#include <linux/tty.h>
#include <linux/ratelimit.h>
#include <linux/tty_flip.h>
-#include <linux/serial_reg.h>
#include <linux/serial_core.h>
#include <linux/serial.h>
#include <linux/serial_8250.h>
.fifo_size = 16,
.tx_loadsz = 16,
.fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+ .rxtrig_bytes = {1, 4, 8, 14},
.flags = UART_CAP_FIFO,
},
[PORT_CIRRUS] = {
.tx_loadsz = 16,
.fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 |
UART_FCR_T_TRIG_00,
+ .rxtrig_bytes = {8, 16, 24, 28},
.flags = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
},
[PORT_16750] = {
.tx_loadsz = 64,
.fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 |
UART_FCR7_64BYTE,
+ .rxtrig_bytes = {1, 16, 32, 56},
.flags = UART_CAP_FIFO | UART_CAP_SLEEP | UART_CAP_AFE,
},
[PORT_STARTECH] = {
.tx_loadsz = 32,
.fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 |
UART_FCR_T_TRIG_10,
+ .rxtrig_bytes = {8, 16, 56, 60},
.flags = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
},
[PORT_16850] = {
.tx_loadsz = 8,
.fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 |
UART_FCR_T_TRIG_01,
+ .rxtrig_bytes = {1, 4, 8, 14},
.flags = UART_CAP_FIFO | UART_CAP_RTOIE,
},
[PORT_XR17D15X] = {
void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p)
{
- unsigned char fcr;
-
serial8250_clear_fifos(p);
- fcr = uart_config[p->port.type].fcr;
- serial_out(p, UART_FCR, fcr);
+ serial_out(p, UART_FCR, p->fcr);
}
EXPORT_SYMBOL_GPL(serial8250_clear_and_reinit_fifos);
struct ktermios *old)
{
struct uart_8250_port *up = up_to_u8250p(port);
- unsigned char cval, fcr = 0;
+ unsigned char cval;
unsigned long flags;
unsigned int baud, quot;
- int fifo_bug = 0;
switch (termios->c_cflag & CSIZE) {
case CS5:
if (termios->c_cflag & PARENB) {
cval |= UART_LCR_PARITY;
if (up->bugs & UART_BUG_PARITY)
- fifo_bug = 1;
+ up->fifo_bug = true;
}
if (!(termios->c_cflag & PARODD))
cval |= UART_LCR_EPAR;
quot++;
if (up->capabilities & UART_CAP_FIFO && port->fifosize > 1) {
- fcr = uart_config[port->type].fcr;
- if ((baud < 2400 && !up->dma) || fifo_bug) {
- fcr &= ~UART_FCR_TRIGGER_MASK;
- fcr |= UART_FCR_TRIGGER_1;
+ /* NOTE: If fifo_bug is not set, a user can set RX_trigger. */
+ if ((baud < 2400 && !up->dma) || up->fifo_bug) {
+ up->fcr &= ~UART_FCR_TRIGGER_MASK;
+ up->fcr |= UART_FCR_TRIGGER_1;
}
}
* is written without DLAB set, this mode will be disabled.
*/
if (port->type == PORT_16750)
- serial_port_out(port, UART_FCR, fcr);
+ serial_port_out(port, UART_FCR, up->fcr);
serial_port_out(port, UART_LCR, cval); /* reset DLAB */
up->lcr = cval; /* Save LCR */
if (port->type != PORT_16750) {
/* emulated UARTs (Lucent Venus 167x) need two steps */
- if (fcr & UART_FCR_ENABLE_FIFO)
+ if (up->fcr & UART_FCR_ENABLE_FIFO)
serial_port_out(port, UART_FCR, UART_FCR_ENABLE_FIFO);
- serial_port_out(port, UART_FCR, fcr); /* set fcr */
+ serial_port_out(port, UART_FCR, up->fcr); /* set fcr */
}
serial8250_set_mctrl(port, port->mctrl);
spin_unlock_irqrestore(&port->lock, flags);
return ret;
}
+static int fcr_get_rxtrig_bytes(struct uart_8250_port *up)
+{
+ const struct serial8250_config *conf_type = &uart_config[up->port.type];
+ unsigned char bytes;
+
+ bytes = conf_type->rxtrig_bytes[UART_FCR_R_TRIG_BITS(up->fcr)];
+
+ return bytes ? bytes : -EOPNOTSUPP;
+}
+
+static int bytes_to_fcr_rxtrig(struct uart_8250_port *up, unsigned char bytes)
+{
+ const struct serial8250_config *conf_type = &uart_config[up->port.type];
+ int i;
+
+ if (!conf_type->rxtrig_bytes[UART_FCR_R_TRIG_BITS(UART_FCR_R_TRIG_00)])
+ return -EOPNOTSUPP;
+
+ for (i = 1; i < UART_FCR_R_TRIG_MAX_STATE; i++) {
+ if (bytes < conf_type->rxtrig_bytes[i])
+ /* Use the nearest lower value */
+ return (--i) << UART_FCR_R_TRIG_SHIFT;
+ }
+
+ return UART_FCR_R_TRIG_11;
+}
+
+static int do_get_rxtrig(struct tty_port *port)
+{
+ struct uart_state *state = container_of(port, struct uart_state, port);
+ struct uart_port *uport = state->uart_port;
+ struct uart_8250_port *up =
+ container_of(uport, struct uart_8250_port, port);
+
+ if (!(up->capabilities & UART_CAP_FIFO) || uport->fifosize <= 1)
+ return -EINVAL;
+
+ return fcr_get_rxtrig_bytes(up);
+}
+
+static int do_serial8250_get_rxtrig(struct tty_port *port)
+{
+ int rxtrig_bytes;
+
+ mutex_lock(&port->mutex);
+ rxtrig_bytes = do_get_rxtrig(port);
+ mutex_unlock(&port->mutex);
+
+ return rxtrig_bytes;
+}
+
+static ssize_t serial8250_get_attr_rx_trig_bytes(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct tty_port *port = dev_get_drvdata(dev);
+ int rxtrig_bytes;
+
+ rxtrig_bytes = do_serial8250_get_rxtrig(port);
+ if (rxtrig_bytes < 0)
+ return rxtrig_bytes;
+
+ return snprintf(buf, PAGE_SIZE, "%d\n", rxtrig_bytes);
+}
+
+static int do_set_rxtrig(struct tty_port *port, unsigned char bytes)
+{
+ struct uart_state *state = container_of(port, struct uart_state, port);
+ struct uart_port *uport = state->uart_port;
+ struct uart_8250_port *up =
+ container_of(uport, struct uart_8250_port, port);
+ int rxtrig;
+
+ if (!(up->capabilities & UART_CAP_FIFO) || uport->fifosize <= 1 ||
+ up->fifo_bug)
+ return -EINVAL;
+
+ rxtrig = bytes_to_fcr_rxtrig(up, bytes);
+ if (rxtrig < 0)
+ return rxtrig;
+
+ serial8250_clear_fifos(up);
+ up->fcr &= ~UART_FCR_TRIGGER_MASK;
+ up->fcr |= (unsigned char)rxtrig;
+ serial_out(up, UART_FCR, up->fcr);
+ return 0;
+}
+
+static int do_serial8250_set_rxtrig(struct tty_port *port, unsigned char bytes)
+{
+ int ret;
+
+ mutex_lock(&port->mutex);
+ ret = do_set_rxtrig(port, bytes);
+ mutex_unlock(&port->mutex);
+
+ return ret;
+}
+
+static ssize_t serial8250_set_attr_rx_trig_bytes(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct tty_port *port = dev_get_drvdata(dev);
+ unsigned char bytes;
+ int ret;
+
+ if (!count)
+ return -EINVAL;
+
+ ret = kstrtou8(buf, 10, &bytes);
+ if (ret < 0)
+ return ret;
+
+ ret = do_serial8250_set_rxtrig(port, bytes);
+ if (ret < 0)
+ return ret;
+
+ return count;
+}
+
+static DEVICE_ATTR(rx_trig_bytes, S_IRUSR | S_IWUSR | S_IRGRP,
+ serial8250_get_attr_rx_trig_bytes,
+ serial8250_set_attr_rx_trig_bytes);
+
+static struct attribute *serial8250_dev_attrs[] = {
+ &dev_attr_rx_trig_bytes.attr,
+ NULL,
+ };
+
+static struct attribute_group serial8250_dev_attr_group = {
+ .attrs = serial8250_dev_attrs,
+ };
+
+static void register_dev_spec_attr_grp(struct uart_8250_port *up)
+{
+ const struct serial8250_config *conf_type = &uart_config[up->port.type];
+
+ if (conf_type->rxtrig_bytes[0])
+ up->port.attr_group = &serial8250_dev_attr_group;
+}
+
static void serial8250_config_port(struct uart_port *port, int flags)
{
struct uart_8250_port *up = up_to_u8250p(port);
if ((port->type == PORT_XR17V35X) ||
(port->type == PORT_XR17D15X))
port->handle_irq = exar_handle_irq;
+
+ register_dev_spec_attr_grp(up);
+ up->fcr = uart_config[up->port.type].fcr;
}
static int
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