mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-22 15:02:32 +00:00
8c405cdccc
The patches were generated from the RPi repo with the following command: git format-patch v6.6.34..rpi-6.1.y Some patches needed rebasing and, as usual, the applied and reverted, wireless drivers, Github workflows, READMEs and defconfigs patches were removed. Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
104 lines
3.6 KiB
Diff
104 lines
3.6 KiB
Diff
From 14f02e6c4b2937eb7bcbbb7e5a5e661d37475e3d Mon Sep 17 00:00:00 2001
|
|
From: Phil Elwell <phil@raspberrypi.com>
|
|
Date: Mon, 24 Apr 2023 11:48:31 +0100
|
|
Subject: [PATCH 0440/1085] serial: 8250: Add NOMSI bug for bcm2835aux
|
|
|
|
The BCM2835 mini-UART has no modem status interrupt, causing all
|
|
transmission to stop, never to use, if a speed change ever happens
|
|
while the CTS signal is high.
|
|
|
|
Add a simple polling mechanism in order to allow recovery in that
|
|
situation.
|
|
|
|
Signed-off-by: Phil Elwell <phil@raspberrypi.com>
|
|
---
|
|
drivers/tty/serial/8250/8250.h | 1 +
|
|
drivers/tty/serial/8250/8250_bcm2835aux.c | 1 +
|
|
drivers/tty/serial/8250/8250_core.c | 15 +++++++++++++++
|
|
drivers/tty/serial/8250/8250_port.c | 9 +++++++++
|
|
4 files changed, 26 insertions(+)
|
|
|
|
--- a/drivers/tty/serial/8250/8250.h
|
|
+++ b/drivers/tty/serial/8250/8250.h
|
|
@@ -92,6 +92,7 @@ struct serial8250_config {
|
|
#define UART_BUG_NOMSR BIT(2) /* UART has buggy MSR status bits (Au1x00) */
|
|
#define UART_BUG_THRE BIT(3) /* UART has buggy THRE reassertion */
|
|
#define UART_BUG_TXRACE BIT(5) /* UART Tx fails to set remote DR */
|
|
+#define UART_BUG_NOMSI BIT(6) /* UART has no modem status interrupt */
|
|
|
|
|
|
#ifdef CONFIG_SERIAL_8250_SHARE_IRQ
|
|
--- a/drivers/tty/serial/8250/8250_bcm2835aux.c
|
|
+++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
|
|
@@ -109,6 +109,7 @@ static int bcm2835aux_serial_probe(struc
|
|
UPF_SKIP_TEST | UPF_IOREMAP;
|
|
up.port.rs485_config = serial8250_em485_config;
|
|
up.port.rs485_supported = serial8250_em485_supported;
|
|
+ up.bugs |= UART_BUG_NOMSI;
|
|
up.rs485_start_tx = bcm2835aux_rs485_start_tx;
|
|
up.rs485_stop_tx = bcm2835aux_rs485_stop_tx;
|
|
|
|
--- a/drivers/tty/serial/8250/8250_core.c
|
|
+++ b/drivers/tty/serial/8250/8250_core.c
|
|
@@ -253,6 +253,18 @@ static void serial8250_timeout(struct ti
|
|
mod_timer(&up->timer, jiffies + uart_poll_timeout(&up->port));
|
|
}
|
|
|
|
+static void serial8250_cts_poll_timeout(struct timer_list *t)
|
|
+{
|
|
+ struct uart_8250_port *up = from_timer(up, t, timer);
|
|
+ unsigned long flags;
|
|
+
|
|
+ spin_lock_irqsave(&up->port.lock, flags);
|
|
+ serial8250_modem_status(up);
|
|
+ spin_unlock_irqrestore(&up->port.lock, flags);
|
|
+ if (up->port.hw_stopped)
|
|
+ mod_timer(&up->timer, jiffies + 1);
|
|
+}
|
|
+
|
|
static void serial8250_backup_timeout(struct timer_list *t)
|
|
{
|
|
struct uart_8250_port *up = from_timer(up, t, timer);
|
|
@@ -315,6 +327,9 @@ static void univ8250_setup_timer(struct
|
|
uart_poll_timeout(port) + HZ / 5);
|
|
}
|
|
|
|
+ if (up->bugs & UART_BUG_NOMSI)
|
|
+ up->timer.function = serial8250_cts_poll_timeout;
|
|
+
|
|
/*
|
|
* If the "interrupt" for this port doesn't correspond with any
|
|
* hardware interrupt, we use a timer-based system. The original
|
|
--- a/drivers/tty/serial/8250/8250_port.c
|
|
+++ b/drivers/tty/serial/8250/8250_port.c
|
|
@@ -1529,6 +1529,9 @@ static void serial8250_stop_tx(struct ua
|
|
serial_icr_write(up, UART_ACR, up->acr);
|
|
}
|
|
serial8250_rpm_put(up);
|
|
+
|
|
+ if (port->hw_stopped && (up->bugs & UART_BUG_NOMSI))
|
|
+ mod_timer(&up->timer, jiffies + 1);
|
|
}
|
|
|
|
static inline void __start_tx(struct uart_port *port)
|
|
@@ -1642,6 +1645,9 @@ static void serial8250_start_tx(struct u
|
|
/* Port locked to synchronize UART_IER access against the console. */
|
|
lockdep_assert_held_once(&port->lock);
|
|
|
|
+ if (up->bugs & UART_BUG_NOMSI)
|
|
+ del_timer(&up->timer);
|
|
+
|
|
if (!port->x_char && uart_circ_empty(&port->state->xmit))
|
|
return;
|
|
|
|
@@ -1866,6 +1872,9 @@ unsigned int serial8250_modem_status(str
|
|
uart_handle_cts_change(port, status & UART_MSR_CTS);
|
|
|
|
wake_up_interruptible(&port->state->port.delta_msr_wait);
|
|
+ } else if (up->bugs & UART_BUG_NOMSI && port->hw_stopped &&
|
|
+ status & UART_MSR_CTS) {
|
|
+ uart_handle_cts_change(port, status & UART_MSR_CTS);
|
|
}
|
|
|
|
return status;
|