diff options
Diffstat (limited to 'drivers/clk/uniphier/clk-uniphier-gate.c')
-rw-r--r-- | drivers/clk/uniphier/clk-uniphier-gate.c | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/drivers/clk/uniphier/clk-uniphier-gate.c b/drivers/clk/uniphier/clk-uniphier-gate.c new file mode 100644 index 000000000000..49142d44446d --- /dev/null +++ b/drivers/clk/uniphier/clk-uniphier-gate.c @@ -0,0 +1,97 @@ +/* + * Copyright (C) 2016 Socionext Inc. + * Author: Masahiro Yamada <yamada.masahiro@socionext.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * 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 <linux/clk-provider.h> +#include <linux/device.h> +#include <linux/regmap.h> + +#include "clk-uniphier.h" + +struct uniphier_clk_gate { + struct clk_hw hw; + struct regmap *regmap; + unsigned int reg; + unsigned int bit; +}; + +#define to_uniphier_clk_gate(_hw) \ + container_of(_hw, struct uniphier_clk_gate, hw) + +static int uniphier_clk_gate_endisable(struct clk_hw *hw, int enable) +{ + struct uniphier_clk_gate *gate = to_uniphier_clk_gate(hw); + + return regmap_write_bits(gate->regmap, gate->reg, BIT(gate->bit), + enable ? BIT(gate->bit) : 0); +} + +static int uniphier_clk_gate_enable(struct clk_hw *hw) +{ + return uniphier_clk_gate_endisable(hw, 1); +} + +static void uniphier_clk_gate_disable(struct clk_hw *hw) +{ + if (uniphier_clk_gate_endisable(hw, 0) < 0) + pr_warn("failed to disable clk\n"); +} + +static int uniphier_clk_gate_is_enabled(struct clk_hw *hw) +{ + struct uniphier_clk_gate *gate = to_uniphier_clk_gate(hw); + unsigned int val; + + if (regmap_read(gate->regmap, gate->reg, &val) < 0) + pr_warn("is_enabled() may return wrong result\n"); + + return !!(val & BIT(gate->bit)); +} + +static const struct clk_ops uniphier_clk_gate_ops = { + .enable = uniphier_clk_gate_enable, + .disable = uniphier_clk_gate_disable, + .is_enabled = uniphier_clk_gate_is_enabled, +}; + +struct clk_hw *uniphier_clk_register_gate(struct device *dev, + struct regmap *regmap, + const char *name, + const struct uniphier_clk_gate_data *data) +{ + struct uniphier_clk_gate *gate; + struct clk_init_data init; + int ret; + + gate = devm_kzalloc(dev, sizeof(*gate), GFP_KERNEL); + if (!gate) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &uniphier_clk_gate_ops; + init.flags = data->parent_name ? CLK_SET_RATE_PARENT : 0; + init.parent_names = data->parent_name ? &data->parent_name : NULL; + init.num_parents = data->parent_name ? 1 : 0; + + gate->regmap = regmap; + gate->reg = data->reg; + gate->bit = data->bit; + gate->hw.init = &init; + + ret = devm_clk_hw_register(dev, &gate->hw); + if (ret) + return ERR_PTR(ret); + + return &gate->hw; +} |