leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

serial: tegra: protect IER against LCR.DLAB

Browse Source 
The IER and DLH registers occupy the same address space, selected by
the LCR.DLAB bit. Hence, add port lock to protect IER when LCR.DLAB bit
is set.

Signed-off-by: Ahung Cheng <ahcheng@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/1565609303-27000-5-git-send-email-kyarlagadda@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ahung Cheng 2019-08-12 16:58:13 +05:30 committed by Greg Kroah-Hartman
parent 6300b140c2
commit 18a4c404d2
1 changed files with 3 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
drivers/tty/serial/serial-tegra.c
View File

@ -294,6 +294,7 @@ static int tegra_set_baudrate(struct tegra_uart_port *tup, unsigned int baud)
unsigned long rate;
unsigned int divisor;
unsigned long lcr;
unsigned long flags;
int ret;
if (tup->current_baud == baud)
@ -313,6 +314,7 @@ static int tegra_set_baudrate(struct tegra_uart_port *tup, unsigned int baud)
divisor = DIV_ROUND_CLOSEST(rate, baud * 16);
}
spin_lock_irqsave(&tup->uport.lock, flags);
lcr = tup->lcr_shadow;
lcr |= UART_LCR_DLAB;
tegra_uart_write(tup, lcr, UART_LCR);
@ -325,6 +327,7 @@ static int tegra_set_baudrate(struct tegra_uart_port *tup, unsigned int baud)
/* Dummy read to ensure the write is posted */
tegra_uart_read(tup, UART_SCR);
spin_unlock_irqrestore(&tup->uport.lock, flags);
tup->current_baud = baud;