES_8, DW_HDMI_RES_10, @@ -59,4 +61,7 @@ int dw_hdmi_bind(struct device *dev, struct device *master, void *data, struct drm_encoder *encoder, struct resource *iores, int irq, const struct dw_hdmi_plat_data *plat_data); + +void dw_hdmi_set_sample_rate(struct dw_hdmi *hdmi, unsigned int rate); + #endif /* __IMX_HDMI_H__ */ -- cgit v1.2.3 From b90120a9660884b8f11bbb9904fbaa4c12d17e0a Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 27 Mar 2015 12:59:58 +0000 Subject: drm: bridge/dw_hdmi: introduce interfaces to enable and disable audio iMX6 devices suffer from an errata (ERR005174) where the audio FIFO can be emptied while it is partially full, resulting in misalignment of the audio samples. To prevent this, the errata workaround recommends writing N as zero until the audio FIFO has been loaded by DMA. Writing N=0 prevents the HDMI bridge from reading from the audio FIFO, effectively disabling audio. This means we need to provide the audio driver with a pair of functions to enable/disable audio. These are dw_hdmi_audio_enable() and dw_hdmi_audio_disable(). A spinlock is introduced to ensure that setting the CTS/N values can't race, ensuring that the audio driver calling the enable/disable functions (which are called in an atomic context) can't race with a modeset. Tested-by: Yakir Yang Signed-off-by: Russell King --- drivers/gpu/drm/bridge/dw_hdmi.c | 34 +++++++++++++++++++++++++++++++++- include/drm/bridge/dw_hdmi.h | 2 ++ 2 files changed, 35 insertions(+), 1 deletion(-) (limited to 'include/drm') diff --git a/drivers/gpu/drm/bridge/dw_hdmi.c b/drivers/gpu/drm/bridge/dw_hdmi.c index 0ed8c49f1c6e..f070ee07b8c9 100644 --- a/drivers/gpu/drm/bridge/dw_hdmi.c +++ b/drivers/gpu/drm/bridge/dw_hdmi.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include @@ -123,8 +124,12 @@ struct dw_hdmi { struct i2c_adapter *ddc; void __iomem *regs; + spinlock_t audio_lock; struct mutex audio_mutex; unsigned int sample_rate; + unsigned int audio_cts; + unsigned int audio_n; + bool audio_enable; int ratio; void (*write)(struct dw_hdmi *hdmi, u8 val, int offset); @@ -346,7 +351,11 @@ static void hdmi_set_clk_regenerator(struct dw_hdmi *hdmi, dev_dbg(hdmi->dev, "%s: samplerate=%ukHz ratio=%d pixelclk=%luMHz N=%d cts=%d\n", __func__, sample_rate, ratio, pixel_clk, n, cts); - hdmi_set_cts_n(hdmi, cts, n); + spin_lock_irq(&hdmi->audio_lock); + hdmi->audio_n = n; + hdmi->audio_cts = cts; + hdmi_set_cts_n(hdmi, cts, hdmi->audio_enable ? n : 0); + spin_unlock_irq(&hdmi->audio_lock); } static void hdmi_init_clk_regenerator(struct dw_hdmi *hdmi) @@ -375,6 +384,28 @@ void dw_hdmi_set_sample_rate(struct dw_hdmi *hdmi, unsigned int rate) } EXPORT_SYMBOL_GPL(dw_hdmi_set_sample_rate); +void dw_hdmi_audio_enable(struct dw_hdmi *hdmi) +{ + unsigned long flags; + + spin_lock_irqsave(&hdmi->audio_lock, flags); + hdmi->audio_enable = true; + hdmi_set_cts_n(hdmi, hdmi->audio_cts, hdmi->audio_n); + spin_unlock_irqrestore(&hdmi->audio_lock, flags); +} +EXPORT_SYMBOL_GPL(dw_hdmi_audio_enable); + +void dw_hdmi_audio_disable(struct dw_hdmi *hdmi) +{ + unsigned long flags; + + spin_lock_irqsave(&hdmi->audio_lock, flags); + hdmi->audio_enable = false; + hdmi_set_cts_n(hdmi, hdmi->audio_cts, 0); + spin_unlock_irqrestore(&hdmi->audio_lock, flags); +} +EXPORT_SYMBOL_GPL(dw_hdmi_audio_disable); + /* * this submodule is responsible for the video data synchronization. * for example, for RGB 4:4:4 input, the data map is defined as @@ -1577,6 +1608,7 @@ int dw_hdmi_bind(struct device *dev, struct device *master, hdmi->encoder = encoder; mutex_init(&hdmi->audio_mutex); + spin_lock_init(&hdmi->audio_lock); of_property_read_u32(np, "reg-io-width", &val); diff --git a/include/drm/bridge/dw_hdmi.h b/include/drm/bridge/dw_hdmi.h index 763af51e1d60..bae79f3c4d28 100644 --- a/include/drm/bridge/dw_hdmi.h +++ b/include/drm/bridge/dw_hdmi.h @@ -63,5 +63,7 @@ int dw_hdmi_bind(struct device *dev, struct device *master, const struct dw_hdmi_plat_data *plat_data); void dw_hdmi_set_sample_rate(struct dw_hdmi *hdmi, unsigned int rate); +void dw_hdmi_audio_enable(struct dw_hdmi *hdmi); +void dw_hdmi_audio_disable(struct dw_hdmi *hdmi); #endif /* __IMX_HDMI_H__ */ -- cgit v1.2.3