Re: [PATCH/RESEND] clocksource/arm_arch_timer: Map frame with of_io_request_and_map()

From: Marc Zyngier
Date: Wed Oct 19 2016 - 05:06:49 EST


On 19/10/16 00:45, Stephen Boyd wrote:
> Let's use the of_io_request_and_map() API so that the frame
> region is protected and shows up in /proc/iomem.
>
> Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
> ---
> drivers/clocksource/arm_arch_timer.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
> index 73c487da6d2a..cbfa3bc5be75 100644
> --- a/drivers/clocksource/arm_arch_timer.c
> +++ b/drivers/clocksource/arm_arch_timer.c
> @@ -964,7 +964,8 @@ static int __init arch_timer_mem_init(struct device_node *np)
> }
>
> ret= -ENXIO;
> - base = arch_counter_base = of_iomap(best_frame, 0);
> + base = arch_counter_base = of_io_request_and_map(best_frame, 0,
> + "arch_mem_timer");
> if (!base) {
> pr_err("arch_timer: Can't map frame's registers\n");
> goto out;
>

Careful here: of_io_request_and_map() returns an ERR_PTR() on failure,
while of_iomap just returns NULL. You want to change the error handling
if you're going down that road.

Thanks,

M.
--
Jazz is not dead. It just smells funny...