2009-09-11 10:29:00     Slave Clock Stretch detection with I2C-GPIO driver.

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2009-09-11 10:29:00     Slave Clock Stretch detection with I2C-GPIO driver.

zigma dsp (GERMANY)

Message: 79806   

 

Slave I2C devices can stretch the clock, by pulling the clock line low. Will the I2C device driver using GPIO (for BF533/BF561, and when DSP is the Master) support this case?

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2009-09-11 11:52:18     Re: Slave Clock Stretch detection with I2C-GPIO driver.

Mike Frysinger (UNITED STATES)

Message: 79809   

 

the bit banging I2C driver is not specific to any Blackfin device.  it'll work the same regardless of the processor you're using.

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2009-09-11 12:01:25     Re: Slave Clock Stretch detection with I2C-GPIO driver.

zigma dsp (GERMANY)

Message: 79811   

 

So, it does support the Stretching of Clock by a Slave device?

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2009-09-11 12:11:24     Re: Slave Clock Stretch detection with I2C-GPIO driver.

Robin Getz (UNITED STATES)

Message: 79812   

 

Zigma:

 

Look at the source. drivers/i2c/busses/i2c-gpio.c

 

        dev_info(&pdev->dev, "using pins %u (SDA) and %u (SCL%s)\n",

                 pdata->sda_pin, pdata->scl_pin,

                 pdata->scl_is_output_only

                 ? ", no clock stretching" : "");

 

 

So, it depends on your GPIO, and platform data.

 

-Robin

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