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path: root/drivers/i2c/algos/i2c-algo-bit.c
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* i2c-algo-bit: Improve debuggingJean Delvare2007-05-01
| | | | | | | | | | | | | | 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>
* i2c-algo-bit: Implement a 50/50 SCL duty cycleJean Delvare2007-05-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* i2c-algo-bit: Add i2c_bit_add_numbered_busJean Delvare2007-05-01
| | | | | | | | 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>
* i2c-algo-bit: Emulate SMBus block readJean Delvare2007-05-01
| | | | | | | | | 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>
* i2c-algo-bit: Always send a stop condition before leavingJean Delvare2007-05-01
| | | | | | | | | | 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>
* i2c: Discard the i2c algo del_bus wrappersJean Delvare2006-12-10
| | | | | | | They are all only calling i2c_del_adapter, so we may as well do it directly. Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c: Constify i2c_algorithm declarations, part 1Jean Delvare2006-09-26
| | | | | | | | | | | | 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: CleanupsJean Delvare2006-09-26
| | | | | | | | | | | | 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 memberJean Delvare2006-09-26
| | | | | | | | | | | | | | 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>
* [PATCH] i2c-algo-bit: Wipe out dead codeUwe Bugla2006-07-12
| | | | | | | | i2c-algo-bit: Wipe out dead code Signed-off-by: Uwe Bugla <uwe.bugla@gmx.de> Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] i2c: Handle i2c_add_adapter failure in i2c algorithm driversMark M. Hoffman2006-07-12
| | | | | | | | | | | 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>
* [PATCH] I2C: Kill i2c_algorithm.id (5/7)Jean Delvare2005-09-05
| | | | | | | | | 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>
* [PATCH] I2C: Kill i2c_algorithm.id (4/7)Jean Delvare2005-09-05
| | | | | | | | 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>
* [PATCH] I2C: Kill i2c_algorithm.id (3/7)Jean Delvare2005-09-05
| | | | | | | | | 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>
* [PATCH] I2C: Kill i2c_algorithm.name (1/7)Jean Delvare2005-09-05
| | | | | | | | | 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>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-16
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!