From nobody Tue Dec 16 14:42:25 2025 Received: from lelvem-ot02.ext.ti.com (lelvem-ot02.ext.ti.com [198.47.23.235]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 089EF1E0DE2 for ; Thu, 29 May 2025 11:04:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.47.23.235 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748516697; cv=none; b=KxihhRiX3OJ/faoY0UvqE1YW6LMBK6NH0sYP7JuS+0ptsgTCtFCc8fNp3WTcgdUAuR5UM/CJ67GW08Eib2Ui9ORACHgnFRlpn32kXBdizpVqTnUAwI8ZozfgVZYCt7v9IWq9okn7exWLii6X3kcy5RiYTZ+YLll6+hQW6MRjdX8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748516697; c=relaxed/simple; bh=L7eeCaEmQT3B2EkVt74tDBVVWouAKiKcV7oF52jndK8=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=Tfy8xP3/2bkZeN+YtBO5fbZHmeP13UQlxVF+5puHBbOfkiH4k5furCrg6bQlPAI8EI9vL9CSQ+xBEuFf4sAvpKAw6+0AyU8dEjaj3wtznGWUU367VXXQwooc4iFk3etJoR7laheyMYv+HoIkfWLJEImGc2NuGh1ciEsGrJfTpwY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ti.com; spf=pass smtp.mailfrom=ti.com; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b=wTad5+HL; arc=none smtp.client-ip=198.47.23.235 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ti.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ti.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="wTad5+HL" Received: from fllvem-sh04.itg.ti.com ([10.64.41.54]) by lelvem-ot02.ext.ti.com (8.15.2/8.15.2) with ESMTP id 54TB4KGp2383070; Thu, 29 May 2025 06:04:20 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1748516660; bh=Iw23YeKhX7fGnl9l2Fbn9RFA0j/KiCK+ixD/+jWdDSA=; h=From:To:CC:Subject:Date; b=wTad5+HLpT9jGceTDpzarKEOqfihDSBuuMvbGxl958WSgj1qdJbHPTnWkqw014AiN bcW7aRxPuAy8BCyE8QKUmT0X+whcZaggLpIgpieY96gVhP/xX4zbuUmKXmpm60UQs5 wmNe1czMhsLr6fW3KrCGIrALxuixis0zutrUJQJo= Received: from DFLE103.ent.ti.com (dfle103.ent.ti.com [10.64.6.24]) by fllvem-sh04.itg.ti.com (8.18.1/8.18.1) with ESMTPS id 54TB4JR0103762 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA256 bits=128 verify=FAIL); Thu, 29 May 2025 06:04:19 -0500 Received: from DFLE115.ent.ti.com (10.64.6.36) by DFLE103.ent.ti.com (10.64.6.24) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23; Thu, 29 May 2025 06:04:19 -0500 Received: from lelvem-mr06.itg.ti.com (10.180.75.8) by DFLE115.ent.ti.com (10.64.6.36) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23 via Frontend Transport; Thu, 29 May 2025 06:04:19 -0500 Received: from localhost (jayesh-hp-z2-tower-g5-workstation.dhcp.ti.com [172.24.227.14]) by lelvem-mr06.itg.ti.com (8.18.1/8.18.1) with ESMTP id 54TB4IpD1450759; Thu, 29 May 2025 06:04:19 -0500 From: Jayesh Choudhary To: , , , , , , , , CC: , , , , , , , , , , , Subject: [PATCH v3] drm/bridge: ti-sn65dsi86: Add HPD for DisplayPort connector type Date: Thu, 29 May 2025 16:34:18 +0530 Message-ID: <20250529110418.481756-1-j-choudhary@ti.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-C2ProcessedOrg: 333ef613-75bf-4e12-a4b1-8e3623f5dcea Content-Type: text/plain; charset="utf-8" By default, HPD was disabled on SN65DSI86 bridge. When the driver was added (commit "a095f15c00e27"), the HPD_DISABLE bit was set in pre-enable call which was moved to other function calls subsequently. Later on, commit "c312b0df3b13" added detect utility for DP mode. But with HPD_DISABLE bit set, all the HPD events are disabled[0] and the debounced state always return 1 (always connected state). Set HPD_DISABLE bit conditionally based on "no-hpd" property. Since the HPD_STATE is reflected correctly only after waiting for debounce time (~100-400ms) and adding this delay in detect() is not feasible owing to the performace impact (glitches and frame drop), remove runtime calls in detect() and add hpd_enable()/disable() bridge hooks with runtime calls, to detect hpd properly without any delay. [0]: (Pg. 32) Fixes: c312b0df3b13 ("drm/bridge: ti-sn65dsi86: Implement bridge connector = operations for DP") Cc: Max Krummenacher Signed-off-by: Jayesh Choudhary --- Changelog v2->v3: - Change conditional based on no-hpd property to address [1] - Remove runtime calls in detect() with appropriate comments - Add hpd_enable() and hpd_disable() in drm_bridge_funcs - Not picking up "Tested-by" tag as there are new changes v2 patch link: [1]: This would also require dts changes in all the nodes of sn65dsi86 to ensure that they have no-hpd property. drivers/gpu/drm/bridge/ti-sn65dsi86.c | 40 +++++++++++++++++++++++---- 1 file changed, 35 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi86.c b/drivers/gpu/drm/bridge= /ti-sn65dsi86.c index 60224f476e1d..e9ffc58acf58 100644 --- a/drivers/gpu/drm/bridge/ti-sn65dsi86.c +++ b/drivers/gpu/drm/bridge/ti-sn65dsi86.c @@ -190,6 +190,7 @@ struct ti_sn65dsi86 { u8 ln_assign; u8 ln_polrs; bool comms_enabled; + bool no_hpd; struct mutex comms_mutex; =20 #if defined(CONFIG_OF_GPIO) @@ -352,8 +353,10 @@ static void ti_sn65dsi86_enable_comms(struct ti_sn65ds= i86 *pdata, * change this to be conditional on someone specifying that HPD should * be used. */ - regmap_update_bits(pdata->regmap, SN_HPD_DISABLE_REG, HPD_DISABLE, - HPD_DISABLE); + + if (pdata->no_hpd) + regmap_update_bits(pdata->regmap, SN_HPD_DISABLE_REG, HPD_DISABLE, + HPD_DISABLE); =20 pdata->comms_enabled =3D true; =20 @@ -1195,9 +1198,17 @@ static enum drm_connector_status ti_sn_bridge_detect= (struct drm_bridge *bridge) struct ti_sn65dsi86 *pdata =3D bridge_to_ti_sn65dsi86(bridge); int val =3D 0; =20 - pm_runtime_get_sync(pdata->dev); + /* + * The chip won't report HPD right after being powered on as + * HPD_DEBOUNCED_STATE reflects correct state only after the + * debounce time (~100-400 ms). + * So having pm_runtime_get_sync() and immediately reading + * the register in detect() won't work, and adding delay() + * in detect will have performace impact in display. + * So remove runtime calls here. + */ + regmap_read(pdata->regmap, SN_HPD_DISABLE_REG, &val); - pm_runtime_put_autosuspend(pdata->dev); =20 return val & HPD_DEBOUNCED_STATE ? connector_status_connected : connector_status_disconnected; @@ -1220,6 +1231,20 @@ static void ti_sn65dsi86_debugfs_init(struct drm_bri= dge *bridge, struct dentry * debugfs_create_file("status", 0600, debugfs, pdata, &status_fops); } =20 +static void ti_sn_bridge_hpd_enable(struct drm_bridge *bridge) +{ + struct ti_sn65dsi86 *pdata =3D bridge_to_ti_sn65dsi86(bridge); + + pm_runtime_get_sync(pdata->dev); +} + +static void ti_sn_bridge_hpd_disable(struct drm_bridge *bridge) +{ + struct ti_sn65dsi86 *pdata =3D bridge_to_ti_sn65dsi86(bridge); + + pm_runtime_put_sync(pdata->dev); +} + static const struct drm_bridge_funcs ti_sn_bridge_funcs =3D { .attach =3D ti_sn_bridge_attach, .detach =3D ti_sn_bridge_detach, @@ -1234,6 +1259,8 @@ static const struct drm_bridge_funcs ti_sn_bridge_fun= cs =3D { .atomic_duplicate_state =3D drm_atomic_helper_bridge_duplicate_state, .atomic_destroy_state =3D drm_atomic_helper_bridge_destroy_state, .debugfs_init =3D ti_sn65dsi86_debugfs_init, + .hpd_enable =3D ti_sn_bridge_hpd_enable, + .hpd_disable =3D ti_sn_bridge_hpd_disable, }; =20 static void ti_sn_bridge_parse_lanes(struct ti_sn65dsi86 *pdata, @@ -1322,7 +1349,8 @@ static int ti_sn_bridge_probe(struct auxiliary_device= *adev, ? DRM_MODE_CONNECTOR_DisplayPort : DRM_MODE_CONNECTOR_eDP; =20 if (pdata->bridge.type =3D=3D DRM_MODE_CONNECTOR_DisplayPort) - pdata->bridge.ops =3D DRM_BRIDGE_OP_EDID | DRM_BRIDGE_OP_DETECT; + pdata->bridge.ops =3D DRM_BRIDGE_OP_EDID | DRM_BRIDGE_OP_DETECT | + DRM_BRIDGE_OP_HPD; =20 drm_bridge_add(&pdata->bridge); =20 @@ -1935,6 +1963,8 @@ static int ti_sn65dsi86_probe(struct i2c_client *clie= nt) return dev_err_probe(dev, PTR_ERR(pdata->refclk), "failed to get reference clock\n"); =20 + pdata->no_hpd =3D of_property_read_bool(dev->of_node, "no-hpd"); + pm_runtime_enable(dev); pm_runtime_set_autosuspend_delay(pdata->dev, 500); pm_runtime_use_autosuspend(pdata->dev); --=20 2.34.1