diff options
Diffstat (limited to 'drivers/tty/serial/sh-sci.c')
-rw-r--r-- | drivers/tty/serial/sh-sci.c | 88 |
1 files changed, 67 insertions, 21 deletions
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index 5b50c792ad5f..e7d6566fafaf 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -844,14 +844,32 @@ static int sci_handle_fifo_overrun(struct uart_port *port) struct tty_port *tport = &port->state->port; struct sci_port *s = to_sci_port(port); struct plat_sci_reg *reg; - int copied = 0; + int copied = 0, offset; + u16 status, bit; + + switch (port->type) { + case PORT_SCIF: + case PORT_HSCIF: + offset = SCLSR; + break; + case PORT_SCIFA: + case PORT_SCIFB: + offset = SCxSR; + break; + default: + return 0; + } - reg = sci_getreg(port, SCLSR); + reg = sci_getreg(port, offset); if (!reg->size) return 0; - if ((serial_port_in(port, SCLSR) & (1 << s->overrun_bit))) { - serial_port_out(port, SCLSR, 0); + status = serial_port_in(port, offset); + bit = 1 << s->overrun_bit; + + if (status & bit) { + status &= ~bit; + serial_port_out(port, offset, status); port->icount.overrun++; @@ -996,16 +1014,24 @@ static inline unsigned long port_rx_irq_mask(struct uart_port *port) static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr) { - unsigned short ssr_status, scr_status, err_enabled; - unsigned short slr_status = 0; + unsigned short ssr_status, scr_status, err_enabled, orer_status = 0; struct uart_port *port = ptr; struct sci_port *s = to_sci_port(port); irqreturn_t ret = IRQ_NONE; ssr_status = serial_port_in(port, SCxSR); scr_status = serial_port_in(port, SCSCR); - if (port->type == PORT_SCIF || port->type == PORT_HSCIF) - slr_status = serial_port_in(port, SCLSR); + switch (port->type) { + case PORT_SCIF: + case PORT_HSCIF: + orer_status = serial_port_in(port, SCLSR); + break; + case PORT_SCIFA: + case PORT_SCIFB: + orer_status = ssr_status; + break; + } + err_enabled = scr_status & port_rx_irq_mask(port); /* Tx Interrupt */ @@ -1033,10 +1059,8 @@ static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr) ret = sci_br_interrupt(irq, ptr); /* Overrun Interrupt */ - if (port->type == PORT_SCIF || port->type == PORT_HSCIF) { - if (slr_status & 0x01) - sci_handle_fifo_overrun(port); - } + if (orer_status & (1 << s->overrun_bit)) + sci_handle_fifo_overrun(port); return ret; } @@ -1967,18 +1991,40 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios, #ifdef CONFIG_SERIAL_SH_SCI_DMA /* - * Calculate delay for 1.5 DMA buffers: see - * drivers/serial/serial_core.c::uart_update_timeout(). With 10 bits - * (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above function + * Calculate delay for 2 DMA buffers (4 FIFO). + * See drivers/serial/serial_core.c::uart_update_timeout(). With 10 + * bits (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above function * calculates 1 jiffie for the data plus 5 jiffies for the "slop(e)." - * Then below we calculate 3 jiffies (12ms) for 1.5 DMA buffers (3 FIFO - * sizes), but it has been found out experimentally, that this is not - * enough: the driver too often needlessly runs on a DMA timeout. 20ms - * as a minimum seem to work perfectly. + * Then below we calculate 5 jiffies (20ms) for 2 DMA buffers (4 FIFO + * sizes), but when performing a faster transfer, value obtained by + * this formula is may not enough. Therefore, if value is smaller than + * 20msec, this sets 20msec as timeout of DMA. */ if (s->chan_rx) { - s->rx_timeout = (port->timeout - HZ / 50) * s->buf_len_rx * 3 / - port->fifosize / 2; + unsigned int bits; + + /* byte size and parity */ + switch (termios->c_cflag & CSIZE) { + case CS5: + bits = 7; + break; + case CS6: + bits = 8; + break; + case CS7: + bits = 9; + break; + default: + bits = 10; + break; + } + + if (termios->c_cflag & CSTOPB) + bits++; + if (termios->c_cflag & PARENB) + bits++; + s->rx_timeout = DIV_ROUND_UP((s->buf_len_rx * 2 * bits * HZ) / + (baud / 10), 10); dev_dbg(port->dev, "DMA Rx t-out %ums, tty t-out %u jiffies\n", s->rx_timeout * 1000 / HZ, port->timeout); if (s->rx_timeout < msecs_to_jiffies(20)) |