Re: [PATCH v1] spi: loopback-test: provide loop request option.

[Uwe Kleine-König]

On Wed, Jul 12, 2017 at 03:40:20PM +0200, Oleksij Rempel wrote:
> From: Oleksij Rempel <linux@xxxxxxxxxxxxxxxx>
> 
> Provide a module parameter to request internal
> loop by the SPI master controller.

> This should make loop testing easier without extra HW modification.
> 
> Signed-off-by: Oleksij Rempel <linux@xxxxxxxxxxxxxxxx>
> ---
>  drivers/spi/spi-loopback-test.c | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/drivers/spi/spi-loopback-test.c b/drivers/spi/spi-loopback-test.c
> index f4875f177df0..34e1544d7d0e 100644
> --- a/drivers/spi/spi-loopback-test.c
> +++ b/drivers/spi/spi-loopback-test.c
> @@ -51,6 +51,14 @@ MODULE_PARM_DESC(loopback,
>  		 "is checked to match tx_buf after the spi_message "	\
>  		 "is executed");
>  
> +/* the device is jumpered for loopback - enabling some rx_buf tests */
> +int loop_req;
> +module_param(loop_req, int, 0);
> +MODULE_PARM_DESC(loop_req,
> +		 "if set enable controller will be asked to enable "	\
> +		 "test loop mode. If supported, MISO and MOSI will be "  \
> +		 "jumpered by SPI controller");
> +
>  /* run only a specific test */
>  int run_only_test = -1;
>  module_param(run_only_test, int, 0);
> @@ -313,6 +321,16 @@ static int spi_loopback_test_probe(struct spi_device *spi)
>  {
>  	int ret;
>  
> +	if (loop_req) {
> +		spi->mode = SPI_LOOP | spi->mode;
> +		ret = spi_setup(spi);
> +		if (ret) {
> +			dev_err(&spi->dev, "SPI setup wasn't successful %d\n", ret);
> +			dev_err(&spi->dev, "SPI_LOOP is not supported by SPI master.");

Why two error messages here? What about:

	dev_err(&spi->dev, "SPI setup with SPI_LOOP failed (%d)\n", ret);

These lines are > 80 chars, so you should break them.

> +			return -ENODEV;

return ret?

Best regards
Uwe

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