linux-stable.git/drivers/spi, branch v4.4.201

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

spi: bitbang: Fix NULL pointer dereference in spi_unregister_master

2019-07-10T07:56:39+00:00

[ Upstream commit 5caaf29af5ca82d5da8bc1d0ad07d9e664ccf1d8 ]

If spi_register_master fails in spi_bitbang_start
because device_add failure, We should return the
error code other than 0, otherwise calling
spi_bitbang_stop may trigger NULL pointer dereference
like this:

BUG: KASAN: null-ptr-deref in __list_del_entry_valid+0x45/0xd0
Read of size 8 at addr 0000000000000000 by task syz-executor.0/3661

CPU: 0 PID: 3661 Comm: syz-executor.0 Not tainted 5.1.0+ #28
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
Call Trace:
 dump_stack+0xa9/0x10e
 ? __list_del_entry_valid+0x45/0xd0
 ? __list_del_entry_valid+0x45/0xd0
 __kasan_report+0x171/0x18d
 ? __list_del_entry_valid+0x45/0xd0
 kasan_report+0xe/0x20
 __list_del_entry_valid+0x45/0xd0
 spi_unregister_controller+0x99/0x1b0
 spi_lm70llp_attach+0x3ae/0x4b0 [spi_lm70llp]
 ? 0xffffffffc1128000
 ? klist_next+0x131/0x1e0
 ? driver_detach+0x40/0x40 [parport]
 port_check+0x3b/0x50 [parport]
 bus_for_each_dev+0x115/0x180
 ? subsys_dev_iter_exit+0x20/0x20
 __parport_register_driver+0x1f0/0x210 [parport]
 ? 0xffffffffc1150000
 do_one_initcall+0xb9/0x3b5
 ? perf_trace_initcall_level+0x270/0x270
 ? kasan_unpoison_shadow+0x30/0x40
 ? kasan_unpoison_shadow+0x30/0x40
 do_init_module+0xe0/0x330
 load_module+0x38eb/0x4270
 ? module_frob_arch_sections+0x20/0x20
 ? kernel_read_file+0x188/0x3f0
 ? find_held_lock+0x6d/0xd0
 ? fput_many+0x1a/0xe0
 ? __do_sys_finit_module+0x162/0x190
 __do_sys_finit_module+0x162/0x190
 ? __ia32_sys_init_module+0x40/0x40
 ? __mutex_unlock_slowpath+0xb4/0x3f0
 ? wait_for_completion+0x240/0x240
 ? vfs_write+0x160/0x2a0
 ? lockdep_hardirqs_off+0xb5/0x100
 ? mark_held_locks+0x1a/0x90
 ? do_syscall_64+0x14/0x2a0
 do_syscall_64+0x72/0x2a0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Reported-by: Hulk Robot 
Fixes: 702a4879ec33 ("spi: bitbang: Let spi_bitbang_start() take a reference to master")
Signed-off-by: YueHaibing 
Reviewed-by: Geert Uytterhoeven 
Reviewed-by: Axel Lin 
Reviewed-by: Mukesh Ojha 
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

dmaengine: idma64: Use actual device for DMA transfers

2019-06-22T06:18:21+00:00

[ Upstream commit 5ba846b1ee0792f5a596b9b0b86d6e8cdebfab06 ]

Intel IOMMU, when enabled, tries to find the domain of the device,
assuming it's a PCI one, during DMA operations, such as mapping or
unmapping. Since we are splitting the actual PCI device to couple of
children via MFD framework (see drivers/mfd/intel-lpss.c for details),
the DMA device appears to be a platform one, and thus not an actual one
that performs DMA. In a such situation IOMMU can't find or allocate
a proper domain for its operations. As a result, all DMA operations are
failed.

In order to fix this, supply parent of the platform device
to the DMA engine framework and fix filter functions accordingly.

We may rely on the fact that parent is a real PCI device, because no
other configuration is present in the wild.

Signed-off-by: Andy Shevchenko 
Acked-by: Mark Brown 
Acked-by: Greg Kroah-Hartman  [for tty parts]
Signed-off-by: Vinod Koul 
Signed-off-by: Sasha Levin

spi: Fix zero length xfer bug

2019-06-11T10:24:06+00:00

[ Upstream commit 5442dcaa0d90fc376bdfc179a018931a8f43dea4 ]

This fixes a bug for messages containing both zero length and
unidirectional xfers.

The function spi_map_msg will allocate dummy tx and/or rx buffers
for use with unidirectional transfers when the hardware can only do
a bidirectional transfer.  That dummy buffer will be used in place
of a NULL buffer even when the xfer length is 0.

Then in the function __spi_map_msg, if he hardware can dma,
the zero length xfer will have spi_map_buf called on the dummy
buffer.

Eventually, __sg_alloc_table is called and returns -EINVAL
because nents == 0.

This fix prevents the error by not using the dummy buffer when
the xfer length is zero.

Signed-off-by: Chris Lesiak 
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

spi: rspi: Fix sequencer reset during initialization

2019-06-11T10:24:06+00:00

[ Upstream commit 26843bb128590edd7eba1ad7ce22e4b9f1066ce3 ]

While the sequencer is reset after each SPI message since commit
880c6d114fd79a69 ("spi: rspi: Add support for Quad and Dual SPI
Transfers on QSPI"), it was never reset for the first message, thus
relying on reset state or bootloader settings.

Fix this by initializing it explicitly during configuration.

Fixes: 0b2182ddac4b8837 ("spi: add support for Renesas RSPI")
Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

spi : spi-topcliff-pch: Fix to handle empty DMA buffers

2019-06-11T10:24:05+00:00

[ Upstream commit f37d8e67f39e6d3eaf4cc5471e8a3d21209843c6 ]

pch_alloc_dma_buf allocated tx, rx DMA buffers which can fail. Further,
these buffers are used without a check. The patch checks for these
failures and sends the error upstream.

Signed-off-by: Aditya Pakki 
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin