drm/tilcdc fixing i2c/slave initialization race
In certain senarios drm will initialize before i2c this means that i2c
slave devices like the nxp tda998x will fail to be probed. This patch
detects this condition then defers the probe of the slave device and
the tilcdc main driver.
Signed-off-by: Darren Etheridge <detheridge@ti.com>
Acked-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_drv.c b/drivers/gpu/drm/tilcdc/tilcdc_drv.c
index 1e8f273..40b71da 100644
--- a/drivers/gpu/drm/tilcdc/tilcdc_drv.c
+++ b/drivers/gpu/drm/tilcdc/tilcdc_drv.c
@@ -26,6 +26,7 @@
#include "drm_fb_helper.h"
static LIST_HEAD(module_list);
+static bool slave_probing;
void tilcdc_module_init(struct tilcdc_module *mod, const char *name,
const struct tilcdc_module_ops *funcs)
@@ -41,6 +42,11 @@
list_del(&mod->list);
}
+void tilcdc_slave_probedefer(bool defered)
+{
+ slave_probing = defered;
+}
+
static struct of_device_id tilcdc_of_match[];
static struct drm_framebuffer *tilcdc_fb_create(struct drm_device *dev,
@@ -580,6 +586,10 @@
return -ENXIO;
}
+ /* defer probing if slave is in deferred probing */
+ if (slave_probing == true)
+ return -EPROBE_DEFER;
+
return drm_platform_init(&tilcdc_driver, pdev);
}