On Wed, Oct 16, 2019 at 03:43:46PM +0530, Kiran Gunda wrote:
> The auto string detection algorithm checks if the current WLED
> sink configuration is valid. It tries enabling every sink and
> checks if the OVP fault is observed. Based on this information
> it detects and enables the valid sink configuration.
> Auto calibration will be triggered when the OVP fault interrupts
> are seen frequently thereby it tries to fix the sink configuration.
>
> The auto-detection also kicks in when the connected LED string
> of the display-backlight malfunctions (because of damage) and
> requires the damaged string to be turned off to prevent the
> complete panel and/or board from being damaged.
>
> Signed-off-by: Kiran Gunda <kgunda@xxxxxxxxxxxxxx>
It's a complex bit of code but I'm OK with it in principle. Everything
below is about small details and/or nitpicking.
> +static void wled_ovp_work(struct work_struct *work)
> +{
> + struct wled *wled = container_of(work,
> + struct wled, ovp_work.work);
> + enable_irq(wled->ovp_irq);
> +}
> +
A bit of commenting about why we have to wait 10ms before enabling the
OVP interrupt would be appreciated.
> +static irqreturn_t wled_ovp_irq_handler(int irq, void *_wled)
> +{
> + struct wled *wled = _wled;
> + int rc;
> + u32 int_sts, fault_sts;
> +
> + rc = regmap_read(wled->regmap,
> + wled->ctrl_addr + WLED3_CTRL_REG_INT_RT_STS, &int_sts);
> + if (rc < 0) {
> + dev_err(wled->dev, "Error in reading WLED3_INT_RT_STS rc=%d\n",
> + rc);
> + return IRQ_HANDLED;
> + }
> +
> + rc = regmap_read(wled->regmap, wled->ctrl_addr +
> + WLED3_CTRL_REG_FAULT_STATUS, &fault_sts);
> + if (rc < 0) {
> + dev_err(wled->dev, "Error in reading WLED_FAULT_STATUS rc=%d\n",
> + rc);
> + return IRQ_HANDLED;
> + }
> +
> + if (fault_sts &
> + (WLED3_CTRL_REG_OVP_FAULT_BIT | WLED3_CTRL_REG_ILIM_FAULT_BIT))
> + dev_dbg(wled->dev, "WLED OVP fault detected, int_sts=%x fault_sts= %x\n",
> + int_sts, fault_sts);
> +
> + if (fault_sts & WLED3_CTRL_REG_OVP_FAULT_BIT) {
> + mutex_lock(&wled->lock);
> + disable_irq_nosync(wled->ovp_irq);
We're currently running the threaded ISR for this irq. Do we really need
to disable it?
> +
> + if (wled_auto_detection_required(wled))
> + wled_auto_string_detection(wled);
> +
> + enable_irq(wled->ovp_irq);
> +
> + mutex_unlock(&wled->lock);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
Snip.
> +static int wled_remove(struct platform_device *pdev)
> +{
> + struct wled *wled = dev_get_drvdata(&pdev->dev);
> +
> + cancel_delayed_work_sync(&wled->ovp_work);
> + mutex_destroy(&wled->lock);
Have the irq handlers been disabled at this point?
Also, if you want to destroy the mutex shouldn't that code be
introduced in the same patch that introduces the mutex?
> +
> + return 0;
> +}
Daniel.
