| /* | 
 |  * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved. | 
 |  */ | 
 |  | 
 | /* | 
 |  * 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., | 
 |  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. | 
 |  */ | 
 |  | 
 | #include <linux/slab.h> | 
 | #include <linux/device.h> | 
 | #include <linux/module.h> | 
 | #include <linux/mfd/syscon.h> | 
 | #include <linux/err.h> | 
 | #include <linux/io.h> | 
 | #include <linux/platform_device.h> | 
 | #include <linux/of.h> | 
 | #include <linux/of_address.h> | 
 | #include <linux/regmap.h> | 
 | #include <linux/regulator/driver.h> | 
 | #include <linux/regulator/of_regulator.h> | 
 |  | 
 | #define LDO_RAMP_UP_UNIT_IN_CYCLES      64 /* 64 cycles per step */ | 
 | #define LDO_RAMP_UP_FREQ_IN_MHZ         24 /* cycle based on 24M OSC */ | 
 |  | 
 | #define LDO_POWER_GATE			0x00 | 
 | #define LDO_FET_FULL_ON			0x1f | 
 |  | 
 | struct anatop_regulator { | 
 | 	const char *name; | 
 | 	u32 control_reg; | 
 | 	struct regmap *anatop; | 
 | 	int vol_bit_shift; | 
 | 	int vol_bit_width; | 
 | 	u32 delay_reg; | 
 | 	int delay_bit_shift; | 
 | 	int delay_bit_width; | 
 | 	int min_bit_val; | 
 | 	int min_voltage; | 
 | 	int max_voltage; | 
 | 	struct regulator_desc rdesc; | 
 | 	struct regulator_init_data *initdata; | 
 | 	bool bypass; | 
 | 	int sel; | 
 | }; | 
 |  | 
 | static int anatop_regmap_set_voltage_time_sel(struct regulator_dev *reg, | 
 | 	unsigned int old_sel, | 
 | 	unsigned int new_sel) | 
 | { | 
 | 	struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg); | 
 | 	u32 val; | 
 | 	int ret = 0; | 
 |  | 
 | 	/* check whether need to care about LDO ramp up speed */ | 
 | 	if (anatop_reg->delay_bit_width && new_sel > old_sel) { | 
 | 		/* | 
 | 		 * the delay for LDO ramp up time is | 
 | 		 * based on the register setting, we need | 
 | 		 * to calculate how many steps LDO need to | 
 | 		 * ramp up, and how much delay needed. (us) | 
 | 		 */ | 
 | 		regmap_read(anatop_reg->anatop, anatop_reg->delay_reg, &val); | 
 | 		val = (val >> anatop_reg->delay_bit_shift) & | 
 | 			((1 << anatop_reg->delay_bit_width) - 1); | 
 | 		ret = (new_sel - old_sel) * (LDO_RAMP_UP_UNIT_IN_CYCLES << | 
 | 			val) / LDO_RAMP_UP_FREQ_IN_MHZ + 1; | 
 | 	} | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int anatop_regmap_enable(struct regulator_dev *reg) | 
 | { | 
 | 	struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg); | 
 | 	int sel; | 
 |  | 
 | 	sel = anatop_reg->bypass ? LDO_FET_FULL_ON : anatop_reg->sel; | 
 | 	return regulator_set_voltage_sel_regmap(reg, sel); | 
 | } | 
 |  | 
 | static int anatop_regmap_disable(struct regulator_dev *reg) | 
 | { | 
 | 	return regulator_set_voltage_sel_regmap(reg, LDO_POWER_GATE); | 
 | } | 
 |  | 
 | static int anatop_regmap_is_enabled(struct regulator_dev *reg) | 
 | { | 
 | 	return regulator_get_voltage_sel_regmap(reg) != LDO_POWER_GATE; | 
 | } | 
 |  | 
 | static int anatop_regmap_core_set_voltage_sel(struct regulator_dev *reg, | 
 | 					      unsigned selector) | 
 | { | 
 | 	struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg); | 
 | 	int ret; | 
 |  | 
 | 	if (anatop_reg->bypass || !anatop_regmap_is_enabled(reg)) { | 
 | 		anatop_reg->sel = selector; | 
 | 		return 0; | 
 | 	} | 
 |  | 
 | 	ret = regulator_set_voltage_sel_regmap(reg, selector); | 
 | 	if (!ret) | 
 | 		anatop_reg->sel = selector; | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int anatop_regmap_core_get_voltage_sel(struct regulator_dev *reg) | 
 | { | 
 | 	struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg); | 
 |  | 
 | 	if (anatop_reg->bypass || !anatop_regmap_is_enabled(reg)) | 
 | 		return anatop_reg->sel; | 
 |  | 
 | 	return regulator_get_voltage_sel_regmap(reg); | 
 | } | 
 |  | 
 | static int anatop_regmap_get_bypass(struct regulator_dev *reg, bool *enable) | 
 | { | 
 | 	struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg); | 
 | 	int sel; | 
 |  | 
 | 	sel = regulator_get_voltage_sel_regmap(reg); | 
 | 	if (sel == LDO_FET_FULL_ON) | 
 | 		WARN_ON(!anatop_reg->bypass); | 
 | 	else if (sel != LDO_POWER_GATE) | 
 | 		WARN_ON(anatop_reg->bypass); | 
 |  | 
 | 	*enable = anatop_reg->bypass; | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int anatop_regmap_set_bypass(struct regulator_dev *reg, bool enable) | 
 | { | 
 | 	struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg); | 
 | 	int sel; | 
 |  | 
 | 	if (enable == anatop_reg->bypass) | 
 | 		return 0; | 
 |  | 
 | 	sel = enable ? LDO_FET_FULL_ON : anatop_reg->sel; | 
 | 	anatop_reg->bypass = enable; | 
 |  | 
 | 	return regulator_set_voltage_sel_regmap(reg, sel); | 
 | } | 
 |  | 
 | static struct regulator_ops anatop_rops = { | 
 | 	.set_voltage_sel = regulator_set_voltage_sel_regmap, | 
 | 	.get_voltage_sel = regulator_get_voltage_sel_regmap, | 
 | 	.list_voltage = regulator_list_voltage_linear, | 
 | 	.map_voltage = regulator_map_voltage_linear, | 
 | }; | 
 |  | 
 | static struct regulator_ops anatop_core_rops = { | 
 | 	.enable = anatop_regmap_enable, | 
 | 	.disable = anatop_regmap_disable, | 
 | 	.is_enabled = anatop_regmap_is_enabled, | 
 | 	.set_voltage_sel = anatop_regmap_core_set_voltage_sel, | 
 | 	.set_voltage_time_sel = anatop_regmap_set_voltage_time_sel, | 
 | 	.get_voltage_sel = anatop_regmap_core_get_voltage_sel, | 
 | 	.list_voltage = regulator_list_voltage_linear, | 
 | 	.map_voltage = regulator_map_voltage_linear, | 
 | 	.get_bypass = anatop_regmap_get_bypass, | 
 | 	.set_bypass = anatop_regmap_set_bypass, | 
 | }; | 
 |  | 
 | static int anatop_regulator_probe(struct platform_device *pdev) | 
 | { | 
 | 	struct device *dev = &pdev->dev; | 
 | 	struct device_node *np = dev->of_node; | 
 | 	struct device_node *anatop_np; | 
 | 	struct regulator_desc *rdesc; | 
 | 	struct regulator_dev *rdev; | 
 | 	struct anatop_regulator *sreg; | 
 | 	struct regulator_init_data *initdata; | 
 | 	struct regulator_config config = { }; | 
 | 	int ret = 0; | 
 | 	u32 val; | 
 |  | 
 | 	sreg = devm_kzalloc(dev, sizeof(*sreg), GFP_KERNEL); | 
 | 	if (!sreg) | 
 | 		return -ENOMEM; | 
 | 	sreg->name = of_get_property(np, "regulator-name", NULL); | 
 | 	rdesc = &sreg->rdesc; | 
 | 	rdesc->name = sreg->name; | 
 | 	rdesc->type = REGULATOR_VOLTAGE; | 
 | 	rdesc->owner = THIS_MODULE; | 
 |  | 
 | 	initdata = of_get_regulator_init_data(dev, np, rdesc); | 
 | 	sreg->initdata = initdata; | 
 |  | 
 | 	anatop_np = of_get_parent(np); | 
 | 	if (!anatop_np) | 
 | 		return -ENODEV; | 
 | 	sreg->anatop = syscon_node_to_regmap(anatop_np); | 
 | 	of_node_put(anatop_np); | 
 | 	if (IS_ERR(sreg->anatop)) | 
 | 		return PTR_ERR(sreg->anatop); | 
 |  | 
 | 	ret = of_property_read_u32(np, "anatop-reg-offset", | 
 | 				   &sreg->control_reg); | 
 | 	if (ret) { | 
 | 		dev_err(dev, "no anatop-reg-offset property set\n"); | 
 | 		return ret; | 
 | 	} | 
 | 	ret = of_property_read_u32(np, "anatop-vol-bit-width", | 
 | 				   &sreg->vol_bit_width); | 
 | 	if (ret) { | 
 | 		dev_err(dev, "no anatop-vol-bit-width property set\n"); | 
 | 		return ret; | 
 | 	} | 
 | 	ret = of_property_read_u32(np, "anatop-vol-bit-shift", | 
 | 				   &sreg->vol_bit_shift); | 
 | 	if (ret) { | 
 | 		dev_err(dev, "no anatop-vol-bit-shift property set\n"); | 
 | 		return ret; | 
 | 	} | 
 | 	ret = of_property_read_u32(np, "anatop-min-bit-val", | 
 | 				   &sreg->min_bit_val); | 
 | 	if (ret) { | 
 | 		dev_err(dev, "no anatop-min-bit-val property set\n"); | 
 | 		return ret; | 
 | 	} | 
 | 	ret = of_property_read_u32(np, "anatop-min-voltage", | 
 | 				   &sreg->min_voltage); | 
 | 	if (ret) { | 
 | 		dev_err(dev, "no anatop-min-voltage property set\n"); | 
 | 		return ret; | 
 | 	} | 
 | 	ret = of_property_read_u32(np, "anatop-max-voltage", | 
 | 				   &sreg->max_voltage); | 
 | 	if (ret) { | 
 | 		dev_err(dev, "no anatop-max-voltage property set\n"); | 
 | 		return ret; | 
 | 	} | 
 |  | 
 | 	/* read LDO ramp up setting, only for core reg */ | 
 | 	of_property_read_u32(np, "anatop-delay-reg-offset", | 
 | 			     &sreg->delay_reg); | 
 | 	of_property_read_u32(np, "anatop-delay-bit-width", | 
 | 			     &sreg->delay_bit_width); | 
 | 	of_property_read_u32(np, "anatop-delay-bit-shift", | 
 | 			     &sreg->delay_bit_shift); | 
 |  | 
 | 	rdesc->n_voltages = (sreg->max_voltage - sreg->min_voltage) / 25000 + 1 | 
 | 			    + sreg->min_bit_val; | 
 | 	rdesc->min_uV = sreg->min_voltage; | 
 | 	rdesc->uV_step = 25000; | 
 | 	rdesc->linear_min_sel = sreg->min_bit_val; | 
 | 	rdesc->vsel_reg = sreg->control_reg; | 
 | 	rdesc->vsel_mask = ((1 << sreg->vol_bit_width) - 1) << | 
 | 			   sreg->vol_bit_shift; | 
 |  | 
 | 	config.dev = &pdev->dev; | 
 | 	config.init_data = initdata; | 
 | 	config.driver_data = sreg; | 
 | 	config.of_node = pdev->dev.of_node; | 
 | 	config.regmap = sreg->anatop; | 
 |  | 
 | 	/* Only core regulators have the ramp up delay configuration. */ | 
 | 	if (sreg->control_reg && sreg->delay_bit_width) { | 
 | 		rdesc->ops = &anatop_core_rops; | 
 |  | 
 | 		ret = regmap_read(config.regmap, rdesc->vsel_reg, &val); | 
 | 		if (ret) { | 
 | 			dev_err(dev, "failed to read initial state\n"); | 
 | 			return ret; | 
 | 		} | 
 |  | 
 | 		sreg->sel = (val & rdesc->vsel_mask) >> sreg->vol_bit_shift; | 
 | 		if (sreg->sel == LDO_FET_FULL_ON) { | 
 | 			sreg->sel = 0; | 
 | 			sreg->bypass = true; | 
 | 		} | 
 |  | 
 | 		/* | 
 | 		 * In case vddpu was disabled by the bootloader, we need to set | 
 | 		 * a sane default until imx6-cpufreq was probed and changes the | 
 | 		 * voltage to the correct value. In this case we set 1.25V. | 
 | 		 */ | 
 | 		if (!sreg->sel && !strcmp(sreg->name, "vddpu")) | 
 | 			sreg->sel = 22; | 
 |  | 
 | 		if (!sreg->sel) { | 
 | 			dev_err(&pdev->dev, "Failed to read a valid default voltage selector.\n"); | 
 | 			return -EINVAL; | 
 | 		} | 
 | 	} else { | 
 | 		rdesc->ops = &anatop_rops; | 
 | 	} | 
 |  | 
 | 	/* register regulator */ | 
 | 	rdev = devm_regulator_register(dev, rdesc, &config); | 
 | 	if (IS_ERR(rdev)) { | 
 | 		dev_err(dev, "failed to register %s\n", | 
 | 			rdesc->name); | 
 | 		return PTR_ERR(rdev); | 
 | 	} | 
 |  | 
 | 	platform_set_drvdata(pdev, rdev); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static const struct of_device_id of_anatop_regulator_match_tbl[] = { | 
 | 	{ .compatible = "fsl,anatop-regulator", }, | 
 | 	{ /* end */ } | 
 | }; | 
 |  | 
 | static struct platform_driver anatop_regulator_driver = { | 
 | 	.driver = { | 
 | 		.name	= "anatop_regulator", | 
 | 		.of_match_table = of_anatop_regulator_match_tbl, | 
 | 	}, | 
 | 	.probe	= anatop_regulator_probe, | 
 | }; | 
 |  | 
 | static int __init anatop_regulator_init(void) | 
 | { | 
 | 	return platform_driver_register(&anatop_regulator_driver); | 
 | } | 
 | postcore_initcall(anatop_regulator_init); | 
 |  | 
 | static void __exit anatop_regulator_exit(void) | 
 | { | 
 | 	platform_driver_unregister(&anatop_regulator_driver); | 
 | } | 
 | module_exit(anatop_regulator_exit); | 
 |  | 
 | MODULE_AUTHOR("Nancy Chen <Nancy.Chen@freescale.com>"); | 
 | MODULE_AUTHOR("Ying-Chun Liu (PaulLiu) <paul.liu@linaro.org>"); | 
 | MODULE_DESCRIPTION("ANATOP Regulator driver"); | 
 | MODULE_LICENSE("GPL v2"); | 
 | MODULE_ALIAS("platform:anatop_regulator"); |