p71924506
/
linux_old1
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

serial: sh-sci: Correct pin initialization on (H)SCIF 

Correct pin initialization on (H)SCIF:
  - RTS must be deasserted (it's active low),
  - SCK must be an input, as it may be used as the optional external
    clock input.

Initial pin configuration must always be done:
  - Regardless of the presence of dedicated RTS and CTS pins: if the
    register exists, the RTS/CTS bits exist, too,
  - Regardless of hardware flow control being enabled or not: RTS must
    be deasserted.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Geert Uytterhoeven 2016-06-03 12:00:08 +02:00 committed by Greg Kroah-Hartman
parent 4780c09f7a
commit d2b9775d79
1 changed files with 7 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
drivers/tty/serial/sh-sci.c
View File

@ -712,21 +712,14 @@ static void sci_init_pins(struct uart_port *port, unsigned int cflag)
return; return;
} }
/* if (sci_getreg(port, SCSPTR)->size) {
* For the generic path SCSPTR is necessary. Bail out if that's u16 status = serial_port_in(port, SCSPTR);
* unavailable, too.
*/
if (!sci_getreg(port, SCSPTR)->size)
return;
if ((s->cfg->capabilities & SCIx_HAVE_RTSCTS) && /* RTS# is output, driven 1 */
((!(cflag & CRTSCTS)))) { status |= SCSPTR_RTSIO | SCSPTR_RTSDT;
unsigned short status; /* CTS# and SCK are inputs */
status &= ~(SCSPTR_CTSIO | SCSPTR_SCKIO);
status = serial_port_in(port, SCSPTR); serial_port_out(port, SCSPTR, status);
status &= ~SCSPTR_CTSIO;
status |= SCSPTR_RTSIO;
serial_port_out(port, SCSPTR, status); /* Set RTS = 1 */
} }
} }