clk: Add is_enabled callback

This allows us to better detect whether a clk is enabled or not.

- If we can ask a clk, ask it. If it's enabled, go on and ask parents
- If we can't ask it, but it can be enabled, depend on the enable_count.
  if it's positive, go on and ask parents
- If we can't ask it and it cannot be enabled, assume it is enabled
  and ask parents.

This makes the CLK_ALWAYS_ENABLED unnecessary, since the fixed clk now
always returns 1 in its is_enabled callback.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 14 insertions, 0 deletions

diff --git a/drivers/clk/clk-gate.c b/drivers/clk/clk-gate.c
index cf1bb1af62..a455094b69 100644
--- a/drivers/clk/clk-gate.c
+++ b/drivers/clk/clk-gate.c
@@ -49,9 +49,23 @@ static void clk_gate_disable(struct clk *clk)
 	writel(val, g->reg);
 }
 
+static int clk_gate_is_enabled(struct clk *clk)
+{
+	struct clk_gate *g = container_of(clk, struct clk_gate, clk);
+	u32 val;
+
+	val = readl(g->reg);
+
+	if (val & (1 << g->shift))
+		return 1;
+	else
+		return 0;
+}
+
 struct clk_ops clk_gate_ops = {
 	.enable = clk_gate_enable,
 	.disable = clk_gate_disable,
+	.is_enabled = clk_gate_is_enabled,
 };
 
 struct clk *clk_gate(const char *name, const char *parent, void __iomem *reg,