Each SPI controller has exactly one CS line and as such doesn't
provide for multi-cs. We implement a workaround to support
multi-cs by _not_ configuring the mux'ed CS pin for each SPI
controller. The CS mechanism is assumed to be fully machine
specific - the driver doesn't even assume some GPIO pin is used
to control the CS.
The driver selects between DMA and POLLING mode depending upon
the xfer size - DMA mode for xfers bigger than FIFO size, POLLING
mode otherwise.
The driver has been designed to be capable of running SoCs since
s3c64xx and till date, for that reason some of the register fields
have been passed via, SoC specific, platform data.
Signed-off-by: Jassi Brar <jassi.brar@samsung.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
If len > BUFFER_LEN and !xfer->rx_buf we end up calculating the tx buffer
address as
*tx_dma = xfer->tx_dma + xfer->len - BUFFER_SIZE;
which is constant; i.e. we just send the last BUFFER_SIZE data over again
until we've reached the right number of bytes.
This patch gets around this by using the /requested/ length when
calculating addresses.
Note there's no way len != *plen when we calculate the rx buffer address
but conceptually we should be using *plen and I don't want someone to come
through later, see the calculations for rx and tx are different and "clean
up" back to what we had.
Signed-off-by: Ben Nizette <bn@niasdigital.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Add pseudo-DMA by FIQ to the S3C24XX SPI driver. This allows the driver
to get DMA-like performance where there are either no free DMA channels or
when doing transfers that required both TX and RX data paths.
Since this patch requires the addition of an assembly file to hold the FIQ
code, we rename the module (instead of adding a rename of the .c file to
this patch). We expect most users are loading this via udev and thus
there should be no change to the userland configuration.
Signed-off-by: Ben Dooks <ben@simtec.co.uk>
Signed-off-by: Simtec Linux Team <linux@simtec.co.uk>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Driver for the Designware SPI core, it supports multipul interfaces like
PCI/APB etc. User can use "dw_apb_ssi_db.pdf" from Synopsys as HW
datasheet.
[randy.dunlap@oracle.com: fix build]
[akpm@linux-foundation.org: build fix]
Signed-off-by: Feng Tang <feng.tang@intel.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The driver already uses __devexit_p() in the structure, but looks like
actual __dev{init,exit} markings were forgotten.
The spidev_spi driver also needs renaming to include a "_driver" suffix to
avoid section mismatch warnings.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Probe/remove functions need to be marked as __devinit and __devexit
(not __init an __exit) to prevent trying to run code that has been
discarded. This patch fixes the spi_imx driver to mark probe and
remove correctly.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This change adds the OMAP SPI 100k driver created by
Fabrice Crohas <fcrohas@gmail.com>. This SPI bus is found on
OMAP7xx-series smartphones, and for many, the touchscreen is
attached to this bus.
The lion's share of the work was done by Fabrice on this driver --
I am merely porting it from the Linwizard project on his behalf.
Signed-off-by: Cory Maccarrone <darkstar6262@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Also there is no casting needed to assign a void pointer.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This is much safer when support for new variants is added.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
platform_get_irq returns -ENXIO if there is no entry. So ensure
return value is greater than zero instead of non-zero.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This patch is V2 of SPI Master support for the SuperH MSIOF.
Full duplex, spi mode 0-3, active high cs, 3-wire and lsb
first should all be supported, but the driver has so far
only been tested with "mmc_spi".
The MSIOF hardware comes with 32-bit FIFOs for receive and
transmit, and this driver simply breaks the SPI messages
into FIFO-sized chunks. The MSIOF hardware manages the pins
for clock, receive and transmit (sck/miso/mosi), but the chip
select pin is managed by software and must be configured as
a regular GPIO pin by the board code.
Performance wise there is still room for improvement, but
on a Ecovec board with the built-in sh7724 MSIOF0 this driver
gets Mini-sd read speeds of about half a megabyte per second.
Future work include better clock setup and merging of 8-bit
transfers into 32-bit words to reduce interrupt load and
improve throughput.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
When VERBOSE is defined in the spidev module, the compilation
will throw an error on 'spi' not being defined:
CC [M] drivers/spi/spidev.o
drivers/spi/spidev.c: In function 'spidev_message':
drivers/spi/spidev.c:266: error: 'spi' undeclared (first use in this function)
drivers/spi/spidev.c:266: error: (Each undeclared identifier is reported only once
drivers/spi/spidev.c:266: error: for each function it appears in.)
instead of using spi-> we should actually use spidev->spi.
This patch fixes the build failure.
Signed-off-by: Florian Fainelli <ffainelli@freebox.fr>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
fix setupxfer() not to override generic configuration of speed_hz
and bits_per_word with zeros
Signed-off-by: Jan Nikitenko <jan.nikitenko@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The function plat_mpc8xxx_spi_remove is defined using __devexit, so don't
use __exit_p but __devexit_p to wrap it.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
i.MX35-provided chipselects are represented using negative numbers. If
gpio_request() fails and the previous chipselect was a negative number,
the while loop is endless (i is never decremented).
Also, the error loop would never call gpio_free on chipselect[0].
And finally, the error message was missing an endline.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
On the MX31litekit, the bootloader seems to communicate with the MC13783
PMIC chip before booting Linux. However, it does not flush all the
buffers properly after that, which makes the imx-spi driver read
bogus data when probing the MC13783.
Fix that by draining the SPI receive buffer on startup.
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This patch fixes the error exposed by the following build warning:
drivers/spi/xilinx_spi.c: In function 'xilinx_spi_init':
drivers/spi/xilinx_spi.c:411: warning: cast from pointer to integer
of different size
Fixed by change %x to %p in the format string.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This patch adds in a platform device driver using the xilinx_spi common module.
Tested-by: John Linn <John.Linn@xilinx.com>
Signed-off-by: Richard Röjfors <richard.rojfors@mocean-labs.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This patch adds in support for the DS570 IP.
It's register compatible with the DS464, but adds support for 8/16/32 SPI.
The 8/16/32 support is added by attaching callbacks reading/writing the
proper amount of data. To indicate to the driver which amount of bits
to use a new field is introduced in the platform data struct.
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: John Linn <John.Linn@xilinx.com>
Signed-off-by: Richard Röjfors <richard.rojfors@mocean-labs.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This patch changes the out_(be)(8|16|32) and in_(be)(8|16|32) calls to 32 bits ioread/iowrite.
The read and write function are attached to the internal struct as callbacks, callback
is selected depending on endianess.
This will also build on platforms not supporting the in/out calls for instance x86.
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: John Linn <John.Linn@xilinx.com>
Signed-off-by: Richard Röjfors <richard.rojfors@mocean-labs.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This patch splits the xilinx_spi driver into a generic part and a
OF driver part.
The reason for this is to later add in a platform driver as well.
Tested-by: John Linn <John.Linn@xilinx.com>
Signed-off-by: Richard Röjfors <richard.rojfors@mocean-labs.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This one enables the mpc52xx_spi driver for usage of user defined gpio lines
as chipselect. This way we can control some more spi devices than only one
V2 Changes:
* preinitialize the gpio as output in probe function and call gpio_set_value in
the chip select function instead of calling direction_output every time.
* initialize the gpio line with output high, since we don't support CS_HIGH
in the driver currently any way. change gpio value setting to default active
low in chip select call.
* free the gpio array while error or removing.
Signed-off-by: Luotao Fu <l.fu@pengutronix.de>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Before reading status register to check MODF failure, we have to clear it
first since the MODF flag will be set after initializing the spi master,
if the hardware comes up with a low SS. The processor datasheet reads:
Mode Fault flag -- bit sets if SS input goes low while SPI is configured as a
master. Flag is cleared automatically by an SPI status register read (with MODF
set) followed by a SPI control register 1 write.
Hence simply rereading the register is not sufficient to clear the flag. We
redo the write also to make sure to clear the flag.
V2 Changes:
* change variable type from int to u8
Signed-off-by: Luotao Fu <l.fu@pengutronix.de>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
To easily identify which device has problems.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The bits_per_word value can be set for each transfer, or can
be set to zero in each transfer in which case it should default
to the value in the driver.
The driver was fixed to properly check the bits_per_word in
the transfer that is passed in.
Signed-off-by: John Linn <john.linn@xilinx.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This driver calls mpc52xx_set_psc_clkdiv() but doesn't check its return value
to see if the PSC is actually valid for SPI use. Add the check and a hint for
the user.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Add call to of_register_spi_devices() to register SPI devices described
in the OF device tree.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
This fixes the wrong peripheral id being
used in pl022 driver for ST derivative.
Signed-off-by: srinidhi kasagar <srinidhi.kasagar@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
spi_imx_chipselect() made things that should be (and mostly are) done by
spi_imx_setupxfer. Only setting the tx and rx functions was missing.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Otherwise the config function uses random data from the stack. This
didn't stick out because config is called once more in the chipselect
function with correct parameters.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
spi_imx_setup() is only called by spi_setup(). The latter does the
initialization already.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We can only setup the gpio pins in spi_setup time when we know the
SPI_CS_HIGH setting.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This makes the filename match the Kconfig symbol and the driver name.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Support two new half-duplex SPI implementation restrictions, for links
that talk to TX-only or RX-only devices. (Existing half-duplex flavors
support both transfer directions, just not at the same time.)
Move spi_async() into the spi.c core, and stop inlining it. Then make
that function perform error checks and reject messages that demand more
than the underlying controller can support.
Based on a patch from Marek Szyprowski which did this only for the
bitbanged GPIO driver.
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
tAdd adds McSPI support for OMAP4430 SDP platform. All the base addresses
are changed between OMAP1/2/3 and OMAP4. The fields of the resource
structures are filled at runtime to have McSPI support on OMAP4.
Signed-off-by: Syed Rafiuddin <rafiuddin.syed@ti.com>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Previous restore was lazy and only restored CHxCONF when it was needed by
a specific chip select. This could cause occasional errors on an SPI bus
where multiple chip selects are in use.
Signed-off-by: Tero Kristo <tero.kristo@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With the update to the spi_bitbang driver, the transfer setup code is
being called more often, and thus is often re-doing calculations that have
been done before. The SPI layer allows our driver to add its own data to
each device so add a result cache to each device.
This should also remove the problem where we where directly setting up
registers in the setup call which meant we might overwrite the state of an
extant transfer.,
Signed-off-by: Ben Dooks <ben@simtec.co.uk>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>