From patchwork Tue Feb 28 06:43:36 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Wu X-Patchwork-Id: 733346 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3vXV0C61wYz9s7s for ; Tue, 28 Feb 2017 18:03:07 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751396AbdB1Goh (ORCPT ); Tue, 28 Feb 2017 01:44:37 -0500 Received: from lucky1.263xmail.com ([211.157.147.135]:44424 "EHLO lucky1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750957AbdB1Gof (ORCPT ); Tue, 28 Feb 2017 01:44:35 -0500 Received: from david.wu?rock-chips.com (unknown [192.168.167.139]) by lucky1.263xmail.com (Postfix) with ESMTP id 5E73375C; Tue, 28 Feb 2017 14:42:26 +0800 (CST) X-263anti-spam: KSV:0; X-MAIL-GRAY: 1 X-MAIL-DELIVERY: 0 X-KSVirus-check: 0 X-ABS-CHECKED: 4 Received: from localhost.localdomain (localhost [127.0.0.1]) by smtp.263.net (Postfix) with ESMTP id 202AF5F8; Tue, 28 Feb 2017 14:42:22 +0800 (CST) X-RL-SENDER: david.wu@rock-chips.com X-FST-TO: boris.brezillon@free-electrons.com X-SENDER-IP: 58.22.7.114 X-LOGIN-NAME: david.wu@rock-chips.com X-UNIQUE-TAG: <63c1c4bf5a35ca492ee552ea6adbd403> X-ATTACHMENT-NUM: 0 X-SENDER: wdc@rock-chips.com X-DNS-TYPE: 0 Received: from localhost.localdomain (unknown [58.22.7.114]) by smtp.263.net (Postfix) whith ESMTP id 17685A6IU04; Tue, 28 Feb 2017 14:42:25 +0800 (CST) From: David Wu To: boris.brezillon@free-electrons.com, briannorris@chromium.org, heiko@sntech.de, thierry.reding@gmail.com Cc: dianders@chromium.org, b.galvani@gmail.com, caesar.wang@rock-chips.com, huangtao@rock-chips.com, linux-rockchip@lists.infradead.org, linux-pwm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, "david.wu" Subject: [PATCH] pwm: rockchip: State of pwm clock should synchronize with pwm enabled state Date: Tue, 28 Feb 2017 14:43:36 +0800 Message-Id: <1488264216-9361-1-git-send-email-david.wu@rock-chips.com> X-Mailer: git-send-email 1.9.1 Sender: linux-pwm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pwm@vger.kernel.org From: "david.wu" If the pwm was not enabled at uboot loader, pwm could not work for clock always disabled at pwm driver. The pwm clock is enabled at beginning of pwm_apply(), but disabled at end of pwm_apply(). If the pwm was enabled at uboot loader, pwm clock is always enabled unless closed by ATF. The pwm-backlight might turn off the power at early suspend, should disable pwm clock for saving power consume. It is important to provide opportunity to enable/disable clock at pwm driver, the pwm consumer should ensure correct order to call pwm enable/disable, and pwm driver ensure state of pwm clock synchronized with pwm enabled state. Signed-off-by: David Wu Reviewed-by: Boris Brezillon --- drivers/pwm/pwm-rockchip.c | 38 +++++++++++++++++++++++++++++++------- 1 file changed, 31 insertions(+), 7 deletions(-) diff --git a/drivers/pwm/pwm-rockchip.c b/drivers/pwm/pwm-rockchip.c index ef89df1..14a0445 100644 --- a/drivers/pwm/pwm-rockchip.c +++ b/drivers/pwm/pwm-rockchip.c @@ -191,6 +191,26 @@ static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, return 0; } +static int rk_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm, + bool enable, enum pwm_polarity polarity) +{ + struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); + int ret; + + if (enable) { + ret = clk_enable(pc->clk); + if (ret) + return ret; + } + + pc->data->set_enable(chip, pwm, enable, polarity); + + if (!enable) + clk_disable(pc->clk); + + return 0; +} + static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, struct pwm_state *state) { @@ -207,22 +227,26 @@ static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, return ret; if (state->polarity != curstate.polarity && enabled) { - pc->data->set_enable(chip, pwm, false, state->polarity); + ret = rk_pwm_enable(chip, pwm, false, state->polarity); + if (ret) + goto out; enabled = false; } ret = rockchip_pwm_config(chip, pwm, state->duty_cycle, state->period); if (ret) { if (enabled != curstate.enabled) - pc->data->set_enable(chip, pwm, !enabled, - state->polarity); - + rk_pwm_enable(chip, pwm, !enabled, + state->polarity); goto out; } - if (state->enabled != enabled) - pc->data->set_enable(chip, pwm, state->enabled, - state->polarity); + if (state->enabled != enabled) { + ret = rk_pwm_enable(chip, pwm, state->enabled, + state->polarity); + if (ret) + goto out; + } /* * Update the state with the real hardware, which can differ a bit