On 11/18/21 04:02, Linus Walleij wrote:

On Tue, Nov 16, 2021 at 1:25 PM Matti Vaittinen
[off-list ref] wrote:

quoted

The power-supply core supports concept of OCV (Open Circuit Voltage) =>
SOC (State Of Charge) conversion tables. Usually these tables are used
to estimate SOC based on OCV. Some systems use so called "Zero Adjust"
where at the near end-of-battery condition the SOC from coulomb counter
is used to retrieve the OCV - and OCV and VSYS difference is used to
re-estimate the battery capacity.

Add helper to do look-up the other-way around and also get the OCV
based on SOC

Signed-off-by: Matti Vaittinen <redacted>

It seems you will need this for your chargers indeed.

quoted

+int power_supply_dcap2ocv_simple(struct power_supply_battery_ocv_table *table,
+                               int table_len, int dcap)
+{
+       int i, ocv, tmp;
+
+       for (i = 0; i < table_len; i++)
+               if (dcap > table[i].capacity * 10)
+                       break;
+
+       if (i > 0 && i < table_len) {
+               tmp = (table[i - 1].ocv - table[i].ocv) *
+                     (dcap - table[i].capacity * 10);
+
+               tmp /= (table[i - 1].capacity - table[i].capacity) * 10;
+               ocv = tmp + table[i].ocv;
+       } else if (i == 0) {
+               ocv = table[0].ocv;
+       } else {
+               ocv = table[table_len - 1].ocv;
+       }
+
+       return ocv;
+}
+EXPORT_SYMBOL_GPL(power_supply_dcap2ocv_simple);

Rewrite this using the library fixpoint interpolation function but just
copypasting from my patch:
https://lore.kernel.org/linux-pm/20211116230233.2167104-1-linus.walleij@linaro.org/ (local)

Thanks :)
I actually saw this (yesterday?) but didn't revise my patches. Thanks 
for the head's up - it's always good to have this kind of helpers :)

Other than that it looks good to me!

Thanks!

Best Regards
     --Matti


-- 
The Linux Kernel guy at ROHM Semiconductors

Matti Vaittinen, Linux device drivers
ROHM Semiconductors, Finland SWDC
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90220 OULU
FINLAND

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