I2C Problem on OMAP-L138 LogicPD EVM and PSP Driver impact

TommyG

This post: https://e2e.ti.com/support/embedded/f/354/p/68559/248084.aspx#248084 indicates that there is an issue with the LogicPD EVM implementation which results in PSP driver not using I2C HW peripheral, but rather uses GPIO bit banging solution.

I'd like to understand what the hardware issue is in detail and what is the recommended implementation to eliminate the HW problem so I2C HW peripheral could be used by the driver. Also, will the PSP driver be updated to use the I2C HW peripheral so systems that don't have the EVM problem can use more efficient driver implementation. If backward compatibility must be maintained could software switch be used to configure for bit banging or I2C controller?

Thanks.

over 14 years ago

0 jc-ti over 14 years ago

TI__Mastermind 27585 points

Hi Tommy, I've asked Logic what the issue was and if it has been corrected. We should head back from them soon.

From the description as long as you are not operating the core at 1.0V you would not have the issue and could use the I2C HW peripheral. However since the PSP has to support all operating points I don't believe they plan on offering two separate drivers unless the hardware issue can be resolved.

Jeff

0 jc-ti over 14 years ago

TI__Mastermind 27585 points

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

Errata E0019 describes the issue in detail: http://support.logicpd.com/downloads/1321/1015618_OMAP-L138_SOM-M1_Errata_093010.pdf

PCN 450, item 3.2.13 shows the fix, which was to remove U24: http://support.logicpd.com/downloads/1289/1014931C_OMAP-L138_SOM-M1_PCN.pdf

So the latest SOMs do not have the I2C issue and can use the hardware controller instead.

Jeff

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I2C Problem on OMAP-L138 LogicPD EVM and PSP Driver impact