From patchwork Mon Mar 21 14:32:20 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fabio Baltieri X-Patchwork-Id: 12787320 Received: from mail-wm1-f50.google.com (mail-wm1-f50.google.com [209.85.128.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AE203369 for ; Mon, 21 Mar 2022 14:32:36 +0000 (UTC) Received: by mail-wm1-f50.google.com with SMTP id 125so356598wmc.3 for ; Mon, 21 Mar 2022 07:32:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=327v7tDtO2GmRxGp/EXz/K90M6uOA2heqpeDOYqPsME=; b=Gme6ELhnFvcMetNZIUvxqYQsfLCOlxkDNaNo+piNbLOzDEbxYZBKO6vEpqZAaB1WnN 81V4Ep3yPDZjGFeOmzqqRtolKOxSDjPAHW/wEE0CCraGO1m2C9LiWpUNwrBLOJV9kAnJ q2gkGbLvZoDdcx7pc6uK07DEGKdqU8qh23TAo= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=327v7tDtO2GmRxGp/EXz/K90M6uOA2heqpeDOYqPsME=; b=KuGGM/NetdTha0YZd0eUipfgG0x2fBQFmi9qk7G3wjvauKZziuoBP57yN2PIof0s8V JnH8s750OJu4sZW377+tfJ6EKlmp9zg5W2kOhr3KhI7dGXcZbgk6kHOhEyTxJrEYqOnu PqnJHKV+rcGPu42R1HFq8xk4vTavmGwVC8Fxs2bgDChGtdvsV/wd1HAX6bmtPmoKirZZ EcKFhQoVtdd2xjZ0uG66f9UUrlr4Th7himgTI+ohV09XNxcy6Iwtp4RPy5y6DrPSw5tS k6/9D0GVCSZb9y19dDLySOjqUtN5mHl6kwpzWFW2a8td7GoWEpY7zkdPWOR7iDZmTUDc dPLQ== X-Gm-Message-State: AOAM531EWf6ZIKOnwVYsZhSYDzdYhT3hF9ISrDc7IjGiu3AG4JdbpUqg I1BA8ao0cKBQgUCJDsGrM5zA0A== X-Google-Smtp-Source: ABdhPJwzl2vh0K7GQ4OXRU1D1Fb+QB9pHhfF1JMG2/3unQTFxnQYcqU9FeomC+1Y42B7ORX5cObwuQ== X-Received: by 2002:a1c:e915:0:b0:37b:d847:e127 with SMTP id q21-20020a1ce915000000b0037bd847e127mr20044602wmc.180.1647873154996; Mon, 21 Mar 2022 07:32:34 -0700 (PDT) Received: from fabiobaltieri-linux.lan ([37.228.205.1]) by smtp.gmail.com with ESMTPSA id u11-20020a05600c19cb00b00389efe9c512sm19092793wmq.23.2022.03.21.07.32.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Mar 2022 07:32:34 -0700 (PDT) From: Fabio Baltieri To: Benson Leung , Guenter Roeck Cc: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Lee Jones , Rob Herring , chrome-platform@lists.linux.dev, linux-pwm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Fabio Baltieri Subject: [PATCH 2/4] drivers: pwm: pwm-cros-ec: add channel type support Date: Mon, 21 Mar 2022 14:32:20 +0000 Message-Id: <20220321143222.2523373-3-fabiobaltieri@chromium.org> X-Mailer: git-send-email 2.35.1.894.gb6a874cedc-goog In-Reply-To: <20220321143222.2523373-1-fabiobaltieri@chromium.org> References: <20220321143222.2523373-1-fabiobaltieri@chromium.org> Precedence: bulk X-Mailing-List: chrome-platform@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 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. Signed-off-by: Fabio Baltieri --- drivers/pwm/pwm-cros-ec.c | 80 +++++++++++++++++++++++++++++++-------- 1 file changed, 65 insertions(+), 15 deletions(-) diff --git a/drivers/pwm/pwm-cros-ec.c b/drivers/pwm/pwm-cros-ec.c index 5e29d9c682c3..77867fd16c49 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. @@ -251,17 +292,26 @@ static int cros_ec_pwm_probe(struct platform_device *pdev) chip = &ec_pwm->chip; ec_pwm->ec = ec; + ec_pwm->use_pwm_type = of_property_read_bool( + dev->of_node, "google,use_pwm_type"); + /* 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);