Messages in this thread |  | | Date | Wed, 12 Nov 2014 23:06:24 +0000 | From | Mark Brown <> | Subject | Re: [PATCH 2/2] spi: Add driver for IMG SPFI controller |
| |
On Wed, Nov 12, 2014 at 02:54:57PM -0800, Andrew Bresticker wrote: > On Wed, Nov 12, 2014 at 2:07 PM, Mark Brown <broonie@kernel.org> wrote:
> >> drivers/spi/spi-img.c | 703 ++++++++++++++++++++++++++++++++++++++++++++++++++
> > How about spi-img-spfi? That way if someone makes another SPI > > controller (say a more generic one, this one seems flash specialized) > > there won't be a collision.
> Despite the name, I believe this controller is used for generic SPI > stuff as well. I'm not sure if there is a separate one which is more > generic (James?).
It would still be better to use a name less impressively generic - this is an entire company, not even a product line.
> >> + cpu_relax();
> > Seems random - we already relax in the data transfer?
> We don't relax in the transfers - would that be a better place to put > it? I thought it was better here since we reach this point once the > TX FIFO has filled or RX FIFO has emptied.
Oh, that was the FIFO drain I was thinking of. I guess here is fine.
> >> + if (tx_buf) > >> + spfi_flush_tx_fifo(spfi); > >> + spfi_disable(spfi);
> > What does the enable and disable actually do? Should this be runtime > > PM?
> It starts/stops the transfer. The control registers (bit clock, > transfer mode, etc.) must be programmed before the enable bit is set > and the bit does not clear itself upon completion of the transfer. I > don't think it makes sense to have this be part of runtime PM.
Perhaps these functions need to be called start() and stop() then - the names sound like they gate the IP?
> > This will unconditionally claim to have handled an interrupt even if it > > didn't get any interrupt status it has ever heard of. At the very least > > it should log unknown interrupts, ideally return IRQ_NONE though since > > it seems to be a clear on read interrupt that's a bit misleading.
> There's a clear register actually (see the writel() above), but yes, > an error and returning IRQ_NONE sound appropriate in the event of an > unexpected interrupt.
Don't add the error print - the interrupt core has diagnostics already and it won't be nice if the interrupt ends up shared. My recommendation was intended as an either/or. [unhandled content-type:application/pgp-signature] |  |