Commit ff6b1513 authored Oct 31, 2023 by Ronald Wahl Committed by sanglipeng Apr 24, 2024

serial: 8250: 8250_omap: Clear UART_HAS_RHR_IT_DIS bit

stable inclusion
from stable-v5.10.204
commit b74ace5dec53c89bcda010204a5b6ec2589fa673
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I9J4PL

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b74ace5dec53c89bcda010204a5b6ec2589fa673



--------------------------------

commit 8973ab7a2441b286218f4a5c4c33680e2f139996 upstream.

This fixes commit 439c7183 ("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.

Cc: stable@vger.kernel.org
Fixes: 439c7183 ("serial: 8250: 8250_omap: Disable RX interrupt after DMA enable")
Signed-off-by: Ronald Wahl <ronald.wahl@raritan.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20231031110909.11695-1-rwahl@gmx.de


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>

parent c113dfa8

drivers/tty/serial/8250/8250_omap.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -844,7 +844,7 @@ 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);
		@@ -986,7 +986,7 @@ 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);