On Thu 16 Nov 04:18 PST 2017, Kiran Gunda wrote: > WLED peripheral has over voltage protection(OVP) circuitry and the OVP > fault is notified through an interrupt. Though this fault condition rising > is due to an incorrect hardware configuration is mitigated in the hardware, > it still needs to be detected and handled. Add support for it. > > When WLED module is enabled, keep OVP fault interrupt disabled for 10 ms to > account for soft start delay. > > Signed-off-by: Kiran Gunda <kgunda@xxxxxxxxxxxxxx> > --- > .../bindings/leds/backlight/qcom-spmi-wled.txt | 7 +- > drivers/video/backlight/qcom-spmi-wled.c | 83 ++++++++++++++++++++++ > 2 files changed, 87 insertions(+), 3 deletions(-) > > diff --git a/Documentation/devicetree/bindings/leds/backlight/qcom-spmi-wled.txt b/Documentation/devicetree/bindings/leds/backlight/qcom-spmi-wled.txt > index 768608c..d39ee93 100644 > --- a/Documentation/devicetree/bindings/leds/backlight/qcom-spmi-wled.txt > +++ b/Documentation/devicetree/bindings/leds/backlight/qcom-spmi-wled.txt > @@ -92,7 +92,7 @@ The PMIC is connected to the host processor via SPMI bus. > Usage: optional > Value type: <string> > Definition: Interrupt names associated with the interrupts. > - Must be "sc-irq". > + Currently supported interrupts are "sc-irq" and "ovp-irq". > As before, we know this is an IRQ, so omit the -irq from the name. [..] > diff --git a/drivers/video/backlight/qcom-spmi-wled.c b/drivers/video/backlight/qcom-spmi-wled.c [..] > @@ -115,6 +123,28 @@ static int qcom_wled_module_enable(struct qcom_wled *wled, int val) > rc = regmap_update_bits(wled->regmap, wled->ctrl_addr + > QCOM_WLED_CTRL_MOD_ENABLE, QCOM_WLED_CTRL_MOD_EN_MASK, > val << QCOM_WLED_CTRL_MODULE_EN_SHIFT); > + if (rc < 0) > + return rc; > + /* > + * Wait for at least 10ms before enabling OVP fault interrupt after > + * enabling the module so that soft start is completed. Keep the OVP > + * interrupt disabled when the module is disabled. > + */ > + if (val) { > + usleep_range(QCOM_WLED_SOFT_START_DLY_US, > + QCOM_WLED_SOFT_START_DLY_US + 1000); This is sleeping in the brightness/enable code path, can you schedule_delayed_work() instead to not block this code path unnecessarily? > + > + if (wled->cfg.ovp_irq > 0 && wled->ovp_irq_disabled) { > + enable_irq(wled->cfg.ovp_irq); > + wled->ovp_irq_disabled = false; > + } > + } else { > + if (wled->cfg.ovp_irq > 0 && !wled->ovp_irq_disabled) { > + disable_irq(wled->cfg.ovp_irq); > + wled->ovp_irq_disabled = true; > + } > + } > + > return rc; > } > > @@ -264,12 +294,42 @@ static irqreturn_t qcom_wled_sc_irq_handler(int irq, void *_wled) > return IRQ_HANDLED; > } > > +static irqreturn_t qcom_wled_ovp_irq_handler(int irq, void *_wled) > +{ > + struct qcom_wled *wled = _wled; > + int rc; > + u32 int_sts, fault_sts; > + > + rc = regmap_read(wled->regmap, > + wled->ctrl_addr + QCOM_WLED_CTRL_INT_RT_STS, &int_sts); > + if (rc < 0) { > + pr_err("Error in reading WLED_INT_RT_STS rc=%d\n", rc); > + return IRQ_HANDLED; > + } > + > + rc = regmap_read(wled->regmap, wled->ctrl_addr + > + QCOM_WLED_CTRL_FAULT_STATUS, &fault_sts); > + if (rc < 0) { > + pr_err("Error in reading WLED_FAULT_STATUS rc=%d\n", rc); > + return IRQ_HANDLED; > + } > + > + if (fault_sts & > + (QCOM_WLED_CTRL_OVP_FAULT_BIT | QCOM_WLED_CTRL_ILIM_FAULT_BIT)) > + pr_err("WLED OVP fault detected, int_sts=%x fault_sts= %x\n", > + int_sts, fault_sts); All this function does is print things to the log. When is this information consumed and by whom? dev_dbg() instead? > + > + return IRQ_HANDLED; > +} > + > static int qcom_wled_setup(struct qcom_wled *wled) > { > int rc, temp, i; > u8 sink_en = 0; > + u32 val; > u8 string_cfg = wled->cfg.string_cfg; > int sc_irq = wled->cfg.sc_irq; > + int ovp_irq = wled->cfg.ovp_irq; > > rc = regmap_update_bits(wled->regmap, > wled->ctrl_addr + QCOM_WLED_CTRL_OVP, > @@ -367,6 +427,25 @@ static int qcom_wled_setup(struct qcom_wled *wled) > } > } > > + if (ovp_irq >= 0) { As with the previous patch. [..] > @@ -539,6 +618,10 @@ static int qcom_wled_configure(struct qcom_wled *wled, struct device *dev) [..] > + wled->cfg.ovp_irq = platform_get_irq_byname(wled->pdev, "ovp-irq"); > + if (wled->cfg.ovp_irq < 0) > + dev_dbg(&wled->pdev->dev, "ovp irq is not used\n"); > + Regards, Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html