Re: [RFT][PATCH 2/2] regulator: lm363x: Fix n_voltages setting for lm36274

From: Dan Murphy
Date: Wed Jun 26 2019 - 11:07:11 EST


Hello

On 6/26/19 8:26 AM, Axel Lin wrote:
According to the datasheet http://www.ti.com/lit/ds/symlink/lm36274.pdf:
Table 23. VPOS Bias Register Field Descriptions VPOS[5:0]:
VPOS voltage (50-mV steps): VPOS = 4 V + (Code à 50 mV), 6.5 V max
000000 = 4 V
000001 = 4.05 V
:
011110 = 5.5 V (Default)
:
110010 = 6.5 V
110011 to 111111 map to 6.5 V

So the LM36274_LDO_VSEL_MAX should be 0b110010 (0x32).
The valid selectors are 0 ... LM36274_LDO_VSEL_MAX, n_voltages should be
LM36274_LDO_VSEL_MAX + 1. Similarly, the n_voltages should be
LM36274_BOOST_VSEL_MAX + 1 for LM36274_BOOST.

Fixes: bff5e8071533 ("regulator: lm363x: Add support for LM36274")
Signed-off-by: Axel Lin <axel.lin@xxxxxxxxxx>
---
drivers/regulator/lm363x-regulator.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/regulator/lm363x-regulator.c b/drivers/regulator/lm363x-regulator.c
index e4a27d63bf90..4b9f618b07e9 100644
--- a/drivers/regulator/lm363x-regulator.c
+++ b/drivers/regulator/lm363x-regulator.c
@@ -36,7 +36,7 @@
/* LM36274 */
#define LM36274_BOOST_VSEL_MAX 0x3f
-#define LM36274_LDO_VSEL_MAX 0x34
+#define LM36274_LDO_VSEL_MAX 0x32

This does not seem correct the max number of voltages are 0x34.

The register is zero based so you can have 33 voltage select levels and + 1 is 34 total selectors

Liam/Mark correct me if I am incorrect.

Dan


#define LM36274_VOLTAGE_MIN 4000000
/* Common */
@@ -226,7 +226,7 @@ static const struct regulator_desc lm363x_regulator_desc[] = {
.of_match = "vboost",
.id = LM36274_BOOST,
.ops = &lm363x_boost_voltage_table_ops,
- .n_voltages = LM36274_BOOST_VSEL_MAX,
+ .n_voltages = LM36274_BOOST_VSEL_MAX + 1,
.min_uV = LM36274_VOLTAGE_MIN,
.uV_step = LM363X_STEP_50mV,
.type = REGULATOR_VOLTAGE,
@@ -239,7 +239,7 @@ static const struct regulator_desc lm363x_regulator_desc[] = {
.of_match = "vpos",
.id = LM36274_LDO_POS,
.ops = &lm363x_regulator_voltage_table_ops,
- .n_voltages = LM36274_LDO_VSEL_MAX,
+ .n_voltages = LM36274_LDO_VSEL_MAX + 1,
.min_uV = LM36274_VOLTAGE_MIN,
.uV_step = LM363X_STEP_50mV,
.type = REGULATOR_VOLTAGE,
@@ -254,7 +254,7 @@ static const struct regulator_desc lm363x_regulator_desc[] = {
.of_match = "vneg",
.id = LM36274_LDO_NEG,
.ops = &lm363x_regulator_voltage_table_ops,
- .n_voltages = LM36274_LDO_VSEL_MAX,
+ .n_voltages = LM36274_LDO_VSEL_MAX + 1,
.min_uV = LM36274_VOLTAGE_MIN,
.uV_step = LM363X_STEP_50mV,
.type = REGULATOR_VOLTAGE,