diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/clk/mediatek/clk-mux.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/clk/mediatek/clk-mux.c')
-rw-r--r-- | drivers/clk/mediatek/clk-mux.c | 310 |
1 files changed, 310 insertions, 0 deletions
diff --git a/drivers/clk/mediatek/clk-mux.c b/drivers/clk/mediatek/clk-mux.c new file mode 100644 index 000000000..ba1720b9e --- /dev/null +++ b/drivers/clk/mediatek/clk-mux.c @@ -0,0 +1,310 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2018 MediaTek Inc. + * Author: Owen Chen <owen.chen@mediatek.com> + */ + +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/compiler_types.h> +#include <linux/container_of.h> +#include <linux/err.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/spinlock.h> +#include <linux/slab.h> + +#include "clk-mux.h" + +struct mtk_clk_mux { + struct clk_hw hw; + struct regmap *regmap; + const struct mtk_mux *data; + spinlock_t *lock; + bool reparent; +}; + +static inline struct mtk_clk_mux *to_mtk_clk_mux(struct clk_hw *hw) +{ + return container_of(hw, struct mtk_clk_mux, hw); +} + +static int mtk_clk_mux_enable_setclr(struct clk_hw *hw) +{ + struct mtk_clk_mux *mux = to_mtk_clk_mux(hw); + unsigned long flags = 0; + + if (mux->lock) + spin_lock_irqsave(mux->lock, flags); + else + __acquire(mux->lock); + + regmap_write(mux->regmap, mux->data->clr_ofs, + BIT(mux->data->gate_shift)); + + /* + * If the parent has been changed when the clock was disabled, it will + * not be effective yet. Set the update bit to ensure the mux gets + * updated. + */ + if (mux->reparent && mux->data->upd_shift >= 0) { + regmap_write(mux->regmap, mux->data->upd_ofs, + BIT(mux->data->upd_shift)); + mux->reparent = false; + } + + if (mux->lock) + spin_unlock_irqrestore(mux->lock, flags); + else + __release(mux->lock); + + return 0; +} + +static void mtk_clk_mux_disable_setclr(struct clk_hw *hw) +{ + struct mtk_clk_mux *mux = to_mtk_clk_mux(hw); + + regmap_write(mux->regmap, mux->data->set_ofs, + BIT(mux->data->gate_shift)); +} + +static int mtk_clk_mux_is_enabled(struct clk_hw *hw) +{ + struct mtk_clk_mux *mux = to_mtk_clk_mux(hw); + u32 val; + + regmap_read(mux->regmap, mux->data->mux_ofs, &val); + + return (val & BIT(mux->data->gate_shift)) == 0; +} + +static u8 mtk_clk_mux_get_parent(struct clk_hw *hw) +{ + struct mtk_clk_mux *mux = to_mtk_clk_mux(hw); + u32 mask = GENMASK(mux->data->mux_width - 1, 0); + u32 val; + + regmap_read(mux->regmap, mux->data->mux_ofs, &val); + val = (val >> mux->data->mux_shift) & mask; + + return val; +} + +static int mtk_clk_mux_set_parent_setclr_lock(struct clk_hw *hw, u8 index) +{ + struct mtk_clk_mux *mux = to_mtk_clk_mux(hw); + u32 mask = GENMASK(mux->data->mux_width - 1, 0); + u32 val, orig; + unsigned long flags = 0; + + if (mux->lock) + spin_lock_irqsave(mux->lock, flags); + else + __acquire(mux->lock); + + regmap_read(mux->regmap, mux->data->mux_ofs, &orig); + val = (orig & ~(mask << mux->data->mux_shift)) + | (index << mux->data->mux_shift); + + if (val != orig) { + regmap_write(mux->regmap, mux->data->clr_ofs, + mask << mux->data->mux_shift); + regmap_write(mux->regmap, mux->data->set_ofs, + index << mux->data->mux_shift); + + if (mux->data->upd_shift >= 0) { + regmap_write(mux->regmap, mux->data->upd_ofs, + BIT(mux->data->upd_shift)); + mux->reparent = true; + } + } + + if (mux->lock) + spin_unlock_irqrestore(mux->lock, flags); + else + __release(mux->lock); + + return 0; +} + +static int mtk_clk_mux_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + struct mtk_clk_mux *mux = to_mtk_clk_mux(hw); + + return clk_mux_determine_rate_flags(hw, req, mux->data->flags); +} + +const struct clk_ops mtk_mux_clr_set_upd_ops = { + .get_parent = mtk_clk_mux_get_parent, + .set_parent = mtk_clk_mux_set_parent_setclr_lock, + .determine_rate = mtk_clk_mux_determine_rate, +}; +EXPORT_SYMBOL_GPL(mtk_mux_clr_set_upd_ops); + +const struct clk_ops mtk_mux_gate_clr_set_upd_ops = { + .enable = mtk_clk_mux_enable_setclr, + .disable = mtk_clk_mux_disable_setclr, + .is_enabled = mtk_clk_mux_is_enabled, + .get_parent = mtk_clk_mux_get_parent, + .set_parent = mtk_clk_mux_set_parent_setclr_lock, + .determine_rate = mtk_clk_mux_determine_rate, +}; +EXPORT_SYMBOL_GPL(mtk_mux_gate_clr_set_upd_ops); + +static struct clk_hw *mtk_clk_register_mux(const struct mtk_mux *mux, + struct regmap *regmap, + spinlock_t *lock) +{ + struct mtk_clk_mux *clk_mux; + struct clk_init_data init = {}; + int ret; + + clk_mux = kzalloc(sizeof(*clk_mux), GFP_KERNEL); + if (!clk_mux) + return ERR_PTR(-ENOMEM); + + init.name = mux->name; + init.flags = mux->flags | CLK_SET_RATE_PARENT; + init.parent_names = mux->parent_names; + init.num_parents = mux->num_parents; + init.ops = mux->ops; + + clk_mux->regmap = regmap; + clk_mux->data = mux; + clk_mux->lock = lock; + clk_mux->hw.init = &init; + + ret = clk_hw_register(NULL, &clk_mux->hw); + if (ret) { + kfree(clk_mux); + return ERR_PTR(ret); + } + + return &clk_mux->hw; +} + +static void mtk_clk_unregister_mux(struct clk_hw *hw) +{ + struct mtk_clk_mux *mux; + if (!hw) + return; + + mux = to_mtk_clk_mux(hw); + + clk_hw_unregister(hw); + kfree(mux); +} + +int mtk_clk_register_muxes(const struct mtk_mux *muxes, + int num, struct device_node *node, + spinlock_t *lock, + struct clk_hw_onecell_data *clk_data) +{ + struct regmap *regmap; + struct clk_hw *hw; + int i; + + regmap = device_node_to_regmap(node); + if (IS_ERR(regmap)) { + pr_err("Cannot find regmap for %pOF: %pe\n", node, regmap); + return PTR_ERR(regmap); + } + + for (i = 0; i < num; i++) { + const struct mtk_mux *mux = &muxes[i]; + + if (!IS_ERR_OR_NULL(clk_data->hws[mux->id])) { + pr_warn("%pOF: Trying to register duplicate clock ID: %d\n", + node, mux->id); + continue; + } + + hw = mtk_clk_register_mux(mux, regmap, lock); + + if (IS_ERR(hw)) { + pr_err("Failed to register clk %s: %pe\n", mux->name, + hw); + goto err; + } + + clk_data->hws[mux->id] = hw; + } + + return 0; + +err: + while (--i >= 0) { + const struct mtk_mux *mux = &muxes[i]; + + if (IS_ERR_OR_NULL(clk_data->hws[mux->id])) + continue; + + mtk_clk_unregister_mux(clk_data->hws[mux->id]); + clk_data->hws[mux->id] = ERR_PTR(-ENOENT); + } + + return PTR_ERR(hw); +} +EXPORT_SYMBOL_GPL(mtk_clk_register_muxes); + +void mtk_clk_unregister_muxes(const struct mtk_mux *muxes, int num, + struct clk_hw_onecell_data *clk_data) +{ + int i; + + if (!clk_data) + return; + + for (i = num; i > 0; i--) { + const struct mtk_mux *mux = &muxes[i - 1]; + + if (IS_ERR_OR_NULL(clk_data->hws[mux->id])) + continue; + + mtk_clk_unregister_mux(clk_data->hws[mux->id]); + clk_data->hws[mux->id] = ERR_PTR(-ENOENT); + } +} +EXPORT_SYMBOL_GPL(mtk_clk_unregister_muxes); + +/* + * This clock notifier is called when the frequency of the parent + * PLL clock is to be changed. The idea is to switch the parent to a + * stable clock, such as the main oscillator, while the PLL frequency + * stabilizes. + */ +static int mtk_clk_mux_notifier_cb(struct notifier_block *nb, + unsigned long event, void *_data) +{ + struct clk_notifier_data *data = _data; + struct clk_hw *hw = __clk_get_hw(data->clk); + struct mtk_mux_nb *mux_nb = to_mtk_mux_nb(nb); + int ret = 0; + + switch (event) { + case PRE_RATE_CHANGE: + mux_nb->original_index = mux_nb->ops->get_parent(hw); + ret = mux_nb->ops->set_parent(hw, mux_nb->bypass_index); + break; + case POST_RATE_CHANGE: + case ABORT_RATE_CHANGE: + ret = mux_nb->ops->set_parent(hw, mux_nb->original_index); + break; + } + + return notifier_from_errno(ret); +} + +int devm_mtk_clk_mux_notifier_register(struct device *dev, struct clk *clk, + struct mtk_mux_nb *mux_nb) +{ + mux_nb->nb.notifier_call = mtk_clk_mux_notifier_cb; + + return devm_clk_notifier_register(dev, clk, &mux_nb->nb); +} +EXPORT_SYMBOL_GPL(devm_mtk_clk_mux_notifier_register); + +MODULE_LICENSE("GPL"); |