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Diffstat (limited to '')
-rw-r--r-- | drivers/clk/meson/clk-phase.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/drivers/clk/meson/clk-phase.c b/drivers/clk/meson/clk-phase.c new file mode 100644 index 000000000..a6763439f --- /dev/null +++ b/drivers/clk/meson/clk-phase.c @@ -0,0 +1,186 @@ +// 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 <linux/module.h> + +#include "clk-regmap.h" +#include "clk-phase.h" + +#define phase_step(_width) (360 / (1 << (_width))) + +static inline struct meson_clk_phase_data * +meson_clk_phase_data(struct clk_regmap *clk) +{ + return (struct meson_clk_phase_data *)clk->data; +} + +static int meson_clk_degrees_from_val(unsigned int val, unsigned int width) +{ + return phase_step(width) * val; +} + +static unsigned int meson_clk_degrees_to_val(int degrees, unsigned int width) +{ + unsigned int val = DIV_ROUND_CLOSEST(degrees, phase_step(width)); + + /* + * This last calculation is here for cases when degrees is rounded + * to 360, in which case val == (1 << width). + */ + return val % (1 << width); +} + +static int meson_clk_phase_get_phase(struct clk_hw *hw) +{ + struct clk_regmap *clk = to_clk_regmap(hw); + struct meson_clk_phase_data *phase = meson_clk_phase_data(clk); + unsigned int val; + + val = meson_parm_read(clk->map, &phase->ph); + + return meson_clk_degrees_from_val(val, phase->ph.width); +} + +static int meson_clk_phase_set_phase(struct clk_hw *hw, int degrees) +{ + struct clk_regmap *clk = to_clk_regmap(hw); + struct meson_clk_phase_data *phase = meson_clk_phase_data(clk); + unsigned int val; + + val = meson_clk_degrees_to_val(degrees, phase->ph.width); + meson_parm_write(clk->map, &phase->ph, val); + + return 0; +} + +const struct clk_ops meson_clk_phase_ops = { + .get_phase = meson_clk_phase_get_phase, + .set_phase = meson_clk_phase_set_phase, +}; +EXPORT_SYMBOL_GPL(meson_clk_phase_ops); + +/* + * 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 int 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); + + return 0; +} + +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); + +/* + * 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"); |