[PATCH v2] serial: 8250: 8250_omap: Clear UART_HAS_RHR_IT_DIS bit

[PATCH v2] serial: 8250: 8250_omap: Clear UART_HAS_RHR_IT_DIS bit

[Ronald Wahl]

From: Ronald Wahl <ronald.wahl@raritan.com>

This fixes commit 439c7183e5b9 ("serial: 8250: 8250_omap: Disable RX
interrupt after DMA enable") which unfortunately set the
UART_HAS_RHR_IT_DIS bit in the UART_OMAP_IER2 register and never
cleared it.

Fixes: 439c7183e5b9 ("serial: 8250: 8250_omap: Disable RX interrupt after DMA enable")
Signed-off-by: Ronald Wahl <ronald.wahl@raritan.com>
---
V2: - add Fixes: tag
    - fix author

 drivers/tty/serial/8250/8250_omap.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index ca972fd37725..c7ab2963040b 100644
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c
@@ -914,7 +914,7 @@ static void __dma_rx_do_complete(struct uart_8250_port *p)
 	if (priv->habit & UART_HAS_RHR_IT_DIS) {
 		reg = serial_in(p, UART_OMAP_IER2);
 		reg &= ~UART_OMAP_IER2_RHR_IT_DIS;
-		serial_out(p, UART_OMAP_IER2, UART_OMAP_IER2_RHR_IT_DIS);
+		serial_out(p, UART_OMAP_IER2, reg);
 	}

 	dmaengine_tx_status(rxchan, cookie, &state);
@@ -1060,7 +1060,7 @@ static int omap_8250_rx_dma(struct uart_8250_port *p)
 	if (priv->habit & UART_HAS_RHR_IT_DIS) {
 		reg = serial_in(p, UART_OMAP_IER2);
 		reg |= UART_OMAP_IER2_RHR_IT_DIS;
-		serial_out(p, UART_OMAP_IER2, UART_OMAP_IER2_RHR_IT_DIS);
+		serial_out(p, UART_OMAP_IER2, reg);
 	}

 	dma_async_issue_pending(dma->rxchan);
--
2.41.0

Re: [PATCH v2] serial: 8250: 8250_omap: Clear UART_HAS_RHR_IT_DIS bit

[Greg Kroah-Hartman]

On Tue, Oct 31, 2023 at 11:20:24AM +0100, Ronald Wahl wrote:
> From: Ronald Wahl <ronald.wahl@raritan.com>
> 
> This fixes commit 439c7183e5b9 ("serial: 8250: 8250_omap: Disable RX
> interrupt after DMA enable") which unfortunately set the
> UART_HAS_RHR_IT_DIS bit in the UART_OMAP_IER2 register and never
> cleared it.
> 
> Fixes: 439c7183e5b9 ("serial: 8250: 8250_omap: Disable RX interrupt after DMA enable")
> Signed-off-by: Ronald Wahl <ronald.wahl@raritan.com>
> ---
> V2: - add Fixes: tag
>     - fix author
> 
>  drivers/tty/serial/8250/8250_omap.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
> index ca972fd37725..c7ab2963040b 100644
> --- a/drivers/tty/serial/8250/8250_omap.c
> +++ b/drivers/tty/serial/8250/8250_omap.c
> @@ -914,7 +914,7 @@ static void __dma_rx_do_complete(struct uart_8250_port *p)
>  	if (priv->habit & UART_HAS_RHR_IT_DIS) {
>  		reg = serial_in(p, UART_OMAP_IER2);
>  		reg &= ~UART_OMAP_IER2_RHR_IT_DIS;
> -		serial_out(p, UART_OMAP_IER2, UART_OMAP_IER2_RHR_IT_DIS);
> +		serial_out(p, UART_OMAP_IER2, reg);
>  	}
> 
>  	dmaengine_tx_status(rxchan, cookie, &state);
> @@ -1060,7 +1060,7 @@ static int omap_8250_rx_dma(struct uart_8250_port *p)
>  	if (priv->habit & UART_HAS_RHR_IT_DIS) {
>  		reg = serial_in(p, UART_OMAP_IER2);
>  		reg |= UART_OMAP_IER2_RHR_IT_DIS;
> -		serial_out(p, UART_OMAP_IER2, UART_OMAP_IER2_RHR_IT_DIS);
> +		serial_out(p, UART_OMAP_IER2, reg);
>  	}
> 
>  	dma_async_issue_pending(dma->rxchan);
> --
> 2.41.0
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
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created.  Hopefully you will not take offence and will fix the problem
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You are receiving this message because of the following common error(s)
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thanks,

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