linux-kernel - [PATCH] clk: Simplify __of_clk_get_hw_from

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Date:   Thu, 25 Aug 2016 13:35:36 -0700
From:   Stephen Boyd <sboyd@...eaurora.org>
To:     Michael Turquette <mturquette@...libre.com>,
        Stephen Boyd <sboyd@...eaurora.org>
Cc:     Masahiro Yamada <yamada.masahiro@...ionext.com>,
        linux-kernel@...r.kernel.org, linux-clk@...r.kernel.org
Subject: [PATCH] clk: Simplify __of_clk_get_hw_from_provider()

__of_clk_get_hw_from_provider() is confusing because it will
return EPROBE_DEFER if there isn't a ->get() or ->get_hw()
function pointer in a provider. That's just a bug though, and we
used to NULL pointer exception when ->get() was missing anyway,
so let's make this more obvious that they're not optional. The
assumption is that most providers will implement ->get_hw() so we
only fallback to the ->get() function if necessary. This
clarifies the intent and removes any possibility of probe defer
happening if clk providers are buggy.

Reported-by: Masahiro Yamada <yamada.masahiro@...ionext.com>
Signed-off-by: Stephen Boyd <sboyd@...eaurora.org>
---
 drivers/clk/clk.c | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 71cc56712666..d3d26148cdfb 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -3174,19 +3174,14 @@ __of_clk_get_hw_from_provider(struct of_clk_provider *provider,
 			      struct of_phandle_args *clkspec)
 {
 	struct clk *clk;
-	struct clk_hw *hw = ERR_PTR(-EPROBE_DEFER);
 
-	if (provider->get_hw) {
-		hw = provider->get_hw(clkspec, provider->data);
-	} else if (provider->get) {
-		clk = provider->get(clkspec, provider->data);
-		if (!IS_ERR(clk))
-			hw = __clk_get_hw(clk);
-		else
-			hw = ERR_CAST(clk);
-	}
+	if (provider->get_hw)
+		return provider->get_hw(clkspec, provider->data);
 
-	return hw;
+	clk = provider->get(clkspec, provider->data);
+	if (IS_ERR(clk))
+		return ERR_CAST(clk);
+	return __clk_get_hw(clk);
 }
 
 struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec,
-- 
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