1 files changed, 40 insertions, 3 deletions

diff --git a/drivers/iio/adc/stm32-adc-core.c b/drivers/iio/adc/stm32-adc-core.c
index b0d346837a19..bc9ebcc6508a 100644
--- a/drivers/iio/adc/stm32-adc-core.c
+++ b/drivers/iio/adc/stm32-adc-core.c
@@ -45,12 +45,16 @@
  * @eoc1:	adc1 end of conversion flag in @csr
  * @eoc2:	adc2 end of conversion flag in @csr
  * @eoc3:	adc3 end of conversion flag in @csr
+ * @ier:	interrupt enable register offset for each adc
+ * @eocie_msk:	end of conversion interrupt enable mask in @ier
  */
 struct stm32_adc_common_regs {
 	u32 csr;
 	u32 eoc1_msk;
 	u32 eoc2_msk;
 	u32 eoc3_msk;
+	u32 ier;
+	u32 eocie_msk;
 };
 
 struct stm32_adc_priv;
@@ -244,6 +248,8 @@ static const struct stm32_adc_common_regs stm32f4_adc_common_regs = {
 	.eoc1_msk = STM32F4_EOC1,
 	.eoc2_msk = STM32F4_EOC2,
 	.eoc3_msk = STM32F4_EOC3,
+	.ier = STM32F4_ADC_CR1,
+	.eocie_msk = STM32F4_EOCIE,
 };
 
 /* STM32H7 common registers definitions */
@@ -251,8 +257,24 @@ static const struct stm32_adc_common_regs stm32h7_adc_common_regs = {
 	.csr = STM32H7_ADC_CSR,
 	.eoc1_msk = STM32H7_EOC_MST,
 	.eoc2_msk = STM32H7_EOC_SLV,
+	.ier = STM32H7_ADC_IER,
+	.eocie_msk = STM32H7_EOCIE,
 };
 
+static const unsigned int stm32_adc_offset[STM32_ADC_MAX_ADCS] = {
+	0, STM32_ADC_OFFSET, STM32_ADC_OFFSET * 2,
+};
+
+static unsigned int stm32_adc_eoc_enabled(struct stm32_adc_priv *priv,
+					  unsigned int adc)
+{
+	u32 ier, offset = stm32_adc_offset[adc];
+
+	ier = readl_relaxed(priv->common.base + offset + priv->cfg->regs->ier);
+
+	return ier & priv->cfg->regs->eocie_msk;
+}
+
 /* ADC common interrupt for all instances */
 static void stm32_adc_irq_handler(struct irq_desc *desc)
 {
@@ -263,13 +285,28 @@ static void stm32_adc_irq_handler(struct irq_desc *desc)
 	chained_irq_enter(chip, desc);
 	status = readl_relaxed(priv->common.base + priv->cfg->regs->csr);
 
-	if (status & priv->cfg->regs->eoc1_msk)
+	/*
+	 * End of conversion may be handled by using IRQ or DMA. There may be a
+	 * race here when two conversions complete at the same time on several
+	 * ADCs. EOC may be read 'set' for several ADCs, with:
+	 * - an ADC configured to use DMA (EOC triggers the DMA request, and
+	 *   is then automatically cleared by DR read in hardware)
+	 * - an ADC configured to use IRQs (EOCIE bit is set. The handler must
+	 *   be called in this case)
+	 * So both EOC status bit in CSR and EOCIE control bit must be checked
+	 * before invoking the interrupt handler (e.g. call ISR only for
+	 * IRQ-enabled ADCs).
+	 */
+	if (status & priv->cfg->regs->eoc1_msk &&
+	    stm32_adc_eoc_enabled(priv, 0))
 		generic_handle_irq(irq_find_mapping(priv->domain, 0));
 
-	if (status & priv->cfg->regs->eoc2_msk)
+	if (status & priv->cfg->regs->eoc2_msk &&
+	    stm32_adc_eoc_enabled(priv, 1))
 		generic_handle_irq(irq_find_mapping(priv->domain, 1));
 
-	if (status & priv->cfg->regs->eoc3_msk)
+	if (status & priv->cfg->regs->eoc3_msk &&
+	    stm32_adc_eoc_enabled(priv, 2))
 		generic_handle_irq(irq_find_mapping(priv->domain, 2));
 
 	chained_irq_exit(chip, desc);