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authorHugo Villeneuve2023-08-07 17:45:51 -0400
committerGreg Kroah-Hartman2023-09-06 21:27:02 +0100
commit682f9b944374fbdc7ee18b41ec8feb146746c433 (patch)
tree497501aa2f5a5697578ecbb6518cbaf76a12e639
parent4b3de7d2f86910a92377d2b4dda86c3c38c48e3d (diff)
serial: sc16is7xx: fix broken port 0 uart init
commit 2861ed4d6e6d1a2c9de9bf5b0abd996c2dc673d0 upstream. The sc16is7xx_config_rs485() function is called only for the second port (index 1, channel B), causing initialization problems for the first port. For the sc16is7xx driver, port->membase and port->mapbase are not set, and their default values are 0. And we set port->iobase to the device index. This means that when the first device is registered using the uart_add_one_port() function, the following values will be in the port structure: port->membase = 0 port->mapbase = 0 port->iobase = 0 Therefore, the function uart_configure_port() in serial_core.c will exit early because of the following check: /* * If there isn't a port here, don't do anything further. */ if (!port->iobase && !port->mapbase && !port->membase) return; Typically, I2C and SPI drivers do not set port->membase and port->mapbase. The max310x driver sets port->membase to ~0 (all ones). By implementing the same change in this driver, uart_configure_port() is now correctly executed for all ports. Fixes: dfeae619d781 ("serial: sc16is7xx") Cc: stable@vger.kernel.org Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Lech Perczak <lech.perczak@camlingroup.com> Tested-by: Lech Perczak <lech.perczak@camlingroup.com> Link: https://lore.kernel.org/r/20230807214556.540627-2-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/tty/serial/sc16is7xx.c6
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 93cf5f788817..58b565a12836 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -1439,6 +1439,12 @@ static int sc16is7xx_probe(struct device *dev,
s->p[i].port.fifosize = SC16IS7XX_FIFO_SIZE;
s->p[i].port.flags = UPF_FIXED_TYPE | UPF_LOW_LATENCY;
s->p[i].port.iobase = i;
+ /*
+ * Use all ones as membase to make sure uart_configure_port() in
+ * serial_core.c does not abort for SPI/I2C devices where the
+ * membase address is not applicable.
+ */
+ s->p[i].port.membase = (void __iomem *)~0;
s->p[i].port.iotype = UPIO_PORT;
s->p[i].port.uartclk = freq;
s->p[i].port.rs485_config = sc16is7xx_config_rs485;