From ac825c0dd7370ae1b9a1a4346f895728e09d9cc7 Mon Sep 17 00:00:00 2001 From: John Crispin Date: Wed, 1 Jul 2015 07:58:44 +0200 Subject: [PATCH 70/76] clk: mediatek: Export CPU mux clocks for CPU frequency control This patch adds CPU mux clocks which are used by Mediatek cpufreq driver for intermediate clock source switching. Changes in v3: - Rebase to 4.2-rc1 - Fix some issues of v2 Changes in v2: - Remove use of .determine_rate callback Signed-off-by: Pi-Cheng Chen --- drivers/clk/mediatek/Makefile | 2 +- drivers/clk/mediatek/clk-cpumux.c | 119 +++++++++++++++++++++++++++++++++++++ drivers/clk/mediatek/clk-cpumux.h | 30 ++++++++++ 3 files changed, 150 insertions(+), 1 deletion(-) create mode 100644 drivers/clk/mediatek/clk-cpumux.c create mode 100644 drivers/clk/mediatek/clk-cpumux.h --- a/drivers/clk/mediatek/Makefile +++ b/drivers/clk/mediatek/Makefile @@ -1,4 +1,4 @@ -obj-y += clk-mtk.o clk-pll.o clk-gate.o +obj-y += clk-mtk.o clk-pll.o clk-gate.o clk-cpumux.o obj-$(CONFIG_RESET_CONTROLLER) += reset.o obj-y += clk-mt7623.o obj-y += clk-mt8135.o --- /dev/null +++ b/drivers/clk/mediatek/clk-cpumux.c @@ -0,0 +1,119 @@ +/* + * Copyright (c) 2015 Linaro Ltd. + * Author: Pi-Cheng Chen + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include + +#include "clk-mtk.h" +#include "clk-cpumux.h" + +static inline struct mtk_clk_cpumux *to_clk_mux(struct clk_hw *_hw) +{ + return container_of(_hw, struct mtk_clk_cpumux, hw); +} + +static u8 clk_cpumux_get_parent(struct clk_hw *hw) +{ + struct mtk_clk_cpumux *mux = to_clk_mux(hw); + int num_parents = __clk_get_num_parents(hw->clk); + unsigned int val; + + regmap_read(mux->regmap, mux->reg, &val); + + val >>= mux->shift; + val &= mux->mask; + + if (val >= num_parents) + return -EINVAL; + + return val; +} + +static int clk_cpumux_set_parent(struct clk_hw *hw, u8 index) +{ + struct mtk_clk_cpumux *mux = to_clk_mux(hw); + u32 mask, val; + + val = index << mux->shift; + mask = mux->mask << mux->shift; + + return regmap_update_bits(mux->regmap, mux->reg, mask, val); +} + +static const struct clk_ops clk_cpumux_ops = { + .get_parent = clk_cpumux_get_parent, + .set_parent = clk_cpumux_set_parent, +}; + +static struct clk *mtk_clk_register_cpumux(const struct mtk_composite *mux, + struct regmap *regmap) +{ + struct mtk_clk_cpumux *cpumux; + struct clk *clk; + struct clk_init_data init; + + cpumux = kzalloc(sizeof(*cpumux), GFP_KERNEL); + if (!cpumux) + return ERR_PTR(-ENOMEM); + + init.name = mux->name; + init.ops = &clk_cpumux_ops; + init.parent_names = mux->parent_names; + init.num_parents = mux->num_parents; + init.flags = mux->flags; + + cpumux->reg = mux->mux_reg; + cpumux->shift = mux->mux_shift; + cpumux->mask = BIT(mux->mux_width) - 1; + cpumux->regmap = regmap; + cpumux->hw.init = &init; + + clk = clk_register(NULL, &cpumux->hw); + if (IS_ERR(clk)) + kfree(cpumux); + + return clk; +} + +int mtk_clk_register_cpumuxes(struct device_node *node, + const struct mtk_composite *clks, int num, + struct clk_onecell_data *clk_data) +{ + int i; + struct clk *clk; + struct regmap *regmap; + + regmap = syscon_node_to_regmap(node); + if (IS_ERR(regmap)) { + pr_err("Cannot find regmap for %s: %d\n", node->full_name, + PTR_ERR(regmap)); + return PTR_ERR(regmap); + } + + for (i = 0; i < num; i++) { + const struct mtk_composite *mux = &clks[i]; + + clk = mtk_clk_register_cpumux(mux, regmap); + if (IS_ERR(clk)) { + pr_err("Failed to register clk %s: %ld\n", + mux->name, PTR_ERR(clk)); + continue; + } + + clk_data->clks[mux->id] = clk; + } + + return 0; +} --- /dev/null +++ b/drivers/clk/mediatek/clk-cpumux.h @@ -0,0 +1,30 @@ +/* + * Copyright (c) 2015 Linaro Ltd. + * Author: Pi-Cheng Chen + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#ifndef __DRV_CLK_CPUMUX_H +#define __DRV_CLK_CPUMUX_H + +struct mtk_clk_cpumux { + struct clk_hw hw; + struct regmap *regmap; + u32 reg; + u32 mask; + u8 shift; +}; + +int mtk_clk_register_cpumuxes(struct device_node *node, + const struct mtk_composite *clks, int num, + struct clk_onecell_data *clk_data); + +#endif /* __DRV_CLK_CPUMUX_H */