This fixes a bug in the way i2c-algo-bit handles I2C_M_RECV_LEN,
used to implement i2c_smbus_read_block_data(). Previously, in the
absence of PEC (rarely used!) it would NAK the "length" byte:
S addr Rd [A] [length] NA
That prevents the subsequent data bytes from being read:
S addr Rd [A] [length] { A [data] }* NA
The primary fix just reorders two code blocks, so the length used
in the "should I NAK now?" check incorporates the data which it
just read from the slave device.
However, that move also highlighted other fault handling glitches.
This fixes those by abstracting the RX path ack/nak logic, so it
can be used in more than one location. Also, a few CodingStyle
issues were also resolved.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This driver has been broken forever. It depends on i2c-algo-8xx which
has never been in the mainline kernel.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Allow the whole I2C menu to be disabled at once without diving into
the submenus for deselecting all options (should the user desire so).
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Improve the debugging features of the i2c-algo-bit driver:
* Make it possible to compile the driver without debugging support
at all, making it much smaller.
* Use dev_dbg() for debugging messages where possible, and dev_err()
for error messages.
* Remove redundant debugging messages.
These changes allowed for minor code cleanups, which are included
as well.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The original i2c-algo-bit implementation uses a 33/66 SCL duty cycle
when bits are being written on the bus. While the I2C specification
doesn't forbid it, this prevents us from driving the I2C bus to its
max speed, limiting us to 66 kbps max on standard I2C busses.
Implementing a 50/50 duty cycle instead lets us max out the bandwidth
up to the theoretical max of 100 kbps on standard I2C busses. This is
particularly important when large amounts of data need to be transfered
over the bus, as is the case with some TV adapters when the firmware is
being uploaded.
In fact this change even allows, at least in theory, fast-mode I2C
support at 125, 166 and 250 kbps. There's no way to reach the
theoretical max of 400 kbps with this implementation. But I don't
think we want to put efforts in that direction anyway: software-driven
I2C is very CPU-intensive and bad for latency.
Other timing changes:
* Don't set SDA high explicitly on error, we're going to issue a stop
condition before we leave anyway.
* If an error occurs when sending the slave address, yield the CPU
before retrying, and remove the additional delay after the new start
condition.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Add i2c_bit_add_numbered_bus(), which is equivalent to i2c_bit_add_bus
except that it calls i2c_add_numbered_adapter() at the end instead of
i2c_add_adapter().
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Now that i2c-core lets the i2c bus drivers emulate the SMBus block read
and SMBus block process call transaction types, let's implement that in
the popular i2c bit-banging driver. This will also act as a reference
implementation for other bus drivers which want to do the same.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The i2c-algo-bit driver doesn't behave well on read errors: it'll
bail out without even sending a stop condition on the bus, so the bus
will be stuck. So make sure that we always send a stop condition on
the bus before we leave. The best way to make sure is to always send
it at the end of function bit_xfer.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The rest of the ITE8172 support was already removed from MIPS tree.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
i2c: Constify i2c_algorithm declarations, part 1
Make struct i2c_algorithm declarations const in all i2c algorithm
drivers.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
i2c-algo-bit: Cleanups
* Uninline long functions (saves around 1 kB or 15%)
* Refactor code in sclhi()
* Drop redundant udelay on repeated start
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
i2c-algo-bit: Discard the mdelay data struct member
The i2c_algo_bit_data structure has an mdelay member, which is not
used by the algorithm code (the code has always been ifdef'd out.)
Let's discard it to save some code and memory.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Mauro Carvalho Chehab <mchehab@brturbo.com.br>
Cc: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
i2c-algo-sibyte: Merge into i2c-sibyte
Merge i2c-algo-sibyte into i2c-sibyte, as this is a complete,
hardware-dependent SMBus implementation and not a reusable algorithm.
Perform some basic coding style cleanups while we're here (mainly
space-based indentation replaced by tabulations.)
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Content-Disposition: inline; filename=i2c-algo-error-handling-fix.patch
It is possible for i2c_add_adapter() to fail. Several I2C algorithm
drivers ignore that fact. This (compile-tested only) patch fixes them.
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
this patch changes MODULE_PARM usage
to module_param in i2c-algo-sibyte.c
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The sgi_xfer function returns 0 on success instead of the number of
transfered messages as it is supposed to. This patch fixes that.
Let's just hope that no client chip driver was relying on this
misbehavior.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Merge the algorithm id part (16 upper bits) of the i2c adapters ids
into the definition of the adapters ids directly. After that, we don't
need to OR both ids together for each i2c_adapter structure.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg 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: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Don't rely on i2c_algorithm.id to alter the i2c adapter's id, use the
I2C_ALGO_* value directly instead, because i2c_algorithm will soon
have no id member no more.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg 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: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
I've been running with this patch for a while now, and while I've never
seen it trigger except with buggy hardware I think it is a cleaner way
to handle a busy bus. I had -EBUSY until about 10 minutes ago but -EIO
seems to be what most of the existing algo drivers will return in the
same circumstances.
Signed-off-by: Ian Campbell <icampbell@arcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Here is a simple patch originally from Denis Vlasenko, which strips a
useless trailing whitespace from 8 strings in 4 i2c drivers. Please
apply, thanks.
From: Denis Vlasenko <vda@ilport.com.ua>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch fixes the some misspellings and a trailing whitespace in
the comments.
Signed-off-by: Tobias Klauser <tklauser@nuerscht.ch>
Signed-off-by: Greg 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: Alexey Dobriyan <adobriyan@mail.ru>
Signed-off-by: Greg 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!
