[PATCH v2 1/2] serdev: Split and export serdev_acpi_get_uart_resource()

Andy Shevchenko
2021-08-04T14:32:53Z

The same as for I²C Serial Bus resource split and export
serdev_acpi_get_uart_resource(). We have already a few users
one of which is converted here.

Rationale of this is to consolidate parsing UART Serial Bus
resource in one place as it's done, e.g., for I²C Serial Bus.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
---
v2: added Rb tag (Hans)
drivers/tty/serdev/core.c | 36 +++++++++++++++++++++++++++++-------
include/linux/serdev.h | 14 ++++++++++++++
2 files changed, 43 insertions(+), 7 deletions(-)

diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
index 92498961fd92..436e3d1ba92c 100644
--- a/drivers/tty/serdev/core.c
+++ b/drivers/tty/serdev/core.c
@@ -562,23 +562,45 @@ struct acpi_serdev_lookup {
int index;
};

+/**
+ * serdev_acpi_get_uart_resource - Gets UARTSerialBus resource if type matches
+ * @ares: ACPI resource
+ * @uart: Pointer to UARTSerialBus resource will be returned here
+ *
+ * Checks if the given ACPI resource is of type UARTSerialBus.
+ * In this case, returns a pointer to it to the caller.
+ *
+ * Returns true if resource type is of UARTSerialBus, otherwise false.
+ */
+bool serdev_acpi_get_uart_resource(struct acpi_resource *ares,
+ struct acpi_resource_uart_serialbus **uart)
+{
+ struct acpi_resource_uart_serialbus *sb;
+
+ if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
+ return false;
+
+ sb = &ares->data.uart_serial_bus;
+ if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_UART)
+ return false;
+
+ *uart = sb;
+ return true;
+}
+EXPORT_SYMBOL_GPL(serdev_acpi_get_uart_resource);
+
static int acpi_serdev_parse_resource(struct acpi_resource *ares, void *data)
{
struct acpi_serdev_lookup *lookup = data;
struct acpi_resource_uart_serialbus *sb;
acpi_status status;

- if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
- return 1;
-
- if (ares->data.common_serial_bus.type != ACPI_RESOURCE_SERIAL_TYPE_UART)
+ if (!serdev_acpi_get_uart_resource(ares, &sb))
return 1;

if (lookup->index != -1 && lookup->n++ != lookup->index)
return 1;

- sb = &ares->data.uart_serial_bus;
-
status = acpi_get_handle(lookup->device_handle,
sb->resource_source.string_ptr,
&lookup->controller_handle);
@@ -586,7 +608,7 @@ static int acpi_serdev_parse_resource(struct acpi_resource *ares, void *data)
return 1;

/*
- * NOTE: Ideally, we would also want to retreive other properties here,
+ * NOTE: Ideally, we would also want to retrieve other properties here,
* once setting them before opening the device is supported by serdev.
*/

diff --git a/include/linux/serdev.h b/include/linux/serdev.h
index 9f14f9c12ec4..3368c261ab62 100644
--- a/include/linux/serdev.h
+++ b/include/linux/serdev.h
@@ -327,4 +327,18 @@ static inline int serdev_tty_port_unregister(struct tty_port *port)
}
#endif /* CONFIG_SERIAL_DEV_CTRL_TTYPORT */

+struct acpi_resource;
+struct acpi_resource_uart_serialbus;
+
+#ifdef CONFIG_ACPI
+bool serdev_acpi_get_uart_resource(struct acpi_resource *ares,
+ struct acpi_resource_uart_serialbus **uart);
+#else
+static inline bool serdev_acpi_get_uart_resource(struct acpi_resource *ares,
+ struct acpi_resource_uart_serialbus **uart)
+{
+ return false;
+}
+#endif /* CONFIG_ACPI */
+
#endif /*_LINUX_SERDEV_H */
--
2.30.2