2009-04-23 18:11:19

by Robert Jarzmik

[permalink] [raw]
Subject: [PATCH v2] Maxim 1586 regulator driver

The Maxim 1586 regulator is a voltage regulator with 2
voltage outputs, specially suitable for Marvell PXA
chips. One output is in the range of required VCC_CORE by
the PXA27x chips, the other in the VCC_USIM required as well
by PXA27x chips.

The chip is controlled through the I2C bus.

Signed-off-by: Robert Jarzmik <[email protected]>
---
drivers/regulator/Kconfig | 8 ++
drivers/regulator/Makefile | 1 +
drivers/regulator/max1586.c | 249 +++++++++++++++++++++++++++++++++++++
include/linux/regulator/max1586.h | 52 ++++++++
4 files changed, 310 insertions(+), 0 deletions(-)
create mode 100644 drivers/regulator/max1586.c
create mode 100644 include/linux/regulator/max1586.h

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index e58c0ce..72f0ae1 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -56,6 +56,14 @@ config REGULATOR_BQ24022
charging select between 100 mA and 500 mA charging current
limit.

+config REGULATOR_MAX1586
+ tristate "Maxim 1586/1587 voltage regulator"
+ default n
+ help
+ This driver controls a Maxim 1586 or 1587 voltage output
+ regulator via I2C bus. The provided regulator is suitable
+ for PXA27x chips to control VCC_CORE and VCC_USIM voltages.
+
config REGULATOR_TWL4030
bool "TI TWL4030/TWL5030/TPS695x0 PMIC"
depends on TWL4030_CORE
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index bac133a..1d7de87 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_REGULATOR_FIXED_VOLTAGE) += fixed.o
obj-$(CONFIG_REGULATOR_VIRTUAL_CONSUMER) += virtual.o

obj-$(CONFIG_REGULATOR_BQ24022) += bq24022.o
+obj-$(CONFIG_REGULATOR_MAX1586) += max1586.o
obj-$(CONFIG_REGULATOR_TWL4030) += twl4030-regulator.o
obj-$(CONFIG_REGULATOR_WM8350) += wm8350-regulator.o
obj-$(CONFIG_REGULATOR_WM8400) += wm8400-regulator.o
diff --git a/drivers/regulator/max1586.c b/drivers/regulator/max1586.c
new file mode 100644
index 0000000..bbbb55f
--- /dev/null
+++ b/drivers/regulator/max1586.c
@@ -0,0 +1,249 @@
+/*
+ * max1586.c -- Voltage and current regulation for the Maxim 1586
+ *
+ * Copyright (C) 2008 Robert Jarzmik
+ *
+ * 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/module.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/max1586.h>
+
+#define MAX1586_V3_MAX_VSEL 31
+#define MAX1586_V6_MAX_VSEL 3
+
+#define MAX1586_V3_MIN_UV 700000
+#define MAX1586_V3_MAX_UV 1475000
+#define MAX1586_V3_STEP_UV 25000
+
+#define MAX1586_V6_MIN_UV 0
+#define MAX1586_V6_MAX_UV 3000000
+
+#define I2C_V3_SELECT (0 << 5)
+#define I2C_V6_SELECT (1 << 5)
+
+/*
+ * V3 voltage
+ * On I2C bus, sending a "x" byte to the max1586 means :
+ * set V3 to 0.700V + (x & 0x1f) * 0.025V
+ */
+static int max1586_v3_calc_voltage(unsigned selector)
+{
+ return MAX1586_V3_MIN_UV + (MAX1586_V3_STEP_UV * selector);
+}
+
+static int max1586_v3_set(struct regulator_dev *rdev, int min_uV, int max_uV)
+{
+ struct i2c_client *client = rdev_get_drvdata(rdev);
+ unsigned selector;
+ u8 v3_prog;
+
+ if (min_uV < MAX1586_V3_MIN_UV || min_uV > MAX1586_V3_MAX_UV)
+ return -EINVAL;
+ if (max_uV < MAX1586_V3_MIN_UV || max_uV > MAX1586_V3_MAX_UV)
+ return -EINVAL;
+
+ selector = (min_uV - MAX1586_V3_MIN_UV) / MAX1586_V3_STEP_UV;
+ if (max1586_v3_calc_voltage(selector) > max_uV)
+ return -EINVAL;
+
+ dev_dbg(&client->dev, "changing voltage v3 to %dmv\n",
+ max1586_v3_calc_voltage(selector) / 1000);
+
+ v3_prog = I2C_V3_SELECT | (u8) selector;
+ return i2c_smbus_write_byte(client, v3_prog);
+}
+
+static int max1586_v3_list(struct regulator_dev *rdev, unsigned selector)
+{
+ if (selector > MAX1586_V3_MAX_VSEL)
+ return -EINVAL;
+ return max1586_v3_calc_voltage(selector);
+}
+
+/*
+ * V6 voltage
+ * On I2C bus, sending a "x" byte to the max1586 means :
+ * set V6 to either 0V, 1.8V, 2.5V, 3V depending on (x & 0x3)
+ * As regulator framework doesn't accept voltages to be 0V, we use 1uV.
+ */
+static int max1586_v6_calc_voltage(unsigned selector)
+{
+ static int voltages_uv[] = { 1, 1800000, 2500000, 3000000 };
+
+ return voltages_uv[selector];
+}
+
+static int max1586_v6_set(struct regulator_dev *rdev, int min_uV, int max_uV)
+{
+ struct i2c_client *client = rdev_get_drvdata(rdev);
+ unsigned selector;
+ u8 v6_prog;
+
+ if (min_uV < MAX1586_V6_MIN_UV || min_uV > MAX1586_V6_MAX_UV)
+ return -EINVAL;
+ if (max_uV < MAX1586_V6_MIN_UV || max_uV > MAX1586_V6_MAX_UV)
+ return -EINVAL;
+
+ if (min_uV >= 3000000)
+ selector = 3;
+ if (min_uV < 3000000)
+ selector = 2;
+ if (min_uV < 2500000)
+ selector = 1;
+ if (min_uV < 1800000)
+ selector = 0;
+
+ if (max1586_v6_calc_voltage(selector) > max_uV)
+ return -EINVAL;
+
+ dev_dbg(&client->dev, "changing voltage v6 to %dmv\n",
+ max1586_v6_calc_voltage(selector) / 1000);
+
+ v6_prog = I2C_V6_SELECT | (u8) selector;
+ return i2c_smbus_write_byte(client, v6_prog);
+}
+
+static int max1586_v6_list(struct regulator_dev *rdev, unsigned selector)
+{
+ if (selector > MAX1586_V6_MAX_VSEL)
+ return -EINVAL;
+ return max1586_v6_calc_voltage(selector);
+}
+
+/*
+ * The Maxim 1586 controls V3 and V6 voltages, but offers no way of reading back
+ * the set up value.
+ */
+static struct regulator_ops max1586_v3_ops = {
+ .set_voltage = max1586_v3_set,
+ .list_voltage = max1586_v3_list,
+};
+
+static struct regulator_ops max1586_v6_ops = {
+ .set_voltage = max1586_v6_set,
+ .list_voltage = max1586_v6_list,
+};
+
+static struct regulator_desc max1586_reg[] = {
+ {
+ .name = "Output_V3",
+ .id = MAX1586_V3,
+ .ops = &max1586_v3_ops,
+ .type = REGULATOR_VOLTAGE,
+ .n_voltages = MAX1586_V3_MAX_VSEL + 1,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "Output_V6",
+ .id = MAX1586_V6,
+ .ops = &max1586_v6_ops,
+ .type = REGULATOR_VOLTAGE,
+ .n_voltages = MAX1586_V6_MAX_VSEL + 1,
+ .owner = THIS_MODULE,
+ },
+};
+
+static int max1586_pmic_probe(struct i2c_client *client,
+ const struct i2c_device_id *i2c_id)
+{
+ struct regulator_dev **rdev;
+ struct max1586_platform_data *pdata = client->dev.platform_data;
+ int i, id, ret = 0;
+
+ rdev = kzalloc(sizeof(struct regulator_dev *) * (MAX1586_V6 + 1),
+ GFP_KERNEL);
+ if (!rdev)
+ return -ENOMEM;
+
+ ret = -EINVAL;
+ for (i = 0; i < pdata->num_subdevs && i <= MAX1586_V6; i++) {
+ id = pdata->subdevs[i].id;
+ if (!pdata->subdevs[i].platform_data)
+ continue;
+ if (id < MAX1586_V3 || id > MAX1586_V6) {
+ dev_err(&client->dev, "invalid regulator id %d\n", id);
+ goto err;
+ }
+ rdev[i] = regulator_register(&max1586_reg[id], &client->dev,
+ pdata->subdevs[i].platform_data,
+ client);
+ if (IS_ERR(rdev[i])) {
+ ret = PTR_ERR(rdev[i]);
+ dev_err(&client->dev, "failed to register %s\n",
+ max1586_reg[id].name);
+ goto err;
+ }
+ }
+
+ i2c_set_clientdata(client, rdev);
+ dev_info(&client->dev, "Maxim 1586 regulator driver loaded\n");
+ return 0;
+
+err:
+ while (--i >= 0)
+ regulator_unregister(rdev[i]);
+ kfree(rdev);
+ return ret;
+}
+
+static int max1586_pmic_remove(struct i2c_client *client)
+{
+ struct regulator_dev **rdev = i2c_get_clientdata(client);
+ int i;
+
+ for (i = 0; i <= MAX1586_V6; i++)
+ if (rdev[i])
+ regulator_unregister(rdev[i]);
+ kfree(rdev);
+ i2c_set_clientdata(client, NULL);
+
+ return 0;
+}
+
+static const struct i2c_device_id max1586_id[] = {
+ { "max1586", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, max1586_id);
+
+static struct i2c_driver max1586_pmic_driver = {
+ .probe = max1586_pmic_probe,
+ .remove = max1586_pmic_remove,
+ .driver = {
+ .name = "max1586",
+ },
+ .id_table = max1586_id,
+};
+
+static int __init max1586_pmic_init(void)
+{
+ return i2c_add_driver(&max1586_pmic_driver);
+}
+subsys_initcall(max1586_pmic_init);
+
+static void __exit max1586_pmic_exit(void)
+{
+ i2c_del_driver(&max1586_pmic_driver);
+}
+module_exit(max1586_pmic_exit);
+
+/* Module information */
+MODULE_DESCRIPTION("MAXIM 1586 voltage regulator driver");
+MODULE_AUTHOR("Robert Jarzmik");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/regulator/max1586.h b/include/linux/regulator/max1586.h
new file mode 100644
index 0000000..2056973
--- /dev/null
+++ b/include/linux/regulator/max1586.h
@@ -0,0 +1,52 @@
+/*
+ * max1586.h -- Voltage regulation for the Maxim 1586
+ *
+ * Copyright (C) 2008 Robert Jarzmik
+ *
+ * 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
+ */
+
+#ifndef REGULATOR_MAX1586
+#define REGULATOR_MAX1586
+
+#include <linux/regulator/machine.h>
+
+#define MAX1586_V3 0
+#define MAX1586_V6 1
+
+/**
+ * max1586_subdev_data - regulator data
+ * @id: regulator Id (either MAX1586_V3 or MAX1586_V6)
+ * @name: regulator cute name (example for V3: "vcc_core")
+ * @platform_data: regulator init data (contraints, supplies, ...)
+ */
+struct max1586_subdev_data {
+ int id;
+ char *name;
+ struct regulator_init_data *platform_data;
+};
+
+/**
+ * max1586_platform_data - platform data for max1586
+ * @num_subdevs: number of regultors used (may be 1 or 2)
+ * @subdevs: regulator used
+ * At most, there will be a regulator for V3 and one for V6 voltages.
+ */
+struct max1586_platform_data {
+ int num_subdevs;
+ struct max1586_subdev_data *subdevs;
+};
+
+#endif
--
1.6.2.1


2009-04-23 20:02:51

by Mark Brown

[permalink] [raw]
Subject: Re: [PATCH v2] Maxim 1586 regulator driver

On Thu, Apr 23, 2009 at 08:10:43PM +0200, Robert Jarzmik wrote:

> +/*
> + * max1586.c -- Voltage and current regulation for the Maxim 1586
> + *
> + * Copyright (C) 2008 Robert Jarzmik

You're living in the past here!

> +/*
> + * V6 voltage
> + * On I2C bus, sending a "x" byte to the max1586 means :
> + * set V6 to either 0V, 1.8V, 2.5V, 3V depending on (x & 0x3)
> + * As regulator framework doesn't accept voltages to be 0V, we use 1uV.
> + */

Having seen the regulation constraints you're using on your board I'm
thinking even more that it'd be better to implement enable and disable
operations for the driver. On the other hand, the driver is useful now
and my other comments are all very much nitpicks so from my point of
view:

Acked-by: Mark Brown <[email protected]>

> + dev_dbg(&client->dev, "changing voltage v6 to %dmv\n",
> + max1586_v6_calc_voltage(selector) / 1000);

mv should be mV.

2009-04-27 12:40:39

by Liam Girdwood

[permalink] [raw]
Subject: Re: [PATCH v2] Maxim 1586 regulator driver

On Thu, 2009-04-23 at 20:10 +0200, Robert Jarzmik wrote:
> The Maxim 1586 regulator is a voltage regulator with 2
> voltage outputs, specially suitable for Marvell PXA
> chips. One output is in the range of required VCC_CORE by
> the PXA27x chips, the other in the VCC_USIM required as well
> by PXA27x chips.
>
> The chip is controlled through the I2C bus.
>
> Signed-off-by: Robert Jarzmik <[email protected]>

Applied with dependency on I2C.

Thanks

Liam