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  1. 10 Feb, 2017 8 commits
  3. 09 Feb, 2017 2 commits
  5. 06 Feb, 2017 14 commits
  7. 03 Feb, 2017 13 commits
  9. 31 Jan, 2017 2 commits
    • Fabio Estevam's avatar
      serial: imx: Fix the CTS_B polarity in RS485 mode · bc2be239
      Fabio Estevam authored 
      When userspace passes the SER_RS485_RTS_ON_SEND flag it means that the
CTS_B pin should go to logic level high before the transmission begins.

CTS_B goes to logic level high when both CTSC and CTS bits are cleared.

When userspace passes the SER_RS485_RTS_AFTER_SEND flag it means that the
CTS_B pin should go to logic level low after the transmission finishes.

CTS_B goes to logic level low when CTSC bit is cleared and CTS bit is set.

So fix the CTS_B polarity logic.
Signed-off-by: default avatarFabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      bc2be239
    • Fabio Estevam's avatar
      serial: imx: Fix the RTS GPIO polarity in RS485 mode · 1a613626
      Fabio Estevam authored 
      On a board that needs to drive RTS GPIO high in order to enable the
transmission of a RS485 transceiver the following description is
passed in the devide tree:

&uart4 {
        pinctrl-names = "default";
        pinctrl-0 = <&pinctrl_uart4>;
        rts-gpios = <&gpio6 2 GPIO_ACTIVE_HIGH>;
        status = "okay";
};

and userspace configures the uart port as follows:

/* enable RS485 mode: */
rs485conf.flags |= SER_RS485_ENABLED;

/* set logical level for RTS pin equal to 1 when sending: */
rs485conf.flags |= SER_RS485_RTS_ON_SEND;

/* set logical level for RTS pin equal to 0 after sending: */
rs485conf.flags &= ~(SER_RS485_RTS_AFTER_SEND);

However the RTS GPIO polarity observed in the oscilloscope is inverted.

When the SER_RS485_RTS_ON_SEND flag is set the imx_port_rts_active()
function should be called and following the same logic when
SER_RS485_RTS_AFTER_SEND flag is cleared the imx_port_rts_inactive()
should be called.

Do such logic change so that RS485 communication in half duplex can
work successfully when the RTS GPIO pin is passed via device tree.
Signed-off-by: default avatarFabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      1a613626
  11. 27 Jan, 2017 1 commit
    • Arnd Bergmann's avatar
      8250: of: remove remnants of generic of_serial driver · aa42db44
      Arnd Bergmann authored 
      During build testing, I ran into a warning in a driver that I
had written myself at some point:

drivers/tty/serial/8250/8250_of.c: In function 'of_platform_serial_probe':
drivers/tty/serial/8250/8250_of.c:233:1: error: the frame size of 1200 bytes is larger than 1152 bytes [-Werror=frame-larger-than=]

This is harmless by itself, but it shows two other problems in
the driver:

- It still tries to be generic enough to handle all kinds of serial
  ports, where in reality the driver has been 8250-only for a while,
  and every other uart has its own DT support

- As a result of that generalization, we keep two copies of
  'struct uart_port' on the stack during probe(). This is completely
  unnessary.

Removing the last code dealing with unsupported port_type values
solves both problems nicely, and reduces the stack size.
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      aa42db44
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