[PATCH V4 2/5] tty: serial: meson: Request the register

From: Yu Tu
Date: Mon Jan 10 2022 - 03:58:19 EST


This simplifies resetting the UART controller during probe and
will make it easier to integrate the common clock code which
will require the registers at probe time as well.

Signed-off-by: Yu Tu <yu.tu@xxxxxxxxxxx>
---
drivers/tty/serial/meson_uart.c | 24 ++++++------------------
1 file changed, 6 insertions(+), 18 deletions(-)

diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index 45e00d928253..7570958d010c 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -395,24 +395,11 @@ static int meson_uart_verify_port(struct uart_port *port,

static void meson_uart_release_port(struct uart_port *port)
{
- devm_iounmap(port->dev, port->membase);
- port->membase = NULL;
- devm_release_mem_region(port->dev, port->mapbase, port->mapsize);
+ /* nothing to do */
}

static int meson_uart_request_port(struct uart_port *port)
{
- if (!devm_request_mem_region(port->dev, port->mapbase, port->mapsize,
- dev_name(port->dev))) {
- dev_err(port->dev, "Memory region busy\n");
- return -EBUSY;
- }
-
- port->membase = devm_ioremap(port->dev, port->mapbase,
- port->mapsize);
- if (!port->membase)
- return -ENOMEM;
-
return 0;
}

@@ -733,6 +720,10 @@ static int meson_uart_probe(struct platform_device *pdev)
if (!port)
return -ENOMEM;

+ port->membase = devm_ioremap_resource(&pdev->dev, res_mem);
+ if (IS_ERR(port->membase))
+ return PTR_ERR(port->membase);
+
ret = meson_uart_probe_clocks(pdev, port);
if (ret)
return ret;
@@ -754,10 +745,7 @@ static int meson_uart_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, port);

/* reset port before registering (and possibly registering console) */
- if (meson_uart_request_port(port) >= 0) {
- meson_uart_reset(port);
- meson_uart_release_port(port);
- }
+ meson_uart_reset(port);

ret = uart_add_one_port(&meson_uart_driver, port);
if (ret)
--
2.33.1