From nobody Wed Sep 17 13:55:34 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 51348C4332F for ; Mon, 19 Dec 2022 09:02:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231549AbiLSJC6 (ORCPT ); Mon, 19 Dec 2022 04:02:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36508 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229615AbiLSJCx (ORCPT ); Mon, 19 Dec 2022 04:02:53 -0500 Received: from mail-ed1-x532.google.com (mail-ed1-x532.google.com [IPv6:2a00:1450:4864:20::532]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5F7205FBD for ; Mon, 19 Dec 2022 01:02:51 -0800 (PST) Received: by mail-ed1-x532.google.com with SMTP id b69so11894662edf.6 for ; Mon, 19 Dec 2022 01:02:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20210112.gappssmtp.com; s=20210112; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=iaVNFQLQjvu/mR/33Qvn+CT5WA+rfSMQXLgBgZ4bdDM=; b=A1Zy6qoRVzqAGOFB96J1pF4ERIgoQXgHOFDmK4xgQnMA9IByu4kjh3dXqg9SDx0768 9eOIKZvrDVcu1Lr5SDz6I4UX/uAxyFhNWxM+FHxQkA2sCr6dltN3cwp60irQx8HJtWm7 1sGD1oV7eWyavHo4ijHytLcjchBuWv7EQj5AOSl3BmXFm10kcICy27AaZ+GL395V1wcD tRfxLexYrV9XfMDzIUGo6adh4OzxfZ9/V/EQJ+0QUZCnJ3A8IMvwPfAjiNdEh4Q7t6NK YxVD+9+UElauhoHi6RnNG91uqksaE0D+JEe1kGZBHjAFGJE/N3MFoTWOig+xWpIqZiXl c1SA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=iaVNFQLQjvu/mR/33Qvn+CT5WA+rfSMQXLgBgZ4bdDM=; b=CNvsHm7TKyR5diuAFlNnEgBPw6PYB0nAfRwLnHOMBlL/wD3VGfiMRf7x1GnXX2htb+ Ip7Z8YWhk8sruqQCwj4HnqJ86zDgrPI2z8vGgswQ3F9xKnEyFgijqqGnCo//8HTpBP1v KvUW4oWK3TkJX2uNr9OwpS2KJGGwmegIDM5ZIin5H508VR1+V0MOzbKA0nrmelH+KMlf gRHMI6WW+/oKdNjtTyjSiT1xKAF0+6AVtr24aXs7czokhaM45Ud4N8wMu7pfnze8uv0q 0AzxjDSiuN/oiEsM92NazkAIPCbmIXqtXiPP6EobwdlBHK5MxhG+yV0PrmHHxV3tBv/o wEug== X-Gm-Message-State: AFqh2krLLOXZ6bZ7b+iFMLBJjrXzRqHbzV30ul+0HIpH/WaLgZemhz64 pJV4OyVgVob/4QdELXahKJs8eSNMXrtGSq/k5fI= X-Google-Smtp-Source: AMrXdXvmKZdR1xqWjHm/Mr9GhLjb73U4gYdCZ+DsGSdF0LkhCf8Hqf8o1AVqcBklR1QtE2zrDB9YuA== X-Received: by 2002:a50:ed81:0:b0:477:ff25:867a with SMTP id h1-20020a50ed81000000b00477ff25867amr8453170edr.12.1671440569906; Mon, 19 Dec 2022 01:02:49 -0800 (PST) Received: from [127.0.1.1] ([2001:b07:5d39:f336:a0ba:cfa5:2107:c2c4]) by smtp.gmail.com with ESMTPSA id u11-20020a170906b10b00b00781dbdb292asm4082721ejy.155.2022.12.19.01.02.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 19 Dec 2022 01:02:49 -0800 (PST) From: Carlo Caione Date: Mon, 19 Dec 2022 10:02:37 +0100 Subject: [PATCH v4 1/2] drm/tiny: ili9486: Enable driver module autoloading MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20221116-s905x_spi_ili9486-v4-1-f86b4463b9e4@baylibre.com> References: <20221116-s905x_spi_ili9486-v4-0-f86b4463b9e4@baylibre.com> In-Reply-To: <20221116-s905x_spi_ili9486-v4-0-f86b4463b9e4@baylibre.com> To: Neil Armstrong , Kevin Hilman , Jerome Brunet , Mark Brown , Daniel Vetter , David Airlie , Kamlesh Gurudasani , Martin Blumenstingl Cc: dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, Carlo Caione , linux-kernel@vger.kernel.org, linux-amlogic@lists.infradead.org X-Mailer: b4 0.10.1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org SPI devices use the spi_device_id for module autoloading even on systems using device tree. Add the spi_device_id entry to enable autoloading for the 3.5inch RPi Display (rpi-lcd-35 and piscreen). Reviewed-by: Neil Armstrong Signed-off-by: Carlo Caione Reviewed-by: Thomas Zimmermann --- drivers/gpu/drm/tiny/ili9486.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/tiny/ili9486.c b/drivers/gpu/drm/tiny/ili9486.c index 1bb847466b10..8bf0dca0b05d 100644 --- a/drivers/gpu/drm/tiny/ili9486.c +++ b/drivers/gpu/drm/tiny/ili9486.c @@ -183,6 +183,8 @@ MODULE_DEVICE_TABLE(of, ili9486_of_match); =20 static const struct spi_device_id ili9486_id[] =3D { { "ili9486", 0 }, + { "rpi-lcd-35", 0 }, + { "piscreen", 0 }, { } }; MODULE_DEVICE_TABLE(spi, ili9486_id); --=20 b4 0.10.1 From nobody Wed Sep 17 13:55:34 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4ADF7C4332F for ; Mon, 19 Dec 2022 09:03:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231622AbiLSJDE (ORCPT ); Mon, 19 Dec 2022 04:03:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36510 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231579AbiLSJCx (ORCPT ); Mon, 19 Dec 2022 04:02:53 -0500 Received: from mail-ej1-x62b.google.com (mail-ej1-x62b.google.com [IPv6:2a00:1450:4864:20::62b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AA38E641F for ; Mon, 19 Dec 2022 01:02:52 -0800 (PST) Received: by mail-ej1-x62b.google.com with SMTP id n20so19971447ejh.0 for ; Mon, 19 Dec 2022 01:02:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20210112.gappssmtp.com; s=20210112; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=lqYmIYoxTMMpoYQgw16ovQhh+oEOozpYMDvGaahlUYc=; b=TQKO3zLxYXBYDTiW46AltPoen3RSbIyB8k2VaIuFnkph0BiNvBuGnifXGOY+zKrLEI LO5sFtmIdDq2PxEMYgnOvt2kONxeu0CuvZRF7RG/Gb6oTqzzUuJb9rGcEoDCqV3AfH8D qAURFDAeigb5FUW7znBFd1NHo9RBqP5xErBkXZNwvBgtXINDIsMZb8RgnpocJwD+jkf2 VUdQamL9R5duw9muX5u3+cYEnVdypu8N/js/a0YoywML0zu71Y0/HOQnRBi/T3dGWZ2F Bj5NawWiidI5fAUlI1sNlIVVeHkSlVpIpZHKEllff2+QyHvAPo0tSDNC02X/hcvuvfUF NETA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=lqYmIYoxTMMpoYQgw16ovQhh+oEOozpYMDvGaahlUYc=; b=pN+ohE1/GJR7am4ZrsdnQy/our8DCiu9kgpYn6IiIovKJzWUxToOKRDU/ftp6wADPj Fj5NRWfz4GsHF4oMo1WkzjNs68aPUYXg6KhjGLdUZlBj3/msB4gk3SRSPCs26GVExh3w HcOH7Cc76a1HUHLe0QGcPQXHkAiGIFgpaERGtkZXrCGLAzMge5PgXvhG4RVMlWlM0/PL JrbJm8FxOP6nsH/9rzQLN8JQTxCXPvG5Tx1+vD4H8zn4+CbTJn5eKOyCNtxBcCBguYyq Chcg3b8508ec/px2RxN6fSzyyanaq8b9gvuJpqdYGYogoVWhXt+Fd7zsb37x/6lZuWcg YaDA== X-Gm-Message-State: ANoB5pnXGb8/XGy2L9TdqwlCUV2dVlGF2nKc+3AgXabO70SyNzHJBo6y gThL8gkH9Ud63RuKFQQcwC2h/w== X-Google-Smtp-Source: AA0mqf4NSk7Yw/HcS1h8rMvyHtywLl/r5oAAdXCCDdnKAMEYPX1/1IxBA282Q7E2z2acv/RmzDLBFw== X-Received: by 2002:a17:907:910b:b0:7c1:1c5:c7cd with SMTP id p11-20020a170907910b00b007c101c5c7cdmr28846533ejq.5.1671440571173; Mon, 19 Dec 2022 01:02:51 -0800 (PST) Received: from [127.0.1.1] ([2001:b07:5d39:f336:a0ba:cfa5:2107:c2c4]) by smtp.gmail.com with ESMTPSA id u11-20020a170906b10b00b00781dbdb292asm4082721ejy.155.2022.12.19.01.02.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 19 Dec 2022 01:02:50 -0800 (PST) From: Carlo Caione Date: Mon, 19 Dec 2022 10:02:38 +0100 Subject: [PATCH v4 2/2] drm/tiny: ili9486: Do not assume 8-bit only SPI controllers MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20221116-s905x_spi_ili9486-v4-2-f86b4463b9e4@baylibre.com> References: <20221116-s905x_spi_ili9486-v4-0-f86b4463b9e4@baylibre.com> In-Reply-To: <20221116-s905x_spi_ili9486-v4-0-f86b4463b9e4@baylibre.com> To: Neil Armstrong , Kevin Hilman , Jerome Brunet , Mark Brown , Daniel Vetter , David Airlie , Kamlesh Gurudasani , Martin Blumenstingl Cc: dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, Carlo Caione , linux-kernel@vger.kernel.org, linux-amlogic@lists.infradead.org X-Mailer: b4 0.10.1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The pixel data for the ILI9486 is always 16-bits wide and it must be sent over the SPI bus. When the controller is only able to deal with 8-bit transfers, this 16-bits data needs to be swapped before the sending to account for the big endian bus, this is on the contrary not needed when the SPI controller already supports 16-bits transfers. The decision about swapping the pixel data or not is taken in the MIPI DBI code by probing the controller capabilities: if the controller only suppors 8-bit transfers the data is swapped, otherwise it is not. This swapping/non-swapping is relying on the assumption that when the controller does support 16-bit transactions then the data is sent unswapped in 16-bits-per-word over SPI. The problem with the ILI9486 driver is that it is forcing 8-bit transactions also for controllers supporting 16-bits, violating the assumption and corrupting the pixel data. Align the driver to what is done in the MIPI DBI code by adjusting the transfer size to the maximum allowed by the SPI controller. Reviewed-by: Neil Armstrong Signed-off-by: Carlo Caione --- drivers/gpu/drm/tiny/ili9486.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/tiny/ili9486.c b/drivers/gpu/drm/tiny/ili9486.c index 8bf0dca0b05d..6f03531175bd 100644 --- a/drivers/gpu/drm/tiny/ili9486.c +++ b/drivers/gpu/drm/tiny/ili9486.c @@ -43,6 +43,7 @@ static int waveshare_command(struct mipi_dbi *mipi, u8 *c= md, u8 *par, size_t num) { struct spi_device *spi =3D mipi->spi; + unsigned int bpw =3D 8; void *data =3D par; u32 speed_hz; int i, ret; @@ -56,8 +57,6 @@ static int waveshare_command(struct mipi_dbi *mipi, u8 *c= md, u8 *par, * The displays are Raspberry Pi HATs and connected to the 8-bit only * SPI controller, so 16-bit command and parameters need byte swapping * before being transferred as 8-bit on the big endian SPI bus. - * Pixel data bytes have already been swapped before this function is - * called. */ buf[0] =3D cpu_to_be16(*cmd); gpiod_set_value_cansleep(mipi->dc, 0); @@ -71,12 +70,18 @@ static int waveshare_command(struct mipi_dbi *mipi, u8 = *cmd, u8 *par, for (i =3D 0; i < num; i++) buf[i] =3D cpu_to_be16(par[i]); num *=3D 2; - speed_hz =3D mipi_dbi_spi_cmd_max_speed(spi, num); data =3D buf; } =20 + /* + * Check whether pixel data bytes needs to be swapped or not + */ + if (*cmd =3D=3D MIPI_DCS_WRITE_MEMORY_START && !mipi->swap_bytes) + bpw =3D 16; + gpiod_set_value_cansleep(mipi->dc, 1); - ret =3D mipi_dbi_spi_transfer(spi, speed_hz, 8, data, num); + speed_hz =3D mipi_dbi_spi_cmd_max_speed(spi, num); + ret =3D mipi_dbi_spi_transfer(spi, speed_hz, bpw, data, num); free: kfree(buf); =20 --=20 b4 0.10.1