From patchwork Wed Jan 9 08:19:05 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yoshihiro Shimoda X-Patchwork-Id: 1022315 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pwm-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=renesas.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 43ZMYQ33Tbz9sCX for ; Wed, 9 Jan 2019 19:22:02 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729848AbfAIIWA (ORCPT ); Wed, 9 Jan 2019 03:22:00 -0500 Received: from relmlor2.renesas.com ([210.160.252.172]:5297 "EHLO relmlie6.idc.renesas.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729334AbfAIIWA (ORCPT ); Wed, 9 Jan 2019 03:22:00 -0500 X-IronPort-AV: E=Sophos;i="5.56,456,1539615600"; d="scan'208";a="4541219" Received: from unknown (HELO relmlir6.idc.renesas.com) ([10.200.68.152]) by relmlie6.idc.renesas.com with ESMTP; 09 Jan 2019 17:21:58 +0900 Received: from localhost.localdomain (unknown [10.166.17.210]) by relmlir6.idc.renesas.com (Postfix) with ESMTP id 1811E446E142; Wed, 9 Jan 2019 17:21:58 +0900 (JST) From: Yoshihiro Shimoda To: thierry.reding@gmail.com Cc: linux-pwm@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Yoshihiro Shimoda Subject: [PATCH v3 1/4] pwm: rcar: Add support "atomic" API Date: Wed, 9 Jan 2019 17:19:05 +0900 Message-Id: <1547021948-7664-2-git-send-email-yoshihiro.shimoda.uh@renesas.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1547021948-7664-1-git-send-email-yoshihiro.shimoda.uh@renesas.com> References: <1547021948-7664-1-git-send-email-yoshihiro.shimoda.uh@renesas.com> Sender: linux-pwm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pwm@vger.kernel.org This patch adds support for "atomic" API. This behavior differs with legacy APIs a little. Legacy APIs: The PWMCNT register will be updated in rcar_pwm_config() even if the PWM state is disabled. Atomic API: The PWMCNT register will be updated in rcar_pwm_apply() only if the PWM state is enabled. Otherwize, if a PWM runs with 30% duty cycles and the pwm_apply_state() is called with state->enabled = 0, ->duty_cycle = 60 and ->period = 100, this is possible to output a 60% duty cycle. Signed-off-by: Yoshihiro Shimoda --- drivers/pwm/pwm-rcar.c | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) diff --git a/drivers/pwm/pwm-rcar.c b/drivers/pwm/pwm-rcar.c index a41812f..e3ab663 100644 --- a/drivers/pwm/pwm-rcar.c +++ b/drivers/pwm/pwm-rcar.c @@ -192,12 +192,49 @@ static void rcar_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) rcar_pwm_update(rp, RCAR_PWMCR_EN0, 0, RCAR_PWMCR); } +static int rcar_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) +{ + struct rcar_pwm_chip *rp = to_rcar_pwm_chip(chip); + struct pwm_state cur_state; + int div, ret; + + /* This HW/driver only supports normal polarity */ + pwm_get_state(pwm, &cur_state); + if (state->polarity != PWM_POLARITY_NORMAL) + return -ENOTSUPP; + + if (!state->enabled) { + rcar_pwm_disable(chip, pwm); + return 0; + } + + div = rcar_pwm_get_clock_division(rp, state->period); + if (div < 0) + return div; + + rcar_pwm_update(rp, RCAR_PWMCR_SYNC, RCAR_PWMCR_SYNC, RCAR_PWMCR); + + ret = rcar_pwm_set_counter(rp, div, state->duty_cycle, state->period); + if (!ret) + rcar_pwm_set_clock_control(rp, div); + + /* The SYNC should be set to 0 even if rcar_pwm_set_counter failed */ + rcar_pwm_update(rp, RCAR_PWMCR_SYNC, 0, RCAR_PWMCR); + + if (!ret && state->enabled) + ret = rcar_pwm_enable(chip, pwm); + + return ret; +} + static const struct pwm_ops rcar_pwm_ops = { .request = rcar_pwm_request, .free = rcar_pwm_free, .config = rcar_pwm_config, .enable = rcar_pwm_enable, .disable = rcar_pwm_disable, + .apply = rcar_pwm_apply, .owner = THIS_MODULE, };