[U-Boot] soft i2c behaviour on address not <ACK>ed

[U-Boot] soft i2c behaviour on address not <ACK>ed

[Eibach, Dirk]

While debugging an I2C problem I found in soft_i2c_read() and
soft_i2c_write():

if(write_byte(addr >> shift)) {
	PRINTD("i2c_read, address not <ACK>ed\n");
	return(1);
}

and

if(write_byte(addr >> shift)) {
	PRINTD("i2c_write, address not <ACK>ed\n");
	return(1);
}

This means that these functions are left without sending a STOP
condition to the bus and with SCL held low. Is that really intended?

Cheers
Dirk
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[U-Boot] soft i2c behaviour on address not <ACK>ed

[Heiko Schocher]

Hello Dirk,

Am 21.11.2013 13:34, schrieb Eibach, Dirk:
> While debugging an I2C problem I found in soft_i2c_read() and
> soft_i2c_write():
>
> if(write_byte(addr>>  shift)) {
> 	PRINTD("i2c_read, address not<ACK>ed\n");
> 	return(1);
> }
>
> and
>
> if(write_byte(addr>>  shift)) {
> 	PRINTD("i2c_write, address not<ACK>ed\n");
> 	return(1);
> }
>
> This means that these functions are left without sending a STOP
> condition to the bus and with SCL held low. Is that really intended?

This seems a bug to me ... could you send a patch?

bye,
Heiko
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