linux-stable.git/drivers/spi, branch v4.4.205

spi: omap2-mcspi: Fix DMA and FIFO event trigger size mismatch

2019-11-28T17:26:11+00:00

[ Upstream commit baf8b9f8d260c55a86405f70a384c29cda888476 ]

Commit b682cffa3ac6 ("spi: omap2-mcspi: Set FIFO DMA trigger level to word length")
broke SPI transfers where bits_per_word != 8. This is because of
mimsatch between McSPI FIFO level event trigger size (SPI word length) and
DMA request size(word length * maxburst). This leads to data
corruption, lockup and errors like:

	spi1.0: EOW timed out

Fix this by setting DMA maxburst size to 1 so that
McSPI FIFO level event trigger size matches DMA request size.

Fixes: b682cffa3ac6 ("spi: omap2-mcspi: Set FIFO DMA trigger level to word length")
Cc: stable@vger.kernel.org
Reported-by: David Lechner 
Tested-by: David Lechner 
Signed-off-by: Vignesh R 
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

spi: omap2-mcspi: Set FIFO DMA trigger level to word length

2019-11-28T17:25:47+00:00

[ Upstream commit b682cffa3ac6d9d9e16e9b413c45caee3b391fab ]

McSPI has 32 byte FIFO in Transmit-Receive mode. Current code tries to
configuration FIFO watermark level for DMA trigger to be GCD of transfer
length and max FIFO size which would mean trigger level may be set to 32
for transmit-receive mode if length is aligned. This does not work in
case of SPI slave mode where FIFO always needs to have data ready
whenever master starts the clock. With DMA trigger size of 32 there will
be a small window during slave TX where DMA is still putting data into
FIFO but master would have started clock for next byte, resulting in
shifting out of stale data. Similarly, on Slave RX side there may be RX
FIFO overflow
Fix this by setting FIFO watermark for DMA trigger to word
length. This means DMA is triggered as soon as FIFO has space for word
length bytes and DMA would make sure FIFO is almost always full
therefore improving FIFO occupancy in both master and slave mode.

Signed-off-by: Vignesh R 
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

spi: sh-msiof: fix deferred probing

2019-11-28T17:25:37+00:00

[ Upstream commit f34c6e6257aa477cdfe7e9bbbecd3c5648ecda69 ]

Since commit 9ec36cafe43b ("of/irq: do irq resolution in platform_get_irq")
platform_get_irq() can return -EPROBE_DEFER. However, the driver overrides
an error returned by that function with -ENOENT which breaks the deferred
probing. Propagate upstream an error code returned by platform_get_irq()
and remove the bogus "platform" from the error message, while at it...

Fixes: 9ec36cafe43b ("of/irq: do irq resolution in platform_get_irq")
Signed-off-by: Sergei Shtylyov 
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

spi: rockchip: initialize dma_slave_config properly

2019-11-25T14:54:51+00:00

[ Upstream commit dd8fd2cbc73f8650f651da71fc61a6e4f30c1566 ]

The rxconf and txconf structs are allocated on the
stack, so make sure we zero them before filling out
the relevant fields.

Signed-off-by: Huibin Hong 
Signed-off-by: Emil Renner Berthing 
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

spi: spidev: Fix OF tree warning logic

2019-11-25T14:54:50+00:00

[ Upstream commit 605b3bec73cbd74b4ac937b580cd0b47d1300484 ]

spidev will make a big fuss if a device tree node binds a device by
using "spidev" as the node's compatible property.

However, the logic for this isn't looking for "spidev" in the
compatible, but rather checking that the device is NOT compatible with
spidev's list of devices.

This causes a false positive if a device not named "rohm,dh2228fv", etc.
binds to spidev, even if a means other than putting "spidev" in the
device tree was used.  E.g., the sysfs driver_override attribute.

Signed-off-by: Trent Piepho 
Reviewed-by: Jan KundrÃ¡t 
Tested-by: Jan KundrÃ¡t 
Reviewed-by: Geert Uytterhoeven 
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

spi: bcm2835aux: fix corruptions for longer spi transfers

2019-09-10T09:29:50+00:00

[ Upstream commit 73b114ee7db1750c0b535199fae383b109bd61d0 ]

On long running tests with a mcp2517fd can controller it showed that
on rare occations the data read shows corruptions for longer spi transfers.

Example of a 22 byte transfer:

expected (as captured on logic analyzer):
FF FF 78 00 00 00 08 06 00 00 91 20 77 56 84 85 86 87 88 89 8a 8b

read by the driver:
FF FF 78 00 00 00 08 06 00 00 91 20 77 56 84 88 89 8a 00 00 8b 9b

To fix this use BCM2835_AUX_SPI_STAT_RX_LVL to determine when we may
read data from the fifo reliably without any corruption.

Surprisingly the only values ever empirically read in
BCM2835_AUX_SPI_STAT_RX_LVL are 0x00, 0x10, 0x20 and 0x30.
So whenever the mask is not 0 we can read from the fifo in a safe manner.

The patch has now been tested intensively and we are no longer
able to reproduce the "RX" issue any longer.

Fixes: 1ea29b39f4c812ec ("spi: bcm2835aux: add bcm2835 auxiliary spi device...")
Reported-by: Hubert Denkmair 
Signed-off-by: Martin Sperl 
Acked-by: Stefan Wahren 
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

spi: bcm2835aux: remove dangerous uncontrolled read of fifo

2019-09-10T09:29:49+00:00

[ Upstream commit c7de8500fd8ecbb544846dd5f11dca578c3777e1 ]

This read of the fifo is a potential candidate for a race condition
as the spi transfer is not necessarily finished and so can lead to
an early read of the fifo that still misses data.

So it has been removed.

Fixes: 1ea29b39f4c812ec ("spi: bcm2835aux: add bcm2835 auxiliary spi device...")
Suggested-by: Hubert Denkmair 
Signed-off-by: Martin Sperl 
Acked-by: Stefan Wahren 
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

spi: bcm2835aux: unifying code between polling and interrupt driven code

2019-09-10T09:29:49+00:00

[ Upstream commit 7188a6f0eee3f1fae5d826cfc6d569657ff950ec ]

Sharing more code between polling and interrupt-driven mode.

Signed-off-by: Martin Sperl 
Acked-by: Stefan Wahren 
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

spi: bcm2835aux: ensure interrupts are enabled for shared handler

2019-09-10T09:29:49+00:00

[ Upstream commit bc519d9574618e47a0c788000fb78da95e18d953 ]

The BCM2835 AUX SPI has a shared interrupt line (with AUX UART).
Downstream fixes this with an AUX irqchip to demux the IRQ sources and a
DT change which breaks compatibility with older kernels. The AUX irqchip
was already rejected for upstream[1] and the DT change would break
working systems if the DTB is updated to a newer one. The latter issue
was brought to my attention by Alex Graf.

The root cause however is a bug in the shared handler. Shared handlers
must check that interrupts are actually enabled before servicing the
interrupt. Add a check that the TXEMPTY or IDLE interrupts are enabled.

[1] https://patchwork.kernel.org/patch/9781221/

Cc: Alexander Graf 
Cc: Marc Zyngier 
Cc: Mark Brown 
Cc: Eric Anholt 
Cc: Stefan Wahren 
Cc: Florian Fainelli 
Cc: Ray Jui 
Cc: Scott Branden 
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: linux-spi@vger.kernel.org
Cc: linux-rpi-kernel@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Rob Herring 
Reviewed-by: Eric Anholt 
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

spi: bcm2835: Fix 3-wire mode if DMA is enabled

2019-08-11T10:20:47+00:00

commit 8d8bef50365847134b51c1ec46786bc2873e4e47 upstream.

Commit 6935224da248 ("spi: bcm2835: enable support of 3-wire mode")
added 3-wire support to the BCM2835 SPI driver by setting the REN bit
(Read Enable) in the CS register when receiving data.  The REN bit puts
the transmitter in high-impedance state.  The driver recognizes that
data is to be received by checking whether the rx_buf of a transfer is
non-NULL.

Commit 3ecd37edaa2a ("spi: bcm2835: enable dma modes for transfers
meeting certain conditions") subsequently broke 3-wire support because
it set the SPI_MASTER_MUST_RX flag which causes spi_map_msg() to replace
rx_buf with a dummy buffer if it is NULL.  As a result, rx_buf is
*always* non-NULL if DMA is enabled.

Reinstate 3-wire support by not only checking whether rx_buf is non-NULL,
but also checking that it is not the dummy buffer.

Fixes: 3ecd37edaa2a ("spi: bcm2835: enable dma modes for transfers meeting certain conditions")
Reported-by: Nuno Sá 
Signed-off-by: Lukas Wunner 
Cc: stable@vger.kernel.org # v4.2+
Cc: Martin Sperl 
Acked-by: Stefan Wahren 
Link: https://lore.kernel.org/r/328318841455e505370ef8ecad97b646c033dc8a.1562148527.git.lukas@wunner.de
Signed-off-by: Mark Brown 
Signed-off-by: Greg Kroah-Hartman