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2019-01-08cross-tree: phase out dma_zalloc_coherent()Luis Chamberlain1-3/+3
We already need to zero out memory for dma_alloc_coherent(), as such using dma_zalloc_coherent() is superflous. Phase it out. This change was generated with the following Coccinelle SmPL patch: @ replace_dma_zalloc_coherent @ expression dev, size, data, handle, flags; @@ -dma_zalloc_coherent(dev, size, handle, flags) +dma_alloc_coherent(dev, size, handle, flags) Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> [hch: re-ran the script on the latest tree] Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-12-25Merge tag 'spi-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spiLinus Torvalds25-711/+3105
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 ...
2018-12-20Merge remote-tracking branches 'spi/topic/mem' and 'spi/topic/mtd' into spi-nextMark Brown4-22/+806
2018-12-20spi: sh-msiof: Reduce the number of times write to and perform the transmission from FIFOHoan Nguyen An1-1/+9
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>
2018-12-13spi: lpspi: Let watermark change with send data lengthClark Wang1-2/+9
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>
2018-12-13spi: lpspi: Add slave mode supportClark Wang1-28/+79
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>
2018-12-13spi: lpspi: Replace all "master" with "controller"Clark Wang1-38/+46
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>
2018-12-11Merge branch 'for-linus' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator into regulator-4.21Mark Brown2-14/+27
2018-12-11spi: imx: drop useless member speed_hz from driver data structUwe Kleine-König1-7/+5
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>
2018-12-11spi: imx: rename config callback and add useful parametersUwe Kleine-König1-17/+22
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>
2018-12-11spi: imx: style fixesUwe Kleine-König1-7/+9
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>
2018-12-11spi: imx: mx51-ecspi: Move some initialisation to prepare_message hook.Uwe Kleine-König1-27/+40
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>
2018-12-11spi: imx: add a device specific prepare_message callbackUwe Kleine-König1-1/+39
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>
2018-12-11mtd: atmel-quadspi: disallow building on ebsa110Arnd Bergmann1-1/+1
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: 161aaab8a067 ("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
2018-12-06spi: npcm: Modify pspi send functionTomer Maimon1-6/+14
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>
2018-12-06spi: Use of_node_name_eq for node name comparisonsRob Herring1-1/+1
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>
2018-12-04Merge branch 'topic/3wire-gpio' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-4.21 mode conflictMark Brown1-3/+21
2018-12-04spi: dw-mmio: add ACPI supportJay Fang2-0/+9
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>
2018-12-04spi: bcm2835: Synchronize with callback on DMA terminationLukas Wunner1-6/+6
Commit b36f09c3c441 ("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 de92436ac40f ("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>
2018-12-04spi: bcm2835: Speed up FIFO access if fill level is knownLukas Wunner1-4/+60
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>
2018-12-04spi: bcm2835: Polish transfer of DMA prologueLukas Wunner1-25/+29
Commit 3bd7f6589f67 ("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>
2018-12-03spi: spi-mem: add support for octal mode I/O data transferYogesh Narayan Gaur1-1/+8
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>
2018-12-03spi: add support for octal mode I/O data transferYogesh Narayan Gaur1-2/+10
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>
2018-12-03spi: fix spi-at91-usart.c build errors when PINCTRL is not setRandy Dunlap1-0/+1
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>
2018-11-29spi: Fix formatting of header blockMark Brown1-6/+4
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>
2018-11-29Merge branch 'for-4.20' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-4.21Mark Brown1-1/+1
2018-11-29spi: bcm2835: Unbreak the build of esoteric configsLukas Wunner1-1/+1
Commit e82b0b382845 ("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: e82b0b382845 ("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>
2018-11-28Merge tag 'spi-fix-v4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spiLinus Torvalds2-14/+27
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
2018-11-28spi: bcm2835: Overcome sglist entry length limitationLukas Wunner1-49/+242
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>
2018-11-28spi: bcm2835: Document struct bcm2835_spiLukas Wunner1-0/+11
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>
2018-11-28spi: bcm2835: Drop unused code for native Chip SelectLukas Wunner1-83/+13
Commit a30a555d7435 ("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>
2018-11-28Merge branch 'spi-4.20' into spi-4.21 for bcm stuff.Mark Brown2-20/+31
2018-11-28spi: bcm2835: Fix race on DMA terminationLukas Wunner1-6/+4
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: 3ecd37edaa2a ("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>
2018-11-28spi: bcm2835: Fix book-keeping of DMA terminationLukas Wunner1-0/+1
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: 3ecd37edaa2a ("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>
2018-11-28spi: bcm2835: Avoid finishing transfer prematurely in IRQ modeLukas Wunner1-2/+1
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: e34ff011c70e ("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>
2018-11-27spi: mediatek: add spi support for mt7629 ICLeilk Liu1-0/+3
this patch add support for mt7629 IC. Signed-off-by: Leilk Liu <leilk.liu@mediatek.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-27spi: at91-usart: add power management supportRadu Pirea1-0/+61
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>
2018-11-27spi: npcm: Fix uninitialized variable warningOlof Johansson1-7/+15
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>
2018-11-23spi: npcm: Fix an error code in the probe functionDan Carpenter1-1/+1
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: 2a22f1b30cee ("spi: npcm: add NPCM PSPI controller driver") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-22spi: spi-qcom-qspi: Fix remaining driver nitsRyan Case1-4/+4
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>
2018-11-20spi: spi-mem: Add a new API to support direct mappingBoris Brezillon1-0/+204
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>
2018-11-20spi: spi-mem: Split spi_mem_exec_op() codeBoris Brezillon1-21/+42
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>
2018-11-20spi: spi-mem: Add SPI_MEM_NO_DATA to the spi_mem_data_dir enumBoris Brezillon1-1/+1
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>
2018-11-16spi: pxa2xx: Fix '"CONFIG_OF" is not defined' warningLubomir Rintel1-7/+1
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>
2018-11-15spi: omap2-mcspi: Add missing suspend and resume callsTony Lindgren1-12/+25
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>
2018-11-15spi: Fix core transfer waits after slave supportMark Brown1-3/+5
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: 810923f3bf06c11 (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>
2018-11-15spi: npcm: fix platform_no_drv_owner.cocci warningskbuild test robot1-1/+0
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: 2a22f1b30cee ("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>
2018-11-14spi: bcm2835: make license text and module license matchStefan Wahren2-2/+2
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>
2018-11-14spi: npcm: fix u32 csgpio being checked for less than zeroColin Ian King1-3/+3
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: 2a22f1b30cee ("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>
2018-11-13spi: npcm: add NPCM PSPI controller driverTomer Maimon3-0/+488
Add Nuvoton NPCM BMC Peripheral SPI controller driver. Signed-off-by: Tomer Maimon <tmaimon77@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>