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

[Dmitry Baryshkov]

On 06/10/2023 10:51, Tomi Valkeinen wrote:
> 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.

Fair enough, I'll add this to the commit message. Thank you!

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

-- 
With best wishes
Dmitry