From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 7DCFC3A1A3F; Sat, 17 Oct 2026 17:38:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792258707; cv=none; b=PKgRcqVZUYc2dmF63rsQSpWUogwf6FxEGcHx9lRO6zDZcP7AsgaUmEl8jRuxDVhHuyDOjojvfOaJUJwc0NuVa/f4QPx1i/lMbmVkkIT8YzG1UB4B2I2D5sj7ANR0cI1p/mAoDfsFnHFGrhFcLg/N+jPPX6axzb6MnVT4wBgt0nI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792258707; c=relaxed/simple; bh=tKb8QX+q/9wLvWn4jUyJA9gnt83FLckKohBV5PjhVOI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ZT54aNOzoVgBSpWPgtgtqktu+uo4oe0duX8EOicbCtjAcixLGslaOHdoPHVmghPP62ZYgGyiVJaGdtyJmatTPXj1hgZ2YuAmi9spwCpAzHDOCL+1uK17s2Rpj6+UKf5H9BsHOcRdpF1xX2Na6csjLhfRC4/X8Kpis/f2GH687w4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=E4nlXbxD; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="E4nlXbxD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C00D11F000C4; Sat, 17 Oct 2026 17:38:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1792258706; bh=ZbNW8wn7RtVNCki1und063tTATQKGA7AZlkKkj0+ovk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=E4nlXbxDPl+JMGpRlgw56IrSrIdF/vw+IP5rwdSaJF4RogIFFICXEmxGDTOHQlNsu O0m6u0/ZrdgizO1oN/aLBQCWRb7IZUTlAAeRYZNH0FlSA0N7kuwlSzjuY4dBcwGmC5 dAnnQdkocmlzjp1xZTLStb0B14CKz5ErcI1BNUho= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Biju Das , Hugo Villeneuve , Sasha Levin Subject: [PATCH 6.6 0932/1674] drm: renesas: rz-du: mipi_dsi: fix kernel panic when rebooting for some panels Date: Sat, 17 Oct 2026 17:53:24 +0200 Message-ID: <20261017160455.056731195@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261017160431.119607952@linuxfoundation.org> References: <20261017160431.119607952@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hugo Villeneuve [ Upstream commit 64aa8b3a60a825134f7d866adf05c024bbe0c24c ] Since commit 56de5e305d4b ("clk: renesas: r9a07g044: Add MSTOP for RZ/G2L") we may get the following kernel panic, for some panels, when rebooting: systemd-shutdown[1]: Rebooting. Call trace: ... do_serror+0x28/0x68 el1h_64_error_handler+0x34/0x50 el1h_64_error+0x6c/0x70 rzg2l_mipi_dsi_host_transfer+0x114/0x458 (P) mipi_dsi_device_transfer+0x44/0x58 mipi_dsi_dcs_set_display_off_multi+0x9c/0xc4 ili9881c_unprepare+0x38/0x88 drm_panel_unprepare+0xbc/0x108 This happens for panels that need to send MIPI-DSI commands in their unprepare() callback. Since the MIPI-DSI interface is stopped at that point, rzg2l_mipi_dsi_host_transfer() triggers the kernel panic. Fix by moving rzg2l_mipi_dsi_stop() to new callback function rzg2l_mipi_dsi_atomic_post_disable(). With this change we now have the correct power-down/stop sequence: systemd-shutdown[1]: Rebooting. rzg2l-mipi-dsi 10850000.dsi: rzg2l_mipi_dsi_atomic_disable(): entry ili9881c-dsi 10850000.dsi.0: ili9881c_unprepare(): entry rzg2l-mipi-dsi 10850000.dsi: rzg2l_mipi_dsi_atomic_post_disable(): entry reboot: Restarting system Suggested-by: Biju Das Signed-off-by: Hugo Villeneuve Tested-by: Biju Das Link: https://patch.msgid.link/20260112154333.655352-1-hugo@hugovil.com Signed-off-by: Biju Das Signed-off-by: Sasha Levin --- drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c index a9216a99b2be1..5b8da2b6cbd0f 100644 --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c @@ -574,6 +574,13 @@ static void rzg2l_mipi_dsi_atomic_disable(struct drm_bridge *bridge, rzg2l_mipi_dsi_stop_video(dsi); rzg2l_mipi_dsi_stop_hs_clock(dsi); +} + +static void rzg2l_mipi_dsi_atomic_post_disable(struct drm_bridge *bridge, + struct drm_bridge_state *old_bridge_state) +{ + struct rzg2l_mipi_dsi *dsi = bridge_to_rzg2l_mipi_dsi(bridge); + rzg2l_mipi_dsi_stop(dsi); } @@ -598,6 +605,7 @@ static const struct drm_bridge_funcs rzg2l_mipi_dsi_bridge_ops = { .atomic_reset = drm_atomic_helper_bridge_reset, .atomic_enable = rzg2l_mipi_dsi_atomic_enable, .atomic_disable = rzg2l_mipi_dsi_atomic_disable, + .atomic_post_disable = rzg2l_mipi_dsi_atomic_post_disable, .mode_valid = rzg2l_mipi_dsi_bridge_mode_valid, }; -- 2.53.0