Commit 05440dfc authored by David Brownell's avatar David Brownell Committed by Linus Torvalds
Browse files

rtc-cmos probe() cleanup 



Some cleanups for the rtc-cmos probe logic:

 - Claim i/o ports with request_region() not request_resource(),
   for better coexistence betwen platform and pnp bus glues.

 - Claim those ports earlier, to help work around procfs bugs
   (it allows duplicate names, like /proc/driver/rtc).

 - Fix some glitches in cleanup code, notably a cut'n'paste-o
   where the i/o port region might not get released during
   cleanup after a probe fault.

And some comment clarifications, including noting that this code
must work with PNPBIOS not just PNPACPI..

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 0e36a9a4

drivers/rtc/rtc-cmos.c

+31 −25
Original line number Diff line number Diff line
@@ -433,6 +433,19 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq) 
	if (!ports)

		return -ENODEV;



	/* Claim I/O ports ASAP, minimizing conflict with legacy driver.

	 *

	 * REVISIT non-x86 systems may instead use memory space resources

	 * (needing ioremap etc), not i/o space resources like this ...

	 */

	ports = request_region(ports->start,

			ports->end + 1 - ports->start,

			driver_name);

	if (!ports) {

		dev_dbg(dev, "i/o registers already in use\n");

		return -EBUSY;

	}



	cmos_rtc.irq = rtc_irq;

	cmos_rtc.iomem = ports;
@@ -454,24 +467,13 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq) 


	cmos_rtc.rtc = rtc_device_register(driver_name, dev,

				&cmos_rtc_ops, THIS_MODULE);

	if (IS_ERR(cmos_rtc.rtc))

		return PTR_ERR(cmos_rtc.rtc);

	if (IS_ERR(cmos_rtc.rtc)) {

		retval = PTR_ERR(cmos_rtc.rtc);

		goto cleanup0;

	}



	cmos_rtc.dev = dev;

	dev_set_drvdata(dev, &cmos_rtc);



	/* platform and pnp busses handle resources incompatibly.

	 *

	 * REVISIT for non-x86 systems we may need to handle io memory

	 * resources: ioremap them, and request_mem_region().

	 */

	if (is_pnp()) {

		retval = request_resource(&ioport_resource, ports);

		if (retval < 0) {

			dev_dbg(dev, "i/o registers already in use\n");

			goto cleanup0;

		}

	}

	rename_region(ports, cmos_rtc.rtc->dev.bus_id);



	spin_lock_irq(&rtc_lock);
@@ -534,9 +536,10 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq) 
	return 0;



cleanup1:

	rename_region(ports, NULL);

cleanup0:

	cmos_rtc.dev = NULL;

	rtc_device_unregister(cmos_rtc.rtc);

cleanup0:

	release_region(ports->start, ports->end + 1 - ports->start);

	return retval;

}
@@ -555,19 +558,21 @@ static void cmos_do_shutdown(void) 
static void __exit cmos_do_remove(struct device *dev)

{

	struct cmos_rtc	*cmos = dev_get_drvdata(dev);

	struct resource *ports;



	cmos_do_shutdown();



	if (is_pnp())

		release_resource(cmos->iomem);

	rename_region(cmos->iomem, NULL);



	if (is_valid_irq(cmos->irq))

		free_irq(cmos->irq, cmos_rtc.rtc);

		free_irq(cmos->irq, cmos->rtc);



	rtc_device_unregister(cmos_rtc.rtc);

	rtc_device_unregister(cmos->rtc);

	cmos->rtc = NULL;



	cmos_rtc.dev = NULL;

	ports = cmos->iomem;

	release_region(ports->start, ports->end + 1 - ports->start);

	cmos->iomem = NULL;



	cmos->dev = NULL;

	dev_set_drvdata(dev, NULL);

}
@@ -654,7 +659,8 @@ static int cmos_resume(struct device *dev) 
/*----------------------------------------------------------------*/



/* The "CMOS" RTC normally lives on the platform_bus.  On ACPI systems,

 * the device node will always be created as a PNPACPI device.

 * the device node will always be created as a PNPACPI device.  Plus

 * pre-ACPI PCs probably list it in the PNPBIOS tables.

 */



#ifdef	CONFIG_PNP

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