Commit Graph

9 Commits

Author SHA1 Message Date
Masahiro Yamada
fcbd4bddb3 i2c: uniphier-f: fix misdetection of incomplete STOP condition
Currently, the status register FI2C_SR is checked immediately after
a STOP condition is issued in case of the deferred STOP condition.
It takes typically 5-10 usec until the corresponding bits in the
register are set, so the error check for "stop condition was not
completed" is very likely to be false positive.

Add wait code to relax the status register check.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-24 11:19:15 +02:00
Masahiro Yamada
0b1c7716fd i2c: uniphier-f: set the adapter to master mode when probing
Currently, the adapter is set to the master mode at the first use.
Since then, it is kept in the slave mode, so unexpected glitch
signals on the I2C lines may cause the adapter into insane state.
Setting it to the master mode along with initialization solves the
problem.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reported-by: Akio Noda <noda.akio@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 22:41:31 +02:00
Masahiro Yamada
405188e86a i2c: uniphier-f: avoid WARN_ON() of clk_disable() in failure path
If clk_prepare_enable() fails, clk_disable_unprepare() is called in
the failure path, where the enable_count is still zero, so it hits
WARN_ON(core->enable_count == 0) in the clk_core_disable().

To fix this, make the clock setting more linear in the probe function
so that it can exploit "goto err" in case of error.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 22:41:02 +02:00
Wolfram Sang
56025e7bc2 i2c: uniphier{-f}: don't print error when adding adapter fails
The core will do this for us now.

Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-22 08:19:56 +02:00
Masahiro Yamada
8a35018301 i2c: uniphier: add "\n" at the end of error log
Just in case.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-27 19:09:04 +02:00
Masahiro Yamada
bca71ba034 i2c: uniphier: fix typos in error messages
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-02-12 20:23:37 +01:00
Masahiro Yamada
51549c087f i2c: uniphier_f: error out if bus speed is zero
There is code to divide by "bus_speed" some lines below.
To eliminate the possibility of division by zero, bail out if
"clock-frequency" is specified as zero.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-14 10:59:46 +01:00
Masahiro Yamada
ac9b91f39d i2c: uniphier_f: error out if clock rate is zero
This input clock is used to generate the sampling clock for I2C bus.
If the clock rate is zero, there is something wrong with the clock
driver.  Bail out with the appropriate error message in such a case.
It would make it easier to find the root cause of failure.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-14 10:59:26 +01:00
Masahiro Yamada
6a62974b66 i2c: uniphier_f: add UniPhier FIFO-builtin I2C driver
Add support for on-chip I2C controller used on newer UniPhier SoCs
such as PH1-Pro4, PH1-Pro5, etc.  This adapter is equipped with
8-depth TX/RX FIFOs.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-23 21:55:46 +02:00