baf46b4e37
Fix scll/sclh calculations for HS and fast modes. Currently the driver uses equal (roughly) low/high times which will result in too short low time. OMAP3430 TRM gives the following equations: F/S: tLow = (scll + 7) * internal_clk tHigh = (sclh + 5) * internal_clk HS: tLow = (scll + 7) * fclk tHigh = (sclh + 5) * fclk Furthermore, the I2C specification sets the following minimum values for HS tLow/tHigh for capacitive bus loads 100 pF (maximum speed 3400) and 400 pF (maximum speed 1700): speed tLow tHigh 3400 160 ns 60 ns 1700 320 ns 120 ns and for F/S: speed tLow tHigh 400 1300 ns 600 ns 100 4700 ns 4000 ns By using duty cycles 33/66 (HS, F) and 50/50 (S) we stay above these minimum values. Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com> Acked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org> |
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| .. | ||
| algos | ||
| busses | ||
| chips | ||
| Kconfig | ||
| Makefile | ||
| i2c-boardinfo.c | ||
| i2c-core.c | ||
| i2c-core.h | ||
| i2c-dev.c | ||