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 <rlipp...@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

Reply via email to