phy: ti: j721e-wiz: Enable reference clock output in cmn_refclk_<p/m>

cmn_refclk_<p/m> lines in Torrent SERDES is used for connecting external
reference clock. cmn_refclk_<p/m> can also be configured to output the
reference clock. In order to drive the refclk out from the SERDES
(Cadence Torrent), PHY_EN_REFCLK should be set in SERDES_RST of WIZ.
Model PHY_EN_REFCLK as a clock, so that platforms like AM642 EVM can
enable it.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>

drivers/phy/ti/phy-j721e-wiz.c

@@ -66,6 +66,7 @@ enum wiz_clock_input {
 
 static const struct reg_field por_en = REG_FIELD(WIZ_SERDES_CTRL, 31, 31);
 static const struct reg_field phy_reset_n = REG_FIELD(WIZ_SERDES_RST, 31, 31);
+static const struct reg_field phy_en_refclk = REG_FIELD(WIZ_SERDES_RST, 30, 30);
 static const struct reg_field pll1_refclk_mux_sel =
 					REG_FIELD(WIZ_SERDES_RST, 29, 29);
 static const struct reg_field pll0_refclk_mux_sel =
@@ -86,6 +87,7 @@ static const char * const output_clk_names[] = {
 	[TI_WIZ_PLL0_REFCLK] = "pll0-refclk",
 	[TI_WIZ_PLL1_REFCLK] = "pll1-refclk",
 	[TI_WIZ_REFCLK_DIG] = "refclk-dig",
+	[TI_WIZ_PHY_EN_REFCLK] = "phy-en-refclk",
 };
 
 static const struct reg_field p_enable[WIZ_MAX_LANES] = {
@@ -158,6 +160,14 @@ struct wiz_clk_div_sel {
 	const char		*node_name;
 };
 
+struct wiz_phy_en_refclk {
+	struct clk_hw		hw;
+	struct regmap_field	*phy_en_refclk;
+	struct clk_init_data	clk_data;
+};
+
+#define to_wiz_phy_en_refclk(_hw) container_of(_hw, struct wiz_phy_en_refclk, hw)
+
 static const struct wiz_clk_mux_sel clk_mux_sel_16g[] = {
 	{
 		/*
@@ -237,6 +247,7 @@ struct wiz {
 	unsigned int		clk_div_sel_num;
 	struct regmap_field	*por_en;
 	struct regmap_field	*phy_reset_n;
+	struct regmap_field	*phy_en_refclk;
 	struct regmap_field	*p_enable[WIZ_MAX_LANES];
 	struct regmap_field	*p_align[WIZ_MAX_LANES];
 	struct regmap_field	*p_raw_auto_start[WIZ_MAX_LANES];
@@ -469,6 +480,76 @@ static int wiz_regfield_init(struct wiz *wiz)
 		return PTR_ERR(wiz->typec_ln10_swap);
 	}
 
+	wiz->phy_en_refclk = devm_regmap_field_alloc(dev, regmap, phy_en_refclk);
+	if (IS_ERR(wiz->phy_en_refclk)) {
+		dev_err(dev, "PHY_EN_REFCLK reg field init failed\n");
+		return PTR_ERR(wiz->phy_en_refclk);
+	}
+
+	return 0;
+}
+
+static int wiz_phy_en_refclk_enable(struct clk_hw *hw)
+{
+	struct wiz_phy_en_refclk *wiz_phy_en_refclk = to_wiz_phy_en_refclk(hw);
+	struct regmap_field *phy_en_refclk = wiz_phy_en_refclk->phy_en_refclk;
+
+	regmap_field_write(phy_en_refclk, 1);
+
+	return 0;
+}
+
+static void wiz_phy_en_refclk_disable(struct clk_hw *hw)
+{
+	struct wiz_phy_en_refclk *wiz_phy_en_refclk = to_wiz_phy_en_refclk(hw);
+	struct regmap_field *phy_en_refclk = wiz_phy_en_refclk->phy_en_refclk;
+
+	regmap_field_write(phy_en_refclk, 0);
+}
+
+static int wiz_phy_en_refclk_is_enabled(struct clk_hw *hw)
+{
+	struct wiz_phy_en_refclk *wiz_phy_en_refclk = to_wiz_phy_en_refclk(hw);
+	struct regmap_field *phy_en_refclk = wiz_phy_en_refclk->phy_en_refclk;
+	int val;
+
+	regmap_field_read(phy_en_refclk, &val);
+
+	return !!val;
+}
+
+static const struct clk_ops wiz_phy_en_refclk_ops = {
+	.enable = wiz_phy_en_refclk_enable,
+	.disable = wiz_phy_en_refclk_disable,
+	.is_enabled = wiz_phy_en_refclk_is_enabled,
+};
+
+static int wiz_phy_en_refclk_register(struct wiz *wiz)
+{
+	struct wiz_phy_en_refclk *wiz_phy_en_refclk;
+	struct device *dev = wiz->dev;
+	struct clk_init_data *init;
+	struct clk *clk;
+
+	wiz_phy_en_refclk = devm_kzalloc(dev, sizeof(*wiz_phy_en_refclk), GFP_KERNEL);
+	if (!wiz_phy_en_refclk)
+		return -ENOMEM;
+
+	init = &wiz_phy_en_refclk->clk_data;
+
+	init->ops = &wiz_phy_en_refclk_ops;
+	init->flags = 0;
+	init->name = output_clk_names[TI_WIZ_PHY_EN_REFCLK];
+
+	wiz_phy_en_refclk->phy_en_refclk = wiz->phy_en_refclk;
+	wiz_phy_en_refclk->hw.init = init;
+
+	clk = devm_clk_register(dev, &wiz_phy_en_refclk->hw);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	wiz->output_clks[TI_WIZ_PHY_EN_REFCLK] = clk;
+
 	return 0;
 }
 
@@ -724,6 +805,8 @@ static void wiz_clock_cleanup(struct wiz *wiz, struct device_node *node)
 		of_clk_del_provider(clk_node);
 		of_node_put(clk_node);
 	}
+
+	of_clk_del_provider(wiz->dev->of_node);
 }
 
 static int wiz_clock_register(struct wiz *wiz)
@@ -747,6 +830,12 @@ static int wiz_clock_register(struct wiz *wiz)
 		}
 	}
 
+	ret = wiz_phy_en_refclk_register(wiz);
+	if (ret) {
+		dev_err(dev, "Failed to add phy-en-refclk\n");
+		return ret;
+	}
+
 	wiz->clk_data.clks = wiz->output_clks;
 	wiz->clk_data.clk_num = WIZ_MAX_OUTPUT_CLOCKS;
 	ret = of_clk_add_provider(node, of_clk_src_onecell_get, &wiz->clk_data);