From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932921AbdJaTdS (ORCPT ); Tue, 31 Oct 2017 15:33:18 -0400 Received: from anholt.net ([50.246.234.109]:39880 "EHLO anholt.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932674AbdJaTdB (ORCPT ); Tue, 31 Oct 2017 15:33:01 -0400 From: Eric Anholt To: dri-devel@lists.freedesktop.org, Thierry Reding Cc: linux-kernel@vger.kernel.org, Eric Anholt Subject: [PATCH 2/2] drm/panel: Enable DSI transactions on the RPi panel. Date: Tue, 31 Oct 2017 12:32:58 -0700 Message-Id: <20171031193258.17373-2-eric@anholt.net> X-Mailer: git-send-email 2.15.0 In-Reply-To: <20171031193258.17373-1-eric@anholt.net> References: <20171031193258.17373-1-eric@anholt.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org It turns out that I had just mistaken what type of write the register writes were supposed to be, using DCS instead of generic long writes. Switching to transactions instead of using the atmel as a bridge also seems to resolve the sparkling pixels problem I've had. Signed-off-by: Eric Anholt Fixes: 2f733d6194bd ("drm/panel: Add support for the Raspberry Pi 7" Touchscreen.") --- drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c | 14 +------------- 1 file changed, 1 insertion(+), 13 deletions(-) diff --git a/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c b/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c index d964d454e4ae..2c9c9722734f 100644 --- a/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c +++ b/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c @@ -238,12 +238,6 @@ static void rpi_touchscreen_i2c_write(struct rpi_touchscreen *ts, static int rpi_touchscreen_write(struct rpi_touchscreen *ts, u16 reg, u32 val) { -#if 0 - /* The firmware uses LP DSI transactions like this to bring up - * the hardware, which should be faster than using I2C to then - * pass to the Toshiba. However, I was unable to get it to - * work. - */ u8 msg[] = { reg, reg >> 8, @@ -253,13 +247,7 @@ static int rpi_touchscreen_write(struct rpi_touchscreen *ts, u16 reg, u32 val) val >> 24, }; - mipi_dsi_dcs_write_buffer(ts->dsi, msg, sizeof(msg)); -#else - rpi_touchscreen_i2c_write(ts, REG_WR_ADDRH, reg >> 8); - rpi_touchscreen_i2c_write(ts, REG_WR_ADDRL, reg); - rpi_touchscreen_i2c_write(ts, REG_WRITEH, val >> 8); - rpi_touchscreen_i2c_write(ts, REG_WRITEL, val); -#endif + mipi_dsi_generic_write(ts->dsi, msg, sizeof(msg)); return 0; } -- 2.15.0