From d1180405c7b5c7a1c6bde79d5fc24fe931430737 Mon Sep 17 00:00:00 2001
From: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Date: Mon, 29 Nov 2021 18:42:38 +0100
Subject: [PATCH] serial: amba-pl011: do not request memory region twice
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Git-commit: d1180405c7b5c7a1c6bde79d5fc24fe931430737
Patch-mainline: v5.17-rc1
References: git-fixes
With commit 3873e2d7f63a ("drivers: PL011: refactor pl011_probe()") the
function devm_ioremap() called from pl011_setup_port() was replaced with
devm_ioremap_resource(). Since this function not only remaps but also
requests the ports io memory region it now collides with the .config_port()
callback which requests the same region at uart port registration.
Since devm_ioremap_resource() already claims the memory successfully, the
request in .config_port() fails.
Later at uart port deregistration the attempt to release the unclaimed
memory also fails. The failure results in a “Trying to free nonexistent
resource" warning.
Fix these issues by removing the callbacks that implement the redundant
memory allocation/release. Also make sure that changing the drivers io
memory base address via TIOCSSERIAL is not allowed any more.
Fixes: 3873e2d7f63a ("drivers: PL011: refactor pl011_probe()")
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20211129174238.8333-1-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/tty/serial/amba-pl011.c | 27 +++------------------------
1 file changed, 3 insertions(+), 24 deletions(-)
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index c9534e229166..e2927a600910 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -2151,32 +2151,13 @@ static const char *pl011_type(struct uart_port *port)
return uap->port.type == PORT_AMBA ? uap->type : NULL;
}
-/*
- * Release the memory region(s) being used by 'port'
- */
-static void pl011_release_port(struct uart_port *port)
-{
- release_mem_region(port->mapbase, SZ_4K);
-}
-
-/*
- * Request the memory region(s) being used by 'port'
- */
-static int pl011_request_port(struct uart_port *port)
-{
- return request_mem_region(port->mapbase, SZ_4K, "uart-pl011")
- != NULL ? 0 : -EBUSY;
-}
-
/*
* Configure/autoconfigure the port.
*/
static void pl011_config_port(struct uart_port *port, int flags)
{
- if (flags & UART_CONFIG_TYPE) {
+ if (flags & UART_CONFIG_TYPE)
port->type = PORT_AMBA;
- pl011_request_port(port);
- }
}
/*
@@ -2191,6 +2172,8 @@ static int pl011_verify_port(struct uart_port *port, struct serial_struct *ser)
ret = -EINVAL;
if (ser->baud_base < 9600)
ret = -EINVAL;
+ if (port->mapbase != (unsigned long) ser->iomem_base)
+ ret = -EINVAL;
return ret;
}
@@ -2243,8 +2226,6 @@ static const struct uart_ops amba_pl011_pops = {
.flush_buffer = pl011_dma_flush_buffer,
.set_termios = pl011_set_termios,
.type = pl011_type,
- .release_port = pl011_release_port,
- .request_port = pl011_request_port,
.config_port = pl011_config_port,
.verify_port = pl011_verify_port,
#ifdef CONFIG_CONSOLE_POLL
@@ -2274,8 +2255,6 @@ static const struct uart_ops sbsa_uart_pops = {
.shutdown = sbsa_uart_shutdown,
.set_termios = sbsa_uart_set_termios,
.type = pl011_type,
- .release_port = pl011_release_port,
- .request_port = pl011_request_port,
.config_port = pl011_config_port,
.verify_port = pl011_verify_port,
#ifdef CONFIG_CONSOLE_POLL
--
2.31.1