Messages in this thread | | | Date | Mon, 19 Oct 2009 23:35:43 +0200 | From | Pavel Machek <> | Subject | Re: [PATCH] power: pcf50633: introduces battery charging current control |
| |
On Wed 2009-10-14 01:59:04, Paul Fertser wrote: > From: Balaji Rao <balajirrao@openmoko.org> > > Signed-off-by: Balaji Rao <balajirrao@openmoko.org> > Signed-off-by: Paul Fertser <fercerpav@gmail.com> > --- > drivers/power/pcf50633-charger.c | 73 ++++++++++++++++++++++++++++++++++--- > include/linux/mfd/pcf50633/core.h | 2 + > 2 files changed, 70 insertions(+), 5 deletions(-) > > diff --git a/drivers/power/pcf50633-charger.c b/drivers/power/pcf50633-charger.c > index 48e92c0..13f2839 100644 > --- a/drivers/power/pcf50633-charger.c > +++ b/drivers/power/pcf50633-charger.c > @@ -48,16 +48,21 @@ int pcf50633_mbc_usb_curlim_set(struct pcf50633 *pcf, int ma) > u8 bits; > int charging_start = 1; > u8 mbcs2, chgmod; > + unsigned int mbcc5; > > - if (ma >= 1000) > + if (ma >= 1000) { > bits = PCF50633_MBCC7_USB_1000mA; > - else if (ma >= 500) > + ma = 1000; > + } else if (ma >= 500) { > bits = PCF50633_MBCC7_USB_500mA; > - else if (ma >= 100) > + ma = 500; > + } else if (ma >= 100) { > bits = PCF50633_MBCC7_USB_100mA; > - else { > + ma = 100; > + } else { > bits = PCF50633_MBCC7_USB_SUSPEND; > charging_start = 0; > + ma = 0; > } > > ret = pcf50633_reg_set_bit_mask(pcf, PCF50633_REG_MBCC7, > @@ -67,7 +72,24 @@ int pcf50633_mbc_usb_curlim_set(struct pcf50633 *pcf, int ma) > else > dev_info(pcf->dev, "usb curlim to %d mA\n", ma); > > - /* Manual charging start */ > + /* > + * We limit the charging current to be the USB current limit. > + * The reason is that on pcf50633, when it enters PMU Standby mode, > + * which it does when the device goes "off", the USB current limit > + * reverts to the variant default. In at least one common case, that > + * default is 500mA. By setting the charging current to be the same > + * as the USB limit we set here before PMU standby, we enforce it only > + * using the correct amount of current even when the USB current limit > + * gets reset to the wrong thing > + */ > + > + if (mbc->pcf->pdata->chg_ref_current_ma) { > + mbcc5 = (ma << 8) / mbc->pcf->pdata->chg_ref_current_ma; > + if (mbcc5 > 255) > + mbcc5 = 255; > + pcf50633_reg_write(mbc->pcf, PCF50633_REG_MBCC5, mbcc5); > + } > + > mbcs2 = pcf50633_reg_read(pcf, PCF50633_REG_MBCS2); > chgmod = (mbcs2 & PCF50633_MBCS2_MBC_MASK); > > @@ -157,9 +179,50 @@ static ssize_t set_usblim(struct device *dev, > > static DEVICE_ATTR(usb_curlim, S_IRUGO | S_IWUSR, show_usblim, set_usblim); > > +static ssize_t > +show_chglim(struct device *dev, struct device_attribute *attr, char *buf) > +{ > + struct pcf50633_mbc *mbc = dev_get_drvdata(dev); > + u8 mbcc5 = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCC5); > + unsigned int ma; > + > + if (!mbc->pcf->pdata->chg_ref_current_ma) > + return -ENODEV; > + > + ma = (mbc->pcf->pdata->chg_ref_current_ma * mbcc5) >> 8; > + > + return sprintf(buf, "%u\n", ma); > +} > + > +static ssize_t set_chglim(struct device *dev, > + struct device_attribute *attr, const char *buf, size_t count) > +{ > + struct pcf50633_mbc *mbc = dev_get_drvdata(dev); > + unsigned long ma; > + unsigned int mbcc5; > + int ret; > + > + if (!mbc->pcf->pdata->chg_ref_current_ma) > + return -ENODEV; > + > + ret = strict_strtoul(buf, 10, &ma); > + if (ret) > + return -EINVAL; > + > + mbcc5 = (ma << 8) / mbc->pcf->pdata->chg_ref_current_ma; > + if (mbcc5 > 255) > + mbcc5 = 255; > + pcf50633_reg_write(mbc->pcf, PCF50633_REG_MBCC5, mbcc5); > + > + return count; > +} > + > +static DEVICE_ATTR(chg_curlim, S_IRUGO | S_IWUSR, show_chglim, set_chglim); > + > static struct attribute *pcf50633_mbc_sysfs_entries[] = { > &dev_attr_chgmode.attr, > &dev_attr_usb_curlim.attr, > + &dev_attr_chg_curlim.attr, > NULL, > }; > > diff --git a/include/linux/mfd/pcf50633/core.h b/include/linux/mfd/pcf50633/core.h > index 9aba7b7..222dd90 100644 > --- a/include/linux/mfd/pcf50633/core.h > +++ b/include/linux/mfd/pcf50633/core.h > @@ -31,6 +31,8 @@ struct pcf50633_platform_data { > > int charging_restart_interval; > > + int chg_ref_current_ma; > + > /* Callbacks */ > void (*probe_done)(struct pcf50633 *); > void (*mbc_event_callback)(struct pcf50633 *, int);
-- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
| |