clk: change clk_ops' ->determine_rate() prototype

Clock rates are stored in an unsigned long field, but ->determine_rate()
(which returns a rounded rate from a requested one) returns a long
value (errors are reported using negative error codes), which can lead
to long overflow if the clock rate exceed 2Ghz.

Change ->determine_rate() prototype to return 0 or an error code, and pass
a pointer to a clk_rate_request structure containing the expected target
rate and the rate constraints imposed by clk users.

The clk_rate_request structure might be extended in the future to contain
other kind of constraints like the rounding policy, the maximum clock
inaccuracy or other things that are not yet supported by the CCF
(power consumption constraints ?).

Signed-off-by: Boris Brezillon <[e-mail]>
CC: Jonathan Corbet <[e-mail]>
CC: Tony Lindgren <[e-mail]>
CC: Ralf Baechle <[e-mail]>
CC: "Emilio López" <[e-mail]>
CC: Maxime Ripard <[e-mail]>
Acked-by: Tero Kristo <[e-mail]>
CC: Peter De Schrijver <[e-mail]>
CC: Prashant Gaikwad <[e-mail]>
CC: Stephen Warren <[e-mail]>
CC: Thierry Reding <[e-mail]>
CC: Alexandre Courbot <[e-mail]>
CC: [e-mail]
CC: [e-mail]
CC: [e-mail]
CC: [e-mail]
CC: [e-mail]
CC: [e-mail]
[[e-mail]: Fix parent dereference problem in
__clk_determine_rate()]
Signed-off-by: Stephen Boyd <[e-mail]>
Tested-by: Romain Perier <[e-mail]>
Signed-off-by: Heiko Stuebner <[e-mail]>
[[e-mail]: Folded in fix from Heiko for fixed-rate
clocks without parents or a rate determining op]
Signed-off-by: Stephen Boyd <[e-mail]>

Documentation/clk.txt

···
 		long		(*round_rate)(struct clk_hw *hw,
 						unsigned long rate,
 						unsigned long *parent_rate);
-		long		(*determine_rate)(struct clk_hw *hw,
-						unsigned long rate,
-						unsigned long min_rate,
-						unsigned long max_rate,
-						unsigned long *best_parent_rate,
-						struct clk_hw **best_parent_clk);
+		int		(*determine_rate)(struct clk_hw *hw,
+						  struct clk_rate_request *req);
 		int		(*set_parent)(struct clk_hw *hw, u8 index);
 		u8		(*get_parent)(struct clk_hw *hw);
 		int		(*set_rate)(struct clk_hw *hw,

arch/arm/mach-omap2/dpll3xxx.c

···
 /**
  * omap3_noncore_dpll_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
+ * @req: target rate request
  *
  * Determines which DPLL mode to use for reaching a desired target 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.
+ * Returns a 0 on success, negative error value in failure.
  */
-long omap3_noncore_dpll_determine_rate(struct clk_hw *hw, unsigned long rate,
-				       unsigned long min_rate,
-				       unsigned long max_rate,
-				       unsigned long *best_parent_rate,
-				       struct clk_hw **best_parent_clk)
+int omap3_noncore_dpll_determine_rate(struct clk_hw *hw,
+				      struct clk_rate_request *req)
 {
 	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
 	struct dpll_data *dd;
 
-	if (!hw || !rate)
+	if (!req->rate)
 		return -EINVAL;
 
 	dd = clk->dpll_data;
 	if (!dd)
 		return -EINVAL;
 
-	if (__clk_get_rate(dd->clk_bypass) == rate &&
+	if (__clk_get_rate(dd->clk_bypass) == req->rate &&
 	    (dd->modes & (1 << DPLL_LOW_POWER_BYPASS))) {
-		*best_parent_clk = __clk_get_hw(dd->clk_bypass);
+		req->best_parent_hw = __clk_get_hw(dd->clk_bypass);
 	} else {
-		rate = omap2_dpll_round_rate(hw, rate, best_parent_rate);
-		*best_parent_clk = __clk_get_hw(dd->clk_ref);
+		req->rate = omap2_dpll_round_rate(hw, req->rate,
+					  &req->best_parent_rate);
+		req->best_parent_hw = __clk_get_hw(dd->clk_ref);
 	}
 
-	*best_parent_rate = rate;
+	req->best_parent_rate = req->rate;
 
-	return rate;
+	return 0;
 }
 
 /**

arch/arm/mach-omap2/dpll44xx.c

···
 /**
  * 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
+ * @req: target rate request
  *
  * 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.
+ * Returns 0 on success and a negative error value otherwise.
  */
-long omap4_dpll_regm4xen_determine_rate(struct clk_hw *hw, unsigned long rate,
-					unsigned long min_rate,
-					unsigned long max_rate,
-					unsigned long *best_parent_rate,
-					struct clk_hw **best_parent_clk)
+int omap4_dpll_regm4xen_determine_rate(struct clk_hw *hw,
+				       struct clk_rate_request *req)
 {
 	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
 	struct dpll_data *dd;
 
-	if (!hw || !rate)
+	if (!req->rate)
 		return -EINVAL;
 
 	dd = clk->dpll_data;
 	if (!dd)
 		return -EINVAL;
 
-	if (__clk_get_rate(dd->clk_bypass) == rate &&
+	if (__clk_get_rate(dd->clk_bypass) == req->rate &&
 	    (dd->modes & (1 << DPLL_LOW_POWER_BYPASS))) {
-		*best_parent_clk = __clk_get_hw(dd->clk_bypass);
+		req->best_parent_hw = __clk_get_hw(dd->clk_bypass);
 	} else {
-		rate = omap4_dpll_regm4xen_round_rate(hw, rate,
-						      best_parent_rate);
-		*best_parent_clk = __clk_get_hw(dd->clk_ref);
+		req->rate = omap4_dpll_regm4xen_round_rate(hw, req->rate,
+						&req->best_parent_rate);
+		req->best_parent_hw = __clk_get_hw(dd->clk_ref);
 	}
 
-	*best_parent_rate = rate;
+	req->best_parent_rate = req->rate;
 
-	return rate;
+	return 0;
 }

arch/mips/alchemy/common/clock.c

···
 	return div1;
 }
 
-static long alchemy_clk_fgcs_detr(struct clk_hw *hw, unsigned long rate,
-					unsigned long *best_parent_rate,
-					struct clk_hw **best_parent_clk,
-					int scale, int maxdiv)
+static int alchemy_clk_fgcs_detr(struct clk_hw *hw,
+				 struct clk_rate_request *req,
+				 int scale, int maxdiv)
 {
 	struct clk *pc, *bpc, *free;
 	long tdv, tpr, pr, nr, br, bpr, diff, lastdiff;
···
 		}
 
 		pr = clk_get_rate(pc);
-		if (pr < rate)
+		if (pr < req->rate)
 			continue;
 
 		/* what can hardware actually provide */
-		tdv = alchemy_calc_div(rate, pr, scale, maxdiv, NULL);
+		tdv = alchemy_calc_div(req->rate, pr, scale, maxdiv, NULL);
 		nr = pr / tdv;
-		diff = rate - nr;
-		if (nr > rate)
+		diff = req->rate - nr;
+		if (nr > req->rate)
 			continue;
 
 		if (diff < lastdiff) {
···
 	 */
 	if (lastdiff && free) {
 		for (j = (maxdiv == 4) ? 1 : scale; j <= maxdiv; j += scale) {
-			tpr = rate * j;
+			tpr = req->rate * j;
 			if (tpr < 0)
 				break;
 			pr = clk_round_rate(free, tpr);
 
-			tdv = alchemy_calc_div(rate, pr, scale, maxdiv, NULL);
+			tdv = alchemy_calc_div(req->rate, pr, scale, maxdiv,
+					       NULL);
 			nr = pr / tdv;
-			diff = rate - nr;
-			if (nr > rate)
+			diff = req->rate - nr;
+			if (nr > req->rate)
 				continue;
 			if (diff < lastdiff) {
 				lastdiff = diff;
···
 		}
 	}
 
-	*best_parent_rate = bpr;
-	*best_parent_clk = __clk_get_hw(bpc);
-	return br;
+	req->best_parent_rate = bpr;
+	req->best_parent_hw = __clk_get_hw(bpc);
+	req->rate = br;
+	return 0;
 }
 
 static int alchemy_clk_fgv1_en(struct clk_hw *hw)
···
 	return parent_rate / v;
 }
 
-static long alchemy_clk_fgv1_detr(struct clk_hw *hw, unsigned long rate,
-					unsigned long min_rate,
-					unsigned long max_rate,
-					unsigned long *best_parent_rate,
-					struct clk_hw **best_parent_clk)
+static int alchemy_clk_fgv1_detr(struct clk_hw *hw,
+				 struct clk_rate_request *req)
 {
-	return alchemy_clk_fgcs_detr(hw, rate, best_parent_rate,
-				     best_parent_clk, 2, 512);
+	return alchemy_clk_fgcs_detr(hw, req, 2, 512);
 }
 
 /* Au1000, Au1100, Au15x0, Au12x0 */
···
 	return t;
 }
 
-static long alchemy_clk_fgv2_detr(struct clk_hw *hw, unsigned long rate,
-					unsigned long min_rate,
-					unsigned long max_rate,
-					unsigned long *best_parent_rate,
-					struct clk_hw **best_parent_clk)
+static int alchemy_clk_fgv2_detr(struct clk_hw *hw,
+				 struct clk_rate_request *req)
 {
 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
 	int scale, maxdiv;
···
 		maxdiv = 512;
 	}
 
-	return alchemy_clk_fgcs_detr(hw, rate, best_parent_rate,
-				     best_parent_clk, scale, maxdiv);
+	return alchemy_clk_fgcs_detr(hw, req, scale, maxdiv);
 }
 
 /* Au1300 larger input mux, no separate disable bit, flexible divider */
···
 	return 0;
 }
 
-static long alchemy_clk_csrc_detr(struct clk_hw *hw, unsigned long rate,
-					unsigned long min_rate,
-					unsigned long max_rate,
-					unsigned long *best_parent_rate,
-					struct clk_hw **best_parent_clk)
+static int alchemy_clk_csrc_detr(struct clk_hw *hw,
+				 struct clk_rate_request *req)
 {
 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
 	int scale = c->dt[2] == 3 ? 1 : 2; /* au1300 check */
 
-	return alchemy_clk_fgcs_detr(hw, rate, best_parent_rate,
-				     best_parent_clk, scale, 4);
+	return alchemy_clk_fgcs_detr(hw, req, scale, 4);
 }
 
 static struct clk_ops alchemy_clkops_csrc = {

drivers/clk/at91/clk-programmable.c

···
 	return parent_rate >> pres;
 }
 
-static long clk_programmable_determine_rate(struct clk_hw *hw,
-					    unsigned long rate,
-					    unsigned long min_rate,
-					    unsigned long max_rate,
-					    unsigned long *best_parent_rate,
-					    struct clk_hw **best_parent_hw)
+static int clk_programmable_determine_rate(struct clk_hw *hw,
+					   struct clk_rate_request *req)
 {
 	struct clk *parent = NULL;
 	long best_rate = -EINVAL;
···
 		parent_rate = __clk_get_rate(parent);
 		for (shift = 0; shift < PROG_PRES_MASK; shift++) {
 			tmp_rate = parent_rate >> shift;
-			if (tmp_rate <= rate)
+			if (tmp_rate <= req->rate)
 				break;
 		}
 
-		if (tmp_rate > rate)
+		if (tmp_rate > req->rate)
 			continue;
 
-		if (best_rate < 0 || (rate - tmp_rate) < (rate - best_rate)) {
+		if (best_rate < 0 ||
+		    (req->rate - tmp_rate) < (req->rate - best_rate)) {
 			best_rate = tmp_rate;
-			*best_parent_rate = parent_rate;
-			*best_parent_hw = __clk_get_hw(parent);
+			req->best_parent_rate = parent_rate;
+			req->best_parent_hw = __clk_get_hw(parent);
 		}
 
 		if (!best_rate)
 			break;
 	}
 
-	return best_rate;
+	if (best_rate < 0)
+		return best_rate;
+
+	req->rate = best_rate;
+	return 0;
 }
 
 static int clk_programmable_set_parent(struct clk_hw *hw, u8 index)

drivers/clk/at91/clk-usb.c

···
 	return DIV_ROUND_CLOSEST(parent_rate, (usbdiv + 1));
 }
 
-static long at91sam9x5_clk_usb_determine_rate(struct clk_hw *hw,
-					      unsigned long rate,
-					      unsigned long min_rate,
-					      unsigned long max_rate,
-					      unsigned long *best_parent_rate,
-					      struct clk_hw **best_parent_hw)
+static int at91sam9x5_clk_usb_determine_rate(struct clk_hw *hw,
+					     struct clk_rate_request *req)
 {
 	struct clk *parent = NULL;
 	long best_rate = -EINVAL;
···
 		for (div = 1; div < SAM9X5_USB_MAX_DIV + 2; div++) {
 			unsigned long tmp_parent_rate;
 
-			tmp_parent_rate = rate * div;
+			tmp_parent_rate = req->rate * div;
 			tmp_parent_rate = __clk_round_rate(parent,
 							   tmp_parent_rate);
 			tmp_rate = DIV_ROUND_CLOSEST(tmp_parent_rate, div);
-			if (tmp_rate < rate)
-				tmp_diff = rate - tmp_rate;
+			if (tmp_rate < req->rate)
+				tmp_diff = req->rate - tmp_rate;
 			else
-				tmp_diff = tmp_rate - rate;
+				tmp_diff = tmp_rate - req->rate;
 
 			if (best_diff < 0 || best_diff > tmp_diff) {
 				best_rate = tmp_rate;
 				best_diff = tmp_diff;
-				*best_parent_rate = tmp_parent_rate;
-				*best_parent_hw = __clk_get_hw(parent);
+				req->best_parent_rate = tmp_parent_rate;
+				req->best_parent_hw = __clk_get_hw(parent);
 			}
 
-			if (!best_diff || tmp_rate < rate)
+			if (!best_diff || tmp_rate < req->rate)
 				break;
 		}
 
···
 			break;
 	}
 
-	return best_rate;
+	if (best_rate < 0)
+		return best_rate;
+
+	req->rate = best_rate;
+	return 0;
 }
 
 static int at91sam9x5_clk_usb_set_parent(struct clk_hw *hw, u8 index)

drivers/clk/bcm/clk-kona.c

···
 				rate ? rate : 1, *parent_rate, NULL);
 }
 
-static long kona_peri_clk_determine_rate(struct clk_hw *hw, unsigned long rate,
-		unsigned long min_rate,
-		unsigned long max_rate,
-		unsigned long *best_parent_rate, struct clk_hw **best_parent)
+static int kona_peri_clk_determine_rate(struct clk_hw *hw,
+					struct clk_rate_request *req)
 {
 	struct kona_clk *bcm_clk = to_kona_clk(hw);
 	struct clk *clk = hw->clk;
···
 	unsigned long best_delta;
 	unsigned long best_rate;
 	u32 parent_count;
+	long rate;
 	u32 which;
 
 	/*
···
 	 */
 	WARN_ON_ONCE(bcm_clk->init_data.flags & CLK_SET_RATE_NO_REPARENT);
 	parent_count = (u32)bcm_clk->init_data.num_parents;
-	if (parent_count < 2)
-		return kona_peri_clk_round_rate(hw, rate, best_parent_rate);
+	if (parent_count < 2) {
+		rate = kona_peri_clk_round_rate(hw, req->rate,
+						&req->best_parent_rate);
+		if (rate < 0)
+			return rate;
+
+		req->rate = rate;
+		return 0;
+	}
 
 	/* Unless we can do better, stick with current parent */
 	current_parent = clk_get_parent(clk);
 	parent_rate = __clk_get_rate(current_parent);
-	best_rate = kona_peri_clk_round_rate(hw, rate, &parent_rate);
-	best_delta = abs(best_rate - rate);
+	best_rate = kona_peri_clk_round_rate(hw, req->rate, &parent_rate);
+	best_delta = abs(best_rate - req->rate);
 
 	/* Check whether any other parent clock can produce a better result */
 	for (which = 0; which < parent_count; which++) {
···
 
 		/* We don't support CLK_SET_RATE_PARENT */
 		parent_rate = __clk_get_rate(parent);
-		other_rate = kona_peri_clk_round_rate(hw, rate, &parent_rate);
-		delta = abs(other_rate - rate);
+		other_rate = kona_peri_clk_round_rate(hw, req->rate,
+						      &parent_rate);
+		delta = abs(other_rate - req->rate);
 		if (delta < best_delta) {
 			best_delta = delta;
 			best_rate = other_rate;
-			*best_parent = __clk_get_hw(parent);
-			*best_parent_rate = parent_rate;
+			req->best_parent_hw = __clk_get_hw(parent);
+			req->best_parent_rate = parent_rate;
 		}
 	}
 
-	return best_rate;
+	req->rate = best_rate;
+	return 0;
 }
 
 static int kona_peri_clk_set_parent(struct clk_hw *hw, u8 index)

drivers/clk/clk-composite.c

···
 	return rate_ops->recalc_rate(rate_hw, parent_rate);
 }
 
-static long clk_composite_determine_rate(struct clk_hw *hw, unsigned long rate,
-					unsigned long min_rate,
-					unsigned long max_rate,
-					unsigned long *best_parent_rate,
-					struct clk_hw **best_parent_p)
+static int clk_composite_determine_rate(struct clk_hw *hw,
+					struct clk_rate_request *req)
 {
 	struct clk_composite *composite = to_clk_composite(hw);
 	const struct clk_ops *rate_ops = composite->rate_ops;
···
 	long tmp_rate, best_rate = 0;
 	unsigned long rate_diff;
 	unsigned long best_rate_diff = ULONG_MAX;
+	long rate;
 	int i;
 
 	if (rate_hw && rate_ops && rate_ops->determine_rate) {
 		__clk_hw_set_clk(rate_hw, hw);
-		return rate_ops->determine_rate(rate_hw, rate, min_rate,
-						max_rate,
-						best_parent_rate,
-						best_parent_p);
+		return rate_ops->determine_rate(rate_hw, req);
 	} else if (rate_hw && rate_ops && rate_ops->round_rate &&
 		   mux_hw && mux_ops && mux_ops->set_parent) {
-		*best_parent_p = NULL;
+		req->best_parent_hw = NULL;
 
 		if (__clk_get_flags(hw->clk) & CLK_SET_RATE_NO_REPARENT) {
 			parent = clk_get_parent(mux_hw->clk);
-			*best_parent_p = __clk_get_hw(parent);
-			*best_parent_rate = __clk_get_rate(parent);
+			req->best_parent_hw = __clk_get_hw(parent);
+			req->best_parent_rate = __clk_get_rate(parent);
 
-			return rate_ops->round_rate(rate_hw, rate,
-						    best_parent_rate);
+			rate = rate_ops->round_rate(rate_hw, req->rate,
+						    &req->best_parent_rate);
+			if (rate < 0)
+				return rate;
+
+			req->rate = rate;
+			return 0;
 		}
 
 		for (i = 0; i < __clk_get_num_parents(mux_hw->clk); i++) {
···
 
 			parent_rate = __clk_get_rate(parent);
 
-			tmp_rate = rate_ops->round_rate(rate_hw, rate,
+			tmp_rate = rate_ops->round_rate(rate_hw, req->rate,
 							&parent_rate);
 			if (tmp_rate < 0)
 				continue;
 
-			rate_diff = abs(rate - tmp_rate);
+			rate_diff = abs(req->rate - tmp_rate);
 
-			if (!rate_diff || !*best_parent_p
+			if (!rate_diff || !req->best_parent_hw
 				       || best_rate_diff > rate_diff) {
-				*best_parent_p = __clk_get_hw(parent);
-				*best_parent_rate = parent_rate;
+				req->best_parent_hw = __clk_get_hw(parent);
+				req->best_parent_rate = parent_rate;
 				best_rate_diff = rate_diff;
 				best_rate = tmp_rate;
 			}
 
 			if (!rate_diff)
-				return rate;
+				return 0;
 		}
 
-		return best_rate;
+		req->rate = best_rate;
+		return 0;
 	} else if (mux_hw && mux_ops && mux_ops->determine_rate) {
 		__clk_hw_set_clk(mux_hw, hw);
-		return mux_ops->determine_rate(mux_hw, rate, min_rate,
-					       max_rate, best_parent_rate,
-					       best_parent_p);
+		return mux_ops->determine_rate(mux_hw, req);
 	} else {
 		pr_err("clk: clk_composite_determine_rate function called, but no mux or rate callback set!\n");
+		req->rate = 0;
 		return 0;
 	}
 }

drivers/clk/clk.c

···
 	return now <= rate && now > best;
 }
 
-static long
-clk_mux_determine_rate_flags(struct clk_hw *hw, unsigned long rate,
-			     unsigned long min_rate,
-			     unsigned long max_rate,
-			     unsigned long *best_parent_rate,
-			     struct clk_hw **best_parent_p,
+static int
+clk_mux_determine_rate_flags(struct clk_hw *hw, struct clk_rate_request *req,
 			     unsigned long flags)
 {
 	struct clk_core *core = hw->core, *parent, *best_parent = NULL;
-	int i, num_parents;
-	unsigned long parent_rate, best = 0;
+	int i, num_parents, ret;
+	unsigned long best = 0;
+	struct clk_rate_request parent_req = *req;
 
 	/* if NO_REPARENT flag set, pass through to current parent */
 	if (core->flags & CLK_SET_RATE_NO_REPARENT) {
 		parent = core->parent;
-		if (core->flags & CLK_SET_RATE_PARENT)
-			best = __clk_determine_rate(parent ? parent->hw : NULL,
-						    rate, min_rate, max_rate);
-		else if (parent)
+		if (core->flags & CLK_SET_RATE_PARENT) {
+			ret = __clk_determine_rate(parent ? parent->hw : NULL,
+						   &parent_req);
+			if (ret)
+				return ret;
+
+			best = parent_req.rate;
+		} else if (parent) {
 			best = clk_core_get_rate_nolock(parent);
-		else
+		} else {
 			best = clk_core_get_rate_nolock(core);
+		}
+
 		goto out;
 	}
 
···
 		parent = clk_core_get_parent_by_index(core, i);
 		if (!parent)
 			continue;
-		if (core->flags & CLK_SET_RATE_PARENT)
-			parent_rate = __clk_determine_rate(parent->hw, rate,
-							   min_rate,
-							   max_rate);
-		else
-			parent_rate = clk_core_get_rate_nolock(parent);
-		if (mux_is_better_rate(rate, parent_rate, best, flags)) {
+
+		if (core->flags & CLK_SET_RATE_PARENT) {
+			parent_req = *req;
+			ret = __clk_determine_rate(parent->hw, &parent_req);
+			if (ret)
+				continue;
+		} else {
+			parent_req.rate = clk_core_get_rate_nolock(parent);
+		}
+
+		if (mux_is_better_rate(req->rate, parent_req.rate,
+				       best, flags)) {
 			best_parent = parent;
-			best = parent_rate;
+			best = parent_req.rate;
 		}
 	}
 
 out:
 	if (best_parent)
-		*best_parent_p = best_parent->hw;
-	*best_parent_rate = best;
+		req->best_parent_hw = best_parent->hw;
+	req->best_parent_rate = best;
+	req->rate = best;
 
-	return best;
+	return 0;
 }
 
 struct clk *__clk_lookup(const char *name)
···
  * directly as a determine_rate callback (e.g. for a mux), or from a more
  * complex clock that may combine a mux with other operations.
  */
-long __clk_mux_determine_rate(struct clk_hw *hw, unsigned long rate,
-			      unsigned long min_rate,
-			      unsigned long max_rate,
-			      unsigned long *best_parent_rate,
-			      struct clk_hw **best_parent_p)
+int __clk_mux_determine_rate(struct clk_hw *hw,
+			     struct clk_rate_request *req)
 {
-	return clk_mux_determine_rate_flags(hw, rate, min_rate, max_rate,
-					    best_parent_rate,
-					    best_parent_p, 0);
+	return clk_mux_determine_rate_flags(hw, req, 0);
 }
 EXPORT_SYMBOL_GPL(__clk_mux_determine_rate);
 
-long __clk_mux_determine_rate_closest(struct clk_hw *hw, unsigned long rate,
-			      unsigned long min_rate,
-			      unsigned long max_rate,
-			      unsigned long *best_parent_rate,
-			      struct clk_hw **best_parent_p)
+int __clk_mux_determine_rate_closest(struct clk_hw *hw,
+				     struct clk_rate_request *req)
 {
-	return clk_mux_determine_rate_flags(hw, rate, min_rate, max_rate,
-					    best_parent_rate,
-					    best_parent_p,
-					    CLK_MUX_ROUND_CLOSEST);
+	return clk_mux_determine_rate_flags(hw, req, CLK_MUX_ROUND_CLOSEST);
 }
 EXPORT_SYMBOL_GPL(__clk_mux_determine_rate_closest);
 
···
 }
 EXPORT_SYMBOL_GPL(clk_enable);
 
-static unsigned long clk_core_round_rate_nolock(struct clk_core *core,
-						unsigned long rate,
-						unsigned long min_rate,
-						unsigned long max_rate)
+static int clk_core_round_rate_nolock(struct clk_core *core,
+				      struct clk_rate_request *req)
 {
-	unsigned long parent_rate = 0;
 	struct clk_core *parent;
-	struct clk_hw *parent_hw;
+	long rate;
 
 	lockdep_assert_held(&prepare_lock);
 
···
 		return 0;
 
 	parent = core->parent;
-	if (parent)
-		parent_rate = parent->rate;
+	if (parent) {
+		req->best_parent_hw = parent->hw;
+		req->best_parent_rate = parent->rate;
+	} else {
+		req->best_parent_hw = NULL;
+		req->best_parent_rate = 0;
+	}
 
 	if (core->ops->determine_rate) {
-		parent_hw = parent ? parent->hw : NULL;
-		return core->ops->determine_rate(core->hw, rate,
-						min_rate, max_rate,
-						&parent_rate, &parent_hw);
-	} else if (core->ops->round_rate)
-		return core->ops->round_rate(core->hw, rate, &parent_rate);
-	else if (core->flags & CLK_SET_RATE_PARENT)
-		return clk_core_round_rate_nolock(core->parent, rate, min_rate,
-						  max_rate);
-	else
-		return core->rate;
+		return core->ops->determine_rate(core->hw, req);
+	} else if (core->ops->round_rate) {
+		rate = core->ops->round_rate(core->hw, req->rate,
+					     &req->best_parent_rate);
+		if (rate < 0)
+			return rate;
+
+		req->rate = rate;
+	} else if (core->flags & CLK_SET_RATE_PARENT) {
+		return clk_core_round_rate_nolock(parent, req);
+	} else {
+		req->rate = core->rate;
+	}
+
+	return 0;
 }
 
 /**
···
  *
  * Useful for clk_ops such as .set_rate and .determine_rate.
  */
-unsigned long __clk_determine_rate(struct clk_hw *hw,
-				   unsigned long rate,
-				   unsigned long min_rate,
-				   unsigned long max_rate)
+int __clk_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
 {
-	if (!hw)
+	if (!hw) {
+		req->rate = 0;
 		return 0;
+	}
 
-	return clk_core_round_rate_nolock(hw->core, rate, min_rate, max_rate);
+	return clk_core_round_rate_nolock(hw->core, req);
 }
 EXPORT_SYMBOL_GPL(__clk_determine_rate);
 
···
  */
 unsigned long __clk_round_rate(struct clk *clk, unsigned long rate)
 {
-	unsigned long min_rate;
-	unsigned long max_rate;
+	struct clk_rate_request req;
+	int ret;
 
 	if (!clk)
 		return 0;
 
-	clk_core_get_boundaries(clk->core, &min_rate, &max_rate);
+	clk_core_get_boundaries(clk->core, &req.min_rate, &req.max_rate);
+	req.rate = rate;
 
-	return clk_core_round_rate_nolock(clk->core, rate, min_rate, max_rate);
+	ret = clk_core_round_rate_nolock(clk->core, &req);
+	if (ret)
+		return 0;
+
+	return req.rate;
 }
 EXPORT_SYMBOL_GPL(__clk_round_rate);
 
···
 {
 	struct clk_core *top = core;
 	struct clk_core *old_parent, *parent;
-	struct clk_hw *parent_hw;
 	unsigned long best_parent_rate = 0;
 	unsigned long new_rate;
 	unsigned long min_rate;
···
 
 	/* find the closest rate and parent clk/rate */
 	if (core->ops->determine_rate) {
-		parent_hw = parent ? parent->hw : NULL;
-		ret = core->ops->determine_rate(core->hw, rate,
-					       min_rate,
-					       max_rate,
-					       &best_parent_rate,
-					       &parent_hw);
+		struct clk_rate_request req;
+
+		req.rate = rate;
+		req.min_rate = min_rate;
+		req.max_rate = max_rate;
+		if (parent) {
+			req.best_parent_hw = parent->hw;
+			req.best_parent_rate = parent->rate;
+		} else {
+			req.best_parent_hw = NULL;
+			req.best_parent_rate = 0;
+		}
+
+		ret = core->ops->determine_rate(core->hw, &req);
 		if (ret < 0)
 			return NULL;
 
-		new_rate = ret;
-		parent = parent_hw ? parent_hw->core : NULL;
+		best_parent_rate = req.best_parent_rate;
+		new_rate = req.rate;
+		parent = req.best_parent_hw ? req.best_parent_hw->core : NULL;
 	} else if (core->ops->round_rate) {
 		ret = core->ops->round_rate(core->hw, rate,
-					   &best_parent_rate);
+					    &best_parent_rate);
 		if (ret < 0)
 			return NULL;
 

drivers/clk/hisilicon/clk-hi3620.c

···
 	}
 }
 
-static long mmc_clk_determine_rate(struct clk_hw *hw, unsigned long rate,
-			      unsigned long min_rate,
-			      unsigned long max_rate,
-			      unsigned long *best_parent_rate,
-			      struct clk_hw **best_parent_p)
+static int mmc_clk_determine_rate(struct clk_hw *hw,
+				  struct clk_rate_request *req)
 {
 	struct clk_mmc *mclk = to_mmc(hw);
-	unsigned long best = 0;
 
-	if ((rate <= 13000000) && (mclk->id == HI3620_MMC_CIUCLK1)) {
-		rate = 13000000;
-		best = 26000000;
-	} else if (rate <= 26000000) {
-		rate = 25000000;
-		best = 180000000;
-	} else if (rate <= 52000000) {
-		rate = 50000000;
-		best = 360000000;
-	} else if (rate <= 100000000) {
-		rate = 100000000;
-		best = 720000000;
+	if ((req->rate <= 13000000) && (mclk->id == HI3620_MMC_CIUCLK1)) {
+		req->rate = 13000000;
+		req->best_parent_rate = 26000000;
+	} else if (req->rate <= 26000000) {
+		req->rate = 25000000;
+		req->best_parent_rate = 180000000;
+	} else if (req->rate <= 52000000) {
+		req->rate = 50000000;
+		req->best_parent_rate = 360000000;
+	} else if (req->rate <= 100000000) {
+		req->rate = 100000000;
+		req->best_parent_rate = 720000000;
 	} else {
 		/* max is 180M */
-		rate = 180000000;
-		best = 1440000000;
+		req->rate = 180000000;
+		req->best_parent_rate = 1440000000;
 	}
-	*best_parent_rate = best;
-	return rate;
+	return 0;
 }
 
 static u32 mmc_clk_delay(u32 val, u32 para, u32 off, u32 len)

drivers/clk/mmp/clk-mix.c

···
 	return ret;
 }
 
-static long mmp_clk_mix_determine_rate(struct clk_hw *hw, unsigned long rate,
-					unsigned long min_rate,
-					unsigned long max_rate,
-					unsigned long *best_parent_rate,
-					struct clk_hw **best_parent_clk)
+static int mmp_clk_mix_determine_rate(struct clk_hw *hw,
+				      struct clk_rate_request *req)
 {
 	struct mmp_clk_mix *mix = to_clk_mix(hw);
 	struct mmp_clk_mix_clk_table *item;
···
 	parent = NULL;
 	mix_rate_best = 0;
 	parent_rate_best = 0;
-	gap_best = rate;
+	gap_best = req->rate;
 	parent_best = NULL;
 
 	if (mix->table) {
···
 							item->parent_index);
 			parent_rate = __clk_get_rate(parent);
 			mix_rate = parent_rate / item->divisor;
-			gap = abs(mix_rate - rate);
+			gap = abs(mix_rate - req->rate);
 			if (parent_best == NULL || gap < gap_best) {
 				parent_best = parent;
 				parent_rate_best = parent_rate;
···
 			for (j = 0; j < div_val_max; j++) {
 				div = _get_div(mix, j);
 				mix_rate = parent_rate / div;
-				gap = abs(mix_rate - rate);
+				gap = abs(mix_rate - req->rate);
 				if (parent_best == NULL || gap < gap_best) {
 					parent_best = parent;
 					parent_rate_best = parent_rate;
···
 	}
 
 found:
-	*best_parent_rate = parent_rate_best;
-	*best_parent_clk = __clk_get_hw(parent_best);
+	req->best_parent_rate = parent_rate_best;
+	req->best_parent_hw = __clk_get_hw(parent_best);
+	req->rate = mix_rate_best;
 
-	return mix_rate_best;
+	return 0;
 }
 
 static int mmp_clk_mix_set_rate_and_parent(struct clk_hw *hw,

drivers/clk/qcom/clk-pll.c

···
 	return NULL;
 }
 
-static long
-clk_pll_determine_rate(struct clk_hw *hw, unsigned long rate,
-		       unsigned long min_rate, unsigned long max_rate,
-		       unsigned long *p_rate, struct clk_hw **p)
+static int
+clk_pll_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
 {
+	struct clk *parent = __clk_get_parent(hw->clk);
 	struct clk_pll *pll = to_clk_pll(hw);
 	const struct pll_freq_tbl *f;
 
-	f = find_freq(pll->freq_tbl, rate);
-	if (!f)
-		return clk_pll_recalc_rate(hw, *p_rate);
+	req->best_parent_hw = __clk_get_hw(parent);
+	req->best_parent_rate = __clk_get_rate(parent);
 
-	return f->freq;
+	f = find_freq(pll->freq_tbl, req->rate);
+	if (!f)
+		req->rate = clk_pll_recalc_rate(hw, req->best_parent_rate);
+	else
+		req->rate = f->freq;
+
+	return 0;
 }
 
 static int

drivers/clk/qcom/clk-rcg.c

···
 	return calc_rate(parent_rate, m, n, mode, pre_div);
 }
 
-static long _freq_tbl_determine_rate(struct clk_hw *hw,
-		const struct freq_tbl *f, unsigned long rate,
-		unsigned long min_rate, unsigned long max_rate,
-		unsigned long *p_rate, struct clk_hw **p_hw,
+static int _freq_tbl_determine_rate(struct clk_hw *hw, const struct freq_tbl *f,
+		struct clk_rate_request *req,
 		const struct parent_map *parent_map)
 {
-	unsigned long clk_flags;
+	unsigned long clk_flags, rate = req->rate;
 	struct clk *p;
 	int index;
 
···
 	} else {
 		rate =  __clk_get_rate(p);
 	}
-	*p_hw = __clk_get_hw(p);
-	*p_rate = rate;
+	req->best_parent_hw = __clk_get_hw(p);
+	req->best_parent_rate = rate;
+	req->rate = f->freq;
 
-	return f->freq;
+	return 0;
 }
 
-static long clk_rcg_determine_rate(struct clk_hw *hw, unsigned long rate,
-		unsigned long min_rate, unsigned long max_rate,
-		unsigned long *p_rate, struct clk_hw **p)
+static int clk_rcg_determine_rate(struct clk_hw *hw,
+				  struct clk_rate_request *req)
 {
 	struct clk_rcg *rcg = to_clk_rcg(hw);
 
-	return _freq_tbl_determine_rate(hw, rcg->freq_tbl, rate, min_rate,
-			max_rate, p_rate, p, rcg->s.parent_map);
+	return _freq_tbl_determine_rate(hw, rcg->freq_tbl, req,
+					rcg->s.parent_map);
 }
 
-static long clk_dyn_rcg_determine_rate(struct clk_hw *hw, unsigned long rate,
-		unsigned long min_rate, unsigned long max_rate,
-		unsigned long *p_rate, struct clk_hw **p)
+static int clk_dyn_rcg_determine_rate(struct clk_hw *hw,
+				      struct clk_rate_request *req)
 {
 	struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw);
 	u32 reg;
···
 	bank = reg_to_bank(rcg, reg);
 	s = &rcg->s[bank];
 
-	return _freq_tbl_determine_rate(hw, rcg->freq_tbl, rate, min_rate,
-			max_rate, p_rate, p, s->parent_map);
+	return _freq_tbl_determine_rate(hw, rcg->freq_tbl, req, s->parent_map);
 }
 
-static long clk_rcg_bypass_determine_rate(struct clk_hw *hw, unsigned long rate,
-		unsigned long min_rate, unsigned long max_rate,
-		unsigned long *p_rate, struct clk_hw **p_hw)
+static int clk_rcg_bypass_determine_rate(struct clk_hw *hw,
+					 struct clk_rate_request *req)
 {
 	struct clk_rcg *rcg = to_clk_rcg(hw);
 	const struct freq_tbl *f = rcg->freq_tbl;
···
 	int index = qcom_find_src_index(hw, rcg->s.parent_map, f->src);
 
 	p = clk_get_parent_by_index(hw->clk, index);
-	*p_hw = __clk_get_hw(p);
-	*p_rate = __clk_round_rate(p, rate);
+	req->best_parent_hw = __clk_get_hw(p);
+	req->best_parent_rate = __clk_round_rate(p, req->rate);
+	req->rate = req->best_parent_rate;
 
-	return *p_rate;
+	return 0;
 }
 
 static int __clk_rcg_set_rate(struct clk_rcg *rcg, const struct freq_tbl *f)

drivers/clk/qcom/clk-rcg2.c

···
 	return calc_rate(parent_rate, m, n, mode, hid_div);
 }
 
-static long _freq_tbl_determine_rate(struct clk_hw *hw,
-		const struct freq_tbl *f, unsigned long rate,
-		unsigned long *p_rate, struct clk_hw **p_hw)
+static int _freq_tbl_determine_rate(struct clk_hw *hw,
+		const struct freq_tbl *f, struct clk_rate_request *req)
 {
-	unsigned long clk_flags;
+	unsigned long clk_flags, rate = req->rate;
 	struct clk *p;
 	struct clk_rcg2 *rcg = to_clk_rcg2(hw);
 	int index;
···
 	} else {
 		rate =  __clk_get_rate(p);
 	}
-	*p_hw = __clk_get_hw(p);
-	*p_rate = rate;
+	req->best_parent_hw = __clk_get_hw(p);
+	req->best_parent_rate = rate;
+	req->rate = f->freq;
 
-	return f->freq;
+	return 0;
 }
 
-static long clk_rcg2_determine_rate(struct clk_hw *hw, unsigned long rate,
-		unsigned long min_rate, unsigned long max_rate,
-		unsigned long *p_rate, struct clk_hw **p)
+static int clk_rcg2_determine_rate(struct clk_hw *hw,
+				   struct clk_rate_request *req)
 {
 	struct clk_rcg2 *rcg = to_clk_rcg2(hw);
 
-	return _freq_tbl_determine_rate(hw, rcg->freq_tbl, rate, p_rate, p);
+	return _freq_tbl_determine_rate(hw, rcg->freq_tbl, req);
 }
 
 static int clk_rcg2_configure(struct clk_rcg2 *rcg, const struct freq_tbl *f)
···
 	return clk_edp_pixel_set_rate(hw, rate, parent_rate);
 }
 
-static long clk_edp_pixel_determine_rate(struct clk_hw *hw, unsigned long rate,
-				 unsigned long min_rate,
-				 unsigned long max_rate,
-				 unsigned long *p_rate, struct clk_hw **p)
+static int clk_edp_pixel_determine_rate(struct clk_hw *hw,
+					struct clk_rate_request *req)
 {
 	struct clk_rcg2 *rcg = to_clk_rcg2(hw);
 	const struct freq_tbl *f = rcg->freq_tbl;
 	const struct frac_entry *frac;
 	int delta = 100000;
-	s64 src_rate = *p_rate;
 	s64 request;
 	u32 mask = BIT(rcg->hid_width) - 1;
 	u32 hid_div;
 	int index = qcom_find_src_index(hw, rcg->parent_map, f->src);
+	struct clk *p = clk_get_parent_by_index(hw->clk, index);
 
 	/* Force the correct parent */
-	*p = __clk_get_hw(clk_get_parent_by_index(hw->clk, index));
+	req->best_parent_hw = __clk_get_hw(p);
+	req->best_parent_rate = __clk_get_rate(p);
 
-	if (src_rate == 810000000)
+	if (req->best_parent_rate == 810000000)
 		frac = frac_table_810m;
 	else
 		frac = frac_table_675m;
 
 	for (; frac->num; frac++) {
-		request = rate;
+		request = req->rate;
 		request *= frac->den;
 		request = div_s64(request, frac->num);
-		if ((src_rate < (request - delta)) ||
-		    (src_rate > (request + delta)))
+		if ((req->best_parent_rate < (request - delta)) ||
+		    (req->best_parent_rate > (request + delta)))
 			continue;
 
 		regmap_read(rcg->clkr.regmap, rcg->cmd_rcgr + CFG_REG,
···
 		hid_div >>= CFG_SRC_DIV_SHIFT;
 		hid_div &= mask;
 
-		return calc_rate(src_rate, frac->num, frac->den, !!frac->den,
-				 hid_div);
+		req->rate = calc_rate(req->best_parent_rate,
+				      frac->num, frac->den,
+				      !!frac->den, hid_div);
+		return 0;
 	}
 
 	return -EINVAL;
···
 };
 EXPORT_SYMBOL_GPL(clk_edp_pixel_ops);
 
-static long clk_byte_determine_rate(struct clk_hw *hw, unsigned long rate,
-			 unsigned long min_rate, unsigned long max_rate,
-			 unsigned long *p_rate, struct clk_hw **p_hw)
+static int clk_byte_determine_rate(struct clk_hw *hw,
+				   struct clk_rate_request *req)
 {
 	struct clk_rcg2 *rcg = to_clk_rcg2(hw);
 	const struct freq_tbl *f = rcg->freq_tbl;
···
 	u32 mask = BIT(rcg->hid_width) - 1;
 	struct clk *p;
 
-	if (rate == 0)
+	if (req->rate == 0)
 		return -EINVAL;
 
 	p = clk_get_parent_by_index(hw->clk, index);
-	*p_hw = __clk_get_hw(p);
-	*p_rate = parent_rate = __clk_round_rate(p, rate);
+	req->best_parent_hw = __clk_get_hw(p);
+	req->best_parent_rate = parent_rate = __clk_round_rate(p, req->rate);
 
-	div = DIV_ROUND_UP((2 * parent_rate), rate) - 1;
+	div = DIV_ROUND_UP((2 * parent_rate), req->rate) - 1;
 	div = min_t(u32, div, mask);
 
-	return calc_rate(parent_rate, 0, 0, 0, div);
+	req->rate = calc_rate(parent_rate, 0, 0, 0, div);
+
+	return 0;
 }
 
 static int clk_byte_set_rate(struct clk_hw *hw, unsigned long rate,
···
 	{ }
 };
 
-static long clk_pixel_determine_rate(struct clk_hw *hw, unsigned long rate,
-				 unsigned long min_rate,
-				 unsigned long max_rate,
-				 unsigned long *p_rate, struct clk_hw **p)
+static int clk_pixel_determine_rate(struct clk_hw *hw,
+				    struct clk_rate_request *req)
 {
 	struct clk_rcg2 *rcg = to_clk_rcg2(hw);
 	unsigned long request, src_rate;
···
 	int index = qcom_find_src_index(hw, rcg->parent_map, f->src);
 	struct clk *parent = clk_get_parent_by_index(hw->clk, index);
 
-	*p = __clk_get_hw(parent);
+	req->best_parent_hw = __clk_get_hw(parent);
 
 	for (; frac->num; frac++) {
-		request = (rate * frac->den) / frac->num;
+		request = (req->rate * frac->den) / frac->num;
 
 		src_rate = __clk_round_rate(parent, request);
 		if ((src_rate < (request - delta)) ||
 			(src_rate > (request + delta)))
 			continue;
 
-		*p_rate = src_rate;
-		return (src_rate * frac->num) / frac->den;
+		req->best_parent_rate = src_rate;
+		req->rate = (src_rate * frac->num) / frac->den;
+		return 0;
 	}
 
 	return -EINVAL;

drivers/clk/sunxi/clk-factors.c

···
 	return rate;
 }
 
-static long clk_factors_determine_rate(struct clk_hw *hw, unsigned long rate,
-				       unsigned long min_rate,
-				       unsigned long max_rate,
-				       unsigned long *best_parent_rate,
-				       struct clk_hw **best_parent_p)
+static int clk_factors_determine_rate(struct clk_hw *hw,
+				      struct clk_rate_request *req)
 {
 	struct clk *clk = hw->clk, *parent, *best_parent = NULL;
 	int i, num_parents;
···
 		if (!parent)
 			continue;
 		if (__clk_get_flags(clk) & CLK_SET_RATE_PARENT)
-			parent_rate = __clk_round_rate(parent, rate);
+			parent_rate = __clk_round_rate(parent, req->rate);
 		else
 			parent_rate = __clk_get_rate(parent);
 
-		child_rate = clk_factors_round_rate(hw, rate, &parent_rate);
+		child_rate = clk_factors_round_rate(hw, req->rate,
+						    &parent_rate);
 
-		if (child_rate <= rate && child_rate > best_child_rate) {
+		if (child_rate <= req->rate && child_rate > best_child_rate) {
 			best_parent = parent;
 			best = parent_rate;
 			best_child_rate = child_rate;
···
 	}
 
 	if (best_parent)
-		*best_parent_p = __clk_get_hw(best_parent);
-	*best_parent_rate = best;
+		req->best_parent_hw = __clk_get_hw(best_parent);
+	req->best_parent_rate = best;
+	req->rate = best_child_rate;
 
-	return best_child_rate;
+	return 0;
 }
 
 static int clk_factors_set_rate(struct clk_hw *hw, unsigned long rate,

drivers/clk/sunxi/clk-sun6i-ar100.c

···
 	return (parent_rate >> shift) / (div + 1);
 }
 
-static long ar100_determine_rate(struct clk_hw *hw, unsigned long rate,
-				 unsigned long min_rate,
-				 unsigned long max_rate,
-				 unsigned long *best_parent_rate,
-				 struct clk_hw **best_parent_clk)
+static int ar100_determine_rate(struct clk_hw *hw,
+				struct clk_rate_request *req)
 {
 	int nparents = __clk_get_num_parents(hw->clk);
 	long best_rate = -EINVAL;
 	int i;
 
-	*best_parent_clk = NULL;
+	req->best_parent_hw = NULL;
 
 	for (i = 0; i < nparents; i++) {
 		unsigned long parent_rate;
···
 
 		parent = clk_get_parent_by_index(hw->clk, i);
 		parent_rate = __clk_get_rate(parent);
-		div = DIV_ROUND_UP(parent_rate, rate);
+		div = DIV_ROUND_UP(parent_rate, req->rate);
 
 		/*
 		 * The AR100 clk contains 2 divisors:
···
 			continue;
 
 		tmp_rate = (parent_rate >> shift) / div;
-		if (!*best_parent_clk || tmp_rate > best_rate) {
-			*best_parent_clk = __clk_get_hw(parent);
-			*best_parent_rate = parent_rate;
+		if (!req->best_parent_hw || tmp_rate > best_rate) {
+			req->best_parent_hw = __clk_get_hw(parent);
+			req->best_parent_rate = parent_rate;
 			best_rate = tmp_rate;
 		}
 	}
 
-	return best_rate;
+	req->rate = best_rate;
+
+	return 0;
 }
 
 static int ar100_set_parent(struct clk_hw *hw, u8 index)

drivers/clk/sunxi/clk-sunxi.c

···
 	return (parent_rate / calcm) >> calcp;
 }
 
-static long sun6i_ahb1_clk_determine_rate(struct clk_hw *hw, unsigned long rate,
-					  unsigned long min_rate,
-					  unsigned long max_rate,
-					  unsigned long *best_parent_rate,
-					  struct clk_hw **best_parent_clk)
+static int sun6i_ahb1_clk_determine_rate(struct clk_hw *hw,
+					 struct clk_rate_request *req)
 {
 	struct clk *clk = hw->clk, *parent, *best_parent = NULL;
 	int i, num_parents;
···
 		if (!parent)
 			continue;
 		if (__clk_get_flags(clk) & CLK_SET_RATE_PARENT)
-			parent_rate = __clk_round_rate(parent, rate);
+			parent_rate = __clk_round_rate(parent, req->rate);
 		else
 			parent_rate = __clk_get_rate(parent);
 
-		child_rate = sun6i_ahb1_clk_round(rate, NULL, NULL, i,
+		child_rate = sun6i_ahb1_clk_round(req->rate, NULL, NULL, i,
 						  parent_rate);
 
-		if (child_rate <= rate && child_rate > best_child_rate) {
+		if (child_rate <= req->rate && child_rate > best_child_rate) {
 			best_parent = parent;
 			best = parent_rate;
 			best_child_rate = child_rate;
···
 	}
 
 	if (best_parent)
-		*best_parent_clk = __clk_get_hw(best_parent);
-	*best_parent_rate = best;
+		req->best_parent_hw = __clk_get_hw(best_parent);
+	req->best_parent_rate = best;
+	req->rate = best_child_rate;
 
-	return best_child_rate;
+	return 0;
 }
 
 static int sun6i_ahb1_clk_set_rate(struct clk_hw *hw, unsigned long rate,

drivers/clk/tegra/clk-emc.c

···
  * safer since things have EMC rate floors. Also don't touch parent_rate
  * since we don't want the CCF to play with our parent clocks.
  */
-static long emc_determine_rate(struct clk_hw *hw, unsigned long rate,
-			       unsigned long min_rate,
-			       unsigned long max_rate,
-			       unsigned long *best_parent_rate,
-			       struct clk_hw **best_parent_hw)
+static int emc_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
 {
 	struct tegra_clk_emc *tegra;
 	u8 ram_code = tegra_read_ram_code();
···
 
 		timing = tegra->timings + i;
 
-		if (timing->rate > max_rate) {
+		if (timing->rate > req->max_rate) {
 			i = min(i, 1);
-			return tegra->timings[i - 1].rate;
+			req->rate = tegra->timings[i - 1].rate;
+			return 0;
 		}
 
-		if (timing->rate < min_rate)
+		if (timing->rate < req->min_rate)
 			continue;
 
-		if (timing->rate >= rate)
-			return timing->rate;
+		if (timing->rate >= req->rate) {
+			req->rate = timing->rate;
+			return 0;
+		}
 	}
 
-	if (timing)
-		return timing->rate;
+	if (timing) {
+		req->rate = timing->rate;
+		return 0;
+	}
 
-	return __clk_get_rate(hw->clk);
+	req->rate = __clk_get_rate(hw->clk);
+	return 0;
 }
 
 static u8 emc_get_parent(struct clk_hw *hw)

include/linux/clk-provider.h

···
 struct dentry;
 
 /**
+ * struct clk_rate_request - Structure encoding the clk constraints that
+ * a clock user might require.
+ *
+ * @rate:		Requested clock rate. This field will be adjusted by
+ *			clock drivers according to hardware capabilities.
+ * @min_rate:		Minimum rate imposed by clk users.
+ * @max_rate:		Maximum rate a imposed by clk users.
+ * @best_parent_rate:	The best parent rate a parent can provide to fulfill the
+ *			requested constraints.
+ * @best_parent_hw:	The most appropriate parent clock that fulfills the
+ *			requested constraints.
+ *
+ */
+struct clk_rate_request {
+	unsigned long rate;
+	unsigned long min_rate;
+	unsigned long max_rate;
+	unsigned long best_parent_rate;
+	struct clk_hw *best_parent_hw;
+};
+
+/**
  * struct clk_ops -  Callback operations for hardware clocks; these are to
  * be provided by the clock implementation, and will be called by drivers
  * through the clk_* api.
···
 					unsigned long parent_rate);
 	long		(*round_rate)(struct clk_hw *hw, unsigned long rate,
 					unsigned long *parent_rate);
-	long		(*determine_rate)(struct clk_hw *hw,
-					  unsigned long rate,
-					  unsigned long min_rate,
-					  unsigned long max_rate,
-					  unsigned long *best_parent_rate,
-					  struct clk_hw **best_parent_hw);
+	int		(*determine_rate)(struct clk_hw *hw,
+					  struct clk_rate_request *req);
 	int		(*set_parent)(struct clk_hw *hw, u8 index);
 	u8		(*get_parent)(struct clk_hw *hw);
 	int		(*set_rate)(struct clk_hw *hw, unsigned long rate,
···
 bool __clk_is_prepared(struct clk *clk);
 bool __clk_is_enabled(struct clk *clk);
 struct clk *__clk_lookup(const char *name);
-long __clk_mux_determine_rate(struct clk_hw *hw, unsigned long rate,
-			      unsigned long min_rate,
-			      unsigned long max_rate,
-			      unsigned long *best_parent_rate,
-			      struct clk_hw **best_parent_p);
-unsigned long __clk_determine_rate(struct clk_hw *core,
-				   unsigned long rate,
-				   unsigned long min_rate,
-				   unsigned long max_rate);
-long __clk_mux_determine_rate_closest(struct clk_hw *hw, unsigned long rate,
-			      unsigned long min_rate,
-			      unsigned long max_rate,
-			      unsigned long *best_parent_rate,
-			      struct clk_hw **best_parent_p);
+int __clk_mux_determine_rate(struct clk_hw *hw,
+			     struct clk_rate_request *req);
+int __clk_determine_rate(struct clk_hw *core, struct clk_rate_request *req);
+int __clk_mux_determine_rate_closest(struct clk_hw *hw,
+				     struct clk_rate_request *req);
 void clk_hw_reparent(struct clk_hw *hw, struct clk_hw *new_parent);
 
 static inline void __clk_hw_set_clk(struct clk_hw *dst, struct clk_hw *src)

include/linux/clk/ti.h

···
 					   unsigned long rate,
 					   unsigned long parent_rate,
 					   u8 index);
-long omap3_noncore_dpll_determine_rate(struct clk_hw *hw,
-				       unsigned long rate,
-				       unsigned long min_rate,
-				       unsigned long max_rate,
-				       unsigned long *best_parent_rate,
-				       struct clk_hw **best_parent_clk);
+int omap3_noncore_dpll_determine_rate(struct clk_hw *hw,
+				      struct clk_rate_request *req);
 unsigned long omap4_dpll_regm4xen_recalc(struct clk_hw *hw,
 					 unsigned long parent_rate);
 long omap4_dpll_regm4xen_round_rate(struct clk_hw *hw,
 				    unsigned long target_rate,
 				    unsigned long *parent_rate);
-long omap4_dpll_regm4xen_determine_rate(struct clk_hw *hw,
-					unsigned long rate,
-					unsigned long min_rate,
-					unsigned long max_rate,
-					unsigned long *best_parent_rate,
-					struct clk_hw **best_parent_clk);
+int omap4_dpll_regm4xen_determine_rate(struct clk_hw *hw,
+				       struct clk_rate_request *req);
 u8 omap2_init_dpll_parent(struct clk_hw *hw);
 unsigned long omap3_dpll_recalc(struct clk_hw *hw, unsigned long parent_rate);
 long omap2_dpll_round_rate(struct clk_hw *hw, unsigned long target_rate,