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Diffstat (limited to 'drivers/iio/adc/stm32-adc-core.c')
-rw-r--r--drivers/iio/adc/stm32-adc-core.c70
1 files changed, 40 insertions, 30 deletions
diff --git a/drivers/iio/adc/stm32-adc-core.c b/drivers/iio/adc/stm32-adc-core.c
index 804198eb0eef..bc9ebcc6508a 100644
--- a/drivers/iio/adc/stm32-adc-core.c
+++ b/drivers/iio/adc/stm32-adc-core.c
@@ -33,36 +33,9 @@
#include "stm32-adc-core.h"
-/* STM32F4 - common registers for all ADC instances: 1, 2 & 3 */
-#define STM32F4_ADC_CSR (STM32_ADCX_COMN_OFFSET + 0x00)
-#define STM32F4_ADC_CCR (STM32_ADCX_COMN_OFFSET + 0x04)
-
-/* STM32F4_ADC_CSR - bit fields */
-#define STM32F4_EOC3 BIT(17)
-#define STM32F4_EOC2 BIT(9)
-#define STM32F4_EOC1 BIT(1)
-
-/* STM32F4_ADC_CCR - bit fields */
-#define STM32F4_ADC_ADCPRE_SHIFT 16
-#define STM32F4_ADC_ADCPRE_MASK GENMASK(17, 16)
-
/* STM32 F4 maximum analog clock rate (from datasheet) */
#define STM32F4_ADC_MAX_CLK_RATE 36000000
-/* STM32H7 - common registers for all ADC instances */
-#define STM32H7_ADC_CSR (STM32_ADCX_COMN_OFFSET + 0x00)
-#define STM32H7_ADC_CCR (STM32_ADCX_COMN_OFFSET + 0x08)
-
-/* STM32H7_ADC_CSR - bit fields */
-#define STM32H7_EOC_SLV BIT(18)
-#define STM32H7_EOC_MST BIT(2)
-
-/* STM32H7_ADC_CCR - bit fields */
-#define STM32H7_PRESC_SHIFT 18
-#define STM32H7_PRESC_MASK GENMASK(21, 18)
-#define STM32H7_CKMODE_SHIFT 16
-#define STM32H7_CKMODE_MASK GENMASK(17, 16)
-
/* STM32 H7 maximum analog clock rate (from datasheet) */
#define STM32H7_ADC_MAX_CLK_RATE 36000000
@@ -72,12 +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;
@@ -271,6 +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 */
@@ -278,8 +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)
{
@@ -290,13 +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);