[PATCH V5 4/8] USB: f81232: implement set_termios

From: Peter Hung
Date: Fri Feb 06 2015 - 04:48:50 EST


The original driver had do not any h/w change in driver.
This patch implements with configure H/W for
baud/parity/word length/stop bits functional.

Some init step extract to f81232_port_init(), called once with open().
And refine baudrate setting to f81232_set_baudrate()

Signed-off-by: Peter Hung <hpeter+linux_kernel@xxxxxxxxx>
---
drivers/usb/serial/f81232.c | 145 +++++++++++++++++++++++++++++++++++++++++---
1 file changed, 138 insertions(+), 7 deletions(-)

diff --git a/drivers/usb/serial/f81232.c b/drivers/usb/serial/f81232.c
index 9ea498a..06d1eb0 100644
--- a/drivers/usb/serial/f81232.c
+++ b/drivers/usb/serial/f81232.c
@@ -31,11 +31,19 @@ static const struct usb_device_id id_table[] = {
};
MODULE_DEVICE_TABLE(usb, id_table);

+/* Maximum baudrate for F81232 */
+#define F81232_MAX_BAUDRATE 115200L
+
/* USB Control EP parameter */
#define F81232_REGISTER_REQUEST 0xA0
#define F81232_GET_REGISTER 0xc0
+#define F81232_SET_REGISTER 0x40

#define SERIAL_BASE_ADDRESS 0x0120
+#define RECEIVE_BUFFER_REGISTER (0x00 + SERIAL_BASE_ADDRESS)
+#define INTERRUPT_ENABLE_REGISTER (0x01 + SERIAL_BASE_ADDRESS)
+#define FIFO_CONTROL_REGISTER (0x02 + SERIAL_BASE_ADDRESS)
+#define LINE_CONTROL_REGISTER (0x03 + SERIAL_BASE_ADDRESS)
#define MODEM_STATUS_REGISTER (0x06 + SERIAL_BASE_ADDRESS)

#define CONTROL_DTR 0x01
@@ -61,6 +69,14 @@ struct f81232_private {
struct usb_serial_port *port;
};

+static int calc_baud_divisor(u32 baudrate)
+{
+ if (!baudrate)
+ return 0;
+ else
+ return DIV_ROUND_CLOSEST(F81232_MAX_BAUDRATE, baudrate);
+}
+
static int f81232_get_register(struct usb_serial_port *port,
u16 reg, u8 *data)
{
@@ -82,6 +98,27 @@ static int f81232_get_register(struct usb_serial_port *port,
return status;
}

+static int f81232_set_register(struct usb_serial_port *port,
+ u16 reg, u8 data)
+{
+ int status;
+ struct usb_device *dev = port->serial->dev;
+
+ status = usb_control_msg(dev,
+ usb_sndctrlpipe(dev, 0),
+ F81232_REGISTER_REQUEST,
+ F81232_SET_REGISTER,
+ reg,
+ 0,
+ &data,
+ sizeof(data),
+ USB_CTRL_SET_TIMEOUT);
+ if (status < 0)
+ dev_err(&port->dev, "%s status: %d\n", __func__, status);
+
+ return status;
+}
+
static void f81232_read_msr(struct usb_serial_port *port)
{
int status;
@@ -247,18 +284,106 @@ static void f81232_break_ctl(struct tty_struct *tty, int break_state)
*/
}

+static void f81232_set_baudrate(struct usb_serial_port *port, int baudrate)
+{
+ u8 divisor;
+ int status = 0;
+
+ divisor = calc_baud_divisor(baudrate);
+
+ status = f81232_set_register(port, LINE_CONTROL_REGISTER,
+ UART_LCR_DLAB); /* DLAB */
+ if (status < 0) {
+ dev_err(&port->dev, "%s status: %d line:%d\n",
+ __func__, status, __LINE__);
+ }
+
+ status = f81232_set_register(port, RECEIVE_BUFFER_REGISTER,
+ divisor & 0x00ff); /* low */
+ if (status < 0) {
+ dev_err(&port->dev, "%s status: %d line:%d\n",
+ __func__, status, __LINE__);
+ }
+
+ status = f81232_set_register(port, INTERRUPT_ENABLE_REGISTER,
+ (divisor & 0xff00) >> 8); /* high */
+ if (status < 0) {
+ dev_err(&port->dev, "%s status: %d line:%d\n", __func__,
+ status, __LINE__);
+ }
+
+ status = f81232_set_register(port, LINE_CONTROL_REGISTER, 0x00);
+ if (status < 0) {
+ dev_err(&port->dev, "%s status: %d line:%d\n", __func__,
+ status, __LINE__);
+ }
+}
+
+static int f81232_port_init(struct usb_serial_port *port)
+{
+ u8 data;
+ int status = 0;
+
+ /* fifo on, trigger8, clear TX/RX*/
+ data = UART_FCR_TRIGGER_8 | UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR
+ | UART_FCR_CLEAR_XMIT;
+
+ status |= f81232_set_register(port, FIFO_CONTROL_REGISTER, data);
+
+ /* MSR Interrupt only, LSR will read from Bulk-in odd byte */
+ data = UART_IER_MSI;
+
+ /* IER */
+ status |= f81232_set_register(port, INTERRUPT_ENABLE_REGISTER, data);
+ if (status < 0) {
+ dev_err(&port->dev, "%s set error: %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)
{
- /* FIXME - Stubbed out for now */
+ u8 new_lcr = 0;
+ int status = 0;

- /* Don't change anything if nothing has changed */
- if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios))
- return;
+ f81232_set_baudrate(port, tty_get_baud_rate(tty));
+
+ if (C_PARENB(tty)) {
+ new_lcr |= UART_LCR_PARITY;
+
+ if (!C_PARODD(tty))
+ new_lcr |= UART_LCR_EPAR;
+
+ if (C_CMSPAR(tty))
+ new_lcr |= UART_LCR_SPAR;
+ }
+
+ if (C_CSTOPB(tty))
+ new_lcr |= UART_LCR_STOP;
+
+ switch (C_CSIZE(tty)) {
+ case CS5:
+ new_lcr |= UART_LCR_WLEN5;
+ break;
+ case CS6:
+ new_lcr |= UART_LCR_WLEN6;
+ break;
+ case CS7:
+ new_lcr |= UART_LCR_WLEN7;
+ break;
+ default:
+ case CS8:
+ new_lcr |= UART_LCR_WLEN8;
+ break;
+ }
+
+ status = f81232_set_register(port, LINE_CONTROL_REGISTER, new_lcr);
+ if (status < 0)
+ dev_err(&port->dev, "%s set error: %d\n", __func__, status);

- /* Do the real work here... */
- if (old_termios)
- tty_termios_copy_hw(&tty->termios, old_termios);
}

static int f81232_tiocmget(struct tty_struct *tty)
@@ -278,6 +403,12 @@ static int f81232_open(struct tty_struct *tty, struct usb_serial_port *port)
{
int result;

+ result = f81232_port_init(port);
+ if (result) {
+ dev_err(&port->dev, "%s - init fail: %d\n", __func__, result);
+ return result;
+ }
+
/* Setup termios */
if (tty)
f81232_set_termios(tty, port, NULL);
--
1.9.1

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