Re: [RFC] spi: dw: support setting tmode dynamically

[Jisheng Zhang]

Dear Mark,

On Wed, 23 Dec 2015 12:15:12 +0000 Mark Brown wrote:

> On Wed, Dec 23, 2015 at 07:23:38PM +0800, Jisheng Zhang wrote:
> 
> > Currently the spi-dw tmode is fixed to SPI_TMOD_TR if cs_control is NULL, but we
> > need to set it as SPI_TMOD_EPROMREAD to read nor flash, my solution is to add and
> > export one functions to set the tmode, then the nor flash driver call it
> > before reading and set back to SPI_TMOD_TR after done.  
> 
> What does this mean - what is TMOD and why do we need to set it to read
> NOR flash?  I've no information on this controller...

TMOD is one field of DW_SPI_CTRL0. Its available value could be:

0: Transmit and Receive

1: Transmit only

2: Receive only

3: EEPROM Read

If the one spi nor flash is connected to the SPI host, so far I can only succeed
to read the nor flash content after setting the TMOD field as 3.

Thanks,
Jisheng
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/