From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1cgTPN-0000uU-OX for barebox@lists.infradead.org; Wed, 22 Feb 2017 09:40:28 +0000 Date: Wed, 22 Feb 2017 10:40:01 +0100 From: Sascha Hauer Message-ID: <20170222094001.kjlneun4mpf2mgvk@pengutronix.de> References: <20170210073541.73bsfjhk3fu7nnwm@pengutronix.de> <20170215115104.qez5tgbsvwt3zxzz@pengutronix.de> <20170216072801.sh3byseyh3f6osgg@pengutronix.de> <067eac64-0c28-4012-23bb-813e462d74c2@eurekelettronica.it> <1487260229.13536.33.camel@pengutronix.de> <638491f2-9946-e9b1-e84e-e9ae05464bcc@eurekelettronica.it> <20170222080055.wkham5jaqbidfizl@pengutronix.de> <75ff7d5a-8952-590f-c6b4-9fc3d4c17753@eurekelettronica.it> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <75ff7d5a-8952-590f-c6b4-9fc3d4c17753@eurekelettronica.it> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: Using LVDS in a iMX6Q/D from Barebox To: gianluca Cc: barebox@lists.infradead.org On Wed, Feb 22, 2017 at 09:26:25AM +0100, gianluca wrote: > On 02/22/2017 09:00 AM, Sascha Hauer wrote: > > On Fri, Feb 17, 2017 at 04:38:37PM +0100, gianluca wrote: > > > On 02/16/2017 04:50 PM, Lucas Stach wrote: > > > > Am Donnerstag, den 16.02.2017, 15:43 +0100 schrieb gianluca: > > > > > On 02/16/2017 08:28 AM, Sascha Hauer wrote: > > > > > > On Wed, Feb 15, 2017 at 03:34:55PM +0100, gianluca wrote: > > > > > > > On 02/15/2017 12:51 PM, Sascha Hauer wrote: > > > > > > > > On Tue, Feb 14, 2017 at 11:32:44AM +0100, gianluca wrote: > > > > > > > > > On 02/10/2017 08:35 AM, Sascha Hauer wrote: > > > > > > > If no eeprom is found activate the status of the hdmi node from "disabled" > > > > > > > to "okay". So with the same algorithm as above, > > > > > > > > > > > > > > Those operations will be done in the coredevice_initcall() level. Is this > > > > > > > correct? > > > > > > > > > > > > Sounds like a plan. I'm not sure though if you find your EEPROM at > > > > > > coredevice_initcall time. > > > > > > > > > > > > > > > > Nope. Accessing device drivers (enabled in the device-tree) is possible > > > > > in the section: device_initcall() and *NOT* in the coredevice_initcall() > > > > > time. > > > > > > > > > > Anyway I was wondering if looking for a node in the device-tree, it will > > > > > be possible to change the status of that node. > > > > > > > > > > in DTS I have > > > > > > > > > > &hdmi { > > > > > status="disabled"; > > > > > } > > > > > > > > > > but I need to set the status to "okay" later on the device_initcall() time. > > > > > > > > > > Iterating in the device tree using for_each_node_by_name_from() does not > > > > > show any node like hdmi, but using the same function to look for any > > > > > "display-timing" section it works. > > > > > > > > The node isn't called just "hdmi", that is just the handle, which may > > > > not even be present in the final DTB if nothing uses it. The nodes name > > > > is "hdmi@0120000". > > > > > > > > See "arch/arm/boot/dts/imx6qdl.dtsi". > > > > > > > > > > Ok, thank you for hints. > > > > > > From my dts file: > > > > > > > &hdmi { > > > > ddc-i2c-bus = <&i2c2>; > > > > status = "disabled"; > > > > }; > > > > > > > > > > It is disabled by default. It will be enabled later by my device_initcall() > > > function. > > > > > > > &ldb { > > > > #address-cells = <1>; > > > > #size-cells = <0>; > > > > status = "disabled"; > > > > > > > > > > As the hdmi node. > > > > > > > lvds0: lvds-channel@0 { > > > > fsl,data-mapping = "spwg"; > > > > fsl,data-width = <24>; > > > > status = "disabled"; > > > > > > > > > > Just for sure it is disabled too! > > > > > > > > > > display-timings { > > > > native-mode = <&am128080n3tz>; > > > > > > This is fixed. It will be changed during the device_initcall() functions. > > > > > > > /* DISPLAY 1280x800 AMPIRE AM1280800N3TZ */ > > > > am128080n3tz: am1280800n3tz { > > > > clock-frequency = <71000000>; > > > > hactive = <1280>; > > > > vactive = <800>; > > > > hback-porch = <50>; > > > > hfront-porch = <50>; > > > > vback-porch = <5>; > > > > vfront-porch = <5>; > > > > hsync-len = <60>; > > > > vsync-len = <13>; > > > > hsync-active = <0>; > > > > vsync-active = <0>; > > > > de-active = <1>; > > > > pixelclk-active = <0>; > > > > }; > > > > /* DISPLAY 1024x600 AMPIRE AM-1024600LTM LVDS */ > > > > am1024600l: am1024600l { > > > > clock-frequency = <51200000>; > > > > hactive = <1024>; > > > > vactive = <600>; > > > > hback-porch = <0>; > > > > hfront-porch = <320>; > > > > vback-porch = <0>; > > > > vfront-porch = <35>; > > > > hsync-len = <1>; > > > > vsync-len = <1>; > > > > hsync-active = <0>; > > > > vsync-active = <0>; > > > > de-active = <1>; > > > > pixelclk-active = <0>; > > > > }; > > > > /* DISPLAY 800x480 */ > > > > ph800480t013: ph800480t013 { > > > > clock-frequency = <33300000>; > > > > hactive = <800>; > > > > vactive = <480>; > > > > hback-porch = <46>; > > > > hfront-porch = <210>; > > > > vback-porch = <23>; > > > > vfront-porch = <22>; > > > > hsync-len = <1>; > > > > vsync-len = <1>; > > > > hsync-active = <0>; > > > > vsync-active = <0>; > > > > de-active = <1>; > > > > pixelclk-active = <0>; > > > > }; > > > > }; > > > > > > > > port@4 { > > > > reg = <4>; > > > > lvds0_out: endpoint { > > > > remote-endpoint = <&in_lvds0>; > > > > }; > > > > }; > > > > > > > > }; > > > > }; > > > > > > The device_initcall() functions is looking for an eeprom on the lvds > > > channel, and if found it will matched against the native-mode phandle. > > > If it is different from the default, a new native-mode will be placed as > > > native-mode, and afterall the lvds-channel@0 and ldb will be flagged in > > > status as "okay". > > > > > > Then the of_device_enable_and_register_by_name("ldb@020e0008") will be > > > called. > > > > > > In the same way if an eeprom is found on the hdmi connector bus, the hdmi > > > status will be changed to "okay". > > > > > > If there is no display (so no eeprom either) connected on the lvds > > > connector, the device_initcall() functions will let all ldb stuff as default > > > (i.e. disabled) and it will enable the hdmi section if there is a hdmi > > > display (and its eeprom EDID) connected. > > > > > > The problem is the modeset of framebuffer (.num_modes): this list is created > > > from the device-tree sequence and the default does not respect the > > > native-mode section. i.e. if I have a 800x480 native mode display timing in > > > the device tree as a third option, the fb0.modes will have the 800x480 in > > > the third place. > > > > > > There is a quick (and dirty) way of calling the fb0.mode_name inside a > > > device_initcall()? > > > > You can do a setenv("fb0.mode_name", "800x480"); > > > > Yep. I supposed. But putting it inside a C code, need a recompilation. I > opted for calling explicity in the init script shell to do this kinda stuff. > > > However, it would be nicer to make the native mode the default. struct > > display_timings already has a native_mode field, but currently noone is > > interested in its value. > > > > Actually in my code I do: > > > static int of_display_timing_set(const char *name) > > { > > int ret = -1; > > struct device_node *root = NULL; > > struct device_node *display = NULL; > > struct device_node *timing = NULL; > > const char *node = "display-timings"; > > > > pr_debug("%s Enter with: ACTIVATING %s as NATIVE-MODE\n", __func__, name); > > > > root = of_get_root_node(); > > > > for_each_node_by_name_from(display, root, node) { > > if (display != NULL) { > > for_each_node_by_name_from(display, root, name) { > > timing = display; > > if (timing != NULL) { > > pr_debug("%s Node: %s PTR: 0x%p\n", > > __func__, timing->full_name, timing); > > break; > > } > > } > > } else { > > continue; > > } > > } > > > > if (name != NULL && timing != NULL) { > > pr_debug("%s Activating native-mode %s\n", __func__, name); > > /* > > * Now we have the correct phandle ptr for the correct timing > > * to point to. Now change the native-mode property to that phandle > > */ > > ret = of_set_property_to_child_phandle(timing, "native-mode"); > > if (ret) { > > pr_err("%s Error on setting native-mode to %s\n", __func__, name); > > } > > } else { > > pr_debug("%s Some ptr are NULL! name: %p -- timing: %p\n", > > __func__, name, timing); > > } > > pr_debug("%s Exit with: %d\n", __func__, ret); > > return ret; > > In this way I set as default native-mode the name of the timings passed to > the function. Is there something better? > > Anyway, now I am doing the same stuff for compatibile property of the panel, > because Linux wants to have a timing hardcoded in the panel-simple instead > of getting them from the timing section of the device-tree. > > This is a very lack of feature to me. But now, it is quicker to use the > bootloader to compile the correctness of the compatible property to a > almost-identical-timings found in the panel-simple.c... > > The other way is to add a edid chip (@ 0x50) for every panel I add, so to > let the EDID stuff to discover what is connected or not to the lvds board. > > This issue can not simply solved in this board, because I do have an > internal eeprom at address 0x50, but it can not be usable for EDID stuff. > > So I have two options: > > 1- let the imx-ldb.c code in the kernel to probe (simple-panel and edid) and > *add* a way to parse the device-tree for adding mode timing property using > the display-timing stuff. (this means kernel patch) And it's a patch you probably cannot upstream as for reasons I do not understand Thierry refuses to parse timings from the device tree. He insists on determing timings based on the compatible string. > > 2- look for a common timings from an existing displays in simple-panel.c and > pass them to the compatibile property of the panel in the device-tree via > bootloader. You should add the correct compatible and add support for it to the simple-panel driver. This also requires a kernel patch, but one you can upstream. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox