tegra, serial8250: add ->handle_break() uart_port op
The "KT" serial port has another use case for a "received break" quirk,
so before adding another special case to the 8250 core take this
opportunity to push such quirks out of the core and into a uart_port op.
Stephen says:
"If the callback function is to no longer live in 8250.c itself,
arch/arm/mach-tegra/devices.c isn't logically a good place to put it,
and that file will be going away once we get rid of all the board files
and move solely to device tree."
...so since 8250_pci.c houses all the quirks for pci serial devices this
quirk is similarly housed in of_serial.c. Once the open firmware
conversion completes the infrastructure details
(include/linux/of_serial.h, and the export) can all be removed to make
this self contained to of_serial.c.
Cc: Nhan H Mai <nhan.h.mai@intel.com>
Cc: Colin Cross <ccross@android.com>
Cc: Olof Johansson <olof@lixom.net>
[stephen: kill CONFIG_SERIAL_TEGRA in favor just using CONFIG_ARCH_TEGRA]
Cc: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Sudhakar Mamillapalli <sudhakar@fb.com>
Reported-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/8250/8250.c b/drivers/tty/serial/8250/8250.c
index 5b149b4..dffd623 100644
--- a/drivers/tty/serial/8250/8250.c
+++ b/drivers/tty/serial/8250/8250.c
@@ -1332,27 +1332,6 @@
}
/*
- * Clear the Tegra rx fifo after a break
- *
- * FIXME: This needs to become a port specific callback once we have a
- * framework for this
- */
-static void clear_rx_fifo(struct uart_8250_port *up)
-{
- unsigned int status, tmout = 10000;
- do {
- status = serial_in(up, UART_LSR);
- if (status & (UART_LSR_FIFOE | UART_LSR_BRK_ERROR_BITS))
- status = serial_in(up, UART_RX);
- else
- break;
- if (--tmout == 0)
- break;
- udelay(1);
- } while (1);
-}
-
-/*
* serial8250_rx_chars: processes according to the passed in LSR
* value, and returns the remaining LSR bits not handled
* by this Rx routine.
@@ -1386,20 +1365,10 @@
up->lsr_saved_flags = 0;
if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) {
- /*
- * For statistics only
- */
if (lsr & UART_LSR_BI) {
lsr &= ~(UART_LSR_FE | UART_LSR_PE);
port->icount.brk++;
/*
- * If tegra port then clear the rx fifo to
- * accept another break/character.
- */
- if (port->type == PORT_TEGRA)
- clear_rx_fifo(up);
-
- /*
* We do the SysRQ and SAK checking
* here because otherwise the break
* may get masked by ignore_status_mask
@@ -3037,6 +3006,7 @@
port.serial_in = p->serial_in;
port.serial_out = p->serial_out;
port.handle_irq = p->handle_irq;
+ port.handle_break = p->handle_break;
port.set_termios = p->set_termios;
port.pm = p->pm;
port.dev = &dev->dev;
@@ -3209,6 +3179,8 @@
uart->port.set_termios = port->set_termios;
if (port->pm)
uart->port.pm = port->pm;
+ if (port->handle_break)
+ uart->port.handle_break = port->handle_break;
if (serial8250_isa_config != NULL)
serial8250_isa_config(0, &uart->port,
diff --git a/drivers/tty/serial/of_serial.c b/drivers/tty/serial/of_serial.c
index e8c9cee..5410c06 100644
--- a/drivers/tty/serial/of_serial.c
+++ b/drivers/tty/serial/of_serial.c
@@ -12,10 +12,13 @@
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
+#include <linux/delay.h>
#include <linux/serial_core.h>
#include <linux/serial_8250.h>
+#include <linux/serial_reg.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
+#include <linux/of_serial.h>
#include <linux/of_platform.h>
#include <linux/nwpserial.h>
@@ -24,6 +27,26 @@
int line;
};
+#ifdef CONFIG_ARCH_TEGRA
+void tegra_serial_handle_break(struct uart_port *p)
+{
+ unsigned int status, tmout = 10000;
+
+ do {
+ status = p->serial_in(p, UART_LSR);
+ if (status & (UART_LSR_FIFOE | UART_LSR_BRK_ERROR_BITS))
+ status = p->serial_in(p, UART_RX);
+ else
+ break;
+ if (--tmout == 0)
+ break;
+ udelay(1);
+ } while (1);
+}
+/* FIXME remove this export when tegra finishes conversion to open firmware */
+EXPORT_SYMBOL_GPL(tegra_serial_handle_break);
+#endif
+
/*
* Fill a struct uart_port for a given device node
*/
@@ -84,6 +107,9 @@
| UPF_FIXED_PORT | UPF_FIXED_TYPE;
port->dev = &ofdev->dev;
+ if (type == PORT_TEGRA)
+ port->handle_break = tegra_serial_handle_break;
+
return 0;
}