diff options
Diffstat (limited to 'drivers/tty/serial/cpm_uart/cpm_uart_core.c')
| -rw-r--r-- | drivers/tty/serial/cpm_uart/cpm_uart_core.c | 23 |
1 files changed, 19 insertions, 4 deletions
diff --git a/drivers/tty/serial/cpm_uart/cpm_uart_core.c b/drivers/tty/serial/cpm_uart/cpm_uart_core.c index b418947b7107..d0dd9194cecc 100644 --- a/drivers/tty/serial/cpm_uart/cpm_uart_core.c +++ b/drivers/tty/serial/cpm_uart/cpm_uart_core.c @@ -71,7 +71,7 @@ static void cpm_uart_initbd(struct uart_cpm_port *pinfo); /**************************************************************/ -#define HW_BUF_SPD_THRESHOLD 9600 +#define HW_BUF_SPD_THRESHOLD 2400 /* * Check, if transmit buffers are processed @@ -417,6 +417,7 @@ static int cpm_uart_startup(struct uart_port *port) clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR); clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_RX); } + cpm_uart_initbd(pinfo); cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX); } /* Install interrupt handler. */ @@ -500,16 +501,28 @@ static void cpm_uart_set_termios(struct uart_port *port, struct uart_cpm_port *pinfo = (struct uart_cpm_port *)port; smc_t __iomem *smcp = pinfo->smcp; scc_t __iomem *sccp = pinfo->sccp; + int maxidl; pr_debug("CPM uart[%d]:set_termios\n", port->line); baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16); - if (baud <= HW_BUF_SPD_THRESHOLD || + if (baud < HW_BUF_SPD_THRESHOLD || (pinfo->port.state && pinfo->port.state->port.tty->low_latency)) pinfo->rx_fifosize = 1; else pinfo->rx_fifosize = RX_BUF_SIZE; + /* MAXIDL is the timeout after which a receive buffer is closed + * when not full if no more characters are received. + * We calculate it from the baudrate so that the duration is + * always the same at standard rates: about 4ms. + */ + maxidl = baud / 2400; + if (maxidl < 1) + maxidl = 1; + if (maxidl > 0x10) + maxidl = 0x10; + /* Character length programmed into the mode register is the * sum of: 1 start bit, number of data bits, 0 or 1 parity bit, * 1 or 2 stop bits, minus 1. @@ -610,6 +623,7 @@ static void cpm_uart_set_termios(struct uart_port *port, * SMC/SCC receiver is disabled. */ out_be16(&pinfo->smcup->smc_mrblr, pinfo->rx_fifosize); + out_be16(&pinfo->smcup->smc_maxidl, maxidl); /* Set the mode register. We want to keep a copy of the * enables, because we want to put them back if they were @@ -622,6 +636,7 @@ static void cpm_uart_set_termios(struct uart_port *port, SMCMR_SM_UART | prev_mode); } else { out_be16(&pinfo->sccup->scc_genscc.scc_mrblr, pinfo->rx_fifosize); + out_be16(&pinfo->sccup->scc_maxidl, maxidl); out_be16(&sccp->scc_psmr, (sbits << 12) | scval); } @@ -798,7 +813,7 @@ static void cpm_uart_init_scc(struct uart_cpm_port *pinfo) cpm_set_scc_fcr(sup); out_be16(&sup->scc_genscc.scc_mrblr, pinfo->rx_fifosize); - out_be16(&sup->scc_maxidl, pinfo->rx_fifosize); + out_be16(&sup->scc_maxidl, 0x10); out_be16(&sup->scc_brkcr, 1); out_be16(&sup->scc_parec, 0); out_be16(&sup->scc_frmec, 0); @@ -872,7 +887,7 @@ static void cpm_uart_init_smc(struct uart_cpm_port *pinfo) /* Using idle character time requires some additional tuning. */ out_be16(&up->smc_mrblr, pinfo->rx_fifosize); - out_be16(&up->smc_maxidl, pinfo->rx_fifosize); + out_be16(&up->smc_maxidl, 0x10); out_be16(&up->smc_brklen, 0); out_be16(&up->smc_brkec, 0); out_be16(&up->smc_brkcr, 1); |