From patchwork Tue Aug 25 10:01:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 1350975 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-pwm-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=NH9ddXem; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4BbPgG5b0yz9sSP for ; Tue, 25 Aug 2020 20:02:34 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726000AbgHYKCe (ORCPT ); Tue, 25 Aug 2020 06:02:34 -0400 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:59622 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729696AbgHYKCe (ORCPT ); Tue, 25 Aug 2020 06:02:34 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1598349751; 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=/YPmN7T3xJE/+frGqhxzW0NYPAyDFqqCzUViYE2S5SM=; b=NH9ddXemLXr1sQk1anTO5BBuTDSw3jSagSBovO6pH1we0uPWyTQaRIzzGfGWdbEohZzW5N TM3TaE7FQWBxSQZ3+xqd8pIeOEN3VstzGa4YBoGvv+xS5R18Z53PRXJsyL2ELYx5BU6LXj duv6OXaTQVotql0V4eDiqvPlD/qkFlo= 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-535-qNfu6qwANm-qTEzHhtrU2Q-1; Tue, 25 Aug 2020 06:02:29 -0400 X-MC-Unique: qNfu6qwANm-qTEzHhtrU2Q-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 8478D1015CAD; Tue, 25 Aug 2020 10:02:22 +0000 (UTC) Received: from x1.localdomain.com (ovpn-114-132.ams2.redhat.com [10.36.114.132]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2A7EC808BA; Tue, 25 Aug 2020 10:02:18 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Cc: Hans de Goede , linux-pwm@vger.kernel.org, intel-gfx , dri-devel@lists.freedesktop.org, Andy Shevchenko , Mika Westerberg , linux-acpi@vger.kernel.org, Jani Nikula Subject: [PATCH v7 16/16] drm/i915: panel: Use atomic PWM API for devs with an external PWM controller Date: Tue, 25 Aug 2020 12:01:06 +0200 Message-Id: <20200825100106.61941-17-hdegoede@redhat.com> In-Reply-To: <20200825100106.61941-1-hdegoede@redhat.com> References: <20200825100106.61941-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Sender: linux-pwm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pwm@vger.kernel.org Now that the PWM drivers which we use have been converted to the atomic PWM API, we can move the i915 panel code over to using the atomic PWM API. The removes a long standing FIXME and this removes a flicker where the backlight brightness would jump to 100% when i915 loads even if using the fastset path. Note that this commit also simplifies pwm_disable_backlight(), by dropping the intel_panel_actually_set_backlight(..., 0) call. This call sets the PWM to 0% duty-cycle. I believe that this call was only present as a workaround for a bug in the pwm-crc.c driver where it failed to clear the PWM_OUTPUT_ENABLE bit. This is fixed by an earlier patch in this series. After the dropping of this workaround, the usleep call, which seems unnecessary to begin with, has no useful effect anymore, so drop that too. Acked-by: Jani Nikula Signed-off-by: Hans de Goede --- Changes in v7: - Fix a u64 divide leading to undefined reference to `__udivdi3' errors on 32 bit platforms by casting the divisor to an unsigned long Changes in v6: - Drop the pwm_get_period() check in pwm_setup(), it is now longer needed now that we use pwm_get_relative_duty_cycle() Changes in v4: - Add a note to the commit message about the dropping of the intel_panel_actually_set_backlight() and usleep() calls from pwm_disable_backlight() - Use the pwm_set/get_relative_duty_cycle() helpers instead of using DIY code for this --- .../drm/i915/display/intel_display_types.h | 3 +- drivers/gpu/drm/i915/display/intel_panel.c | 70 ++++++++----------- 2 files changed, 33 insertions(+), 40 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h index 7171e7c8d928..e3ebe7c313ba 100644 --- a/drivers/gpu/drm/i915/display/intel_display_types.h +++ b/drivers/gpu/drm/i915/display/intel_display_types.h @@ -28,6 +28,7 @@ #include #include +#include #include #include @@ -223,7 +224,7 @@ struct intel_panel { bool util_pin_active_low; /* bxt+ */ u8 controller; /* bxt+ only */ struct pwm_device *pwm; - int pwm_period_ns; + struct pwm_state pwm_state; /* DPCD backlight */ u8 pwmgen_bit_count; diff --git a/drivers/gpu/drm/i915/display/intel_panel.c b/drivers/gpu/drm/i915/display/intel_panel.c index 6d27630dd1e4..5a201fe8de11 100644 --- a/drivers/gpu/drm/i915/display/intel_panel.c +++ b/drivers/gpu/drm/i915/display/intel_panel.c @@ -592,10 +592,10 @@ static u32 bxt_get_backlight(struct intel_connector *connector) static u32 pwm_get_backlight(struct intel_connector *connector) { struct intel_panel *panel = &connector->panel; - int duty_ns; + struct pwm_state state; - duty_ns = pwm_get_duty_cycle(panel->backlight.pwm); - return DIV_ROUND_UP(duty_ns * 100, panel->backlight.pwm_period_ns); + pwm_get_state(panel->backlight.pwm, &state); + return pwm_get_relative_duty_cycle(&state, 100); } static void lpt_set_backlight(const struct drm_connector_state *conn_state, u32 level) @@ -669,10 +669,9 @@ static void bxt_set_backlight(const struct drm_connector_state *conn_state, u32 static void pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level) { struct intel_panel *panel = &to_intel_connector(conn_state->connector)->panel; - int duty_ns = DIV_ROUND_UP(level * panel->backlight.pwm_period_ns, 100); - pwm_config(panel->backlight.pwm, duty_ns, - panel->backlight.pwm_period_ns); + pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100); + pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state); } static void @@ -841,10 +840,8 @@ static void pwm_disable_backlight(const struct drm_connector_state *old_conn_sta struct intel_connector *connector = to_intel_connector(old_conn_state->connector); struct intel_panel *panel = &connector->panel; - /* Disable the backlight */ - intel_panel_actually_set_backlight(old_conn_state, 0); - usleep_range(2000, 3000); - pwm_disable(panel->backlight.pwm); + panel->backlight.pwm_state.enabled = false; + pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state); } void intel_panel_disable_backlight(const struct drm_connector_state *old_conn_state) @@ -1176,9 +1173,12 @@ static void pwm_enable_backlight(const struct intel_crtc_state *crtc_state, { struct intel_connector *connector = to_intel_connector(conn_state->connector); struct intel_panel *panel = &connector->panel; + int level = panel->backlight.level; - pwm_enable(panel->backlight.pwm); - intel_panel_actually_set_backlight(conn_state, panel->backlight.level); + level = intel_panel_compute_brightness(connector, level); + pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100); + panel->backlight.pwm_state.enabled = true; + pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state); } static void __intel_panel_enable_backlight(const struct intel_crtc_state *crtc_state, @@ -1897,8 +1897,7 @@ static int pwm_setup_backlight(struct intel_connector *connector, struct drm_i915_private *dev_priv = to_i915(dev); struct intel_panel *panel = &connector->panel; const char *desc; - u32 level, ns; - int retval; + u32 level; /* Get the right PWM chip for DSI backlight according to VBT */ if (dev_priv->vbt.dsi.config->pwm_blc == PPS_BLC_PMIC) { @@ -1916,35 +1915,28 @@ static int pwm_setup_backlight(struct intel_connector *connector, return -ENODEV; } - panel->backlight.pwm_period_ns = NSEC_PER_SEC / - get_vbt_pwm_freq(dev_priv); - - /* - * FIXME: pwm_apply_args() should be removed when switching to - * the atomic PWM API. - */ - pwm_apply_args(panel->backlight.pwm); - panel->backlight.max = 100; /* 100% */ panel->backlight.min = get_backlight_min_vbt(connector); - level = intel_panel_compute_brightness(connector, 100); - ns = DIV_ROUND_UP(level * panel->backlight.pwm_period_ns, 100); - retval = pwm_config(panel->backlight.pwm, ns, - panel->backlight.pwm_period_ns); - if (retval < 0) { - drm_err(&dev_priv->drm, "Failed to configure the pwm chip\n"); - pwm_put(panel->backlight.pwm); - panel->backlight.pwm = NULL; - return retval; - } + if (pwm_is_enabled(panel->backlight.pwm)) { + /* PWM is already enabled, use existing settings */ + pwm_get_state(panel->backlight.pwm, &panel->backlight.pwm_state); - level = DIV_ROUND_UP_ULL(pwm_get_duty_cycle(panel->backlight.pwm) * 100, - panel->backlight.pwm_period_ns); - level = intel_panel_compute_brightness(connector, level); - panel->backlight.level = clamp(level, panel->backlight.min, - panel->backlight.max); - panel->backlight.enabled = panel->backlight.level != 0; + level = pwm_get_relative_duty_cycle(&panel->backlight.pwm_state, + 100); + level = intel_panel_compute_brightness(connector, level); + panel->backlight.level = clamp(level, panel->backlight.min, + panel->backlight.max); + panel->backlight.enabled = true; + + drm_dbg_kms(&dev_priv->drm, "PWM already enabled at freq %ld, VBT freq %d, level %d\n", + NSEC_PER_SEC / (unsigned long)panel->backlight.pwm_state.period, + get_vbt_pwm_freq(dev_priv), level); + } else { + /* Set period from VBT frequency, leave other settings at 0. */ + panel->backlight.pwm_state.period = + NSEC_PER_SEC / get_vbt_pwm_freq(dev_priv); + } drm_info(&dev_priv->drm, "Using %s PWM for LCD backlight control\n", desc);