This is a feature that can also be found in sprd composite clocks, provide two 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 | 2 +- drivers/clk/sprd/ccu_mux.c | 82 ++++++++++++++++++++++++++++++++++++++++++++++ drivers/clk/sprd/ccu_mux.h | 63 +++++++++++++++++++++++++++++++++++ 3 files changed, 146 insertions(+), 1 deletion(-) create mode 100644 drivers/clk/sprd/ccu_mux.c create mode 100644 drivers/clk/sprd/ccu_mux.h diff --git a/drivers/clk/sprd/Makefile b/drivers/clk/sprd/Makefile index 333e2b2..dc89790 100644 --- a/drivers/clk/sprd/Makefile +++ b/drivers/clk/sprd/Makefile @@ -1,3 +1,3 @@ ifneq ($(CONFIG_OF),) -obj-y += ccu_common.o ccu_gate.o +obj-y += ccu_common.o ccu_gate.o ccu_mux.o endif diff --git a/drivers/clk/sprd/ccu_mux.c b/drivers/clk/sprd/ccu_mux.c new file mode 100644 index 0000000..51c744e --- /dev/null +++ b/drivers/clk/sprd/ccu_mux.c @@ -0,0 +1,82 @@ +/* + * Spreadtrum multiplexer clock driver + * + * Copyright (C) 2017 Spreadtrum, Inc. + * + * SPDX-License-Identifier: GPL-2.0 + */ + +#include <linux/clk.h> +#include <linux/clk-provider.h> + +#include "ccu_mux.h" + +DEFINE_SPINLOCK(mux_lock); + +u8 ccu_mux_helper_get_parent(struct ccu_common *common, + struct ccu_mux_internal *mux) +{ + u32 reg; + u8 parent; + int num_parents; + int i; + + reg = ccu_readl(common); + parent = reg >> mux->shift; + parent &= (1 << mux->width) - 1; + + if (mux->table) { + num_parents = clk_hw_get_num_parents(&common->hw); + + for (i = 0; i < num_parents; i++) + if (parent == mux->table[i] || + (i < (num_parents - 1) && parent > mux->table[i] && + parent < mux->table[i + 1])) + return i; + if (i == num_parents) + return i - 1; + } + + return parent; +} + +static u8 ccu_mux_get_parent(struct clk_hw *hw) +{ + struct ccu_mux *cm = hw_to_ccu_mux(hw); + + return ccu_mux_helper_get_parent(&cm->common, &cm->mux); +} + +int ccu_mux_helper_set_parent(struct ccu_common *common, + struct ccu_mux_internal *mux, + u8 index) +{ + unsigned long flags = 0; + u32 reg; + + if (mux->table) + index = mux->table[index]; + + spin_lock_irqsave(common->lock, flags); + + reg = ccu_readl(common); + reg &= ~GENMASK(mux->width + mux->shift - 1, mux->shift); + ccu_writel(reg | (index << mux->shift), common); + + spin_unlock_irqrestore(common->lock, flags); + + return 0; +} + +static int ccu_mux_set_parent(struct clk_hw *hw, u8 index) +{ + struct ccu_mux *cm = hw_to_ccu_mux(hw); + + return ccu_mux_helper_set_parent(&cm->common, &cm->mux, index); +} + +const struct clk_ops ccu_mux_ops = { + .get_parent = ccu_mux_get_parent, + .set_parent = ccu_mux_set_parent, + .determine_rate = __clk_mux_determine_rate, +}; diff --git a/drivers/clk/sprd/ccu_mux.h b/drivers/clk/sprd/ccu_mux.h new file mode 100644 index 0000000..f3e3fb4 --- /dev/null +++ b/drivers/clk/sprd/ccu_mux.h @@ -0,0 +1,63 @@ +/* + * Spreadtrum multiplexer clock driver + * + * Copyright (C) 2017 Spreadtrum, Inc. + * + * SPDX-License-Identifier: GPL-2.0 + */ + +#ifndef _CCU_MUX_H_ +#define _CCU_MUX_H_ + +#include "ccu_common.h" + +struct ccu_mux_internal { + u8 shift; + u8 width; + const u8 *table; +}; + +struct ccu_mux { + struct ccu_mux_internal mux; + struct ccu_common common; +}; + +#define _SPRD_CCU_MUX(_shift, _width, _table) \ + { \ + .shift = _shift, \ + .width = _width, \ + .table = _table, \ + } + +#define SPRD_CCU_MUX(_struct, _name, _parents, _table, \ + _reg, _shift, _width, \ + _flags) \ + struct ccu_mux _struct = { \ + .mux = _SPRD_CCU_MUX(_shift, _width, _table), \ + .common = { \ + .reg = _reg, \ + .lock = &mux_lock, \ + .hw.init = CLK_HW_INIT_PARENTS(_name, \ + _parents, \ + &ccu_mux_ops,\ + _flags), \ + } \ + } + +static inline struct ccu_mux *hw_to_ccu_mux(struct clk_hw *hw) +{ + struct ccu_common *common = hw_to_ccu_common(hw); + + return container_of(common, struct ccu_mux, common); +} + +extern const struct clk_ops ccu_mux_ops; +extern spinlock_t mux_lock; + +u8 ccu_mux_helper_get_parent(struct ccu_common *common, + struct ccu_mux_internal *mux); +int ccu_mux_helper_set_parent(struct ccu_common *common, + struct ccu_mux_internal *mux, + u8 index); + +#endif /* _CCU_MUX_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