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 X-Spam-Level: X-Spam-Status: No, score=-16.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E143BC433E0 for ; Mon, 8 Feb 2021 23:41:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AF41E64E77 for ; Mon, 8 Feb 2021 23:41:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231549AbhBHXlG (ORCPT ); Mon, 8 Feb 2021 18:41:06 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:27738 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230154AbhBHXkt (ORCPT ); Mon, 8 Feb 2021 18:40:49 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612827561; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=FtKMf203CyAECItGmDPAFD2qpM0diNwtTxJLIdWBviE=; b=T4qcrN0iwM23EsR6LKpk8ftDjlbGvem7jJS8quYXvlOmfvb4q20yozVo+B7/pNGPRJ+e5f jUETg1dnSA0+J9ZkRmDHuH7imsX6v/HsKYfUjfl7TbsQycTXBuas2hrh+M+yA1cNJCqIOi w3l6bJV8pylpPtDPjhOYtv+OwBe10HA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-209-MtqmNM38MkmfgtwkZEClhQ-1; Mon, 08 Feb 2021 18:39:20 -0500 X-MC-Unique: MtqmNM38MkmfgtwkZEClhQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5A97E1935780; Mon, 8 Feb 2021 23:39:18 +0000 (UTC) Received: from Whitewolf.redhat.com (ovpn-114-219.rdu2.redhat.com [10.10.114.219]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4F25160938; Mon, 8 Feb 2021 23:39:17 +0000 (UTC) From: Lyude Paul To: dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Cc: Rodrigo Vivi , Jani Nikula , Joonas Lahtinen , David Airlie , Daniel Vetter , Sean Paul , linux-kernel@vger.kernel.org (open list) Subject: [RFC v4 04/11] drm/i915/dpcd_bl: Handle drm_dpcd_read/write() return values correctly Date: Mon, 8 Feb 2021 18:38:54 -0500 Message-Id: <20210208233902.1289693-5-lyude@redhat.com> In-Reply-To: <20210208233902.1289693-1-lyude@redhat.com> References: <20210208233902.1289693-1-lyude@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is kind of an annoying aspect of DRM's DP helpers: drm_dp_dpcd_readb/writeb() return the size of bytes read/written on success, thus we want to check against that instead of checking if the return value is less than 0. I'll probably be fixing this in the near future once I start doing DP work again, also because I'd rather not mix a tree-wide refactor like that in with a patch series intended to be around introducing DP backlight helpers. So, for now let's just handle the return values from each function correctly. Signed-off-by: Lyude Paul Reviewed-by: Rodrigo Vivi --- .../drm/i915/display/intel_dp_aux_backlight.c | 41 +++++++++---------- 1 file changed, 19 insertions(+), 22 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c index 62294967f430..c37ccc8538cb 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c @@ -107,7 +107,7 @@ intel_dp_aux_supports_hdr_backlight(struct intel_connector *connector) u8 tcon_cap[4]; ret = drm_dp_dpcd_read(aux, INTEL_EDP_HDR_TCON_CAP0, tcon_cap, sizeof(tcon_cap)); - if (ret < 0) + if (ret != sizeof(tcon_cap)) return false; if (!(tcon_cap[1] & INTEL_EDP_HDR_TCON_BRIGHTNESS_NITS_CAP)) @@ -137,7 +137,7 @@ intel_dp_aux_hdr_get_backlight(struct intel_connector *connector, enum pipe pipe u8 tmp; u8 buf[2] = { 0 }; - if (drm_dp_dpcd_readb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, &tmp) < 0) { + if (drm_dp_dpcd_readb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, &tmp) != 1) { drm_err(&i915->drm, "Failed to read current backlight mode from DPCD\n"); return 0; } @@ -153,7 +153,8 @@ intel_dp_aux_hdr_get_backlight(struct intel_connector *connector, enum pipe pipe return panel->backlight.max; } - if (drm_dp_dpcd_read(&intel_dp->aux, INTEL_EDP_BRIGHTNESS_NITS_LSB, buf, sizeof(buf)) < 0) { + if (drm_dp_dpcd_read(&intel_dp->aux, INTEL_EDP_BRIGHTNESS_NITS_LSB, buf, + sizeof(buf)) != sizeof(buf)) { drm_err(&i915->drm, "Failed to read brightness from DPCD\n"); return 0; } @@ -172,7 +173,8 @@ intel_dp_aux_hdr_set_aux_backlight(const struct drm_connector_state *conn_state, buf[0] = level & 0xFF; buf[1] = (level & 0xFF00) >> 8; - if (drm_dp_dpcd_write(&intel_dp->aux, INTEL_EDP_BRIGHTNESS_NITS_LSB, buf, 4) < 0) + if (drm_dp_dpcd_write(&intel_dp->aux, INTEL_EDP_BRIGHTNESS_NITS_LSB, buf, + sizeof(buf)) != sizeof(buf)) drm_err(dev, "Failed to write brightness level to DPCD\n"); } @@ -203,7 +205,7 @@ intel_dp_aux_hdr_enable_backlight(const struct intel_crtc_state *crtc_state, u8 old_ctrl, ctrl; ret = drm_dp_dpcd_readb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, &old_ctrl); - if (ret < 0) { + if (ret != 1) { drm_err(&i915->drm, "Failed to read current backlight control mode: %d\n", ret); return; } @@ -221,7 +223,7 @@ intel_dp_aux_hdr_enable_backlight(const struct intel_crtc_state *crtc_state, } if (ctrl != old_ctrl) - if (drm_dp_dpcd_writeb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, ctrl) < 0) + if (drm_dp_dpcd_writeb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, ctrl) != 1) drm_err(&i915->drm, "Failed to configure DPCD brightness controls\n"); } @@ -277,8 +279,7 @@ static void set_vesa_backlight_enable(struct intel_dp *intel_dp, bool enable) if (!(intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP)) return; - if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_DISPLAY_CONTROL_REGISTER, - ®_val) < 0) { + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_DISPLAY_CONTROL_REGISTER, ®_val) != 1) { drm_dbg_kms(&i915->drm, "Failed to read DPCD register 0x%x\n", DP_EDP_DISPLAY_CONTROL_REGISTER); return; @@ -332,8 +333,8 @@ static u32 intel_dp_aux_vesa_get_backlight(struct intel_connector *connector, en if (!intel_dp_aux_vesa_backlight_dpcd_mode(connector)) return connector->panel.backlight.max; - if (drm_dp_dpcd_read(&intel_dp->aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, - &read_val, sizeof(read_val)) < 0) { + if (drm_dp_dpcd_read(&intel_dp->aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, &read_val, + sizeof(read_val)) != sizeof(read_val)) { drm_dbg_kms(&i915->drm, "Failed to read DPCD register 0x%x\n", DP_EDP_BACKLIGHT_BRIGHTNESS_MSB); return 0; @@ -365,8 +366,8 @@ intel_dp_aux_vesa_set_backlight(const struct drm_connector_state *conn_state, vals[0] = (level & 0xFF00) >> 8; vals[1] = (level & 0xFF); } - if (drm_dp_dpcd_write(&intel_dp->aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, - vals, sizeof(vals)) < 0) { + if (drm_dp_dpcd_write(&intel_dp->aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, vals, + sizeof(vals)) != sizeof(vals)) { drm_dbg_kms(&i915->drm, "Failed to write aux backlight level\n"); return; @@ -401,9 +402,8 @@ intel_dp_aux_vesa_enable_backlight(const struct intel_crtc_state *crtc_state, new_dpcd_buf &= ~DP_EDP_BACKLIGHT_CONTROL_MODE_MASK; new_dpcd_buf |= DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD; - if (drm_dp_dpcd_writeb(&intel_dp->aux, - DP_EDP_PWMGEN_BIT_COUNT, - pwmgen_bit_count) < 0) + if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, + pwmgen_bit_count) != 1) drm_dbg_kms(&i915->drm, "Failed to write aux pwmgen bit count\n"); @@ -424,11 +424,9 @@ intel_dp_aux_vesa_enable_backlight(const struct intel_crtc_state *crtc_state, } if (new_dpcd_buf != dpcd_buf) { - if (drm_dp_dpcd_writeb(&intel_dp->aux, - DP_EDP_BACKLIGHT_MODE_SET_REGISTER, new_dpcd_buf) < 0) { - drm_dbg_kms(&i915->drm, - "Failed to write aux backlight mode\n"); - } + if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, + new_dpcd_buf) != 1) + drm_dbg_kms(&i915->drm, "Failed to write aux backlight mode\n"); } intel_dp_aux_vesa_set_backlight(conn_state, level); @@ -519,8 +517,7 @@ static u32 intel_dp_aux_vesa_calc_max_backlight(struct intel_connector *connecto } drm_dbg_kms(&i915->drm, "Using eDP pwmgen bit count of %d\n", pn); - if (drm_dp_dpcd_writeb(&intel_dp->aux, - DP_EDP_PWMGEN_BIT_COUNT, pn) < 0) { + if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, pn) != 1) { drm_dbg_kms(&i915->drm, "Failed to write aux pwmgen bit count\n"); return max_backlight; -- 2.29.2