[PATCH] leds: Add LED class driver for regulator driven LEDs.

Antonio Ospite ospite at studenti.unina.it
Wed Dec 2 15:31:31 EST 2009


On Wed, 02 Dec 2009 18:23:55 +0000
Liam Girdwood <lrg at slimlogic.co.uk> wrote:

> On Wed, 2009-12-02 at 18:40 +0100, Antonio Ospite wrote:
> > This driver provides an interface for controlling LEDs (or vibrators)
> > connected to PMICs for which there is a regulator framework driver.
> > 
> > This driver can be used, for instance, to control vibrator on all Motorola EZX
> > phones using the pcap-regulator driver services.
> > 
> > Signed-off-by: Antonio Ospite <ospite at studenti.unina.it>
> 
> Some very minor points below.
> 

Thanks for reviewing the code.

[...]
> > +
> > +static void led_work(struct work_struct *work)
> > +{
> > +	struct regulator_led *led;
> > +	int voltage;
> > +	int ret;
> > +
> > +	led = container_of(work, struct regulator_led, work);
> > +
> > +	mutex_lock(&led->mutex);
> > +
> > +	if (led->value == 0) {
> 
> LED_OFF instead of 0 here ?
>

Ok.

> > +		regulator_led_disable(led);
> > +		goto out;
> > +	}
> > +
> > +	voltage = led_regulator_get_vdd(led->vcc, led->value);
> > +	dev_dbg(led->cdev.dev, "brightness: %d voltage: %d",
> > +			led->value, voltage);
> > +
> > +	ret = regulator_set_voltage(led->vcc, voltage, voltage);
> > +	if (ret != 0)
> > +		dev_err(led->cdev.dev, "Failed to set voltage %d: %d\n",
> > +			voltage, ret);
> 
> Some regulators may not support voltage change (via hw design or
> constraints) so set_voltage() will fail. We probably want to handle this
> regulator type so we don't call set_voltage().
>

Ok, I'll read more about the regulator framework to find out how to
check regulator capabilities.

> > +
> > +	regulator_led_enable(led);
> > +
> > +out:
> > +	mutex_unlock(&led->mutex);
> > +}
> > +
[...]
> > +static int regulator_led_probe(struct platform_device *pdev)
> > +{
> > +	struct led_regulator_platform_data *pdata = pdev->dev.platform_data;
> > +	struct regulator_led *led;
> > +	struct regulator *vcc;
> > +	int ret;
> > +
> > +	if (pdata == NULL) {
> > +		dev_err(&pdev->dev, "no platform data\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	vcc = regulator_get(&pdev->dev, pdata->supply);
> > +	if (IS_ERR(vcc)) {
> > +		dev_err(&pdev->dev, "Cannot get vcc for %s\n", pdata->name);
> > +		return PTR_ERR(vcc);;
> 
> double ;; here
>

Thanks.

[...]

Regards,
   Antonio 

-- 
Antonio Ospite
http://ao2.it

PGP public key ID: 0x4553B001

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