UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

serial: sprd: clear timeout interrupt only rather than all interrupts 

On Spreadtrum's serial device, nearly all of interrupts would be cleared
by hardware except timeout interrupt.  This patch removed the operation
of clearing all interrupt in irq handler, instead added an if statement
to check if the timeout interrupt is supposed to be cleared.

Wrongly clearing timeout interrupt would lead to uart data stay in rx
fifo, that means the driver cannot read them out anymore.

Signed-off-by: Lanqing Liu <lanqing.liu@spreadtrum.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Lanqing Liu 2017-07-18 17:58:13 +08:00 committed by Greg Kroah-Hartman
parent 64432a8551
commit 4350782570
1 changed files with 3 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/tty/serial/sprd_serial.c
View File

@ -63,6 +63,7 @@
/* interrupt clear register */
#define SPRD_ICLR 0x0014
#define SPRD_ICLR_TIMEOUT BIT(13)
/* line control register */
#define SPRD_LCR 0x0018
@ -298,7 +299,8 @@ static irqreturn_t sprd_handle_irq(int irq, void *dev_id)
return IRQ_NONE;
}
serial_out(port, SPRD_ICLR, ~0);
if (ims & SPRD_IMSR_TIMEOUT)
serial_out(port, SPRD_ICLR, SPRD_ICLR_TIMEOUT);
if (ims & (SPRD_IMSR_RX_FIFO_FULL |
SPRD_IMSR_BREAK_DETECT | SPRD_IMSR_TIMEOUT))