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authorLinus Walleij <linus.walleij@stericsson.com>2009-09-09 11:31:00 +0200
committerSamuel Ortiz <sameo@linux.intel.com>2009-09-17 09:47:25 +0200
commitd619bc143e311a738113dbbe7792bd032403939f (patch)
treef5a7bebf4058761a223dba7ffc7057d70d17245b /drivers/regulator/ab3100.c
parentrtc: AB3100 RTC support (diff)
downloadlinux-d619bc143e311a738113dbbe7792bd032403939f.tar.xz
linux-d619bc143e311a738113dbbe7792bd032403939f.zip
regulator: AB3100 support
This adds support for the regulators found in the AB3100 Mixed-Signal IC. It further also defines platform data for the ST-Ericsson U300 platform and extends the AB3100 MFD driver so that platform/board data with regulation constraints and an init function can be passed down all the way from the board to the regulators. Signed-off-by: Linus Walleij <linus.walleij@stericsson.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Diffstat (limited to 'drivers/regulator/ab3100.c')
-rw-r--r--drivers/regulator/ab3100.c694
1 files changed, 694 insertions, 0 deletions
diff --git a/drivers/regulator/ab3100.c b/drivers/regulator/ab3100.c
new file mode 100644
index 000000000000..156979d1f41e
--- /dev/null
+++ b/drivers/regulator/ab3100.c
@@ -0,0 +1,694 @@
+/*
+ * drivers/regulator/ab3100.c
+ *
+ * Copyright (C) 2008-2009 ST-Ericsson AB
+ * License terms: GNU General Public License (GPL) version 2
+ * Low-level control of the AB3100 IC Low Dropout (LDO)
+ * regulators, external regulator and buck converter
+ * Author: Mattias Wallin <mattias.wallin@stericsson.com>
+ * Author: Linus Walleij <linus.walleij@stericsson.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/mfd/ab3100.h>
+
+/* LDO registers and some handy masking definitions for AB3100 */
+#define AB3100_LDO_A 0x40
+#define AB3100_LDO_C 0x41
+#define AB3100_LDO_D 0x42
+#define AB3100_LDO_E 0x43
+#define AB3100_LDO_E_SLEEP 0x44
+#define AB3100_LDO_F 0x45
+#define AB3100_LDO_G 0x46
+#define AB3100_LDO_H 0x47
+#define AB3100_LDO_H_SLEEP_MODE 0
+#define AB3100_LDO_H_SLEEP_EN 2
+#define AB3100_LDO_ON 4
+#define AB3100_LDO_H_VSEL_AC 5
+#define AB3100_LDO_K 0x48
+#define AB3100_LDO_EXT 0x49
+#define AB3100_BUCK 0x4A
+#define AB3100_BUCK_SLEEP 0x4B
+#define AB3100_REG_ON_MASK 0x10
+
+/**
+ * struct ab3100_regulator
+ * A struct passed around the individual regulator functions
+ * @platform_device: platform device holding this regulator
+ * @ab3100: handle to the AB3100 parent chip
+ * @plfdata: AB3100 platform data passed in at probe time
+ * @regreg: regulator register number in the AB3100
+ * @fixed_voltage: a fixed voltage for this regulator, if this
+ * 0 the voltages array is used instead.
+ * @typ_voltages: an array of available typical voltages for
+ * this regulator
+ * @voltages_len: length of the array of available voltages
+ */
+struct ab3100_regulator {
+ struct regulator_dev *rdev;
+ struct ab3100 *ab3100;
+ struct ab3100_platform_data *plfdata;
+ u8 regreg;
+ int fixed_voltage;
+ int const *typ_voltages;
+ u8 voltages_len;
+};
+
+/* The order in which registers are initialized */
+static const u8 ab3100_reg_init_order[AB3100_NUM_REGULATORS+2] = {
+ AB3100_LDO_A,
+ AB3100_LDO_C,
+ AB3100_LDO_E,
+ AB3100_LDO_E_SLEEP,
+ AB3100_LDO_F,
+ AB3100_LDO_G,
+ AB3100_LDO_H,
+ AB3100_LDO_K,
+ AB3100_LDO_EXT,
+ AB3100_BUCK,
+ AB3100_BUCK_SLEEP,
+ AB3100_LDO_D,
+};
+
+/* Preset (hardware defined) voltages for these regulators */
+#define LDO_A_VOLTAGE 2750000
+#define LDO_C_VOLTAGE 2650000
+#define LDO_D_VOLTAGE 2650000
+
+static const int const ldo_e_buck_typ_voltages[] = {
+ 1800000,
+ 1400000,
+ 1300000,
+ 1200000,
+ 1100000,
+ 1050000,
+ 900000,
+};
+
+static const int const ldo_f_typ_voltages[] = {
+ 1800000,
+ 1400000,
+ 1300000,
+ 1200000,
+ 1100000,
+ 1050000,
+ 2500000,
+ 2650000,
+};
+
+static const int const ldo_g_typ_voltages[] = {
+ 2850000,
+ 2750000,
+ 1800000,
+ 1500000,
+};
+
+static const int const ldo_h_typ_voltages[] = {
+ 2750000,
+ 1800000,
+ 1500000,
+ 1200000,
+};
+
+static const int const ldo_k_typ_voltages[] = {
+ 2750000,
+ 1800000,
+};
+
+
+/* The regulator devices */
+static struct ab3100_regulator
+ab3100_regulators[AB3100_NUM_REGULATORS] = {
+ {
+ .regreg = AB3100_LDO_A,
+ .fixed_voltage = LDO_A_VOLTAGE,
+ },
+ {
+ .regreg = AB3100_LDO_C,
+ .fixed_voltage = LDO_C_VOLTAGE,
+ },
+ {
+ .regreg = AB3100_LDO_D,
+ .fixed_voltage = LDO_D_VOLTAGE,
+ },
+ {
+ .regreg = AB3100_LDO_E,
+ .typ_voltages = ldo_e_buck_typ_voltages,
+ .voltages_len = ARRAY_SIZE(ldo_e_buck_typ_voltages),
+ },
+ {
+ .regreg = AB3100_LDO_F,
+ .typ_voltages = ldo_f_typ_voltages,
+ .voltages_len = ARRAY_SIZE(ldo_f_typ_voltages),
+ },
+ {
+ .regreg = AB3100_LDO_G,
+ .typ_voltages = ldo_g_typ_voltages,
+ .voltages_len = ARRAY_SIZE(ldo_g_typ_voltages),
+ },
+ {
+ .regreg = AB3100_LDO_H,
+ .typ_voltages = ldo_h_typ_voltages,
+ .voltages_len = ARRAY_SIZE(ldo_h_typ_voltages),
+ },
+ {
+ .regreg = AB3100_LDO_K,
+ .typ_voltages = ldo_k_typ_voltages,
+ .voltages_len = ARRAY_SIZE(ldo_k_typ_voltages),
+ },
+ {
+ .regreg = AB3100_LDO_EXT,
+ /* No voltages for the external regulator */
+ },
+ {
+ .regreg = AB3100_BUCK,
+ .typ_voltages = ldo_e_buck_typ_voltages,
+ .voltages_len = ARRAY_SIZE(ldo_e_buck_typ_voltages),
+ },
+};
+
+/*
+ * General functions for enable, disable and is_enabled used for
+ * LDO: A,C,E,F,G,H,K,EXT and BUCK
+ */
+static int ab3100_enable_regulator(struct regulator_dev *reg)
+{
+ struct ab3100_regulator *abreg = reg->reg_data;
+ int err;
+ u8 regval;
+
+ err = ab3100_get_register_interruptible(abreg->ab3100, abreg->regreg,
+ &regval);
+ if (err) {
+ dev_warn(&reg->dev, "failed to get regid %d value\n",
+ abreg->regreg);
+ return err;
+ }
+
+ /* The regulator is already on, no reason to go further */
+ if (regval & AB3100_REG_ON_MASK)
+ return 0;
+
+ regval |= AB3100_REG_ON_MASK;
+
+ err = ab3100_set_register_interruptible(abreg->ab3100, abreg->regreg,
+ regval);
+ if (err) {
+ dev_warn(&reg->dev, "failed to set regid %d value\n",
+ abreg->regreg);
+ return err;
+ }
+
+ /* Per-regulator power on delay from spec */
+ switch (abreg->regreg) {
+ case AB3100_LDO_A: /* Fallthrough */
+ case AB3100_LDO_C: /* Fallthrough */
+ case AB3100_LDO_D: /* Fallthrough */
+ case AB3100_LDO_E: /* Fallthrough */
+ case AB3100_LDO_H: /* Fallthrough */
+ case AB3100_LDO_K:
+ udelay(200);
+ break;
+ case AB3100_LDO_F:
+ udelay(600);
+ break;
+ case AB3100_LDO_G:
+ udelay(400);
+ break;
+ case AB3100_BUCK:
+ mdelay(1);
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static int ab3100_disable_regulator(struct regulator_dev *reg)
+{
+ struct ab3100_regulator *abreg = reg->reg_data;
+ int err;
+ u8 regval;
+
+ /*
+ * LDO D is a special regulator. When it is disabled, the entire
+ * system is shut down. So this is handled specially.
+ */
+ if (abreg->regreg == AB3100_LDO_D) {
+ int i;
+
+ dev_info(&reg->dev, "disabling LDO D - shut down system\n");
+ /*
+ * Set regulators to default values, ignore any errors,
+ * we're going DOWN
+ */
+ for (i = 0; i < ARRAY_SIZE(ab3100_reg_init_order); i++) {
+ (void) ab3100_set_register_interruptible(abreg->ab3100,
+ ab3100_reg_init_order[i],
+ abreg->plfdata->reg_initvals[i]);
+ }
+
+ /* Setting LDO D to 0x00 cuts the power to the SoC */
+ return ab3100_set_register_interruptible(abreg->ab3100,
+ AB3100_LDO_D, 0x00U);
+
+ }
+
+ /*
+ * All other regulators are handled here
+ */
+ err = ab3100_get_register_interruptible(abreg->ab3100, abreg->regreg,
+ &regval);
+ if (err) {
+ dev_err(&reg->dev, "unable to get register 0x%x\n",
+ abreg->regreg);
+ return err;
+ }
+ regval &= ~AB3100_REG_ON_MASK;
+ return ab3100_set_register_interruptible(abreg->ab3100, abreg->regreg,
+ regval);
+}
+
+static int ab3100_is_enabled_regulator(struct regulator_dev *reg)
+{
+ struct ab3100_regulator *abreg = reg->reg_data;
+ u8 regval;
+ int err;
+
+ err = ab3100_get_register_interruptible(abreg->ab3100, abreg->regreg,
+ &regval);
+ if (err) {
+ dev_err(&reg->dev, "unable to get register 0x%x\n",
+ abreg->regreg);
+ return err;
+ }
+
+ return regval & AB3100_REG_ON_MASK;
+}
+
+static int ab3100_list_voltage_regulator(struct regulator_dev *reg,
+ unsigned selector)
+{
+ struct ab3100_regulator *abreg = reg->reg_data;
+
+ if (selector > abreg->voltages_len)
+ return -EINVAL;
+ return abreg->typ_voltages[selector];
+}
+
+static int ab3100_get_voltage_regulator(struct regulator_dev *reg)
+{
+ struct ab3100_regulator *abreg = reg->reg_data;
+ u8 regval;
+ int err;
+
+ /* Return the voltage for fixed regulators immediately */
+ if (abreg->fixed_voltage)
+ return abreg->fixed_voltage;
+
+ /*
+ * For variable types, read out setting and index into
+ * supplied voltage list.
+ */
+ err = ab3100_get_register_interruptible(abreg->ab3100,
+ abreg->regreg, &regval);
+ if (err) {
+ dev_warn(&reg->dev,
+ "failed to get regulator value in register %02x\n",
+ abreg->regreg);
+ return err;
+ }
+
+ /* The 3 highest bits index voltages */
+ regval &= 0xE0;
+ regval >>= 5;
+
+ if (regval > abreg->voltages_len) {
+ dev_err(&reg->dev,
+ "regulator register %02x contains an illegal voltage setting\n",
+ abreg->regreg);
+ return -EINVAL;
+ }
+
+ return abreg->typ_voltages[regval];
+}
+
+static int ab3100_get_best_voltage_index(struct regulator_dev *reg,
+ int min_uV, int max_uV)
+{
+ struct ab3100_regulator *abreg = reg->reg_data;
+ int i;
+ int bestmatch;
+ int bestindex;
+
+ /*
+ * Locate the minimum voltage fitting the criteria on
+ * this regulator. The switchable voltages are not
+ * in strict falling order so we need to check them
+ * all for the best match.
+ */
+ bestmatch = INT_MAX;
+ bestindex = -1;
+ for (i = 0; i < abreg->voltages_len; i++) {
+ if (abreg->typ_voltages[i] <= max_uV &&
+ abreg->typ_voltages[i] >= min_uV &&
+ abreg->typ_voltages[i] < bestmatch) {
+ bestmatch = abreg->typ_voltages[i];
+ bestindex = i;
+ }
+ }
+
+ if (bestindex < 0) {
+ dev_warn(&reg->dev, "requested %d<=x<=%d uV, out of range!\n",
+ min_uV, max_uV);
+ return -EINVAL;
+ }
+ return bestindex;
+}
+
+static int ab3100_set_voltage_regulator(struct regulator_dev *reg,
+ int min_uV, int max_uV)
+{
+ struct ab3100_regulator *abreg = reg->reg_data;
+ u8 regval;
+ int err;
+ int bestindex;
+
+ bestindex = ab3100_get_best_voltage_index(reg, min_uV, max_uV);
+ if (bestindex < 0)
+ return bestindex;
+
+ err = ab3100_get_register_interruptible(abreg->ab3100,
+ abreg->regreg, &regval);
+ if (err) {
+ dev_warn(&reg->dev,
+ "failed to get regulator register %02x\n",
+ abreg->regreg);
+ return err;
+ }
+
+ /* The highest three bits control the variable regulators */
+ regval &= ~0xE0;
+ regval |= (bestindex << 5);
+
+ err = ab3100_set_register_interruptible(abreg->ab3100,
+ abreg->regreg, regval);
+ if (err)
+ dev_warn(&reg->dev, "failed to set regulator register %02x\n",
+ abreg->regreg);
+
+ return err;
+}
+
+static int ab3100_set_suspend_voltage_regulator(struct regulator_dev *reg,
+ int uV)
+{
+ struct ab3100_regulator *abreg = reg->reg_data;
+ u8 regval;
+ int err;
+ int bestindex;
+ u8 targetreg;
+
+ if (abreg->regreg == AB3100_LDO_E)
+ targetreg = AB3100_LDO_E_SLEEP;
+ else if (abreg->regreg == AB3100_BUCK)
+ targetreg = AB3100_BUCK_SLEEP;
+ else
+ return -EINVAL;
+
+ /* LDO E and BUCK have special suspend voltages you can set */
+ bestindex = ab3100_get_best_voltage_index(reg, uV, uV);
+
+ err = ab3100_get_register_interruptible(abreg->ab3100,
+ targetreg, &regval);
+ if (err) {
+ dev_warn(&reg->dev,
+ "failed to get regulator register %02x\n",
+ targetreg);
+ return err;
+ }
+
+ /* The highest three bits control the variable regulators */
+ regval &= ~0xE0;
+ regval |= (bestindex << 5);
+
+ err = ab3100_set_register_interruptible(abreg->ab3100,
+ targetreg, regval);
+ if (err)
+ dev_warn(&reg->dev, "failed to set regulator register %02x\n",
+ abreg->regreg);
+
+ return err;
+}
+
+/*
+ * The external regulator can just define a fixed voltage.
+ */
+static int ab3100_get_voltage_regulator_external(struct regulator_dev *reg)
+{
+ struct ab3100_regulator *abreg = reg->reg_data;
+
+ return abreg->plfdata->external_voltage;
+}
+
+static struct regulator_ops regulator_ops_fixed = {
+ .enable = ab3100_enable_regulator,
+ .disable = ab3100_disable_regulator,
+ .is_enabled = ab3100_is_enabled_regulator,
+ .get_voltage = ab3100_get_voltage_regulator,
+};
+
+static struct regulator_ops regulator_ops_variable = {
+ .enable = ab3100_enable_regulator,
+ .disable = ab3100_disable_regulator,
+ .is_enabled = ab3100_is_enabled_regulator,
+ .get_voltage = ab3100_get_voltage_regulator,
+ .set_voltage = ab3100_set_voltage_regulator,
+ .list_voltage = ab3100_list_voltage_regulator,
+};
+
+static struct regulator_ops regulator_ops_variable_sleepable = {
+ .enable = ab3100_enable_regulator,
+ .disable = ab3100_disable_regulator,
+ .is_enabled = ab3100_is_enabled_regulator,
+ .get_voltage = ab3100_get_voltage_regulator,
+ .set_voltage = ab3100_set_voltage_regulator,
+ .set_suspend_voltage = ab3100_set_suspend_voltage_regulator,
+ .list_voltage = ab3100_list_voltage_regulator,
+};
+
+/*
+ * LDO EXT is an external regulator so it is really
+ * not possible to set any voltage locally here, AB3100
+ * is an on/off switch plain an simple. The external
+ * voltage is defined in the board set-up if any.
+ */
+static struct regulator_ops regulator_ops_external = {
+ .enable = ab3100_enable_regulator,
+ .disable = ab3100_disable_regulator,
+ .is_enabled = ab3100_is_enabled_regulator,
+ .get_voltage = ab3100_get_voltage_regulator_external,
+};
+
+static struct regulator_desc
+ab3100_regulator_desc[AB3100_NUM_REGULATORS] = {
+ {
+ .name = "LDO_A",
+ .id = AB3100_LDO_A,
+ .ops = &regulator_ops_fixed,
+ .type = REGULATOR_VOLTAGE,
+ },
+ {
+ .name = "LDO_C",
+ .id = AB3100_LDO_C,
+ .ops = &regulator_ops_fixed,
+ .type = REGULATOR_VOLTAGE,
+ },
+ {
+ .name = "LDO_D",
+ .id = AB3100_LDO_D,
+ .ops = &regulator_ops_fixed,
+ .type = REGULATOR_VOLTAGE,
+ },
+ {
+ .name = "LDO_E",
+ .id = AB3100_LDO_E,
+ .ops = &regulator_ops_variable_sleepable,
+ .type = REGULATOR_VOLTAGE,
+ },
+ {
+ .name = "LDO_F",
+ .id = AB3100_LDO_F,
+ .ops = &regulator_ops_variable,
+ .type = REGULATOR_VOLTAGE,
+ },
+ {
+ .name = "LDO_G",
+ .id = AB3100_LDO_G,
+ .ops = &regulator_ops_variable,
+ .type = REGULATOR_VOLTAGE,
+ },
+ {
+ .name = "LDO_H",
+ .id = AB3100_LDO_H,
+ .ops = &regulator_ops_variable,
+ .type = REGULATOR_VOLTAGE,
+ },
+ {
+ .name = "LDO_K",
+ .id = AB3100_LDO_K,
+ .ops = &regulator_ops_variable,
+ .type = REGULATOR_VOLTAGE,
+ },
+ {
+ .name = "LDO_EXT",
+ .id = AB3100_LDO_EXT,
+ .ops = &regulator_ops_external,
+ .type = REGULATOR_VOLTAGE,
+ },
+ {
+ .name = "BUCK",
+ .id = AB3100_BUCK,
+ .ops = &regulator_ops_variable_sleepable,
+ .type = REGULATOR_VOLTAGE,
+ },
+};
+
+/*
+ * NOTE: the following functions are regulators pluralis - it is the
+ * binding to the AB3100 core driver and the parent platform device
+ * for all the different regulators.
+ */
+
+static int __init ab3100_regulators_probe(struct platform_device *pdev)
+{
+ struct ab3100_platform_data *plfdata = pdev->dev.platform_data;
+ struct ab3100 *ab3100 = platform_get_drvdata(pdev);
+ int err = 0;
+ u8 data;
+ int i;
+
+ /* Check chip state */
+ err = ab3100_get_register_interruptible(ab3100,
+ AB3100_LDO_D, &data);
+ if (err) {
+ dev_err(&pdev->dev, "could not read initial status of LDO_D\n");
+ return err;
+ }
+ if (data & 0x10)
+ dev_notice(&pdev->dev,
+ "chip is already in active mode (Warm start)\n");
+ else
+ dev_notice(&pdev->dev,
+ "chip is in inactive mode (Cold start)\n");
+
+ /* Set up regulators */
+ for (i = 0; i < ARRAY_SIZE(ab3100_reg_init_order); i++) {
+ err = ab3100_set_register_interruptible(ab3100,
+ ab3100_reg_init_order[i],
+ plfdata->reg_initvals[i]);
+ if (err) {
+ dev_err(&pdev->dev, "regulator initialization failed with error %d\n",
+ err);
+ return err;
+ }
+ }
+
+ if (err) {
+ dev_err(&pdev->dev,
+ "LDO D regulator initialization failed with error %d\n",
+ err);
+ return err;
+ }
+
+ /* Register the regulators */
+ for (i = 0; i < AB3100_NUM_REGULATORS; i++) {
+ struct ab3100_regulator *reg = &ab3100_regulators[i];
+ struct regulator_dev *rdev;
+
+ /*
+ * Initialize per-regulator struct.
+ * Inherit platform data, this comes down from the
+ * i2c boarddata, from the machine. So if you want to
+ * see what it looks like for a certain machine, go
+ * into the machine I2C setup.
+ */
+ reg->ab3100 = ab3100;
+ reg->plfdata = plfdata;
+
+ /*
+ * Register the regulator, pass around
+ * the ab3100_regulator struct
+ */
+ rdev = regulator_register(&ab3100_regulator_desc[i],
+ &pdev->dev,
+ &plfdata->reg_constraints[i],
+ reg);
+
+ if (IS_ERR(rdev)) {
+ err = PTR_ERR(rdev);
+ dev_err(&pdev->dev,
+ "%s: failed to register regulator %s err %d\n",
+ __func__, ab3100_regulator_desc[i].name,
+ err);
+ i--;
+ /* remove the already registered regulators */
+ while (i > 0) {
+ regulator_unregister(ab3100_regulators[i].rdev);
+ i--;
+ }
+ return err;
+ }
+
+ /* Then set a pointer back to the registered regulator */
+ reg->rdev = rdev;
+ }
+
+ return 0;
+}
+
+static int __exit ab3100_regulators_remove(struct platform_device *pdev)
+{
+ int i;
+
+ for (i = 0; i < AB3100_NUM_REGULATORS; i++) {
+ struct ab3100_regulator *reg = &ab3100_regulators[i];
+
+ regulator_unregister(reg->rdev);
+ }
+ return 0;
+}
+
+static struct platform_driver ab3100_regulators_driver = {
+ .driver = {
+ .name = "ab3100-regulators",
+ .owner = THIS_MODULE,
+ },
+ .probe = ab3100_regulators_probe,
+ .remove = __exit_p(ab3100_regulators_remove),
+};
+
+static __init int ab3100_regulators_init(void)
+{
+ return platform_driver_register(&ab3100_regulators_driver);
+}
+
+static __exit void ab3100_regulators_exit(void)
+{
+ platform_driver_register(&ab3100_regulators_driver);
+}
+
+subsys_initcall(ab3100_regulators_init);
+module_exit(ab3100_regulators_exit);
+
+MODULE_AUTHOR("Mattias Wallin <mattias.wallin@stericsson.com>");
+MODULE_DESCRIPTION("AB3100 Regulator driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:ab3100-regulators");