On Wed, 15 Mar 2017, Philipp Zabel wrote:
> As of commit bb475230b8e5 ("reset: make optional functions really
> optional"), the reset framework API calls use NULL pointers to describe
> optional, non-present reset controls.
What does it use to describe genuine errors?
> This allows to return errors from devm_reset_control_get_optional_shared
> unconditionally.
>
> Signed-off-by: Philipp Zabel <p.za...@pengutronix.de>
> ---
> drivers/usb/host/ehci-st.c | 8 ++------
> 1 file changed, 2 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/usb/host/ehci-st.c b/drivers/usb/host/ehci-st.c
> index be4a2788fc582..12e803d2c98df 100644
> --- a/drivers/usb/host/ehci-st.c
> +++ b/drivers/usb/host/ehci-st.c
> @@ -210,18 +210,14 @@ static int st_ehci_platform_probe(struct
> platform_device *dev)
> devm_reset_control_get_optional_shared(&dev->dev, "power");
> if (IS_ERR(priv->pwr)) {
> err = PTR_ERR(priv->pwr);
> - if (err == -EPROBE_DEFER)
> - goto err_put_clks;
> - priv->pwr = NULL;
> + goto err_put_clks;
> }
>
> priv->rst =
> devm_reset_control_get_optional_shared(&dev->dev, "softreset");
> if (IS_ERR(priv->rst)) {
> err = PTR_ERR(priv->rst);
> - if (err == -EPROBE_DEFER)
> - goto err_put_clks;
> - priv->rst = NULL;
> + goto err_put_clks;
> }
>
> if (pdata->power_on) {
These changes do not agree with the patch description. If any sort of
error besides EPROBE_DEFER occurs then:
the old code sets priv->pwr or priv->rst to NULL and continues;
the new code returns with an error.
The only way the patch could be equivalent to the existing code would
be if devm_reset_control_get_optional_shared() returns no errors other
than EPROBE_DEFER. But the patch description doesn't say this.
Alan Stern
