On Tuesday 22 November 2011 02:51 PM, Tomi Valkeinen wrote:
The functions in apply.c, called mostly via function pointers in overlay
and overlay_manager structs, will be divided into two groups. The other
group will not sleep and can be called from interrupts, and the other
group may sleep.
The idea is that the non-sleeping functions may only change certain
settings in overlays and managers, and those settings may only affect
the particular overlay/manager. For example, set the base address of the
overlay.
The blocking functions, however, will handle more complex configuration
changes. For example, when an overlay is enabled and fifo-merge feature
is used, we need to do the enable in multiple steps, waiting in between,
and the change affects multiple overlays and managers.
apply.c already contains a spinlock, which has been used to protect
(badly) the dss_data. This patch adds locks/unlocks of the spinlock to
the missing places, and the lock should now properly protect dss_data.
Signed-off-by: Tomi Valkeinen<tomi.valkeinen@xxxxxx>
---
drivers/video/omap2/dss/apply.c | 29 +++++++++++++++++++++++++++++
1 files changed, 29 insertions(+), 0 deletions(-)
diff --git a/drivers/video/omap2/dss/apply.c b/drivers/video/omap2/dss/apply.c
index fb6d3c2..9ad2a36 100644
--- a/drivers/video/omap2/dss/apply.c
+++ b/drivers/video/omap2/dss/apply.c
@@ -405,6 +405,9 @@ void dss_start_update(struct omap_overlay_manager *mgr)
struct mgr_priv_data *mp = get_mgr_priv(mgr);
struct ovl_priv_data *op;
struct omap_overlay *ovl;
+ unsigned long flags;
+
+ spin_lock_irqsave(&data_lock, flags);
mp->do_manual_update = true;
dss_write_regs();
@@ -418,6 +421,8 @@ void dss_start_update(struct omap_overlay_manager *mgr)
mp->shadow_dirty = false;
dispc_mgr_enable(mgr->id, true);
+
+ spin_unlock_irqrestore(&data_lock, flags);
}
static void dss_apply_irq_handler(void *data, u32 mask);
@@ -662,16 +667,28 @@ void dss_mgr_disable(struct omap_overlay_manager *mgr)
int dss_mgr_set_info(struct omap_overlay_manager *mgr,
struct omap_overlay_manager_info *info)
{
+ unsigned long flags;
+
+ spin_lock_irqsave(&data_lock, flags);
+
mgr->info = *info;
mgr->info_dirty = true;
+ spin_unlock_irqrestore(&data_lock, flags);
+
return 0;
}
void dss_mgr_get_info(struct omap_overlay_manager *mgr,
struct omap_overlay_manager_info *info)
{
+ unsigned long flags;
+
+ spin_lock_irqsave(&data_lock, flags);
+
*info = mgr->info;
+
+ spin_unlock_irqrestore(&data_lock, flags);
}
int dss_mgr_set_device(struct omap_overlay_manager *mgr,
@@ -745,16 +762,28 @@ err:
int dss_ovl_set_info(struct omap_overlay *ovl,
struct omap_overlay_info *info)
{
+ unsigned long flags;
+
+ spin_lock_irqsave(&data_lock, flags);
+
ovl->info = *info;
ovl->info_dirty = true;
+ spin_unlock_irqrestore(&data_lock, flags);
+
return 0;
}
void dss_ovl_get_info(struct omap_overlay *ovl,
struct omap_overlay_info *info)
{
+ unsigned long flags;
+
+ spin_lock_irqsave(&data_lock, flags);
+
*info = ovl->info;
+
+ spin_unlock_irqrestore(&data_lock, flags);
}
The get/set info functions for overlays and managers only modify the
omap_overlay_info or manager_info structs, these aren't really a part of
'dss_data', they only become a part of dss_data only when we call
mgr->apply().
So, are we protecting these functions so that 2 users of the same
overlay don't see incorrect info values?
Archit
int dss_ovl_set_manager(struct omap_overlay *ovl,
--
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