diff mbox series

[v1,3/6] drm/edid: Add cea_sad helpers for freq/length

Message ID 20210906193529.718845-4-msp@baylibre.com (mailing list archive)
State New, archived
Headers show
Series drm/mediatek: Add mt8195 DisplayPort driver | expand

Commit Message

Markus Schneider-Pargmann Sept. 6, 2021, 7:35 p.m. UTC 
This patch adds two helper functions that extract the frequency and word
length from a struct cea_sad.

For these helper functions new defines are added that help translate the
'freq' and 'byte2' fields into real numbers.

Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
---
 drivers/gpu/drm/drm_edid.c | 57 ++++++++++++++++++++++++++++++++++++++
 include/drm/drm_edid.h     | 18 ++++++++++--
 2 files changed, 73 insertions(+), 2 deletions(-)

Comments

Sam Ravnborg Sept. 6, 2021, 8:19 p.m. UTC | #1 
Hi Markus,

On Mon, Sep 06, 2021 at 09:35:26PM +0200, Markus Schneider-Pargmann wrote:
> This patch adds two helper functions that extract the frequency and word
> length from a struct cea_sad.
> 
> For these helper functions new defines are added that help translate the
> 'freq' and 'byte2' fields into real numbers.
> 
> Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
> ---
>  drivers/gpu/drm/drm_edid.c | 57 ++++++++++++++++++++++++++++++++++++++
>  include/drm/drm_edid.h     | 18 ++++++++++--
>  2 files changed, 73 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
> index 81d5f2524246..2389d34ce10e 100644
> --- a/drivers/gpu/drm/drm_edid.c
> +++ b/drivers/gpu/drm/drm_edid.c
> @@ -4666,6 +4666,63 @@ int drm_edid_to_speaker_allocation(struct edid *edid, u8 **sadb)
>  }
>  EXPORT_SYMBOL(drm_edid_to_speaker_allocation);
>  
> +/**
> + * drm_cea_sad_get_sample_rate - Extract the sample rate from cea_sad
> + * @sad: Pointer to the cea_sad struct
> + *
> + * Extracts the cea_sad frequency field and returns the sample rate in Hz.
> + *
> + * Return: Sample rate in Hz or a negative errno if parsing failed.
> + */
> +int drm_cea_sad_get_sample_rate(struct cea_sad *sad)

It would be nice to use const struct cea_sad *sad here.

> +{
> +	switch (sad->freq) {
> +	case CEA_SAD_FREQ_32KHZ:
> +		return 32000;
> +	case CEA_SAD_FREQ_44KHZ:
> +		return 44100;
> +	case CEA_SAD_FREQ_48KHZ:
> +		return 48000;
> +	case CEA_SAD_FREQ_88KHZ:
> +		return 88200;
> +	case CEA_SAD_FREQ_96KHZ:
> +		return 96000;
> +	case CEA_SAD_FREQ_176KHZ:
> +		return 176400;
> +	case CEA_SAD_FREQ_192KHZ:
> +		return 192000;
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +EXPORT_SYMBOL(drm_cea_sad_get_sample_rate);
> +
> +/**
> + * drm_cea_sad_get_uncompressed_word_length - Extract word length
> + * @sad: Pointer to the cea_sad struct
> + *
> + * Extracts the cea_sad byte2 field and returns the word length for an
> + * uncompressed stream.
> + *
> + * Note: This function may only be called for uncompressed audio.
Can you check or this and WARN (or drm_WARN) if this is not the case?

> + *
> + * Return: Word length in bits or a negative errno if parsing failed.
> + */
> +int drm_cea_sad_get_uncompressed_word_length(struct cea_sad *sad)
Again, consider to use const.

	Sam

> +{
> +	switch (sad->byte2) {
> +	case CEA_SAD_UNCOMPRESSED_WORD_16BIT:
> +		return 16;
> +	case CEA_SAD_UNCOMPRESSED_WORD_20BIT:
> +		return 20;
> +	case CEA_SAD_UNCOMPRESSED_WORD_24BIT:
> +		return 24;
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +EXPORT_SYMBOL(drm_cea_sad_get_uncompressed_word_length);
> +
>  /**
>   * drm_av_sync_delay - compute the HDMI/DP sink audio-video sync delay
>   * @connector: connector associated with the HDMI/DP sink
> diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h
> index 759328a5eeb2..bed091a749ef 100644
> --- a/include/drm/drm_edid.h
> +++ b/include/drm/drm_edid.h
> @@ -361,12 +361,24 @@ struct edid {
>  
>  /* Short Audio Descriptor */
>  struct cea_sad {
> -	u8 format;
> +	u8 format; /* See HDMI_AUDIO_CODING_TYPE_* */
>  	u8 channels; /* max number of channels - 1 */
> -	u8 freq;
> +	u8 freq; /* See CEA_SAD_FREQ_* */
>  	u8 byte2; /* meaning depends on format */
>  };
>  
> +#define CEA_SAD_FREQ_32KHZ  BIT(0)
> +#define CEA_SAD_FREQ_44KHZ  BIT(1)
> +#define CEA_SAD_FREQ_48KHZ  BIT(2)
> +#define CEA_SAD_FREQ_88KHZ  BIT(3)
> +#define CEA_SAD_FREQ_96KHZ  BIT(4)
> +#define CEA_SAD_FREQ_176KHZ BIT(5)
> +#define CEA_SAD_FREQ_192KHZ BIT(6)
> +
> +#define CEA_SAD_UNCOMPRESSED_WORD_16BIT BIT(0)
> +#define CEA_SAD_UNCOMPRESSED_WORD_20BIT BIT(1)
> +#define CEA_SAD_UNCOMPRESSED_WORD_24BIT BIT(2)
> +
>  struct drm_encoder;
>  struct drm_connector;
>  struct drm_connector_state;
> @@ -374,6 +386,8 @@ struct drm_display_mode;
>  
>  int drm_edid_to_sad(struct edid *edid, struct cea_sad **sads);
>  int drm_edid_to_speaker_allocation(struct edid *edid, u8 **sadb);
> +int drm_cea_sad_get_sample_rate(struct cea_sad *sad);
> +int drm_cea_sad_get_uncompressed_word_length(struct cea_sad *sad);
>  int drm_av_sync_delay(struct drm_connector *connector,
>  		      const struct drm_display_mode *mode);
>  
> -- 
> 2.33.0
Markus Schneider-Pargmann Sept. 7, 2021, 7:38 a.m. UTC | #2 
Hi Sam,

On Mon, Sep 06, 2021 at 10:19:00PM +0200, Sam Ravnborg wrote:
> Hi Markus,
> 
> On Mon, Sep 06, 2021 at 09:35:26PM +0200, Markus Schneider-Pargmann wrote:
> > This patch adds two helper functions that extract the frequency and word
> > length from a struct cea_sad.
> > 
> > For these helper functions new defines are added that help translate the
> > 'freq' and 'byte2' fields into real numbers.
> > 
> > Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
> > ---
> >  drivers/gpu/drm/drm_edid.c | 57 ++++++++++++++++++++++++++++++++++++++
> >  include/drm/drm_edid.h     | 18 ++++++++++--
> >  2 files changed, 73 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
> > index 81d5f2524246..2389d34ce10e 100644
> > --- a/drivers/gpu/drm/drm_edid.c
> > +++ b/drivers/gpu/drm/drm_edid.c
> > @@ -4666,6 +4666,63 @@ int drm_edid_to_speaker_allocation(struct edid *edid, u8 **sadb)
> >  }
> >  EXPORT_SYMBOL(drm_edid_to_speaker_allocation);
> >  
> > +/**
> > + * drm_cea_sad_get_sample_rate - Extract the sample rate from cea_sad
> > + * @sad: Pointer to the cea_sad struct
> > + *
> > + * Extracts the cea_sad frequency field and returns the sample rate in Hz.
> > + *
> > + * Return: Sample rate in Hz or a negative errno if parsing failed.
> > + */
> > +int drm_cea_sad_get_sample_rate(struct cea_sad *sad)
> 
> It would be nice to use const struct cea_sad *sad here.

Thanks, fixing it for the next version.

> 
> > +{
> > +	switch (sad->freq) {
> > +	case CEA_SAD_FREQ_32KHZ:
> > +		return 32000;
> > +	case CEA_SAD_FREQ_44KHZ:
> > +		return 44100;
> > +	case CEA_SAD_FREQ_48KHZ:
> > +		return 48000;
> > +	case CEA_SAD_FREQ_88KHZ:
> > +		return 88200;
> > +	case CEA_SAD_FREQ_96KHZ:
> > +		return 96000;
> > +	case CEA_SAD_FREQ_176KHZ:
> > +		return 176400;
> > +	case CEA_SAD_FREQ_192KHZ:
> > +		return 192000;
> > +	default:
> > +		return -EINVAL;
> > +	}
> > +}
> > +EXPORT_SYMBOL(drm_cea_sad_get_sample_rate);
> > +
> > +/**
> > + * drm_cea_sad_get_uncompressed_word_length - Extract word length
> > + * @sad: Pointer to the cea_sad struct
> > + *
> > + * Extracts the cea_sad byte2 field and returns the word length for an
> > + * uncompressed stream.
> > + *
> > + * Note: This function may only be called for uncompressed audio.
> Can you check or this and WARN (or drm_WARN) if this is not the case?

Good idea, I added a check, a DRM_WARN and return -EINVAL now.

Thanks,
Markus

> 
> > + *
> > + * Return: Word length in bits or a negative errno if parsing failed.
> > + */
> > +int drm_cea_sad_get_uncompressed_word_length(struct cea_sad *sad)
> Again, consider to use const.
> 
> 	Sam
> 
> > +{
> > +	switch (sad->byte2) {
> > +	case CEA_SAD_UNCOMPRESSED_WORD_16BIT:
> > +		return 16;
> > +	case CEA_SAD_UNCOMPRESSED_WORD_20BIT:
> > +		return 20;
> > +	case CEA_SAD_UNCOMPRESSED_WORD_24BIT:
> > +		return 24;
> > +	default:
> > +		return -EINVAL;
> > +	}
> > +}
> > +EXPORT_SYMBOL(drm_cea_sad_get_uncompressed_word_length);
> > +
> >  /**
> >   * drm_av_sync_delay - compute the HDMI/DP sink audio-video sync delay
> >   * @connector: connector associated with the HDMI/DP sink
> > diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h
> > index 759328a5eeb2..bed091a749ef 100644
> > --- a/include/drm/drm_edid.h
> > +++ b/include/drm/drm_edid.h
> > @@ -361,12 +361,24 @@ struct edid {
> >  
> >  /* Short Audio Descriptor */
> >  struct cea_sad {
> > -	u8 format;
> > +	u8 format; /* See HDMI_AUDIO_CODING_TYPE_* */
> >  	u8 channels; /* max number of channels - 1 */
> > -	u8 freq;
> > +	u8 freq; /* See CEA_SAD_FREQ_* */
> >  	u8 byte2; /* meaning depends on format */
> >  };
> >  
> > +#define CEA_SAD_FREQ_32KHZ  BIT(0)
> > +#define CEA_SAD_FREQ_44KHZ  BIT(1)
> > +#define CEA_SAD_FREQ_48KHZ  BIT(2)
> > +#define CEA_SAD_FREQ_88KHZ  BIT(3)
> > +#define CEA_SAD_FREQ_96KHZ  BIT(4)
> > +#define CEA_SAD_FREQ_176KHZ BIT(5)
> > +#define CEA_SAD_FREQ_192KHZ BIT(6)
> > +
> > +#define CEA_SAD_UNCOMPRESSED_WORD_16BIT BIT(0)
> > +#define CEA_SAD_UNCOMPRESSED_WORD_20BIT BIT(1)
> > +#define CEA_SAD_UNCOMPRESSED_WORD_24BIT BIT(2)
> > +
> >  struct drm_encoder;
> >  struct drm_connector;
> >  struct drm_connector_state;
> > @@ -374,6 +386,8 @@ struct drm_display_mode;
> >  
> >  int drm_edid_to_sad(struct edid *edid, struct cea_sad **sads);
> >  int drm_edid_to_speaker_allocation(struct edid *edid, u8 **sadb);
> > +int drm_cea_sad_get_sample_rate(struct cea_sad *sad);
> > +int drm_cea_sad_get_uncompressed_word_length(struct cea_sad *sad);
> >  int drm_av_sync_delay(struct drm_connector *connector,
> >  		      const struct drm_display_mode *mode);
> >  
> > -- 
> > 2.33.0
diff mbox series

Patch

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 81d5f2524246..2389d34ce10e 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -4666,6 +4666,63 @@  int drm_edid_to_speaker_allocation(struct edid *edid, u8 **sadb)
 }
 EXPORT_SYMBOL(drm_edid_to_speaker_allocation);
 
+/**
+ * drm_cea_sad_get_sample_rate - Extract the sample rate from cea_sad
+ * @sad: Pointer to the cea_sad struct
+ *
+ * Extracts the cea_sad frequency field and returns the sample rate in Hz.
+ *
+ * Return: Sample rate in Hz or a negative errno if parsing failed.
+ */
+int drm_cea_sad_get_sample_rate(struct cea_sad *sad)
+{
+	switch (sad->freq) {
+	case CEA_SAD_FREQ_32KHZ:
+		return 32000;
+	case CEA_SAD_FREQ_44KHZ:
+		return 44100;
+	case CEA_SAD_FREQ_48KHZ:
+		return 48000;
+	case CEA_SAD_FREQ_88KHZ:
+		return 88200;
+	case CEA_SAD_FREQ_96KHZ:
+		return 96000;
+	case CEA_SAD_FREQ_176KHZ:
+		return 176400;
+	case CEA_SAD_FREQ_192KHZ:
+		return 192000;
+	default:
+		return -EINVAL;
+	}
+}
+EXPORT_SYMBOL(drm_cea_sad_get_sample_rate);
+
+/**
+ * drm_cea_sad_get_uncompressed_word_length - Extract word length
+ * @sad: Pointer to the cea_sad struct
+ *
+ * Extracts the cea_sad byte2 field and returns the word length for an
+ * uncompressed stream.
+ *
+ * Note: This function may only be called for uncompressed audio.
+ *
+ * Return: Word length in bits or a negative errno if parsing failed.
+ */
+int drm_cea_sad_get_uncompressed_word_length(struct cea_sad *sad)
+{
+	switch (sad->byte2) {
+	case CEA_SAD_UNCOMPRESSED_WORD_16BIT:
+		return 16;
+	case CEA_SAD_UNCOMPRESSED_WORD_20BIT:
+		return 20;
+	case CEA_SAD_UNCOMPRESSED_WORD_24BIT:
+		return 24;
+	default:
+		return -EINVAL;
+	}
+}
+EXPORT_SYMBOL(drm_cea_sad_get_uncompressed_word_length);
+
 /**
  * drm_av_sync_delay - compute the HDMI/DP sink audio-video sync delay
  * @connector: connector associated with the HDMI/DP sink
diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h
index 759328a5eeb2..bed091a749ef 100644
--- a/include/drm/drm_edid.h
+++ b/include/drm/drm_edid.h
@@ -361,12 +361,24 @@  struct edid {
 
 /* Short Audio Descriptor */
 struct cea_sad {
-	u8 format;
+	u8 format; /* See HDMI_AUDIO_CODING_TYPE_* */
 	u8 channels; /* max number of channels - 1 */
-	u8 freq;
+	u8 freq; /* See CEA_SAD_FREQ_* */
 	u8 byte2; /* meaning depends on format */
 };
 
+#define CEA_SAD_FREQ_32KHZ  BIT(0)
+#define CEA_SAD_FREQ_44KHZ  BIT(1)
+#define CEA_SAD_FREQ_48KHZ  BIT(2)
+#define CEA_SAD_FREQ_88KHZ  BIT(3)
+#define CEA_SAD_FREQ_96KHZ  BIT(4)
+#define CEA_SAD_FREQ_176KHZ BIT(5)
+#define CEA_SAD_FREQ_192KHZ BIT(6)
+
+#define CEA_SAD_UNCOMPRESSED_WORD_16BIT BIT(0)
+#define CEA_SAD_UNCOMPRESSED_WORD_20BIT BIT(1)
+#define CEA_SAD_UNCOMPRESSED_WORD_24BIT BIT(2)
+
 struct drm_encoder;
 struct drm_connector;
 struct drm_connector_state;
@@ -374,6 +386,8 @@  struct drm_display_mode;
 
 int drm_edid_to_sad(struct edid *edid, struct cea_sad **sads);
 int drm_edid_to_speaker_allocation(struct edid *edid, u8 **sadb);
+int drm_cea_sad_get_sample_rate(struct cea_sad *sad);
+int drm_cea_sad_get_uncompressed_word_length(struct cea_sad *sad);
 int drm_av_sync_delay(struct drm_connector *connector,
 		      const struct drm_display_mode *mode);