clk: meson: add sclk-ws driver

This is yet another simple but odd driver for the audio block of the g12a
and sm1 SoC families.

For TDMOUT's sclk to be properly inverted, bit 29 of
AUDIO_CLK_TDMOUT_x_CTRL should be the inverse of bit 28.
IOW bit28 == !bit29 at all times

This setting is automatically applied on axg and the manual setting was
added on g12a.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20200729154359.1983085-2-jbrunet@baylibre.com

drivers/clk/meson/clk-phase.c

@@ -125,6 +125,62 @@ const struct clk_ops meson_clk_triphase_ops = {
 };
 EXPORT_SYMBOL_GPL(meson_clk_triphase_ops);
 
+/*
+ * This is a special clock for the audio controller.
+ * This drive a bit clock inverter for which the
+ * opposite value of the inverter bit needs to be manually
+ * set into another bit
+ */
+static inline struct meson_sclk_ws_inv_data *
+meson_sclk_ws_inv_data(struct clk_regmap *clk)
+{
+	return (struct meson_sclk_ws_inv_data *)clk->data;
+}
+
+static int meson_sclk_ws_inv_sync(struct clk_hw *hw)
+{
+	struct clk_regmap *clk = to_clk_regmap(hw);
+	struct meson_sclk_ws_inv_data *tph = meson_sclk_ws_inv_data(clk);
+	unsigned int val;
+
+	/* Get phase and sync the inverted value to ws */
+	val = meson_parm_read(clk->map, &tph->ph);
+	meson_parm_write(clk->map, &tph->ws, val ? 0 : 1);
+
+	return 0;
+}
+
+static int meson_sclk_ws_inv_get_phase(struct clk_hw *hw)
+{
+	struct clk_regmap *clk = to_clk_regmap(hw);
+	struct meson_sclk_ws_inv_data *tph = meson_sclk_ws_inv_data(clk);
+	unsigned int val;
+
+	val = meson_parm_read(clk->map, &tph->ph);
+
+	return meson_clk_degrees_from_val(val, tph->ph.width);
+}
+
+static int meson_sclk_ws_inv_set_phase(struct clk_hw *hw, int degrees)
+{
+	struct clk_regmap *clk = to_clk_regmap(hw);
+	struct meson_sclk_ws_inv_data *tph = meson_sclk_ws_inv_data(clk);
+	unsigned int val;
+
+	val = meson_clk_degrees_to_val(degrees, tph->ph.width);
+	meson_parm_write(clk->map, &tph->ph, val);
+	meson_parm_write(clk->map, &tph->ws, val ? 0 : 1);
+	return 0;
+}
+
+const struct clk_ops meson_sclk_ws_inv_ops = {
+	.init		= meson_sclk_ws_inv_sync,
+	.get_phase	= meson_sclk_ws_inv_get_phase,
+	.set_phase	= meson_sclk_ws_inv_set_phase,
+};
+EXPORT_SYMBOL_GPL(meson_sclk_ws_inv_ops);
+
+
 MODULE_DESCRIPTION("Amlogic phase driver");
 MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
 MODULE_LICENSE("GPL v2");

drivers/clk/meson/clk-phase.h

@@ -20,7 +20,13 @@ struct meson_clk_triphase_data {
 	struct parm ph2;
 };
 
+struct meson_sclk_ws_inv_data {
+	struct parm ph;
+	struct parm ws;
+};
+
 extern const struct clk_ops meson_clk_phase_ops;
 extern const struct clk_ops meson_clk_triphase_ops;
+extern const struct clk_ops meson_sclk_ws_inv_ops;
 
 #endif /* __MESON_CLK_PHASE_H */