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Remove UPF_RESOURCES

CFT Russell King 1 participant 1 message Jun 29, 2004 TTY layer and serial drivers

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Russell King

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The UPF_RESOURCES flag was added to the serial layer to cater for the idiosyncrasies of the PCMCIA layer, where the PCMCIA core code handles the claiming of busy resources.

However, the PCMCIA core has progressed, and now does not claim busy resources - IOW, it now behaves just like any other bus driver, where resources are allocated non-busy and its up to the drivers to mark their regions busy using request_region / request_mem_region.

The effect of this is that the UPF_RESOURCES hack in the serial layer is now redundant, and can now be removed - 8250 devices should now always use request_region / request_mem_region unconditionally.

In theory, this should only affect the 8250 driver, but I see some other drivers (au1x00) also using this flag. However, since this flag is always set in the driver, it's rather pointless.

(Of course, this all assumes that you're using Linus' latest BK or akpm's -mm2 or later, which has the necessary PCMCIA changes in place.)

akpm - feel free to apply to -mm.

So, here's a patch which removes the UPF_RESOURCES entirely:

===== drivers/serial/8250.c 1.55 vs edited =====

drivers/serial/8250.c +12 -21
@@ -1687,8 +1687,6 @@
 	struct uart_8250_port *up = (struct uart_8250_port *)port;
 	unsigned long start, offset = 0, size = 0;
 
-	if (!(up->port.flags & UPF_RESOURCES))
-		return;
 	if (up->port.type == PORT_RSA) {
 		offset = UART_RSA_BASE << up->port.regshift;
 		size = 8;

@@ -1733,16 +1731,14 @@
 	struct resource *res = NULL, *res_rsa = NULL;
 	int ret = 0;
 
-	if (up->port.flags & UPF_RESOURCES) {
-		if (up->port.type == PORT_RSA) {
-			ret = serial8250_request_rsa_resource(up, &res_rsa);
-			if (ret < 0)
-				return ret;
-		}
-
-		ret = serial8250_request_std_resource(up, &res);
+	if (up->port.type == PORT_RSA) {
+		ret = serial8250_request_rsa_resource(up, &res_rsa);
+		if (ret < 0)
+			return ret;
 	}
 
+	ret = serial8250_request_std_resource(up, &res);
+
 	/*
 	 * If we have a mapbase, then request that as well.
 	 */

@@ -1782,17 +1778,13 @@
 	 * Find the region that we can probe for.  This in turn
 	 * tells us whether we can probe for the type of port.
 	 */
-	if (up->port.flags & UPF_RESOURCES) {
-		ret = serial8250_request_std_resource(up, &res_std);
-		if (ret < 0)
-			return;
+	ret = serial8250_request_std_resource(up, &res_std);
+	if (ret < 0)
+		return;
 
-		ret = serial8250_request_rsa_resource(up, &res_rsa);
-		if (ret < 0)
-			probeflags &= ~PROBE_RSA;
-	} else {
+	ret = serial8250_request_rsa_resource(up, &res_rsa);
+	if (ret < 0)
 		probeflags &= ~PROBE_RSA;
-	}
 
 	if (flags & UART_CONFIG_TYPE)
 		autoconfig(up, probeflags);

@@ -1867,8 +1859,7 @@
 		up->port.iobase   = old_serial_port[i].port;
 		up->port.irq      = irq_canonicalize(old_serial_port[i].irq);
 		up->port.uartclk  = old_serial_port[i].baud_base * 16;
-		up->port.flags    = old_serial_port[i].flags |
-				    UPF_RESOURCES;
+		up->port.flags    = old_serial_port[i].flags;
 		up->port.hub6     = old_serial_port[i].hub6;
 		up->port.membase  = old_serial_port[i].iomem_base;
 		up->port.iotype   = old_serial_port[i].io_type;

===== drivers/serial/8250_acorn.c 1.4 vs edited =====

drivers/serial/8250_acorn.c +1 -2
@@ -43,8 +43,7 @@
 
 	memset(&req, 0, sizeof(req));
 	req.irq			= irq;
-	req.flags		= UPF_AUTOPROBE | UPF_RESOURCES |
-				  UPF_SHARE_IRQ;
+	req.flags		= UPF_AUTOPROBE | UPF_SHARE_IRQ;
 	req.baud_base		= baud_base;
 	req.io_type		= UPIO_MEM;
 	req.iomem_base		= vaddr;

===== drivers/serial/8250_acpi.c 1.10 vs edited =====

drivers/serial/8250_acpi.c +1 -1
@@ -123,7 +123,7 @@
 	}
 
 	serial_req.baud_base = BASE_BAUD;
-	serial_req.flags = UPF_SKIP_TEST | UPF_BOOT_AUTOCONF | UPF_RESOURCES;
+	serial_req.flags = UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
 
 	priv->line = register_serial(&serial_req);
 	if (priv->line < 0) {

===== drivers/serial/8250_pci.c 1.35 vs edited =====

drivers/serial/8250_pci.c +1 -1
@@ -1665,7 +1665,7 @@
 	for (i = 0; i < nr_ports; i++) {
 		memset(&serial_req, 0, sizeof(serial_req));
 		serial_req.flags = UPF_SKIP_TEST | UPF_AUTOPROBE |
-				   UPF_RESOURCES | UPF_SHARE_IRQ;
+				   UPF_SHARE_IRQ;
 		serial_req.baud_base = board->base_baud;
 		serial_req.irq = get_pci_irq(dev, board, i);
 		if (quirk->setup(dev, board, &serial_req, i))

===== drivers/serial/8250_pnp.c 1.22 vs edited =====

drivers/serial/8250_pnp.c +1 -1
@@ -413,7 +413,7 @@
 	       serial_req.port, serial_req.irq, serial_req.io_type);
 #endif
 
-	serial_req.flags = UPF_SKIP_TEST | UPF_AUTOPROBE  | UPF_RESOURCES;
+	serial_req.flags = UPF_SKIP_TEST | UPF_AUTOPROBE;
 	serial_req.baud_base = 115200;
 	line = register_serial(&serial_req);

===== drivers/serial/au1x00_uart.c 1.1 vs edited =====

drivers/serial/au1x00_uart.c +2 -5
@@ -969,9 +969,7 @@
 	struct resource *res = NULL, *res_rsa = NULL;
 	int ret = 0;
 
-	if (up->port.flags & UPF_RESOURCES) {
-		ret = serial8250_request_std_resource(up, &res);
-	}
+	ret = serial8250_request_std_resource(up, &res);
 
 	/*
 	 * If we have a mapbase, then request that as well.

@@ -1072,8 +1070,7 @@
 		up->port.iobase   = old_serial_port[i].port;
 		up->port.irq      = old_serial_port[i].irq;
 		up->port.uartclk  = get_au1x00_uart_baud_base();
-		up->port.flags    = old_serial_port[i].flags |
-				    UPF_RESOURCES;
+		up->port.flags    = old_serial_port[i].flags;
 		up->port.hub6     = old_serial_port[i].hub6;
 		up->port.membase  = old_serial_port[i].iomem_base;
 		up->port.iotype   = old_serial_port[i].io_type;

===== drivers/serial/bast_sio.c 1.1 vs edited =====

drivers/serial/bast_sio.c +1 -1
@@ -24,7 +24,7 @@
 	printk("BAST: SuperIO serial (%08lx,%d)\n", port, irq);
 #endif
 
-	serial_req.flags      = UPF_AUTOPROBE | UPF_RESOURCES | UPF_SHARE_IRQ;
+	serial_req.flags      = UPF_AUTOPROBE | UPF_SHARE_IRQ;
 	serial_req.baud_base  = BASE_BAUD;
 	serial_req.irq        = irq;
 	serial_req.io_type    = UPIO_MEM;

===== include/linux/serial_core.h 1.40 vs edited =====

include/linux/serial_core.h +0 -1
@@ -205,7 +205,6 @@
 #define UPF_CONS_FLOW		(1 << 23)
 #define UPF_SHARE_IRQ		(1 << 24)
 #define UPF_BOOT_AUTOCONF	(1 << 28)
-#define UPF_RESOURCES		(1 << 30)
 #define UPF_IOREMAP		(1 << 31)
 
 #define UPF_CHANGE_MASK		(0x17fff)
Signature · 4 lines
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:  2.6 PCMCIA      - http://pcmcia.arm.linux.org.uk/
                 2.6 Serial core