lkml.org 
[lkml]   [2017]   [Nov]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] hwmon: (pmbus/lm25066) Default coefficients for low current limit
Date
There seems to be no way to detect the value of the CL/GAIN pin
from the device using PMBus.

Low current mode seems to be recommended (from LM5066 datasheet) for
improved current reporting accuracy in a typical design.

Assume the device is in low current mode unless the register override
bit is set and indicates high current limit mode.

Signed-off-by: Robert Lippert <rlippert@google.com>
---
drivers/hwmon/pmbus/lm25066.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/hwmon/pmbus/lm25066.c b/drivers/hwmon/pmbus/lm25066.c
index aa052f4449a9..f6ae7b4cf705 100644
--- a/drivers/hwmon/pmbus/lm25066.c
+++ b/drivers/hwmon/pmbus/lm25066.c
@@ -43,6 +43,7 @@ enum chips { lm25056, lm25063, lm25066, lm5064, lm5066, lm5066i };
#define LM25066_READ_AVG_IIN 0xde
#define LM25066_READ_AVG_PIN 0xdf

+#define LM25066_DEV_SETUP_CL_CONFIG BIT(2) /* Use pin or SMBus values */
#define LM25066_DEV_SETUP_CL BIT(4) /* Current limit */

/* LM25056 only */
@@ -526,16 +527,22 @@ static int lm25066_probe(struct i2c_client *client,
info->R[PSC_VOLTAGE_OUT] = coeff[PSC_VOLTAGE_OUT].R;
info->R[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN].R;
info->R[PSC_POWER] = coeff[PSC_POWER].R;
- if (config & LM25066_DEV_SETUP_CL) {
- info->m[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN_L].m;
- info->b[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN_L].b;
- info->m[PSC_POWER] = coeff[PSC_POWER_L].m;
- info->b[PSC_POWER] = coeff[PSC_POWER_L].b;
- } else {
+
+ /*
+ * Assume chip is in low current limit/gain mode by default unless
+ * the register override is asserted AND indicates high limit mode.
+ */
+ if ((config & LM25066_DEV_SETUP_CL_CONFIG) &&
+ (config & LM25066_DEV_SETUP_CL)) {
info->m[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN].m;
info->b[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN].b;
info->m[PSC_POWER] = coeff[PSC_POWER].m;
info->b[PSC_POWER] = coeff[PSC_POWER].b;
+ } else {
+ info->m[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN_L].m;
+ info->b[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN_L].b;
+ info->m[PSC_POWER] = coeff[PSC_POWER_L].m;
+ info->b[PSC_POWER] = coeff[PSC_POWER_L].b;
}

return pmbus_do_probe(client, id, info);
--
2.15.0.417.g466bffb3ac-goog
\
 
 \ /
  Last update: 2017-11-28 01:30    [W:0.059 / U:1.644 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site