[PATCH 5/8] drivers: tty: serial: introduce struct resource

From: Enrico Weigelt, metux IT consult
Date: Tue Mar 12 2019 - 10:58:53 EST


The standard data structure for holding io resources in the
kernel is struct resource. Serial drivers yet don't really
use it (except when retrieving from oftree).

This patch introduces a new field in struct uart_port for that,
plus several helpers. Yet it's up to the individual drivers for
using it - serial_core doesn't care yet. Therefore, the old fields
mapbase and mapsize need to be filled properly by the drivers.
---
include/linux/serial_core.h | 49 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 49 insertions(+)

diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 5fe2b03..9b07a40 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -24,6 +24,7 @@
#include <linux/compiler.h>
#include <linux/console.h>
#include <linux/interrupt.h>
+#include <linux/ioport.h>
#include <linux/circ_buf.h>
#include <linux/spinlock.h>
#include <linux/sched.h>
@@ -256,6 +257,7 @@ struct uart_port {
unsigned int minor;
resource_size_t mapbase; /* for ioremap */
resource_size_t mapsize;
+ struct resource memres;
struct device *dev; /* parent device */
unsigned char hub6; /* this should be in the 8250 driver */
unsigned char suspended;
@@ -427,6 +429,53 @@ void uart_console_write(struct uart_port *port, const char *s,
int uart_match_port(struct uart_port *port1, struct uart_port *port2);

/*
+ * Port resource management
+ */
+static inline void uart_memres_set(struct uart_port *port,
+ struct resource res)
+{
+ port->memres = res;
+ port->mapbase = res.start;
+}
+
+static inline void uart_memres_clear(struct uart_port *port)
+{
+ port->memres = DEFINE_RES_MEM(0, 0);
+}
+
+static inline int uart_memres_valid(struct uart_port *port)
+{
+ return (port->memres.start != 0);
+}
+
+static inline struct resource *uart_memres_request(struct uart_port *port,
+ const char *name)
+{
+ return request_mem_region(
+ port->memres.start,
+ resource_size(&port->memres),
+ name);
+}
+
+static inline void uart_memres_release(struct uart_port *port)
+{
+ return release_mem_region(port->memres.start,
+ resource_size(&port->memres));
+}
+
+static inline void __iomem *uart_memres_ioremap_nocache(struct uart_port *port)
+{
+ return ioremap_nocache(port->memres.start,
+ resource_size(&port->memres.start));
+}
+
+static inline void __iomem *uart_memres_ioremap(struct uart_port *port)
+{
+ return ioremap(port->memres.start,
+ resource_size(&port->memres.start));
+}
+
+/*
* Power Management
*/
int uart_suspend_port(struct uart_driver *reg, struct uart_port *port);
--
1.9.1