MLK-12284-1 regmap: regmap-mmio: make clk_id optionally when getting clock

According to clock framework, the clk_id could be NULL when getting clock.
But current code relies on a non null clk_id to get clock.
Changing the code to allow a null clk_id to get clock to make it more
reasonable to use.
And the regmap_mmio_gen_context will try to get clock by default but ignore
error if not finding the clock in case some regmap access not reply on
a specific clock.

Signed-off-by: Dong Aisheng <b29396@freescale.com>
(cherry picked from commit a60a38a5285ab27814f261ed39653c55a0a6e24b)

1 files changed, 8 insertions, 12 deletions

diff --git a/drivers/base/regmap/regmap-mmio.c b/drivers/base/regmap/regmap-mmio.c
index 04a329a377e9..ea4651783f97 100644
--- a/drivers/base/regmap/regmap-mmio.c
+++ b/drivers/base/regmap/regmap-mmio.c
@@ -273,19 +273,15 @@ static struct regmap_mmio_context *regmap_mmio_gen_context(struct device *dev,
 	ctx->pad_bytes = config->pad_bits / 8;
 	ctx->clk = ERR_PTR(-ENODEV);
 
-	if (clk_id == NULL)
-		return ctx;
-
 	ctx->clk = clk_get(dev, clk_id);
-	if (IS_ERR(ctx->clk)) {
-		ret = PTR_ERR(ctx->clk);
-		goto err_free;
-	}
-
-	ret = clk_prepare(ctx->clk);
-	if (ret < 0) {
-		clk_put(ctx->clk);
-		goto err_free;
+	if (!IS_ERR(ctx->clk)) {
+		ret = clk_prepare(ctx->clk);
+		if (ret < 0) {
+			clk_put(ctx->clk);
+			goto err_free;
+		}
+	} else {
+		ctx->clk = NULL;
 	}
 
 	return ctx;