[U-Boot] [PATCH] gpio: dwapb_gpio: Add reset ctrl to driver

Marek Vasut marex at denx.de
Wed Aug 15 10:11:21 UTC 2018


On 08/15/2018 08:05 PM, Ley Foon Tan wrote:
> Add code to reset all reset signals as in gpio DT node. A reset property
> is an optional feature, so only print out a warning and do not fail if a
> reset property is not present.
> 
> If a reset property is discovered, then use it to deassert, thus
> bringing the IP out of reset.
> 
> Signed-off-by: Ley Foon Tan <ley.foon.tan at intel.com>
> ---
>  drivers/gpio/dwapb_gpio.c | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
> 
> diff --git a/drivers/gpio/dwapb_gpio.c b/drivers/gpio/dwapb_gpio.c
> index 3b5c181..e2b6e69 100644
> --- a/drivers/gpio/dwapb_gpio.c
> +++ b/drivers/gpio/dwapb_gpio.c
> @@ -15,6 +15,7 @@
>  #include <dm/lists.h>
>  #include <dm/root.h>
>  #include <errno.h>
> +#include <reset.h>
>  
>  DECLARE_GLOBAL_DATA_PTR;
>  
> @@ -114,6 +115,20 @@ static int gpio_dwapb_probe(struct udevice *dev)
>  	return 0;
>  }
>  
> +static void gpio_dwapb_reset(struct udevice *dev)
> +{
> +	struct reset_ctl_bulk reset_bulk;
> +	int ret;
> +
> +	ret = reset_get_bulk(dev, &reset_bulk);
> +	if (ret) {
> +		dev_warn(dev, "Can't get reset: %d\n", ret);
> +		return;
> +	}
> +
> +	reset_deassert_bulk(&reset_bulk);
> +}
> +
>  static int gpio_dwapb_bind(struct udevice *dev)
>  {
>  	struct gpio_dwapb_platdata *plat = dev_get_platdata(dev);
> @@ -126,6 +141,8 @@ static int gpio_dwapb_bind(struct udevice *dev)
>  	if (plat)
>  		return 0;
>  
> +	gpio_dwapb_reset(dev);

This should be done in probe, not bind. Also, it should be undone in
.remove.

>  	base = dev_read_addr(dev);
>  	if (base == FDT_ADDR_T_NONE) {
>  		debug("Can't get the GPIO register base address\n");
> 


-- 
Best regards,
Marek Vasut


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