From 05440dfcfcabde6fcf7297dfa5a29f0355b78ffb Mon Sep 17 00:00:00 2001 From: David Brownell Date: Tue, 16 Oct 2007 01:28:21 -0700 Subject: [PATCH] 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: David Brownell Cc: Russell King Cc: Alessandro Zummo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rtc/rtc-cmos.c | 56 +++++++++++++++++++++++------------------- 1 file changed, 31 insertions(+), 25 deletions(-) diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c index 6d0c35397b49..e3fe83a23cf7 100644 --- a/drivers/rtc/rtc-cmos.c +++ b/drivers/rtc/rtc-cmos.c @@ -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 -- 2.20.1