From patchwork Tue Feb 27 17:37:59 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fabrice Gasnier X-Patchwork-Id: 13574228 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 404DDC5478C for ; Tue, 27 Feb 2024 17:40:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=sMUpw94YDQSLO1JRzdMMV+80yNp9z2iVDmIDZzf93As=; b=L0vsX/OIbP6WWQ g+SVwzym1boEh9M8QU3JtBx2rxlL+fdhs1we/mvU30b+OflKjq/jxpOaMJAt6pVt25W0NmHpNcVwt rIGnSQ+VShDDH32ecKFYx2Jm9UVvppeo9ABHoczjQSpvQjG+O2tBB3G666a/ml9wXutj/mM0wfmFo CYAHrSgcFUhwf2pl42223rWyjwb9FhcUXonCHvk8c9ocOLFw2etOMMGVEhC0HnAJVk83kF2qM7Wex jPwnptC4DZOHuaXRmTYypH0wGc61b7Gg8lXMROt6Jz0qrBkUPCMNf0x4rx4Zg3n868IaYk7SPeJ6t TzbNz170TABew+qv11uA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rf1RU-00000006GKe-00mm; Tue, 27 Feb 2024 17:40:36 +0000 Received: from mx08-00178001.pphosted.com ([91.207.212.93] helo=mx07-00178001.pphosted.com) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rf1R4-00000006G6c-0yq7 for linux-arm-kernel@lists.infradead.org; Tue, 27 Feb 2024 17:40:11 +0000 Received: from pps.filterd (m0046660.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.17.1.24/8.17.1.24) with ESMTP id 41RBiEqa010578; Tue, 27 Feb 2024 18:40:03 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding:content-type; s= selector1; bh=0rgZzVeIciD13wzGBJT0MITILPsQC7SVf3hIqPrhzFs=; b=Sb OZ33wPV2WCL4ph2yUE/gXByJRsoDCIKuLAsgnfs2yeLbCeQ6JpLyRA2k2QZSDwhE i41K0N36mUT1xMQPxTzLsa1TPYQgyY2th6Y8JAr7cbU1cNECbux3vLO89GItliBR 9Jtmhq21uoXgs5VxIaiFSugyupAnHgoX1nm2y8MigMhg91/CJslWGIz4YyApTt3j lpHFzcbxSrAkrOrP6bRdbV/N6nmKyc6zHoogaJfyDlazM8C+AJkb4AjbjtbDj48x pjmxWz+ZxsoM5jjnwcOEMcO9IAXgFLe56y9hg+u8r0bfyEfSlArfcHHhuOjcQRaI 41gWYV09BOaHr/5gcrCw== Received: from beta.dmz-ap.st.com (beta.dmz-ap.st.com [138.198.100.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 3whf4cscea-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 27 Feb 2024 18:40:03 +0100 (CET) Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-ap.st.com (STMicroelectronics) with ESMTP id E6CB040044; Tue, 27 Feb 2024 18:39:59 +0100 (CET) Received: from Webmail-eu.st.com (shfdag1node2.st.com [10.75.129.70]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 28A832AD132; Tue, 27 Feb 2024 18:39:30 +0100 (CET) Received: from localhost (10.252.26.109) by SHFDAG1NODE2.st.com (10.75.129.70) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27; Tue, 27 Feb 2024 18:39:29 +0100 From: Fabrice Gasnier To: CC: , , , , , , Subject: [PATCH v4 07/11] counter: stm32-timer-cnt: add checks on quadrature encoder capability Date: Tue, 27 Feb 2024 18:37:59 +0100 Message-ID: <20240227173803.53906-8-fabrice.gasnier@foss.st.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240227173803.53906-1-fabrice.gasnier@foss.st.com> References: <20240227173803.53906-1-fabrice.gasnier@foss.st.com> MIME-Version: 1.0 X-Originating-IP: [10.252.26.109] X-ClientProxiedBy: SHFCAS1NODE2.st.com (10.75.129.73) To SHFDAG1NODE2.st.com (10.75.129.70) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.1011,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2024-02-27_05,2024-02-27_01,2023-05-22_02 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240227_094010_571146_28CE19DE X-CRM114-Status: GOOD ( 21.48 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org This is a precursor patch to support capture channels on all possible channels and stm32 timer types. Original driver was intended to be used only as quadrature encoder and simple counter on internal clock. So, add a check on encoder capability, so the driver may be probed for timer instances without encoder feature. This way, all timers may be used as simple counter on internal clock, starting from here. Encoder capability is retrieved by using the timer index (originally in stm32-timer-trigger driver and dt-bindings). The need to keep backward compatibility with existing device tree lead to parse aside trigger node. Signed-off-by: Fabrice Gasnier Reviewed-by: William Breathitt Gray --- Changes in v4: - drop idx from struct stm32_timer_cnt as unused after probing - directly use dev struct in stm32_timer_cnt_probe_encoder routine. Changes in v3: - New patch split from: "counter: stm32-timer-cnt: populate capture channels and check encoder" - return -EOPNOTSUPP when encoder function isn't supported by the timer instance. --- drivers/counter/stm32-timer-cnt.c | 55 +++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) diff --git a/drivers/counter/stm32-timer-cnt.c b/drivers/counter/stm32-timer-cnt.c index e0709dd7dcfd..144e040fa457 100644 --- a/drivers/counter/stm32-timer-cnt.c +++ b/drivers/counter/stm32-timer-cnt.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -38,6 +39,7 @@ struct stm32_timer_cnt { u32 max_arr; bool enabled; struct stm32_timer_regs bak; + bool has_encoder; }; static const enum counter_function stm32_count_functions[] = { @@ -111,12 +113,18 @@ static int stm32_count_function_write(struct counter_device *counter, sms = TIM_SMCR_SMS_SLAVE_MODE_DISABLED; break; case COUNTER_FUNCTION_QUADRATURE_X2_A: + if (!priv->has_encoder) + return -EOPNOTSUPP; sms = TIM_SMCR_SMS_ENCODER_MODE_1; break; case COUNTER_FUNCTION_QUADRATURE_X2_B: + if (!priv->has_encoder) + return -EOPNOTSUPP; sms = TIM_SMCR_SMS_ENCODER_MODE_2; break; case COUNTER_FUNCTION_QUADRATURE_X4: + if (!priv->has_encoder) + return -EOPNOTSUPP; sms = TIM_SMCR_SMS_ENCODER_MODE_3; break; default: @@ -388,6 +396,49 @@ static struct counter_count stm32_counts = { .num_ext = ARRAY_SIZE(stm32_count_ext) }; +/* encoder supported on TIM1 TIM2 TIM3 TIM4 TIM5 TIM8 */ +#define STM32_TIM_ENCODER_SUPPORTED (BIT(0) | BIT(1) | BIT(2) | BIT(3) | BIT(4) | BIT(7)) + +static const char * const stm32_timer_trigger_compat[] = { + "st,stm32-timer-trigger", + "st,stm32h7-timer-trigger", +}; + +static int stm32_timer_cnt_probe_encoder(struct device *dev, + struct stm32_timer_cnt *priv) +{ + struct device *parent = dev->parent; + struct device_node *tnode = NULL, *pnode = parent->of_node; + int i, ret; + u32 idx; + + /* + * Need to retrieve the trigger node index from DT, to be able + * to determine if the counter supports encoder mode. It also + * enforce backward compatibility, and allow to support other + * counter modes in this driver (when the timer doesn't support + * encoder). + */ + for (i = 0; i < ARRAY_SIZE(stm32_timer_trigger_compat) && !tnode; i++) + tnode = of_get_compatible_child(pnode, stm32_timer_trigger_compat[i]); + if (!tnode) { + dev_err(dev, "Can't find trigger node\n"); + return -ENODATA; + } + + ret = of_property_read_u32(tnode, "reg", &idx); + if (ret) { + dev_err(dev, "Can't get index (%d)\n", ret); + return ret; + } + + priv->has_encoder = !!(STM32_TIM_ENCODER_SUPPORTED & BIT(idx)); + + dev_dbg(dev, "encoder support: %s\n", priv->has_encoder ? "yes" : "no"); + + return 0; +} + static int stm32_timer_cnt_probe(struct platform_device *pdev) { struct stm32_timers *ddata = dev_get_drvdata(pdev->dev.parent); @@ -409,6 +460,10 @@ static int stm32_timer_cnt_probe(struct platform_device *pdev) priv->clk = ddata->clk; priv->max_arr = ddata->max_arr; + ret = stm32_timer_cnt_probe_encoder(dev, priv); + if (ret) + return ret; + counter->name = dev_name(dev); counter->parent = dev; counter->ops = &stm32_timer_cnt_ops;