linux-kernel - [PATCH v2 1/3] clk: generalize devm_clk

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Message-Id: <20210301110821.1445756-2-uwe@kleine-koenig.org>
Date:   Mon,  1 Mar 2021 12:08:19 +0100
From:   Uwe Kleine-König <uwe@...ine-koenig.org>
To:     Michael Turquette <mturquette@...libre.com>,
        Stephen Boyd <sboyd@...nel.org>
Cc:     linux-pwm@...r.kernel.org, linux-clk@...r.kernel.org,
        kernel@...gutronix.de, linux-kernel@...r.kernel.org,
        Uwe Kleine-König 
        <u.kleine-koenig@...gutronix.de>
Subject: [PATCH v2 1/3] clk: generalize devm_clk_get() a bit

From: Uwe Kleine-König <u.kleine-koenig@...gutronix.de>

Allow to add an exit hook to devm managed clocks. Also use
clk_get_optional() in devm_clk_get_optional instead of open coding it.
The generalisation will be used in the next commit to add some more
devm_clk helpers.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@...gutronix.de>
---
 drivers/clk/clk-devres.c | 75 +++++++++++++++++++++++++++++-----------
 1 file changed, 54 insertions(+), 21 deletions(-)

diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c
index be160764911b..7ba8670deeb6 100644
--- a/drivers/clk/clk-devres.c
+++ b/drivers/clk/clk-devres.c
@@ -4,39 +4,72 @@
 #include <linux/export.h>
 #include <linux/gfp.h>
 
+struct devm_clk_state {
+	struct clk *clk;
+	void (*exit)(struct clk *clk);
+};
+
 static void devm_clk_release(struct device *dev, void *res)
 {
-	clk_put(*(struct clk **)res);
+	struct devm_clk_state *state = *(struct devm_clk_state **)res;
+
+	if (state->exit)
+		state->exit(state->clk);
+
+	clk_put(state->clk);
+}
+
+struct clk *__devm_clk_get(struct device *dev, const char *id,
+			   struct clk *(*get)(struct device *dev, const char *id),
+			   int (*init)(struct clk *clk),
+			   void (*exit)(struct clk *clk))
+{
+	struct devm_clk_state *state;
+	struct clk *clk;
+	int ret;
+
+	state = devres_alloc(devm_clk_release, sizeof(*state), GFP_KERNEL);
+	if (!state)
+		return ERR_PTR(-ENOMEM);
+
+	clk = get(dev, id);
+	if (IS_ERR(clk)) {
+		ret = PTR_ERR(clk);
+		goto err_clk_get;
+	}
+
+	if (init) {
+		ret = init(clk);
+		if (ret)
+			goto err_clk_init;
+	}
+
+	state->clk = clk;
+	state->exit = exit;
+
+	devres_add(dev, state);
+
+	return clk;
+
+err_clk_init:
+
+	clk_put(clk);
+err_clk_get:
+
+	devres_free(state);
+	return ERR_PTR(ret);
 }
 
 struct clk *devm_clk_get(struct device *dev, const char *id)
 {
-	struct clk **ptr, *clk;
+	return __devm_clk_get(dev, id, clk_get, NULL, NULL);
 
-	ptr = devres_alloc(devm_clk_release, sizeof(*ptr), GFP_KERNEL);
-	if (!ptr)
-		return ERR_PTR(-ENOMEM);
-
-	clk = clk_get(dev, id);
-	if (!IS_ERR(clk)) {
-		*ptr = clk;
-		devres_add(dev, ptr);
-	} else {
-		devres_free(ptr);
-	}
-
-	return clk;
 }
 EXPORT_SYMBOL(devm_clk_get);
 
 struct clk *devm_clk_get_optional(struct device *dev, const char *id)
 {
-	struct clk *clk = devm_clk_get(dev, id);
-
-	if (clk == ERR_PTR(-ENOENT))
-		return NULL;
-
-	return clk;
+	return __devm_clk_get(dev, id, clk_get_optional, NULL, NULL);
 }
 EXPORT_SYMBOL(devm_clk_get_optional);
 
-- 
2.30.0