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| * spi: dw: Remove runtime PM enable/disable from common part of the driverJarkko Nikula2019-10-301-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Committed version of the commit b9fc2d207e54 ("spi: dw: Move runtime PM enable/disable from common to platform driver part") does not include by some reason changes to drivers/spi/spi-dw.c that were part of the original patch sent to the mailing list. Complete the code move by doing those changes now. Fixes: b9fc2d207e54 ("spi: dw: Move runtime PM enable/disable from common to platform driver part") Cc: Phil Edworthy <phil.edworthy@renesas.com> Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Link: https://lore.kernel.org/r/20191030113137.15459-1-jarkko.nikula@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: sprd: adi: Set BIT_WDG_NEW bit when rebootingLingling Xu2019-10-281-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When rebooting system, the PMIC watchdog time loading may not be loaded correctly when another system is feeding the PMIC watchdog, since we did not check the watchdog busy status before loading time values. Thus we should set the BIT_WDG_NEW bit before loading time values, that can support multiple loads without checking busy status to make sure the time values can be loaded successfully to avoid this potential issue. Signed-off-by: Lingling Xu <ling_ling.xu@unisoc.com> Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Link: https://lore.kernel.org/r/5655318a7252c9ea518c2f7950a61228ab8f42bf.1572257085.git.baolin.wang@linaro.org Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: sprd: adi: Add missing lock protection when rebootingLingling Xu2019-10-281-0/+3
| | | | | | | | | | | | | | | | | | | | | | When rebooting the system, we should lock the watchdog after configuration to make sure the watchdog can reboot the system successfully. Signed-off-by: Lingling Xu <ling_ling.xu@unisoc.com> Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Link: https://lore.kernel.org/r/7b04711127434555e3a1a86bc6be99860cd86668.1572257085.git.baolin.wang@linaro.org Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: pxa2xx: Introduce temporary variables to increase readabilityAndy Shevchenko2019-10-251-5/+6
| | | | | | | | | | | | | | | | | | | | The current conditional for PCI ID matching is hard to read. Introduce couple of temporary variables to increase readability of the code. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20191021103625.4250-1-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: xilinx: Add DT support for selecting transfer word widthAlvaro Gamez Machado2019-10-241-1/+6
| | | | | | | | | | | | | | | | | | | | This core supports either 8, 16 or 32 bits as word width. This value is only settable on instantiation, and thus we need to support any of them by means of the device tree. Signed-off-by: Alvaro Gamez Machado <alvaro.gamez@hazent.com> Link: https://lore.kernel.org/r/20191024110757.25820-3-alvaro.gamez@hazent.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: Fix spelling in the commentsAndy Shevchenko2019-10-231-2/+2
| | | | | | | | | | | | | | | | Two spelling mistakes are being fixed. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20191023121643.25237-1-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: dw-pci: Fix Chip Select amount on Intel Elkhart Lake PSE SPIJarkko Nikula2019-10-221-1/+1
| | | | | | | | | | | | | | | | | | | | Intel(R) Programmable Services Engine (Intel(R) PSE) SPI controllers in Intel Elkhart Lake have two Chip Select signals instead of one. Reported-by: Raymond Tan <raymond.tan@intel.com> Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Link: https://lore.kernel.org/r/20191018132131.31608-3-jarkko.nikula@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: dw-pci: Add runtime power management supportRaymond Tan2019-10-221-0/+9
| | | | | | | | | | | | | | | | | | | | | | Implement pm_runtime hooks at pci driver. Signed-off-by: Raymond Tan <raymond.tan@intel.com> [jarkko.nikula@linux.intel.com: Forward ported on top of commit 1e6959832510 ("spi: dw: Add basic runtime PM support")] Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Link: https://lore.kernel.org/r/20191018132131.31608-2-jarkko.nikula@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: atmel: Improve CS0 case support on AT91RM9200Gregory CLEMENT2019-10-181-3/+12
| | | | | | | | | | | | | | | | | | | | | | Thanks to the recent change in this driver, it is now possible to prevent using the CS0 with GPIO during setup. It then allows to remove the special handling of this case in the cs_activate() and cs_deactivate() functions. Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Link: https://lore.kernel.org/r/20191017141846.7523-8-gregory.clement@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: atmel: Improve and fix GPIO CS usageGregory CLEMENT2019-10-181-8/+66
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the previous implementation of this driver, the index of the GPIO used as CS was linked to the offset of the CS register used to configure the transfer. With this new implementation the first CS register not used by internal CS is associated to all the GPIO CS. It allows to not be anymore limited to have only 4 CS managed, now it is possible to have in the same time until 3 internal CS and no more limit for the CS GPIO. Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Link: https://lore.kernel.org/r/20191017141846.7523-7-gregory.clement@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: atmel: Remove platform data supportGregory CLEMENT2019-10-182-14/+3
| | | | | | | | | | | | | | | | | | This driver is now only used through the device tree. Simplify code by explicitly depend on device tree. Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Link: https://lore.kernel.org/r/20191017141846.7523-6-gregory.clement@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: atmel: Remove useless private fieldGregory CLEMENT2019-10-181-11/+6
| | | | | | | | | | | | | | | | | | | | Since the conversion to GPIO descriptor, the GPIO used as chip select, can be directly access from the spi_device struct. So there is no need to keep the field npcs_pin. Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Link: https://lore.kernel.org/r/20191017141846.7523-5-gregory.clement@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: atmel: Configure GPIO per CS instead of by controllerGregory CLEMENT2019-10-181-24/+8
| | | | | | | | | | | | | | | | | | | | Instead of setting up the GPIO configuration for the whole controller, do it at CS level. It will allow to mix internal CS and GPIO CS, which is not possible with the current implementation. Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Link: https://lore.kernel.org/r/20191017141846.7523-4-gregory.clement@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: atmel: Fix CS high supportGregory CLEMENT2019-10-181-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Until a few years ago, this driver was only used with CS GPIO. The only exception is CS0 on AT91RM9200 which has to use internal CS. A limitation of the internal CS is that they don't support CS High. So by using the CS GPIO the CS high configuration was available except for the particular case CS0 on RM9200. When the support for the internal chip-select was added, the check of the CS high support was not updated. Due to this the driver accepts this configuration for all the SPI controller v2 (used by all SoCs excepting the AT91RM9200) whereas the hardware doesn't support it for infernal CS. This patch fixes the test to match the hardware capabilities. Fixes: 4820303480a1 ("spi: atmel: add support for the internal chip-select of the spi controller") Cc: <stable@vger.kernel.org> Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Link: https://lore.kernel.org/r/20191017141846.7523-3-gregory.clement@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: atmel: Remove and fix erroneous commentsGregory CLEMENT2019-10-181-7/+3
| | | | | | | | | | | | | | | | | | Since CSAAT functionality support has been added. Some comments become wrong. Fix them to match the current driver behavior. Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Link: https://lore.kernel.org/r/20191017141846.7523-2-gregory.clement@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: pxa2xx: Replace of_device.h with mod_devicetable.h and of.hAndy Shevchenko2019-10-181-1/+2
| | | | | | | | | | | | | | | | | | There is nothing in use from of_device.h. The definitions and macros are available thru mod_devicetable.h and of.h. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20191018105429.82782-5-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: pxa2xx: Convert to use device_get_match_data()Andy Shevchenko2019-10-181-19/+7
| | | | | | | | | | | | | | | | | | | | Convert to use device_get_match_data() instead of open coded variant. While here, switch of_property_read_bool() to device_property_read_bool(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20191018105429.82782-4-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: pxa2xx: Convert pxa2xx_spi_get_port_id() to take struct deviceAndy Shevchenko2019-10-181-3/+5
| | | | | | | | | | | | | | | | This is preparatory patch before converting to use device_get_match_data() API. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20191018105429.82782-3-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: pxa2xx: Sort headersAndy Shevchenko2019-10-181-12/+12
| | | | | | | | | | | | | | | | | | Sort the headers in alphabetic order in order to ease the maintenance for this part. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20191018105429.82782-2-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: pxa2xx: No need to keep pointer to platform deviceAndy Shevchenko2019-10-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is no need to keep a pointer to the platform device. Currently there are no users of it directly, and if there will be in the future we may restore it from pointer to the struct device. Convert all users at the same time. Cc: Russell King <linux@armlinux.org.uk> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Takashi Iwai <tiwai@suse.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20191018105429.82782-1-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: use new `spi_transfer_delay_exec` helper where straightforwardAlexandru Ardelean2019-10-1515-46/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For many places in the spi drivers, using the new `spi_transfer_delay` helper is straightforward. It's just replacing: ``` if (t->delay_usecs) udelay(t->delay_usecs); ``` with `spi_transfer_delay(t)` which handles both `delay_usecs` and the new `delay` field. This change replaces in all places (in the spi drivers) where this change is simple. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-10-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: spi-axi: extend support for the `delay` fieldAlexandru Ardelean2019-10-151-3/+13
| | | | | | | | | | | | | | | | | | | | | | The AXI SPI engine driver uses the `delay_usecs` field from `spi_transfer` to configure delays, which the controller will execute. This change extends the logic to also include the `delay` value, in case it is used (instead if `delay_usecs`). Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-20-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: bcm63xx: extend error condition to `delay` as wellAlexandru Ardelean2019-10-151-1/+1
| | | | | | | | | | | | | | | | | | | | The driver errors out if `delay_usecs` is non-zero. This error condition should be extended to the new `delay` field, to account for when it will be used. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-19-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: spi-falcon: extend warning to `delay` as wellAlexandru Ardelean2019-10-151-1/+1
| | | | | | | | | | | | | | | | | | | | The WARN_ON macro prints a warning in syslog if `delay_usecs` is non-zero. However, with the new intermediate `delay`, the warning should also be printed. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-18-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: spi-fsl-espi: convert transfer delay to `spi_delay` formatAlexandru Ardelean2019-10-152-7/+18
| | | | | | | | | | | | | | | | | | | | | | | | The way the max delay is computed for this controller, it looks like it is searching for the max delay from an SPI message a using that. No idea if this is valid. But this change should support both `delay_usecs` and the new `delay` data which is of `spi_delay` type. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-17-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: implement SW control for CS timesAlexandru Ardelean2019-10-151-1/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change implements CS control for setup, hold & inactive delays. The `cs_setup` delay is completely new, and can help with cases where asserting the CS, also brings the device out of power-sleep, where there needs to be a longer (than usual), before transferring data. The `cs_hold` time can overlap with the `delay` (or `delay_usecs`) from an SPI transfer. The main difference is that `cs_hold` implies that CS will be de-asserted. The `cs_inactive` delay does not have a clear use-case yet. It has been implemented mostly because the `spi_set_cs_timing()` function implements it. To some degree, this could overlap or replace `cs_change_delay`, but this will require more consideration/investigation in the future. All these delays have been added to the `spi_controller` struct, as they would typically be configured by calling `spi_set_cs_timing()` after an `spi_setup()` call. Software-mode for CS control, implies that the `set_cs_timing()` hook has not been provided for the `spi_controller` object. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-16-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: tegra114: change format for `spi_set_cs_timing()` functionAlexandru Ardelean2019-10-152-8/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The initial version of `spi_set_cs_timing()` was implemented with consideration only for clock-cycles as delay. For cases like `CS setup` time, it's sometimes needed that micro-seconds (or nano-seconds) are required, or sometimes even longer delays, for cases where the device needs a little longer to start transferring that after CS is asserted. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-15-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: spidev: use new `delay` field for spi transfersAlexandru Ardelean2019-10-151-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The `delay` field has type `struct spi_delay`. This allows users to specify nano-second or clock-cycle delays (if needed). Converting to use `delay` is straightforward: it's just assigning the value to `delay.value` and hard-coding the `delay.unit` to `SPI_DELAY_UNIT_USECS`. This keeps the uapi for spidev un-changed. Changing it can be part of another changeset and discussion. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-14-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: spi-loopback-test: use new `delay` fieldAlexandru Ardelean2019-10-151-3/+9
| | | | | | | | | | | | | | | | | | | | This change replaces the use of the `delay_usecs` field with the new `delay` field. The code/test still uses micro-seconds, but they are now configured and used via the `struct spi_delay` format of the `delay` field. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-13-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: tegra20-sflash: use to new `spi_transfer_delay_exec`Alexandru Ardelean2019-10-151-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This conversion to the spi_transfer_delay_exec() helper is not straightforward, as it seems that when a delay is present, the controller issues a command, and then a delay is followed. This change adds support for the new `delay` field which is of type `spi_delay` and keeps backwards compatibility with the old `delay_usecs` field. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-12-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: tegra114: use `spi_transfer_delay_exec` helperAlexandru Ardelean2019-10-151-14/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The tegra114 driver has a weird/separate `tegra_spi_transfer_delay()` function that does 2 delays: one mdelay() and one udelay(). This was introduced via commit f4fade12d506e14867a2b0a5e2f7aaf227297d8b ("spi/tegra114: Correct support for cs_change"). There doesn't seem to be a mention in that commit message to suggest a specific need/use-case for having the 2 delay calls. For the most part, udelay() should be sufficient. This change replaces it with the new `spi_transfer_delay_exec()`, which should do the same thing. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-11-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: introduce `delay` field for `spi_transfer` + spi_transfer_delay_exec()Alexandru Ardelean2019-10-151-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The change introduces the `delay` field to the `spi_transfer` struct as an `struct spi_delay` type. This intends to eventually replace `delay_usecs`. But, since there are many users of `delay_usecs`, this needs some intermediate work. A helper called `spi_transfer_delay_exec()` is also added, which maintains backwards compatibility with `delay_usecs`, by assigning the value to `delay` if non-zero. This should maintain backwards compatibility with current users of `udelay_usecs`. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-9-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: core,atmel: convert `word_delay_usecs` -> `word_delay` for spi_deviceAlexandru Ardelean2019-10-152-4/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change does a conversion from the `word_delay_usecs` -> `word_delay` for the `spi_device` struct. This allows users to specify inter-word delays in other unit types (nano-seconds or clock cycles), depending on how users want. The Atmel SPI driver is the only current user of the `word_delay_usecs` field (from the `spi_device` struct). So, it needed a slight conversion to use the `word_delay` as an `spi_delay` struct. In SPI core, the only required mechanism is to update the `word_delay` information per `spi_transfer`. This requires a bit more logic than before, because it needs that both delays be converted to a common unit (nano-seconds) for comparison. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-8-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: spidev: use new `word_delay` field for spi transfersAlexandru Ardelean2019-10-151-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The `word_delay` field had it's type changed to `struct spi_delay`. This allows users to specify nano-second or clock-cycle delays (if needed). Converting to use `word_delay` is straightforward: it's just assigning the value to `word_delay.value` and hard-coding the `word_delay.unit` to `SPI_DELAY_UNIT_USECS` This keeps the uapi for spidev un-changed. Changing it can be part of another changeset and discussion. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-7-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: orion: use new `word_delay` field for SPI transfersAlexandru Ardelean2019-10-151-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | The `word_delay` field had it's type changed to `struct spi_delay`. This allows users to specify nano-second or clock-cycle delays (if needed). Converting to use `word_delay` is straightforward: it just uses the new `spi_delay_exec()` routine, that handles the `unit` part. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-6-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: sprd: convert transfer word delay to spi_delay structAlexandru Ardelean2019-10-151-3/+12
| | | | | | | | | | | | | | | | | | | | | | | | The Spreadtrum SPI driver is the only user of the `word_delay` field in the `spi_transfer` struct. This change converts the field to use the `spi_delay` struct. This also enforces the users to specify the delay unit to be `SPI_DELAY_UNIT_SCK`. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-5-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: make `cs_change_delay` the first user of the `spi_delay` logicAlexandru Ardelean2019-10-151-21/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since the logic for `spi_delay` struct + `spi_delay_exec()` has been copied from the `cs_change_delay` logic, it's natural to make this delay, the first user. The `cs_change_delay` logic requires that the default remain 10 uS, in case it is unspecified/unconfigured. So, there is some special handling needed to do that. The ADIS library is one of the few users of the new `cs_change_delay` parameter for an spi_transfer. The introduction of the `spi_delay` struct, requires that the users of of `cs_change_delay` get an update. This change also updates the ADIS library. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-4-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: introduce spi_delay struct as "value + unit" & spi_delay_exec()Alexandru Ardelean2019-10-151-0/+51
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are plenty of delays that have been introduced in SPI core. Most of them are in micro-seconds, some need to be in nano-seconds, and some in clock-cycles. For some of these delays (related to transfers & CS timing) it may make sense to have a `spi_delay` struct that abstracts these a bit. The important element of these delays [for unification] seems to be the `unit` of the delay. It looks like micro-seconds is good enough for most people, but every-once in a while, some delays seem to require other units of measurement. This change adds the `spi_delay` struct & a `spi_delay_exec()` function that processes a `spi_delay` object/struct to execute the delay. It's a copy of the `cs_change_delay` mechanism, but without the default for 10 uS. The clock-cycle delay unit is a bit special, as it needs to be bound to an `spi_transfer` object to execute. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-3-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: move `cs_change_delay` backwards compat logic outside switchAlexandru Ardelean2019-10-151-6/+5
| | | | | | | | | | | | | | | | | | | | The `cs_change_delay` backwards compatibility value could be moved outside of the switch statement. The only reason to do it, is to make the next patches easier to diff. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-2-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: npcm: Remove set but not used variable 'val'zhengbin2019-10-091-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fixes gcc '-Wunused-but-set-variable' warning: drivers/spi/spi-npcm-pspi.c: In function npcm_pspi_handler: drivers/spi/spi-npcm-pspi.c:296:6: warning: variable val set but not used [-Wunused-but-set-variable] It is not used since commit 2a22f1b30cee ("spi: npcm: add NPCM PSPI controller driver") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: zhengbin <zhengbin13@huawei.com> Link: https://lore.kernel.org/r/1570581437-104549-3-git-send-email-zhengbin13@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: omap-100k: Remove set but not used variable 'dataH'zhengbin2019-10-091-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Fixes gcc '-Wunused-but-set-variable' warning: drivers/spi/spi-omap-100k.c: In function spi100k_read_data: drivers/spi/spi-omap-100k.c:140:6: warning: variable dataH set but not used [-Wunused-but-set-variable] It is not used since commit 35c9049b2704 ("Add OMAP spi100k driver") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: zhengbin <zhengbin13@huawei.com> Link: https://lore.kernel.org/r/1570581437-104549-2-git-send-email-zhengbin13@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * Merge branch 'for-5.4' of ↵Mark Brown2019-10-087-14/+45
| |\ | | | | | | | | | https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-5.5
| * | spi: spi-fsl-dspi: Implement the PTP system timestamping for TCFQ modeVladimir Oltean2019-10-071-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In this mode, the DSPI controller uses PIO to transfer word by word. In comparison, in EOQ mode the 4-word deep FIFO is being used, hence the current logic will need some adaptation for which I do not have the hardware (Coldfire) to test. It is not clear what is the timing of DMA transfers and whether timestamping in the driver brings any overall performance increase compared to regular timestamping done in the core. Short phc2sys summary after 58 minutes of running on LS1021A-TSN with interrupts disabled during the critical section: offset: min -26251 max 16416 mean -21.8672 std dev 863.416 delay: min 4720 max 57280 mean 5182.49 std dev 1607.19 lost servo lock 3 times Summary of the same phc2sys service running for 120 minutes with interrupts disabled: offset: min -378 max 381 mean -0.0083089 std dev 101.495 delay: min 4720 max 5920 mean 5129.38 std dev 154.899 lost servo lock 0 times The minimum delay (pre to post time) in nanoseconds is the same, but the maximum delay is quite a bit higher, due to interrupts getting sometimes executed and interfering with the measurement. Hence set disable_irqs whenever possible (aka when the driver runs in poll mode - otherwise it would be a contradiction in terms). Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Link: https://lore.kernel.org/r/20190905010114.26718-4-olteanv@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * | spi: Add a PTP system timestamp to the transfer structureVladimir Oltean2019-10-071-0/+127
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SPI is one of the interfaces used to access devices which have a POSIX clock driver (real time clocks, 1588 timers etc). The fact that the SPI bus is slow is not what the main problem is, but rather the fact that drivers don't take a constant amount of time in transferring data over SPI. When there is a high delay in the readout of time, there will be uncertainty in the value that has been read out of the peripheral. When that delay is constant, the uncertainty can at least be approximated with a certain accuracy which is fine more often than not. Timing jitter occurs all over in the kernel code, and is mainly caused by having to let go of the CPU for various reasons such as preemption, servicing interrupts, going to sleep, etc. Another major reason is CPU dynamic frequency scaling. It turns out that the problem of retrieving time from a SPI peripheral with high accuracy can be solved by the use of "PTP system timestamping" - a mechanism to correlate the time when the device has snapshotted its internal time counter with the Linux system time at that same moment. This is sufficient for having a precise time measurement - it is not necessary for the whole SPI transfer to be transmitted "as fast as possible", or "as low-jitter as possible". The system has to be low-jitter for a very short amount of time to be effective. This patch introduces a PTP system timestamping mechanism in struct spi_transfer. This is to be used by SPI device drivers when they need to know the exact time at which the underlying device's time was snapshotted. More often than not, SPI peripherals have a very exact timing for when their SPI-to-interconnect bridge issues a transaction for snapshotting and reading the time register, and that will be dependent on when the SPI-to-interconnect bridge figures out that this is what it should do, aka as soon as it sees byte N of the SPI transfer. Since spi_device drivers are the ones who'd know best how the peripheral behaves in this regard, expose a mechanism in spi_transfer which allows them to specify which word (or word range) from the transfer should be timestamped. Add a default implementation of the PTP system timestamping in the SPI core. This is not going to be satisfactory performance-wise, but should at least increase the likelihood that SPI device drivers will use PTP system timestamping in the future. There are 3 entry points from the core towards the SPI controller drivers: - transfer_one: The driver is passed individual spi_transfers to execute. This is the easiest to timestamp. - transfer_one_message: The core passes the driver an entire spi_message (a potential batch of spi_transfers). The core puts the same pre and post timestamp to all transfers within a message. This is not ideal, but nothing better can be done by default anyway, since the core has no insight into how the driver batches the transfers. - transfer: Like transfer_one_message, but for unqueued drivers (i.e. the driver implements its own queue scheduling). Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Link: https://lore.kernel.org/r/20190905010114.26718-3-olteanv@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * | spi: gpio: Look for a device node instead of matchStephen Boyd2019-10-071-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This driver doesn't do anything with the match for the device node. The logic is the same as looking to see if a device node exists or not because this driver wouldn't probe unless there is a device node match when the device is created from DT. Just test for the presence of the device node to simplify and avoid referencing a potentially undefined match table when CONFIG_OF=n. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Mark Brown <broonie@kernel.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Frank Rowand <frowand.list@gmail.com> Cc: <linux-spi@vger.kernel.org> Signed-off-by: Stephen Boyd <swboyd@chromium.org> Link: https://lore.kernel.org/r/20191004214334.149976-9-swboyd@chromium.org Signed-off-by: Mark Brown <broonie@kernel.org>
| * | spi: spi-fsl-dspi: Always use the TCFQ devices in poll modeVladimir Oltean2019-10-021-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With this patch, the "interrupts" property from the device tree bindings is ignored, even if present, if the driver runs in TCFQ mode. Switching to using the DSPI in poll mode has several distinct benefits: - With interrupts, the DSPI driver in TCFQ mode raises an IRQ after each transmitted word. There is more time wasted for the "waitq" event than for actual I/O. And the DSPI IRQ count can easily get the largest in /proc/interrupts on Freescale boards with attached SPI devices. - The SPI I/O time is both lower, and more consistently so. Attached to some Freescale devices are either PTP switches, or SPI RTCs. For reading time off of a SPI slave device, it is important that all SPI transfers take a deterministic time to complete. - In poll mode there is much less time spent by the CPU in hardirq context, which helps with the response latency of the system, and at the same time there is more control over when interrupts must be disabled (to get a precise timestamp measurement, which will come in a future patch): win-win. On the LS1021A-TSN board, where the SPI device is a SJA1105 PTP switch (with a bits_per_word=8 driver), I created a "benchmark" where I periodically transferred a 12-byte message once per second, for 120 seconds. I then recorded the time before putting the first byte in the TX FIFO, and the time after reading the last byte from the RX FIFO. That is the transfer delay in nanoseconds. Interrupt mode: delay: min 125120 max 168320 mean 150286 std dev 17675.3 Poll mode: delay: min 69440 max 119040 mean 70312.9 std dev 8065.34 Both the mean latency and the standard deviation are more than 50% lower in poll mode than in interrupt mode, and the 'max' in poll mode is lower than the 'min' in interrupt mode. This is with an 'ondemand' governor on an otherwise idle system - therefore running mostly at 600 MHz out of a max of 1200 MHz. Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Link: https://lore.kernel.org/r/20191001205216.32115-1-olteanv@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * | SPI: designware: pci: Switch over to MSI interruptsFelipe Balbi2019-10-011-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | Some devices support MSI interrupts. Let's at least try to use them in platforms that provide MSI capability. Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> Link: https://lore.kernel.org/r/20191001081405.764161-1-felipe.balbi@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * | spi: spi-fsl-qspi: Introduce variable to fix different invalid master IdKuldeep Singh2019-10-011-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Different platforms have different Master with different SourceID on AHB bus. The 0X0E Master ID is used by cluster 3 in case of LS2088A. So, patch introduce an invalid master id variable to fix invalid mastered on different platforms. Signed-off-by: Suresh Gupta <suresh.gupta@nxp.com> Signed-off-by: Kuldeep Singh <kuldeep.singh@nxp.com> Link: https://lore.kernel.org/r/1569920356-8953-1-git-send-email-kuldeep.singh@nxp.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * | spi: fsl-lpspi: clean up indentation issueColin Ian King2019-10-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | The complete call is indented incorrectly, remove the extraneous tabs. Signed-off-by: Colin Ian King <colin.king@canonical.com> Link: https://lore.kernel.org/r/20190926113701.26986-1-colin.king@canonical.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * | spi: Introduce dspi_slave_abort() function for NXP's dspi SPI driverLukasz Majewski2019-10-011-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change provides the dspi_slave_abort() function, which is a callback for slave_abort() method of SPI controller generic driver. As in the SPI slave mode the transmission is driven by master, any distortion may cause the slave to enter undefined internal state. To avoid this problem the dspi_slave_abort() terminates all pending and ongoing DMA transactions (with sync) and clears internal FIFOs. Signed-off-by: Lukasz Majewski <lukma@denx.de> Link: https://lore.kernel.org/r/20190924110547.14770-3-lukma@denx.de Signed-off-by: Mark Brown <broonie@kernel.org>
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