Commit Graph

151 Commits

Author SHA1 Message Date
Sonic Zhang
07612e5f22 spi: spi_bfin: resequence DMA start/stop
Set correct baud for spi mmc and enable SPI only after DMA is started.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.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>
2007-12-05 09:21:20 -08:00
Bryan Wu
62310e51ac spi: spi_bfin: update handling of delay-after-deselect
Move cs_chg_udelay handling (specific to this driver) to cs_deactive(), fixing
a bug when some SPI LCD driver needs delay after cs_deactive.

Fix bug reported by Cameron Barfield <cbarfield@cyberdata.net>
https://blackfin.uclinux.org/gf/project/uclinux-dist/forum/?action=ForumBrowse&forum_id=39&_forum_action=ForumMessageBrowse&thread_id=23630&feedback=Message%20replied.

Cc: Cameron Barfield <cbarfield@cyberdata.net>
Signed-off-by: Bryan Wu <bryan.wu@analog.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>
2007-12-05 09:21:20 -08:00
Bryan Wu
c3061abb9e spi: spi_bfin: bugfix for 8..16 bit word sizes
Fix bug in u16_cs_chg_reader to read data_len-2 bytes data firstly, then read
out the last 2 bytes data

Signed-off-by: Bryan Wu <bryan.wu@analog.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>
2007-12-05 09:21:20 -08:00
Bryan Wu
bb90eb00b6 spi: spi_bfin: handle multiple spi_masters
Move global SPI regs_base and dma_ch to struct driver_data.  Test on BF54x SPI
Flash with 2 spi_master devices enabled.

Signed-off-by: Bryan Wu <bryan.wu@analog.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>
2007-12-05 09:21:19 -08:00
Sonic Zhang
3f479a65b3 spi: spi_bfin: relocate spin/waits
Move spin/waits to more correct locations in bfin SPI driver.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.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>
2007-12-05 09:21:19 -08:00
Sonic Zhang
cc487e7320 spi: spi_bfin: change handling of communication parameters
Fix SPI driver to work with SPI flash ST M25P16 on bf548

Currently the SPI driver enables the SPI controller and sets the SPI baud
register for each SPI transfer.  But they should never be changed within a SPI
message session, in which several SPI transfers are pumped.

This patch moves SPI setting to the begining of a message session, and
never disables SPI controller until an error occurs.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.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>
2007-12-05 09:21:19 -08:00
Sonic Zhang
12e17c4267 spi: spi_bfin, rearrange portmux calls
Move pin muxing to setup and cleanup methods.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.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>
2007-12-05 09:21:19 -08:00
Sonic Zhang
7c4ef09449 spi: spi_bfin uses portmux for additional busses
Use portmux mechanism to support SPI busses 1 and 2, instead of just the
original bus 0.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.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>
2007-12-05 09:21:19 -08:00
Bryan Wu
a32c691d7c spi: spi_bfin uses platform device resources
Update spi driver to support multi-ports by using platform resources; tested
on STAMP537+SPI_MMC, other boards need more testing.  Plus other minor
updates.

Signed-off-by: Bryan Wu <bryan.wu@analog.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>
2007-12-05 09:21:19 -08:00
Mike Frysinger
2ed355165f spi: spi_bfin, don't bypass spi framework
Prevent people from setting bits in ctl_reg that the SPI framework already
handles, hopefully we can one day drop ctl_reg completely

Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.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>
2007-12-05 09:21:19 -08:00
Bryan Wu
fad91c8909 spi: spi_bfin handles spi_transfer.cs_change
Respect per-transfer cs_change field (protocol tweaking support) by
adding and using cs_active/cs_deactive functions.

Signed-off-by: Bryan Wu <bryan.wu@analog.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>
2007-12-05 09:21:19 -08:00
Bryan Wu
5fec5b5a4e spi: spi_bfin cleanups, error handling
Cleanup and error handling

 - add error handling in SPI bus driver with selecting clients
 - use proper defines to access Blackfin MMRs
 - remove useless SSYNCs
 - cleaner use of portmux calls

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.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>
2007-12-05 09:21:19 -08:00
Michael Hennerich
cc2f81a695 spi: bfin spi uses portmux calls
Use new Blackfin portmux interface, add error handling.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.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>
2007-12-05 09:21:19 -08:00
Bryan Wu
131b17d42d spi: initial BF54x SPI support
Initial BF54x SPI support

 - support BF54x SPI0
 - clean up some code (whitespace etc)
 - will support multiports in the future
 - start using portmux calls

Signed-off-by: Bryan Wu <bryan.wu@analog.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>
2007-12-05 09:21:19 -08:00
Marc Pignat
9b938b7490 spi: simplify spi_sync() calling convention
Simplify spi_sync calling convention, eliminating the need to check both
the return value AND the message->status.  In consequence, this corrects
misbehaviours of spi_read and spi_write (which only checked the former) and
their callers.

Signed-off-by: Marc Pignat <marc.pignat@hevs.ch>
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>
2007-12-05 09:21:18 -08:00
David Brownell
3f86f14c0f spi: at25 driver is for EEPROM not FLASH
Add comment to at25 driver that it's for EEPROM chips, not FLASH
chips ... the AT25 series has both types of chip, and sometimes
they're even pin-compatible.  The command sets are different, as
is the treatment of erasure.  (FLASH needs explicit erasure, but
with EEPROM it's implicit.)  Note that all vendors seem to have
this same confusion in their *25* series SPI memory parts.

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>
2007-12-05 09:21:18 -08:00
David Brownell
068f407086 SPI: use mutex not semaphore
Make spi_write_then_read() use a mutex not a binary semaphore.

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>
2007-12-05 09:21:18 -08:00
David Brownell
75d427982f spi: S3C2410: add bus number to SPI GPIO driver
Allow passing a bus number through the platform data for the S3C2410 SPI
GPIO driver.   This is needed to support multiple SPI busses.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
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>
2007-11-29 09:24:52 -08:00
Ben Dooks
438ae1ae7b S3C24XX: ensure we only configure valid GPIOs
If we specify an GPIO which cannot be used for the purpose, then assume
that the GPIO is not to be used and do not try and configure it.  This can
be the case where the SPI bus is TX only.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
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>
2007-11-29 09:24:52 -08:00
David Brownell
65f97a5694 atmel_spi: label GPIOs better
Make the atmel_spi driver label GPIOs according to the device for which
they're acting as a chipselect.  This way the debugfs dump of gpio state is
more informative.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-29 09:24:51 -08:00
Mike Frysinger
529a73fbae Blackfin arch: punt CONFIG_BFIN -- we already have CONFIG_BLACKFIN
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-23 14:28:44 +08:00
David Brownell
822bd5aa2b tle62x0 driver stops ignoring read errors
The tle62x0 driver was ignoring all read errors.  This patch makes it
pass such errors up the stack, instead of returning bogus data.

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>
2007-11-14 18:45:42 -08:00
Atsushi Nemoto
ba0a7f39ce spi: fix error paths on txx9spi_probe
Some error paths in txx9spi_probe wrongly return 0.  This patch fixes them by
using the devres interfaces.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Acked-by: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-14 18:45:39 -08:00
Atsushi Nemoto
350d0076c5 spi: fix double-free on spi_unregister_master
After 49dce689ad, device_for_each_child
iteration hits the master device itself.  Do not call spi_unregister_device()
for the master device.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Acked-by: David Brownell <david-b@pacbell.net>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-14 18:45:39 -08:00
Al Viro
142956af52 fix abuses of ptrdiff_t
Use of ptrdiff_t in places like

-                       if (!access_ok(VERIFY_WRITE, u_tmp->rx_buf, u_tmp->len))
+                       if (!access_ok(VERIFY_WRITE, (u8 __user *)
+                                               (ptrdiff_t) u_tmp->rx_buf,
+                                               u_tmp->len))

is wrong; for one thing, it's a bad C (it's what uintptr_t is for; in general
we are not even promised that ptrdiff_t is large enough to hold a pointer,
just enough to hold a difference between two pointers within the same object).
For another, it confuses the fsck out of sparse.

Use unsigned long or uintptr_t instead.  There are several places misusing
ptrdiff_t; fixed.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-29 07:41:33 -07:00
Robert P. J. Day
3a4fa0a25d Fix misspellings of "system", "controller", "interrupt" and "necessary".
Fix the various misspellings of "system", controller", "interrupt" and
"[un]necessary".

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-19 23:10:43 +02:00
Joe Perches
898eb71cb1 Add missing newlines to some uses of dev_<level> messages
Found these while looking at printk uses.

Add missing newlines to dev_<level> uses
Add missing KERN_<level> prefixes to multiline dev_<level>s
Fixed a wierd->weird spelling typo
Added a newline to a printk

Signed-off-by: Joe Perches <joe@perches.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Mark M. Hoffman <mhoffman@lightlink.com>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Tilman Schmidt <tilman@imap.cc>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Stephen Hemminger <shemminger@linux-foundation.org>
Cc: Greg KH <greg@kroah.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Cc: James Smart <James.Smart@Emulex.Com>
Cc: Andrew Vasquez <andrew.vasquez@qlogic.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Jaroslav Kysela <perex@suse.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 14:37:28 -07:00
Tony Jones
49dce689ad spi doesn't need class_device
Make the SPI framework and drivers stop using class_device.  Update docs
accordingly ...  highlighting just which sysfs paths should be
"safe"/stable.

Signed-off-by: Tony Jones <tonyj@suse.de>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:10 -07:00
Anton Vorontsov
328329a7bd spi_mpc83xx handles other processors with QUICC engine
Currently, all QE SPI controllers are almost the same comparing to
MPC83xx's, thus let's use that driver for them.

Tested to work on MPC85xx in loopback mode.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
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>
2007-10-16 09:43:10 -07:00
David Brownell
d1e44d9ce8 SPI driver runtime footprint shrinkage
Shrink the runtime footprint of various SPI drivers:

  - Move the probe() routine into the init section where practical,
    using platform_driver_probe() to make that safe.  This often saves
    around 1KB.  Using platform_driver_probe() can also be a correctness
    fix, if the probe routine is already marked __init but the driver
    struct keeps a dangling pointer to it after init section removal.

  - Likewise move remove() routines into the exit sections.

These changes would be inappropriate iff the platform devices were
actually hotpluggable (e.g. they're found on optional addon cards,
or in an FPGA that's dynamically reprogrammed).  In these cases,
that's not the situation; it's an SOC controller and the only device
is initialized before these drivers.

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>
2007-10-16 09:43:09 -07:00
Kyungmin Park
86eeb6fe71 OMAP2 McSPI code cleanup
Remove unused variable & write space

Signed-off-by: Kyungmin Park <kyungmin.park@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>
2007-10-16 09:43:09 -07:00
Jesper Juhl
8b7f9b81c8 Clean up duplicate includes in drivers/spi/
This patch cleans up duplicate includes in
	drivers/spi/

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Acked-by: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:09 -07:00
Kay Sievers
7eff2e7a8b Driver core: change add_uevent_var to use a struct
This changes the uevent buffer functions to use a struct instead of a
long list of parameters. It does no longer require the caller to do the
proper buffer termination and size accounting, which is currently wrong
in some places. It fixes a known bug where parts of the uevent
environment are overwritten because of wrong index calculations.

Many thanks to Mathieu Desnoyers for finding bugs and improving the
error handling.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12 14:51:01 -07:00
Jan Andersson
65e213cdb2 spi_mpc83xx: hang fix
When the spi_mpc83xx driver receives a tx_buf pointer which is NULL, it
only writes one zero filled word to the transmit register.  If the driver
expects to receive more than one word it will wait forever for a second
receive interrupt.  With this patch the controller will shift out zeroes
until all words have been received.

Signed-off-by: Jan Andersson <jan@gaisler.com>
Tested-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-09-11 17:21:19 -07:00
Andrew Victor
85787a2bea Fix typo in atmel_spi.c
Fix cut 'n paste bug in Atmel SPI driver.

Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Acked-by: David Brownell <david-b@pacbell.net>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-31 01:42:23 -07:00
Atsushi Nemoto
4ccdb4c872 spi: correct name for spi_txx9
Correct the name of the spi_txx9 driver (and their in-tree user)
instead of MODULE_ALIAS workaround.  This would be preferable in the
long term.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Acked-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>
2007-08-31 01:42:22 -07:00
David Brownell
fc3ba9525b SPI driver hotplug/coldplug fixes
Update various SPI drivers so they properly support

  - coldplug through "modprobe $(cat /sys/devices/.../modalias)"

  - hotplug through "modprobe $(MODALIAS)"

The basic rule for platform, SPI, and (new style) I2C drivers is just
to make sure that modprobing the driver name works.  In this case, all
the relevant drivers are platform drivers, and this patch either

  (a)	Changes the driver name, if no in-tree code would break;
	this is simpler and thus preferable in the long term.

  (b)	Adds MODULE_ALIAS directives, when in-tree platforms declare
	devices using the current driver name; less desirable.

Most systems will link SPI controller drivers statically, but
there's no point in being needlessly broken.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Jean Delvare <khali@linux-fr.org>
Acked-by: Andrei Konovalov <akonovalov@ru.mvista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-31 01:42:22 -07:00
David Brownell
96ddbf504a spidev warning fix
Git rid of "warning: passing arg 2 of `access_ok' makes pointer from integer
without a cast" reported on SH ...  most architectures use macros in that
test, SH uses inlined functions.

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>
2007-08-11 15:47:42 -07:00
Anton Vorontsov
a44648b057 spi_mpc83xx: fix prescale modulus calculation
Long ago I've noticed (but didn't pay much attention) that
spi_mpc83xx using PM calculations that differs from what
specs describe. I.e.

u8 pm = mpc83xx_spi->spibrg / (spi->max_speed_hz * 4);

While specs says: "The SPI baud rate generator clock source (either
system clock or system clock divided by 16, depending on DIV16 bit) is
divided by 4 * ([PM] + 1), a range from 4 to 64.".

Thus " - 1" is missing in the spi_mpc83xx's formula.

Why nobody noticed that bug? Probably because sysclk usually less then
user expects, e.g. you expect 200 MHz, but real clock is 198 MHz,
and integer rounding helps when this formula is used.

Suppose it's SPI in QE, SYSCLK at 198 MHz, thus SPIBRG at 99MHz, 25 MHz
requested.

PM = (99MHz / ( 25 MHz * 4 )), PM == 0, output SPICLK will be 24.75 MHz

At lower frequencies this bug is more noticeable, though.

And this bug shows itself in all its beauty if SYSCLK is equal or a bit
more than you expect (200 MHz SYSCLK, 100 MHz SPIBRG):
PM = (100MHz / ( 25 MHz * 4 )), PM == 1, output SPICLK will be 12.625 MHz!

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.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>
2007-08-11 15:47:41 -07:00
Anton Vorontsov
e24a4d1ee3 spi_mpc83xx: in "QE mode", use sysclk/2
For MPC8349E input to the SPI Baud Rate Generator is SYSCLK, but it's
SYSCLK/2 for MPC8323E (SPI in QE).  Fix this, and remove confusion by
renaming the mpc83xx_spi->sysclk member as mpc83xx_spi->spibrg.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.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>
2007-08-11 15:47:41 -07:00
David Brownell
082c8cb4e5 spi device setup gets better error checking
This updates some error reporting paths in SPI device setup:

 - Move validation logic for SPI chipselects to spi_new_device(),
   which is where it should always have been.

 - In spi_new_device(), emit error messages if the device can't
   be created.  This is LOTS better than a silent failure; though
   eventually, the calling convention should probably change to
   use the <linux/err.h> conventions.

 - Includes one previously-missing check:  SPI masters must always
   have at least one chipselect, even for dedicated busses which
   always keep it selected!

It also adds a FIXME (IDR for dynamic ID allocation) so the issue doesn't live
purely in my mailbox.

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>
2007-07-31 15:39:44 -07:00
Anton Vorontsov
2a485d7ad2 spi_mpc83xx: support loopback mode
This exposes the hardware loopback mode to drivers, primarily for testing.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.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>
2007-07-31 15:39:40 -07:00
Anton Vorontsov
6f166e3833 spidev supports more communications modes
The spidev driver doesn't currently expose all SPI communications modes to
userspace.  This passes them all through to the driver.

Two of them are potentially troublesome, in the sense that they could cause
hardware conflicts on shared busses.  It might be appropriate to add some
privilege checks for for those modes.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.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>
2007-07-31 15:39:40 -07:00
Anton Vorontsov
35cc0b9750 spi_mpc83xx: fix QE+LSB mode shifts
spi_mpc83xx should use other shifts when running in QE+LSB mode.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
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>
2007-07-31 15:39:40 -07:00
Anton Vorontsov
32421daaf8 spi_mpc83xx: support for lsb-first transfers
This controller supports LSB-first transfers; let drivers use them.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
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>
2007-07-31 15:39:39 -07:00
Anton Vorontsov
20ba09b979 spi_mpc83xx: get rid of magic numbers
Magic-numbers-R-Evil

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
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>
2007-07-31 15:39:39 -07:00
Anton Vorontsov
49bb23006b spi_mpc83xx: turn off SPI unit while switching mode
Documentation clearly states, that mode should not be changed till
SPMODE_ENABLE bit set.  I've seen hangs w/o this patch.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
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>
2007-07-31 15:39:39 -07:00
Ben Dooks
47572b84aa fixup s3c24xx build after arch moves
Fix the include files moved around during the s3c24xx arch moves.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
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>
2007-07-26 11:35:16 -07:00
Adrian Bunk
149a6501f9 spi.c:scan_boardinfo() mustn't be __init_or_module
WARNING: drivers/built-in.o(.text+0x889735): Section mismatch: reference to .init.text:scan_boardinfo (between 'spi_register_master' and '__unregister')

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-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>
2007-07-21 17:49:16 -07:00
Matthias Kaehlcke
9404082898 use mutex instead of semaphore in SPI core/init code
The SPI core/init code uses a semaphore as mutex.  Use the mutex API instead
of the (binary) semaphore.

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Acked-by: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17 10:23:05 -07:00