diff options
Diffstat (limited to 'drivers/clk/clk-max-gen.c')
| -rw-r--r-- | drivers/clk/clk-max-gen.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/drivers/clk/clk-max-gen.c b/drivers/clk/clk-max-gen.c new file mode 100644 index 000000000..6505049d5 --- /dev/null +++ b/drivers/clk/clk-max-gen.c @@ -0,0 +1,192 @@ +/* + * clk-max-gen.c - Generic clock driver for Maxim PMICs clocks + * + * Copyright (C) 2014 Google, Inc + * + * Copyright (C) 2012 Samsung Electornics + * Jonghwa Lee <jonghwa3.lee@samsung.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. + * + * This driver is based on clk-max77686.c + * + */ + +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/regmap.h> +#include <linux/platform_device.h> +#include <linux/clk-provider.h> +#include <linux/mutex.h> +#include <linux/clkdev.h> +#include <linux/of.h> +#include <linux/export.h> + +struct max_gen_clk { + struct regmap *regmap; + u32 mask; + u32 reg; + struct clk_hw hw; +}; + +static struct max_gen_clk *to_max_gen_clk(struct clk_hw *hw) +{ + return container_of(hw, struct max_gen_clk, hw); +} + +static int max_gen_clk_prepare(struct clk_hw *hw) +{ + struct max_gen_clk *max_gen = to_max_gen_clk(hw); + + return regmap_update_bits(max_gen->regmap, max_gen->reg, + max_gen->mask, max_gen->mask); +} + +static void max_gen_clk_unprepare(struct clk_hw *hw) +{ + struct max_gen_clk *max_gen = to_max_gen_clk(hw); + + regmap_update_bits(max_gen->regmap, max_gen->reg, + max_gen->mask, ~max_gen->mask); +} + +static int max_gen_clk_is_prepared(struct clk_hw *hw) +{ + struct max_gen_clk *max_gen = to_max_gen_clk(hw); + int ret; + u32 val; + + ret = regmap_read(max_gen->regmap, max_gen->reg, &val); + + if (ret < 0) + return -EINVAL; + + return val & max_gen->mask; +} + +static unsigned long max_gen_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + return 32768; +} + +struct clk_ops max_gen_clk_ops = { + .prepare = max_gen_clk_prepare, + .unprepare = max_gen_clk_unprepare, + .is_prepared = max_gen_clk_is_prepared, + .recalc_rate = max_gen_recalc_rate, +}; +EXPORT_SYMBOL_GPL(max_gen_clk_ops); + +static struct clk *max_gen_clk_register(struct device *dev, + struct max_gen_clk *max_gen) +{ + struct clk *clk; + struct clk_hw *hw = &max_gen->hw; + int ret; + + clk = devm_clk_register(dev, hw); + if (IS_ERR(clk)) + return clk; + + ret = clk_register_clkdev(clk, hw->init->name, NULL); + + if (ret) + return ERR_PTR(ret); + + return clk; +} + +int max_gen_clk_probe(struct platform_device *pdev, struct regmap *regmap, + u32 reg, struct clk_init_data *clks_init, int num_init) +{ + int i, ret; + struct max_gen_clk *max_gen_clks; + struct clk **clocks; + struct device *dev = pdev->dev.parent; + const char *clk_name; + struct clk_init_data *init; + + clocks = devm_kzalloc(dev, sizeof(struct clk *) * num_init, GFP_KERNEL); + if (!clocks) + return -ENOMEM; + + max_gen_clks = devm_kzalloc(dev, sizeof(struct max_gen_clk) + * num_init, GFP_KERNEL); + if (!max_gen_clks) + return -ENOMEM; + + for (i = 0; i < num_init; i++) { + max_gen_clks[i].regmap = regmap; + max_gen_clks[i].mask = 1 << i; + max_gen_clks[i].reg = reg; + + init = devm_kzalloc(dev, sizeof(*init), GFP_KERNEL); + if (!init) + return -ENOMEM; + + if (dev->of_node && + !of_property_read_string_index(dev->of_node, + "clock-output-names", + i, &clk_name)) + init->name = clk_name; + else + init->name = clks_init[i].name; + + init->ops = clks_init[i].ops; + init->flags = clks_init[i].flags; + + max_gen_clks[i].hw.init = init; + + clocks[i] = max_gen_clk_register(dev, &max_gen_clks[i]); + if (IS_ERR(clocks[i])) { + ret = PTR_ERR(clocks[i]); + dev_err(dev, "failed to register %s\n", + max_gen_clks[i].hw.init->name); + return ret; + } + } + + platform_set_drvdata(pdev, clocks); + + if (dev->of_node) { + struct clk_onecell_data *of_data; + + of_data = devm_kzalloc(dev, sizeof(*of_data), GFP_KERNEL); + if (!of_data) + return -ENOMEM; + + of_data->clks = clocks; + of_data->clk_num = num_init; + ret = of_clk_add_provider(dev->of_node, of_clk_src_onecell_get, + of_data); + + if (ret) { + dev_err(dev, "failed to register OF clock provider\n"); + return ret; + } + } + + return 0; +} +EXPORT_SYMBOL_GPL(max_gen_clk_probe); + +int max_gen_clk_remove(struct platform_device *pdev, int num_init) +{ + struct device *dev = pdev->dev.parent; + + if (dev->of_node) + of_clk_del_provider(dev->of_node); + + return 0; +} +EXPORT_SYMBOL_GPL(max_gen_clk_remove); |