lkml.org 
[lkml]   [2014]   [Feb]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v4 16/16] regulator: max14577: Implement SUSPEND mode for MAX77836 LDO-s
Date
The MAX77836 LDO regulators support low power mode. In this mode the
maximum load current is 5 mA and the quiescent supply current is 1.5 uA.

This patch adds support for mode REGULATOR_MODE_STANDBY (and NORMAL) to
LDO regulators by implementing the set_mode() and get_mode() operations.
However the necessary regulator constraints (valid modes) are not parsed
by of_regulator_match() so the driver adds them manually.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
---
drivers/regulator/max14577.c | 61 ++++++++++++++++++++++++++++++++--
include/linux/mfd/max14577-private.h | 2 ++
2 files changed, 61 insertions(+), 2 deletions(-)

diff --git a/drivers/regulator/max14577.c b/drivers/regulator/max14577.c
index 6547cb3146e3..79981af198bf 100644
--- a/drivers/regulator/max14577.c
+++ b/drivers/regulator/max14577.c
@@ -18,9 +18,10 @@
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
#include <linux/mfd/max14577.h>
#include <linux/mfd/max14577-private.h>
-#include <linux/regulator/of_regulator.h>

static int max14577_reg_is_enabled(struct regulator_dev *rdev)
{
@@ -85,6 +86,45 @@ static int max14577_reg_set_current_limit(struct regulator_dev *rdev,
reg_data);
}

+static unsigned int max77836_reg_ldo_get_mode(struct regulator_dev *rdev)
+{
+ u8 reg_data;
+ int err;
+
+ err = max14577_read_reg(rdev->regmap, rdev->desc->enable_reg,
+ &reg_data);
+ if (err) {
+ dev_err(rdev_get_dev(rdev),
+ "Error reading control register for %d: %d\n",
+ rdev_get_id(rdev), err);
+ return REGULATOR_MODE_NORMAL;
+ }
+
+ reg_data &= rdev->desc->enable_mask;
+
+ if (reg_data == MAX77836_CNFG1_LDO_PWRMD_LOW_POWER)
+ return REGULATOR_MODE_STANDBY;
+
+ return REGULATOR_MODE_NORMAL;
+}
+
+static int max77836_reg_ldo_set_mode(struct regulator_dev *rdev,
+ unsigned int mode)
+{
+ switch (mode) {
+ case REGULATOR_MODE_STANDBY:
+ return max14577_update_reg(rdev->regmap,
+ rdev->desc->enable_reg, rdev->desc->enable_mask,
+ MAX77836_CNFG1_LDO_PWRMD_LOW_POWER);
+
+ case REGULATOR_MODE_NORMAL:
+ return regulator_enable_regmap(rdev);
+
+ default:
+ return -EINVAL;
+ }
+}
+
static struct regulator_ops max14577_safeout_ops = {
.is_enabled = regulator_is_enabled_regmap,
.enable = regulator_enable_regmap,
@@ -131,7 +171,8 @@ static struct regulator_ops max77836_ldo_ops = {
.map_voltage = regulator_map_voltage_linear,
.get_voltage_sel = regulator_get_voltage_sel_regmap,
.set_voltage_sel = regulator_set_voltage_sel_regmap,
- /* TODO: add .set_suspend_mode */
+ .get_mode = max77836_reg_ldo_get_mode,
+ .set_mode = max77836_reg_ldo_set_mode,
};

static const struct regulator_desc max77836_supported_regulators[] = {
@@ -198,6 +239,19 @@ static struct of_regulator_match max77836_regulator_matches[] = {
{ .name = "LDO2", },
};

+static void
+max77836_regulator_init_constraints(struct of_regulator_match *matches)
+{
+ int i;
+ struct regulation_constraints *c;
+
+ for (i = MAX77836_LDO1; i <= MAX77836_LDO2; i++) {
+ c = &matches[i].init_data->constraints;
+ c->valid_modes_mask = REGULATOR_MODE_NORMAL
+ | REGULATOR_MODE_STANDBY;
+ }
+}
+
static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev,
enum maxim_device_type dev_type)
{
@@ -232,6 +286,9 @@ static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev,

of_node_put(np);

+ if (dev_type == MAXIM_DEVICE_TYPE_MAX77836)
+ max77836_regulator_init_constraints(regulator_matches);
+
return ret;
}

diff --git a/include/linux/mfd/max14577-private.h b/include/linux/mfd/max14577-private.h
index 33700662fbb4..5eb164d91625 100644
--- a/include/linux/mfd/max14577-private.h
+++ b/include/linux/mfd/max14577-private.h
@@ -333,6 +333,8 @@ enum max77836_pmic_reg {
#define MAX77836_CNFG1_LDO_TV_SHIFT 0
#define MAX77836_CNFG1_LDO_PWRMD_MASK (0x3 << MAX77836_CNFG1_LDO_PWRMD_SHIFT)
#define MAX77836_CNFG1_LDO_TV_MASK (0x3f << MAX77836_CNFG1_LDO_TV_SHIFT)
+/* Value to write to CONFIG1/PWRMD field for enabling low power mode */
+#define MAX77836_CNFG1_LDO_PWRMD_LOW_POWER BIT(MAX77836_CNFG1_LDO_PWRMD_SHIFT)

/* LDO1/LDO2 CONFIG2 register */
#define MAX77836_CNFG2_LDO_OVCLMPEN_SHIFT 7
--
1.7.9.5


\
 
 \ /
  Last update: 2014-02-24 13:01    [W:0.154 / U:17.512 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site