This is a note to let you know that I've just added the patch titled
serial: 8250_of: Drop quirk fot NPCM from 8250_port
to the 6.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
serial-8250_of-drop-quirk-fot-npcm-from-8250_port.patch
and it can be found in the queue-6.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 342f7cedb757dd05f1d8bcdebddd821d2013a048
Author: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Date: Thu Feb 15 16:50:08 2024 +0200
serial: 8250_of: Drop quirk fot NPCM from 8250_port
[ Upstream commit cd0eb354d441488feed6685adbeb1acd45db1b8d ]
We are not supposed to spread quirks in 8250_port module especially
when we have a separate driver for the hardware in question.
Move quirk from generic module to the driver that uses it.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240215145029.581389-1-andriy.shevchenko@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c
index 34f17a9785e79..9dcc17e332690 100644
--- a/drivers/tty/serial/8250/8250_of.c
+++ b/drivers/tty/serial/8250/8250_of.c
@@ -4,7 +4,10 @@
*
* Copyright (C) 2006 Arnd Bergmann <arnd@xxxxxxxx>, IBM Corp.
*/
+
+#include <linux/bits.h>
#include <linux/console.h>
+#include <linux/math.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/serial_core.h>
@@ -25,6 +28,36 @@ struct of_serial_info {
int line;
};
+/* Nuvoton NPCM timeout register */
+#define UART_NPCM_TOR 7
+#define UART_NPCM_TOIE BIT(7) /* Timeout Interrupt Enable */
+
+static int npcm_startup(struct uart_port *port)
+{
+ /*
+ * Nuvoton calls the scratch register 'UART_TOR' (timeout
+ * register). Enable it, and set TIOC (timeout interrupt
+ * comparator) to be 0x20 for correct operation.
+ */
+ serial_port_out(port, UART_NPCM_TOR, UART_NPCM_TOIE | 0x20);
+
+ return serial8250_do_startup(port);
+}
+
+/* Nuvoton NPCM UARTs have a custom divisor calculation */
+static unsigned int npcm_get_divisor(struct uart_port *port, unsigned int baud,
+ unsigned int *frac)
+{
+ return DIV_ROUND_CLOSEST(port->uartclk, 16 * baud + 2) - 2;
+}
+
+static int npcm_setup(struct uart_port *port)
+{
+ port->get_divisor = npcm_get_divisor;
+ port->startup = npcm_startup;
+ return 0;
+}
+
/*
* Fill a struct uart_port for a given device node
*/
@@ -164,10 +197,17 @@ static int of_platform_serial_setup(struct platform_device *ofdev,
switch (type) {
case PORT_RT2880:
ret = rt288x_setup(port);
- if (ret)
- goto err_pmruntime;
+ break;
+ case PORT_NPCM:
+ ret = npcm_setup(port);
+ break;
+ default:
+ /* Nothing to do */
+ ret = 0;
break;
}
+ if (ret)
+ goto err_pmruntime;
if (IS_REACHABLE(CONFIG_SERIAL_8250_FSL) &&
(of_device_is_compatible(np, "fsl,ns16550") ||
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 1d65055dde276..c0c34e410c581 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -38,10 +38,6 @@
#include "8250.h"
-/* Nuvoton NPCM timeout register */
-#define UART_NPCM_TOR 7
-#define UART_NPCM_TOIE BIT(7) /* Timeout Interrupt Enable */
-
/*
* Debugging.
*/
@@ -2229,15 +2225,6 @@ int serial8250_do_startup(struct uart_port *port)
UART_DA830_PWREMU_MGMT_FREE);
}
- if (port->type == PORT_NPCM) {
- /*
- * Nuvoton calls the scratch register 'UART_TOR' (timeout
- * register). Enable it, and set TIOC (timeout interrupt
- * comparator) to be 0x20 for correct operation.
- */
- serial_port_out(port, UART_NPCM_TOR, UART_NPCM_TOIE | 0x20);
- }
-
#ifdef CONFIG_SERIAL_8250_RSA
/*
* If this is an RSA port, see if we can kick it up to the
@@ -2539,15 +2526,6 @@ static void serial8250_shutdown(struct uart_port *port)
serial8250_do_shutdown(port);
}
-/* Nuvoton NPCM UARTs have a custom divisor calculation */
-static unsigned int npcm_get_divisor(struct uart_8250_port *up,
- unsigned int baud)
-{
- struct uart_port *port = &up->port;
-
- return DIV_ROUND_CLOSEST(port->uartclk, 16 * baud + 2) - 2;
-}
-
static unsigned int serial8250_do_get_divisor(struct uart_port *port,
unsigned int baud,
unsigned int *frac)
@@ -2592,8 +2570,6 @@ static unsigned int serial8250_do_get_divisor(struct uart_port *port,
quot = 0x8001;
else if (magic_multiplier && baud >= port->uartclk / 12)
quot = 0x8002;
- else if (up->port.type == PORT_NPCM)
- quot = npcm_get_divisor(up, baud);
else
quot = uart_get_divisor(port, baud);
