[nrf fromlist] drivers: serial: nrfx_uarte: Fix low power mode for interrupt driven API

nordic-krch · nordic-krch · commit a36d97e9ffe8 · 2024-11-20T09:06:38.000+01:00
Low power mode for non-asynchronous API case is only available when
RX is not used (RX pin is not defined). In that case TX starting
function was using uarte_enable_locked() which tracks if UARTE is
used by TX or RX and TXSTOPPED interrupt was disabling UARTE
unconditionally. Because of that following attempt to TX start
was assuming that UARTE is already enabled when it was disabled.
Fixing it by using uarte_disable_locked function in TXSTOPPED
handling.

Upstream PR #: 81631

Signed-off-by: Krzysztof Chruściński &lt;krzysztof.chruscinski@nordicsemi.no&gt;
diff --git a/drivers/serial/uart_nrfx_uarte.c b/drivers/serial/uart_nrfx_uarte.c
@@ -398,7 +398,7 @@ static void uarte_nrfx_isr_int(const void *arg)
 			data->flags &= ~UARTE_FLAG_POLL_OUT;
 			pm_device_runtime_put(dev);
 		} else {
-			nrf_uarte_disable(uarte);
+			uarte_disable_locked(dev, UARTE_FLAG_LOW_POWER_TX);
 		}
 
 #ifdef UARTE_INTERRUPT_DRIVEN

Original file line number	Diff line number	Diff line change
`@@ -398,7 +398,7 @@ static void uarte_nrfx_isr_int(const void *arg)`
`398`	`398`	`data->flags &= ~UARTE_FLAG_POLL_OUT;`
`399`	`399`	`pm_device_runtime_put(dev);`
`400`	`400`	`} else {`
`401`		`- nrf_uarte_disable(uarte);`
	`401`	`+ uarte_disable_locked(dev, UARTE_FLAG_LOW_POWER_TX);`
`402`	`402`	`}`
`403`	`403`
`404`	`404`	`#ifdef UARTE_INTERRUPT_DRIVEN`