From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E73BB8F5D for ; Sun, 16 Jul 2023 20:37:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5AE75C433C8; Sun, 16 Jul 2023 20:37:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1689539837; bh=6sI+5E3Tr18K6pGRWCmu0t2jg4B2ooFw+4mx2O9h4cc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nY+iRqtEAZveA9h0cSbcwFvC/APOeq0LUWl9GSB6jD/2I+aJmmpyXVaMnZa+ipwPm XplacHGXfRU9PWKoVH3k6nyF+XqmUbBR3g6UPtLfQkWS3dJgQsReIbb19sPy1/sw+K Bts+C8698BYe9AYn5chO8WeEvkZ4OXFJPwmZ2ss8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Francesco Dolcini , Robert Foss , Sasha Levin Subject: [PATCH 6.1 150/591] drm/bridge: tc358768: fix TCLK_ZEROCNT computation Date: Sun, 16 Jul 2023 21:44:49 +0200 Message-ID: <20230716194927.746929027@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230716194923.861634455@linuxfoundation.org> References: <20230716194923.861634455@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Francesco Dolcini [ Upstream commit f9cf811374f42fca31ac34aaf59ee2ae72b89879 ] Correct computation of TCLK_ZEROCNT register. This register must be set to a value that ensure that (TCLK-PREPARECNT + TCLK-ZERO) > 300ns with the actual value of (TCLK-PREPARECNT + TCLK-ZERO) being (1 to 2) + (TCLK_ZEROCNT + 1)) x HSByteClkCycle + (PHY output delay) with PHY output delay being about (2 to 3) x MIPIBitClk cycle in the BitClk conversion. Fixes: ff1ca6397b1d ("drm/bridge: Add tc358768 driver") Signed-off-by: Francesco Dolcini Reviewed-by: Robert Foss Signed-off-by: Robert Foss Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-5-francesco@dolcini.it Signed-off-by: Sasha Levin --- drivers/gpu/drm/bridge/tc358768.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c index 9bc726b79dd57..765bdebbd06f9 100644 --- a/drivers/gpu/drm/bridge/tc358768.c +++ b/drivers/gpu/drm/bridge/tc358768.c @@ -743,10 +743,10 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge) /* 38ns < TCLK_PREPARE < 95ns */ val = tc358768_ns_to_cnt(65, dsibclk_nsk) - 1; - /* TCLK_PREPARE > 300ns */ - val2 = tc358768_ns_to_cnt(300 + tc358768_to_ns(3 * ui_nsk), - dsibclk_nsk); - val |= (val2 - tc358768_to_ns(phy_delay_nsk - dsibclk_nsk)) << 8; + /* TCLK_PREPARE + TCLK_ZERO > 300ns */ + val2 = tc358768_ns_to_cnt(300 - tc358768_to_ns(2 * ui_nsk), + dsibclk_nsk) - 2; + val |= val2 << 8; dev_dbg(priv->dev, "TCLK_HEADERCNT: 0x%x\n", val); tc358768_write(priv, TC358768_TCLK_HEADERCNT, val); -- 2.39.2