Messages in this thread | | | From | Punnaiah Choudary Kalluri <> | Subject | RE: [RFC PATCH 1/2] spi: Add support for Zynq QSPI controller | Date | Thu, 10 Jul 2014 09:44:44 +0000 |
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HI Greet,
>-----Original Message----- >From: Harini Katakam [mailto:harinikatakamlinux@gmail.com] >Sent: Thursday, July 10, 2014 3:01 PM >To: Geert Uytterhoeven >Cc: Mark Brown; Grant Likely; Rob Herring; Pawel Moll; Mark Rutland; Ian >Campbell; Kumar Gala; linux-spi; linux-kernel@vger.kernel.org; >devicetree@vger.kernel.org; linux-doc@vger.kernel.org; David Woodhouse; >Brian Norris; Marek Vašut; Artem Bityutskiy; Geert Uytterhoeven; Sascha >Hauer; Jingoo Han; Sourav Poddar; Michal Simek; Punnaiah Choudary Kalluri >Subject: Re: [RFC PATCH 1/2] spi: Add support for Zynq QSPI controller > >Hi Geert, > >On Thu, Jul 10, 2014 at 2:48 PM, Geert Uytterhoeven ><geert@linux-m68k.org> wrote: >> Hi Harini, >> >> On Thu, Jul 10, 2014 at 10:50 AM, Harini Katakam <harinik@xilinx.com> >wrote: >>> + master->flags = SPI_MASTER_QUAD_MODE; >> >> SPI_MASTER_QUAD_MODE is not one of the SPI_MASTER_* defines >> in include/linux/spi/spi.h? >> > >I'm sorry about that. That flag is unused - will remove this statement. > >>> + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | >SPI_RX_QUAD | >>> + SPI_TX_DUAL | SPI_TX_QUAD; >> >> Your driver advertises Dual/Quad SPI Transfer capabilities, but it doesn't >> check spi_transfer.[tr]x_nbits? How can it determine when to enable >Dual/Quad? >> > >Here the driver is just giving information that the controller support it. >The MTD layer enables dual/quad based on what the flash supports; quad >being the first priority >I understand that the spi core reads rx, tx-bus-width property and >master support flags and >performs the necessary checks.
Just to add, the zynq qspi controller will automatically select the IO lines based On the flash command.
Regards, Punnaiah
> >Regards, >Harini
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