clk: bcm: rpi: Use CCF boundaries instead of rolling our own

The raspberrypi firmware clock driver has a min_rate / max_rate clamping by
storing the info it needs in a private structure.

However, the CCF already provides such a facility, so we can switch to it
to remove the boilerplate.

Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Tested-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/d4c53dab6de5d5f70743d9c139d0117589530e62.1592210452.git-series.maxime@cerno.tech
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

drivers/clk/bcm/clk-raspberrypi.c

@@ -36,9 +36,6 @@ struct raspberrypi_clk {
 	struct rpi_firmware *firmware;
 	struct platform_device *cpufreq;
 
-	unsigned long min_rate;
-	unsigned long max_rate;
-
 	struct clk_hw pllb;
 };
 
@@ -142,13 +139,11 @@ static int raspberrypi_fw_pll_set_rate(struct clk_hw *hw, unsigned long rate,
 static int raspberrypi_pll_determine_rate(struct clk_hw *hw,
 					  struct clk_rate_request *req)
 {
-	struct raspberrypi_clk *rpi = container_of(hw, struct raspberrypi_clk,
-						   pllb);
 	u64 div, final_rate;
 	u32 ndiv, fdiv;
 
 	/* We can't use req->rate directly as it would overflow */
-	final_rate = clamp(req->rate, rpi->min_rate, rpi->max_rate);
+	final_rate = clamp(req->rate, req->min_rate, req->max_rate);
 
 	div = (u64)final_rate << A2W_PLL_FRAC_BITS;
 	do_div(div, req->best_parent_rate);
@@ -215,12 +210,15 @@ static int raspberrypi_register_pllb(struct raspberrypi_clk *rpi)
 	dev_info(rpi->dev, "CPU frequency range: min %u, max %u\n",
 		 min_rate, max_rate);
 
-	rpi->min_rate = min_rate * RPI_FIRMWARE_PLLB_ARM_DIV_RATE;
-	rpi->max_rate = max_rate * RPI_FIRMWARE_PLLB_ARM_DIV_RATE;
-
 	rpi->pllb.init = &init;
 
-	return devm_clk_hw_register(rpi->dev, &rpi->pllb);
+	ret = devm_clk_hw_register(rpi->dev, &rpi->pllb);
+	if (!ret)
+		clk_hw_set_rate_range(&rpi->pllb,
+				      min_rate * RPI_FIRMWARE_PLLB_ARM_DIV_RATE,
+				      max_rate * RPI_FIRMWARE_PLLB_ARM_DIV_RATE);
+
+	return ret;
 }
 
 static struct clk_fixed_factor raspberrypi_clk_pllb_arm = {