Re: [PATCH v3 1/4] spi: bcm63xx-spi: add reset support

Florian Fainelli
2020-06-16T17:05:17Z

On 6/16/2020 12:02 AM, Álvaro Fernández Rojas wrote:
> bcm63xx arch resets the SPI controller at early boot. However, bmips arch
> needs to perform a reset when probing the driver.
>
> Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
> Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
> ---
> v3: use devm_reset_control_get_optional_exclusive
> v2: use devm_reset_control_get_exclusive
>
> drivers/spi/spi-bcm63xx.c | 17 +++++++++++++++++
> 1 file changed, 17 insertions(+)
>
> diff --git a/drivers/spi/spi-bcm63xx.c b/drivers/spi/spi-bcm63xx.c
> index 0f1b10a4ef0c..92e88901189c 100644
> --- a/drivers/spi/spi-bcm63xx.c
> +++ b/drivers/spi/spi-bcm63xx.c
> @@ -18,6 +18,7 @@
> #include <linux/err.h>
> #include <linux/pm_runtime.h>
> #include <linux/of.h>
> +#include <linux/reset.h>
>
> /* BCM 6338/6348 SPI core */
> #define SPI_6348_RSET_SIZE 64
> @@ -493,6 +494,7 @@ static int bcm63xx_spi_probe(struct platform_device *pdev)
> struct bcm63xx_spi *bs;
> int ret;
> u32 num_cs = BCM63XX_SPI_MAX_CS;
> + struct reset_control *reset;
>
> if (dev->of_node) {
> const struct of_device_id *match;
> @@ -529,6 +531,15 @@ static int bcm63xx_spi_probe(struct platform_device *pdev)
> return PTR_ERR(clk);
> }
>
> + reset = devm_reset_control_get_optional_exclusive(dev, NULL);
> + if (IS_ERR(reset)) {
> + ret = PTR_ERR(reset);
> + if (ret != -EPROBE_DEFER)
> + dev_err(dev,
> + "failed to get reset controller: %d\n", ret);
> + return ret;
> + }

When the controller is optional, you don't need to do that manual error
checking, as it does that for you already. You can only do:

if (IS_ERR(reset))
return PTR_ERR(reset);

and that's it. With that fixed in v4, you can add:

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
--
Florian