diff options
Diffstat (limited to 'drivers/regulator/anatop-regulator.c')
| -rw-r--r-- | drivers/regulator/anatop-regulator.c | 346 |
1 files changed, 346 insertions, 0 deletions
diff --git a/drivers/regulator/anatop-regulator.c b/drivers/regulator/anatop-regulator.c new file mode 100644 index 000000000..738adfa53 --- /dev/null +++ b/drivers/regulator/anatop-regulator.c @@ -0,0 +1,346 @@ +/* + * 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"); |