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path: root/drivers/regulator/anatop-regulator.c
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Diffstat (limited to 'drivers/regulator/anatop-regulator.c')
-rw-r--r--drivers/regulator/anatop-regulator.c346
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");