On Mon, Jan 29, 2007 at 06:39:50PM -0800, Andrew Morton wrote:

> > +/* Insmod parameters */
> > +I2C_CLIENT_INSMOD_1(tsl2550);
> > +
> > +static int operating_mode = 0;
> 
> The `= 0' is unneeded and undesirable.

Fixed.

> > ...
> >
> > +static int tsl2550_get_adc_value(struct i2c_client *client, int channel)
> > +{
> > +   u8 cmd = channel == 0 ? TSL2550_READ_ADC0 : TSL2550_READ_ADC1;
> > +   int timeout, ret;
> > +
> > +   /* Read ADC channel waiting at most 400ms (see data sheet for further
> > +         * info) */
> > +   for (timeout = 400; timeout > 0; timeout--) {
> > +           i2c_smbus_write_byte(client, cmd);
> > +           mdelay(1);
> > +           ret = i2c_smbus_read_byte(client);
> > +           if (ret < 0)
> > +                   return ret;
> > +           else if (ret & 0x0080)
> > +                   break;
> > +   }
> > +   if (timeout == 0)
> > +           return -EIO;
> > +   return ((u8) ret) & 0x7f;       /* remove the "valid" bit */
> > +}
> 
> eek.  Is there no way to avoid the busy-wait?  We cannot sleep here?

That's why I have to retry reading data for at most 400ms otherwise
the chip will start a new ADC conversion.

I can replace mdelay(1) with schedule_timeout(HZ/1000) but doing this
I'm not sure that just 1ms has elapesed. Also the chip has no irq
lines to use for that.

> > +/* --- LUX calculation 
> > ----------------------------------------------------- */
> > +
> > +#define    TSL2550_MAX_LUX         1846
> > +
> > +static u8 ratio_lut[] = {
> > +   100, 100, 100, 100, 100, 100, 100, 100, 
> > [snip]
> > +
> > +static u16 count_lut[] = {
> > +   0, 1, 2, 3, 4, 5, 6, 7, 
> > [snip]
> 
> These tables could perhaps be const?

Fixed.

> > +static ssize_t tsl2550_show_power_state(struct device *dev, struct 
> > device_attribute *attr, char *buf)
> 
> It's preferred to try to fit the code into an 80-col window.  (But some
> people disagree with this specifically for function definitions such as
> this).

I agree with them. :)

> Preferred coding style is
> 
>       err = i2c_detach_client(client);
>       if (err)
>               return err;
> 
> (multiple places)

Fixed.

I'm going to repost the patch after some tests.

Thanks,

Rodolfo

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