RE: [PATCH v4 3/5] leds-lm3530: support pwm input mode

[Kim, Milo]

> -----Original Message-----
> From: Andrew Morton [mailto:akpm@xxxxxxxxxxxxxxxxxxxx]
> Sent: Wednesday, February 08, 2012 7:55 AM
> To: Kim, Milo
> Cc: Linus Walleij; shreshthakumar.sahu@xxxxxxxxxxxxxx;
> rpurdie@xxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v4 3/5] leds-lm3530: support pwm input mode
> 
> On Mon, 6 Feb 2012 21:14:21 -0800
> "Kim, Milo" <Milo.Kim@xxxxxx> wrote:
> 
> > * add 'struct lm3530_pwm_data' in the platform data
> >   The pwm data is the platform specific functions which generate the
> pwm.
> >   The pwm data is only valid when brightness is pwm input mode.
> >   Functions should be implemented by the pwm driver.
> >   pwm_set_intensity() : set duty of pwm.
> >   pwm_get_intensity() : get current the brightness.
> >
> > * brightness control by pwm
> >   If the control mode is pwm, then brightness is changed by the duty
> of pwm.
> >   So pwm platform function should be called in
> lm3530_brightness_set().
> >
> > * do not update brightness register when pwm input mode
> >   In pwm input mode, brightness register is not used.
> >   If any value is updated in this register, then the led will be off.
> >
> > * when input mode is changed, set duty of pwm to 0 if unnecessary.
> >
> > * patch base version : kernel 3.2.4
> >
> >
> > ...
> >
> > @@ -327,14 +344,11 @@ static ssize_t lm3530_mode_set(struct device
> *dev, struct device_attribute
> >  		return -EINVAL;
> >  	}
> >
> > -	if (mode == LM3530_BL_MODE_MANUAL)
> > -		drvdata->mode = LM3530_BL_MODE_MANUAL;
> > -	else if (mode == LM3530_BL_MODE_ALS)
> > -		drvdata->mode = LM3530_BL_MODE_ALS;
> > -	else if (mode == LM3530_BL_MODE_PWM) {
> > -		dev_err(dev, "PWM mode not supported\n");
> > -		return -EINVAL;
> > -	}
> > +	drvdata->mode = mode;
> > +
> > +	/* set pwm to low if unnecessary */
> > +	if (mode != LM3530_BL_MODE_PWM && pwm->pwm_set_intensity)
> > +		pwm->pwm_set_intensity(0, max_brightness);
> 
> lm3530_mode_set() has no local variable "pwm" and has no local variable
> "brightness".

Local variable "pwm" was added in this patch.
[PATCH v4 3/5] leds-lm3530: support pwm input mode

@@ -255,6 +265,9 @@ static void lm3530_brightness_set(struct
 	int err;
 	struct lm3530_data *drvdata =
 	    container_of(led_cdev, struct lm3530_data, led_dev);
+	struct lm3530_platform_data *pdata = drvdata->pdata;
+	struct lm3530_pwm_data *pwm = &pdata->pwm_data;
+	u8 max_brightness = led_cdev->max_brightness;

And I can see the same code in your mm tree mail.

> 
> I see now that you prepared the patches against 3.2.4, which might
> contribute to this problem, but I don't see how the patches could work
> in 3.2 either.  Perhaps 3.2.4 is significantly different from 3.2.
> 

For the leds-lm3530 driver, there is no difference between 3.2 and 3.2.4.
I'm curious what happened to the patch. Can I have any message from your working tree ?

Thanks & BR
Milo -

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