Commit Graph

4122 Commits

Author SHA1 Message Date
Linus Torvalds
0051db8218 spi: Updates for v4.21
The main thing this release has been a lot of work on the integration
 with SPI NOR flashes, there's been some specific support for a while for
 controller features designed to make them perform better but it's not
 worked out as well as hoped so the interface has been redesigned in a
 way that will hopefully do better - it's already been adopted by a
 number of additional controllers so things are looking good.  Otherwise
 most of the work has been driver specific:
 
  - Support for better integration with NOR flashes from Boris Brezillon
    and Yogesh Narayan Gaur plus usage of it in several drivers.
  - A big cleanup of the Rockchip driver from Emil Renner Berthing.
  - Lots of performance improvements for bcm2835 from Lukas Wunner.
  - Slave mode support for pxa2xx from Lubomir Rintel.
  - Support for Macronix MXIC, Mediatek MT7629 and MT8183, NPCM PSPI,
    and Renesas r8a77470.
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Merge tag 'spi-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi updates from Mark Brown:
 "The main thing this release has been a lot of work on the integration
  with SPI NOR flashes, there's been some specific support for a while
  for controller features designed to make them perform better but it's
  not worked out as well as hoped so the interface has been redesigned
  in a way that will hopefully do better - it's already been adopted by
  a number of additional controllers so things are looking good.

  Otherwise most of the work has been driver specific:

   - Support for better integration with NOR flashes from Boris
     Brezillon and Yogesh Narayan Gaur plus usage of it in several
     drivers.

   - A big cleanup of the Rockchip driver from Emil Renner Berthing.

   - Lots of performance improvements for bcm2835 from Lukas Wunner.

   - Slave mode support for pxa2xx from Lubomir Rintel.

   - Support for Macronix MXIC, Mediatek MT7629 and MT8183, NPCM PSPI,
     and Renesas r8a77470"

* tag 'spi-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (90 commits)
  spi: sh-msiof: Reduce the number of times write to and perform the transmission from FIFO
  spi: sh-msiof: Add r8a774c0 support
  doc: lpspi: Document DT bindings for LPSPI slave mode
  spi: lpspi: Let watermark change with send data length
  spi: lpspi: Add slave mode support
  spi: lpspi: Replace all "master" with "controller"
  spi: imx: drop useless member speed_hz from driver data struct
  spi: imx: rename config callback and add useful parameters
  spi: imx: style fixes
  spi: imx: mx51-ecspi: Move some initialisation to prepare_message hook.
  spi: imx: add a device specific prepare_message callback
  mtd: atmel-quadspi: disallow building on ebsa110
  spi: Update NPCM PSPI controller documentation
  spi: npcm: Modify pspi send function
  spi: Use of_node_name_eq for node name comparisons
  spi: dw-mmio: add ACPI support
  spi: bcm2835: Synchronize with callback on DMA termination
  spi: bcm2835: Speed up FIFO access if fill level is known
  spi: bcm2835: Polish transfer of DMA prologue
  spi: spi-mem: add support for octal mode I/O data transfer
  ...
2018-12-25 14:43:54 -08:00
Mark Brown
74ff666bd7
Merge remote-tracking branches 'spi/topic/mem' and 'spi/topic/mtd' into spi-next 2018-12-20 16:01:30 +00:00
Hoan Nguyen An
916d9802e4
spi: sh-msiof: Reduce the number of times write to and perform the transmission from FIFO
The current state of the spi-sh-msiof, in master transfer mode: if t-> bits_per_word <= 8,
if the data length is divisible by 4 ((len & 3) = 0), the length of each word will be 32 bits
In case of data length can not be divisible by 4 ((len & 3) != 0), always set each word to be
8 bits, this will increase the number of times that write to FIFO, increasing the number of
times it should be transmitted. Assume that the number of bytes of data length more than 64 bytes,
each transmission will write 64 times into the TFDR then transmit, a maximum one-time
transmission will transmit 64 bytes if each word is 8 bits long.

Switch to setting if t->bits_per_word <= 8, the word length will be 32 bits although the data
length is not divisible by 4, then if leftover, will transmit the balance and the length of each
words is 1 byte. The maximum each can transmit up to 64 x 4 (Data Size = 32 bits (4 bytes)) = 256 bytes.
TMDR2 : Bits 28 to 24  BITLEN1[4:0] Data Size (8 to 32 bits)
        Bits 23 to 16  WDLEN1[7:0]  Word Count (1 to 64 words)

Signed-off-by: Hoan Nguyen An <na-hoan@jinso.co.jp>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-20 14:56:11 +00:00
Clark Wang
cf86874bb9
spi: lpspi: Let watermark change with send data length
Configure watermark to change with the length of the sent data.
Support LPSPI sending message shorter than tx/rxfifosize.

Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-13 11:57:28 +00:00
Clark Wang
bcd87317aa
spi: lpspi: Add slave mode support
Add slave mode support to the fsl-lpspi driver, only in PIO mode.

For now, there are some limitations for slave mode transmission:
1. The stale data in RXFIFO will be dropped when the Slave does any new
   transfer.
2. One transfer can be finished only after all transfer->len data been
   transferred to master device
3. Slave device only accepts transfer->len data. Any data longer than
   this from master device will be dropped. Any data shorter than this
   from master will cause LPSPI to stuck due to mentioned limitation 2.
4. Only PIO transfer is supported in Slave Mode.

Wire connection:
GND, SCK, MISO(to MISO of slave), MOSI(to MOSI of slave), SCS

Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-13 11:57:14 +00:00
Clark Wang
07d7155749
spi: lpspi: Replace all "master" with "controller"
In order to enable the slave mode and make the code more readable,
replace all related structure names and object names which is
named "master" with "controller".

Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-13 11:56:28 +00:00
Mark Brown
e6202e8249
Merge branch 'for-linus' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator into regulator-4.21 2018-12-11 20:44:49 +00:00
Uwe Kleine-König
3f75720d0e
spi: imx: drop useless member speed_hz from driver data struct
The driver data's member variable just caches the transfer's speed_hz
member. All users of the former now have access directly to the latter.
So fix them to use the uncached value and remove the cache.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-11 12:00:18 +00:00
Uwe Kleine-König
1d374703fb
spi: imx: rename config callback and add useful parameters
The config callback is called once per transfer while some things can (and
should) be done on a per message manner. To have unambiguous naming in the
end include "transfer" in the callback's name and rename the
implementations accordingly. Also pass the driver struct and transfer
which allows further simplifications in the following patch.

There is no change in behavior intended here.

Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-11 12:00:03 +00:00
Uwe Kleine-König
30d6714223
spi: imx: style fixes
This change fixes some random style issues that I noticed while debugging
the driver: Remove some double spaces, use tabs for indention instead
of spaces if possible, fix comment style.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-11 11:59:48 +00:00
Uwe Kleine-König
00b80ac935
spi: imx: mx51-ecspi: Move some initialisation to prepare_message hook.
The relevant difference between prepare_message and config is that the
former is run before the CS signal is asserted. So the polarity of the
CLK line must be configured in prepare_message as an edge generated by
config might already result in a latch of the MOSI line.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-11 11:59:33 +00:00
Uwe Kleine-König
e697271c4e
spi: imx: add a device specific prepare_message callback
This is just preparatory work which allows to move some initialisation
that currently is done in the per transfer hook .config to an earlier
point in time in the next few patches. There is no change in behaviour
introduced by this patch.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-11 11:57:13 +00:00
Arnd Bergmann
2a9d92fb3a
mtd: atmel-quadspi: disallow building on ebsa110
I ran into a link-time error with the atmel-quadspi driver on the
EBSA110 platform:

drivers/mtd/built-in.o: In function `atmel_qspi_run_command':
:(.text+0x1ee3c): undefined reference to `_memcpy_toio'
:(.text+0x1ee48): undefined reference to `_memcpy_fromio'

The problem is that _memcpy_toio/_memcpy_fromio are not available on
that platform, and we have to prevent building the driver there.

In case we want to backport this to older kernels: between linux-4.8
and linux-4.20, the Kconfig entry was in drivers/mtd/spi-nor/Kconfig
but had the same problem.

Link: https://lore.kernel.org/patchwork/patch/812860/
Fixes: 161aaab8a0 ("mtd: atmel-quadspi: add driver for Atmel QSPI controller")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
2018-12-11 01:15:11 +00:00
Tomer Maimon
1fa33be36c
spi: npcm: Modify pspi send function
Align pspi send function code with the recieve function
code, Also simplify the code a bit with early return.

Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-06 20:23:26 +00:00
Rob Herring
194276b073
spi: Use of_node_name_eq for node name comparisons
Convert string compares of DT node names to use of_node_name_eq helper
instead. This removes direct access to the node name pointer.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-06 20:15:43 +00:00
Mark Brown
ae218f7847
Merge branch 'topic/3wire-gpio' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-4.21 mode conflict 2018-12-04 17:31:49 +00:00
Jay Fang
32215a6c6b
spi: dw-mmio: add ACPI support
The Hisilicon Hip08 platform, that uses ACPI, has this controller.
Let's add ACPI support for DW SPI MMIO-based host.

The ACPI ID used is "HISI0173" for the Designware SPI controller of
Hisilicon Hip08 platform.

Signed-off-by: Jay Fang <f.fangjian@huawei.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-04 17:24:57 +00:00
Lukas Wunner
2527704d84
spi: bcm2835: Synchronize with callback on DMA termination
Commit b36f09c3c4 ("dmaengine: Add transfer termination
synchronization support") deprecated dmaengine_terminate_all() in favor
of dmaengine_terminate_sync() and dmaengine_terminate_async() to avoid
freeing resources used by the DMA callback before its execution has
concluded.

Commit de92436ac4 ("dmaengine: bcm2835-dma: Use vchan_terminate_vdesc()
instead of desc_free") amended the BCM2835 DMA driver with an
implementation of ->device_synchronize(), which is a prerequisite for
dmaengine_terminate_sync().  Thus, clients of the DMA driver (such as
the BCM2835 SPI driver) may now be converted to the new API.

It is generally desirable to use the _sync() variant except in atomic
context.  There is only a single occurrence where the BCM2835 SPI driver
calls dmaengine_terminate_all() in atomic context and that is in
bcm2835_spi_dma_done() (the RX DMA channel's callback) to terminate the
TX DMA channel.  The TX DMA channel doesn't have a callback (yet), hence
it is safe to use the _async() variant there.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-04 16:51:55 +00:00
Lukas Wunner
2e0733bc5a
spi: bcm2835: Speed up FIFO access if fill level is known
The RX and TX FIFO of the BCM2835 SPI master each accommodate 64 bytes
(16 32-bit dwords).  The CS register provides hints on their fill level:

   "Bit 19  RXR - RX FIFO needs Reading ([¾] full)
    0 = RX FIFO is less than [¾] full (or not active TA = 0).
    1 = RX FIFO is [¾] or more full. Cleared by reading sufficient
        data from the RX FIFO or setting TA to 0."

   "Bit 16  DONE - Transfer Done
    0 = Transfer is in progress (or not active TA = 0).
    1 = Transfer is complete. Cleared by writing more data to the
        TX FIFO or setting TA to 0."

   "If DONE is set [...], write up to 16 [dwords] to SPI_FIFO. [...]
    If RXR is set read 12 [dwords] data from SPI_FIFO."

   [Source: Pages 153, 154 and 158 of
    https://www.raspberrypi.org/app/uploads/2012/02/BCM2835-ARM-Peripherals.pdf
    Note: The spec is missing the "¾" character, presumably due to
    copy-pasting from a different charset.  It also incorrectly
    refers to 16 and 12 "bytes" instead of 32-bit dwords.]

In short, the RXR bit indicates that 48 bytes can be read and the DONE
bit indicates 64 bytes can be written.  Leverage this knowledge to read
or write bytes blindly to the FIFO, without polling whether data can be
read or free space is available to write.  Moreover, when a transfer is
starting, the TX FIFO is known to be empty, likewise allowing a blind
write of 64 bytes.

This cuts the number of bus accesses in half if the fill level is known.
Also, the (posted) write accesses can be pipelined on the AXI bus since
they are no longer interleaved with (non-posted) reads.

bcm2835_spi_transfer_one_poll() switches to interrupt mode when a time
limit is exceeded by calling bcm2835_spi_transfer_one_irq().  The TX
FIFO may contain data in this case, but is known to be empty when the
function is called from bcm2835_spi_transfer_one().  Hence only blindly
fill the TX FIFO in the latter case but not the former.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Tested-by: Eric Anholt <eric@anholt.net>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-04 16:51:41 +00:00
Lukas Wunner
b31a9299bc
spi: bcm2835: Polish transfer of DMA prologue
Commit 3bd7f6589f ("spi: bcm2835: Overcome sglist entry length
limitation") was unfortunately merged even though submission of a
refined version was imminent.  Apply those refinements as an amendment:

* Drop no longer needed #include <asm/page.h>.  The lines requiring
  its inclusion were removed by the commit.

* Change type of tx_spillover flag from bool to unsigned int for
  consistency with dma_pending flag and pursuant to Linus' dictum:
  https://lkml.org/lkml/2017/11/21/384

* In bcm2835_rd_fifo_count() do not check for bs->rx_buf != NULL.
  The function will never be called if that's the case.

* Amend kerneldoc of bcm2835_wait_tx_fifo_empty() to prevent its use in
  situations where the function might spin forever.  (In response to a
  review comment by Stefan Wahren.)

* Sync only the cacheline containing the RX prologue back to memory,
  not the full first sglist entry.

* Use sg_dma_address() and sg_dma_len() instead of referencing the
  sglist entry members directly.  Seems to be the more common syntax in
  the tree, even for lvalues.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-04 16:51:12 +00:00
Yogesh Narayan Gaur
b12a084c87
spi: spi-mem: add support for octal mode I/O data transfer
Add support for octal mode I/O data transfer in spi-mem framework.

Signed-off-by: Yogesh Gaur <yogeshnarayan.gaur@nxp.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-03 17:20:14 +00:00
Yogesh Narayan Gaur
6b03061f88
spi: add support for octal mode I/O data transfer
Add flags for Octal mode I/O data transfer
Required for the SPI controller which can do the data transfer (TX/RX)
on 8 data lines e.g. NXP FlexSPI controller.
 SPI_TX_OCTAL: transmit with 8 wires
 SPI_RX_OCTAL: receive with 8 wires

Signed-off-by: Yogesh Gaur <yogeshnarayan.gaur@nxp.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-03 17:14:53 +00:00
Randy Dunlap
c2b142cc39
spi: fix spi-at91-usart.c build errors when PINCTRL is not set
Fix build errors when CONFIG_PINCTRL is not enabled.
The header file <linux/pinctrl/consumer.h> handles both CONFIG_PINCTRL
enabled and disabled cases.

  CC [M]  drivers/spi/spi-at91-usart.o
../drivers/spi/spi-at91-usart.c: In function 'at91_usart_spi_runtime_suspend':
../drivers/spi/spi-at91-usart.c:409:2: error: implicit declaration of function 'pinctrl_pm_select_sleep_state' [-Werror=implicit-function-declaration]
  pinctrl_pm_select_sleep_state(dev);
../drivers/spi/spi-at91-usart.c: In function 'at91_usart_spi_runtime_resume':
../drivers/spi/spi-at91-usart.c:419:2: error: implicit declaration of function 'pinctrl_pm_select_default_state' [-Werror=implicit-function-declaration]
  pinctrl_pm_select_default_state(dev);

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Radu Pirea <radu.pirea@microchip.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: linux-spi@vger.kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-03 11:57:14 +00:00
Mark Brown
787f4889a6
spi: Fix formatting of header block
Make everything look intentional by having a C++ comment for the whole
block, not just the SPDX line.

Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-29 16:24:37 +00:00
Mark Brown
5651248697
Merge branch 'for-4.20' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-4.21 2018-11-29 16:23:39 +00:00
Lukas Wunner
29bdedfd9c
spi: bcm2835: Unbreak the build of esoteric configs
Commit e82b0b3828 ("spi: bcm2835: Fix race on DMA termination") broke
the build with COMPILE_TEST=y on arches whose cmpxchg() requires 32-bit
operands (xtensa, older arm ISAs).

Fix by changing the dma_pending flag's type from bool to unsigned int.

Fixes: e82b0b3828 ("spi: bcm2835: Fix race on DMA termination")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
2018-11-29 16:02:01 +00:00
Linus Torvalds
5b26f7180c spi: Fixes for v4.20
A few driver specific fixes here, nothing big or that stands out for
 anyone other than the driver users.
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Merge tag 'spi-fix-v4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi fixes from Mark Brown:
 "A few driver specific fixes here, nothing big or that stands out for
  anyone other than the driver users.

  The omap2-mcspi fix is for issues that started showing up with a
  change in defconfig in this release to make cpuidle get turned on by
  default"

* tag 'spi-fix-v4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: omap2-mcspi: Add missing suspend and resume calls
  spi: mediatek: use correct mata->xfer_len when in fifo transfer
  spi: uniphier: fix incorrect property items
2018-11-28 08:33:55 -08:00
Lukas Wunner
3bd7f6589f
spi: bcm2835: Overcome sglist entry length limitation
When in DMA mode, the BCM2835 SPI controller requires that the FIFO is
accessed in 4 byte chunks.  This rule is not fulfilled if a transfer
consists of multiple sglist entries, one per page, and the first entry
starts in the middle of a page with an offset not a multiple of 4.

The driver currently falls back to programmed I/O for such transfers,
incurring a significant performance penalty.

Overcome this hardware limitation by transferring the first few bytes of
a transfer without DMA such that the remainder of the first sglist entry
becomes a multiple of 4.  Specifics are provided in kerneldoc comments.

An alternative approach would have been to split transfers in the
->prepare_message hook, but this may necessitate two transfers per page,
defeating the goal of clustering multiple pages together in a single
transfer for efficiency.  E.g. if the first TX sglist entry's length is
23 and the first RX's is 40, the first transfer would send and receive
23 bytes, the second 40 - 23 = 17 bytes, the third 4096 - 17 = 4079
bytes, the fourth 4096 - 4079 = 17 bytes and so on.  In other words,
O(n) transfers are necessary (n = number of sglist entries), whereas
the algorithm implemented herein only requires O(1) additional work.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-28 15:58:15 +00:00
Lukas Wunner
acf0f85695
spi: bcm2835: Document struct bcm2835_spi
Document the driver's data structure to lower the barrier to entry for
contributors.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-28 15:58:00 +00:00
Lukas Wunner
5c09e42f59
spi: bcm2835: Drop unused code for native Chip Select
Commit a30a555d74 ("spi: bcm2835: transform native-cs to gpio-cs on
first spi_setup") disabled the use of hardware-controlled native Chip
Select in favour of software-controlled GPIO Chip Select but left code
to support the former untouched.  Remove it to simplify the driver and
ease the addition of new features and further optimizations.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-28 15:55:43 +00:00
Mark Brown
c06eea7d2a
Merge branch 'spi-4.20' into spi-4.21 for bcm stuff. 2018-11-28 15:55:24 +00:00
Lukas Wunner
e82b0b3828
spi: bcm2835: Fix race on DMA termination
If a DMA transfer finishes orderly right when spi_transfer_one_message()
determines that it has timed out, the callbacks bcm2835_spi_dma_done()
and bcm2835_spi_handle_err() race to call dmaengine_terminate_all(),
potentially leading to double termination.

Prevent by atomically changing the dma_pending flag before calling
dmaengine_terminate_all().

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Fixes: 3ecd37edaa ("spi: bcm2835: enable dma modes for transfers meeting certain conditions")
Cc: stable@vger.kernel.org # v4.2+
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-28 15:42:50 +00:00
Lukas Wunner
dbc944115e
spi: bcm2835: Fix book-keeping of DMA termination
If submission of a DMA TX transfer succeeds but submission of the
corresponding RX transfer does not, the BCM2835 SPI driver terminates
the TX transfer but neglects to reset the dma_pending flag to false.

Thus, if the next transfer uses interrupt mode (because it is shorter
than BCM2835_SPI_DMA_MIN_LENGTH) and runs into a timeout,
dmaengine_terminate_all() will be called both for TX (once more) and
for RX (which was never started in the first place).  Fix it.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Fixes: 3ecd37edaa ("spi: bcm2835: enable dma modes for transfers meeting certain conditions")
Cc: stable@vger.kernel.org # v4.2+
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-28 15:42:47 +00:00
Lukas Wunner
56c1723426
spi: bcm2835: Avoid finishing transfer prematurely in IRQ mode
The IRQ handler bcm2835_spi_interrupt() first reads as much as possible
from the RX FIFO, then writes as much as possible to the TX FIFO.
Afterwards it decides whether the transfer is finished by checking if
the TX FIFO is empty.

If very few bytes were written to the TX FIFO, they may already have
been transmitted by the time the FIFO's emptiness is checked.  As a
result, the transfer will be declared finished and the chip will be
reset without reading the corresponding received bytes from the RX FIFO.

The odds of this happening increase with a high clock frequency (such
that the TX FIFO drains quickly) and either passing "threadirqs" on the
command line or enabling CONFIG_PREEMPT_RT_BASE (such that the IRQ
handler may be preempted between filling the TX FIFO and checking its
emptiness).

Fix by instead checking whether rx_len has reached zero, which means
that the transfer has been received in full.  This is also more
efficient as it avoids one bus read access per interrupt.  Note that
bcm2835_spi_transfer_one_poll() likewise uses rx_len to determine
whether the transfer has finished.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Fixes: e34ff011c7 ("spi: bcm2835: move to the transfer_one driver model")
Cc: stable@vger.kernel.org # v4.1+
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-28 15:42:41 +00:00
Leilk Liu
942779c6f1
spi: mediatek: add spi support for mt7629 IC
this patch add support for mt7629 IC.

Signed-off-by: Leilk Liu <leilk.liu@mediatek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-27 14:17:20 +00:00
Radu Pirea
96ed3ecde2
spi: at91-usart: add power management support
This patch implements power management callback function for USART as
SPI driver.

Signed-off-by: Radu Pirea <radu_nicolae.pirea@upb.ro>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-27 14:15:11 +00:00
Olof Johansson
1d2319efb6
spi: npcm: Fix uninitialized variable warning
The compiler has no way to know that rsize 1 or 2 are the only valid
values. Also simplify the code a bit with early return.

The warning was:

drivers/spi/spi-npcm-pspi.c:215:6: warning: 'val' may be used uninitialized in this function [-Wmaybe-uninitialized]

Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-27 14:07:08 +00:00
Dan Carpenter
428f977a6a
spi: npcm: Fix an error code in the probe function
There is an IS_ERR() vs PTR_ERR() typo here.  The current code returns 1
but we want to return the negative error code.

Fixes: 2a22f1b30c ("spi: npcm: add NPCM PSPI controller driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-23 13:25:59 +00:00
Ryan Case
478652f3d4
spi: spi-qcom-qspi: Fix remaining driver nits
Address remaining comments from original driver patch series

* Move RD_FIFO_CFG to be ordered corretly
* Expand spinlock comment

Signed-off-by: Ryan Case <ryandcase@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-22 14:38:13 +00:00
Boris Brezillon
aa167f3fed
spi: spi-mem: Add a new API to support direct mapping
Most modern SPI controllers can directly map a SPI memory (or a portion
of the SPI memory) in the CPU address space. Most of the time this
brings significant performance improvements as it automates the whole
process of sending SPI memory operations every time a new region is
accessed.

This new API allows SPI memory drivers to create direct mappings and
then use them to access the memory instead of using spi_mem_exec_op().

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-20 16:26:57 +00:00
Boris Brezillon
f86c24f479
spi: spi-mem: Split spi_mem_exec_op() code
The logic surrounding the ->exec_op() call applies to direct mapping
accessors. Move this code to separate functions to avoid duplicating
code.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-20 16:26:42 +00:00
Boris Brezillon
0ebb261a0b
spi: spi-mem: Add SPI_MEM_NO_DATA to the spi_mem_data_dir enum
When defining spi_mem_op templates we don't necessarily know the size
that will be passed when the template is actually used, and basing the
supports_op() check on op->data.nbytes to know whether there will be
data transferred for a specific operation is this not possible.

Add SPI_MEM_NO_DATA to the spi_mem_data_dir enum so that we can base
our checks on op->data.dir instead of op->data.nbytes.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-20 16:26:26 +00:00
Lubomir Rintel
f0915dfc44
spi: pxa2xx: Fix '"CONFIG_OF" is not defined' warning
A careless oversight. Sorry.

Fixes: 0a897143b7c9 ("spi: pxa2xx: Add slave mode support")
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-16 19:06:24 -08:00
Tony Lindgren
91b9deefed
spi: omap2-mcspi: Add missing suspend and resume calls
I've been wondering still about omap2-mcspi related suspend and resume
flakeyness and looks like we're missing calls to spi_master_suspend()
and spi_master_resume(). Adding those and using pm_runtime_force_suspend()
and pm_runtime_force_resume() makes things work for suspend and resume
and allows us to stop using noirq suspend and resume.

And while at it, let's use SET_SYSTEM_SLEEP_PM_OPS to simplify things
further.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-15 16:20:43 -08:00
Mark Brown
d57e79601b
spi: Fix core transfer waits after slave support
The refactoring done as part of adding the core support for handling
waiting for slave transfer dropped a conditional which meant that we
started waiting for completion of all transfers, not just those that the
controller asked for.  This caused hangs and massive delays on platforms
that don't need the core delay.  Re-add the delay to fix this.

Fixes: 810923f3bf (spi: Deal with slaves that return from transfer_one() unfinished)
Reported-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-15 16:08:32 -08:00
kbuild test robot
7986e2273c
spi: npcm: fix platform_no_drv_owner.cocci warnings
drivers/spi/spi-npcm-pspi.c:470:3-8: No need to set .owner here. The core will do it.

 Remove .owner field if calls are used which set it automatically

Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci

Fixes: 2a22f1b30c ("spi: npcm: add NPCM PSPI controller driver")
CC: Tomer Maimon <tmaimon77@gmail.com>
Signed-off-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-15 11:19:17 -08:00
Stefan Wahren
22bf6cd2ca
spi: bcm2835: make license text and module license match
The license text is specifying GPL v2 or later but the MODULE_LICENSE
is set to GPL v2 which means GNU Public License v2 only. So choose the
license text as the correct one.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Florian Kauer <florian.kauer@koalo.de>
Acked-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-14 14:18:18 -08:00
Colin Ian King
757ec116c9
spi: npcm: fix u32 csgpio being checked for less than zero
The u32 variable csgpio is being checked for an error return
from the call to of_get_named_gpio, however, since this is unsigned
this comparison will always be false. Fix this by making csgpio an
int and fix up the %u format specifiers to %d accordingly.

Detected by CoverityScan, CID#1475476 ("Unsigned compared against 0")

Fixes: 2a22f1b30c ("spi: npcm: add NPCM PSPI controller driver")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-14 14:02:33 -08:00
Tomer Maimon
2a22f1b30c
spi: npcm: add NPCM PSPI controller driver
Add Nuvoton NPCM BMC Peripheral SPI controller driver.

Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-13 12:01:22 -08:00
Fredrik Ternerot
c0b07605f1
spi: pl022: Handle cs_change for last transfer
Do not deselect cs when cs_change is set for the last transfer in the
message. In this case, cs_change indicates that cs should stay selected
until the next transfer.

Signed-off-by: Fredrik Ternerot <fredrikt@axis.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-13 10:05:49 -08:00