Re: [PATCH] regulator: lp873x: Update the enable mask for LDOs and BUCKs

From: Tero Kristo
Date: Mon Oct 09 2017 - 11:36:06 EST

ï
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

On 09/10/17 17:20, Mark Brown wrote:
On Wed, Sep 27, 2017 at 05:55:40PM +0530, Keerthy wrote:
The reset value of the EN_PIN_CTRL bit fields of LDOs and BUCKs
need not be set correctly. Hence update the enable mask to include
the EN_PIN_CTRL bit. While enabling this should be set to 1 so
that all the regulators are tied to EN pin.

I'm not sure I follow the logic here entirely. It sounds like this is a
register bit to control if the regulators are enabled and disabled via a
GPIO instead of the register which is something that people might want
to use in some systems. Shouldn't this be dependent on some system
configration instead?

The EN signal coming in to the PMIC is actually used to poweroff the system completely. There is no other mechanism for doing this in lp873x based systems, they removed the bit for controlling dev-power-off from the register space. If the EN bit is down for a specific regulator, it won't go down when attempting to poweroff the system, otherwise the state of a regulator is the result of (EN_PIN | EN_BIT).

I wonder if we should tie this somehow to the system-power-controller property though.... If the PMIC is not system-power-controller, we should disable the EN_PIN_CTRL from all regulators so that they don't go down if the EN_PIN itself is floating for example.

-Tero



Signed-off-by: Keerthy <j-keerthy@xxxxxx>
---
drivers/regulator/lp873x-regulator.c | 19 ++++++++++---------
include/linux/mfd/lp873x.h | 4 ++++
2 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/drivers/regulator/lp873x-regulator.c b/drivers/regulator/lp873x-regulator.c
index 70e3df6..77bea82 100644
--- a/drivers/regulator/lp873x-regulator.c
+++ b/drivers/regulator/lp873x-regulator.c
@@ -20,7 +20,7 @@
#include <linux/mfd/lp873x.h>
#define LP873X_REGULATOR(_name, _id, _of, _ops, _n, _vr, _vm, _er, _em, \
- _delay, _lr, _cr) \
+ _dv, _delay, _lr, _cr) \
[_id] = { \
.desc = { \
.name = _name, \
@@ -36,6 +36,7 @@
.vsel_mask = _vm, \
.enable_reg = _er, \
.enable_mask = _em, \
+ .disable_val = _dv, \
.ramp_delay = _delay, \
.linear_ranges = _lr, \
.n_linear_ranges = ARRAY_SIZE(_lr), \
@@ -175,21 +176,21 @@ static int lp873x_buck_get_current_limit(struct regulator_dev *rdev)
LP873X_REGULATOR("BUCK0", LP873X_BUCK_0, "buck0", lp873x_buck01_ops,
256, LP873X_REG_BUCK0_VOUT,
LP873X_BUCK0_VOUT_BUCK0_VSET, LP873X_REG_BUCK0_CTRL_1,
- LP873X_BUCK0_CTRL_1_BUCK0_EN, 10000,
- buck0_buck1_ranges, LP873X_REG_BUCK0_CTRL_2),
+ LP873X_BUCK_ENABLE_MASK, LP873X_BUCK_DISABLE_VAL,
+ 10000, buck0_buck1_ranges, LP873X_REG_BUCK0_CTRL_2),
LP873X_REGULATOR("BUCK1", LP873X_BUCK_1, "buck1", lp873x_buck01_ops,
256, LP873X_REG_BUCK1_VOUT,
LP873X_BUCK1_VOUT_BUCK1_VSET, LP873X_REG_BUCK1_CTRL_1,
- LP873X_BUCK1_CTRL_1_BUCK1_EN, 10000,
- buck0_buck1_ranges, LP873X_REG_BUCK1_CTRL_2),
+ LP873X_BUCK_ENABLE_MASK, LP873X_BUCK_DISABLE_VAL,
+ 10000, buck0_buck1_ranges, LP873X_REG_BUCK1_CTRL_2),
LP873X_REGULATOR("LDO0", LP873X_LDO_0, "ldo0", lp873x_ldo01_ops, 26,
LP873X_REG_LDO0_VOUT, LP873X_LDO0_VOUT_LDO0_VSET,
- LP873X_REG_LDO0_CTRL,
- LP873X_LDO0_CTRL_LDO0_EN, 0, ldo0_ldo1_ranges, 0xFF),
+ LP873X_REG_LDO0_CTRL, LP873X_LDO_ENABLE_MASK,
+ LP873X_LDO_DISABLE_VAL, 0, ldo0_ldo1_ranges, 0xFF),
LP873X_REGULATOR("LDO1", LP873X_LDO_1, "ldo1", lp873x_ldo01_ops, 26,
LP873X_REG_LDO1_VOUT, LP873X_LDO1_VOUT_LDO1_VSET,
- LP873X_REG_LDO1_CTRL,
- LP873X_LDO1_CTRL_LDO1_EN, 0, ldo0_ldo1_ranges, 0xFF),
+ LP873X_REG_LDO1_CTRL, LP873X_LDO_ENABLE_MASK,
+ LP873X_LDO_DISABLE_VAL, 0, ldo0_ldo1_ranges, 0xFF),
};
static int lp873x_regulator_probe(struct platform_device *pdev)
diff --git a/include/linux/mfd/lp873x.h b/include/linux/mfd/lp873x.h
index edbec83..53888d4 100644
--- a/include/linux/mfd/lp873x.h
+++ b/include/linux/mfd/lp873x.h
@@ -77,6 +77,8 @@
#define LP873X_BUCK0_CTRL_1_BUCK0_RDIS_EN BIT(2)
#define LP873X_BUCK0_CTRL_1_BUCK0_EN_PIN_CTRL BIT(1)
#define LP873X_BUCK0_CTRL_1_BUCK0_EN BIT(0)
+#define LP873X_BUCK_ENABLE_MASK (BIT(0) | BIT(1))
+#define LP873X_BUCK_DISABLE_VAL BIT(1)
#define LP873X_BUCK0_CTRL_2_BUCK0_ILIM 0x38
#define LP873X_BUCK0_CTRL_2_BUCK0_SLEW_RATE 0x07
@@ -96,6 +98,8 @@
#define LP873X_LDO0_CTRL_LDO0_RDIS_EN BIT(2)
#define LP873X_LDO0_CTRL_LDO0_EN_PIN_CTRL BIT(1)
#define LP873X_LDO0_CTRL_LDO0_EN BIT(0)
+#define LP873X_LDO_ENABLE_MASK (BIT(0) | BIT(1))
+#define LP873X_LDO_DISABLE_VAL BIT(1)
#define LP873X_LDO1_CTRL_LDO1_RDIS_EN BIT(2)
#define LP873X_LDO1_CTRL_LDO1_EN_PIN_CTRL BIT(1)
--
1.9.1