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authorLinus Torvalds <torvalds@linux-foundation.org>2011-03-16 15:11:04 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-03-16 15:11:04 -0700
commite6bee325e49f17c65c1fd66e9e8b348c85788341 (patch)
treebcc9e5d8e82efa9009edd481a837cc3626360091 /drivers/tty/serial/8250.c
parenta5e6b135bdff649e4330f98e2e80dbb1984f7e77 (diff)
parent6ae705b23be8da52d3163be9d81e9b767876aaf9 (diff)
Merge branch 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6
* 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (76 commits) pch_uart: reference clock on CM-iTC pch_phub: add new device ML7213 n_gsm: fix UIH control byte : P bit should be 0 n_gsm: add a documentation serial: msm_serial_hs: Add MSM high speed UART driver tty_audit: fix tty_audit_add_data live lock on audit disabled tty: move cd1865.h to drivers/staging/tty/ Staging: tty: fix build with epca.c driver pcmcia: synclink_cs: fix prototype for mgslpc_ioctl() Staging: generic_serial: fix double locking bug nozomi: don't use flush_scheduled_work() tty/serial: Relax the device_type restriction from of_serial MAINTAINERS: Update HVC file patterns tty: phase out of ioctl file pointer for tty3270 as well tty: forgot to remove ipwireless from drivers/char/pcmcia/Makefile pch_uart: Fix DMA channel miss-setting issue. pch_uart: fix exclusive access issue pch_uart: fix auto flow control miss-setting issue pch_uart: fix uart clock setting issue pch_uart : Use dev_xxx not pr_xxx ... Fix up trivial conflicts in drivers/misc/pch_phub.c (same patch applied twice, then changes to the same area in one branch)
Diffstat (limited to 'drivers/tty/serial/8250.c')
-rw-r--r--drivers/tty/serial/8250.c33
1 files changed, 21 insertions, 12 deletions
diff --git a/drivers/tty/serial/8250.c b/drivers/tty/serial/8250.c
index 3975df6f7fd..b3b881bc471 100644
--- a/drivers/tty/serial/8250.c
+++ b/drivers/tty/serial/8250.c
@@ -954,6 +954,23 @@ static int broken_efr(struct uart_8250_port *up)
return 0;
}
+static inline int ns16550a_goto_highspeed(struct uart_8250_port *up)
+{
+ unsigned char status;
+
+ status = serial_in(up, 0x04); /* EXCR2 */
+#define PRESL(x) ((x) & 0x30)
+ if (PRESL(status) == 0x10) {
+ /* already in high speed mode */
+ return 0;
+ } else {
+ status &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */
+ status |= 0x10; /* 1.625 divisor for baud_base --> 921600 */
+ serial_outp(up, 0x04, status);
+ }
+ return 1;
+}
+
/*
* We know that the chip has FIFOs. Does it have an EFR? The
* EFR is located in the same register position as the IIR and
@@ -1025,12 +1042,8 @@ static void autoconfig_16550a(struct uart_8250_port *up)
quot = serial_dl_read(up);
quot <<= 3;
- status1 = serial_in(up, 0x04); /* EXCR2 */
- status1 &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */
- status1 |= 0x10; /* 1.625 divisor for baud_base --> 921600 */
- serial_outp(up, 0x04, status1);
-
- serial_dl_write(up, quot);
+ if (ns16550a_goto_highspeed(up))
+ serial_dl_write(up, quot);
serial_outp(up, UART_LCR, 0);
@@ -3025,17 +3038,13 @@ void serial8250_resume_port(int line)
struct uart_8250_port *up = &serial8250_ports[line];
if (up->capabilities & UART_NATSEMI) {
- unsigned char tmp;
-
/* Ensure it's still in high speed mode */
serial_outp(up, UART_LCR, 0xE0);
- tmp = serial_in(up, 0x04); /* EXCR2 */
- tmp &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */
- tmp |= 0x10; /* 1.625 divisor for baud_base --> 921600 */
- serial_outp(up, 0x04, tmp);
+ ns16550a_goto_highspeed(up);
serial_outp(up, UART_LCR, 0);
+ up->port.uartclk = 921600*16;
}
uart_resume_port(&serial8250_reg, &up->port);
}