regulator: Add Anatop regulator driver

Anatop is an integrated regulator inside i.MX6 SoC.
There are 3 digital regulators which controls PU, CORE (ARM), and SOC.
And 3 analog regulators which controls 1P1, 2P5, 3P0 (USB).
This patch adds the Anatop regulator driver.

Signed-off-by: Nancy Chen <Nancy.Chen@freescale.com>
Signed-off-by: Ying-Chun Liu (PaulLiu) <paul.liu@linaro.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 241 insertions, 0 deletions

diff --git a/drivers/regulator/anatop-regulator.c b/drivers/regulator/anatop-regulator.c
new file mode 100644
index 000000000000..17499a55113d
--- /dev/null
+++ b/drivers/regulator/anatop-regulator.c
@@ -0,0 +1,241 @@
+/*
+ * 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/err.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/mfd/anatop.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/of_regulator.h>
+
+struct anatop_regulator {
+        const char *name;
+        u32 control_reg;
+        struct anatop *mfd;
+        int vol_bit_shift;
+        int vol_bit_width;
+        int min_bit_val;
+        int min_voltage;
+        int max_voltage;
+        struct regulator_desc rdesc;
+        struct regulator_init_data *initdata;
+};
+
+static int anatop_set_voltage(struct regulator_dev *reg, int min_uV,
+                                  int max_uV, unsigned *selector)
+{
+        struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
+        u32 val, sel;
+        int uv;
+
+        uv = min_uV;
+        dev_dbg(&reg->dev, "%s: uv %d, min %d, max %d\n", __func__,
+                uv, anatop_reg->min_voltage,
+                anatop_reg->max_voltage);
+
+        if (uv < anatop_reg->min_voltage) {
+                if (max_uV > anatop_reg->min_voltage)
+                        uv = anatop_reg->min_voltage;
+                else
+                        return -EINVAL;
+        }
+
+        if (!anatop_reg->control_reg)
+                return -ENOTSUPP;
+
+        sel = DIV_ROUND_UP(uv - anatop_reg->min_voltage, 25000);
+        if (sel * 25000 + anatop_reg->min_voltage > anatop_reg->max_voltage)
+                return -EINVAL;
+        val = anatop_reg->min_bit_val + sel;
+        *selector = sel;
+        dev_dbg(&reg->dev, "%s: calculated val %d\n", __func__, val);
+        anatop_set_bits(anatop_reg->mfd,
+                        anatop_reg->control_reg,
+                        anatop_reg->vol_bit_shift,
+                        anatop_reg->vol_bit_width,
+                        val);
+
+        return 0;
+}
+
+static int anatop_get_voltage_sel(struct regulator_dev *reg)
+{
+        struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
+        u32 val;
+
+        if (!anatop_reg->control_reg)
+                return -ENOTSUPP;
+
+        val = anatop_get_bits(anatop_reg->mfd,
+                              anatop_reg->control_reg,
+                              anatop_reg->vol_bit_shift,
+                              anatop_reg->vol_bit_width);
+
+        return val - anatop_reg->min_bit_val;
+}
+
+static int anatop_list_voltage(struct regulator_dev *reg, unsigned selector)
+{
+        struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
+        int uv;
+
+        uv = anatop_reg->min_voltage + selector * 25000;
+        dev_dbg(&reg->dev, "vddio = %d, selector = %u\n", uv, selector);
+
+        return uv;
+}
+
+static struct regulator_ops anatop_rops = {
+        .set_voltage     = anatop_set_voltage,
+        .get_voltage_sel = anatop_get_voltage_sel,
+        .list_voltage    = anatop_list_voltage,
+};
+
+static int __devinit anatop_regulator_probe(struct platform_device *pdev)
+{
+        struct device *dev = &pdev->dev;
+        struct device_node *np = dev->of_node;
+        struct regulator_desc *rdesc;
+        struct regulator_dev *rdev;
+        struct anatop_regulator *sreg;
+        struct regulator_init_data *initdata;
+        struct anatop *anatopmfd = dev_get_drvdata(pdev->dev.parent);
+        int ret = 0;
+
+        initdata = of_get_regulator_init_data(dev, np);
+        sreg = devm_kzalloc(dev, sizeof(*sreg), GFP_KERNEL);
+        if (!sreg)
+                return -ENOMEM;
+        sreg->initdata = initdata;
+        sreg->name = kstrdup(of_get_property(np, "regulator-name", NULL),
+                             GFP_KERNEL);
+        rdesc = &sreg->rdesc;
+        memset(rdesc, 0, sizeof(*rdesc));
+        rdesc->name = sreg->name;
+        rdesc->ops = &anatop_rops;
+        rdesc->type = REGULATOR_VOLTAGE;
+        rdesc->owner = THIS_MODULE;
+        sreg->mfd = anatopmfd;
+        ret = of_property_read_u32(np, "reg", &sreg->control_reg);
+        if (ret) {
+                dev_err(dev, "no reg property set\n");
+                goto anatop_probe_end;
+        }
+        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");
+                goto anatop_probe_end;
+        }
+        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");
+                goto anatop_probe_end;
+        }
+        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");
+                goto anatop_probe_end;
+        }
+        ret = of_property_read_u32(np, "anatop-min-voltage",
+                                   &sreg->min_voltage);
+        if (ret) {
+                dev_err(dev, "no anatop-min-voltage property set\n");
+                goto anatop_probe_end;
+        }
+        ret = of_property_read_u32(np, "anatop-max-voltage",
+                                   &sreg->max_voltage);
+        if (ret) {
+                dev_err(dev, "no anatop-max-voltage property set\n");
+                goto anatop_probe_end;
+        }
+
+        rdesc->n_voltages = (sreg->max_voltage - sreg->min_voltage)
+                / 25000 + 1;
+
+        /* register regulator */
+        rdev = regulator_register(rdesc, dev,
+                                  initdata, sreg, pdev->dev.of_node);
+        if (IS_ERR(rdev)) {
+                dev_err(dev, "failed to register %s\n",
+                        rdesc->name);
+                ret = PTR_ERR(rdev);
+                goto anatop_probe_end;
+        }
+
+        platform_set_drvdata(pdev, rdev);
+
+anatop_probe_end:
+        if (ret)
+                kfree(sreg->name);
+
+        return ret;
+}
+
+static int __devexit anatop_regulator_remove(struct platform_device *pdev)
+{
+        struct regulator_dev *rdev = platform_get_drvdata(pdev);
+        struct anatop_regulator *sreg = rdev_get_drvdata(rdev);
+        const char *name = sreg->name;
+
+        regulator_unregister(rdev);
+        kfree(name);
+
+        return 0;
+}
+
+static struct of_device_id __devinitdata of_anatop_regulator_match_tbl[] = {
+        { .compatible = "fsl,anatop-regulator", },
+        { /* end */ }
+};
+
+static struct platform_driver anatop_regulator = {
+        .driver = {
+                .name   = "anatop_regulator",
+                .owner  = THIS_MODULE,
+                .of_match_table = of_anatop_regulator_match_tbl,
+        },
+        .probe  = anatop_regulator_probe,
+        .remove = anatop_regulator_remove,
+};
+
+static int __init anatop_regulator_init(void)
+{
+        return platform_driver_register(&anatop_regulator);
+}
+postcore_initcall(anatop_regulator_init);
+
+static void __exit anatop_regulator_exit(void)
+{
+        platform_driver_unregister(&anatop_regulator);
+}
+module_exit(anatop_regulator_exit);
+
+MODULE_AUTHOR("Nancy Chen <Nancy.Chen@freescale.com>, "
+              "Ying-Chun Liu (PaulLiu) <paul.liu@linaro.org>");
+MODULE_DESCRIPTION("ANATOP Regulator driver");
+MODULE_LICENSE("GPL v2");