From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-106112.protonmail.ch (mail-106112.protonmail.ch [79.135.106.112]) (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 C50AA40B11C for ; Mon, 3 Aug 2026 13:50:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=79.135.106.112 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785765024; cv=none; b=T+bGXvaroIJG0wfjAWdfyY8qYMtPD4egMrdrnMSqGx0t87Xp/vU1p0RggwpjL77U9GTN3AxXVDvGynP32p0+1N88RwLwG5KYOUFfhDCAjHCLDGnfgU1MB39hMoV/1E3HizhEc9hg7twvSnBaylunXDQCfschb8AXhn8FojVOV7A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785765024; c=relaxed/simple; bh=+8sY91Ir3VZGNsRdHN9WUmlpzyrt0U8LrrUR23wXUqA=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=ezv89wOKXhqrtVWEI9IObZdoQZ66L/CQr1NFTnh0I0o5sOlUAHDwUNGGJkIvCE3pWHBZ7Mqa8sJP7Zj4AE18vJZLaHgi1t15sG37ZKjwbE03Yi/HlB9eYVPCrz9tcv1UrzwPNSQ8LKqR7rEi9Mu1q1F5BWL8JLafDBsjdYTDXjY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=geanix.com; spf=pass smtp.mailfrom=geanix.com; dkim=pass (2048-bit key) header.d=geanix.com header.i=@geanix.com header.b=OZcOGZs3; arc=none smtp.client-ip=79.135.106.112 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=geanix.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=geanix.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=geanix.com header.i=@geanix.com header.b="OZcOGZs3" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=geanix.com; s=protonmail3; t=1785765017; x=1786024217; bh=8mkihL4HVfwXlCW8mPeiZgRtVUtEAOyAxLZJyP7ZqmU=; h=From:To:Cc:Subject:Date:Message-ID:From:To:Cc:Date:Subject: Reply-To:Feedback-ID:Message-ID:BIMI-Selector; b=OZcOGZs36B/4OtesLqnhuSL+M9dI1qbV1WDOZ1PWCdeTB5W5Az/8rLzHn6SsNt46N 3bL0FUE43r55dhNj2Qe07Xorpfjxm6bnidFCLEoXsuGAwp7QNe/ayKuAmpdnS+SMC+ sqY83sKyNUAmgKvqxzyCAEWpKLlP+YB0P4Mzn7O6gNXaU8weARtCaj9VLgbHm0zSYQ tV1tfcQGx8hIjQ3QcxgvynzTme9GulH01RgFuN0Jo/XnpexRHvCn4j2mlDUF68UXqQ Glv+IefIdwi+X+F30JLUtkWo1Wa253R5xEBnVkCd3qSUegr+h76t7IXGR/ujixA51b LrpX9bQPyJa2g== X-Pm-Submission-Id: 4hDJ2w1LKSz2Sd3K From: Sean Nyekjaer To: Markus Schneider-Pargmann , Marc Kleine-Budde , Vincent Mailhol Cc: Sean Nyekjaer , linux-can@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3] can: tcan4x5x: put tcan into sleep when removing driver Date: Mon, 3 Aug 2026 15:50:11 +0200 Message-ID: <20260803135011.230006-1-sean@geanix.com> X-Mailer: git-send-email 2.55.0 Precedence: bulk X-Mailing-List: linux-can@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Put the tcan4x5x transceiver into sleep mode when the driver is removed, instead of leaving it in its current operating mode. This reduces power consumption(3mA@12V) once the driver is no longer bound to the device. Signed-off-by: Sean Nyekjaer --- Changes since v1: - Moved enter sleep mode into tcan4x5x_power_enable() Changes since v2: - Added comment about RST pin - Fixed all calls to tcan4x5x_power_enable() drivers/net/can/m_can/tcan4x5x-core.c | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) diff --git a/drivers/net/can/m_can/tcan4x5x-core.c b/drivers/net/can/m_can/tcan4x5x-core.c index 31cc9d0abd45..a318f1874b35 100644 --- a/drivers/net/can/m_can/tcan4x5x-core.c +++ b/drivers/net/can/m_can/tcan4x5x-core.c @@ -211,10 +211,26 @@ static int tcan4x5x_write_fifo(struct m_can_classdev *cdev, return regmap_bulk_write(priv->regmap, TCAN4X5X_MRAM_START + addr_offset, val, val_count); } -static int tcan4x5x_power_enable(struct regulator *reg, int enable) +static int tcan4x5x_power_enable(struct tcan4x5x_priv *priv, int enable) { - if (IS_ERR_OR_NULL(reg)) + struct regulator *reg = priv->power; + + /* + * Check if the power regulator is configured. If it is, just power + * the device on/off. If not, put the device into sleep mode here if + * the RST pin is available, since a wake-up event, RST pin toggle, + * or power cycle are the only ways to exit sleep mode. + * Datasheet: TCAN4550, section "8.4.3 Sleep Mode" + * https://www.ti.com/lit/gpn/tcan4550 + */ + if (IS_ERR_OR_NULL(reg)) { + if (priv->reset_gpio && !enable) + return regmap_update_bits(priv->regmap, TCAN4X5X_CONFIG, + TCAN4X5X_MODE_SEL_MASK, + TCAN4X5X_MODE_SLEEP); + return 0; + } if (enable) return regulator_enable(reg); @@ -476,7 +492,7 @@ static int tcan4x5x_can_probe(struct spi_device *spi) goto out_m_can_class_free_dev; } - ret = tcan4x5x_power_enable(priv->power, 1); + ret = tcan4x5x_power_enable(priv, 1); if (ret) { dev_err(&spi->dev, "Enabling regulator failed %pe\n", ERR_PTR(ret)); @@ -531,7 +547,7 @@ static int tcan4x5x_can_probe(struct spi_device *spi) return 0; out_power: - tcan4x5x_power_enable(priv->power, 0); + tcan4x5x_power_enable(priv, 0); out_m_can_class_free_dev: m_can_class_free_dev(mcan_class->net); return ret; @@ -543,7 +559,7 @@ static void tcan4x5x_can_remove(struct spi_device *spi) m_can_class_unregister(&priv->cdev); - tcan4x5x_power_enable(priv->power, 0); + tcan4x5x_power_enable(priv, 0); m_can_class_free_dev(priv->cdev.net); } -- 2.55.0