[PATCH] ARM: EXYNOS: Fix dereference of ERR_PTR returned by of_genpd_get_from_provider

[Krzysztof Kozlowski]

ERR_PTR was dereferenced during sub domain parsing, if parent domain
could not be obtained (because of invalid phandle or deferred
registration of parent domain).

The Exynos power domain code checked whether
of_genpd_get_from_provider() returned NULL and in that case it skipped
that power domain node. However this function returns ERR_PTR or valid
pointer, not NULL.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski at samsung.com>
Cc: <stable at vger.kernel.org>
Fixes: 0f7807518fe1 ("ARM: EXYNOS: add support for sub-power domains")

---

The patchset is rebased on top of my fixes for pm_domains.c to avoid the
conflicts:
https://lkml.org/lkml/2015/3/27/321
---
 arch/arm/mach-exynos/pm_domains.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mach-exynos/pm_domains.c b/arch/arm/mach-exynos/pm_domains.c
index 1a90c5da2fd7..440324c94d28 100644
--- a/arch/arm/mach-exynos/pm_domains.c
+++ b/arch/arm/mach-exynos/pm_domains.c
@@ -209,7 +209,7 @@ no_clk:
 		args.np = np;
 		args.args_count = 0;
 		child_domain = of_genpd_get_from_provider(&args);
-		if (!child_domain)
+		if (IS_ERR(child_domain))
 			goto next_pd;
 
 		if (of_parse_phandle_with_args(np, "power-domains",
@@ -217,7 +217,7 @@ no_clk:
 			goto next_pd;
 
 		parent_domain = of_genpd_get_from_provider(&args);
-		if (!parent_domain)
+		if (IS_ERR(parent_domain))
 			goto next_pd;
 
 		if (pm_genpd_add_subdomain(parent_domain, child_domain))
-- 
1.9.1