i2c: Constify i2c_algorithm declarations, part 2

Make struct i2c_algorithm declarations const in all i2c bus drivers
where it is possible.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

While busy-waiting for completion, check the hardware after scheduling;
don't schedule and then immediately check the _timeout_.  If the yield()
took a long time (as it does on my OLPC prototype board when it's busy),
we'd report a timeout even though the hardware was now ready.

This fixes it, and also switches the yield() for a cond_resched() because
we don't actually want to be _that_ nice about it.  I see nice
tightly-packed SMBus transactions now, rather than waiting for milliseconds
between successive phases.

Actually, we shouldn't be busy-waiting here at all.  We should be using
interrupts.  That's an exercise for another day though.
Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>
Cc: Christer Weinigel <wingel@nano-system.com>
Cc: <Jordan.Crouse@amd.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The scx200_acb i2c bus driver pretends to support SMBus block
transactions, but in fact it implements the more simple I2C block
transactions. Additionally, it lacks sanity checks on the length
of the block transactions, which could lead to a buffer overrun.

This fixes an oops reported by Alexander Atanasov:
http://marc.theaimsgroup.com/?l=linux-kernel&m=114970382125094

Thanks to Ben Gardner for fixing my bugs :)
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Fix the scx200_acb state machine:

* Nack was sent one byte too late on reads >= 2 bytes.
* Stop bit was set one byte too late on reads.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

In i2c bus driver scx200_acb, function scx200_acb_probe can be
tagged __init.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

On the CS5535 and CS5536, the I/O resource is allocated through PCI,
so use that instead of using the MSR backdoor.
Signed-off-by: NJordan Crouse <jordan.crouse@amd.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

WARNING: drivers/i2c/busses/scx200_acb.o - Section mismatch: reference to
.init.text: from .text after 'scx200_add_cs553x' (at offset 0x528)
Signed-off-by: NRandy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This is a fix for the CS5535 errata 111:

When the SMBus controller tries to access a non-existing device, it sets
the NEGACK bit, SMBus I/O offset 01h[4], to 1 after it detects no
acknowledge at the ninth clock.  The specification states that the bit
can be cleared by writing a 1 to it, but under certain circumstances it
is possible for this bit to not clear.

Writing a 0 to the bit resets the internal state machine and clears the
issue.

Since all writable bits in ACBST are W1C bits (write-one-to-clear) the
second write doesn't affect any other logic except the buggy NEGACK
state machine. The second write clears an internal register which is
responsible for "overwriting" the NEGACK bit in ACBST.
Signed-off-by: NJordan Crouse <jordan.crouse@amd.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

We can't pass a string on the stack to request_region. As soon as we
leave the function that stack is gone and the string is lost. Let's
use the same string we identify the i2c_adapter with instead, it's
more simple, more consistent, and just works.

This is the second half of fix to bug #6445.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The scx200_acb driver shouldn't return failure after initialization
if it successfully registered at least one i2c_adapter, else we are
leaking resources. The driver was OK in that respect up to 2.6.16, a
recent change broke it.

This is part of the fix to bug #6445.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Cc: Ben Gardner <bgardner@wabtec.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Cleanup after the semaphores to mutexes conversions in the i2c
subsystem.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

scx200_acb: Fix and speed up the poll loop
Signed-off-by: NBen Gardner <bgardner@wabtec.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

scx200_acb: Add support for the CS5535/CS5536
Signed-off-by: NBen Gardner <bgardner@wabtec.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

scx200_acb: remove use of lock_kernel()
Signed-off-by: NBen Gardner <bgardner@wabtec.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

scx200_acb: refactor/simplify code (no functional changes)
Signed-off-by: NBen Gardner <bgardner@wabtec.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

scx200_acb: debug log cleanup
Signed-off-by: NBen Gardner <bgardner@wabtec.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

scx200_acb: Whitespace and comment cleanup
Signed-off-by: NBen Gardner <bgardner@wabtec.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Use kzalloc instead of kmalloc+memset in all remaining i2c bus and
chip drivers.
Signed-off-by: NDeepak Saxena <dsaxena@plexity.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

In theory, there should be no more users of I2C_ALGO_* at this point.
However, it happens that several drivers were using I2C_ALGO_* for
adapter ids, so we need to correct these before we can get rid of all
the I2C_ALGO_* definitions.

Note that this also fixes a bug in media/video/tvaudio.c:

	/* don't attach on saa7146 based cards,
	   because dedicated drivers are used */
	if ((adap->id & I2C_ALGO_SAA7146))
		return 0;

This test was plain broken, as it would succeed for many more adapters
than just the saa7146: any those id would share at least one bit with
the saa7146 id. We are really lucky that the few other adapters we want
this driver to work with did not fulfill that condition.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

There are no more users of i2c_algorithm.id, so we can finally drop
this structure member.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The name member of the i2c_algorithm is never used, although all
drivers conscientiously fill it. We can drop it completely, this
structure doesn't need to have a name.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Files that don't use CONFIG_* stuff shouldn't include config.h
Files that use CONFIG_* stuff should include config.h

It's that simple. ;-)
Signed-off-by: NAlexey Dobriyan <adobriyan@mail.ru>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!