tty: serial: cpm_uart - fix init when SMC is relocated

[ Upstream commit 06aaa3d066db87e8478522d910285141d44b1e58 ]

SMC relocation can also be activated earlier by the bootloader,
so the driver's behaviour cannot rely on selected kernel config.

When the SMC is relocated, CPM_CR_INIT_TRX cannot be used.

But the only thing CPM_CR_INIT_TRX does is to clear the
rstate and tstate registers, so this can be done manually,
even when SMC is not relocated.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Fixes: 9ab921201444 ("cpm_uart: fix non-console port startup bug")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/tty/serial/cpm_uart/cpm_uart_core.c b/drivers/tty/serial/cpm_uart/cpm_uart_core.c
index 0040c29..b9e137c 100644 (file)
--- a/drivers/tty/serial/cpm_uart/cpm_uart_core.c
+++ b/drivers/tty/serial/cpm_uart/cpm_uart_core.c
@@ -421,7 +421,16 @@ static int cpm_uart_startup(struct uart_port *port)
                        clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_RX);
                }
                cpm_uart_initbd(pinfo);
-               cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX);
+               if (IS_SMC(pinfo)) {
+                       out_be32(&pinfo->smcup->smc_rstate, 0);
+                       out_be32(&pinfo->smcup->smc_tstate, 0);
+                       out_be16(&pinfo->smcup->smc_rbptr,
+                                in_be16(&pinfo->smcup->smc_rbase));
+                       out_be16(&pinfo->smcup->smc_tbptr,
+                                in_be16(&pinfo->smcup->smc_tbase));
+               } else {
+                       cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX);
+               }
        }
        /* Install interrupt handler. */
        retval = request_irq(port->irq, cpm_uart_int, 0, "cpm_uart", port);
@@ -875,16 +884,14 @@ static void cpm_uart_init_smc(struct uart_cpm_port *pinfo)
                 (u8 __iomem *)pinfo->tx_bd_base - DPRAM_BASE);
 
 /*
- *  In case SMC1 is being relocated...
+ *  In case SMC is being relocated...
  */
-#if defined (CONFIG_I2C_SPI_SMC1_UCODE_PATCH)
        out_be16(&up->smc_rbptr, in_be16(&pinfo->smcup->smc_rbase));
        out_be16(&up->smc_tbptr, in_be16(&pinfo->smcup->smc_tbase));
        out_be32(&up->smc_rstate, 0);
        out_be32(&up->smc_tstate, 0);
        out_be16(&up->smc_brkcr, 1);              /* number of break chars */
        out_be16(&up->smc_brkec, 0);
-#endif
 
        /* Set up the uart parameters in the
         * parameter ram.
@@ -898,8 +905,6 @@ static void cpm_uart_init_smc(struct uart_cpm_port *pinfo)
        out_be16(&up->smc_brkec, 0);
        out_be16(&up->smc_brkcr, 1);
 
-       cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX);
-
        /* Set UART mode, 8 bit, no parity, one stop.
         * Enable receive and transmit.
         */