From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 7A31E12B94; Tue, 17 Mar 2026 16:44:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773765899; cv=none; b=XngnMp577mpv44Ninu/9SNfx3+WWRXK2zZ0GyyV0xjVL2fIEV0J+Ya9LKsD23YWKIw+nTBi/TS391fSxrXkMm5Cg0gPVFxFpcxcN/UD1nD2ycUg1xNR32z0PBGZNkBfTr1AEkz1p9kbww8WBX1Ulm/RDtzh2n7K4IIW551NrNZw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773765899; c=relaxed/simple; bh=trxxd65tUrsB0Dgn45ThrRHIHUe9744i5pNPXIjSNzs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Lfs7fZrIy1rDHEZQQ1p5wDRvAYTmppMW2txJh2kCQ3ORJ3rxhDrwQ37Scx4sjCmoOl4ieCDQkHMAcSXIDhmcKBs9dmADYw5AwoQDpCrD3JeyW/XRGZ/dTtt8dIfgm7Vt/6n5653WXLzAvx2VzcvbqGClGGSoy0wqetqxZDFD3t4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=NKShB7mJ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="NKShB7mJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DE95AC4CEF7; Tue, 17 Mar 2026 16:44:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1773765899; bh=trxxd65tUrsB0Dgn45ThrRHIHUe9744i5pNPXIjSNzs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NKShB7mJo3y7//6bBdRmxq2xRrbMYplw0a3PBvxK0exIkqdPSXg6FCKWuEC3u8c4Z cm7eW+wrc0+Dac4eGIjkobdCL0PLp3xyVjRyl8fyBJn5tJUNGbEX7YbjRUEq6skM8j O8oT/qF6TwVpL+l1I96xmBoC17R7wmxySuT+nHXI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Marc Kleine-Budde Subject: [PATCH 6.19 120/378] can: gs_usb: gs_can_open(): always configure bitrates before starting device Date: Tue, 17 Mar 2026 17:31:17 +0100 Message-ID: <20260317163011.433415469@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260317163006.959177102@linuxfoundation.org> References: <20260317163006.959177102@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Marc Kleine-Budde commit 2df6162785f31f1bbb598cfc3b08e4efc88f80b6 upstream. So far the driver populated the struct can_priv::do_set_bittiming() and struct can_priv::fd::do_set_data_bittiming() callbacks. Before bringing up the interface, user space has to configure the bitrates. With these callbacks the configuration is directly forwarded into the CAN hardware. Then the interface can be brought up. An ifdown-ifup cycle (without changing the bit rates) doesn't re-configure the bitrates in the CAN hardware. This leads to a problem with the CANable-2.5 [1] firmware, which resets the configured bit rates during ifdown. To fix the problem remove both bit timing callbacks and always configure the bitrates in the struct net_device_ops::ndo_open() callback. [1] https://github.com/Elmue/CANable-2.5-firmware-Slcan-and-Candlelight Cc: stable@vger.kernel.org Fixes: d08e973a77d1 ("can: gs_usb: Added support for the GS_USB CAN devices") Link: https://patch.msgid.link/20260219-gs_usb-always-configure-bitrates-v2-1-671f8ba5b0a5@pengutronix.de Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman --- drivers/net/can/usb/gs_usb.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) --- a/drivers/net/can/usb/gs_usb.c +++ b/drivers/net/can/usb/gs_usb.c @@ -772,9 +772,8 @@ device_detach: } } -static int gs_usb_set_bittiming(struct net_device *netdev) +static int gs_usb_set_bittiming(struct gs_can *dev) { - struct gs_can *dev = netdev_priv(netdev); struct can_bittiming *bt = &dev->can.bittiming; struct gs_device_bittiming dbt = { .prop_seg = cpu_to_le32(bt->prop_seg), @@ -791,9 +790,8 @@ static int gs_usb_set_bittiming(struct n GFP_KERNEL); } -static int gs_usb_set_data_bittiming(struct net_device *netdev) +static int gs_usb_set_data_bittiming(struct gs_can *dev) { - struct gs_can *dev = netdev_priv(netdev); struct can_bittiming *bt = &dev->can.fd.data_bittiming; struct gs_device_bittiming dbt = { .prop_seg = cpu_to_le32(bt->prop_seg), @@ -1057,6 +1055,20 @@ static int gs_can_open(struct net_device if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP) flags |= GS_CAN_MODE_HW_TIMESTAMP; + rc = gs_usb_set_bittiming(dev); + if (rc) { + netdev_err(netdev, "failed to set bittiming: %pe\n", ERR_PTR(rc)); + goto out_usb_kill_anchored_urbs; + } + + if (ctrlmode & CAN_CTRLMODE_FD) { + rc = gs_usb_set_data_bittiming(dev); + if (rc) { + netdev_err(netdev, "failed to set data bittiming: %pe\n", ERR_PTR(rc)); + goto out_usb_kill_anchored_urbs; + } + } + /* finally start device */ dev->can.state = CAN_STATE_ERROR_ACTIVE; dm.flags = cpu_to_le32(flags); @@ -1370,7 +1382,6 @@ static struct gs_can *gs_make_candev(uns dev->can.state = CAN_STATE_STOPPED; dev->can.clock.freq = le32_to_cpu(bt_const.fclk_can); dev->can.bittiming_const = &dev->bt_const; - dev->can.do_set_bittiming = gs_usb_set_bittiming; dev->can.ctrlmode_supported = CAN_CTRLMODE_CC_LEN8_DLC; @@ -1394,7 +1405,6 @@ static struct gs_can *gs_make_candev(uns * GS_CAN_FEATURE_BT_CONST_EXT is set. */ dev->can.fd.data_bittiming_const = &dev->bt_const; - dev->can.fd.do_set_data_bittiming = gs_usb_set_data_bittiming; } if (feature & GS_CAN_FEATURE_TERMINATION) {