From patchwork Fri Aug 14 15:50:19 2015
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
X-Patchwork-Submitter: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
X-Patchwork-Id: 52449
Return-Path: <patchwork-forward+bncBC27VH7PV4DBBZM4XCXAKGQEO6UMRPI@linaro.org>
X-Original-To: linaro@patches.linaro.org
Delivered-To: linaro@patches.linaro.org
Received: from mail-wi0-f198.google.com (mail-wi0-f198.google.com
 [209.85.212.198])
 by patches.linaro.org (Postfix) with ESMTPS id 338AF2031F
 for <linaro@patches.linaro.org>; Fri, 14 Aug 2015 15:51:02 +0000 (UTC)
Received: by wilj18 with SMTP id j18sf7619640wil.0
 for <linaro@patches.linaro.org>; Fri, 14 Aug 2015 08:51:01 -0700 (PDT)
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
 d=1e100.net; s=20130820;
 h=x-gm-message-state:mime-version:delivered-to:from:to:cc:subject
 :date:message-id:in-reply-to:references:sender:precedence:list-id
 :x-original-sender:x-original-authentication-results:mailing-list
 :list-post:list-help:list-archive:list-unsubscribe;
 bh=ilNl1Ypce4nj+16wYoQ9KW0aiIN9qNDyoEXAkN/Zc+8=;
 b=fu7tCWbkvjvz+fW7KldCG18WBszTiOYXx+jUlrjCxTHdZg/VZYORHSjqfQimtX/oPs
 FKEIir5T0kektk8nHMFUz/5GoJBnpA+fqm8eCKKMAO3xYUI0CDZj7FHeCTHEK5wmQHIv
 PDXWKFLJTc8riPgcx4R1J7F7DcKM0GHLN4HkqPQDIjY3RfXeXQTRvQJeQBp4AeiT00S9
 l5iJUj9qBudTOHa34j49jcl2qD4aEduiIQc0Nce2J+abtkqCWvXEYijWlYi39Dii77CV
 1xB3GSMCU+QSovRWp4ilxeNsIqB2N+kxJe3/BoqsSbM4vtj5YPIkL7Yc/+/JfoPmgXin
 wf4A==
X-Gm-Message-State: ALoCoQnO6MOKXXbClNtBn2tRWjuEe+v91Cq5FxPP9d2lKgFQ/My+exLjiRIx+FEiB42IN/3Vnbz+
X-Received: by 10.113.3.8 with SMTP id bs8mr13217424lbd.23.1439567461532;
 Fri, 14 Aug 2015 08:51:01 -0700 (PDT)
MIME-Version: 1.0
X-BeenThere: patchwork-forward@linaro.org
Received: by 10.152.2.198 with SMTP id 6ls443598law.79.gmail;
 Fri, 14 Aug 2015 08:51:01 -0700 (PDT)
X-Received: by 10.112.105.104 with SMTP id gl8mr44680856lbb.81.1439567461085; 
 Fri, 14 Aug 2015 08:51:01 -0700 (PDT)
Received: from mail-la0-f47.google.com (mail-la0-f47.google.com.
 [209.85.215.47]) by mx.google.com with ESMTPS id
 qx9si6194435lbb.116.2015.08.14.08.51.01
 for <patchwork-forward@linaro.org>
 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128);
 Fri, 14 Aug 2015 08:51:01 -0700 (PDT)
Received-SPF: pass (google.com: domain of
 patch+caf_=patchwork-forward=linaro.org@linaro.org designates
 209.85.215.47 as permitted sender) client-ip=209.85.215.47; 
Received: by lalv9 with SMTP id v9so46268092lal.0
 for <patchwork-forward@linaro.org>;
 Fri, 14 Aug 2015 08:51:01 -0700 (PDT)
X-Received: by 10.112.219.70 with SMTP id pm6mr44189723lbc.41.1439567460972; 
 Fri, 14 Aug 2015 08:51:00 -0700 (PDT)
X-Forwarded-To: patchwork-forward@linaro.org
X-Forwarded-For: patch@linaro.org patchwork-forward@linaro.org
Delivered-To: patch@linaro.org
Received: by 10.112.7.198 with SMTP id l6csp1715581lba;
 Fri, 14 Aug 2015 08:50:59 -0700 (PDT)
X-Received: by 10.66.243.70 with SMTP id ww6mr90456642pac.88.1439567459539; 
 Fri, 14 Aug 2015 08:50:59 -0700 (PDT)
Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67])
 by mx.google.com with ESMTP id dk5si9626155pbc.22.2015.08.14.08.50.58;
 Fri, 14 Aug 2015 08:50:59 -0700 (PDT)
Received-SPF: pass (google.com: best guess record for domain of
 linux-kernel-owner@vger.kernel.org designates 209.132.180.67
 as permitted sender) client-ip=209.132.180.67; 
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
 id S1755568AbbHNPuz (ORCPT <rfc822;matthew.hart@linaro.org>
 + 28 others); Fri, 14 Aug 2015 11:50:55 -0400
Received: from mail-wi0-f181.google.com ([209.85.212.181]:38069 "EHLO
 mail-wi0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
 with ESMTP id S1755534AbbHNPuw (ORCPT
 <rfc822;linux-kernel@vger.kernel.org>);
 Fri, 14 Aug 2015 11:50:52 -0400
Received: by wicja10 with SMTP id ja10so25182778wic.1
 for <linux-kernel@vger.kernel.org>;
 Fri, 14 Aug 2015 08:50:51 -0700 (PDT)
X-Received: by 10.181.11.168 with SMTP id ej8mr8216114wid.83.1439567451499; 
 Fri, 14 Aug 2015 08:50:51 -0700 (PDT)
Received: from localhost.localdomain (host-92-13-246-184.as43234.net.
 [92.13.246.184]) by smtp.gmail.com with ESMTPSA id
 k2sm3682141wif.4.2015.08.14.08.50.46
 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA bits=128/128);
 Fri, 14 Aug 2015 08:50:51 -0700 (PDT)
From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
To: Thierry Reding <thierry.reding@gmail.com>, dri-devel@lists.freedesktop.org
Cc: David Airlie <airlied@linux.ie>, linux-kernel@vger.kernel.org,
 linux-arm-msm@vger.kernel.org, robdclark@gmail.com, bjorn@kryo.se,
 Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Subject: [PATCH RFC 3/5] drm/panel: simple-panel: Add panel picker support.
Date: Fri, 14 Aug 2015 16:50:19 +0100
Message-Id: <1439567419-13721-1-git-send-email-srinivas.kandagatla@linaro.org>
X-Mailer: git-send-email 1.9.1
In-Reply-To: <439567280-13491-1-git-send-email-srinivas.kandagatla@linaro.org>
References: <439567280-13491-1-git-send-email-srinivas.kandagatla@linaro.org>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: list
List-ID: <patchwork-forward.linaro.org>
X-Mailing-List: linux-kernel@vger.kernel.org
X-Removed-Original-Auth: Dkim didn't pass.
X-Original-Sender: srinivas.kandagatla@linaro.org
X-Original-Authentication-Results: mx.google.com; spf=pass (google.com:
 domain of
 patch+caf_=patchwork-forward=linaro.org@linaro.org designates
 209.85.215.47 as permitted sender)
 smtp.mailfrom=patch+caf_=patchwork-forward=linaro.org@linaro.org
Mailing-list: list patchwork-forward@linaro.org;
 contact patchwork-forward+owners@linaro.org
X-Google-Group-Id: 836684582541
List-Post: <http://groups.google.com/a/linaro.org/group/patchwork-forward/post>, 
 <mailto:patchwork-forward@linaro.org>
List-Help: <http://support.google.com/a/linaro.org/bin/topic.py?topic=25838>, 
 <mailto:patchwork-forward+help@linaro.org>
List-Archive: <http://groups.google.com/a/linaro.org/group/patchwork-forward/>
List-Unsubscribe: <mailto:googlegroups-manage+836684582541+unsubscribe@googlegroups.com>, 
 <http://groups.google.com/a/linaro.org/group/patchwork-forward/subscribe>

This patch adds panel picker support to simple-panel.

The idea of panel picker is to select the correct panel timings if it
supports probing edid via DDC bus, edid contains manufacture ID
and Manufacturer product code, so it can match against the panel_picker
entries to get the correct panel timings.

>From DT point of view the panel picker uses generic compatible string
"panel-simple", keeping the panel specific compatible strings still
supported.

Panels can be static entry in the DT, but practically development boards
like IFC6410 where developers can connect any LVDS panel which makes it
difficult to maintian the dt support for those panels in dts file.
With this dynamic probing via panel picker makes it easy to support such
use-cases.
This patch also adds panel presence detection based, if there is no
panel detected or panel picker could not find the panel then the driver
would mark the panel DT node as disabled so that the drm driver would
be able to take right decision based on that panel node status.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/gpu/drm/panel/panel-simple.c | 83 +++++++++++++++++++++++++++++++++++-
 1 file changed, 81 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
index f94201b..6c503b2 100644
--- a/drivers/gpu/drm/panel/panel-simple.c
+++ b/drivers/gpu/drm/panel/panel-simple.c
@@ -32,6 +32,7 @@
 #include <drm/drm_crtc.h>
 #include <drm/drm_mipi_dsi.h>
 #include <drm/drm_panel.h>
+#include <drm/drm_edid.h>
 
 #include <video/display_timing.h>
 #include <video/videomode.h>
@@ -70,6 +71,18 @@ struct panel_desc {
 	u32 bus_format;
 };
 
+#define PANEL_PICKER_ENTRY(vend, pid, pdesc) \
+		.vendor = vend, \
+		.product_id = (pid), \
+		.data = (pdesc)
+
+/* Panel picker entry with vendor and product id */
+struct panel_picker_entry {
+	char vendor[4]; /* Vendor string */
+	int product_id; /* product id field */
+	const struct panel_desc *data;
+};
+
 struct panel_simple {
 	struct drm_panel base;
 	bool prepared;
@@ -84,6 +97,8 @@ struct panel_simple {
 	struct gpio_desc *enable_gpio;
 };
 
+static const struct panel_desc *panel_picker_find_panel(struct edid *edid);
+
 static inline struct panel_simple *to_panel_simple(struct drm_panel *panel)
 {
 	return container_of(panel, struct panel_simple, base);
@@ -276,11 +291,28 @@ static const struct drm_panel_funcs panel_simple_funcs = {
 	.get_timings = panel_simple_get_timings,
 };
 
+static void __init simple_panel_node_disable(struct device_node *node)
+{
+	struct property *prop;
+
+	prop = kzalloc(sizeof(*prop), GFP_KERNEL);
+	if (!prop)
+		return;
+
+	prop->name = "status";
+	prop->value = "disabled";
+	prop->length = strlen((char *)prop->value)+1;
+
+	of_update_property(node, prop);
+}
+
+
 static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
 {
 	struct device_node *backlight, *ddc;
 	struct panel_simple *panel;
 	int err;
+	struct edid *edid;
 
 	panel = devm_kzalloc(dev, sizeof(*panel), GFP_KERNEL);
 	if (!panel)
@@ -288,7 +320,6 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
 
 	panel->enabled = false;
 	panel->prepared = false;
-	panel->desc = desc;
 
 	panel->supply = devm_regulator_get(dev, "power");
 	if (IS_ERR(panel->supply))
@@ -316,7 +347,25 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
 		panel->ddc = of_find_i2c_adapter_by_node(ddc);
 		of_node_put(ddc);
 
-		if (!panel->ddc) {
+		if (panel->ddc) {
+			/* detect panel presence */
+			if (!drm_probe_ddc(panel->ddc)) {
+				err = -ENODEV;
+				goto nodev;
+			}
+
+			/* get panel from edid */
+			if (of_device_is_compatible(dev->of_node,
+						"panel-simple")) {
+				edid = drm_get_edid_early(panel->ddc);
+				if (edid) {
+					desc = panel_picker_find_panel(edid);
+				} else {
+					err = -ENODEV;
+					goto nodev;
+				}
+			}
+		} else {
 			err = -EPROBE_DEFER;
 			goto free_backlight;
 		}
@@ -325,6 +374,7 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
 	drm_panel_init(&panel->base);
 	panel->base.dev = dev;
 	panel->base.funcs = &panel_simple_funcs;
+	panel->desc = desc;
 
 	err = drm_panel_add(&panel->base);
 	if (err < 0)
@@ -334,6 +384,10 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
 
 	return 0;
 
+nodev:
+	/* mark the dt as disabled */
+	simple_panel_node_disable(dev->of_node);
+
 free_ddc:
 	if (panel->ddc)
 		put_device(&panel->ddc->dev);
@@ -1036,6 +1090,10 @@ static const struct panel_desc shelly_sca07010_bfn_lnn = {
 	.bus_format = MEDIA_BUS_FMT_RGB666_1X18,
 };
 
+static const struct panel_picker_entry panel_picker_list[] = {
+	{ PANEL_PICKER_ENTRY("AUO", 0x10dc, &auo_b101xtn01) },
+};
+
 static const struct of_device_id platform_of_match[] = {
 	{
 		.compatible = "ampire,am800480r3tmqwa1h",
@@ -1125,11 +1183,32 @@ static const struct of_device_id platform_of_match[] = {
 		.compatible = "shelly,sca07010-bfn-lnn",
 		.data = &shelly_sca07010_bfn_lnn,
 	}, {
+		/* Panel Picker Vendor ID and Product ID based Lookup */
+		.compatible = "panel-simple",
+	}, {
 		/* sentinel */
 	}
 };
 MODULE_DEVICE_TABLE(of, platform_of_match);
 
+static const struct panel_desc *panel_picker_find_panel(struct edid *edid)
+{
+	int i;
+	const struct panel_desc *desc = NULL;
+
+	for (i = 0; i < ARRAY_SIZE(panel_picker_list); i++) {
+		const struct panel_picker_entry *vp = &panel_picker_list[i];
+
+		if (edid_vendor(edid, (char *)vp->vendor) &&
+				(EDID_PRODUCT_ID(edid) == vp->product_id)) {
+			desc = vp->data;
+			break;
+		}
+	}
+
+	return desc;
+}
+
 static int panel_simple_platform_probe(struct platform_device *pdev)
 {
 	const struct of_device_id *id;