[PATCH 07/30] cpm_uart: fix non-console port startup bug

From: Alan Cox
Date: Tue Mar 24 2009 - 10:05:16 EST


From: Xiaotian Feng <Xiaotian.Feng@xxxxxxxxxxxxx>

After UART interrupt handler is installed and rx is enabled, if an rx
interrupt comes before hardware init, rx->cur will be updated. Then the
hardware init will reset BD and make rx->cur out of sync, move the hardware
init code before request_irq.

Signed-off-by: Xiaotian Feng <xiaotian.feng@xxxxxxxxxxxxx>
Signed-off-by: Alan Cox <alan@xxxxxxxxxxxxxxxxxxx>
---

drivers/serial/cpm_uart/cpm_uart_core.c | 14 ++++++++++++--
1 files changed, 12 insertions(+), 2 deletions(-)


diff --git a/drivers/serial/cpm_uart/cpm_uart_core.c b/drivers/serial/cpm_uart/cpm_uart_core.c
index bde4b4b..5c6ef51 100644
--- a/drivers/serial/cpm_uart/cpm_uart_core.c
+++ b/drivers/serial/cpm_uart/cpm_uart_core.c
@@ -406,6 +406,18 @@ static int cpm_uart_startup(struct uart_port *port)

pr_debug("CPM uart[%d]:startup\n", port->line);

+ /* If the port is not the console, make sure rx is disabled. */
+ if (!(pinfo->flags & FLAG_CONSOLE)) {
+ /* Disable UART rx */
+ if (IS_SMC(pinfo)) {
+ clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN);
+ clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX);
+ } else {
+ clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR);
+ clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_RX);
+ }
+ cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX);
+ }
/* Install interrupt handler. */
retval = request_irq(port->irq, cpm_uart_int, 0, "cpm_uart", port);
if (retval)
@@ -420,8 +432,6 @@ static int cpm_uart_startup(struct uart_port *port)
setbits32(&pinfo->sccp->scc_gsmrl, (SCC_GSMRL_ENR | SCC_GSMRL_ENT));
}

- if (!(pinfo->flags & FLAG_CONSOLE))
- cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX);
return 0;
}


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