From patchwork Wed Jan 16 20:15:15 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sheetal Tigadoli X-Patchwork-Id: 1026185 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=pass (p=quarantine dis=none) header.from=broadcom.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=broadcom.com header.i=@broadcom.com header.b="cHKFfRQ5"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 43fz3H1D3Qz9sMM for ; Thu, 17 Jan 2019 07:15:23 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732447AbfAPUPH (ORCPT ); Wed, 16 Jan 2019 15:15:07 -0500 Received: from mail-yw1-f65.google.com ([209.85.161.65]:38785 "EHLO mail-yw1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732444AbfAPUPG (ORCPT ); Wed, 16 Jan 2019 15:15:06 -0500 Received: by mail-yw1-f65.google.com with SMTP id d190so2938348ywb.5 for ; Wed, 16 Jan 2019 12:15:05 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=broadcom.com; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=awa79T+kyx6VZKS7urmfQCd1R09XTg+c5Pfm4+eLFDE=; b=cHKFfRQ5YKjciYjd8iziH+qR38wH3iMnFxB5C7Xnxrc3Cr4iW9rDOCfaDOdilHUnMN TNon+oSQDVjeUoUZHYw3qaGIrU705oze7rfC5xJpX4dBUsEmcGGt01bt9/8+NlM4xK4h 6fiK4p2Qq0ffUoJ+KxLbIdPfoQ15yez+oeHDM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=awa79T+kyx6VZKS7urmfQCd1R09XTg+c5Pfm4+eLFDE=; b=E7YwVMyr/scvKADVuk54yiXKVSuFDzm1tTiHWrvyzHeHWSEmxMB7JfSN6kTTQ1lu/h jqJLqhkmjsyUICNVlXxnEtNffT0z40z3+DEME5E757TvF1YaFVb72s0B1L/mLal/UlB1 rtNhO5LHcLg06Eq0WtlX6tglxeMWGVYutasL1t+kv3I1Gmj1E45b6UjKWrBGZnrHLAY3 3o0K59qFgSztJQ4iLWsGYoFCHxLwNte6B1LamZokqf9kBwgklhax6fuVx3JXg0bPC1zv 7DIuh6a7/S80E0o8cjo0JxMfp+QEEX3gbk6XPE9ZLL9AswVdI/Qpd63tJeYcInuQ3hOk rnUw== X-Gm-Message-State: AJcUukfvX7EcEb/QwLGT5ySH7wN+502QrKGeQ4IE7iUDScdVJwepHWma Cyz3LT8cfCFv/nkNDYQFuOpAiQ== X-Google-Smtp-Source: ALg8bN7+atlby7ihq5YcsnR59OrsRycWnio8d0DP9VHzmvb+R7NsMJlc/CpqwTUChIoOsKv0xJOYZg== X-Received: by 2002:a81:3358:: with SMTP id z85mr9364471ywz.398.1547669705220; Wed, 16 Jan 2019 12:15:05 -0800 (PST) Received: from shitalt.dhcp.broadcom.net ([192.19.234.250]) by smtp.gmail.com with ESMTPSA id w63sm2541026ywc.46.2019.01.16.12.15.00 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 16 Jan 2019 12:15:04 -0800 (PST) From: Sheetal Tigadoli To: Thierry Reding , Rob Herring , Mark Rutland , Florian Fainelli , Ray Jui , Scott Branden Cc: bcm-kernel-feedback-list@broadcom.com, linux-pwm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Praveen Kumar B , Sheetal Tigadoli Subject: [PATCH V2 3/4] drivers: pwm: pwm-bcm-kona: Add cygnus-pwm support Date: Thu, 17 Jan 2019 01:45:15 +0530 Message-Id: <1547669716-20070-4-git-send-email-sheetal.tigadoli@broadcom.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1547669716-20070-1-git-send-email-sheetal.tigadoli@broadcom.com> References: <1547669716-20070-1-git-send-email-sheetal.tigadoli@broadcom.com> Sender: linux-pwm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pwm@vger.kernel.org From: Praveen Kumar B Add support for new version of pwm-cygnus. Add support to make PWM changes configured and stable. Signed-off-by: Praveen Kumar B Reviewed-by: Ray Jui Reviewed-by: Scott Branden Signed-off-by: Sheetal Tigadoli --- drivers/pwm/pwm-bcm-kona.c | 95 ++++++++++++++++++++++++++++++++++++---------- 1 file changed, 76 insertions(+), 19 deletions(-) diff --git a/drivers/pwm/pwm-bcm-kona.c b/drivers/pwm/pwm-bcm-kona.c index fe63289..143843f 100644 --- a/drivers/pwm/pwm-bcm-kona.c +++ b/drivers/pwm/pwm-bcm-kona.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include @@ -65,10 +66,19 @@ #define DUTY_CYCLE_HIGH_MIN (0x00000000) #define DUTY_CYCLE_HIGH_MAX (0x00ffffff) +#define PWM_MONITOR_OFFSET 0xb0 +#define PWM_MONITOR_TIMEOUT_US 5 + +enum kona_pwmc_ver { + KONA_PWM = 1, + CYGNUS_PWM +}; + struct kona_pwmc { struct pwm_chip chip; void __iomem *base; struct clk *clk; + enum kona_pwmc_ver version; }; static inline struct kona_pwmc *to_kona_pwmc(struct pwm_chip *_chip) @@ -76,10 +86,36 @@ static inline struct kona_pwmc *to_kona_pwmc(struct pwm_chip *_chip) return container_of(_chip, struct kona_pwmc, chip); } +static int kona_pwmc_wait_stable(struct pwm_chip *chip, unsigned int chan, + unsigned int kona_ver) +{ + struct kona_pwmc *kp = to_kona_pwmc(chip); + unsigned int value; + + switch (kona_ver) { + case KONA_PWM: + /* + * There must be a min 400ns delay between clearing trigger and + * settingit. Failing to do this may result in no PWM signal. + */ + ndelay(400); + return 0; + + case CYGNUS_PWM: + return readl_poll_timeout(kp->base + PWM_MONITOR_OFFSET, value, + !(value & (BIT(chan))), 0, + PWM_MONITOR_TIMEOUT_US); + + default: + return -ENODEV; + + } +} + /* * Clear trigger bit but set smooth bit to maintain old output. */ -static void kona_pwmc_prepare_for_settings(struct kona_pwmc *kp, +static int kona_pwmc_prepare_for_settings(struct kona_pwmc *kp, unsigned int chan) { unsigned int value = readl(kp->base + PWM_CONTROL_OFFSET); @@ -88,14 +124,10 @@ static void kona_pwmc_prepare_for_settings(struct kona_pwmc *kp, value &= ~(1 << PWM_CONTROL_TRIGGER_SHIFT(chan)); writel(value, kp->base + PWM_CONTROL_OFFSET); - /* - * There must be a min 400ns delay between clearing trigger and setting - * it. Failing to do this may result in no PWM signal. - */ - ndelay(400); + return kona_pwmc_wait_stable(&kp->chip, chan, kp->version); } -static void kona_pwmc_apply_settings(struct kona_pwmc *kp, unsigned int chan) +static int kona_pwmc_apply_settings(struct kona_pwmc *kp, unsigned int chan) { unsigned int value = readl(kp->base + PWM_CONTROL_OFFSET); @@ -104,8 +136,7 @@ static void kona_pwmc_apply_settings(struct kona_pwmc *kp, unsigned int chan) value |= 1 << PWM_CONTROL_TRIGGER_SHIFT(chan); writel(value, kp->base + PWM_CONTROL_OFFSET); - /* Trigger bit must be held high for at least 400 ns. */ - ndelay(400); + return kona_pwmc_wait_stable(&kp->chip, chan, kp->version); } static void kona_pwmc_disable(struct pwm_chip *chip, struct pwm_device *pwm) @@ -113,8 +144,13 @@ static void kona_pwmc_disable(struct pwm_chip *chip, struct pwm_device *pwm) struct kona_pwmc *kp = to_kona_pwmc(chip); unsigned int chan = pwm->hwpwm; unsigned int value; + int ret; - kona_pwmc_prepare_for_settings(kp, chan); + ret = kona_pwmc_prepare_for_settings(kp, chan); + if (ret < 0) { + dev_err(chip->dev, "failed to prepare pwm settings: %d\n", ret); + return; + } /* Simulate a disable by configuring for zero duty */ writel(0, kp->base + DUTY_CYCLE_HIGH_OFFSET(chan)); @@ -125,7 +161,11 @@ static void kona_pwmc_disable(struct pwm_chip *chip, struct pwm_device *pwm) value &= ~PRESCALE_MASK(chan); writel(value, kp->base + PRESCALE_OFFSET); - kona_pwmc_apply_settings(kp, chan); + ret = kona_pwmc_apply_settings(kp, chan); + if (ret < 0) { + dev_err(chip->dev, "failed to apply pwm settings: %d\n", ret); + return; + } clk_disable_unprepare(kp->clk); } @@ -188,7 +228,12 @@ static int kona_pwmc_apply(struct pwm_chip *chip, struct pwm_device *pwm, } } - kona_pwmc_prepare_for_settings(kp, chan); + ret = kona_pwmc_prepare_for_settings(kp, chan); + if (ret < 0) { + dev_err(chip->dev, + "failed to prepare pwm settings: %d\n", ret); + return ret; + } value = readl(kp->base + PRESCALE_OFFSET); value &= ~PRESCALE_MASK(chan); @@ -208,7 +253,12 @@ static int kona_pwmc_apply(struct pwm_chip *chip, struct pwm_device *pwm, writel(value, kp->base + PWM_CONTROL_OFFSET); } - kona_pwmc_apply_settings(kp, chan); + ret = kona_pwmc_apply_settings(kp, chan); + if (ret < 0) { + dev_err(chip->dev, + "failed to prepare pwm settings: %d\n", ret); + return ret; + } } else if (cstate.enabled) { kona_pwmc_disable(chip, pwm); } @@ -221,14 +271,26 @@ static int kona_pwmc_apply(struct pwm_chip *chip, struct pwm_device *pwm, .owner = THIS_MODULE, }; +static const struct of_device_id bcm_kona_pwmc_dt[] = { + { .compatible = "brcm,kona-pwm", .data = (void *)KONA_PWM}, + { .compatible = "brcm,cygnus-pwm", .data = (void *)CYGNUS_PWM}, + { }, +}; +MODULE_DEVICE_TABLE(of, bcm_kona_pwmc_dt); + static int kona_pwmc_probe(struct platform_device *pdev) { struct kona_pwmc *kp; struct resource *res; + const struct of_device_id *of_id; unsigned int chan; unsigned int value = 0; int ret = 0; + of_id = of_match_node(bcm_kona_pwmc_dt, pdev->dev.of_node); + if (!of_id) + return -ENODEV; + kp = devm_kzalloc(&pdev->dev, sizeof(*kp), GFP_KERNEL); if (kp == NULL) return -ENOMEM; @@ -241,6 +303,7 @@ static int kona_pwmc_probe(struct platform_device *pdev) kp->chip.npwm = 6; kp->chip.of_xlate = of_pwm_xlate_with_flags; kp->chip.of_pwm_n_cells = 3; + kp->version = (enum kona_pwmc_ver)of_id->data; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); kp->base = devm_ioremap_resource(&pdev->dev, res); @@ -287,12 +350,6 @@ static int kona_pwmc_remove(struct platform_device *pdev) return pwmchip_remove(&kp->chip); } -static const struct of_device_id bcm_kona_pwmc_dt[] = { - { .compatible = "brcm,kona-pwm" }, - { }, -}; -MODULE_DEVICE_TABLE(of, bcm_kona_pwmc_dt); - static struct platform_driver kona_pwmc_driver = { .driver = { .name = "bcm-kona-pwm",