[PATCH] Add support for bq27521 battery monitor

Pavel Machek pavel at ucw.cz
Thu Nov 9 13:45:40 PST 2017


On Thu 2017-11-09 22:29:45, Pali Rohár wrote:
> On Thursday 09 November 2017 22:06:15 Pavel Machek wrote:
> > diff --git a/drivers/power/supply/bq27xxx_battery.c b/drivers/power/supply/bq27xxx_battery.c
> > index ed44439..ee2851a 100644
> > --- a/drivers/power/supply/bq27xxx_battery.c
> > +++ b/drivers/power/supply/bq27xxx_battery.c
> > @@ -381,6 +381,30 @@ static u8 bq27xxx_regs[][BQ27XXX_REG_MAX] = {
> >  		[BQ27XXX_REG_AP] = INVALID_REG_ADDR,
> >  		BQ27XXX_DM_REG_ROWS,
> >  	},
> > +	[BQ27521] = {				/* FIXME */
> > +		[BQ27XXX_REG_CTRL] = 0x02,
> > +		[BQ27XXX_REG_TEMP] = 0x0a,
> > +		[BQ27XXX_REG_INT_TEMP] = INVALID_REG_ADDR,
> > +		[BQ27XXX_REG_VOLT] = 0x0c,
> > +		[BQ27XXX_REG_AI] = 0x0e,
> > +		[BQ27XXX_REG_FLAGS] = 0x08,
> > +		[BQ27XXX_REG_TTE] = INVALID_REG_ADDR,
> > +		[BQ27XXX_REG_TTF] = INVALID_REG_ADDR,
> > +		[BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
> > +		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
> > +		[BQ27XXX_REG_NAC] = INVALID_REG_ADDR,
> > +		[BQ27XXX_REG_FCC] = INVALID_REG_ADDR,
> > +		[BQ27XXX_REG_CYCT] = INVALID_REG_ADDR,
> > +		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
> > +		[BQ27XXX_REG_SOC] = INVALID_REG_ADDR,
> > +		[BQ27XXX_REG_DCAP] = INVALID_REG_ADDR,
> > +		[BQ27XXX_REG_AP] = INVALID_REG_ADDR,
> > +		[BQ27XXX_DM_CTRL] = INVALID_REG_ADDR,
> > +		[BQ27XXX_DM_CLASS] = INVALID_REG_ADDR,
> > +		[BQ27XXX_DM_BLOCK] = INVALID_REG_ADDR,
> > +		[BQ27XXX_DM_DATA] = INVALID_REG_ADDR,
> > +		[BQ27XXX_DM_CKSUM] = INVALID_REG_ADDR,
> > +	},
> >  	[BQ27530] = {
> >  		[BQ27XXX_REG_CTRL] = 0x00,
> >  		[BQ27XXX_REG_TEMP] = 0x06,
> 
> Hi! IIRC those registers are valid only for sn27521 chip in revision 14
> (or new). For older revision is used different register map. And
> detection of chip revision is somehow possible via some registers.

Yes, I know.. I even had this, but as I can't test it, and early N950
samples should be very very rare, I'd prefer the patch as is.

@@ -1905,6 +1940,23 @@ int bq27xxx_battery_setup(struct bq27xxx_device_info *di)
 
 	dev_info(di->dev, "support ver. %s enabled\n", DRIVER_VERSION);
 
+	if (di->chip == BQ27521) {
+		int val;
+		val = di->bus.read(di, 0x32, false);
+		if (val == 0x2100) {
+			printk("rev. 13 chip detected; add support\n");
+			/* https://elinux.org/N950 has details */
+			return PTR_ERR(ENODEV);
+		}
+
+		val = di->bus.read(di, 0x34, false);
+		if ((val & 0xff00) != 0x2100) {
+			printk("rev. 14 chip not detected?!\n");
+			return PTR_ERR(EINVAL);
+		}
+		printk("verified chip rev. 14\n");
+	}
+
 	bq27xxx_battery_settings(di);
 	bq27xxx_battery_update(di);
 

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 181 bytes
Desc: Digital signature
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20171109/c8612126/attachment.sig>


More information about the linux-arm-kernel mailing list