Hi Aditya,
(CC'ing Rafael)
Thank you for the patch.
On Sat, Jun 13, 2020 at 09:40:05PM -0500, Aditya Pakki wrote:
On calling pm_runtime_get_sync() the reference count of the device is incremented. In case of failure, decrement the reference count before returning the error.
Signed-off-by: Aditya Pakki pakki001@umn.edu
I've seen lots of similar patches recently. Instead of mass-patching the drivers this way, shouldn't pm_runtime_get_sync() (and similar functions) decrease the refcount on their failure path ? That would require patching drivers that already handle this issue, but I believe that would cause less churn, and more importantly, avoid the issue once and for good for new code.
drivers/gpu/drm/bridge/cdns-dsi.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/bridge/cdns-dsi.c b/drivers/gpu/drm/bridge/cdns-dsi.c index 69c3892caee5..583cb8547106 100644 --- a/drivers/gpu/drm/bridge/cdns-dsi.c +++ b/drivers/gpu/drm/bridge/cdns-dsi.c @@ -788,8 +788,10 @@ static void cdns_dsi_bridge_enable(struct drm_bridge *bridge) u32 tmp, reg_wakeup, div; int nlanes;
- if (WARN_ON(pm_runtime_get_sync(dsi->base.dev) < 0))
if (WARN_ON(pm_runtime_get_sync(dsi->base.dev) < 0)) {
pm_runtime_put(dsi->base.dev);return;
}
mode = &bridge->encoder->crtc->state->adjusted_mode; nlanes = output->dev->lanes;
@@ -1028,8 +1030,10 @@ static ssize_t cdns_dsi_transfer(struct mipi_dsi_host *host, int ret, i, tx_len, rx_len;
ret = pm_runtime_get_sync(host->dev);
- if (ret < 0)
if (ret < 0) {
pm_runtime_put(host->dev);return ret;
}
cdns_dsi_init_link(dsi);