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serial: amba-pl011: do not request memory region twice

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[ Upstream commit d1180405c7b5c7a1c6bde79d5fc24fe931430737 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Lino Sanfilippo 2021-11-29 18:42:38 +01:00 committed by Greg Kroah-Hartman
parent 7b54c97579
commit aee7ef0305
1 changed files with 3 additions and 24 deletions
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27
drivers/tty/serial/amba-pl011.c
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@ -2183,32 +2183,13 @@ 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);
}
}
/*
@ -2223,6 +2204,8 @@ 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;
}
@ -2275,8 +2258,6 @@ 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
@ -2306,8 +2287,6 @@ 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