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Diffstat (limited to '')
| -rw-r--r-- | drivers/clk/clk-max77686.c | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/drivers/clk/clk-max77686.c b/drivers/clk/clk-max77686.c new file mode 100644 index 000000000..eb953d3b0 --- /dev/null +++ b/drivers/clk/clk-max77686.c @@ -0,0 +1,323 @@ +/* + * clk-max77686.c - Clock driver for Maxim 77686/MAX77802 + * + * 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/module.h> +#include <linux/platform_device.h> +#include <linux/mfd/max77620.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> +#include <linux/of.h> +#include <linux/regmap.h> + +#include <dt-bindings/clock/maxim,max77686.h> +#include <dt-bindings/clock/maxim,max77802.h> +#include <dt-bindings/clock/maxim,max77620.h> + +#define MAX77802_CLOCK_LOW_JITTER_SHIFT 0x3 + +enum max77686_chip_name { + CHIP_MAX77686, + CHIP_MAX77802, + CHIP_MAX77620, +}; + +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 max77686_clk_init_data *max_clk_data; + size_t num_clks; +}; + +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 const struct +max77686_hw_clk_info max77620_hw_clks_info[MAX77620_CLKS_NUM] = { + [MAX77620_CLK_32K_OUT0] = { + .name = "32khz_out0", + .clk_reg = MAX77620_REG_CNFG1_32K, + .clk_enable_mask = MAX77620_CNFG1_32K_OUT0_EN, + }, +}; + +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 struct clk_hw * +of_clk_max77686_get(struct of_phandle_args *clkspec, void *data) +{ + struct max77686_clk_driver_data *drv_data = data; + unsigned int idx = clkspec->args[0]; + + if (idx >= drv_data->num_clks) { + pr_err("%s: invalid index %u\n", __func__, idx); + return ERR_PTR(-EINVAL); + } + + return &drv_data->max_clk_data[idx].hw; +} + +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; + + case CHIP_MAX77620: + num_clks = MAX77620_CLKS_NUM; + hw_clks = max77620_hw_clks_info; + break; + + default: + dev_err(dev, "Unknown Chip ID\n"); + return -EINVAL; + } + + drv_data->num_clks = num_clks; + 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; + + for (i = 0; i < num_clks; i++) { + struct max77686_clk_init_data *max_clk_data; + 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; + + ret = devm_clk_hw_register(dev, &max_clk_data->hw); + if (ret) { + dev_err(dev, "Failed to clock register: %d\n", ret); + return ret; + } + + ret = clk_hw_register_clkdev(&max_clk_data->hw, + max_clk_data->clk_idata.name, NULL); + if (ret < 0) { + dev_err(dev, "Failed to clkdev register: %d\n", ret); + return ret; + } + } + + if (parent->of_node) { + ret = of_clk_add_hw_provider(parent->of_node, of_clk_max77686_get, + drv_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, }, + { "max77620-clock", .driver_data = CHIP_MAX77620, }, + {}, +}; +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 <jonghwa3.lee@samsung.com>"); +MODULE_LICENSE("GPL"); |