diff options
Diffstat (limited to 'drivers/clk/clk-max77686.c')
| -rw-r--r-- | drivers/clk/clk-max77686.c | 252 |
1 files changed, 252 insertions, 0 deletions
diff --git a/drivers/clk/clk-max77686.c b/drivers/clk/clk-max77686.c new file mode 100644 index 00000000000..3d7e8dd8fd5 --- /dev/null +++ b/drivers/clk/clk-max77686.c @@ -0,0 +1,252 @@ +/* + * clk-max77686.c - Clock driver for Maxim 77686 + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/mfd/max77686.h> +#include <linux/mfd/max77686-private.h> +#include <linux/clk-provider.h> +#include <linux/mutex.h> +#include <linux/clkdev.h> + +enum { + MAX77686_CLK_AP = 0, + MAX77686_CLK_CP, + MAX77686_CLK_PMIC, + MAX77686_CLKS_NUM, +}; + +struct max77686_clk { + struct max77686_dev *iodev; + u32 mask; + struct clk_hw hw; + struct clk_lookup *lookup; +}; + +static struct max77686_clk *to_max77686_clk(struct clk_hw *hw) +{ + return container_of(hw, struct max77686_clk, hw); +} + +static int max77686_clk_prepare(struct clk_hw *hw) +{ + struct max77686_clk *max77686 = to_max77686_clk(hw); + + return regmap_update_bits(max77686->iodev->regmap, + MAX77686_REG_32KHZ, max77686->mask, + max77686->mask); +} + +static void max77686_clk_unprepare(struct clk_hw *hw) +{ + struct max77686_clk *max77686 = to_max77686_clk(hw); + + regmap_update_bits(max77686->iodev->regmap, + MAX77686_REG_32KHZ, max77686->mask, ~max77686->mask); +} + +static int max77686_clk_is_prepared(struct clk_hw *hw) +{ + struct max77686_clk *max77686 = to_max77686_clk(hw); + int ret; + u32 val; + + ret = regmap_read(max77686->iodev->regmap, + MAX77686_REG_32KHZ, &val); + + if (ret < 0) + return -EINVAL; + + return val & max77686->mask; +} + +static unsigned long max77686_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + return 32768; +} + +static struct clk_ops max77686_clk_ops = { + .prepare = max77686_clk_prepare, + .unprepare = max77686_clk_unprepare, + .is_prepared = max77686_clk_is_prepared, + .recalc_rate = max77686_recalc_rate, +}; + +static struct clk_init_data max77686_clks_init[MAX77686_CLKS_NUM] = { + [MAX77686_CLK_AP] = { + .name = "32khz_ap", + .ops = &max77686_clk_ops, + .flags = CLK_IS_ROOT, + }, + [MAX77686_CLK_CP] = { + .name = "32khz_cp", + .ops = &max77686_clk_ops, + .flags = CLK_IS_ROOT, + }, + [MAX77686_CLK_PMIC] = { + .name = "32khz_pmic", + .ops = &max77686_clk_ops, + .flags = CLK_IS_ROOT, + }, +}; + +static struct clk *max77686_clk_register(struct device *dev, + struct max77686_clk *max77686) +{ + struct clk *clk; + struct clk_hw *hw = &max77686->hw; + + clk = clk_register(dev, hw); + if (IS_ERR(clk)) + return clk; + + max77686->lookup = kzalloc(sizeof(struct clk_lookup), GFP_KERNEL); + if (!max77686->lookup) + return ERR_PTR(-ENOMEM); + + max77686->lookup->con_id = hw->init->name; + max77686->lookup->clk = clk; + + clkdev_add(max77686->lookup); + + return clk; +} + +static int max77686_clk_probe(struct platform_device *pdev) +{ + struct max77686_dev *iodev = dev_get_drvdata(pdev->dev.parent); + struct max77686_clk *max77686_clks[MAX77686_CLKS_NUM]; + struct clk **clocks; + int i, ret; + + clocks = devm_kzalloc(&pdev->dev, sizeof(struct clk *) + * MAX77686_CLKS_NUM, GFP_KERNEL); + if (!clocks) + return -ENOMEM; + + for (i = 0; i < MAX77686_CLKS_NUM; i++) { + max77686_clks[i] = devm_kzalloc(&pdev->dev, + sizeof(struct max77686_clk), GFP_KERNEL); + if (!max77686_clks[i]) + return -ENOMEM; + } + + for (i = 0; i < MAX77686_CLKS_NUM; i++) { + max77686_clks[i]->iodev = iodev; + max77686_clks[i]->mask = 1 << i; + max77686_clks[i]->hw.init = &max77686_clks_init[i]; + + clocks[i] = max77686_clk_register(&pdev->dev, max77686_clks[i]); + if (IS_ERR(clocks[i])) { + ret = PTR_ERR(clocks[i]); + dev_err(&pdev->dev, "failed to register %s\n", + max77686_clks[i]->hw.init->name); + goto err_clocks; + } + } + + platform_set_drvdata(pdev, clocks); + + if (iodev->dev->of_node) { + struct clk_onecell_data *of_data; + + of_data = devm_kzalloc(&pdev->dev, + sizeof(*of_data), GFP_KERNEL); + if (!of_data) { + ret = -ENOMEM; + goto err_clocks; + } + + of_data->clks = clocks; + of_data->clk_num = MAX77686_CLKS_NUM; + ret = of_clk_add_provider(iodev->dev->of_node, + of_clk_src_onecell_get, of_data); + if (ret) { + dev_err(&pdev->dev, "failed to register OF clock provider\n"); + goto err_clocks; + } + } + + return 0; + +err_clocks: + for (--i; i >= 0; --i) { + clkdev_drop(max77686_clks[i]->lookup); + clk_unregister(max77686_clks[i]->hw.clk); + } + + return ret; +} + +static int max77686_clk_remove(struct platform_device *pdev) +{ + struct max77686_dev *iodev = dev_get_drvdata(pdev->dev.parent); + struct clk **clocks = platform_get_drvdata(pdev); + int i; + + if (iodev->dev->of_node) + of_clk_del_provider(iodev->dev->of_node); + + for (i = 0; i < MAX77686_CLKS_NUM; i++) { + struct clk_hw *hw = __clk_get_hw(clocks[i]); + struct max77686_clk *max77686 = to_max77686_clk(hw); + + clkdev_drop(max77686->lookup); + clk_unregister(clocks[i]); + } + return 0; +} + +static const struct platform_device_id max77686_clk_id[] = { + { "max77686-clk", 0}, + { }, +}; +MODULE_DEVICE_TABLE(platform, max77686_clk_id); + +static struct platform_driver max77686_clk_driver = { + .driver = { + .name = "max77686-clk", + .owner = THIS_MODULE, + }, + .probe = max77686_clk_probe, + .remove = max77686_clk_remove, + .id_table = max77686_clk_id, +}; + +static int __init max77686_clk_init(void) +{ + return platform_driver_register(&max77686_clk_driver); +} +subsys_initcall(max77686_clk_init); + +static void __init max77686_clk_cleanup(void) +{ + platform_driver_unregister(&max77686_clk_driver); +} +module_exit(max77686_clk_cleanup); + +MODULE_DESCRIPTION("MAXIM 77686 Clock Driver"); +MODULE_AUTHOR("Jonghwa Lee <jonghwa3.lee@samsung.com>"); +MODULE_LICENSE("GPL"); |
