diff options
Diffstat (limited to 'drivers/tty/serial/8250/8250_core.c')
| -rw-r--r-- | drivers/tty/serial/8250/8250_core.c | 230 |
1 files changed, 177 insertions, 53 deletions
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index 7a91c6d1eb7d..1d42dba6121d 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -31,7 +31,6 @@ #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> @@ -161,6 +160,7 @@ static const struct serial8250_config uart_config[] = { .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] = { @@ -180,6 +180,7 @@ static const struct serial8250_config uart_config[] = { .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] = { @@ -188,6 +189,7 @@ static const struct serial8250_config uart_config[] = { .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] = { @@ -209,6 +211,7 @@ static const struct serial8250_config uart_config[] = { .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] = { @@ -266,6 +269,7 @@ static const struct serial8250_config uart_config[] = { .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] = { @@ -439,8 +443,7 @@ static int exar_handle_irq(struct uart_port *port); static void set_io_from_upio(struct uart_port *p) { - struct uart_8250_port *up = - container_of(p, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(p); up->dl_read = default_serial_dl_read; up->dl_write = default_serial_dl_write; @@ -531,11 +534,8 @@ static void serial8250_clear_fifos(struct uart_8250_port *p) 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); @@ -1277,8 +1277,7 @@ static inline void __stop_tx(struct uart_8250_port *p) static void serial8250_stop_tx(struct uart_port *port) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); __stop_tx(up); @@ -1293,8 +1292,7 @@ static void serial8250_stop_tx(struct uart_port *port) static void serial8250_start_tx(struct uart_port *port) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); if (up->dma && !serial8250_tx_dma(up)) { return; @@ -1322,8 +1320,7 @@ static void serial8250_start_tx(struct uart_port *port) static void serial8250_stop_rx(struct uart_port *port) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); up->ier &= ~UART_IER_RLSI; up->port.read_status_mask &= ~UART_LSR_DR; @@ -1332,8 +1329,7 @@ static void serial8250_stop_rx(struct uart_port *port) static void serial8250_enable_ms(struct uart_port *port) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); /* no MSR capabilities */ if (up->bugs & UART_BUG_NOMSR) @@ -1499,8 +1495,7 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir) { unsigned char status; unsigned long flags; - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); int dma_err = 0; if (iir & UART_IIR_NO_INT) @@ -1785,8 +1780,7 @@ static void serial8250_backup_timeout(unsigned long data) static unsigned int serial8250_tx_empty(struct uart_port *port) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); unsigned long flags; unsigned int lsr; @@ -1800,8 +1794,7 @@ static unsigned int serial8250_tx_empty(struct uart_port *port) static unsigned int serial8250_get_mctrl(struct uart_port *port) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); unsigned int status; unsigned int ret; @@ -1821,8 +1814,7 @@ static unsigned int serial8250_get_mctrl(struct uart_port *port) static void serial8250_set_mctrl(struct uart_port *port, unsigned int mctrl) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); unsigned char mcr = 0; if (mctrl & TIOCM_RTS) @@ -1843,8 +1835,7 @@ static void serial8250_set_mctrl(struct uart_port *port, unsigned int mctrl) static void serial8250_break_ctl(struct uart_port *port, int break_state) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); unsigned long flags; spin_lock_irqsave(&port->lock, flags); @@ -1911,8 +1902,7 @@ static void serial8250_put_poll_char(struct uart_port *port, unsigned char c) { unsigned int ier; - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); /* * First save the IER then disable the interrupts @@ -1941,8 +1931,7 @@ static void serial8250_put_poll_char(struct uart_port *port, static int serial8250_startup(struct uart_port *port) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); unsigned long flags; unsigned char lsr, iir; int retval; @@ -2194,8 +2183,7 @@ dont_test_tx_en: static void serial8250_shutdown(struct uart_port *port) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); unsigned long flags; /* @@ -2268,12 +2256,10 @@ void serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, struct ktermios *old) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); - unsigned char cval, fcr = 0; + struct uart_8250_port *up = up_to_u8250p(port); + unsigned char cval; unsigned long flags; unsigned int baud, quot; - int fifo_bug = 0; switch (termios->c_cflag & CSIZE) { case CS5: @@ -2296,7 +2282,7 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, 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; @@ -2320,10 +2306,10 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, 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; } } @@ -2456,15 +2442,15 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, * 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); @@ -2498,8 +2484,7 @@ serial8250_set_ldisc(struct uart_port *port, int new) void serial8250_do_pm(struct uart_port *port, unsigned int state, unsigned int oldstate) { - struct uart_8250_port *p = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *p = up_to_u8250p(port); serial8250_set_sleep(p, state != 0); } @@ -2630,8 +2615,7 @@ static void serial8250_release_rsa_resource(struct uart_8250_port *up) static void serial8250_release_port(struct uart_port *port) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); serial8250_release_std_resource(up); if (port->type == PORT_RSA) @@ -2640,8 +2624,7 @@ static void serial8250_release_port(struct uart_port *port) static int serial8250_request_port(struct uart_port *port) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); int ret; if (port->type == PORT_8250_CIR) @@ -2657,10 +2640,149 @@ static int serial8250_request_port(struct uart_port *port) return ret; } -static void serial8250_config_port(struct uart_port *port, int flags) +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(port, struct uart_8250_port, port); + 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); int probeflags = PROBE_ANY; int ret; @@ -2705,6 +2827,9 @@ static void serial8250_config_port(struct uart_port *port, int flags) 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 @@ -2859,8 +2984,7 @@ serial8250_register_ports(struct uart_driver *drv, struct device *dev) static void serial8250_console_putchar(struct uart_port *port, int ch) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); wait_for_xmitr(up, UART_LSR_THRE); serial_port_out(port, UART_TX, ch); |