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>
Remove the old WDT implementation.
Signed-off-by: Albrecht Dreß <albrecht.dress@arcor.de>
Acked-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Merge the WDT code into the GPT interface.
Signed-off-by: Albrecht Dreß <albrecht.dress@arcor.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Add the "fsl,wdt-on-boot" OF property as to reserve a GPT as WDT which may
be a requirement in safety-related (e.g. ISO/EN 61508) applications.
Signed-off-by: Albrecht Dreß <albrecht.dress@arcor.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This patch changes the period parameter of mpc52xx_gpt_start_timer to
a u64 to support larger timeout periods.
Signed-off-by: Albrecht Dreß <albrecht.dress@arcor.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This trivial patch changes memcpy_(to|from)io as to transfer as many
32-bit words as possible in 32-bit accesses (in the current solution,
the last 32-bit word was transferred as 4 byte accesses).
Signed-off-by: Albrecht Dreß <albrecht.dress@arcor.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>
This is a driver for the FIFO device on the LocalPlus bus on an mpc5200 system.
The driver supports programmed I/O through the FIFO as well as setting up DMA
via the BestComm engine through the FIFO.
Signed-off-by: John Bonesio <bones@secretlab.ca>
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>
* 'for-linus' of git://github.com/at91linux/linux-2.6-at91:
at91: at91sam9g45 family: identify several chip versions
avr32: add two new at91 to cpu.h definition
cpu_is_xxx() macros are identifying generic at91sam9g45 chip. This patch adds
the capacity to differentiate Engineering Samples and final lots through the
inclusion of at91_cpu_fully_identify() and the related chip IDs with chip
version field preserved.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Somme common drivers will need those at91 cpu_is_xxx() definitions. As
at91sam9g10 and at91sam9g45 are on the way to linus' tree, here is the patch
that adds those chips to cpu.h in AVR32 architecture.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus: (38 commits)
MIPS: O32: Fix ppoll
MIPS: Oprofile: Rename cpu_type from godson2 to loongson2
MIPS: Alchemy: Fix hang with high-frequency edge interrupts
MIPS: TXx9: Fix spi-baseclk value
MIPS: bcm63xx: Set the correct BCM3302 CPU name
MIPS: Loongson 2: Set cpu_has_dc_aliases and cpu_icache_snoops_remote_store
MIPS: Avoid potential hazard on Context register
MIPS: Octeon: Use lockless interrupt controller operations when possible.
MIPS: Octeon: Use write_{un,}lock_irq{restore,save} to set irq affinity
MIPS: Set S-cache linesize to 64-bytes for MTI's S-cache
MIPS: SMTC: Avoid queing multiple reschedule IPIs
MIPS: GCMP: Avoid accessing registers when they are not present
MIPS: GIC: Random fixes and enhancements.
MIPS: CMP: Fix memory barriers for correct operation of amon_cpu_start
MIPS: Fix abs.[sd] and neg.[sd] emulation for NaN operands
MIPS: SPRAM: Clean up support code a little
MIPS: 1004K: Enable SPRAM support.
MIPS: Malta: Enable PCI 2.1 compatibility in PIIX4
MIPS: Kconfig: Fix duplicate default value for MIPS_L1_CACHE_SHIFT.
MIPS: MTI: Fix accesses to device registers on MIPS boards
...
* 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
PM: Remove some debug messages producing too much noise
PM: Fix warning on suspend errors
PM / Hibernate: Add newline to load_image() fail path
PM / Hibernate: Fix error handling in save_image()
PM / Hibernate: Fix blkdev refleaks
PM / yenta: Split resume into early and late parts (rev. 4)
nr_processes() returns the sum of the per cpu counter process_counts for
all online CPUs. This counter is incremented for the current CPU on
fork() and decremented for the current CPU on exit(). Since a process
does not necessarily fork and exit on the same CPU the process_count for
an individual CPU can be either positive or negative and effectively has
no meaning in isolation.
Therefore calculating the sum of process_counts over only the online
CPUs omits the processes which were started or stopped on any CPU which
has since been unplugged. Only the sum of process_counts across all
possible CPUs has meaning.
The only caller of nr_processes() is proc_root_getattr() which
calculates the number of links to /proc as
stat->nlink = proc_root.nlink + nr_processes();
You don't have to be all that unlucky for the nr_processes() to return a
negative value leading to a negative number of links (or rather, an
apparently enormous number of links). If this happens then you can get
failures where things like "ls /proc" start to fail because they got an
-EOVERFLOW from some stat() call.
Example with some debugging inserted to show what goes on:
# ps haux|wc -l
nr_processes: CPU0: 90
nr_processes: CPU1: 1030
nr_processes: CPU2: -900
nr_processes: CPU3: -136
nr_processes: TOTAL: 84
proc_root_getattr. nlink 12 + nr_processes() 84 = 96
84
# echo 0 >/sys/devices/system/cpu/cpu1/online
# ps haux|wc -l
nr_processes: CPU0: 85
nr_processes: CPU2: -901
nr_processes: CPU3: -137
nr_processes: TOTAL: -953
proc_root_getattr. nlink 12 + nr_processes() -953 = -941
75
# stat /proc/
nr_processes: CPU0: 84
nr_processes: CPU2: -901
nr_processes: CPU3: -137
nr_processes: TOTAL: -954
proc_root_getattr. nlink 12 + nr_processes() -954 = -942
File: `/proc/'
Size: 0 Blocks: 0 IO Block: 1024 directory
Device: 3h/3d Inode: 1 Links: 4294966354
Access: (0555/dr-xr-xr-x) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2009-11-03 09:06:55.000000000 +0000
Modify: 2009-11-03 09:06:55.000000000 +0000
Change: 2009-11-03 09:06:55.000000000 +0000
I'm not 100% convinced that the per_cpu regions remain valid for offline
CPUs, although my testing suggests that they do. If not then I think the
correct solution would be to aggregate the process_count for a given CPU
into a global base value in cpu_down().
This bug appears to pre-date the transition to git and it looks like it
may even have been present in linux-2.6.0-test7-bk3 since it looks like
the code Rusty patched in http://lwn.net/Articles/64773/ was already
wrong.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
