clk: vc5: Split clock input mux and predivider

Split the VC5 clock input mux and the predivider to more accurately
model the hardware and fix the previously incorrect assumption that
both the OUT_SEL_I2CB and the PLL are fed from the predivider.

It is in fact the clock input mux output which is directly feeding
the clock into the OUT_SEL_I2CB output, while the clock input mux
output first passes through the predivider before it is fed into
the PLL.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Alexey Firago <alexey_firago@mentor.com>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: linux-renesas-soc@vger.kernel.org
Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
on Salvator-XS with the display LVDS output.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

drivers/clk/clk-versaclock5.c

@@ -157,6 +157,7 @@ struct vc5_driver_data {
 	struct clk		*pin_clkin;
 	unsigned char		clk_mux_ins;
 	struct clk_hw		clk_mux;
+	struct clk_hw		clk_pfd;
 	struct vc5_hw_data	clk_pll;
 	struct vc5_hw_data	clk_fod[VC5_MAX_FOD_NUM];
 	struct vc5_hw_data	clk_out[VC5_MAX_CLK_OUT_NUM];
@@ -166,6 +167,10 @@ static const char * const vc5_mux_names[] = {
 	"mux"
 };
 
+static const char * const vc5_pfd_names[] = {
+	"pfd"
+};
+
 static const char * const vc5_pll_names[] = {
 	"pll"
 };
@@ -254,11 +259,16 @@ static int vc5_mux_set_parent(struct clk_hw *hw, u8 index)
 	return regmap_update_bits(vc5->regmap, VC5_PRIM_SRC_SHDN, mask, src);
 }
 
-static unsigned long vc5_mux_recalc_rate(struct clk_hw *hw,
+static const struct clk_ops vc5_mux_ops = {
+	.set_parent	= vc5_mux_set_parent,
+	.get_parent	= vc5_mux_get_parent,
+};
+
+static unsigned long vc5_pfd_recalc_rate(struct clk_hw *hw,
 					 unsigned long parent_rate)
 {
 	struct vc5_driver_data *vc5 =
-		container_of(hw, struct vc5_driver_data, clk_mux);
+		container_of(hw, struct vc5_driver_data, clk_pfd);
 	unsigned int prediv, div;
 
 	regmap_read(vc5->regmap, VC5_VCO_CTRL_AND_PREDIV, &prediv);
@@ -276,7 +286,7 @@ static unsigned long vc5_mux_recalc_rate(struct clk_hw *hw,
 		return parent_rate / VC5_REF_DIVIDER_REF_DIV(div);
 }
 
-static long vc5_mux_round_rate(struct clk_hw *hw, unsigned long rate,
+static long vc5_pfd_round_rate(struct clk_hw *hw, unsigned long rate,
 			       unsigned long *parent_rate)
 {
 	unsigned long idiv;
@@ -296,11 +306,11 @@ static long vc5_mux_round_rate(struct clk_hw *hw, unsigned long rate,
 	return *parent_rate / idiv;
 }
 
-static int vc5_mux_set_rate(struct clk_hw *hw, unsigned long rate,
+static int vc5_pfd_set_rate(struct clk_hw *hw, unsigned long rate,
 			    unsigned long parent_rate)
 {
 	struct vc5_driver_data *vc5 =
-		container_of(hw, struct vc5_driver_data, clk_mux);
+		container_of(hw, struct vc5_driver_data, clk_pfd);
 	unsigned long idiv;
 	u8 div;
 
@@ -328,12 +338,10 @@ static int vc5_mux_set_rate(struct clk_hw *hw, unsigned long rate,
 	return 0;
 }
 
-static const struct clk_ops vc5_mux_ops = {
-	.set_parent	= vc5_mux_set_parent,
-	.get_parent	= vc5_mux_get_parent,
-	.recalc_rate	= vc5_mux_recalc_rate,
-	.round_rate	= vc5_mux_round_rate,
-	.set_rate	= vc5_mux_set_rate,
+static const struct clk_ops vc5_pfd_ops = {
+	.recalc_rate	= vc5_pfd_recalc_rate,
+	.round_rate	= vc5_pfd_round_rate,
+	.set_rate	= vc5_pfd_set_rate,
 };
 
 /*
@@ -698,12 +706,26 @@ static int vc5_probe(struct i2c_client *client,
 		goto err_clk;
 	}
 
+	/* Register PFD */
+	memset(&init, 0, sizeof(init));
+	init.name = vc5_pfd_names[0];
+	init.ops = &vc5_pfd_ops;
+	init.flags = CLK_SET_RATE_PARENT;
+	init.parent_names = vc5_mux_names;
+	init.num_parents = 1;
+	vc5->clk_pfd.init = &init;
+	ret = devm_clk_hw_register(&client->dev, &vc5->clk_pfd);
+	if (ret) {
+		dev_err(&client->dev, "unable to register %s\n", init.name);
+		goto err_clk;
+	}
+
 	/* Register PLL */
 	memset(&init, 0, sizeof(init));
 	init.name = vc5_pll_names[0];
 	init.ops = &vc5_pll_ops;
 	init.flags = CLK_SET_RATE_PARENT;
-	init.parent_names = vc5_mux_names;
+	init.parent_names = vc5_pfd_names;
 	init.num_parents = 1;
 	vc5->clk_pll.num = 0;
 	vc5->clk_pll.vc5 = vc5;