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path: root/drivers/clk/meson/clk-triphase.c
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Diffstat (limited to 'drivers/clk/meson/clk-triphase.c')
-rw-r--r--drivers/clk/meson/clk-triphase.c68
1 files changed, 68 insertions, 0 deletions
diff --git a/drivers/clk/meson/clk-triphase.c b/drivers/clk/meson/clk-triphase.c
new file mode 100644
index 000000000000..4a59936251e5
--- /dev/null
+++ b/drivers/clk/meson/clk-triphase.c
@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * Copyright (c) 2018 BayLibre, SAS.
+ * Author: Jerome Brunet <jbrunet@baylibre.com>
+ */
+
+#include <linux/clk-provider.h>
+#include "clkc-audio.h"
+
+/*
+ * This is a special clock for the audio controller.
+ * The phase of mst_sclk clock output can be controlled independently
+ * for the outside world (ph0), the tdmout (ph1) and tdmin (ph2).
+ * Controlling these 3 phases as just one makes things simpler and
+ * give the same clock view to all the element on the i2s bus.
+ * If necessary, we can still control the phase in the tdm block
+ * which makes these independent control redundant.
+ */
+static inline struct meson_clk_triphase_data *
+meson_clk_triphase_data(struct clk_regmap *clk)
+{
+ return (struct meson_clk_triphase_data *)clk->data;
+}
+
+static void meson_clk_triphase_sync(struct clk_hw *hw)
+{
+ struct clk_regmap *clk = to_clk_regmap(hw);
+ struct meson_clk_triphase_data *tph = meson_clk_triphase_data(clk);
+ unsigned int val;
+
+ /* Get phase 0 and sync it to phase 1 and 2 */
+ val = meson_parm_read(clk->map, &tph->ph0);
+ meson_parm_write(clk->map, &tph->ph1, val);
+ meson_parm_write(clk->map, &tph->ph2, val);
+}
+
+static int meson_clk_triphase_get_phase(struct clk_hw *hw)
+{
+ struct clk_regmap *clk = to_clk_regmap(hw);
+ struct meson_clk_triphase_data *tph = meson_clk_triphase_data(clk);
+ unsigned int val;
+
+ /* Phase are in sync, reading phase 0 is enough */
+ val = meson_parm_read(clk->map, &tph->ph0);
+
+ return meson_clk_degrees_from_val(val, tph->ph0.width);
+}
+
+static int meson_clk_triphase_set_phase(struct clk_hw *hw, int degrees)
+{
+ struct clk_regmap *clk = to_clk_regmap(hw);
+ struct meson_clk_triphase_data *tph = meson_clk_triphase_data(clk);
+ unsigned int val;
+
+ val = meson_clk_degrees_to_val(degrees, tph->ph0.width);
+ meson_parm_write(clk->map, &tph->ph0, val);
+ meson_parm_write(clk->map, &tph->ph1, val);
+ meson_parm_write(clk->map, &tph->ph2, val);
+
+ return 0;
+}
+
+const struct clk_ops meson_clk_triphase_ops = {
+ .init = meson_clk_triphase_sync,
+ .get_phase = meson_clk_triphase_get_phase,
+ .set_phase = meson_clk_triphase_set_phase,
+};
+EXPORT_SYMBOL_GPL(meson_clk_triphase_ops);