The user must read N bytes of SPIRF (1 <= N <= 4) that do not exceed the
amount of data in the receive FIFO, so read the SPIRF byte by byte when
the data in receive FIFO is less than 4 bytes.
On Simics, when read N bytes that exceed the amout of data in receive
FIFO, we can't read the data out, that is we can't clear the rx FIFO,
then the CPU will loop on the espi rx interrupt.
Signed-off-by: Mingkai Hu <Mingkai.hu@freescale.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
* 'spi' of git://git.linutronix.de/users/bigeasy/soda into spi/next
spi/pxa2xx: register driver properly
spi/pxa2xx: add support for shared IRQ handler
spi/pxa2xx: Use define for SSSR_TFL_MASK instead of plain numbers
arm/pxa2xx: reorgazine SSP and SPI header files
spi/pxa2xx: Add CE4100 support
spi/pxa2xx: Consider CE4100's FIFO depth
spi/pxa2xx: Add chipselect support for Sodaville
spi/pxa2xx: Modify RX-Tresh instead of busy-loop for the remaining RX bytes.
spi/pxa2xx: pass of_node to spi device and set a parent device
* 'for-grant' of git://arago-project.org/git/projects/linux-davinci into spi/next
spi: davinci: fix checkpatch errors
spi: davinci: whitespace cleanup
spi: davinci: remove unused variable 'pdata'
spi: davinci: set chip-select mode in SPIDEF only once
spi: davinci: enable both activation and deactivation of chip-selects
spi: davinci: remove unnecessary data transmit on CS disable
spi: davinci: enable GPIO lines to be used as chip selects
spi: davinci: simplify prescalar calculation
spi: davinci: remove 'wait_enable' platform data member
spi: davinci: make chip-slect specific parameters really chip-select specific
spi: davinci: consolidate setup of SPIFMTn in one function
spi: davinci: setup chip-select timers values only if timer enabled
spi: davinci: add support for wait enable timeouts
spi: davinci: remove unused members of davinci_spi_slave
spi: davinci: eliminate the single member structure davinci_spi_slave
spi: davinci: eliminate unnecessary update of davinci_spi->count
spi: davinci: simplify calculation of edma acount value
spi: davinci: check for NULL buffer pointer before using it
spi: davinci: remove unnecessary disable of SPI
spi: davinci: remove unnecessary 'count' variable in driver private data
spi: davinci: remove unnecessary completion variable initialization
spi: davinci: remove non-useful interrupt mode support
spi: davinci: simplify poll mode transfers
spi: davinci: add support for interrupt mode
spi: davinci: configure the invariable bits in spipc0 only once
spi: davinci: remove unnecessary function davinci_spi_bufs_prep()
spi: davinci: remove unnecessary call to davinci_spi_setup_transfer()
spi: davinci: do not store DMA channel information per chip select
spi: davinci: always start transmit DMA
spi: davinci: do not use temporary buffer if no transmit data provided
spi: davinci: always start receive DMA
spi: davinci: use edma_write_slot() to setup EDMA PaRAM slot
spi: davinci: fix DMA event generation stoppage
spi: davinci: fix EDMA CC errors at end of transfers
spi: davinci: handle DMA completion errors correctly
spi: davinci: remove usage of additional completion variables for DMA
spi: davinci: let DMA operation be specified on per-device basis
spi: davinci: remove non-useful "clk_internal" platform data
spi: davinci: enable and power-up SPI only when required
spi: davinci: setup the driver owner
spi: davinci: add additional comments
spi: davinci: add EF Johnson Technologies copyright
spi: davinci: removed unused #defines
spi: davinci: remove unnecessary typecast
spi: davinci: do not treat Tx interrupt being set as error
spi: davinci: do not allocate DMA channels during SPI device setup
spi: davinci: remove unnecessary private data member 'region_size'
spi: davinci: shorten variable names
spi: davinci: kconfig: add manufacturer name to prompt string
Probe/remove should be in __devinit/__devexit. Found by a section-mismatch
warning. Also, copy do_remove() over to remove().
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
dw_spi driver in upstream only supports PIO mode, and this patch
will support it to cowork with the Designware dma controller used
on Intel Moorestown platform, at the same time it provides a general
framework to support dw_spi core to cowork with dma controllers on
other platforms
It has been tested with a Option GTM501L 3G modem and Infenion 60x60
modem. To use DMA mode, DMA controller 2 of Moorestown has to be enabled
Also change the dma interface suggested by Linus Walleij.
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Feng Tang <feng.tang@intel.com>
[Typo fix and renames to match intel_mid_dma renaming]
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The SPI polling loop timeout only works with HZ=100 as the loop was
actually too short.
Also add appropriate cpu_relax() in the busy wait loops...
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This variable is a bool but defined an int and defined completely
backwards. This makes the code more readable.
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The sglen return by the dma_map_sg() should be passed to the DMA
engine, not the one passed in. If we one day have a DMA mapper
that can coalesce entries, this will bug due to a too large
number of entries being passed in.
Reported-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The struct device for the DMA engine is the apropriate one to use
when mapping/unmapping buffers. This is because the memory which
is addressable by DMA is determined by the DMA engine rather than
the device.
Reported-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
It seems spi_topcliff_pch of linux-2.6.37-rc6 degraded by previous patch.
In fact, data transfer fails on evaluation board testing.
I found like the following register miss-setting line.
Using this patch, I have confirmed data transfer can work well.
Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
There are no machines in-tree that still use the driver
name as device name. So save a few bytes and remove it.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Jason Wang <jason77.wang@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
There is a possibility that the last word of a transaction will be lost
if data is not ready. Re-read in poll_transfer() to solve this issue
when poll_mode is enabled.
Verified on SPI touch screen device.
Signed-off-by: Major Lee <major_lee@wistron.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After all TX bytes are sent, the driver spins while the SPI core is busy
and then it spins for a "short" period of time until RX bytes are
available.
On Sodavile the busy flag disappears pretty quick and after that it
takes approx ~130ms (sometimes less but not much) until there are bytes
available in the RX FIFO.
This patch removes the busy loop and modifies the RX threshould so we
get woken up once the remainings bytes arrived.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
The SPI core on Sodaville supports chip selects. Its configuration
moved into the SSSR register at bit 0 and 1. Thus Sodaville can be hooked
up with up to 4 devices.
This patch ensures that the bits which are otherwiese reserved are only
touched on Sodaville and not on any other PXAs. Also it makes sure that
the status register does not lose the CS information while clearing the
ROR bit.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
For PXA the default threshold is FIFO_DEPTH / 2. Adjust this value for
CE4100.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
Sodaville's SPI controller is very much the same as in PXA25x. The
difference:
- The RX/TX FIFO is only 4 words deep instead of 16
- No DMA support
- The SPI controller offers a CS functionality
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
The PXA-SPI driver relies on some files / defines which are arm specific
and are within the ARM tree. The CE4100 SoC which is x86 has also the
SPI core.
This patch moves the ssp and spi files from arm/mach-pxa and plat-pxa to
include/linux where the CE4100 can access them.
This move got verified by building the following defconfigs:
cm_x2xx_defconfig corgi_defconfig em_x270_defconfig ezx_defconfig
imote2_defconfig pxa3xx_defconfig spitz_defconfig zeus_defconfig
raumfeld_defconfig magician_defconfig
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
This is required in case the interrupt line is shared with other
devices.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
passing argument 2 of 'dma_map_single' discards qualifiers from pointer target type
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
use platform_driver_register instead of platform_driver_probe. The
latter only checks available devices at the time of calling. So if a
device gets inserter at a later point in time then the driver will never
play with it.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
Add manufacturer name to the Kconfig prompt string and move
the controller name to the begining of the prompt.
This helps locate the driver easily among the list of existing
drivers.
While at it, also add information about being able to build
the driver as module.
Tested-By: Brian Niebuhr <bniebuhr@efjohnson.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Shorten names of local variables and structure members where
possible.
Local variables:
* 'davinci_spi' is being renamed 'dspi'
* 'davinci_spi_dma' is being renamed 'dma'
Structure members:
* 'dma_{tx|rx}_channel' is being renamed '{tx|rx}_channel'
since the structure containing them is already called
'davinci_spi_dma'
* 'davinci_spi_dma' in 'davinci_spi' structure is being
renamed 'dma'
Tested-By: Brian Niebuhr <bniebuhr@efjohnson.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Remove unnecesary private data member 'region_size'
being used to store the size of SPI memory region.
Instead, get the memory resource size directly from
the platform data.
Tested-By: Brian Niebuhr <bniebuhr@efjohnson.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Add copyright for EF Johnson Technologies since the driver
has been majorly overhauled by Brian.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Add comments describing the platform data members
and per-chip-select SPI configuration structure.
Also, add some comments describing the what happens
during the driver probe.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Setup the owner member of the platform driver to THIS_MODULE
instead of leaving it NULL.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Enable SPI only when active transfers are in progress. Keep
it in local low power when not in use.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
The "clk_internal" platform data member which contols the
CLKMOD bit in Global Control Register 1 is not useful
since CLKMOD needs be set to 1 *always* to ensure master
mode operation.
Remove this platform data.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Let DMA operation be specified on a per-device basis instead
of selecting it once during probe.
A side effect of this is the need to combine the PIO and DMA buffer
txrx_bufs routine. This is good since they anyway share some common
functionality.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
The DMA code does not use the existing completion variable 'done'
which is being used for interrupt mode transfers. Instead it uses
two different completion variables specific to DMA mode transfers.
Eliminate the usage of new completion variables for DMA mode and
use the existing completion variable.
[nsekhar@ti.com: To make this process easy, eliminate the two
different DMA completion callback functions for tx and rx and
use a single callback function instead]
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Do not simply clean the DMA channel on a DMA completion
error. Instead, use wcount and rcount members of davinci_spi
to detecion non-completion of DMA and signal EIO to the
application.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Use a dummy param slot linked to itself to take care of the
extra "sync event" that gets sent to EDMA controller after
the last byte has been transferred.
The dummy PaRAM slot that is linked to the actual DMA PaRAM
slot "absorbs" this event and prevents a EDMA CC error to
be asserted.
Without this provision, the EDMA CC error would be asserted
because the channel PaRAM would be empty after the transfer
and EDMA would not know what to make out of the extra sync
event.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Do not allocate (and de-allocate) SPI DMA channels during setup
(and cleanup) for each SPI device. Instead, allocate the DMA
channels once duing probe and use them for the life time of
the driver.
This makes sense since there are dedicated DMA channels meant
for SPI use.
This also helps remove the unnecessary DMA "sync_dev" variables
being used to store DMA channel information.
Also, the "use_dma" platform variable is now eliminated since
it is possible to check if the platform supports DMA or not
based upon whether DMA resources can be found or not.
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Tested-By: Brian Niebuhr <bniebuhr@efjohnson.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Do not stop SPI DMA event generation in either transmit or
receive DMA event call back because the single setting affects
both transmit and receive event generation.
Depending on the order in which the callbacks happen, transmit
or receive events can get unintentionally stalled.
Instead, disable event generation once after both the transmit
and receive DMA completes.
While at it, remove the largely under-used function to set or
clear DMA event generation.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Currently a series of EDMA API calls are being made to setup
various aspects of EDMA PaRAM slots for receive and transmit.
Instead setup the PaRAM using a local structure and write once
to the hardware using edma_write_slot()
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
In keeping with the full duplex nature of the SPI bus. Always
start receive DMA along with transmit DMA.
If there is no receive buffer provided with the transfer, use
a temporary buffer to receive the data to be thrown away.
[michael.williamson@criticallink.com: receive DMA size should
be same as transfer length to avoid hang-up when transfer length
is smaller than temporary rx buffer size (rx buffer not provided)]
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Remove usage of temporary buffer when no transmit data is provided.
Instead, use the transmit register itself as the source of data.
By choosing the transmit register itself as the source of data, this
patch helps remove unnecessary accesses to memory when no real data
is being transmitted.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Due to the full duplex nature of the SPI bus, the SPI master
on DaVinci needs transmit to be active even if the tranfer is
only meant to collect receive data.
The current code achieves this by using a temporary zeroed buffer
to provide DMA data in case the transfer does not have a transmit
buffer provided.
However, the transmit DMA is started only if transmit buffer is
provided rendering the temporary buffer unused. Instead the code
relies on a write to SPIDAT1 register to trigger transmit operation.
This however only sends two bytes of data.
Fix this by starting transmit DMA always.
This changes exposes a bug on DM355 where the CSHOLD bit in
SPIDAT1 needs to be written to in between transfers. Handle
that by introducing a "cshold_bug" platform data which is
set to true for DM355.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Do not store DMA channel related information per chip-select since
that information does not depend on the chip select.
The same DMA channels can be used for transfers on all chip-selects
since the transfer happens one-at-a-time.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Remove unnecessary call to davinci_spi_setup_transfer() at the end
of davinci_spi_setup().
davinci_spi_setup_transfer() is registered as the setup_transfer
callback for the bitbang layer and is called independently by
the bitbang layer to setup the transfer before it begins.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
The function davinci_spi_bufs_prep() is doing stuff that
davinci_spi_setup() is doing. Eliminate it and move the work
to davinci_spi_setup()
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Configure the data-in, data-out and clock functionality pins
in SPIPC0 register only once during probe. No need to set these
bits for each transfer.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Add support for SPI interrupt mode operation.
Define a per chip-select "io type" variable which
specifies if the transfers on this chip-select should
happen in interrupt mode or polled mode.
Introduce a new function davinci_spi_process_events()
to help consolidate the code between interrupt mode
processing and polled mode processing.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Use the fact that the get_tx and get_rx can now cope with
NULL buffer pointers to simplify the poll mode transfer
code.
While at it, check for SPI errors every transfer rather than
at the end of the whole transfer.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
