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path: root/drivers/iio/adc/stm32-adc.c
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Diffstat (limited to 'drivers/iio/adc/stm32-adc.c')
-rw-r--r--drivers/iio/adc/stm32-adc.c55
1 files changed, 53 insertions, 2 deletions
diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c
index 3b291d72701c..5f05bf9f16ea 100644
--- a/drivers/iio/adc/stm32-adc.c
+++ b/drivers/iio/adc/stm32-adc.c
@@ -117,7 +117,9 @@ struct stm32_adc_regs {
* struct stm32_adc_regspec - stm32 registers definition
* @dr: data register offset
* @ier_eoc: interrupt enable register & eocie bitfield
+ * @ier_ovr: interrupt enable register & overrun bitfield
* @isr_eoc: interrupt status register & eoc bitfield
+ * @isr_ovr: interrupt status register & overrun bitfield
* @sqr: reference to sequence registers array
* @exten: trigger control register & bitfield
* @extsel: trigger selection register & bitfield
@@ -128,7 +130,9 @@ struct stm32_adc_regs {
struct stm32_adc_regspec {
const u32 dr;
const struct stm32_adc_regs ier_eoc;
+ const struct stm32_adc_regs ier_ovr;
const struct stm32_adc_regs isr_eoc;
+ const struct stm32_adc_regs isr_ovr;
const struct stm32_adc_regs *sqr;
const struct stm32_adc_regs exten;
const struct stm32_adc_regs extsel;
@@ -337,7 +341,9 @@ static const unsigned int stm32f4_adc_smp_cycles[STM32_ADC_MAX_SMP + 1] = {
static const struct stm32_adc_regspec stm32f4_adc_regspec = {
.dr = STM32F4_ADC_DR,
.ier_eoc = { STM32F4_ADC_CR1, STM32F4_EOCIE },
+ .ier_ovr = { STM32F4_ADC_CR1, STM32F4_OVRIE },
.isr_eoc = { STM32F4_ADC_SR, STM32F4_EOC },
+ .isr_ovr = { STM32F4_ADC_SR, STM32F4_OVR },
.sqr = stm32f4_sq,
.exten = { STM32F4_ADC_CR2, STM32F4_EXTEN_MASK, STM32F4_EXTEN_SHIFT },
.extsel = { STM32F4_ADC_CR2, STM32F4_EXTSEL_MASK,
@@ -429,7 +435,9 @@ static const unsigned int stm32h7_adc_smp_cycles[STM32_ADC_MAX_SMP + 1] = {
static const struct stm32_adc_regspec stm32h7_adc_regspec = {
.dr = STM32H7_ADC_DR,
.ier_eoc = { STM32H7_ADC_IER, STM32H7_EOCIE },
+ .ier_ovr = { STM32H7_ADC_IER, STM32H7_OVRIE },
.isr_eoc = { STM32H7_ADC_ISR, STM32H7_EOC },
+ .isr_ovr = { STM32H7_ADC_ISR, STM32H7_OVR },
.sqr = stm32h7_sq,
.exten = { STM32H7_ADC_CFGR, STM32H7_EXTEN_MASK, STM32H7_EXTEN_SHIFT },
.extsel = { STM32H7_ADC_CFGR, STM32H7_EXTSEL_MASK,
@@ -506,6 +514,18 @@ static void stm32_adc_conv_irq_disable(struct stm32_adc *adc)
adc->cfg->regs->ier_eoc.mask);
}
+static void stm32_adc_ovr_irq_enable(struct stm32_adc *adc)
+{
+ stm32_adc_set_bits(adc, adc->cfg->regs->ier_ovr.reg,
+ adc->cfg->regs->ier_ovr.mask);
+}
+
+static void stm32_adc_ovr_irq_disable(struct stm32_adc *adc)
+{
+ stm32_adc_clr_bits(adc, adc->cfg->regs->ier_ovr.reg,
+ adc->cfg->regs->ier_ovr.mask);
+}
+
static void stm32_adc_set_res(struct stm32_adc *adc)
{
const struct stm32_adc_regs *res = &adc->cfg->regs->res;
@@ -1205,6 +1225,19 @@ static int stm32_adc_read_raw(struct iio_dev *indio_dev,
}
}
+static irqreturn_t stm32_adc_threaded_isr(int irq, void *data)
+{
+ struct stm32_adc *adc = data;
+ struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+ const struct stm32_adc_regspec *regs = adc->cfg->regs;
+ u32 status = stm32_adc_readl(adc, regs->isr_eoc.reg);
+
+ if (status & regs->isr_ovr.mask)
+ dev_err(&indio_dev->dev, "Overrun, stopping: restart needed\n");
+
+ return IRQ_HANDLED;
+}
+
static irqreturn_t stm32_adc_isr(int irq, void *data)
{
struct stm32_adc *adc = data;
@@ -1212,6 +1245,19 @@ static irqreturn_t stm32_adc_isr(int irq, void *data)
const struct stm32_adc_regspec *regs = adc->cfg->regs;
u32 status = stm32_adc_readl(adc, regs->isr_eoc.reg);
+ if (status & regs->isr_ovr.mask) {
+ /*
+ * Overrun occurred on regular conversions: data for wrong
+ * channel may be read. Unconditionally disable interrupts
+ * to stop processing data and print error message.
+ * Restarting the capture can be done by disabling, then
+ * re-enabling it (e.g. write 0, then 1 to buffer/enable).
+ */
+ stm32_adc_ovr_irq_disable(adc);
+ stm32_adc_conv_irq_disable(adc);
+ return IRQ_WAKE_THREAD;
+ }
+
if (status & regs->isr_eoc.mask) {
/* Reading DR also clears EOC status flag */
adc->buffer[adc->bufi] = stm32_adc_readw(adc, regs->dr);
@@ -1441,6 +1487,8 @@ static int __stm32_adc_buffer_postenable(struct iio_dev *indio_dev)
/* Reset adc buffer index */
adc->bufi = 0;
+ stm32_adc_ovr_irq_enable(adc);
+
if (!adc->dma_chan)
stm32_adc_conv_irq_enable(adc);
@@ -1481,6 +1529,8 @@ static void __stm32_adc_buffer_predisable(struct iio_dev *indio_dev)
if (!adc->dma_chan)
stm32_adc_conv_irq_disable(adc);
+ stm32_adc_ovr_irq_disable(adc);
+
if (adc->dma_chan)
dmaengine_terminate_sync(adc->dma_chan);
@@ -1818,8 +1868,9 @@ static int stm32_adc_probe(struct platform_device *pdev)
if (adc->irq < 0)
return adc->irq;
- ret = devm_request_irq(&pdev->dev, adc->irq, stm32_adc_isr,
- 0, pdev->name, adc);
+ ret = devm_request_threaded_irq(&pdev->dev, adc->irq, stm32_adc_isr,
+ stm32_adc_threaded_isr,
+ 0, pdev->name, adc);
if (ret) {
dev_err(&pdev->dev, "failed to request IRQ\n");
return ret;