VIA_WAIT_ON() is a direct copy of DRM_WAIT_ON() from drm_os_linux.h. The copy is made so we can avoid the dependency on the legacy header. A more involved approach had been to introduce wait_event_* but for this legacy driver the simpler and more safe approach with a copy of the macro was selected. Added the relevant header files for the functions used in VIA_WAIT_ON.
Users of the macro will come in a follow-up patch. Signed-off-by: Sam Ravnborg <[email protected]> Cc: Kevin Brace <[email protected]> Cc: Thomas Hellstrom <[email protected]> Cc: "Gustavo A. R. Silva" <[email protected]> Cc: Mike Marshall <[email protected]> Cc: Ira Weiny <[email protected]> Cc: Daniel Vetter <[email protected]> Cc: Emil Velikov <[email protected]> Cc: Michel Dänzer <[email protected]> --- drivers/gpu/drm/via/via_drv.h | 42 ++++++++++++++++++++++++++++++++++- 1 file changed, 41 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/via/via_drv.h b/drivers/gpu/drm/via/via_drv.h index d5a2b1ffd8c1..664b7f8a20c4 100644 --- a/drivers/gpu/drm/via/via_drv.h +++ b/drivers/gpu/drm/via/via_drv.h @@ -24,8 +24,13 @@ #ifndef _VIA_DRV_H_ #define _VIA_DRV_H_ -#include <drm/drm_mm.h> +#include <linux/jiffies.h> +#include <linux/sched.h> +#include <linux/sched/signal.h> +#include <linux/wait.h> + #include <drm/drm_legacy.h> +#include <drm/drm_mm.h> #define DRIVER_AUTHOR "Various" @@ -127,6 +132,41 @@ enum via_family { #define VIA_WRITE8(reg, val) \ writeb(val, ((void __iomem *)VIA_BASE->handle) + (reg)) +/* + * Poll in a loop waiting for 'contidition' to be true. + * Note: A direct replacement with wait_event_interruptible_timeout() + * will not work unless driver is updated to emit wake_up() + * in relevant places that can impact the 'condition' + * + * Returns: + * ret keeps current value if 'condition' becomes true + * ret = -BUSY if timeout happens + * ret = -EINTR if a signal interrupted the waiting period + */ +#define VIA_WAIT_ON( ret, queue, timeout, condition ) \ +do { \ + DECLARE_WAITQUEUE(entry, current); \ + unsigned long end = jiffies + (timeout); \ + add_wait_queue(&(queue), &entry); \ + \ + for (;;) { \ + __set_current_state(TASK_INTERRUPTIBLE); \ + if (condition) \ + break; \ + if (time_after_eq(jiffies, end)) { \ + ret = -EBUSY; \ + break; \ + } \ + schedule_timeout((HZ/100 > 1) ? HZ/100 : 1); \ + if (signal_pending(current)) { \ + ret = -EINTR; \ + break; \ + } \ + } \ + __set_current_state(TASK_RUNNING); \ + remove_wait_queue(&(queue), &entry); \ +} while (0) + extern const struct drm_ioctl_desc via_ioctls[]; extern int via_max_ioctl; -- 2.20.1 _______________________________________________ dri-devel mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/dri-devel
