This is a feature that can also be found in sprd composite clocks, provide a bunch of helpers that can be reused later on. Original-by: Xiaolong Zhang <xiaolong.zhang@xxxxxxxxxxxxxx> Signed-off-by: Chunyan Zhang <chunyan.zhang@xxxxxxxxxxxxxx> --- drivers/clk/sprd/Makefile | 1 + drivers/clk/sprd/div.c | 98 +++++++++++++++++++++++++++++++++++++++++++++++ drivers/clk/sprd/div.h | 77 +++++++++++++++++++++++++++++++++++++ 3 files changed, 176 insertions(+) create mode 100644 drivers/clk/sprd/div.c create mode 100644 drivers/clk/sprd/div.h diff --git a/drivers/clk/sprd/Makefile b/drivers/clk/sprd/Makefile index cee36b5..80e6039 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 0000000..8ba6642 --- /dev/null +++ b/drivers/clk/sprd/div.c @@ -0,0 +1,98 @@ +/* + * Spreadtrum divider clock driver + * + * Copyright (C) 2017 Spreadtrum, Inc. + * + * SPDX-License-Identifier: GPL-2.0 + */ + +#include <linux/clk-provider.h> + +#include "div.h" + +DEFINE_SPINLOCK(sprd_div_lock); +EXPORT_SYMBOL_GPL(sprd_div_lock); + +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; + u32 reg; + + reg = sprd_clk_readl(common); + 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 flags; + unsigned long val; + u32 reg; + + val = divider_get_val(rate, parent_rate, NULL, + div->width, 0); + + spin_lock_irqsave(common->lock, flags); + + reg = sprd_clk_readl(common); + reg &= ~GENMASK(div->width + div->shift - 1, div->shift); + + sprd_clk_writel(reg | (val << div->shift), common); + + spin_unlock_irqrestore(common->lock, flags); + + 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 0000000..128348e --- /dev/null +++ b/drivers/clk/sprd/div.h @@ -0,0 +1,77 @@ +/* + * Spreadtrum divider clock driver + * + * Copyright (C) 2017 Spreadtrum, Inc. + * + * SPDX-License-Identifier: GPL-2.0 + */ + +#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 = { \ + .reg = _reg, \ + .lock = &sprd_div_lock, \ + .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; +extern spinlock_t sprd_div_lock; + +#endif /* _SPRD_DIV_H_ */ -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html