Re: [PATCH V7 07/11] USB: f81232: implement port_enable function

Johan Hovold
2015-02-25T20:44:58Z

On Tue, Feb 24, 2015 at 06:16:22PM +0800, Peter Hung wrote:
> We put FCR/IER initial step to f81232_port_enable(). When port is open,
> it set MSR interrupt on. Otherwise set it off.
>
> Signed-off-by: Peter Hung <hpeter+linux_kernel@gmail.com>
> ---
> drivers/usb/serial/f81232.c | 39 +++++++++++++++++++++++++++++++++++++++
> 1 file changed, 39 insertions(+)
>
> diff --git a/drivers/usb/serial/f81232.c b/drivers/usb/serial/f81232.c
> index 21f606f..f5c9060 100644
> --- a/drivers/usb/serial/f81232.c
> +++ b/drivers/usb/serial/f81232.c
> @@ -37,6 +37,8 @@ MODULE_DEVICE_TABLE(usb, id_table);
> #define F81232_SET_REGISTER 0x40
>
> #define SERIAL_BASE_ADDRESS 0x0120
> +#define INTERRUPT_ENABLE_REGISTER (0x01 + SERIAL_BASE_ADDRESS)
> +#define FIFO_CONTROL_REGISTER (0x02 + SERIAL_BASE_ADDRESS)
> #define MODEM_CONTROL_REGISTER (0x04 + SERIAL_BASE_ADDRESS)
> #define MODEM_STATUS_REGISTER (0x06 + SERIAL_BASE_ADDRESS)
>
> @@ -367,6 +369,33 @@ static void f81232_break_ctl(struct tty_struct *tty, int break_state)
> */
> }
>
> +static int f81232_port_enable(struct usb_serial_port *port, int enable)

Split this in two functions, enable and disable, since you don't need to
set FCR on close.

> +{
> + u8 data = 0;
> + int status;
> +
> + /* fifo on, trigger8, clear TX/RX*/
> + data = UART_FCR_TRIGGER_8 | UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR
> + | UART_FCR_CLEAR_XMIT;

Put the final | before the line break.

> +
> + status = f81232_set_register(port, FIFO_CONTROL_REGISTER, data);
> + if (status) {
> + dev_err(&port->dev, "%s failed to set FCR: %d\n", __func__, status);
> + return status;
> + }
> +
> + /* MSR Interrupt only, LSR will read from Bulk-in odd byte */
> + data = enable ? UART_IER_MSI : 0;
> +
> + status = f81232_set_register(port, INTERRUPT_ENABLE_REGISTER, data);
> + if (status) {
> + dev_err(&port->dev, "%s failed to set IER: %d\n", __func__, status);
> + return status;
> + }
> +
> + return 0;
> +}
> +
> static void f81232_set_termios(struct tty_struct *tty,
> struct usb_serial_port *port, struct ktermios *old_termios)
> {
> @@ -418,6 +447,12 @@ static int f81232_open(struct tty_struct *tty, struct usb_serial_port *port)
> {
> int result;
>
> + result = f81232_port_enable(port, 1);
> + if (result) {
> + dev_err(&port->dev, "%s - init fail: %d\n", __func__, result);
> + return result;

You already log the error in port_enable.

> + }
> +
> /* Setup termios */
> if (tty)
> f81232_set_termios(tty, port, NULL);
> @@ -440,6 +475,10 @@ static int f81232_open(struct tty_struct *tty, struct usb_serial_port *port)
>
> static void f81232_close(struct usb_serial_port *port)
> {
> + int result = f81232_port_enable(port, 0);

Separate the declaration from the function call.

> + if (result)
> + dev_err(&port->dev, "%s - init fail: %d\n", __func__, result);
> +

Already logged as well.

> usb_serial_generic_close(port);
> usb_kill_urb(port->interrupt_in_urb);
> }

Johan