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path: root/drivers/spi/designware_spi.c
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2018-05-07SPDX: Convert all of our single license tags to Linux Kernel styleTom Rini
When U-Boot started using SPDX tags we were among the early adopters and there weren't a lot of other examples to borrow from. So we picked the area of the file that usually had a full license text and replaced it with an appropriate SPDX-License-Identifier: entry. Since then, the Linux Kernel has adopted SPDX tags and they place it as the very first line in a file (except where shebangs are used, then it's second line) and with slightly different comment styles than us. In part due to community overlap, in part due to better tag visibility and in part for other minor reasons, switch over to that style. This commit changes all instances where we have a single declared license in the tag as both the before and after are identical in tag contents. There's also a few places where I found we did not have a tag and have introduced one. Signed-off-by: Tom Rini <trini@konsulko.com>
2018-04-23spi: dw: invert wait condition in dw_spi_xferEugeniy Paltsev
While switching to readl_poll_timeout macros from custom code the waiting condition was accidently inverted, so it was pure luck that this code works at least in some conditions. Fix that by inverting exit condition for readl_poll_timeout. Fixes: c6b4f031d9 ("DW SPI: fix tx data loss on FIFO flush") Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Reviewed-by: Jagan Teki <jagan@openedev.com>
2018-03-22DW SPI: use 32 bit access instead of 16 and 32 bit mixEugeniy Paltsev
Current DW SPI driver uses 32 bit access for some registers and 16 bit access for others. So if DW SPI IP is connected via bus which doesn't support 16 bit access we will get bus error. Fix that by switching to 32 bit access only instead of 16 and 32 bit mix Additional Documentation to Support this Change: The DW_apb_ssi databook states: "All registers in the DW_apb_ssi are addressed at 32-bit boundaries to remain consistent with the AHB bus. Where the physical size of any register is less than 32-bits wide, the upper unused bits of the 32-bit boundary are reserved. Writing to these bits has no effect; reading from these bits returns 0." [1] [1] Section 6.1 of dw_apb_ssi.pdf (version 3.22a) Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Reviewed-by: Jagan Teki <jagan@openedev.com>
2018-03-22DW SPI: add option to use external gpio for chip selectEugeniy Paltsev
DW SPI internal chip select management has limitation: it hold CS line in active state only when the FIFO is not empty. If the FIFO freed before we add new data the SPI transaction will be broken. So add option to use external gpio for chip select. Gpio can be added via device tree using standard gpio bindings. Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Reviewed-by: Jagan Teki <jagan@openedev.com>
2018-03-22DW SPI: refactor poll_transfer functionsEugeniy Paltsev
There is no sense in waiting for RX data in dw_reader function: there is no chance that RX data will appear in RX FIFO if RX FIFO is empty after previous TX write in dw_writer function. So get rid of this waiting. After that we can get rid of dw_reader return value and make it returning void. After that we can get rid of dw_reader return value check in poll_transfer function. With these changes we're getting closer to Linux DW SPI driver. Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Reviewed-by: Jagan Teki <jagan@openedev.com>
2018-03-22DW SPI: fix transmit only modeEugeniy Paltsev
In current implementation we get -ETIMEDOUT error when we try to use transmit only mode (SPI_TMOD_TO) This happens because in transmit only mode input FIFO never gets any data which breaks our logic in dw_reader(): we are waiting until RX data will be ready in dw_reader, but this newer happens, so we return with error. Fix that by using SPI_TMOD_TR instead of SPI_TMOD_TO which allows to use RX FIFO. Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Reviewed-by: Jagan Teki <jagan@openedev.com>
2018-03-22DW SPI: fix tx data loss on FIFO flushEugeniy Paltsev
In current implementation if some data still exists in Tx FIFO it can be silently flushed, i.e. dropped on disabling of the controller, which happens when writing 0 to DW_SPI_SSIENR (it happens in the beginning of new transfer) So add wait for current transmit operation to complete to be sure that current transmit operation is finished before new one. Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Reviewed-by: Jagan Teki <jagan@openedev.com>
2018-01-26DW SPI: Get clock value from Device TreeEugeniy Paltsev
Add option to set spi controller clock frequency via device tree using standard clock bindings. Define dw_spi_get_clk function as 'weak' as some targets (like SOCFPGA_GEN5 and SOCFPGA_ARRIA10) don't use standard clock API and implement dw_spi_get_clk their own way in their clock manager. Get rid of clock_manager.h include as we don't use cm_get_spi_controller_clk_hz function anymore. (we use redefined dw_spi_get_clk in SOCFPGA clock managers instead) Reviewed-by: Marek Vasut <marex@denx.de> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Reviewed-by: Jagan Teki <jagan@openedev.com>
2017-06-01dm: Rename dev_addr..() functionsSimon Glass
These support the flat device tree. We want to use the dev_read_..() prefix for functions that support both flat tree and live tree. So rename the existing functions to avoid confusion. In the end we will have: 1. dev_read_addr...() - works on devices, supports flat/live tree 2. devfdt_get_addr...() - current functions, flat tree only 3. of_get_address() etc. - new functions, live tree only All drivers will be written to use 1. That function will in turn call either 2 or 3 depending on whether the flat or live tree is in use. Note this involves changing some dead code - the imx_lpi2c.c file. Signed-off-by: Simon Glass <sjg@chromium.org>
2017-02-08dm: core: Replace of_offset with accessorSimon Glass
At present devices use a simple integer offset to record the device tree node associated with the device. In preparation for supporting a live device tree, which uses a node pointer instead, refactor existing code to access this field through an inline function. Signed-off-by: Simon Glass <sjg@chromium.org>
2015-10-27spi: designware_spi: Use GENMASKJagan Teki
Replace numeric mask hexcodes with GENMASK macro in designware_spi Cc: Stefan Roese <sr@denx.de> Cc: Marek Vasut <marex@denx.de> Reviewed-by: Tom Rini <trini@konsulko.com> Signed-off-by: Jagan Teki <jteki@openedev.com>
2015-10-27spi: designware_spi: Use BIT macroJagan Teki
Replace numerical bit shift with BIT macro in designware_spi :%s/(1 << nr)/BIT(nr)/g where nr = 0, 1, 2 .... 31 Cc: Stefan Roese <sr@denx.de> Cc: Marek Vasut <marex@denx.de> Reviewed-by: Tom Rini <trini@konsulko.com> Signed-off-by: Jagan Teki <jteki@openedev.com>
2015-08-31dm: Use dev_get_addr() where possibleSimon Glass
This is a convenient way for a driver to get the hardware address of a device, when regmap or syscon are not being used. Change existing callers to use it as an example to others. Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Joe Hershberger <joe.hershberger@ni.com> Acked-by: Stephen Warren <swarren@wwwdotorg.org>
2015-03-30spi: designware_spi: revisit FIFO size detection againAxel Lin
By specification the FIFO size would be in a range 2-256 bytes. From TX Level prospective it means we can set threshold in the range 0-(FIFO size - 1) bytes. Hence there are currently two issues: a) FIFO size 2 bytes is actually skipped since TX Level is 1 bit and could be either 0 or 1 byte; b) FIFO size is incorrectly decreased by 1 which already done by meaning of TX Level register. Fixes: 501943696ea4 (spi: designware_spi: Fix detecting FIFO depth) Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Axel Lin <axel.lin@ingics.com> Acked-by: Pavel Machek <pavel@denx.de> Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2015-01-29dm: spi: Move the per-child data size to the uclassSimon Glass
This is common to all SPI drivers and specifies a structure used by the uclass. It makes more sense to define it in the uclass. Reviewed-by: Masahiro Yamada <yamada.m@jp.panasonic.com> Signed-off-by: Simon Glass <sjg@chromium.org>
2015-01-06dt: socfpga: Rename snps, dw-spi-mmio to snps, dw-apb-ssiMarek Vasut
Linux now also contains SPI driver, yet the name is 'snps,dw-apb-ssi'. Fix the naming before we have to support both names. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Chin Liang See <clsee@opensource.altera.com> Cc: Dinh Nguyen <dinguyen@opensource.altera.com> Cc: Pavel Machek <pavel@denx.de> Cc: Stefan Roese <sr@denx.de> Cc: Vince Bridgers <vbridger@opensource.altera.com> Reviewed-by: Stefan Roese <sr@denx.de> Acked-by: Pavel Machek <pavel@denx.de> Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2015-01-06spi: designware_spi: Fix detecting FIFO depthAxel Lin
Current code tries to find the highest valid fifo depth by checking the value it wrote to DW_SPI_TXFLTR. There are a few problems in current code: 1) There is an off-by-one in dws->fifo_len setting because it assumes the latest register write fails so the latest valid value should be fifo - 1. 2) We know the depth could be from 2 to 256 from HW spec, so it is not necessary to test fifo == 257. In the case fifo is 257, it means the latest valid setting is fifo = 256. So after the for loop iteration, we should check fifo == 2 case instead of fifo == 257 if detecting the FIFO depth fails. This patch fixes above issues. Signed-off-by: Axel Lin <axel.lin@ingics.com> Acked-by: Stefan Roese <sr@denx.de> Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2014-12-06spi: designware_spi: Some fixes / changesStefan Roese
As suggested by Pavel, here some fixes to the designware SPI driver: - Spelling fixes - Comment for timeout added - Removed n_bytes completely (bits_per_word is enough for this) - Unput clock now not defined via macro. The function to get the clock value is now called directly from within the driver Signed-off-by: Stefan Roese <sr@denx.de> Cc: Chin Liang See <clsee@altera.com> Cc: Dinh Nguyen <dinguyen@altera.com> Cc: Vince Bridgers <vbridger@altera.com> Cc: Marek Vasut <marex@denx.de> Acked-by: Pavel Machek <pavel@denx.de> Cc: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2014-12-06spi: Add designware master SPI DM driver used on SoCFPGAStefan Roese
This patch adds the driver for the Designware master SPI controller. This IP core is integrated on the Altera SoCFPGA. This implementation is a driver model (DM) implementation. So multiple SPI drivers can be used. Thats necessary, since SoCFPGA also integrates the Cadence QSPI controller used to connect the SPI NOR flashes. Without DM, using multiple SPI drivers is not possible. This driver is very loosely based on the Linux driver. Most of the Linux driver is removed. Only the polling loop for the transfer is really used from this driver, as we don't support interrupts and DMA right now. This is tested on the SoCrates SoCFPGA board using the SPI pins on the P14 header. Signed-off-by: Stefan Roese <sr@denx.de> Cc: Chin Liang See <clsee@altera.com> Cc: Dinh Nguyen <dinguyen@altera.com> Cc: Vince Bridgers <vbridger@altera.com> Cc: Marek Vasut <marex@denx.de> Cc: Pavel Machek <pavel@denx.de> Reviewed-by: Simon Glass <sjg@chromium.org> Cc: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>