[POWERPC] CPM_UART: Fix non-console transmit
authorKalle Pokki <kalle.pokki@iki.fi>
Wed, 1 Nov 2006 07:52:41 +0000 (09:52 +0200)
committerPaul Mackerras <paulus@samba.org>
Fri, 10 Nov 2006 10:26:40 +0000 (21:26 +1100)
The SMC and SCC hardware transmitter is enabled at the wrong
place. Simply writing twice to the non-console port, like

$ echo asdf > /dev/ttyCPM1
$ echo asdf > /dev/ttyCPM1

puts the shell into endless uninterruptible sleep, since the
transmitter is stopped after the first write, and is not enabled
before the shutdown function of the second write. Thus the transmit
buffers are never emptied.

Signed-off-by: Kalle Pokki <kalle.pokki@iki.fi>
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
drivers/serial/cpm_uart/cpm_uart_core.c

index 0abb544ae63dbc34a7acc19eaad39c84e5152a17..32fd8c83bd8e59d52bb576f4401b2a095a085d17 100644 (file)
@@ -195,10 +195,8 @@ static void cpm_uart_start_tx(struct uart_port *port)
        if (cpm_uart_tx_pump(port) != 0) {
                if (IS_SMC(pinfo)) {
                        smcp->smc_smcm |= SMCM_TX;
-                       smcp->smc_smcmr |= SMCMR_TEN;
                } else {
                        sccp->scc_sccm |= UART_SCCM_TX;
-                       pinfo->sccp->scc_gsmrl |= SCC_GSMRL_ENT;
                }
        }
 }
@@ -421,9 +419,10 @@ static int cpm_uart_startup(struct uart_port *port)
        /* Startup rx-int */
        if (IS_SMC(pinfo)) {
                pinfo->smcp->smc_smcm |= SMCM_RX;
-               pinfo->smcp->smc_smcmr |= SMCMR_REN;
+               pinfo->smcp->smc_smcmr |= (SMCMR_REN | SMCMR_TEN);
        } else {
                pinfo->sccp->scc_sccm |= UART_SCCM_RX;
+               pinfo->sccp->scc_gsmrl |= (SCC_GSMRL_ENR | SCC_GSMRL_ENT);
        }
 
        if (!(pinfo->flags & FLAG_CONSOLE))