/* * clk-max77686.c - Clock driver for Maxim 77686/MAX77802 * * Copyright (C) 2012 Samsung Electornics * Jonghwa Lee * * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #define MAX77802_CLOCK_LOW_JITTER_SHIFT 0x3 enum max77686_chip_name { CHIP_MAX77686, CHIP_MAX77802, }; struct max77686_hw_clk_info { const char *name; u32 clk_reg; u32 clk_enable_mask; u32 flags; }; struct max77686_clk_init_data { struct regmap *regmap; struct clk_hw hw; struct clk_init_data clk_idata; const struct max77686_hw_clk_info *clk_info; }; struct max77686_clk_driver_data { enum max77686_chip_name chip; struct clk **clks; struct max77686_clk_init_data *max_clk_data; struct clk_onecell_data of_data; }; static const struct max77686_hw_clk_info max77686_hw_clks_info[MAX77686_CLKS_NUM] = { [MAX77686_CLK_AP] = { .name = "32khz_ap", .clk_reg = MAX77686_REG_32KHZ, .clk_enable_mask = BIT(MAX77686_CLK_AP), }, [MAX77686_CLK_CP] = { .name = "32khz_cp", .clk_reg = MAX77686_REG_32KHZ, .clk_enable_mask = BIT(MAX77686_CLK_CP), }, [MAX77686_CLK_PMIC] = { .name = "32khz_pmic", .clk_reg = MAX77686_REG_32KHZ, .clk_enable_mask = BIT(MAX77686_CLK_PMIC), }, }; static const struct max77686_hw_clk_info max77802_hw_clks_info[MAX77802_CLKS_NUM] = { [MAX77802_CLK_32K_AP] = { .name = "32khz_ap", .clk_reg = MAX77802_REG_32KHZ, .clk_enable_mask = BIT(MAX77802_CLK_32K_AP), }, [MAX77802_CLK_32K_CP] = { .name = "32khz_cp", .clk_reg = MAX77802_REG_32KHZ, .clk_enable_mask = BIT(MAX77802_CLK_32K_CP), }, }; static struct max77686_clk_init_data *to_max77686_clk_init_data( struct clk_hw *hw) { return container_of(hw, struct max77686_clk_init_data, hw); } static int max77686_clk_prepare(struct clk_hw *hw) { struct max77686_clk_init_data *max77686 = to_max77686_clk_init_data(hw); return regmap_update_bits(max77686->regmap, max77686->clk_info->clk_reg, max77686->clk_info->clk_enable_mask, max77686->clk_info->clk_enable_mask); } static void max77686_clk_unprepare(struct clk_hw *hw) { struct max77686_clk_init_data *max77686 = to_max77686_clk_init_data(hw); regmap_update_bits(max77686->regmap, max77686->clk_info->clk_reg, max77686->clk_info->clk_enable_mask, ~max77686->clk_info->clk_enable_mask); } static int max77686_clk_is_prepared(struct clk_hw *hw) { struct max77686_clk_init_data *max77686 = to_max77686_clk_init_data(hw); int ret; u32 val; ret = regmap_read(max77686->regmap, max77686->clk_info->clk_reg, &val); if (ret < 0) return -EINVAL; return val & max77686->clk_info->clk_enable_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 int max77686_clk_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct device *parent = dev->parent; const struct platform_device_id *id = platform_get_device_id(pdev); struct max77686_clk_driver_data *drv_data; const struct max77686_hw_clk_info *hw_clks; struct regmap *regmap; int i, ret, num_clks; drv_data = devm_kzalloc(dev, sizeof(*drv_data), GFP_KERNEL); if (!drv_data) return -ENOMEM; regmap = dev_get_regmap(parent, NULL); if (!regmap) { dev_err(dev, "Failed to get rtc regmap\n"); return -ENODEV; } drv_data->chip = id->driver_data; switch (drv_data->chip) { case CHIP_MAX77686: num_clks = MAX77686_CLKS_NUM; hw_clks = max77686_hw_clks_info; break; case CHIP_MAX77802: num_clks = MAX77802_CLKS_NUM; hw_clks = max77802_hw_clks_info; break; default: dev_err(dev, "Unknown Chip ID\n"); return -EINVAL; } drv_data->max_clk_data = devm_kcalloc(dev, num_clks, sizeof(*drv_data->max_clk_data), GFP_KERNEL); if (!drv_data->max_clk_data) return -ENOMEM; drv_data->clks = devm_kcalloc(dev, num_clks, sizeof(*drv_data->clks), GFP_KERNEL); if (!drv_data->clks) return -ENOMEM; for (i = 0; i < num_clks; i++) { struct max77686_clk_init_data *max_clk_data; struct clk *clk; const char *clk_name; max_clk_data = &drv_data->max_clk_data[i]; max_clk_data->regmap = regmap; max_clk_data->clk_info = &hw_clks[i]; max_clk_data->clk_idata.flags = hw_clks[i].flags; max_clk_data->clk_idata.ops = &max77686_clk_ops; if (parent->of_node && !of_property_read_string_index(parent->of_node, "clock-output-names", i, &clk_name)) max_clk_data->clk_idata.name = clk_name; else max_clk_data->clk_idata.name = hw_clks[i].name; max_clk_data->hw.init = &max_clk_data->clk_idata; clk = devm_clk_register(dev, &max_clk_data->hw); if (IS_ERR(clk)) { ret = PTR_ERR(clk); dev_err(dev, "Failed to clock register: %d\n", ret); return ret; } ret = clk_register_clkdev(clk, max_clk_data->clk_idata.name, NULL); if (ret < 0) { dev_err(dev, "Failed to clkdev register: %d\n", ret); return ret; } drv_data->clks[i] = clk; } platform_set_drvdata(pdev, drv_data); if (parent->of_node) { drv_data->of_data.clks = drv_data->clks; drv_data->of_data.clk_num = num_clks; ret = of_clk_add_provider(parent->of_node, of_clk_src_onecell_get, &drv_data->of_data); if (ret < 0) { dev_err(dev, "Failed to register OF clock provider: %d\n", ret); return ret; } } /* MAX77802: Enable low-jitter mode on the 32khz clocks. */ if (drv_data->chip == CHIP_MAX77802) { ret = regmap_update_bits(regmap, MAX77802_REG_32KHZ, 1 << MAX77802_CLOCK_LOW_JITTER_SHIFT, 1 << MAX77802_CLOCK_LOW_JITTER_SHIFT); if (ret < 0) { dev_err(dev, "Failed to config low-jitter: %d\n", ret); goto remove_of_clk_provider; } } return 0; remove_of_clk_provider: if (parent->of_node) of_clk_del_provider(parent->of_node); return ret; } static int max77686_clk_remove(struct platform_device *pdev) { struct device *parent = pdev->dev.parent; if (parent->of_node) of_clk_del_provider(parent->of_node); return 0; } static const struct platform_device_id max77686_clk_id[] = { { "max77686-clk", .driver_data = CHIP_MAX77686, }, { "max77802-clk", .driver_data = CHIP_MAX77802, }, {}, }; MODULE_DEVICE_TABLE(platform, max77686_clk_id); static struct platform_driver max77686_clk_driver = { .driver = { .name = "max77686-clk", }, .probe = max77686_clk_probe, .remove = max77686_clk_remove, .id_table = max77686_clk_id, }; module_platform_driver(max77686_clk_driver); MODULE_DESCRIPTION("MAXIM 77686 Clock Driver"); MODULE_AUTHOR("Jonghwa Lee "); MODULE_LICENSE("GPL");