From e3f05d3b18e6cfbddaed687b4a57c280015acc1f Mon Sep 17 00:00:00 2001 From: Chunyan Zhang Date: Thu, 7 Dec 2017 20:57:08 +0800 Subject: clk: sprd: add divider clock support This is a feature that can also be found in sprd composite clocks, provide a bunch of helpers that can be reused later on. Signed-off-by: Chunyan Zhang Signed-off-by: Stephen Boyd --- drivers/clk/sprd/Makefile | 1 + drivers/clk/sprd/div.c | 90 +++++++++++++++++++++++++++++++++++++++++++++++ drivers/clk/sprd/div.h | 75 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 166 insertions(+) create mode 100644 drivers/clk/sprd/div.c create mode 100644 drivers/clk/sprd/div.h (limited to 'drivers') diff --git a/drivers/clk/sprd/Makefile b/drivers/clk/sprd/Makefile index cee36b511109..80e603905c90 100644 --- a/drivers/clk/sprd/Makefile +++ b/drivers/clk/sprd/Makefile @@ -3,3 +3,4 @@ obj-$(CONFIG_SPRD_COMMON_CLK) += clk-sprd.o clk-sprd-y += common.o clk-sprd-y += gate.o clk-sprd-y += mux.o +clk-sprd-y += div.o diff --git a/drivers/clk/sprd/div.c b/drivers/clk/sprd/div.c new file mode 100644 index 000000000000..887a8633fdc9 --- /dev/null +++ b/drivers/clk/sprd/div.c @@ -0,0 +1,90 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Spreadtrum divider clock driver +// +// Copyright (C) 2017 Spreadtrum, Inc. +// Author: Chunyan Zhang + +#include + +#include "div.h" + +long sprd_div_helper_round_rate(struct sprd_clk_common *common, + const struct sprd_div_internal *div, + unsigned long rate, + unsigned long *parent_rate) +{ + return divider_round_rate(&common->hw, rate, parent_rate, + NULL, div->width, 0); +} +EXPORT_SYMBOL_GPL(sprd_div_helper_round_rate); + +static long sprd_div_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + struct sprd_div *cd = hw_to_sprd_div(hw); + + return sprd_div_helper_round_rate(&cd->common, &cd->div, + rate, parent_rate); +} + +unsigned long sprd_div_helper_recalc_rate(struct sprd_clk_common *common, + const struct sprd_div_internal *div, + unsigned long parent_rate) +{ + unsigned long val; + unsigned int reg; + + regmap_read(common->regmap, common->reg, ®); + val = reg >> div->shift; + val &= (1 << div->width) - 1; + + return divider_recalc_rate(&common->hw, parent_rate, val, NULL, 0); +} +EXPORT_SYMBOL_GPL(sprd_div_helper_recalc_rate); + +static unsigned long sprd_div_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct sprd_div *cd = hw_to_sprd_div(hw); + + return sprd_div_helper_recalc_rate(&cd->common, &cd->div, parent_rate); +} + +int sprd_div_helper_set_rate(const struct sprd_clk_common *common, + const struct sprd_div_internal *div, + unsigned long rate, + unsigned long parent_rate) +{ + unsigned long val; + unsigned int reg; + + val = divider_get_val(rate, parent_rate, NULL, + div->width, 0); + + regmap_read(common->regmap, common->reg, ®); + reg &= ~GENMASK(div->width + div->shift - 1, div->shift); + + regmap_write(common->regmap, common->reg, + reg | (val << div->shift)); + + return 0; + +} +EXPORT_SYMBOL_GPL(sprd_div_helper_set_rate); + +static int sprd_div_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct sprd_div *cd = hw_to_sprd_div(hw); + + return sprd_div_helper_set_rate(&cd->common, &cd->div, + rate, parent_rate); +} + +const struct clk_ops sprd_div_ops = { + .recalc_rate = sprd_div_recalc_rate, + .round_rate = sprd_div_round_rate, + .set_rate = sprd_div_set_rate, +}; +EXPORT_SYMBOL_GPL(sprd_div_ops); diff --git a/drivers/clk/sprd/div.h b/drivers/clk/sprd/div.h new file mode 100644 index 000000000000..b3033d24d431 --- /dev/null +++ b/drivers/clk/sprd/div.h @@ -0,0 +1,75 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Spreadtrum divider clock driver +// +// Copyright (C) 2017 Spreadtrum, Inc. +// Author: Chunyan Zhang + +#ifndef _SPRD_DIV_H_ +#define _SPRD_DIV_H_ + +#include "common.h" + +/** + * struct sprd_div_internal - Internal divider description + * @shift: Bit offset of the divider in its register + * @width: Width of the divider field in its register + * + * That structure represents a single divider, and is meant to be + * embedded in other structures representing the various clock + * classes. + */ +struct sprd_div_internal { + u8 shift; + u8 width; +}; + +#define _SPRD_DIV_CLK(_shift, _width) \ + { \ + .shift = _shift, \ + .width = _width, \ + } + +struct sprd_div { + struct sprd_div_internal div; + struct sprd_clk_common common; +}; + +#define SPRD_DIV_CLK(_struct, _name, _parent, _reg, \ + _shift, _width, _flags) \ + struct sprd_div _struct = { \ + .div = _SPRD_DIV_CLK(_shift, _width), \ + .common = { \ + .regmap = NULL, \ + .reg = _reg, \ + .hw.init = CLK_HW_INIT(_name, \ + _parent, \ + &sprd_div_ops, \ + _flags), \ + } \ + } + +static inline struct sprd_div *hw_to_sprd_div(const struct clk_hw *hw) +{ + struct sprd_clk_common *common = hw_to_sprd_clk_common(hw); + + return container_of(common, struct sprd_div, common); +} + +long sprd_div_helper_round_rate(struct sprd_clk_common *common, + const struct sprd_div_internal *div, + unsigned long rate, + unsigned long *parent_rate); + +unsigned long sprd_div_helper_recalc_rate(struct sprd_clk_common *common, + const struct sprd_div_internal *div, + unsigned long parent_rate); + +int sprd_div_helper_set_rate(const struct sprd_clk_common *common, + const struct sprd_div_internal *div, + unsigned long rate, + unsigned long parent_rate); + +extern const struct clk_ops sprd_div_ops; + +#endif /* _SPRD_DIV_H_ */ -- cgit v1.2.3-59-g8ed1b