<html><body><p> <pre> On Tue, 2025-02-11 at 12:34 +0100, AngeloGioacchino Del Regno wrote: > External email : Please do not click links or open attachments until you have verified the sender or the content. > > > Implement the Automated Built-In Self-Test ABIST functionality > provided by the HDMIv2 IP and expose it through the "hdmi_abist" > debugfs file. > > Write "1" to this file to activate ABIST, or "0" to deactivate. Describe what we would see when activate ABIST. Give some example of when to use it. > > Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> > --- > drivers/gpu/drm/mediatek/mtk_hdmi_v2.c | 123 +++++++++++++++++++++++++ > 1 file changed, 123 insertions(+) > > diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi_v2.c b/drivers/gpu/drm/mediatek/mtk_hdmi_v2.c > index 36b7f8d8d218..f4a086b92dae 100644 > --- a/drivers/gpu/drm/mediatek/mtk_hdmi_v2.c > +++ b/drivers/gpu/drm/mediatek/mtk_hdmi_v2.c > @@ -1170,6 +1170,128 @@ static int mtk_hdmi_v2_hdmi_write_infoframe(struct drm_bridge *bridge, > return 0; > } > > +static int mtk_hdmi_v2_set_abist(struct mtk_hdmi *hdmi, bool enable) > +{ > + struct drm_display_mode *mode = &hdmi->mode; > + int abist_format = -EINVAL; > + bool interlaced; > + > + if (!enable) { > + regmap_clear_bits(hdmi->regs, TOP_CFG00, HDMI_ABIST_ENABLE); > + return 0; > + } > + > + if (!mode->hdisplay || !mode->vdisplay) > + return -EINVAL; > + > + interlaced = mode->flags & DRM_MODE_FLAG_INTERLACE; > + > + switch (mode->hdisplay) { > + case 720: > + if (mode->vdisplay == 480) > + abist_format = 2; > + else if (mode->vdisplay == 576) > + abist_format = 11; > + break; > + case 1280: > + if (mode->vdisplay == 720) > + abist_format = 3; > + break; > + case 1440: > + if (mode->vdisplay == 480) > + abist_format = interlaced ? 5 : 9; > + else if (mode->vdisplay == 576) > + abist_format = interlaced ? 14 : 18; > + break; > + case 1920: > + if (mode->vdisplay == 1080) > + abist_format = interlaced ? 4 : 10; > + break; > + case 3840: > + if (mode->vdisplay == 2160) > + abist_format = 25; > + break; > + case 4096: > + if (mode->vdisplay == 2160) > + abist_format = 26; > + break; > + default: > + break; > + } > + if (!abist_format) abist_format's initial value is -EINVAL, so this checking would never be true. Let abist_format's initial value be zero. Regards, CK > + return -EINVAL; > + > + regmap_update_bits(hdmi->regs, TOP_CFG00, HDMI_ABIST_VIDEO_FORMAT, > + FIELD_PREP(HDMI_ABIST_VIDEO_FORMAT, abist_format)); > + regmap_set_bits(hdmi->regs, TOP_CFG00, HDMI_ABIST_ENABLE); > + return 0; > +} > + > +static int mtk_hdmi_v2_debug_abist_show(struct seq_file *m, void *arg) > +{ > + struct mtk_hdmi *hdmi = m->private; > + bool en; > + u32 val; > + int ret; > + > + if (!hdmi) > + return -EINVAL; > + > + ret = regmap_read(hdmi->regs, TOP_CFG00, &val); > + if (ret) > + return ret; > + > + en = FIELD_GET(HDMI_ABIST_ENABLE, val); > + > + seq_printf(m, "HDMI Automated Built-In Self Test: %s\n", > + en ? "Enabled" : "Disabled"); > + > + return 0; > +} > + > +static ssize_t mtk_hdmi_v2_debug_abist_write(struct file *file, > + const char __user *ubuf, > + size_t len, loff_t *offp) > +{ > + struct seq_file *m = file->private_data; > + int ret; > + u32 en; > + > + if (!m || !m->private || *offp) > + return -EINVAL; > + > + ret = kstrtouint_from_user(ubuf, len, 0, &en); > + if (ret) > + return ret; > + > + if (en < 0 || en > 1) > + return -EINVAL; > + > + mtk_hdmi_v2_set_abist((struct mtk_hdmi *)m->private, en); > + return len; > +} > + > +static int mtk_hdmi_v2_debug_abist_open(struct inode *inode, struct file *file) > +{ > + return single_open(file, mtk_hdmi_v2_debug_abist_show, inode->i_private); > +} > + > +static const struct file_operations mtk_hdmi_debug_abist_fops = { > + .owner = THIS_MODULE, > + .open = mtk_hdmi_v2_debug_abist_open, > + .read = seq_read, > + .write = mtk_hdmi_v2_debug_abist_write, > + .llseek = seq_lseek, > + .release = single_release, > +}; > + > +static void mtk_hdmi_v2_debugfs_init(struct drm_bridge *bridge, struct dentry *root) > +{ > + struct mtk_hdmi *dpi = hdmi_ctx_from_bridge(bridge); > + > + debugfs_create_file("hdmi_abist", 0640, root, dpi, &mtk_hdmi_debug_abist_fops); > +} > + > static const struct drm_bridge_funcs mtk_v2_hdmi_bridge_funcs = { > .attach = mtk_hdmi_v2_bridge_attach, > .detach = mtk_hdmi_v2_bridge_detach, > @@ -1189,6 +1311,7 @@ static const struct drm_bridge_funcs mtk_v2_hdmi_bridge_funcs = { > .hdmi_tmds_char_rate_valid = mtk_hdmi_v2_hdmi_tmds_char_rate_valid, > .hdmi_clear_infoframe = mtk_hdmi_v2_hdmi_clear_infoframe, > .hdmi_write_infoframe = mtk_hdmi_v2_hdmi_write_infoframe, > + .debugfs_init = mtk_hdmi_v2_debugfs_init, > }; > > /* > -- > 2.48.1 > </pre> </p></body></html><pre>************* MEDIATEK Confidentiality Notice ******************** The information contained in this e-mail message (including any attachments) may be confidential, proprietary, privileged, or otherwise exempt from disclosure under applicable laws. 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