On 28/08/2024 17:08, Jani Nikula wrote:
> On Wed, 28 Aug 2024, Hans Verkuil <hverkuil-cisco@xxxxxxxxx> wrote:
>> Add new helpers to export received or transmitted HDMI InfoFrames to
>> debugfs.
>>
>> This complements similar code in drm where the transmitted HDMI infoframes
>> are exported to debugfs.
>>
>> The same names have been used as in drm, so this is consistent.
>>
>> The exported infoframes can be parsed with the edid-decode utility.
>>
>> Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
>> ---
>> drivers/media/v4l2-core/v4l2-dv-timings.c | 63 +++++++++++++++++++++++
>> include/media/v4l2-dv-timings.h | 48 +++++++++++++++++
>> 2 files changed, 111 insertions(+)
>>
>> diff --git a/drivers/media/v4l2-core/v4l2-dv-timings.c b/drivers/media/v4l2-core/v4l2-dv-timings.c
>> index 942d0005c55e..86a8627f4bcc 100644
>> --- a/drivers/media/v4l2-core/v4l2-dv-timings.c
>> +++ b/drivers/media/v4l2-core/v4l2-dv-timings.c
>> @@ -1154,3 +1154,66 @@ int v4l2_phys_addr_validate(u16 phys_addr, u16 *parent, u16 *port)
>> return 0;
>> }
>> EXPORT_SYMBOL_GPL(v4l2_phys_addr_validate);
>> +
>> +#ifdef CONFIG_DEBUG_FS
>> +
>> +#define DEBUGFS_FOPS(type, flag) \
>> +static ssize_t \
>> +infoframe_read_##type(struct file *filp, \
>> + char __user *ubuf, size_t count, loff_t *ppos) \
>> +{ \
>> + struct v4l2_debugfs_if *infoframes = filp->private_data; \
>> + \
>> + return infoframes->if_read((flag), infoframes->priv, filp, \
>> + ubuf, count, ppos); \
>> +} \
>> + \
>> +static const struct file_operations infoframe_##type##_fops = { \
>> + .owner = THIS_MODULE, \
>> + .open = simple_open, \
>> + .read = infoframe_read_##type, \
>> +}
>> +
>> +DEBUGFS_FOPS(avi, V4L2_DEBUGFS_IF_AVI);
>> +DEBUGFS_FOPS(audio, V4L2_DEBUGFS_IF_AUDIO);
>> +DEBUGFS_FOPS(spd, V4L2_DEBUGFS_IF_SPD);
>> +DEBUGFS_FOPS(hdmi, V4L2_DEBUGFS_IF_HDMI);
>> +
>> +struct v4l2_debugfs_if *v4l2_debugfs_if_alloc(struct dentry *root, u32 if_types,
>> + void *priv,
>> + v4l2_debugfs_if_read_t if_read)
>> +{
>> + struct v4l2_debugfs_if *infoframes;
>> +
>> + if (IS_ERR_OR_NULL(root) || !if_types || !if_read)
>> + return NULL;
>> +
>> + infoframes = kzalloc(sizeof(*infoframes), GFP_KERNEL);
>> + if (!infoframes)
>> + return NULL;
>> +
>> + infoframes->if_dir = debugfs_create_dir("infoframes", root);
>> + infoframes->priv = priv;
>> + infoframes->if_read = if_read;
>> + if (if_types & V4L2_DEBUGFS_IF_AVI)
>> + debugfs_create_file("avi", 0400, infoframes->if_dir, infoframes, &infoframe_avi_fops);
>> + if (if_types & V4L2_DEBUGFS_IF_AUDIO)
>> + debugfs_create_file("audio", 0400, infoframes->if_dir, infoframes, &infoframe_audio_fops);
>> + if (if_types & V4L2_DEBUGFS_IF_SPD)
>> + debugfs_create_file("spd", 0400, infoframes->if_dir, infoframes, &infoframe_spd_fops);
>> + if (if_types & V4L2_DEBUGFS_IF_HDMI)
>> + debugfs_create_file("hdmi", 0400, infoframes->if_dir, infoframes, &infoframe_hdmi_fops);
>> + return infoframes;
>> +}
>> +EXPORT_SYMBOL_GPL(v4l2_debugfs_if_alloc);
>> +
>> +void v4l2_debugfs_if_free(struct v4l2_debugfs_if *infoframes)
>> +{
>> + if (infoframes) {
>> + debugfs_remove_recursive(infoframes->if_dir);
>> + kfree(infoframes);
>> + }
>> +}
>> +EXPORT_SYMBOL_GPL(v4l2_debugfs_if_free);
>> +
>> +#endif
>> diff --git a/include/media/v4l2-dv-timings.h b/include/media/v4l2-dv-timings.h
>> index 8fa963326bf6..13830411bd6c 100644
>> --- a/include/media/v4l2-dv-timings.h
>> +++ b/include/media/v4l2-dv-timings.h
>> @@ -8,6 +8,7 @@
>> #ifndef __V4L2_DV_TIMINGS_H
>> #define __V4L2_DV_TIMINGS_H
>>
>> +#include <linux/debugfs.h>
>
> Please don't include headers from headers if you can get by with forward
> declarations.
Done.
>
> I recently discovered a lot of drm depending on getting seq_file.h and
> debugfs.h via media/cec.h...
Patches are welcome!
Regards,
Hans
>
> BR,
> Jani.
>
>
>> #include <linux/videodev2.h>
>>
>> /**
>> @@ -251,4 +252,51 @@ void v4l2_set_edid_phys_addr(u8 *edid, unsigned int size, u16 phys_addr);
>> u16 v4l2_phys_addr_for_input(u16 phys_addr, u8 input);
>> int v4l2_phys_addr_validate(u16 phys_addr, u16 *parent, u16 *port);
>>
>> +/* Add support for exporting InfoFrames to debugfs */
>> +
>> +/*
>> + * HDMI InfoFrames start with a 3 byte header, then a checksum,
>> + * followed by the actual IF payload.
>> + *
>> + * The payload length is limited to 30 bytes according to the HDMI spec,
>> + * but since the length is encoded in 5 bits, it can be 31 bytes theoretically.
>> + * So set the max length as 31 + 3 (header) + 1 (checksum) = 35.
>> + */
>> +#define V4L2_DEBUGFS_IF_MAX_LEN (35)
>> +
>> +#define V4L2_DEBUGFS_IF_AVI BIT(0)
>> +#define V4L2_DEBUGFS_IF_AUDIO BIT(1)
>> +#define V4L2_DEBUGFS_IF_SPD BIT(2)
>> +#define V4L2_DEBUGFS_IF_HDMI BIT(3)
>> +
>> +typedef ssize_t (*v4l2_debugfs_if_read_t)(u32 type, void *priv,
>> + struct file *filp, char __user *ubuf,
>> + size_t count, loff_t *ppos);
>> +
>> +struct v4l2_debugfs_if {
>> + struct dentry *if_dir;
>> + void *priv;
>> +
>> + v4l2_debugfs_if_read_t if_read;
>> +};
>> +
>> +#ifdef CONFIG_DEBUG_FS
>> +struct v4l2_debugfs_if *v4l2_debugfs_if_alloc(struct dentry *root, u32 if_types,
>> + void *priv,
>> + v4l2_debugfs_if_read_t if_read);
>> +void v4l2_debugfs_if_free(struct v4l2_debugfs_if *infoframes);
>> +#else
>> +static inline
>> +struct v4l2_debugfs_if *v4l2_debugfs_if_alloc(struct dentry *root, u32 if_types,
>> + void *priv,
>> + v4l2_debugfs_if_read_t if_read)
>> +{
>> + return NULL;
>> +}
>> +
>> +static inline void v4l2_debugfs_if_free(struct v4l2_debugfs_if *infoframes)
>> +{
>> +}
>> +#endif
>> +
>> #endif
>
