On Tue, Dec 06, 2011 at 04:49:37AM +0200, Felipe Contreras wrote: > Not really. There are 6 bits: 640, 320, 160, 80, 40, 20. So values > from 0 to 1260mV can be represented, at steps of 20mV. A value of 0 > means 3.5V. I just checked it. You'r driver just writes 0x42 to the register, which makes use of the described platform specific resistor. > bq2415x_i2c_write(cli, BQ2415X_CHG_CTL, 0x42); I know that 42 is the "Answer to the Ultimate Question of Life, the Universe, and Everything" [0]. But in this case 0x42 is platform specific. Check page 30 in the specs, From Table 9 onwards. > > [...] > > > >> + bq2415x_i2c_write(cli, BQ2415X_CHG_CTL, 0x42); > >> + bq2415x_set_voltage(cli, 0, 4200000); > >> + bq2415x_set_current_limit(cli, 1800000, 1800000); > > > > So it always charges with 1.8A? Shouldn't this be dependent on the > > input source (e.g. 500mA from USB)? Also what's if no charger is > > connected at all? > > No. I'm hard-coding those values, but I wrote the functions > (set_voltate, set_current_limit) so all values are supported. > > What is missing is the code to connect this driver to the charger > detector driver (isp1704), so those values are determined dynamically. ok, I was talking about the current state ;) > > Apart from this I think those values should be exposed to sysfs > > via /sys/class/power_supply. > > Perhaps. Although I don't see much of the power supply interface that > could be useful here, but if so, I guess this should be indeed in > 'drivers/power'. So it may need some new entries. Normal mobile userspace wants to know at least charging status & speed. Also it's probably a good idea to make current_limit sysfs entry writeable, so that advanced users can overwrite a autodetected value (e.g. a dumb wallcharger may be detected as 100mA, but can provide 1A). [0] http://en.wikipedia.org/wiki/Phrases_from_The_Hitchhiker%27s_Guide_to_the_Galaxy -- Sebasitan
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