clk: Add a basic multiplier clock
Some clocks are using a multiplier component, however, unlike their mux,
gate or divider counterpart, these factors don't have a basic clock
implementation.
This leads to code duplication across platforms that want to use that kind
of clocks, and the impossibility to use the composite clocks with such a
clock without defining your own rate operations.
Create such a driver in order to remove these issues, and hopefully factor
the implementations, reducing code size across platforms and consolidating
the various implementations.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index 3ecc07d..6a7dfe3 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -518,6 +518,48 @@
void __iomem *reg, u8 mshift, u8 mwidth, u8 nshift, u8 nwidth,
u8 clk_divider_flags, spinlock_t *lock);
+/**
+ * struct clk_multiplier - adjustable multiplier clock
+ *
+ * @hw: handle between common and hardware-specific interfaces
+ * @reg: register containing the multiplier
+ * @shift: shift to the multiplier bit field
+ * @width: width of the multiplier bit field
+ * @lock: register lock
+ *
+ * Clock with an adjustable multiplier affecting its output frequency.
+ * Implements .recalc_rate, .set_rate and .round_rate
+ *
+ * Flags:
+ * CLK_MULTIPLIER_ZERO_BYPASS - By default, the multiplier is the value read
+ * from the register, with 0 being a valid value effectively
+ * zeroing the output clock rate. If CLK_MULTIPLIER_ZERO_BYPASS is
+ * set, then a null multiplier will be considered as a bypass,
+ * leaving the parent rate unmodified.
+ * CLK_MULTIPLIER_ROUND_CLOSEST - Makes the best calculated divider to be
+ * rounded to the closest integer instead of the down one.
+ */
+struct clk_multiplier {
+ struct clk_hw hw;
+ void __iomem *reg;
+ u8 shift;
+ u8 width;
+ u8 flags;
+ spinlock_t *lock;
+};
+
+#define CLK_MULTIPLIER_ZERO_BYPASS BIT(0)
+#define CLK_MULTIPLIER_ROUND_CLOSEST BIT(1)
+
+extern const struct clk_ops clk_multiplier_ops;
+
+struct clk *clk_register_multiplier(struct device *dev, const char *name,
+ const char *parent_name,
+ unsigned long flags,
+ void __iomem *reg, u8 shift, u8 width,
+ u8 clk_mult_flags, spinlock_t *lock);
+void clk_unregister_multiplier(struct clk *clk);
+
/***
* struct clk_composite - aggregate clock of mux, divider and gate clocks
*