[GIT PULL 14/15] intel_th: Add global activate/deactivate callbacks for the glue layers

[Alexander Shishkin]

A glue layer may want to install its own hooks into trace capture start
and stop paths to apply workarounds. This adds optional callbacks.

Signed-off-by: Alexander Shishkin <alexander.shish...@linux.intel.com>
---
 drivers/hwtracing/intel_th/core.c     | 26 ++++++++++++++++++++++----
 drivers/hwtracing/intel_th/intel_th.h |  2 ++
 2 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/drivers/hwtracing/intel_th/core.c 
b/drivers/hwtracing/intel_th/core.c
index e915ab24f4..998e3e5507 100644
--- a/drivers/hwtracing/intel_th/core.c
+++ b/drivers/hwtracing/intel_th/core.c
@@ -226,6 +226,7 @@ static int intel_th_output_activate(struct intel_th_device 
*thdev)
 {
        struct intel_th_driver *thdrv =
                to_intel_th_driver_or_null(thdev->dev.driver);
+       struct intel_th *th = to_intel_th(thdev);
        int ret = 0;
 
        if (!thdrv)
@@ -236,15 +237,28 @@ static int intel_th_output_activate(struct 
intel_th_device *thdev)
 
        pm_runtime_get_sync(&thdev->dev);
 
+       if (th->activate)
+               ret = th->activate(th);
+       if (ret)
+               goto fail_put;
+
        if (thdrv->activate)
                ret = thdrv->activate(thdev);
        else
                intel_th_trace_enable(thdev);
 
-       if (ret) {
-               pm_runtime_put(&thdev->dev);
-               module_put(thdrv->driver.owner);
-       }
+       if (ret)
+               goto fail_deactivate;
+
+       return 0;
+
+fail_deactivate:
+       if (th->deactivate)
+               th->deactivate(th);
+
+fail_put:
+       pm_runtime_put(&thdev->dev);
+       module_put(thdrv->driver.owner);
 
        return ret;
 }
@@ -253,6 +267,7 @@ static void intel_th_output_deactivate(struct 
intel_th_device *thdev)
 {
        struct intel_th_driver *thdrv =
                to_intel_th_driver_or_null(thdev->dev.driver);
+       struct intel_th *th = to_intel_th(thdev);
 
        if (!thdrv)
                return;
@@ -262,6 +277,9 @@ static void intel_th_output_deactivate(struct 
intel_th_device *thdev)
        else
                intel_th_trace_disable(thdev);
 
+       if (th->deactivate)
+               th->deactivate(th);
+
        pm_runtime_put(&thdev->dev);
        module_put(thdrv->driver.owner);
 }
diff --git a/drivers/hwtracing/intel_th/intel_th.h 
b/drivers/hwtracing/intel_th/intel_th.h
index 68244602ca..78a4fb28b1 100644
--- a/drivers/hwtracing/intel_th/intel_th.h
+++ b/drivers/hwtracing/intel_th/intel_th.h
@@ -263,6 +263,8 @@ struct intel_th {
        struct intel_th_drvdata *drvdata;
 
        struct resource         *resource;
+       int                     (*activate)(struct intel_th *);
+       void                    (*deactivate)(struct intel_th *);
        unsigned int            num_thdevs;
        unsigned int            num_resources;
        int                     irq;
-- 
2.14.1