Hi Andrew, Andrew Lunn <andrew@xxxxxxx> writes: >> +struct g762_data { >> + struct i2c_client *client; >> + struct device *hwmon_dev; >> + >> + /* update mutex */ >> + struct mutex update_lock; >> + >> + /* board specific parameters. */ >> + u32 clk; /* default 32kHz */ >> + >> + /* g762 register cache */ >> + bool valid; >> + unsigned long last_updated; /* in jiffies */ >> + >> + u8 set_cnt; /* RPM cmd in close loop control */ >> + u8 act_cnt; /* formula: cnt = (CLK * 30)/(rpm * P) */ >> + u8 fan_sta; /* bit 0: set when actual fan speed is more than >> + * 25% outside requested fan speed >> + * bit 1: set when no transition occurs on fan >> + * pin for 0.7s >> + */ >> + u8 set_out; /* output voltage/PWM duty in open loop control */ >> + u8 fan_cmd1; /* 0: FG_PLS_ID0 FG pulses count per revolution >> + * 0: 2 counts per revolution >> + * 1: 4 counts per revolution >> + * 1: PWM_POLARITY 1: negative_duty >> + * 0: positive_duty >> + * 2,3: [FG_CLOCK_ID0, FG_CLK_ID1] >> + * 00: Divide fan clock by 1 >> + * 01: Divide fan clock by 2 >> + * 10: Divide fan clock by 4 >> + * 11: Divide fan clock by 8 >> + * 4: FAN_MODE 1:close-loop, 0:open-loop >> + * 5: OUT_MODE 1:PWM, 0:DAC >> + * 6: DET_FAN_OOC enable "fan ooc" status >> + * 7: DET_FAN_FAIL enable "fan fail" status >> + */ >> + u8 fan_cmd2; /* 0,1: FAN_STARTV 0,1,2,3 -> 0,32,64,96 dac_code >> + * 2,3: FG_GEAR_MODE >> + * 00: div = 1 >> + * 01: div = 2 >> + * 10: div = 4 >> + * 4: Mask ALERT# (g763 only) >> + */ > > You could consider using regmap for holding this cache. > > http://elceurope2012.sched.org/event/100619b669ce5767341624253aa03659?iframe=no&w=900&sidebar=yes&bg=no#.UXdspHLQ5jM > > http://elinux.org/ELCE_Europe_2012_Presentations Interesting. As I am not yet familiar w/ regmap I would prefer having the driver accepted during merge window with current data structure and then convert it to regmap. But I will take a look (e.g. will study fca1dd03 for instance). Thanks for the pointers. >> +/* >> + * Helpers to import hardware characteristics from .dts file and overload >> + * default config values. >> + */ >> + >> +#ifdef CONFIG_OF > > Can the driver be used without device tree? Would it be simpler to > just add depends OF in the Kconfig entry? It can be used if the default params (or those configured by u-boot I guess) fit your needs. I think it would be fairly easy to extend the driver later to expose g762_config struct to allow parameters to be set w/o using OF. If someone wants to do that, I think it is better to not depend on OF in Kconfig at the moment but I have not strong argument other that that one. I'll let you decide. Cheers, a+ -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html