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 5A91C27F07 for ; Fri, 21 Jul 2023 18:57:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CC547C433C7; Fri, 21 Jul 2023 18:57:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1689965839; bh=itfjXB6bJ+eAB1GZLd5QP1rtL/qXUvzlBpRTluypBeY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0NN2kakuSWme6DcpxwULRJRnOyzUFJvFDmNlmckBKZsnXyRfqK5/dcLZun4oy2yhC C07UdZzZNIvf6Si7i2QcJCKmoqpoPY4ZCx4lGgof6W2j1iFaT1Y7fi2SkYhps4BLWi Y0MfaFKI89UCdsR2yRHstOK0zt1dD23ShsK4U4FI= 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 5.15 104/532] drm/bridge: tc358768: fix TCLK_TRAILCNT computation Date: Fri, 21 Jul 2023 18:00:08 +0200 Message-ID: <20230721160620.212445321@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230721160614.695323302@linuxfoundation.org> References: <20230721160614.695323302@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 ee18698e212b1659dd0850d7e2ae0f22e16ed3d3 ] Correct computation of TCLK_TRAILCNT register. The driver does not implement non-continuous clock mode, so the actual value doesn't make a practical difference yet. However this change also ensures that the value does not write to reserved registers bits in case of under/overflow. This register must be set to a value that ensures that TCLK-TRAIL > 60ns and TEOT <= (105 ns + 12 x UI) with the actual value of TCLK-TRAIL being (TCLK_TRAILCNT + (1 to 2)) xHSByteClkCycle + (2 + (1 to 2)) * 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/20230427142934.55435-2-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-3-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-4-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-5-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-2-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-3-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-4-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-5-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-2-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-3-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-4-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-5-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-2-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-3-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-4-francesco@dolcini.it 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, 5 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c index 6e95dd4b7aef7..de4022c864034 100644 --- a/drivers/gpu/drm/bridge/tc358768.c +++ b/drivers/gpu/drm/bridge/tc358768.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -633,6 +634,7 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge) struct tc358768_priv *priv = bridge_to_tc358768(bridge); struct mipi_dsi_device *dsi_dev = priv->output.dev; u32 val, val2, lptxcnt, hact, data_type; + s32 raw_val; const struct drm_display_mode *mode; u32 dsibclk_nsk, dsiclk_nsk, ui_nsk, phy_delay_nsk; u32 dsiclk, dsibclk; @@ -733,9 +735,9 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge) dev_dbg(priv->dev, "TCLK_HEADERCNT: 0x%x\n", val); tc358768_write(priv, TC358768_TCLK_HEADERCNT, val); - /* TCLK_TRAIL > 60ns + 3*UI */ - val = 60 + tc358768_to_ns(3 * ui_nsk); - val = tc358768_ns_to_cnt(val, dsibclk_nsk) - 5; + /* TCLK_TRAIL > 60ns AND TEOT <= 105 ns + 12*UI */ + raw_val = tc358768_ns_to_cnt(60 + tc358768_to_ns(2 * ui_nsk), dsibclk_nsk) - 5; + val = clamp(raw_val, 0, 127); dev_dbg(priv->dev, "TCLK_TRAILCNT: 0x%x\n", val); tc358768_write(priv, TC358768_TCLK_TRAILCNT, val); -- 2.39.2