linux/drivers/spi
Thommy Jakobsson 5dd8304981
spi/zynqmp: remove entry that causes a cs glitch
In the public interface for chipselect, there is always an entry
commented as "Dummy generic FIFO entry" pushed down to the fifo right
after the activate/deactivate command. The dummy entry is 0x0,
irregardless if the intention was to activate or deactive the cs. This
causes the cs line to glitch rather than beeing activated in the case
when there was an activate command.

This has been observed on oscilloscope, and have caused problems for at
least one specific flash device type connected to the qspi port. After
the change the glitch is gone and cs goes active when intended.

The reason why this worked before (except for the glitch) was because
when sending the actual data, the CS bits are once again set. Since
most flashes uses mode 0, there is always a half clk period anyway for
cs to clk active setup time. If someone would rely on timing from a
chip_select call to a transfer_one, it would fail though.

It is unknown why the dummy entry was there in the first place, git log
seems to be of no help in this case. The reference manual gives no
indication of the necessity of this. In fact the lower 8 bits are a
setup (or hold in case of deactivate) time expressed in cycles. So this
should not be needed to fulfill any setup/hold timings.

Signed-off-by: Thommy Jakobsson <thommyj@gmail.com>
Reviewed-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
Link: https://lore.kernel.org/r/20200224162643.29102-1-thommyj@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-02-27 12:48:56 +00:00
..
atmel-quadspi.c spi: Remove dev_err() usage after platform_get_irq() 2019-08-02 12:15:43 +01:00
internals.h spi: Add an helper to flush the message queue 2018-04-23 15:48:18 +01:00
Kconfig spi: Add HiSilicon v3xx SPI NOR flash controller driver 2020-01-10 14:14:34 +00:00
Makefile spi: Add HiSilicon v3xx SPI NOR flash controller driver 2020-01-10 14:14:34 +00:00
spi-altera.c spi: altera: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:14:50 +01:00
spi-armada-3700.c spi: a3700: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:15:09 +01:00
spi-at91-usart.c spi: at91-usart: Use dma_request_chan() directly for channel request 2019-11-15 12:13:02 +00:00
spi-ath79.c spi: ath79: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:15:29 +01:00
spi-atmel.c spi: atmel: Use dma_request_chan() instead dma_request_slave_channel() 2019-12-16 11:56:07 +00:00
spi-au1550.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 2019-05-30 11:26:37 -07:00
spi-axi-spi-engine.c spi: spi-axi: extend support for the delay field 2019-10-15 11:47:26 +01:00
spi-bcm63xx-hsspi.c spi: use new spi_transfer_delay_exec helper where straightforward 2019-10-15 11:51:57 +01:00
spi-bcm63xx.c spi: bcm63xx: extend error condition to delay as well 2019-10-15 11:47:06 +01:00
spi-bcm2835.c spi: bcm2835: Raise maximum number of slaves to 4 2020-01-09 21:25:44 +00:00
spi-bcm2835aux.c spi: bcm2835aux: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:16:08 +01:00
spi-bcm-qspi.c spi: bcm-qspi: Use platform_get_irq_byname_optional() to avoid error message 2020-01-07 22:32:04 +00:00
spi-bcm-qspi.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 459 2019-06-19 17:09:09 +02:00
spi-bitbang-txrx.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
spi-bitbang.c spi: bitbang: Make chipselect callback optional 2019-12-09 18:46:34 +00:00
spi-brcmstb-qspi.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 459 2019-06-19 17:09:09 +02:00
spi-butterfly.c spi: docs: convert to ReST and add it to the kABI bookset 2019-07-31 14:13:13 -06:00
spi-cadence.c spi: cadence: Correct handling of native chipselect 2019-11-27 12:54:45 +00:00
spi-cavium-octeon.c spi: octeon: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:17:27 +01:00
spi-cavium-thunderx.c spi: spi-cavium-thunderx: Add missing pci_release_regions() 2019-12-09 18:44:19 +00:00
spi-cavium.c spi: use new spi_transfer_delay_exec helper where straightforward 2019-10-15 11:51:57 +01:00
spi-cavium.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
spi-clps711x.c spi: clps711x: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:17:36 +01:00
spi-coldfire-qspi.c spi: coldfire-qspi: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:17:56 +01:00
spi-davinci.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 2019-05-30 11:26:37 -07:00
spi-dln2.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 372 2019-06-05 17:37:10 +02:00
spi-dw-mid.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288 2019-06-05 17:36:37 +02:00
spi-dw-mmio.c Merge branch 'spi-5.5' into spi-next 2019-11-22 19:56:35 +00:00
spi-dw-pci.c spi: dw-pci: Fix Chip Select amount on Intel Elkhart Lake PSE SPI 2019-10-22 17:57:43 +01:00
spi-dw.c Merge branch 'for-5.5' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-5.6 2019-12-25 18:18:54 +00:00
spi-dw.h spi: dw: Drop GPIO header 2019-10-30 14:14:50 +00:00
spi-efm32.c spi: Remove dev_err() usage after platform_get_irq() 2019-08-02 12:15:43 +01:00
spi-ep93xx.c spi: Remove dev_err() usage after platform_get_irq() 2019-08-02 12:15:43 +01:00
spi-falcon.c spi: spi-falcon: extend warning to delay as well 2019-10-15 11:46:57 +01:00
spi-fsl-cpm.c spi: fsl-cpm: Correct the free:ing 2019-11-15 12:12:15 +00:00
spi-fsl-cpm.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
spi-fsl-dspi.c spi: spi-fsl-dspi: Use dma_request_chan() instead dma_request_slave_channel() 2019-12-16 11:57:46 +00:00
spi-fsl-espi.c spi: use new spi_transfer_delay_exec helper where straightforward 2019-10-15 11:51:57 +01:00
spi-fsl-lib.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
spi-fsl-lib.h spi: fsl: Convert to use CS GPIO descriptors 2019-08-28 14:10:41 +01:00
spi-fsl-lpspi.c spi: fsl-lpspi: fix only one cs-gpio working 2020-01-14 16:03:29 +00:00
spi-fsl-qspi.c Merge branch 'for-5.4' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-5.5 2019-10-08 19:12:28 +01:00
spi-fsl-spi.c spi: fsl: simplify error path in of_fsl_spi_probe() 2020-01-14 16:08:29 +00:00
spi-fsl-spi.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
spi-geni-qcom.c spi: spi-geni-qcom: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:18:25 +01:00
spi-gpio.c Merge branch 'for-5.4' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-5.5 2019-10-08 19:12:28 +01:00
spi-hisi-sfc-v3xx.c spi: Add HiSilicon v3xx SPI NOR flash controller driver 2020-01-10 14:14:34 +00:00
spi-img-spfi.c spi: img-spfi: Use dma_request_chan() instead dma_request_slave_channel() 2019-12-16 11:57:06 +00:00
spi-imx.c spi: imx: use true,false for bool variable 2019-12-25 18:17:25 +00:00
spi-iproc-qspi.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
spi-jcore.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
spi-lantiq-ssc.c spi: lantiq-ssc: Use devm_platform_ioremap_resource() in lantiq_ssc_probe() 2019-10-01 12:34:18 +01:00
spi-lm70llp.c spi: docs: convert to ReST and add it to the kABI bookset 2019-07-31 14:13:13 -06:00
spi-loopback-test.c spi: spi-loopback-test: use new delay field 2019-10-15 11:45:19 +01:00
spi-lp8841-rtc.c spi: lp-8841: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:18:35 +01:00
spi-mem.c spi: spi-mem: fallback to using transfers when CS gpios are used 2019-11-07 13:11:18 +00:00
spi-meson-spicc.c spi: meson-spicc: Use GPIO descriptors 2019-12-16 11:58:48 +00:00
spi-meson-spifc.c spi: spi-meson-spifc: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:19:14 +01:00
spi-mpc52xx-psc.c spi: use new spi_transfer_delay_exec helper where straightforward 2019-10-15 11:51:57 +01:00
spi-mpc52xx.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428 2019-06-05 17:37:16 +02:00
spi-mpc512x-psc.c spi: use new spi_transfer_delay_exec helper where straightforward 2019-10-15 11:51:57 +01:00
spi-mt65xx.c spi: mediatek: add SPI_CS_HIGH support 2019-11-18 17:47:00 +00:00
spi-mt7621.c spi: mt7621: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:19:34 +01:00
spi-mxic.c Merge branch 'for-5.4' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-5.5 2019-10-08 19:12:28 +01:00
spi-mxs.c spi: mxs: Use dma_request_chan() instead dma_request_slave_channel() 2019-12-16 11:57:26 +00:00
spi-npcm-fiu.c spi: npcm-fiu: remove set but not used variable 'retlen' 2019-09-05 18:19:45 +01:00
spi-npcm-pspi.c spi: npcm-pspi: modify reset support 2020-01-17 15:38:21 +00:00
spi-nxp-fspi.c spi: nxp-fspi: Ensure width is respected in spi-mem operations 2019-12-16 11:54:34 +00:00
spi-oc-tiny.c spi: oc-tiny: Use GPIO descriptors 2019-12-27 01:08:11 +00:00
spi-omap2-mcspi.c spi: spi-omap2-mcspi: Support probe deferral for DMA channels 2020-02-06 15:53:57 +00:00
spi-omap-100k.c spi: use new spi_transfer_delay_exec helper where straightforward 2019-10-15 11:51:57 +01:00
spi-omap-uwire.c
spi-orion.c spi: orion: use new word_delay field for SPI transfers 2019-10-15 11:43:31 +01:00
spi-pic32-sqi.c spi: pic32-sqi: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:20:52 +01:00
spi-pic32.c spi: pic32: Retire dma_request_slave_channel_compat() 2019-11-22 19:53:41 +00:00
spi-pl022.c spi: pl022: Use dma_request_chan() directly for channel request 2019-11-15 12:14:19 +00:00
spi-ppc4xx.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
spi-pxa2xx-dma.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
spi-pxa2xx-pci.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
spi-pxa2xx.c spi: pxa2xx: Add CS control clock quirk 2020-02-26 18:45:06 +00:00
spi-pxa2xx.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
spi-qcom-qspi.c spi: spi-qcom-qspi: Use device managed memory for clk_bulk_data 2020-01-13 15:04:40 +00:00
spi-qup.c spi: qup: call spi_qup_pm_resume_runtime before suspending 2020-02-21 13:48:08 +00:00
spi-rb4xx.c spi: rb4xx: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:21:21 +01:00
spi-rockchip.c Linux 5.2-rc4 2019-06-10 18:52:53 +01:00
spi-rspi.c spi: rspi: Add support for GPIO chip selects 2020-01-07 22:34:07 +00:00
spi-s3c24xx-fiq.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
spi-s3c24xx-fiq.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
spi-s3c24xx.c spi: s3c24xx: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:21:31 +01:00
spi-s3c64xx.c spi: s3c64xx: Use dma_request_chan() directly for channel request 2019-11-15 12:14:39 +00:00
spi-sc18is602.c spi: use new spi_transfer_delay_exec helper where straightforward 2019-10-15 11:51:57 +01:00
spi-sh-hspi.c spi: use new spi_transfer_delay_exec helper where straightforward 2019-10-15 11:51:57 +01:00
spi-sh-msiof.c spi: sh-msiof: Do not redefine STR while compile testing 2020-01-09 13:27:05 +00:00
spi-sh-sci.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
spi-sh.c spi: Remove dev_err() usage after platform_get_irq() 2019-08-02 12:15:43 +01:00
spi-sifive.c spi: sifive: disable clk when probe fails and remove 2019-11-04 13:26:11 +00:00
spi-sirf.c spi: sirf: Use dma_request_chan() instead dma_request_slave_channel() 2019-12-16 11:57:36 +00:00
spi-slave-mt27xx.c spi: mediatek: Use devm_platform_ioremap_resource() in mtk_spi_slave_probe() 2019-10-01 12:34:58 +01:00
spi-slave-system-control.c spi: slave: Fix missing break in switch 2018-10-03 16:23:10 +01:00
spi-slave-time.c
spi-sprd-adi.c spi: sprd: adi: Set BIT_WDG_NEW bit when rebooting 2019-10-28 13:17:10 +00:00
spi-sprd.c spi: sprd: Fix the incorrect SPI register 2019-12-04 12:14:13 +00:00
spi-st-ssc4.c spi: st-ssc4: add missed pm_runtime_disable 2019-11-18 12:59:11 +00:00
spi-stm32-qspi.c spi: stm32-qspi: Use dma_request_chan() instead dma_request_slave_channel() 2019-12-16 11:58:08 +00:00
spi-stm32.c spi: stm32: Use dma_request_chan() instead dma_request_slave_channel() 2019-12-16 11:58:28 +00:00
spi-sun4i.c spi: sun4i: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:22:29 +01:00
spi-sun6i.c spi: sun6i: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:22:49 +01:00
spi-synquacer.c spi: Remove dev_err() usage after platform_get_irq() 2019-08-02 12:15:43 +01:00
spi-tegra20-sflash.c spi: tegra20-sflash: use to new spi_transfer_delay_exec 2019-10-15 11:45:07 +01:00
spi-tegra20-slink.c spi: tegra20-slink: add missed clk_unprepare 2019-11-15 12:15:22 +00:00
spi-tegra114.c spi: tegra114: use true,false for bool variable 2019-12-25 18:17:42 +00:00
spi-test.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 2019-05-30 11:26:37 -07:00
spi-ti-qspi.c spi: spi-ti-qspi: fix warning 2020-01-17 15:37:44 +00:00
spi-tle62x0.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
spi-topcliff-pch.c spi/topcliff-pch: Remove unneeded semicolon 2019-12-09 18:45:53 +00:00
spi-txx9.c spi: txx9: Convert to use GPIO descriptors 2019-10-30 14:14:32 +00:00
spi-uniphier.c spi: uniphier: Add DMA transfer mode support 2019-12-25 18:21:05 +00:00
spi-xcomm.c spi: use new spi_transfer_delay_exec helper where straightforward 2019-10-15 11:51:57 +01:00
spi-xilinx.c spi: xilinx: Add DT support for selecting transfer word width 2019-10-24 12:45:21 +01:00
spi-xlp.c spi: xlp: use devm_platform_ioremap_resource() to simplify code 2019-09-04 17:23:28 +01:00
spi-xtensa-xtfpga.c spi: xtensa-xtfpga: Use devm_platform_ioremap_resource() in xtfpga_spi_probe() 2019-10-01 12:35:18 +01:00
spi-zynq-qspi.c spi: zynq-qspi: Support two chip selects 2019-11-08 17:45:09 +00:00
spi-zynqmp-gqspi.c spi/zynqmp: remove entry that causes a cs glitch 2020-02-27 12:48:56 +00:00
spi.c spi: Add generic support for unused native cs with cs-gpios 2020-01-07 22:32:25 +00:00
spidev.c spi: spidev: Fix CS polarity if GPIO descriptors are used 2020-02-21 13:50:36 +00:00