[PATCH 2/3] drm/bridge: migrate bridge_chains to per-encoder file

[Tomi Valkeinen]

Hi,

On 06/10/2023 10:35, Neil Armstrong wrote:
> Hi,
> 
> On 04/09/2023 03:53, Dmitry Baryshkov wrote:
>> Instead of having a single file with all bridge chains, list bridges
>> under a corresponding per-encoder debugfs directory.
>>
>> Example of the listing:
>>
>> $ cat /sys/kernel/debug/dri/0/encoder-0/bridges
>> bridge[0]: dsi_mgr_bridge_funcs
>>     type: [0] Unknown
>>     ops: [0]
>> bridge[1]: lt9611uxc_bridge_funcs
>>     type: [11] HDMI-A
>>     OF: /soc at 0/geniqup at 9c0000/i2c at 994000/hdmi-bridge at 2b:lontium,lt9611uxc
>>     ops: [7] detect edid hpd
>>
>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
>> ---
>>   drivers/gpu/drm/drm_bridge.c  | 44 -----------------------------------
>>   drivers/gpu/drm/drm_debugfs.c | 39 ++++++++++++++++++++++++++++---
>>   include/drm/drm_bridge.h      |  2 --
>>   3 files changed, 36 insertions(+), 49 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
>> index 39e68e45bb12..cee3188adf3d 100644
>> --- a/drivers/gpu/drm/drm_bridge.c
>> +++ b/drivers/gpu/drm/drm_bridge.c
>> @@ -1347,50 +1347,6 @@ struct drm_bridge *of_drm_find_bridge(struct 
>> device_node *np)
>>   EXPORT_SYMBOL(of_drm_find_bridge);
>>   #endif
>> -#ifdef CONFIG_DEBUG_FS
>> -static int drm_bridge_chains_info(struct seq_file *m, void *data)
>> -{
>> -    struct drm_debugfs_entry *entry = m->private;
>> -    struct drm_device *dev = entry->dev;
>> -    struct drm_printer p = drm_seq_file_printer(m);
>> -    struct drm_mode_config *config = &dev->mode_config;
>> -    struct drm_encoder *encoder;
>> -    unsigned int bridge_idx = 0;
>> -
>> -    list_for_each_entry(encoder, &config->encoder_list, head) {
>> -        struct drm_bridge *bridge;
>> -
>> -        drm_printf(&p, "encoder[%u]\n", encoder->base.id);
>> -
>> -        drm_for_each_bridge_in_chain(encoder, bridge) {
>> -            drm_printf(&p, "\tbridge[%u] type: %u, ops: %#x",
>> -                   bridge_idx, bridge->type, bridge->ops);
>> -
>> -#ifdef CONFIG_OF
>> -            if (bridge->of_node)
>> -                drm_printf(&p, ", OF: %pOFfc", bridge->of_node);
>> -#endif
>> -
>> -            drm_printf(&p, "\n");
>> -
>> -            bridge_idx++;
>> -        }
>> -    }
>> -
>> -    return 0;
>> -}
>> -
>> -static const struct drm_debugfs_info drm_bridge_debugfs_list[] = {
>> -    { "bridge_chains", drm_bridge_chains_info, 0 },
>> -};
>> -
>> -void drm_bridge_debugfs_init(struct drm_minor *minor)
>> -{
>> -    drm_debugfs_add_files(minor->dev, drm_bridge_debugfs_list,
>> -                  ARRAY_SIZE(drm_bridge_debugfs_list));
>> -}
>> -#endif
>> -
>>   MODULE_AUTHOR("Ajay Kumar <ajaykumar.rs at samsung.com>");
>>   MODULE_DESCRIPTION("DRM bridge infrastructure");
>>   MODULE_LICENSE("GPL and additional rights");
>> diff --git a/drivers/gpu/drm/drm_debugfs.c 
>> b/drivers/gpu/drm/drm_debugfs.c
>> index cf7f33bdc963..70913067406d 100644
>> --- a/drivers/gpu/drm/drm_debugfs.c
>> +++ b/drivers/gpu/drm/drm_debugfs.c
>> @@ -273,10 +273,8 @@ int drm_debugfs_init(struct drm_minor *minor, int 
>> minor_id,
>>       drm_debugfs_add_files(minor->dev, drm_debugfs_list, 
>> DRM_DEBUGFS_ENTRIES);
>> -    if (drm_drv_uses_atomic_modeset(dev)) {
>> +    if (drm_drv_uses_atomic_modeset(dev))
>>           drm_atomic_debugfs_init(minor);
>> -        drm_bridge_debugfs_init(minor);
>> -    }
>>       if (drm_core_check_feature(dev, DRIVER_MODESET)) {
>>           drm_framebuffer_debugfs_init(minor);
>> @@ -603,6 +601,37 @@ void drm_debugfs_crtc_remove(struct drm_crtc *crtc)
>>       crtc->debugfs_entry = NULL;
>>   }
>> +static int bridges_show(struct seq_file *m, void *data)
>> +{
>> +    struct drm_encoder *encoder = m->private;
>> +    struct drm_bridge *bridge;
>> +    unsigned int idx = 0;
>> +
>> +    drm_for_each_bridge_in_chain(encoder, bridge) {
>> +        seq_printf(m, "bridge[%d]: %ps\n", idx++, bridge->funcs);
>> +        seq_printf(m, "\ttype: [%d] %s\n",
>> +               bridge->type,
>> +               drm_get_connector_type_name(bridge->type));
>> +#ifdef CONFIG_OF
>> +        if (bridge->of_node)
>> +            seq_printf(m, "\tOF: %pOFfc\n", bridge->of_node);
>> +#endif
>> +        seq_printf(m, "\tops: [0x%x]", bridge->ops);
>> +        if (bridge->ops & DRM_BRIDGE_OP_DETECT)
>> +            seq_puts(m, " detect");
>> +        if (bridge->ops & DRM_BRIDGE_OP_EDID)
>> +            seq_puts(m, " edid");
>> +        if (bridge->ops & DRM_BRIDGE_OP_HPD)
>> +            seq_puts(m, " hpd");
>> +        if (bridge->ops & DRM_BRIDGE_OP_MODES)
>> +            seq_puts(m, " modes");
>> +        seq_puts(m, "\n");
>> +    }
>> +
>> +    return 0;
>> +}
>> +DEFINE_SHOW_ATTRIBUTE(bridges);
>> +
>>   void drm_debugfs_encoder_add(struct drm_encoder *encoder)
>>   {
>>       struct drm_minor *minor = encoder->dev->primary;
>> @@ -618,6 +647,10 @@ void drm_debugfs_encoder_add(struct drm_encoder 
>> *encoder)
>>       encoder->debugfs_entry = root;
>> +    /* bridges list */
>> +    debugfs_create_file("bridges", 0444, root, encoder,
>> +                &bridges_fops);
>> +
>>       if (encoder->funcs->debugfs_init)
>>           encoder->funcs->debugfs_init(encoder, root);
>>   }
>> diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
>> index c339fc85fd07..902bc3f99c2a 100644
>> --- a/include/drm/drm_bridge.h
>> +++ b/include/drm/drm_bridge.h
>> @@ -950,6 +950,4 @@ static inline struct drm_bridge 
>> *drmm_of_get_bridge(struct drm_device *drm,
>>   }
>>   #endif
>> -void drm_bridge_debugfs_init(struct drm_minor *minor);
>> -
>>   #endif
> 
> It would be nice to have a review from Tomi since he pushed the bridge 
> chains debugfs.
> 
> Apart that it looks fine:
> Reviewed-by: Neil Armstrong <neil.armstrong at linaro.org>

This change does more than move the code to per-encoder debugfs file: it 
changes the formatting, adding textual representations for the flags, 
and drops the use of drm_printer.

I'd prefer to have such changes separately, but as it's a small patch I 
guess it's fine-ish. But they should at least be mentioned in the patch 
description.

With that addressed:

Reviewed-by: Tomi Valkeinen <tomi.valkeinen at ideasonboard.com>

  Tomi