<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/net/can, branch linux-6.11.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>can: {cc770,sja1000}_isa: allow building on x86_64</title>
<updated>2024-11-14T12:21:04+00:00</updated>
<author>
<name>Thomas Mühlbacher</name>
<email>tmuehlbacher@posteo.net</email>
</author>
<published>2024-09-19T17:35:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7f2b4b4bb1d91614b1687e5e9c0bb56d59a3e02f'/>
<id>7f2b4b4bb1d91614b1687e5e9c0bb56d59a3e02f</id>
<content type='text'>
commit 7b22846f8af5ab2f267de9eb209fb1835ee9978c upstream.

The ISA variable is only defined if X86_32 is also defined. However,
these drivers are still useful and in use on at least some modern 64-bit
x86 industrial systems as well. With the correct module parameters, they
work as long as IO port communication is possible, despite their name
having ISA in them.

Fixes: a29689e60ed3 ("net: handle HAS_IOPORT dependencies")
Signed-off-by: Thomas Mühlbacher &lt;tmuehlbacher@posteo.net&gt;
Link: https://patch.msgid.link/20240919174151.15473-2-tmuehlbacher@posteo.net
Cc: stable@vger.kernel.org
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 7b22846f8af5ab2f267de9eb209fb1835ee9978c upstream.

The ISA variable is only defined if X86_32 is also defined. However,
these drivers are still useful and in use on at least some modern 64-bit
x86 industrial systems as well. With the correct module parameters, they
work as long as IO port communication is possible, despite their name
having ISA in them.

Fixes: a29689e60ed3 ("net: handle HAS_IOPORT dependencies")
Signed-off-by: Thomas Mühlbacher &lt;tmuehlbacher@posteo.net&gt;
Link: https://patch.msgid.link/20240919174151.15473-2-tmuehlbacher@posteo.net
Cc: stable@vger.kernel.org
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>can: mcp251xfd: mcp251xfd_ring_alloc(): fix coalescing configuration when switching CAN modes</title>
<updated>2024-11-14T12:21:04+00:00</updated>
<author>
<name>Marc Kleine-Budde</name>
<email>mkl@pengutronix.de</email>
</author>
<published>2024-10-25T12:34:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c9c6a97d89c5367a33dd9dfd549daf3a4249eab7'/>
<id>c9c6a97d89c5367a33dd9dfd549daf3a4249eab7</id>
<content type='text'>
commit eb9a839b3d8a989be5970035a5cf29bcd6ffd24d upstream.

Since commit 50ea5449c563 ("can: mcp251xfd: fix ring configuration
when switching from CAN-CC to CAN-FD mode"), the current ring and
coalescing configuration is passed to can_ram_get_layout(). That fixed
the issue when switching between CAN-CC and CAN-FD mode with
configured ring (rx, tx) and/or coalescing parameters (rx-frames-irq,
tx-frames-irq).

However 50ea5449c563 ("can: mcp251xfd: fix ring configuration when
switching from CAN-CC to CAN-FD mode"), introduced a regression when
switching CAN modes with disabled coalescing configuration: Even if
the previous CAN mode has no coalescing configured, the new mode is
configured with active coalescing. This leads to delayed receiving of
CAN-FD frames.

This comes from the fact, that ethtool uses usecs = 0 and max_frames =
1 to disable coalescing, however the driver uses internally
priv-&gt;{rx,tx}_obj_num_coalesce_irq = 0 to indicate disabled
coalescing.

Fix the regression by assigning struct ethtool_coalesce
ec-&gt;{rx,tx}_max_coalesced_frames_irq = 1 if coalescing is disabled in
the driver as can_ram_get_layout() expects this.

Reported-by: https://github.com/vdh-robothania
Closes: https://github.com/raspberrypi/linux/issues/6407
Fixes: 50ea5449c563 ("can: mcp251xfd: fix ring configuration when switching from CAN-CC to CAN-FD mode")
Cc: stable@vger.kernel.org
Reviewed-by: Simon Horman &lt;horms@kernel.org&gt;
Link: https://patch.msgid.link/20241025-mcp251xfd-fix-coalesing-v1-1-9d11416de1df@pengutronix.de
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit eb9a839b3d8a989be5970035a5cf29bcd6ffd24d upstream.

Since commit 50ea5449c563 ("can: mcp251xfd: fix ring configuration
when switching from CAN-CC to CAN-FD mode"), the current ring and
coalescing configuration is passed to can_ram_get_layout(). That fixed
the issue when switching between CAN-CC and CAN-FD mode with
configured ring (rx, tx) and/or coalescing parameters (rx-frames-irq,
tx-frames-irq).

However 50ea5449c563 ("can: mcp251xfd: fix ring configuration when
switching from CAN-CC to CAN-FD mode"), introduced a regression when
switching CAN modes with disabled coalescing configuration: Even if
the previous CAN mode has no coalescing configured, the new mode is
configured with active coalescing. This leads to delayed receiving of
CAN-FD frames.

This comes from the fact, that ethtool uses usecs = 0 and max_frames =
1 to disable coalescing, however the driver uses internally
priv-&gt;{rx,tx}_obj_num_coalesce_irq = 0 to indicate disabled
coalescing.

Fix the regression by assigning struct ethtool_coalesce
ec-&gt;{rx,tx}_max_coalesced_frames_irq = 1 if coalescing is disabled in
the driver as can_ram_get_layout() expects this.

Reported-by: https://github.com/vdh-robothania
Closes: https://github.com/raspberrypi/linux/issues/6407
Fixes: 50ea5449c563 ("can: mcp251xfd: fix ring configuration when switching from CAN-CC to CAN-FD mode")
Cc: stable@vger.kernel.org
Reviewed-by: Simon Horman &lt;horms@kernel.org&gt;
Link: https://patch.msgid.link/20241025-mcp251xfd-fix-coalesing-v1-1-9d11416de1df@pengutronix.de
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>can: mcp251xfd: mcp251xfd_get_tef_len(): fix length calculation</title>
<updated>2024-11-14T12:21:04+00:00</updated>
<author>
<name>Marc Kleine-Budde</name>
<email>mkl@pengutronix.de</email>
</author>
<published>2024-10-01T14:56:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d7cb0c521d3ace3b17062ea7f0d28c21b957909c'/>
<id>d7cb0c521d3ace3b17062ea7f0d28c21b957909c</id>
<content type='text'>
commit 3c1c18551e6ac1b988d0a05c5650e3f6c95a1b8a upstream.

Commit b8e0ddd36ce9 ("can: mcp251xfd: tef: prepare to workaround
broken TEF FIFO tail index erratum") introduced
mcp251xfd_get_tef_len() to get the number of unhandled transmit events
from the Transmit Event FIFO (TEF).

As the TEF has no head pointer, the driver uses the TX FIFO's tail
pointer instead, assuming that send frames are completed. However the
check for the TEF being full was not correct. This leads to the driver
stop working if the TEF is full.

Fix the TEF full check by assuming that if, from the driver's point of
view, there are no free TX buffers in the chip and the TX FIFO is
empty, all messages must have been sent and the TEF must therefore be
full.

Reported-by: Sven Schuchmann &lt;schuchmann@schleissheimer.de&gt;
Closes: https://patch.msgid.link/FR3P281MB155216711EFF900AD9791B7ED9692@FR3P281MB1552.DEUP281.PROD.OUTLOOK.COM
Fixes: b8e0ddd36ce9 ("can: mcp251xfd: tef: prepare to workaround broken TEF FIFO tail index erratum")
Tested-by: Sven Schuchmann &lt;schuchmann@schleissheimer.de&gt;
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20241104-mcp251xfd-fix-length-calculation-v3-1-608b6e7e2197@pengutronix.de
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 3c1c18551e6ac1b988d0a05c5650e3f6c95a1b8a upstream.

Commit b8e0ddd36ce9 ("can: mcp251xfd: tef: prepare to workaround
broken TEF FIFO tail index erratum") introduced
mcp251xfd_get_tef_len() to get the number of unhandled transmit events
from the Transmit Event FIFO (TEF).

As the TEF has no head pointer, the driver uses the TX FIFO's tail
pointer instead, assuming that send frames are completed. However the
check for the TEF being full was not correct. This leads to the driver
stop working if the TEF is full.

Fix the TEF full check by assuming that if, from the driver's point of
view, there are no free TX buffers in the chip and the TX FIFO is
empty, all messages must have been sent and the TEF must therefore be
full.

Reported-by: Sven Schuchmann &lt;schuchmann@schleissheimer.de&gt;
Closes: https://patch.msgid.link/FR3P281MB155216711EFF900AD9791B7ED9692@FR3P281MB1552.DEUP281.PROD.OUTLOOK.COM
Fixes: b8e0ddd36ce9 ("can: mcp251xfd: tef: prepare to workaround broken TEF FIFO tail index erratum")
Tested-by: Sven Schuchmann &lt;schuchmann@schleissheimer.de&gt;
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20241104-mcp251xfd-fix-length-calculation-v3-1-608b6e7e2197@pengutronix.de
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>can: m_can: m_can_close(): don't call free_irq() for IRQ-less devices</title>
<updated>2024-11-14T12:21:04+00:00</updated>
<author>
<name>Marc Kleine-Budde</name>
<email>mkl@pengutronix.de</email>
</author>
<published>2024-09-30T17:02:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=69d463c4c736fb50450b2c200e8f6c8bf096d583'/>
<id>69d463c4c736fb50450b2c200e8f6c8bf096d583</id>
<content type='text'>
commit e4de81f9e134c78ff7c75a00e43bd819643530d0 upstream.

In commit b382380c0d2d ("can: m_can: Add hrtimer to generate software
interrupt") support for IRQ-less devices was added. Instead of an
interrupt, the interrupt routine is called by a hrtimer-based polling
loop.

That patch forgot to change free_irq() to be only called for devices
with IRQs. Fix this, by calling free_irq() conditionally only if an
IRQ is available for the device (and thus has been requested
previously).

Fixes: b382380c0d2d ("can: m_can: Add hrtimer to generate software interrupt")
Reviewed-by: Simon Horman &lt;horms@kernel.org&gt;
Reviewed-by: Markus Schneider-Pargmann &lt;msp@baylibre.com&gt;
Link: https://patch.msgid.link/20240930-m_can-cleanups-v1-1-001c579cdee4@pengutronix.de
Cc: &lt;stable@vger.kernel.org&gt; # v6.6+
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit e4de81f9e134c78ff7c75a00e43bd819643530d0 upstream.

In commit b382380c0d2d ("can: m_can: Add hrtimer to generate software
interrupt") support for IRQ-less devices was added. Instead of an
interrupt, the interrupt routine is called by a hrtimer-based polling
loop.

That patch forgot to change free_irq() to be only called for devices
with IRQs. Fix this, by calling free_irq() conditionally only if an
IRQ is available for the device (and thus has been requested
previously).

Fixes: b382380c0d2d ("can: m_can: Add hrtimer to generate software interrupt")
Reviewed-by: Simon Horman &lt;horms@kernel.org&gt;
Reviewed-by: Markus Schneider-Pargmann &lt;msp@baylibre.com&gt;
Link: https://patch.msgid.link/20240930-m_can-cleanups-v1-1-001c579cdee4@pengutronix.de
Cc: &lt;stable@vger.kernel.org&gt; # v6.6+
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>can: c_can: fix {rx,tx}_errors statistics</title>
<updated>2024-11-14T12:20:59+00:00</updated>
<author>
<name>Dario Binacchi</name>
<email>dario.binacchi@amarulasolutions.com</email>
</author>
<published>2024-10-14T13:53:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=26473cb9904749341a98f6e75f31cfde462883ae'/>
<id>26473cb9904749341a98f6e75f31cfde462883ae</id>
<content type='text'>
[ Upstream commit 4d6d26537940f3b3e17138987ed9e4a334780bf7 ]

The c_can_handle_bus_err() function was incorrectly incrementing only the
receive error counter, even in cases of bit or acknowledgment errors that
occur during transmission. The patch fixes the issue by incrementing the
appropriate counter based on the type of error.

Fixes: 881ff67ad450 ("can: c_can: Added support for Bosch C_CAN controller")
Signed-off-by: Dario Binacchi &lt;dario.binacchi@amarulasolutions.com&gt;
Link: https://patch.msgid.link/20241014135319.2009782-1-dario.binacchi@amarulasolutions.com
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 4d6d26537940f3b3e17138987ed9e4a334780bf7 ]

The c_can_handle_bus_err() function was incorrectly incrementing only the
receive error counter, even in cases of bit or acknowledgment errors that
occur during transmission. The patch fixes the issue by incrementing the
appropriate counter based on the type of error.

Fixes: 881ff67ad450 ("can: c_can: Added support for Bosch C_CAN controller")
Signed-off-by: Dario Binacchi &lt;dario.binacchi@amarulasolutions.com&gt;
Link: https://patch.msgid.link/20241014135319.2009782-1-dario.binacchi@amarulasolutions.com
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>can: netlink: avoid call to do_set_data_bittiming callback with stale can_priv::ctrlmode</title>
<updated>2024-10-10T10:03:15+00:00</updated>
<author>
<name>Stefan Mätje</name>
<email>stefan.maetje@esd.eu</email>
</author>
<published>2024-08-08T16:42:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b035da50beced97afe03d1324fcd1ccad77b21c6'/>
<id>b035da50beced97afe03d1324fcd1ccad77b21c6</id>
<content type='text'>
[ Upstream commit 2423cc20087ae9a7b7af575aa62304ef67cad7b6 ]

This patch moves the evaluation of data[IFLA_CAN_CTRLMODE] in function
can_changelink in front of the evaluation of data[IFLA_CAN_BITTIMING].

This avoids a call to do_set_data_bittiming providing a stale
can_priv::ctrlmode with a CAN_CTRLMODE_FD flag not matching the
requested state when switching between a CAN Classic and CAN-FD bitrate.

In the same manner the evaluation of data[IFLA_CAN_CTRLMODE] in function
can_validate is also moved in front of the evaluation of
data[IFLA_CAN_BITTIMING].

This is a preparation for patches where the nominal and data bittiming
may have interdependencies on the driver side depending on the
CAN_CTRLMODE_FD flag state.

Signed-off-by: Stefan Mätje &lt;stefan.maetje@esd.eu&gt;
Link: https://patch.msgid.link/20240808164224.213522-1-stefan.maetje@esd.eu
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 2423cc20087ae9a7b7af575aa62304ef67cad7b6 ]

This patch moves the evaluation of data[IFLA_CAN_CTRLMODE] in function
can_changelink in front of the evaluation of data[IFLA_CAN_BITTIMING].

This avoids a call to do_set_data_bittiming providing a stale
can_priv::ctrlmode with a CAN_CTRLMODE_FD flag not matching the
requested state when switching between a CAN Classic and CAN-FD bitrate.

In the same manner the evaluation of data[IFLA_CAN_CTRLMODE] in function
can_validate is also moved in front of the evaluation of
data[IFLA_CAN_BITTIMING].

This is a preparation for patches where the nominal and data bittiming
may have interdependencies on the driver side depending on the
CAN_CTRLMODE_FD flag state.

Signed-off-by: Stefan Mätje &lt;stefan.maetje@esd.eu&gt;
Link: https://patch.msgid.link/20240808164224.213522-1-stefan.maetje@esd.eu
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>can: esd_usb: Remove CAN_CTRLMODE_3_SAMPLES for CAN-USB/3-FD</title>
<updated>2024-10-04T14:38:39+00:00</updated>
<author>
<name>Stefan Mätje</name>
<email>stefan.maetje@esd.eu</email>
</author>
<published>2024-09-04T22:27:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=df3c63c5982d47701a1338f552b4fd11f4875944'/>
<id>df3c63c5982d47701a1338f552b4fd11f4875944</id>
<content type='text'>
commit 75b3189540578f96b4996e4849b6649998f49455 upstream.

Remove the CAN_CTRLMODE_3_SAMPLES announcement for CAN-USB/3-FD devices
because these devices don't support it.

The hardware has a Microchip SAM E70 microcontroller that uses a Bosch
MCAN IP core as CAN FD controller. But this MCAN core doesn't support
triple sampling.

Fixes: 80662d943075 ("can: esd_usb: Add support for esd CAN-USB/3")
Cc: stable@vger.kernel.org
Signed-off-by: Stefan Mätje &lt;stefan.maetje@esd.eu&gt;
Reviewed-by: Vincent Mailhol &lt;mailhol.vincent@wanadoo.fr&gt;
Link: https://patch.msgid.link/20240904222740.2985864-2-stefan.maetje@esd.eu
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 75b3189540578f96b4996e4849b6649998f49455 upstream.

Remove the CAN_CTRLMODE_3_SAMPLES announcement for CAN-USB/3-FD devices
because these devices don't support it.

The hardware has a Microchip SAM E70 microcontroller that uses a Bosch
MCAN IP core as CAN FD controller. But this MCAN core doesn't support
triple sampling.

Fixes: 80662d943075 ("can: esd_usb: Add support for esd CAN-USB/3")
Cc: stable@vger.kernel.org
Signed-off-by: Stefan Mätje &lt;stefan.maetje@esd.eu&gt;
Reviewed-by: Vincent Mailhol &lt;mailhol.vincent@wanadoo.fr&gt;
Link: https://patch.msgid.link/20240904222740.2985864-2-stefan.maetje@esd.eu
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>can: m_can: m_can_close(): stop clocks after device has been shut down</title>
<updated>2024-10-04T14:37:29+00:00</updated>
<author>
<name>Marc Kleine-Budde</name>
<email>mkl@pengutronix.de</email>
</author>
<published>2024-09-09T13:07:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ad089dde9c96bc65cc94f253a41d3dfeaa283341'/>
<id>ad089dde9c96bc65cc94f253a41d3dfeaa283341</id>
<content type='text'>
[ Upstream commit 2c09b50efcad985cf920ca88baa9aa52b1999dcc ]

After calling m_can_stop() an interrupt may be pending or NAPI might
still be executed. This means the driver might still touch registers
of the IP core after the clocks have been disabled. This is not good
practice and might lead to aborts depending on the SoC integration.

To avoid these potential problems, make m_can_close() symmetric to
m_can_open(), i.e. stop the clocks at the end, right before shutting
down the transceiver.

Fixes: e0d1f4816f2a ("can: m_can: add Bosch M_CAN controller support")
Link: https://patch.msgid.link/20240910-can-m_can-fix-ifup-v3-2-6c1720ba45ce@pengutronix.de
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 2c09b50efcad985cf920ca88baa9aa52b1999dcc ]

After calling m_can_stop() an interrupt may be pending or NAPI might
still be executed. This means the driver might still touch registers
of the IP core after the clocks have been disabled. This is not good
practice and might lead to aborts depending on the SoC integration.

To avoid these potential problems, make m_can_close() symmetric to
m_can_open(), i.e. stop the clocks at the end, right before shutting
down the transceiver.

Fixes: e0d1f4816f2a ("can: m_can: add Bosch M_CAN controller support")
Link: https://patch.msgid.link/20240910-can-m_can-fix-ifup-v3-2-6c1720ba45ce@pengutronix.de
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>can: m_can: enable NAPI before enabling interrupts</title>
<updated>2024-10-04T14:37:29+00:00</updated>
<author>
<name>Jake Hamby</name>
<email>Jake.Hamby@Teledyne.com</email>
</author>
<published>2024-09-06T23:19:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6f8840428d191f91adb96d66b30075465a747a83'/>
<id>6f8840428d191f91adb96d66b30075465a747a83</id>
<content type='text'>
[ Upstream commit 801ad2f87b0c6d0c34a75a4efd6bfd3a2d9f9298 ]

If an interrupt (RX-complete or error flag) is set when bringing up
the CAN device, e.g. due to CAN bus traffic before initializing the
device, when m_can_start() is called and interrupts are enabled,
m_can_isr() is called immediately, which disables all CAN interrupts
and calls napi_schedule().

Because napi_enable() isn't called until later in m_can_open(), the
call to napi_schedule() never schedules the m_can_poll() callback and
the device is left with interrupts disabled and can't receive any CAN
packets until rebooted.

This can be verified by running "cansend" from another device before
setting the bitrate and calling "ip link set up can0" on the test
device. Adding debug lines to m_can_isr() shows it's called with flags
(IR_EP | IR_EW | IR_CRCE), which calls m_can_disable_all_interrupts()
and napi_schedule(), and then m_can_poll() is never called.

Move the call to napi_enable() above the call to m_can_start() to
enable any initial interrupt flags to be handled by m_can_poll() so
that interrupts are reenabled. Add a call to napi_disable() in the
error handling section of m_can_open(), to handle the case where later
functions return errors.

Also, in m_can_close(), move the call to napi_disable() below the call
to m_can_stop() to ensure all interrupts are handled when bringing
down the device. This race condition is much less likely to occur.

Tested on a Microchip SAMA7G54 MPU. The fix should be applicable to
any SoC with a Bosch M_CAN controller.

Signed-off-by: Jake Hamby &lt;Jake.Hamby@Teledyne.com&gt;
Fixes: e0d1f4816f2a ("can: m_can: add Bosch M_CAN controller support")
Link: https://patch.msgid.link/20240910-can-m_can-fix-ifup-v3-1-6c1720ba45ce@pengutronix.de
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 801ad2f87b0c6d0c34a75a4efd6bfd3a2d9f9298 ]

If an interrupt (RX-complete or error flag) is set when bringing up
the CAN device, e.g. due to CAN bus traffic before initializing the
device, when m_can_start() is called and interrupts are enabled,
m_can_isr() is called immediately, which disables all CAN interrupts
and calls napi_schedule().

Because napi_enable() isn't called until later in m_can_open(), the
call to napi_schedule() never schedules the m_can_poll() callback and
the device is left with interrupts disabled and can't receive any CAN
packets until rebooted.

This can be verified by running "cansend" from another device before
setting the bitrate and calling "ip link set up can0" on the test
device. Adding debug lines to m_can_isr() shows it's called with flags
(IR_EP | IR_EW | IR_CRCE), which calls m_can_disable_all_interrupts()
and napi_schedule(), and then m_can_poll() is never called.

Move the call to napi_enable() above the call to m_can_start() to
enable any initial interrupt flags to be handled by m_can_poll() so
that interrupts are reenabled. Add a call to napi_disable() in the
error handling section of m_can_open(), to handle the case where later
functions return errors.

Also, in m_can_close(), move the call to napi_disable() below the call
to m_can_stop() to ensure all interrupts are handled when bringing
down the device. This race condition is much less likely to occur.

Tested on a Microchip SAMA7G54 MPU. The fix should be applicable to
any SoC with a Bosch M_CAN controller.

Signed-off-by: Jake Hamby &lt;Jake.Hamby@Teledyne.com&gt;
Fixes: e0d1f4816f2a ("can: m_can: add Bosch M_CAN controller support")
Link: https://patch.msgid.link/20240910-can-m_can-fix-ifup-v3-1-6c1720ba45ce@pengutronix.de
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>can: kvaser_pciefd: Use a single write when releasing RX buffers</title>
<updated>2024-08-30T21:45:55+00:00</updated>
<author>
<name>Martin Jocic</name>
<email>martin.jocic@kvaser.com</email>
</author>
<published>2024-08-30T15:31:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=dd885d90c047dbdd2773c1d33954cbd8747d81e2'/>
<id>dd885d90c047dbdd2773c1d33954cbd8747d81e2</id>
<content type='text'>
Kvaser's PCIe cards uses the KCAN FPGA IP block which has dual 4K
buffers for incoming messages shared by all (currently up to eight)
channels. While the driver processes messages in one buffer, new
incoming messages are stored in the other and so on.

The design of KCAN is such that a buffer must be fully read and then
released. Releasing a buffer will make the FPGA switch buffers. If the
other buffer contains at least one incoming message the FPGA will also
instantly issue a new interrupt, if not the interrupt will be issued
after receiving the first new message.

With IRQx interrupts, it takes a little time for the interrupt to
happen, enough for any previous ISR call to do it's business and
return, but MSI interrupts are way faster so this time is reduced to
almost nothing.

So with MSI, releasing the buffer HAS to be the very last action of
the ISR before returning, otherwise the new interrupt might be
"masked" by the kernel because the previous ISR call hasn't returned.
And the interrupts are edge-triggered so we cannot loose one, or the
ping-pong reading process will stop.

This is why this patch modifies the driver to use a single write to
the SRB_CMD register before returning.

Signed-off-by: Martin Jocic &lt;martin.jocic@kvaser.com&gt;
Reviewed-by: Vincent Mailhol &lt;mailhol.vincent@wanadoo.fr&gt;
Link: https://patch.msgid.link/20240830153113.2081440-1-martin.jocic@kvaser.com
Fixes: 26ad340e582d ("can: kvaser_pciefd: Add driver for Kvaser PCIEcan devices")
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Kvaser's PCIe cards uses the KCAN FPGA IP block which has dual 4K
buffers for incoming messages shared by all (currently up to eight)
channels. While the driver processes messages in one buffer, new
incoming messages are stored in the other and so on.

The design of KCAN is such that a buffer must be fully read and then
released. Releasing a buffer will make the FPGA switch buffers. If the
other buffer contains at least one incoming message the FPGA will also
instantly issue a new interrupt, if not the interrupt will be issued
after receiving the first new message.

With IRQx interrupts, it takes a little time for the interrupt to
happen, enough for any previous ISR call to do it's business and
return, but MSI interrupts are way faster so this time is reduced to
almost nothing.

So with MSI, releasing the buffer HAS to be the very last action of
the ISR before returning, otherwise the new interrupt might be
"masked" by the kernel because the previous ISR call hasn't returned.
And the interrupts are edge-triggered so we cannot loose one, or the
ping-pong reading process will stop.

This is why this patch modifies the driver to use a single write to
the SRB_CMD register before returning.

Signed-off-by: Martin Jocic &lt;martin.jocic@kvaser.com&gt;
Reviewed-by: Vincent Mailhol &lt;mailhol.vincent@wanadoo.fr&gt;
Link: https://patch.msgid.link/20240830153113.2081440-1-martin.jocic@kvaser.com
Fixes: 26ad340e582d ("can: kvaser_pciefd: Add driver for Kvaser PCIEcan devices")
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
</pre>
</div>
</content>
</entry>
</feed>
