Commit Graph

19 Commits

Author SHA1 Message Date
Michael van der Westhuizen c4fe57f762 spi: dw: Allow interface drivers to limit data I/O to word sizes
The commit dd11444327 ("spi: dw-spi: Convert 16bit accesses to 32bit
accesses") changed all 16bit accesses in the DW_apb_ssi driver to 32bit.
This, unfortunately, breaks data register access on picoXcell, where the
DW IP needs data register accesses to be word accesses (all other
accesses appear to be OK).

This change introduces a new master variable to allow interface drivers
to specify that 16bit data transfer I/O is required.  This change also
introduces the ability to set this variable via device tree bindings in
the MMIO interface driver.  Both the core and the MMIO interface driver
default to the current 32bit behaviour.

Before this change, on a picoXcell pc3x3:
 spi_master spi32766: interrupt_transfer: fifo overrun/underrun
 m25p80 spi32766.0: error -5 reading 9f
 m25p80: probe of spi32766.0 failed with error -5

After this change:
 m25p80 spi32766.0: m25p40 (512 Kbytes)

Fixes: dd11444327 ("spi: dw-spi: Convert 16bit accesses to 32bit accesses")
Signed-off-by: Michael van der Westhuizen <michael@smart-africa.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-08-21 10:25:28 -07:00
Thor Thayer dd11444327 spi: dw-spi: Convert 16bit accesses to 32bit accesses
Altera's Arria10 SoC interconnect requires a 32-bit write for APB
peripherals. The current spi-dw driver uses 16-bit accesses in
some locations. This patch converts all the 16-bit reads and
writes to 32-bit reads and writes.

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)

Request for test with platforms using the DesignWare SPI IP.

Tested On:
Altera CycloneV development kit
Altera Arria10 development kit
Compile tested for build errors on x86_64 (allyesconfigs)

Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Reviewed-and-tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-03-17 12:27:09 +00:00
Andy Shevchenko d744f82683 spi: dw-mid: convert to use dw_dmac instead of intel_mid_dma
intel_mid_dma seems to be unmaintained for a long time. Moreover, the IP block
of DMA itself is the same in both dw_dmac and intel_mid_dma. This patch moves
spi-dw-midpci to use dw_dmac driver.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-03-09 18:11:13 +00:00
Andy Shevchenko f89a6d8f43 spi: dw-mid: move to use core SPI DMA mappings
SPI core has a comprehensive function set to map and unmap a message when it's
needed. This patch converts driver to use that advantage.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-03-09 18:11:13 +00:00
Andy Shevchenko 4d5ac1edfd spi: dw-mid: clear ongoing DMA transfers on timeout
This patch shuts up any ongoing DMA transfer in case of error.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-03-09 18:11:13 +00:00
Andy Shevchenko 9f14538ecd spi: dw-mid: split dma_setup() from dma_transfer()
The patch splits DMA preparatory code to dma_setup() callback. The change also
converts transfer_one() to program DMA whenever the transfer is DMA mapped. The
change is a follow up of the converion to use SPI core transfer_one_message().
Since the DMA mapped transfers can be interleaved with PIO ones the DMA related
configuration should respect that.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-03-09 18:11:13 +00:00
Andy Shevchenko c22c62db3f spi: dw: move to SPI core message handling
This patch removes a lot of duplicate code since SPI core provides a nice
message handling.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-03-06 20:33:38 +00:00
Andy Shevchenko 45746e82cf spi: dw: make sure SPI controller is enabled
The error handling is partially broken since the controller is disabled on
error and is not re-enabled until condition occurs, i.e. mode (poll, PIO/DMA),
chip (cs_change), or speed (clk_div) is changed. In the result of these changes
we will have a predictable state of the SPi controller independently on how
successfull was a previous transfer.

The patch disables interrupts and re-enables the SPI controller wherever it
needs to be done. Thus most of the time the SPI controller is kept enabled. The
runtime PM, when it will be implemented, must take care of the controller
disabling and re-enabling.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-03-06 20:29:03 +00:00
Andy Shevchenko 30c8eb52cc spi: dw-mid: split rx and tx callbacks when DMA
Currently driver wouldn't work properly if user asked for simplex transfer. The
patch separates DMA rx and tx callbacks and finishes transfer correctly in any
case.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2014-10-28 22:40:38 +00:00
Andy Shevchenko 15ee3be78b spi: dw-mid: change magic numbers to the constants
Instead of using magic numbers in the code we create a bit map definition of
the DMACR register and use it.

There is no functional change.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2014-10-02 17:06:26 +01:00
Andy Shevchenko b89e9c87dd spi: dw-mid: remove redundant dmac member
Instead of using that member we prefer to use dma_dev which represents actual
struct device of the DMA device.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2014-09-13 17:01:57 +01:00
Andy Shevchenko 05ed2aee3e spi: dw: remove FSF address
There is no need to keep FSF address in the head of the file. While here, fix
few typos in the header.

There is no functional change.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2014-09-13 17:01:56 +01:00
Baruch Siach d9c73bb8a3 spi: dw: add support for gpio controlled chip select
Also, use this opportunity to let spi_chip_sel() handle chip-select
deactivation as well.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-04-24 18:09:05 +01:00
Baruch Siach ec37e8e1f0 spi: dw: migrate to generic queue infrastructure
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-04-24 18:01:05 +01:00
Baruch Siach 04f421e7b0 spi: dw: use managed resources
Migrate mmio code and core driver to managed resources to reduce boilerplate
error handling code. Also, handle clk_enable() failure while at it, and drop
unused dw_spi iolen field.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-12-31 12:30:18 +00:00
Baruch Siach 0a47d3c404 spi: dw: drop unused struct dw_spi field
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-12-30 13:18:09 +00:00
H Hartley Sweeten 7eb187b3cd spi: spi-dw: fix all sparse warnings
The dw_{read,write}[lw] macros produce sparse warnings everytime they
are used.  The "read" ones cause:

warning: cast removes address space of expression
warning: incorrect type in argument 1 (different address spaces)
   expected void const volatile [noderef] <asn:2>*addr
   got unsigned int *<noident>

And the "write" ones:

warning: cast removes address space of expression
warning: incorrect type in argument 2 (different address spaces)
   expected void volatile [noderef] <asn:2>*addr
   got unsigned int *<noident>

Fix this by removing struct dw_spi_reg and converting all the register
offsets to #defines. Then convert the macros into inlined functions so
that proper type checking can occur.

While here, also fix the three sparse warnings in spi-dw-mid.c due to
the return value of ioremap_nocache being stored in a u32 * not a
void __iomem *.

With these changes the spi-dw* files all build with no sparse warnings.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-09-21 09:41:48 -06:00
Liu, ShuoX 40bfff85ff spi/dw: Add spi number into spi irq desc
Signed-off-by: ShuoX Liu <shuox.liu@intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-07-08 13:09:00 -06:00
Grant Likely ca632f5566 spi: reorganize drivers
Sort the SPI makefile and enforce the naming convention spi_*.c for
spi drivers.

This change also rolls the contents of atmel_spi.h into the .c file
since there is only one user of that particular include file.

v2: - Use 'spi-' prefix instead of 'spi_' to match what seems to be
      be the predominant pattern for subsystem prefixes.
    - Clean up filenames in Kconfig and header comment blocks

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
2011-06-06 01:16:30 -06:00