[PATCH v2 12/15] tty: serial: provide devm_uart_add_one_port()

Bartosz Golaszewski
2022-11-22T10:23:57Z

Provide a devres variant of uart_add_one_port() that removes the managed
port at device detach.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---
.../driver-api/driver-model/devres.rst | 3 ++
drivers/tty/serial/serial_core.c | 36 +++++++++++++++++++
include/linux/serial_core.h | 6 ++++
3 files changed, 45 insertions(+)

diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst
index 56082265e8e5..5d07a8c1eadb 100644
--- a/Documentation/driver-api/driver-model/devres.rst
+++ b/Documentation/driver-api/driver-model/devres.rst
@@ -436,6 +436,9 @@ RTC
SERDEV
devm_serdev_device_open()

+SERIAL
+ devm_uart_add_one_port()
+
SLAVE DMA ENGINE
devm_acpi_dma_controller_register()

diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 179ee199df34..005190b279b3 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -3217,6 +3217,42 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport)
}
EXPORT_SYMBOL(uart_remove_one_port);

+struct uart_port_devres {
+ struct uart_driver *drv;
+ struct uart_port *port;
+};
+
+static void devm_uart_remove_one_port(struct device *dev, void *data)
+{
+ struct uart_port_devres *res = data;
+
+ uart_remove_one_port(res->drv, res->port);
+}
+
+int devm_uart_add_one_port(struct device *dev,
+ struct uart_driver *drv, struct uart_port *port)
+{
+ struct uart_port_devres *res;
+ int ret;
+
+ res = devres_alloc(devm_uart_remove_one_port, sizeof(*res), GFP_KERNEL);
+ if (!res)
+ return -1;
+
+ ret = uart_add_one_port(drv, port);
+ if (ret) {
+ devres_free(res);
+ return -1;
+ }
+
+ res->drv = drv;
+ res->port = port;
+ devres_add(dev, res);
+
+ return 0;
+}
+EXPORT_SYMBOL(devm_uart_add_one_port);
+
/**
* uart_match_port - are the two ports equivalent?
* @port1: first port
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index d657f2a42a7b..d0911f04706e 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -771,6 +771,12 @@ int uart_remove_one_port(struct uart_driver *reg, struct uart_port *port);
bool uart_match_port(const struct uart_port *port1,
const struct uart_port *port2);

+/*
+ * UART devres
+ */
+int devm_uart_add_one_port(struct device *dev,
+ struct uart_driver *drv, struct uart_port *port);
+
/*
* Power Management
*/
--
2.37.2