Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider: - [Medium] drm/bridge: analogix_dp: dead error check on analogix_dp_init_analog_func() --
commit 84ec40424622aaaaa038f462b132aaae0d50ac8c Author: laixiangwu <[email protected]> drm/bridge: analogix_dp: Fix runtime PM refcount leak in set_bridge() This commit changes the error path after analogix_dp_init_analog_func() in analogix_dp_set_bridge() to jump to out_dp_init so pm_runtime_put_sync() is called on failure. > drm/bridge: analogix_dp: Fix runtime PM refcount leak in set_bridge() > > analogix_dp_set_bridge() calls pm_runtime_get_sync() to power up the > DP core, but if the subsequent analogix_dp_init_analog_func() fails it > returns the error directly, without the matching pm_runtime_put_sync(). > The two other error paths in the function already jump to the > out_dp_init label, which drops the reference. > > Every failed bridge enable therefore increments the runtime PM usage > counter, and repeated failures (e.g. during hotplug storms) prevent > the device from ever runtime suspending again. > > Jump to out_dp_init like the other error paths so the runtime PM > reference is released. > > Fixes: 3efe2ace7f5b ("drm/bridge: analogix_dp: move basic controller init > into runtime PM") > Signed-off-by: laixiangwu <[email protected]> > > diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > index 6df6963740d2c..c9c1375a93182 100644 > --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > @@ -998,7 +998,7 @@ static int analogix_dp_set_bridge(struct > analogix_dp_device *dp) > > ret = analogix_dp_init_analog_func(dp); > if (ret) > - return ret; > + goto out_dp_init; [Severity: Medium] Can analogix_dp_init_analog_func() actually fail here? In commit 917c8d192ba6ad ("drm/bridge: analogix_dp: don't wait for PLL lock too early"), which landed in the same series as commit 3efe2ace7f5b, the PLL lock polling loop and the only error return (-ETIMEDOUT) were removed from analogix_dp_init_analog_func() in drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c: int analogix_dp_init_analog_func(struct analogix_dp_device *dp) { u32 reg; analogix_dp_set_analog_power_down(dp, POWER_ALL, 0); reg = PLL_LOCK_CHG; writel(reg, dp->reg_base + ANALOGIX_DP_COMMON_INT_STA_1); reg = readl(dp->reg_base + ANALOGIX_DP_DEBUG_CTL); reg &= ~(F_PLL_LOCK | PLL_LOCK_CTRL); writel(reg, dp->reg_base + ANALOGIX_DP_DEBUG_CTL); /* Power up PLL */ analogix_dp_set_pll_power_down(dp, 0); /* Enable Serdes FIFO function and Link symbol clock domain module */ reg = readl(dp->reg_base + ANALOGIX_DP_FUNC_EN_2); reg &= ~(SERDES_FIFO_FUNC_EN_N | LS_CLK_DOMAIN_FUNC_EN_N | AUX_FUNC_EN_N); writel(reg, dp->reg_base + ANALOGIX_DP_FUNC_EN_2); return 0; } Because analogix_dp_init_analog_func() only performs register reads/writes and void helper calls, it unconditionally returns 0, while the two functions in analogix_dp_set_bridge() that can fail at runtime (analogix_dp_detect_hpd() and analogix_dp_commit()) already jump to out_dp_init. Since this error branch is unreachable and no runtime PM refcount leak can occur, would it be better to change analogix_dp_init_analog_func() in drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c and drivers/gpu/drm/bridge/analogix/analogix_dp_core.h to return void (matching analogix_dp_init_dp() and the other analogix_dp_init_*() helpers) and drop the dead error check in analogix_dp_set_bridge()? -- Sashiko AI review ยท https://sashiko.dev/#/patchset/[email protected]?part=1
