Re: [PATCH -next] usb: host: drop pointless static qualifier

From: Alan Stern
Date: Wed Jan 23 2019 - 11:09:33 EST


On Wed, 23 Jan 2019, YueHaibing wrote:

> There is no need to have the 'dummy_mask' variable static since new
> value always be assigned before use it.
>
> Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>
> ---
> drivers/usb/host/ehci-ps3.c | 2 +-
> drivers/usb/host/ohci-ps3.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/usb/host/ehci-ps3.c b/drivers/usb/host/ehci-ps3.c
> index 454d8c6..91cee02 100644
> --- a/drivers/usb/host/ehci-ps3.c
> +++ b/drivers/usb/host/ehci-ps3.c
> @@ -86,7 +86,7 @@ static int ps3_ehci_probe(struct ps3_system_bus_device *dev)
> int result;
> struct usb_hcd *hcd;
> unsigned int virq;
> - static u64 dummy_mask;
> + u64 dummy_mask;
>
> if (usb_disabled()) {
> result = -ENODEV;
> diff --git a/drivers/usb/host/ohci-ps3.c b/drivers/usb/host/ohci-ps3.c
> index 395f9d3..a1c1bdf 100644
> --- a/drivers/usb/host/ohci-ps3.c
> +++ b/drivers/usb/host/ohci-ps3.c
> @@ -69,7 +69,7 @@ static int ps3_ohci_probe(struct ps3_system_bus_device *dev)
> int result;
> struct usb_hcd *hcd;
> unsigned int virq;
> - static u64 dummy_mask;
> + u64 dummy_mask;
>
> if (usb_disabled()) {
> result = -ENODEV;

No. You need to read the code and understand how a variable is used
before you decide to modify it.

In this case, a suitable approach would be to change the declaration
so that it says:

status u64 dummy_mask = DMA_BIT_MASK(32);

and remove the line that does the assignment dynamically.

Alan Stern