Re: [PATCH v4 07/11] drm/meson: meson_dw_hdmi: add bridge and switch to drm_bridge_funcs

From: Neil Armstrong
Date: Fri Feb 07 2020 - 10:36:09 EST


On 07/02/2020 15:57, Boris Brezillon wrote:
> On Thu, 6 Feb 2020 20:18:30 +0100
> Neil Armstrong <narmstrong@xxxxxxxxxxxx> wrote:
>
>> Switch the dw-hdmi driver to drm_bridge_funcs by implementing a new local
>> bridge, connecting it to the dw-hdmi bridge, then implement the
>> atomic_get_input_bus_fmts/atomic_get_output_bus_fmts.
>>
>> Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
>> ---
>> drivers/gpu/drm/meson/meson_dw_hdmi.c | 105 +++++++++++++++++++++-----
>> 1 file changed, 85 insertions(+), 20 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/meson/meson_dw_hdmi.c b/drivers/gpu/drm/meson/meson_dw_hdmi.c
>> index 3bb7ffe5fc39..4b3809626f7e 100644
>> --- a/drivers/gpu/drm/meson/meson_dw_hdmi.c
>> +++ b/drivers/gpu/drm/meson/meson_dw_hdmi.c
>> @@ -16,6 +16,7 @@
>>
>> #include <drm/bridge/dw_hdmi.h>
>> #include <drm/drm_atomic_helper.h>
>> +#include <drm/drm_bridge.h>
>> #include <drm/drm_device.h>
>> #include <drm/drm_edid.h>
>> #include <drm/drm_probe_helper.h>
>> @@ -135,6 +136,7 @@ struct meson_dw_hdmi_data {
>>
>> struct meson_dw_hdmi {
>> struct drm_encoder encoder;
>> + struct drm_bridge bridge;
>> struct dw_hdmi_plat_data dw_plat_data;
>> struct meson_drm *priv;
>> struct device *dev;
>> @@ -151,6 +153,8 @@ struct meson_dw_hdmi {
>> };
>> #define encoder_to_meson_dw_hdmi(x) \
>> container_of(x, struct meson_dw_hdmi, encoder)
>> +#define bridge_to_meson_dw_hdmi(x) \
>> + container_of(x, struct meson_dw_hdmi, bridge)
>>
>> static inline int dw_hdmi_is_compatible(struct meson_dw_hdmi *dw_hdmi,
>> const char *compat)
>> @@ -368,7 +372,7 @@ static inline void meson_dw_hdmi_phy_reset(struct meson_dw_hdmi *dw_hdmi)
>> }
>>
>> static void dw_hdmi_set_vclk(struct meson_dw_hdmi *dw_hdmi,
>> - struct drm_display_mode *mode)
>> + const struct drm_display_mode *mode)
>> {
>> struct meson_drm *priv = dw_hdmi->priv;
>> int vic = drm_match_cea_mode(mode);
>> @@ -663,6 +667,10 @@ dw_hdmi_mode_valid(struct drm_connector *connector,
>>
>> /* Encoder */
>>
>> +static const u32 meson_dw_hdmi_out_bus_fmts[] = {
>> + MEDIA_BUS_FMT_YUV8_1X24,
>> +};
>> +
>> static void meson_venc_hdmi_encoder_destroy(struct drm_encoder *encoder)
>> {
>> drm_encoder_cleanup(encoder);
>> @@ -672,16 +680,63 @@ static const struct drm_encoder_funcs meson_venc_hdmi_encoder_funcs = {
>> .destroy = meson_venc_hdmi_encoder_destroy,
>> };
>>
>> -static int meson_venc_hdmi_encoder_atomic_check(struct drm_encoder *encoder,
>> +static u32 *
>> +meson_venc_hdmi_encoder_get_out_bus_fmts(struct drm_bridge *bridge,
>> + struct drm_bridge_state *bridge_state,
>> + struct drm_crtc_state *crtc_state,
>> + struct drm_connector_state *conn_state,
>> + unsigned int *num_output_fmts)
>> +{
>> + u32 *output_fmts;
>> +
>> + *num_output_fmts = ARRAY_SIZE(meson_dw_hdmi_out_bus_fmts);
>> + output_fmts = kcalloc(*num_output_fmts, sizeof(*output_fmts),
>> + GFP_KERNEL);
>> + if (!output_fmts)
>> + return NULL;
>> +
>> + memcpy(output_fmts, meson_dw_hdmi_out_bus_fmts, *num_output_fmts);
>> +
>> + return output_fmts;
>> +}
>> +
>> +static u32 *
>> +meson_venc_hdmi_encoder_get_inp_bus_fmts(struct drm_bridge *bridge,
>> + struct drm_bridge_state *bridge_state,
>> + struct drm_crtc_state *crtc_state,
>> + struct drm_connector_state *conn_state,
>> + u32 output_fmt,
>> + unsigned int *num_input_fmts)
>> +{
>> + u32 *input_fmts = NULL;
>> +
>> + if (output_fmt == meson_dw_hdmi_out_bus_fmts[0]) {
>> + *num_input_fmts = 1;
>> + input_fmts = kcalloc(*num_input_fmts,
>> + sizeof(*input_fmts),
>> + GFP_KERNEL);
>> + if (!input_fmts)
>> + return NULL;
>> +
>> + input_fmts[0] = output_fmt;
>> + } else {
>> + *num_input_fmts = 0;
>> + }
>> +
>> + return input_fmts;
>> +}
>> +
>> +static int meson_venc_hdmi_encoder_atomic_check(struct drm_bridge *bridge,
>> + struct drm_bridge_state *bridge_state,
>> struct drm_crtc_state *crtc_state,
>> struct drm_connector_state *conn_state)
>> {
>> return 0;
>> }
>>
>> -static void meson_venc_hdmi_encoder_disable(struct drm_encoder *encoder)
>> +static void meson_venc_hdmi_encoder_disable(struct drm_bridge *bridge)
>> {
>> - struct meson_dw_hdmi *dw_hdmi = encoder_to_meson_dw_hdmi(encoder);
>> + struct meson_dw_hdmi *dw_hdmi = bridge_to_meson_dw_hdmi(bridge);
>> struct meson_drm *priv = dw_hdmi->priv;
>>
>> DRM_DEBUG_DRIVER("\n");
>> @@ -693,9 +748,9 @@ static void meson_venc_hdmi_encoder_disable(struct drm_encoder *encoder)
>> writel_relaxed(0, priv->io_base + _REG(ENCP_VIDEO_EN));
>> }
>>
>> -static void meson_venc_hdmi_encoder_enable(struct drm_encoder *encoder)
>> +static void meson_venc_hdmi_encoder_enable(struct drm_bridge *bridge)
>> {
>> - struct meson_dw_hdmi *dw_hdmi = encoder_to_meson_dw_hdmi(encoder);
>> + struct meson_dw_hdmi *dw_hdmi = bridge_to_meson_dw_hdmi(bridge);
>> struct meson_drm *priv = dw_hdmi->priv;
>>
>> DRM_DEBUG_DRIVER("%s\n", priv->venc.hdmi_use_enci ? "VENCI" : "VENCP");
>> @@ -706,11 +761,11 @@ static void meson_venc_hdmi_encoder_enable(struct drm_encoder *encoder)
>> writel_relaxed(1, priv->io_base + _REG(ENCP_VIDEO_EN));
>> }
>>
>> -static void meson_venc_hdmi_encoder_mode_set(struct drm_encoder *encoder,
>> - struct drm_display_mode *mode,
>> - struct drm_display_mode *adjusted_mode)
>> +static void meson_venc_hdmi_encoder_mode_set(struct drm_bridge *bridge,
>> + const struct drm_display_mode *mode,
>> + const struct drm_display_mode *adjusted_mode)
>> {
>> - struct meson_dw_hdmi *dw_hdmi = encoder_to_meson_dw_hdmi(encoder);
>> + struct meson_dw_hdmi *dw_hdmi = bridge_to_meson_dw_hdmi(bridge);
>> struct meson_drm *priv = dw_hdmi->priv;
>> int vic = drm_match_cea_mode(mode);
>>
>> @@ -726,12 +781,16 @@ static void meson_venc_hdmi_encoder_mode_set(struct drm_encoder *encoder,
>> writel_relaxed(0, priv->io_base + _REG(VPU_HDMI_FMT_CTRL));
>> }
>>
>> -static const struct drm_encoder_helper_funcs
>> - meson_venc_hdmi_encoder_helper_funcs = {
>> - .atomic_check = meson_venc_hdmi_encoder_atomic_check,
>> - .disable = meson_venc_hdmi_encoder_disable,
>> - .enable = meson_venc_hdmi_encoder_enable,
>> - .mode_set = meson_venc_hdmi_encoder_mode_set,
>> +static const struct drm_bridge_funcs meson_venc_hdmi_encoder_bridge_funcs = {
>> + .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
>> + .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
>> + .atomic_get_output_bus_fmts = meson_venc_hdmi_encoder_get_out_bus_fmts,
>
> Hm, can this bridge element be connected directly to the HDMI connector
> without the dw-hdmi bridge in the middle? If that's not the case, then
> you probably don't have to implement ->atomic_get_output_bus_fmts()
> (only used on the last bridge element).

No, the HDMI bridge is mandatory here.

Ok, makes sense, I'll remove it then.

Neil

>
>> + .atomic_get_input_bus_fmts = meson_venc_hdmi_encoder_get_inp_bus_fmts,
>> + .atomic_reset = drm_atomic_helper_bridge_reset,
>> + .atomic_check = meson_venc_hdmi_encoder_atomic_check,
>> + .enable = meson_venc_hdmi_encoder_enable,
>> + .disable = meson_venc_hdmi_encoder_disable,
>> + .mode_set = meson_venc_hdmi_encoder_mode_set,
>> };
>>
>> /* DW HDMI Regmap */
>> @@ -852,6 +911,7 @@ static int meson_dw_hdmi_bind(struct device *dev, struct device *master,
>> struct drm_device *drm = data;
>> struct meson_drm *priv = drm->dev_private;
>> struct dw_hdmi_plat_data *dw_plat_data;
>> + struct drm_bridge *next_bridge;
>> struct drm_encoder *encoder;
>> struct resource *res;
>> int irq;
>> @@ -953,8 +1013,6 @@ static int meson_dw_hdmi_bind(struct device *dev, struct device *master,
>>
>> /* Encoder */
>>
>> - drm_encoder_helper_add(encoder, &meson_venc_hdmi_encoder_helper_funcs);
>> -
>> ret = drm_encoder_init(drm, encoder, &meson_venc_hdmi_encoder_funcs,
>> DRM_MODE_ENCODER_TMDS, "meson_hdmi");
>> if (ret) {
>> @@ -962,6 +1020,9 @@ static int meson_dw_hdmi_bind(struct device *dev, struct device *master,
>> return ret;
>> }
>>
>> + meson_dw_hdmi->bridge.funcs = &meson_venc_hdmi_encoder_bridge_funcs;
>> + drm_bridge_attach(encoder, &meson_dw_hdmi->bridge, NULL);
>> +
>> encoder->possible_crtcs = BIT(0);
>>
>> DRM_DEBUG_DRIVER("encoder initialized\n");
>> @@ -984,11 +1045,15 @@ static int meson_dw_hdmi_bind(struct device *dev, struct device *master,
>>
>> platform_set_drvdata(pdev, meson_dw_hdmi);
>>
>> - meson_dw_hdmi->hdmi = dw_hdmi_bind(pdev, encoder,
>> - &meson_dw_hdmi->dw_plat_data);
>> + meson_dw_hdmi->hdmi = dw_hdmi_probe(pdev,
>> + &meson_dw_hdmi->dw_plat_data);
>> if (IS_ERR(meson_dw_hdmi->hdmi))
>> return PTR_ERR(meson_dw_hdmi->hdmi);
>>
>> + next_bridge = of_drm_find_bridge(pdev->dev.of_node);
>> + if (next_bridge)
>> + drm_bridge_attach(encoder, next_bridge, &meson_dw_hdmi->bridge);
>> +
>> DRM_DEBUG_DRIVER("HDMI controller initialized\n");
>>
>> return 0;
>