From mboxrd@z Thu Jan 1 00:00:00 1970 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 300EDC433FE for ; Mon, 1 Nov 2021 06:27:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 09F8F61077 for ; Mon, 1 Nov 2021 06:27:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230096AbhKAGaB (ORCPT ); Mon, 1 Nov 2021 02:30:01 -0400 Received: from szxga02-in.huawei.com ([45.249.212.188]:15326 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229827AbhKAGaA (ORCPT ); Mon, 1 Nov 2021 02:30:00 -0400 Received: from dggeme755-chm.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4HjNNz6Fjtz90fs; Mon, 1 Nov 2021 14:27:15 +0800 (CST) Received: from huawei.com (10.67.174.47) by dggeme755-chm.china.huawei.com (10.3.19.101) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2308.15; Mon, 1 Nov 2021 14:27:23 +0800 From: He Ying To: , , , , CC: , , , Subject: [PATCH] drm: Grab reference of connector before return connector from sun4i_tcon_get_connector Date: Mon, 1 Nov 2021 02:29:06 -0400 Message-ID: <20211101062906.231518-1-heying24@huawei.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.67.174.47] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggeme755-chm.china.huawei.com (10.3.19.101) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >From the comments of drm_for_each_connector_iter(), we know that "connector is only valid within the list body, if you want to use connector after calling drm_connector_list_iter_end() then you need to grab your own reference first using drm_connector_get()". So fix the wrong use of connector according to the comments and then call drm_connector_put() after using connector finishes. Signed-off-by: He Ying --- drivers/gpu/drm/sun4i/sun4i_tcon.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c index 9f06dec0fc61..24fa6784ee5f 100644 --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c @@ -47,12 +47,12 @@ static struct drm_connector *sun4i_tcon_get_connector(const struct drm_encoder * drm_connector_list_iter_begin(encoder->dev, &iter); drm_for_each_connector_iter(connector, &iter) if (connector->encoder == encoder) { - drm_connector_list_iter_end(&iter); - return connector; + drm_connector_get(connector); + break; } drm_connector_list_iter_end(&iter); - return NULL; + return connector; } static int sun4i_tcon_get_pixel_depth(const struct drm_encoder *encoder) @@ -65,6 +65,7 @@ static int sun4i_tcon_get_pixel_depth(const struct drm_encoder *encoder) return -EINVAL; info = &connector->display_info; + drm_connector_put(connector); if (info->num_bus_formats != 1) return -EINVAL; @@ -361,6 +362,7 @@ static void sun4i_tcon0_mode_set_cpu(struct sun4i_tcon *tcon, /* TODO support normal CPU interface modes */ struct sun6i_dsi *dsi = encoder_to_sun6i_dsi(encoder); struct mipi_dsi_device *device = dsi->device; + struct drm_connector *connector; u8 bpp = mipi_dsi_pixel_format_to_bpp(device->format); u8 lanes = device->lanes; u32 block_space, start_delay; @@ -372,7 +374,9 @@ static void sun4i_tcon0_mode_set_cpu(struct sun4i_tcon *tcon, sun4i_tcon0_mode_set_common(tcon, mode); /* Set dithering if needed */ - sun4i_tcon0_mode_set_dithering(tcon, sun4i_tcon_get_connector(encoder)); + connector = sun4i_tcon_get_connector(encoder); + sun4i_tcon0_mode_set_dithering(tcon, connector); + drm_connector_put(connector); regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG, SUN4I_TCON0_CTL_IF_MASK, @@ -430,6 +434,7 @@ static void sun4i_tcon0_mode_set_lvds(struct sun4i_tcon *tcon, const struct drm_display_mode *mode) { unsigned int bp; + struct drm_connector *connector; u8 clk_delay; u32 reg, val = 0; @@ -440,7 +445,9 @@ static void sun4i_tcon0_mode_set_lvds(struct sun4i_tcon *tcon, sun4i_tcon0_mode_set_common(tcon, mode); /* Set dithering if needed */ - sun4i_tcon0_mode_set_dithering(tcon, sun4i_tcon_get_connector(encoder)); + connector = sun4i_tcon_get_connector(encoder); + sun4i_tcon0_mode_set_dithering(tcon, connector); + drm_connector_put(connector); /* Adjust clock delay */ clk_delay = sun4i_tcon_get_clk_delay(mode, 0); @@ -518,6 +525,7 @@ static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon, /* Set dithering if needed */ sun4i_tcon0_mode_set_dithering(tcon, connector); + drm_connector_put(connector); /* Adjust clock delay */ clk_delay = sun4i_tcon_get_clk_delay(mode, 0); -- 2.17.1