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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B70D5C433EF for ; Thu, 21 Apr 2022 08:34:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1381001AbiDUIhn (ORCPT ); Thu, 21 Apr 2022 04:37:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50506 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1386725AbiDUIhm (ORCPT ); Thu, 21 Apr 2022 04:37:42 -0400 Received: from mail-wm1-x329.google.com (mail-wm1-x329.google.com [IPv6:2a00:1450:4864:20::329]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5DE11BB0 for ; Thu, 21 Apr 2022 01:34:52 -0700 (PDT) Received: by mail-wm1-x329.google.com with SMTP id n126-20020a1c2784000000b0038e8af3e788so2886571wmn.1 for ; Thu, 21 Apr 2022 01:34:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=phdOiM7v8LB/lNbA1S0oPciDAvxZxH0KL0yn2KUwBMY=; b=VY45yOQlOGgXr/1Y4TGW0AqqCc3qqK0q9UYQAsu5ZIz9AnUrVopYWVfEZqiFQJKMs7 05t+jYoKjBq0hndJTR0nDXQktmSSq2Mz5ETc2ox2saEA8lnHvvtq2wIqSH6gkgNYryRJ PDWTqRHc2ZtwBFre4crRcHCaEWLRyDgYRq/m0= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=phdOiM7v8LB/lNbA1S0oPciDAvxZxH0KL0yn2KUwBMY=; b=MXn8TYmmGw3r9hsaN1iK6BrHPHDUndxlldQQHxhubZ3UG0TB/0Zn9CbmyEjtESNITE uXHYY+pyCsK9jVMrrL8nU86qbqpOoT55i2OMilzS4tXvKrc/0HO5IKMY4uQrwE1RxKrj BPbTl5ulpowN5TN4+Dj3V2AskjwH1h+vyKnJFWTYI9qQklqmwNNIhtEMwB70cQjF6USv FeRMtZ/MthdkTBWyTYmf/aAt0LQuwlgNoxvzsFTIDurD59A4kr7rf1hxXhOGbqVlg0VM SreTJBQHgsVsAECMfW6dQ8Nuh8r4x+f2hFrW0rFF24qx9vrYiz+DcVoQ44Z5oXiQ+dW7 TvqA== X-Gm-Message-State: AOAM530rK7yRwZEZ9rpwaJn9zVtAfaxrb8x0+VcpqAmABadDwa7JbxPB xbOK9sfIUPZSSljLT/JD/TXwiw== X-Google-Smtp-Source: ABdhPJwptjLh2nrOScT/jPDL/1tK9y+opZ+TXghxZwYOrudVM8T3KTfAo3kFwjffciWZ4wiSMUV02g== X-Received: by 2002:a1c:a101:0:b0:392:942f:3aa with SMTP id k1-20020a1ca101000000b00392942f03aamr7338376wme.1.1650530090853; Thu, 21 Apr 2022 01:34:50 -0700 (PDT) Received: from google.com ([37.228.205.1]) by smtp.gmail.com with ESMTPSA id b3-20020a05600018a300b0020a8b2341f9sm2473455wri.18.2022.04.21.01.34.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Apr 2022 01:34:50 -0700 (PDT) Date: Thu, 21 Apr 2022 08:34:48 +0000 From: Fabio Baltieri To: Prashant Malani Cc: Benson Leung , Guenter Roeck , Thierry Reding , Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= , Lee Jones , Rob Herring , chrome-platform@lists.linux.dev, linux-pwm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Tzung-Bi Shih Subject: Re: [PATCH v5 2/4] pwm: pwm-cros-ec: add channel type support Message-ID: References: <20220420141556.681212-1-fabiobaltieri@chromium.org> <20220420141556.681212-3-fabiobaltieri@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Wed, Apr 20, 2022 at 05:55:35PM +0000, Prashant Malani wrote: > On Apr 20 14:15, Fabio Baltieri wrote: > > Add support for EC_PWM_TYPE_DISPLAY_LIGHT and EC_PWM_TYPE_KB_LIGHT pwm > > types to the PWM cros_ec_pwm driver. This allows specifying one of these > > PWM channel by functionality, and let the EC firmware pick the correct > > channel, thus abstracting the hardware implementation from the kernel > > driver. > > > > To use it, define the node with the "google,cros-ec-pwm-type" > > compatible. > > > > Signed-off-by: Fabio Baltieri > > Reviewed-by: Tzung-Bi Shih > > --- > > drivers/pwm/pwm-cros-ec.c | 82 ++++++++++++++++++++++++++++++++------- > > 1 file changed, 67 insertions(+), 15 deletions(-) > > > > diff --git a/drivers/pwm/pwm-cros-ec.c b/drivers/pwm/pwm-cros-ec.c > > index 5e29d9c682c3..7f10f56c3eb6 100644 > > --- a/drivers/pwm/pwm-cros-ec.c > > +++ b/drivers/pwm/pwm-cros-ec.c > > @@ -12,17 +12,21 @@ > > #include > > #include > > > > +#include > > + > > /** > > * struct cros_ec_pwm_device - Driver data for EC PWM > > * > > * @dev: Device node > > * @ec: Pointer to EC device > > * @chip: PWM controller chip > > + * @use_pwm_type: Use PWM types instead of generic channels > > */ > > struct cros_ec_pwm_device { > > struct device *dev; > > struct cros_ec_device *ec; > > struct pwm_chip chip; > > + bool use_pwm_type; > > }; > > > > /** > > @@ -58,14 +62,31 @@ static void cros_ec_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) > > kfree(channel); > > } > > > > -static int cros_ec_pwm_set_duty(struct cros_ec_device *ec, u8 index, u16 duty) > > +static int cros_ec_dt_type_to_pwm_type(u8 dt_index, u8 *pwm_type) > > { > > + switch (dt_index) { > > + case CROS_EC_PWM_DT_KB_LIGHT: > > + *pwm_type = EC_PWM_TYPE_KB_LIGHT; > > + return 0; > > + case CROS_EC_PWM_DT_DISPLAY_LIGHT: > > + *pwm_type = EC_PWM_TYPE_DISPLAY_LIGHT; > > + return 0; > > + default: > > + return -EINVAL; > > + } > > +} > > + > > +static int cros_ec_pwm_set_duty(struct cros_ec_pwm_device *ec_pwm, u8 index, > > + u16 duty) > > +{ > > + struct cros_ec_device *ec = ec_pwm->ec; > > struct { > > struct cros_ec_command msg; > > struct ec_params_pwm_set_duty params; > > } __packed buf; > > struct ec_params_pwm_set_duty *params = &buf.params; > > struct cros_ec_command *msg = &buf.msg; > > + int ret; > > > > memset(&buf, 0, sizeof(buf)); > > > > @@ -75,14 +96,25 @@ static int cros_ec_pwm_set_duty(struct cros_ec_device *ec, u8 index, u16 duty) > > msg->outsize = sizeof(*params); > > > > params->duty = duty; > > - params->pwm_type = EC_PWM_TYPE_GENERIC; > > - params->index = index; > > + > > + if (ec_pwm->use_pwm_type) { > > + ret = cros_ec_dt_type_to_pwm_type(index, ¶ms->pwm_type); > > + if (ret) { > > + dev_err(ec->dev, "Invalid PWM type index: %d\n", index); > > + return ret; > > + } > > + params->index = 0; > > + } else { > > + params->pwm_type = EC_PWM_TYPE_GENERIC; > > + params->index = index; > > + } > > > > return cros_ec_cmd_xfer_status(ec, msg); > > } > > > > -static int cros_ec_pwm_get_duty(struct cros_ec_device *ec, u8 index) > > +static int cros_ec_pwm_get_duty(struct cros_ec_pwm_device *ec_pwm, u8 index) > > { > > + struct cros_ec_device *ec = ec_pwm->ec; > > struct { > > struct cros_ec_command msg; > > union { > > @@ -102,8 +134,17 @@ static int cros_ec_pwm_get_duty(struct cros_ec_device *ec, u8 index) > > msg->insize = sizeof(*resp); > > msg->outsize = sizeof(*params); > > > > - params->pwm_type = EC_PWM_TYPE_GENERIC; > > - params->index = index; > > + if (ec_pwm->use_pwm_type) { > > + ret = cros_ec_dt_type_to_pwm_type(index, ¶ms->pwm_type); > > + if (ret) { > > + dev_err(ec->dev, "Invalid PWM type index: %d\n", index); > > + return ret; > > + } > > + params->index = 0; > > + } else { > > + params->pwm_type = EC_PWM_TYPE_GENERIC; > > + params->index = index; > > + } > > > > ret = cros_ec_cmd_xfer_status(ec, msg); > > if (ret < 0) > > @@ -133,7 +174,7 @@ static int cros_ec_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, > > */ > > duty_cycle = state->enabled ? state->duty_cycle : 0; > > > > - ret = cros_ec_pwm_set_duty(ec_pwm->ec, pwm->hwpwm, duty_cycle); > > + ret = cros_ec_pwm_set_duty(ec_pwm, pwm->hwpwm, duty_cycle); > > if (ret < 0) > > return ret; > > > > @@ -149,7 +190,7 @@ static void cros_ec_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, > > struct cros_ec_pwm *channel = pwm_get_chip_data(pwm); > > int ret; > > > > - ret = cros_ec_pwm_get_duty(ec_pwm->ec, pwm->hwpwm); > > + ret = cros_ec_pwm_get_duty(ec_pwm, pwm->hwpwm); > > if (ret < 0) { > > dev_err(chip->dev, "error getting initial duty: %d\n", ret); > > return; > > @@ -204,13 +245,13 @@ static const struct pwm_ops cros_ec_pwm_ops = { > > * of PWMs it supports directly, so we have to read the pwm duty cycle for > > * subsequent channels until we get an error. > > */ > > -static int cros_ec_num_pwms(struct cros_ec_device *ec) > > +static int cros_ec_num_pwms(struct cros_ec_pwm_device *ec_pwm) > > { > > int i, ret; > > > > /* The index field is only 8 bits */ > > for (i = 0; i <= U8_MAX; i++) { > > - ret = cros_ec_pwm_get_duty(ec, i); > > + ret = cros_ec_pwm_get_duty(ec_pwm, i); > > /* > > * We look for SUCCESS, INVALID_COMMAND, or INVALID_PARAM > > * responses; everything else is treated as an error. > > @@ -236,6 +277,7 @@ static int cros_ec_pwm_probe(struct platform_device *pdev) > > { > > struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent); > > struct device *dev = &pdev->dev; > > + struct device_node *np = pdev->dev.of_node; > > struct cros_ec_pwm_device *ec_pwm; > > struct pwm_chip *chip; > > int ret; > > @@ -251,17 +293,26 @@ static int cros_ec_pwm_probe(struct platform_device *pdev) > > chip = &ec_pwm->chip; > > ec_pwm->ec = ec; > > > > + if (of_device_is_compatible(np, "google,cros-ec-pwm-type")) > > + ec_pwm->use_pwm_type = true; > > Isn't it possible to just use an optional boolean property > (for example: "use-pwm-type") instead of defining a new compatible > string? Yeah that's what I did originally but Rob suggested to use a new compatible instead: https://lore.kernel.org/chrome-platform/Yk20uTE%2FVdm2c6jI@robh.at.kernel.org/ > > + > > /* PWM chip */ > > chip->dev = dev; > > chip->ops = &cros_ec_pwm_ops; > > chip->of_xlate = cros_ec_pwm_xlate; > > chip->of_pwm_n_cells = 1; > > - ret = cros_ec_num_pwms(ec); > > - if (ret < 0) { > > - dev_err(dev, "Couldn't find PWMs: %d\n", ret); > > - return ret; > > + > > + if (ec_pwm->use_pwm_type) { > > + chip->npwm = CROS_EC_PWM_DT_COUNT; > > + } else { > > + ret = cros_ec_num_pwms(ec_pwm); > > + if (ret < 0) { > > + dev_err(dev, "Couldn't find PWMs: %d\n", ret); > > + return ret; > > + } > > + chip->npwm = ret; > > } > > - chip->npwm = ret; > > + > > dev_dbg(dev, "Probed %u PWMs\n", chip->npwm); > > > > ret = pwmchip_add(chip); > > @@ -288,6 +339,7 @@ static int cros_ec_pwm_remove(struct platform_device *dev) > > #ifdef CONFIG_OF > > static const struct of_device_id cros_ec_pwm_of_match[] = { > > { .compatible = "google,cros-ec-pwm" }, > > + { .compatible = "google,cros-ec-pwm-type" }, > > {}, > > }; > > MODULE_DEVICE_TABLE(of, cros_ec_pwm_of_match); > > -- > > 2.36.0.rc0.470.gd361397f0d-goog > > > > -- Fabio Baltieri