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-rw-r--r--arch/arm/mach-omap2/dpll44xx.c41
1 files changed, 41 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/dpll44xx.c b/arch/arm/mach-omap2/dpll44xx.c
index 4613f1e86988..535822fcf4bb 100644
--- a/arch/arm/mach-omap2/dpll44xx.c
+++ b/arch/arm/mach-omap2/dpll44xx.c
@@ -207,3 +207,44 @@ out:
return dd->last_rounded_rate;
}
+
+/**
+ * omap4_dpll_regm4xen_determine_rate - determine rate for a DPLL
+ * @hw: pointer to the clock to determine rate for
+ * @rate: target rate for the DPLL
+ * @best_parent_rate: pointer for returning best parent rate
+ * @best_parent_clk: pointer for returning best parent clock
+ *
+ * Determines which DPLL mode to use for reaching a desired rate.
+ * Checks whether the DPLL shall be in bypass or locked mode, and if
+ * locked, calculates the M,N values for the DPLL via round-rate.
+ * Returns a positive clock rate with success, negative error value
+ * in failure.
+ */
+long omap4_dpll_regm4xen_determine_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *best_parent_rate,
+ struct clk **best_parent_clk)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ struct dpll_data *dd;
+
+ if (!hw || !rate)
+ return -EINVAL;
+
+ dd = clk->dpll_data;
+ if (!dd)
+ return -EINVAL;
+
+ if (__clk_get_rate(dd->clk_bypass) == rate &&
+ (dd->modes & (1 << DPLL_LOW_POWER_BYPASS))) {
+ *best_parent_clk = dd->clk_bypass;
+ } else {
+ rate = omap4_dpll_regm4xen_round_rate(hw, rate,
+ best_parent_rate);
+ *best_parent_clk = dd->clk_ref;
+ }
+
+ *best_parent_rate = rate;
+
+ return rate;
+}