6.1-stable patches

added patches:
	tty-serial-imx-fix-broken-rs485.patch

diff --git a/queue-6.1/series b/queue-6.1/series
index 14528a8454b75b48f21e189a84374f4785aece59..07758be63a2693077fab2cd116f3901369ae7ec4 100644 (file)
--- a/queue-6.1/series
+++ b/queue-6.1/series
@@ -195,3 +195,4 @@ efi-libstub-fix-efi_random_alloc-to-allocate-memory-.patch
 x86-fpu-keep-xfd_state-in-sync-with-msr_ia32_xfd.patch
 efi-fix-panic-in-kdump-kernel.patch
 pwm-img-fix-pwm-clock-lookup.patch
+tty-serial-imx-fix-broken-rs485.patch

diff --git a/queue-6.1/tty-serial-imx-fix-broken-rs485.patch b/queue-6.1/tty-serial-imx-fix-broken-rs485.patch
new file mode 100644 (file)
index 0000000..33ca190
--- /dev/null
+++ b/queue-6.1/tty-serial-imx-fix-broken-rs485.patch
@@ -0,0 +1,85 @@
+From 672448ccf9b6a676f96f9352cbf91f4d35f4084a Mon Sep 17 00:00:00 2001
+From: Rickard x Andersson <rickaran@axis.com>
+Date: Wed, 21 Feb 2024 12:53:04 +0100
+Subject: tty: serial: imx: Fix broken RS485
+
+From: Rickard x Andersson <rickaran@axis.com>
+
+commit 672448ccf9b6a676f96f9352cbf91f4d35f4084a upstream.
+
+When about to transmit the function imx_uart_start_tx is called and in
+some RS485 configurations this function will call imx_uart_stop_rx. The
+problem is that imx_uart_stop_rx will enable loopback in order to
+release the RS485 bus, but when loopback is enabled transmitted data
+will just be looped to RX.
+
+This patch fixes the above problem by not enabling loopback when about
+to transmit.
+
+This driver now works well when used for RS485 half duplex master
+configurations.
+
+Fixes: 79d0224f6bf2 ("tty: serial: imx: Handle RS485 DE signal active high")
+Cc: stable <stable@kernel.org>
+Signed-off-by: Rickard x Andersson <rickaran@axis.com>
+Tested-by: Christoph Niedermaier <cniedermaier@dh-electronics.com>
+Link: https://lore.kernel.org/r/20240221115304.509811-1-rickaran@axis.com
+Signed-off-by: Christoph Niedermaier <cniedermaier@dh-electronics.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/tty/serial/imx.c |   22 ++++++++++++++++++----
+ 1 file changed, 18 insertions(+), 4 deletions(-)
+
+--- a/drivers/tty/serial/imx.c
++++ b/drivers/tty/serial/imx.c
+@@ -496,8 +496,7 @@ static void imx_uart_stop_tx(struct uart
+       }
+ }
+ 
+-/* called with port.lock taken and irqs off */
+-static void imx_uart_stop_rx(struct uart_port *port)
++static void imx_uart_stop_rx_with_loopback_ctrl(struct uart_port *port, bool loopback)
+ {
+       struct imx_port *sport = (struct imx_port *)port;
+       u32 ucr1, ucr2, ucr4, uts;
+@@ -519,7 +518,7 @@ static void imx_uart_stop_rx(struct uart
+       /* See SER_RS485_ENABLED/UTS_LOOP comment in imx_uart_probe() */
+       if (port->rs485.flags & SER_RS485_ENABLED &&
+           port->rs485.flags & SER_RS485_RTS_ON_SEND &&
+-          sport->have_rtscts && !sport->have_rtsgpio) {
++          sport->have_rtscts && !sport->have_rtsgpio && loopback) {
+               uts = imx_uart_readl(sport, imx_uart_uts_reg(sport));
+               uts |= UTS_LOOP;
+               imx_uart_writel(sport, uts, imx_uart_uts_reg(sport));
+@@ -532,6 +531,16 @@ static void imx_uart_stop_rx(struct uart
+ }
+ 
+ /* called with port.lock taken and irqs off */
++static void imx_uart_stop_rx(struct uart_port *port)
++{
++      /*
++       * Stop RX and enable loopback in order to make sure RS485 bus
++       * is not blocked. Se comment in imx_uart_probe().
++       */
++      imx_uart_stop_rx_with_loopback_ctrl(port, true);
++}
++
++/* called with port.lock taken and irqs off */
+ static void imx_uart_enable_ms(struct uart_port *port)
+ {
+       struct imx_port *sport = (struct imx_port *)port;
+@@ -719,8 +728,13 @@ static void imx_uart_start_tx(struct uar
+                               imx_uart_rts_inactive(sport, &ucr2);
+                       imx_uart_writel(sport, ucr2, UCR2);
+ 
++                      /*
++                       * Since we are about to transmit we can not stop RX
++                       * with loopback enabled because that will make our
++                       * transmitted data being just looped to RX.
++                       */
+                       if (!(port->rs485.flags & SER_RS485_RX_DURING_TX))
+-                              imx_uart_stop_rx(port);
++                              imx_uart_stop_rx_with_loopback_ctrl(port, false);
+ 
+                       sport->tx_state = WAIT_AFTER_RTS;
+