From nobody Mon Dec 1 23:03:13 2025 Received: from metis.whiteo.stw.pengutronix.de (metis.whiteo.stw.pengutronix.de [185.203.201.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D8CD13009ED for ; Wed, 26 Nov 2025 10:17:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.203.201.7 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764152227; cv=none; b=XEdWX7itWo64YGoLxIj4G6hO0RiuoPZEJyVDKXIo7/FxEc22ylhD9nMdvhuOMzgYADvbpwy1Y9PrKC1Ur7zEPh4ovnWz4KVQLshhlDklGHAaFU8mJd4HGdh88sUSBk44+msMzI5OM9csA2yMVtwtyFE/ljof96Q56h8jazrSQCI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764152227; c=relaxed/simple; bh=M8V6jfE7RgymR7a2gd5FDYaJ9SS0V/zDQuGkP+QUqcs=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=dafOeDw/FThM3n0r9C6E5XRIQ8Tsg+ulzM9xofAY6dqvSz+xEV7qPKnxGRi5Xi/hBSuYzw7xLS3JkW3U99YrLcaTeFI7CEM9rJGTWAoLj4gVarNKJAUpwWvGF7BOI8P0K1ix1p9PNcGOsp6jcIZeLw4+Anc3otGN6zSQsYkgXm0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de; spf=pass smtp.mailfrom=pengutronix.de; arc=none smtp.client-ip=185.203.201.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pengutronix.de Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1vOCZw-0000RW-0r; Wed, 26 Nov 2025 11:16:52 +0100 Received: from moin.white.stw.pengutronix.de ([2a0a:edc0:0:b01:1d::7b] helo=bjornoya.blackshift.org) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1vOCZv-002aSx-15; Wed, 26 Nov 2025 11:16:51 +0100 Received: from hardanger.blackshift.org (p54b152ce.dip0.t-ipconnect.de [84.177.82.206]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) (Authenticated sender: mkl-all@blackshift.org) by smtp.blackshift.org (Postfix) with ESMTPSA id 16D954A88DD; Wed, 26 Nov 2025 10:16:51 +0000 (UTC) From: Marc Kleine-Budde Date: Wed, 26 Nov 2025 11:16:13 +0100 Subject: [PATCH can-next v8 12/17] can: calc_bittiming: replace misleading "nominal" by "reference" Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20251126-canxl-v8-12-e7e3eb74f889@pengutronix.de> References: <20251126-canxl-v8-0-e7e3eb74f889@pengutronix.de> In-Reply-To: <20251126-canxl-v8-0-e7e3eb74f889@pengutronix.de> To: Marc Kleine-Budde , Vincent Mailhol , Oliver Hartkopp Cc: kernel@pengutronix.de, linux-can@vger.kernel.org, linux-kernel@vger.kernel.org, =?utf-8?q?St=C3=A9phane_Grosjean?= X-Mailer: b4 0.15-dev-a6db3 X-Developer-Signature: v=1; a=openpgp-sha256; l=4567; i=mkl@pengutronix.de; h=from:subject:message-id; bh=zfU33+qIh3oomxHhxXPcNk3KNLPMvGySxv+hWnX3g7I=; b=owEBbQGS/pANAwAKAQx0Zd/5kJGcAcsmYgBpJtOHbzDxhx+EWLbkJSCzfNeoZI0f8PicE7uS6 m+qoud6d5qJATMEAAEKAB0WIQSf+wzYr2eoX/wVbPMMdGXf+ZCRnAUCaSbThwAKCRAMdGXf+ZCR nJtTCACX+nd0J58YwEE1RF0Hzkw6Ga3Ctpdb7lhxM7/6rW7nXSLu+WKFweIfrBvRPf2Dl/3ORjf Efhnmomz6n9ez3QhBbH5rIoUmu5klevtmMn2Lst25yqN5DSONxVG2W9hmu9wlMTY1ogfDMMToN2 DllCug2iEiq8JIqsCAvTLmMkfOGtsTaY7ynKBk3AlI8QtqTZOkmK+P31NR+pskQ+ga6zqIzu91K FD1SBhe4t2mo0OiRIaezbGvHuUHaRR3e89SBJLOju81JOdcI6lrXztwz9Y1f3cqUD3Tu/hQC1uo ZoJE9YFyGs9RWKkFkV/4Y7ImhNOZORY6eI85ykK6QkRD+qp+ X-Developer-Key: i=mkl@pengutronix.de; a=openpgp; fpr=C1400BA0B3989E6FBC7D5B5C2B5EE211C58AEA54 X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org From: Vincent Mailhol The functions can_update_sample_point() and can_calc_bittiming() are generic and meant to be used for both the nominal and the data bittiming calculation. However, those functions use misleading terminologies such as "bitrate nominal" or "sample point nominal". Replace all places where the word "nominal" appears with "reference" in order to better distinguish it from the calculated values. Signed-off-by: Vincent Mailhol Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- drivers/net/can/dev/calc_bittiming.c | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-) diff --git a/drivers/net/can/dev/calc_bittiming.c b/drivers/net/can/dev/cal= c_bittiming.c index 268ec6fa7c49..c8c166b383cd 100644 --- a/drivers/net/can/dev/calc_bittiming.c +++ b/drivers/net/can/dev/calc_bittiming.c @@ -24,7 +24,7 @@ */ static int can_update_sample_point(const struct can_bittiming_const *btc, - const unsigned int sample_point_nominal, const unsigned int tseg, + const unsigned int sample_point_reference, const unsigned int tseg, unsigned int *tseg1_ptr, unsigned int *tseg2_ptr, unsigned int *sample_point_error_ptr) { @@ -35,7 +35,7 @@ can_update_sample_point(const struct can_bittiming_const = *btc, =20 for (i =3D 0; i <=3D 1; i++) { tseg2 =3D tseg + CAN_SYNC_SEG - - (sample_point_nominal * (tseg + CAN_SYNC_SEG)) / + (sample_point_reference * (tseg + CAN_SYNC_SEG)) / 1000 - i; tseg2 =3D clamp(tseg2, btc->tseg2_min, btc->tseg2_max); tseg1 =3D tseg - tseg2; @@ -46,9 +46,9 @@ can_update_sample_point(const struct can_bittiming_const = *btc, =20 sample_point =3D 1000 * (tseg + CAN_SYNC_SEG - tseg2) / (tseg + CAN_SYNC_SEG); - sample_point_error =3D abs(sample_point_nominal - sample_point); + sample_point_error =3D abs(sample_point_reference - sample_point); =20 - if (sample_point <=3D sample_point_nominal && + if (sample_point <=3D sample_point_reference && sample_point_error < best_sample_point_error) { best_sample_point =3D sample_point; best_sample_point_error =3D sample_point_error; @@ -68,11 +68,11 @@ int can_calc_bittiming(const struct net_device *dev, st= ruct can_bittiming *bt, { struct can_priv *priv =3D netdev_priv(dev); unsigned int bitrate; /* current bitrate */ - unsigned int bitrate_error; /* difference between current and nominal va= lue */ + unsigned int bitrate_error; /* diff between calculated and reference val= ue */ unsigned int best_bitrate_error =3D UINT_MAX; - unsigned int sample_point_error; /* difference between current and nomina= l value */ + unsigned int sample_point_error; /* diff between calculated and reference= value */ unsigned int best_sample_point_error =3D UINT_MAX; - unsigned int sample_point_nominal; /* nominal sample point */ + unsigned int sample_point_reference; /* reference sample point */ unsigned int best_tseg =3D 0; /* current best value for tseg */ unsigned int best_brp =3D 0; /* current best value for brp */ unsigned int brp, tsegall, tseg, tseg1 =3D 0, tseg2 =3D 0; @@ -81,14 +81,14 @@ int can_calc_bittiming(const struct net_device *dev, st= ruct can_bittiming *bt, =20 /* Use CiA recommended sample points */ if (bt->sample_point) { - sample_point_nominal =3D bt->sample_point; + sample_point_reference =3D bt->sample_point; } else { if (bt->bitrate > 800 * KILO /* BPS */) - sample_point_nominal =3D 750; + sample_point_reference =3D 750; else if (bt->bitrate > 500 * KILO /* BPS */) - sample_point_nominal =3D 800; + sample_point_reference =3D 800; else - sample_point_nominal =3D 875; + sample_point_reference =3D 875; } =20 /* tseg even =3D round down, odd =3D round up */ @@ -115,7 +115,7 @@ int can_calc_bittiming(const struct net_device *dev, st= ruct can_bittiming *bt, if (bitrate_error < best_bitrate_error) best_sample_point_error =3D UINT_MAX; =20 - can_update_sample_point(btc, sample_point_nominal, tseg / 2, + can_update_sample_point(btc, sample_point_reference, tseg / 2, &tseg1, &tseg2, &sample_point_error); if (sample_point_error >=3D best_sample_point_error) continue; @@ -146,7 +146,7 @@ int can_calc_bittiming(const struct net_device *dev, st= ruct can_bittiming *bt, } =20 /* real sample point */ - bt->sample_point =3D can_update_sample_point(btc, sample_point_nominal, + bt->sample_point =3D can_update_sample_point(btc, sample_point_reference, best_tseg, &tseg1, &tseg2, NULL); =20 --=20 2.51.0