iio: adc: stm32: Fix ADCs iteration in irq handler

The irq handler was only checking the mask for the first ADCs in the case of the
F4 and H7 generation, since it was iterating up to the num_irq value. This patch add
the maximum number of ADC in the common register, which map to the number of entries of
eoc_msk and ovr_msk in stm32_adc_common_regs. This allow the handler to check all ADCs in
that module.

Tested on a STM32F429NIH6.

Fixes: 695e2f5 ("iio: adc: stm32-adc: fix a regression when using dma and irq")
Signed-off-by: Yannick Brosseau <yannick.brosseau@gmail.com>
Reviewed-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Link: https://lore.kernel.org/r/20220516203939.3498673-2-yannick.brosseau@gmail.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/adc/stm32-adc-core.c

@@ -64,13 +64,15 @@ struct stm32_adc_priv;
  * @max_clk_rate_hz: maximum analog clock rate (Hz, from datasheet)
  * @has_syscfg: SYSCFG capability flags
  * @num_irqs:	number of interrupt lines
+ * @num_adcs:   maximum number of ADC instances in the common registers
  */
 struct stm32_adc_priv_cfg {
 	const struct stm32_adc_common_regs *regs;
 	int (*clk_sel)(struct platform_device *, struct stm32_adc_priv *);
 	u32 max_clk_rate_hz;
 	unsigned int has_syscfg;
 	unsigned int num_irqs;
+	unsigned int num_adcs;
 };
 
 /**
@@ -352,7 +354,7 @@ static void stm32_adc_irq_handler(struct irq_desc *desc)
 	 * before invoking the interrupt handler (e.g. call ISR only for
 	 * IRQ-enabled ADCs).
 	 */
-	for (i = 0; i < priv->cfg->num_irqs; i++) {
+	for (i = 0; i < priv->cfg->num_adcs; i++) {
 		if ((status & priv->cfg->regs->eoc_msk[i] &&
 		     stm32_adc_eoc_enabled(priv, i)) ||
 		     (status & priv->cfg->regs->ovr_msk[i]))
@@ -792,6 +794,7 @@ static const struct stm32_adc_priv_cfg stm32f4_adc_priv_cfg = {
 	.clk_sel = stm32f4_adc_clk_sel,
 	.max_clk_rate_hz = 36000000,
 	.num_irqs = 1,
+	.num_adcs = 3,
 };
 
 static const struct stm32_adc_priv_cfg stm32h7_adc_priv_cfg = {
@@ -800,6 +803,7 @@ static const struct stm32_adc_priv_cfg stm32h7_adc_priv_cfg = {
 	.max_clk_rate_hz = 36000000,
 	.has_syscfg = HAS_VBOOSTER,
 	.num_irqs = 1,
+	.num_adcs = 2,
 };
 
 static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
@@ -808,6 +812,7 @@ static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
 	.max_clk_rate_hz = 40000000,
 	.has_syscfg = HAS_VBOOSTER | HAS_ANASWVDD,
 	.num_irqs = 2,
+	.num_adcs = 2,
 };
 
 static const struct of_device_id stm32_adc_of_match[] = {