Re: [PATCH 3/7] ath9k: Add support for reading the EEPROM data using the nvmem API

From: Alban
Date: Thu Mar 23 2017 - 10:44:34 EST


On Tue, 14 Mar 2017 00:53:55 +0100
Christian Lamparter <chunkeey@xxxxxxxxxxxxxx> wrote:

> On Monday, March 13, 2017 10:05:11 PM CET Alban wrote:
> > Currently SoC platforms use a firmware request to get the EEPROM data.
> > This is mostly a hack and rely on using a user-helper scripts which is
> > deprecated. A nicer alternative is to use the nvmem API which was
> > designed for this kind of task.
> >
> > Furthermore we let CONFIG_ATH9K_AHB select CONFIG_NVMEM as such
> > devices will generally use this method for loading the EEPROM data.
> >
> > Signed-off-by: Alban <albeu@xxxxxxx>
> > ---
> > @@ -654,6 +656,25 @@ static int ath9k_init_softc(u16 devid, struct ath_softc *sc,
> > if (ret)
> > return ret;
> >
> > + /* If the EEPROM hasn't been retrieved via firmware request
> > + * use the nvmem API insted.
> > + */
> > + if (!ah->eeprom_blob) {
> > + struct nvmem_cell *eeprom_cell;
> > +
> > + eeprom_cell = nvmem_cell_get(ah->dev, "eeprom");
> > + if (!IS_ERR(eeprom_cell)) {
> > + ah->eeprom_data = nvmem_cell_read(
> > + eeprom_cell, &ah->eeprom_size);
> > + nvmem_cell_put(eeprom_cell);
> > +
> > + if (IS_ERR(ah->eeprom_data)) {
> > + dev_err(ah->dev, "failed to read eeprom");
> > + return PTR_ERR(ah->eeprom_data);
> > + }
> > + }
> > + }
> > +
> > if (ath9k_led_active_high != -1)
> > ah->config.led_active_high = ath9k_led_active_high == 1;
> >
> Are you sure this works with AR93XX SoCs that have the calibration data
> in the OTP?

I only tested this on an ar9132 platform, so it might well be that a
few things are missing for the newer SoC. However this shouldn't break
anything existing as a platform needs to define an nvmem cell on the
athk9 device for this code to be used at all.

Alban

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