Subject: [PATCH 1/4] spi: add support for octal I/O data transfer

From: [email-masked] (Boris Brezillon)
Date: Thu, 4 Oct 2018 11:04:46 +0200

Hi Yogesh,

On Thu,  4 Oct 2018 14:18:37 +0530
Yogesh Gaur <[email-masked]> wrote:

> Add flags for Octal I/O data transfer
> Required for the SPI controller which can do the data transfer (TX/RX)
> on 8 data lines e.g. NXP FlexSPI controller.
>  SPI_TX_OCTAL: transmit with 8 wires
>  SPI_RX_OCTAL: receive with 8 wires
> 
> Signed-off-by: Yogesh Gaur <[email-masked]>
> ---
>  drivers/spi/spi.c       | 6 ++++++
>  include/linux/spi/spi.h | 2 ++
>  2 files changed, 8 insertions(+)
> 
> diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
> index ec395a6..80f672f 100644
> --- a/drivers/spi/spi.c
> +++ b/drivers/spi/spi.c
> @@ -1573,6 +1573,9 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi,
>  		case 4:
>  			spi->mode |= SPI_TX_QUAD;
>  			break;
> +		case 8:
> +			spi->mode |= SPI_TX_OCTAL;
> +			break;
>  		default:
>  			dev_warn(&ctlr->dev,
>  				"spi-tx-bus-width %d not supported\n",
> @@ -1591,6 +1594,9 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi,
>  		case 4:
>  			spi->mode |= SPI_RX_QUAD;
>  			break;
> +		case 8:
> +			spi->mode |= SPI_RX_OCTAL;
> +			break;
>  		default:
>  			dev_warn(&ctlr->dev,
>  				"spi-rx-bus-width %d not supported\n",
> diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
> index a64235e..2d21307 100644
> --- a/include/linux/spi/spi.h
> +++ b/include/linux/spi/spi.h
> @@ -163,6 +163,8 @@ struct spi_device {
>  #define	SPI_TX_QUAD	0x200			/* transmit with 4 wires */
>  #define	SPI_RX_DUAL	0x400			/* receive with 2 wires */
>  #define	SPI_RX_QUAD	0x800			/* receive with 4 wires */
> +#define	SPI_TX_OCTAL	0x1000			/* transmit with 8 wires */
> +#define	SPI_RX_OCTAL	0x2000			/* receive with 8 wires */
>  	int			irq;
>  	void			*controller_state;
>  	void			*controller_data;

You're still not updating spi-mem.c to check those flags and
SPI_MEM_MAX_BUSWIDTH is not updated to match the new limit (8 instead
of 4).

Regards,

Boris