From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sylwester Nawrocki Subject: Re: [PATCH v4 5/5] ARM: exynos: dts: Add FIMD DT binding Documentation Date: Mon, 18 Feb 2013 22:46:01 +0100 Message-ID: <5122A119.7070501@gmail.com> References: <1360912200-26377-1-git-send-email-vikas.sajjan@linaro.org> <1360912200-26377-6-git-send-email-vikas.sajjan@linaro.org> <511E1008.6010308@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ee0-f42.google.com ([74.125.83.42]:50719 "EHLO mail-ee0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756380Ab3BRVqG (ORCPT ); Mon, 18 Feb 2013 16:46:06 -0500 Received: by mail-ee0-f42.google.com with SMTP id b47so3169883eek.1 for ; Mon, 18 Feb 2013 13:46:04 -0800 (PST) In-Reply-To: Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: Vikas Sajjan Cc: Sylwester Nawrocki , linux-samsung-soc@vger.kernel.org, kgene.kim@samsung.com, sachin.kamat@linaro.org, sunil joshi , Inki Dae Hi, On 02/18/2013 11:51 AM, Vikas Sajjan wrote: > On 15 February 2013 16:08, Sylwester Nawrocki wrote: >> On 02/15/2013 08:10 AM, Vikas Sajjan wrote: >>> Adds FIMD DT binding documentation both SoC and Board, with an example >>> >>> Signed-off-by: Vikas Sajjan >>> --- >>> .../devicetree/bindings/drm/exynos/fimd.txt | 37 ++++++++++++++++++++ >>> 1 file changed, 37 insertions(+) >>> create mode 100644 Documentation/devicetree/bindings/drm/exynos/fimd.txt >>> >>> diff --git a/Documentation/devicetree/bindings/drm/exynos/fimd.txt b/Documentation/devicetree/bindings/drm/exynos/fimd.txt >>> new file mode 100644 >>> index 0000000..bec9d07 >>> --- /dev/null >>> +++ b/Documentation/devicetree/bindings/drm/exynos/fimd.txt Wouldn't Documentation/devicetree/bindings/video/exynos-fimd.txt be more appropriate location for this file ? There is also framebuffer driver for FIMD. Even if the framebuffer driver gets phased out it still feels like a more intuitive location for a display controller bindings. This is just my humble suggestion though. I think you should CC the device tree mailing list and the maintainers. >>> @@ -0,0 +1,37 @@ >>> +Device-Tree bindings for fimd driver >>> + >>> +FIMD stands for Fully Interactive Mobile Display, is the Display Controller for >>> +the Exynos series of SoCs which transfers the image data from a video buffer >>> +located in the system memory to an external LCD interface. >>> + >>> +Required properties: >>> +- compatible := value should be "samsung,exynos5-fimd" or "samsung,exynos4-fimd" >> >> What about older SoCs like S5Pv210 ? There is the FIMD IP block in those SoCs >> as well. There are also differences in the FIMD IP block across various SoC >> version, so either you need to list the quirks in the bindings or use an >> appropriate compatible properties if there are significant differences across >> FIMDs that make them not really compatible. >> > as of now, I was working on Exynos4 and Exynos5 SoC. have to really > see the differences in the previous SoC and how to handle all those > FIMD IPs in the driver. > if you know the differences between these FIMD IPs, please let me know. Please have a look at drivers/video/s3c-fb.c and all driver_data structures defined for various SoCs. [...] > we have 3 interrupts and the Interrupt combiner order is FIFO Level , > VSYNC and LCD_SYSTEM. > since we only use VSYNC interrupt , In the driver to get the interrupt number > > res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); > if (!res) { > dev_err(dev, "irq request failed.\n"); > return -ENXIO; > } > > ctx->irq = res->start; > > I am passing the 3rd parameter as '0' , to get the VSYNC interrupt, > and hence in the DTSI file i have it in the order VSYNC, FIFO > LEVEL and LCD_SYSTEM. Yes, I'm aware what's going on here. Since I had to change the interrupts order when I used one of the first version of patches adding device tree support for FIMD, when I needed working display to test the camera. > what I can do is the pass the 3rd parameter as '1' , and rectify the > order in DTSI file as FIFO LEVEL, VSYNC and LCD_SYSTEM. Then you would have to do it only for dt case. I guess it is okay to require VSYNC as the first interrupt. I'm fine with that, as long as it is properly documented. -- Regards, Sylwester