bus: Make remove callback return void

The driver core ignores the return value of this callback because there
is only little it can do when a device disappears.

This is the final bit of a long lasting cleanup quest where several
buses were converted to also return void from their remove callback.
Additionally some resource leaks were fixed that were caused by drivers
returning an error code in the expectation that the driver won't go
away.

With struct bus_type::remove returning void it's prevented that newly
implemented buses return an ignored error code and so don't anticipate
wrong expectations for driver authors.

Reviewed-by: Tom Rix <trix@redhat.com> (For fpga)
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com> (For drivers/s390 and drivers/vfio)
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> (For ARM, Amba and related parts)
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Chen-Yu Tsai <wens@csie.org> (for sunxi-rsb)
Acked-by: Pali Rohár <pali@kernel.org>
Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org> (for media)
Acked-by: Hans de Goede <hdegoede@redhat.com> (For drivers/platform)
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-By: Vinod Koul <vkoul@kernel.org>
Acked-by: Juergen Gross <jgross@suse.com> (For xen)
Acked-by: Lee Jones <lee.jones@linaro.org> (For mfd)
Acked-by: Johannes Thumshirn <jth@kernel.org> (For mcb)
Acked-by: Johan Hovold <johan@kernel.org>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> (For slimbus)
Acked-by: Kirti Wankhede <kwankhede@nvidia.com> (For vfio)
Acked-by: Maximilian Luz <luzmaximilian@gmail.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> (For ulpi and typec)
Acked-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com> (For ipack)
Acked-by: Geoff Levand <geoff@infradead.org> (For ps3)
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com> (For thunderbolt)
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> (For intel_th)
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net> (For pcmcia)
Acked-by: Rafael J. Wysocki <rafael@kernel.org> (For ACPI)
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org> (rpmsg and apr)
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> (For intel-ish-hid)
Acked-by: Dan Williams <dan.j.williams@intel.com> (For CXL, DAX, and NVDIMM)
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> (For isa)
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (For firewire)
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> (For hid)
Acked-by: Thorsten Scherer <t.scherer@eckelmann.de> (For siox)
Acked-by: Sven Van Asbroeck <TheSven73@gmail.com> (For anybuss)
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> (For MMC)
Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Finn Thain <fthain@linux-m68k.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210713193522.1770306-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/arm/common/locomo.c

@@ -834,14 +834,13 @@ static int locomo_bus_probe(struct device *dev)
 	return ret;
 }
 
-static int locomo_bus_remove(struct device *dev)
+static void locomo_bus_remove(struct device *dev)
 {
 	struct locomo_dev *ldev = LOCOMO_DEV(dev);
 	struct locomo_driver *drv = LOCOMO_DRV(dev->driver);
 
 	if (drv->remove)
 		drv->remove(ldev);
-	return 0;
 }
 
 struct bus_type locomo_bus_type = {

arch/arm/common/sa1111.c

@@ -1364,15 +1364,13 @@ static int sa1111_bus_probe(struct device *dev)
 	return ret;
 }
 
-static int sa1111_bus_remove(struct device *dev)
+static void sa1111_bus_remove(struct device *dev)
 {
 	struct sa1111_dev *sadev = to_sa1111_device(dev);
 	struct sa1111_driver *drv = SA1111_DRV(dev->driver);
 
 	if (drv->remove)
 		drv->remove(sadev);
-
-	return 0;
 }
 
 struct bus_type sa1111_bus_type = {

arch/arm/mach-rpc/ecard.c

@@ -1052,7 +1052,7 @@ static int ecard_drv_probe(struct device *dev)
 	return ret;
 }
 
-static int ecard_drv_remove(struct device *dev)
+static void ecard_drv_remove(struct device *dev)
 {
 	struct expansion_card *ec = ECARD_DEV(dev);
 	struct ecard_driver *drv = ECARD_DRV(dev->driver);
@@ -1067,8 +1067,6 @@ static int ecard_drv_remove(struct device *dev)
 	ec->ops = &ecard_default_ops;
 	barrier();
 	ec->irq_data = NULL;
-
-	return 0;
 }
 
 /*

arch/mips/sgi-ip22/ip22-gio.c

@@ -143,14 +143,13 @@ static int gio_device_probe(struct device *dev)
 	return error;
 }
 
-static int gio_device_remove(struct device *dev)
+static void gio_device_remove(struct device *dev)
 {
 	struct gio_device *gio_dev = to_gio_device(dev);
 	struct gio_driver *drv = to_gio_driver(dev->driver);
 
 	if (dev->driver && drv->remove)
 		drv->remove(gio_dev);
-	return 0;
 }
 
 static void gio_device_shutdown(struct device *dev)

arch/parisc/kernel/drivers.c

@@ -133,14 +133,13 @@ static int parisc_driver_probe(struct device *dev)
 	return rc;
 }
 
-static int __exit parisc_driver_remove(struct device *dev)
+static void __exit parisc_driver_remove(struct device *dev)
 {
 	struct parisc_device *pa_dev = to_parisc_device(dev);
 	struct parisc_driver *pa_drv = to_parisc_driver(dev->driver);
+
 	if (pa_drv->remove)
 		pa_drv->remove(pa_dev);
-
-	return 0;
 }
 	
 

arch/powerpc/platforms/ps3/system-bus.c

@@ -381,7 +381,7 @@ static int ps3_system_bus_probe(struct device *_dev)
 	return result;
 }
 
-static int ps3_system_bus_remove(struct device *_dev)
+static void ps3_system_bus_remove(struct device *_dev)
 {
 	struct ps3_system_bus_device *dev = ps3_dev_to_system_bus_dev(_dev);
 	struct ps3_system_bus_driver *drv;
@@ -399,7 +399,6 @@ static int ps3_system_bus_remove(struct device *_dev)
 			__func__, __LINE__, drv->core.name);
 
 	pr_debug(" <- %s:%d: %s\n", __func__, __LINE__, dev_name(&dev->core));
-	return 0;
 }
 
 static void ps3_system_bus_shutdown(struct device *_dev)

arch/powerpc/platforms/pseries/ibmebus.c

@@ -366,14 +366,13 @@ static int ibmebus_bus_device_probe(struct device *dev)
 	return error;
 }
 
-static int ibmebus_bus_device_remove(struct device *dev)
+static void ibmebus_bus_device_remove(struct device *dev)
 {
 	struct platform_device *of_dev = to_platform_device(dev);
 	struct platform_driver *drv = to_platform_driver(dev->driver);
 
 	if (dev->driver && drv->remove)
 		drv->remove(of_dev);
-	return 0;
 }
 
 static void ibmebus_bus_device_shutdown(struct device *dev)

arch/powerpc/platforms/pseries/vio.c

@@ -1257,7 +1257,7 @@ static int vio_bus_probe(struct device *dev)
 }
 
 /* convert from struct device to struct vio_dev and pass to driver. */
-static int vio_bus_remove(struct device *dev)
+static void vio_bus_remove(struct device *dev)
 {
 	struct vio_dev *viodev = to_vio_dev(dev);
 	struct vio_driver *viodrv = to_vio_driver(dev->driver);
@@ -1276,7 +1276,6 @@ static int vio_bus_remove(struct device *dev)
 		vio_cmo_bus_remove(viodev);
 
 	put_device(devptr);
-	return 0;
 }
 
 static void vio_bus_shutdown(struct device *dev)

arch/sparc/kernel/vio.c

@@ -93,7 +93,7 @@ static int vio_device_probe(struct device *dev)
 	return drv->probe(vdev, id);
 }
 
-static int vio_device_remove(struct device *dev)
+static void vio_device_remove(struct device *dev)
 {
 	struct vio_dev *vdev = to_vio_dev(dev);
 	struct vio_driver *drv = to_vio_driver(dev->driver);
@@ -107,8 +107,6 @@ static int vio_device_remove(struct device *dev)
 
 		drv->remove(vdev);
 	}
-
-	return 0;
 }
 
 static ssize_t devspec_show(struct device *dev,

drivers/acpi/bus.c

@@ -1019,7 +1019,7 @@ static int acpi_device_probe(struct device *dev)
 	return 0;
 }
 
-static int acpi_device_remove(struct device *dev)
+static void acpi_device_remove(struct device *dev)
 {
 	struct acpi_device *acpi_dev = to_acpi_device(dev);
 	struct acpi_driver *acpi_drv = acpi_dev->driver;
@@ -1034,7 +1034,6 @@ static int acpi_device_remove(struct device *dev)
 	acpi_dev->driver_data = NULL;
 
 	put_device(dev);
-	return 0;
 }
 
 struct bus_type acpi_bus_type = {

drivers/amba/bus.c

@@ -219,7 +219,7 @@ static int amba_probe(struct device *dev)
 	return ret;
 }
 
-static int amba_remove(struct device *dev)
+static void amba_remove(struct device *dev)
 {
 	struct amba_device *pcdev = to_amba_device(dev);
 	struct amba_driver *drv = to_amba_driver(dev->driver);
@@ -236,8 +236,6 @@ static int amba_remove(struct device *dev)
 
 	amba_put_disable_pclk(pcdev);
 	dev_pm_domain_detach(dev, true);
-
-	return 0;
 }
 
 static void amba_shutdown(struct device *dev)

drivers/base/auxiliary.c

@@ -79,7 +79,7 @@ static int auxiliary_bus_probe(struct device *dev)
 	return ret;
 }
 
-static int auxiliary_bus_remove(struct device *dev)
+static void auxiliary_bus_remove(struct device *dev)
 {
 	struct auxiliary_driver *auxdrv = to_auxiliary_drv(dev->driver);
 	struct auxiliary_device *auxdev = to_auxiliary_dev(dev);
@@ -87,8 +87,6 @@ static int auxiliary_bus_remove(struct device *dev)
 	if (auxdrv->remove)
 		auxdrv->remove(auxdev);
 	dev_pm_domain_detach(dev, true);
-
-	return 0;
 }
 
 static void auxiliary_bus_shutdown(struct device *dev)

drivers/base/isa.c

@@ -46,14 +46,12 @@ static int isa_bus_probe(struct device *dev)
 	return 0;
 }
 
-static int isa_bus_remove(struct device *dev)
+static void isa_bus_remove(struct device *dev)
 {
 	struct isa_driver *isa_driver = dev->platform_data;
 
 	if (isa_driver && isa_driver->remove)
 		isa_driver->remove(dev, to_isa_dev(dev)->id);
-
-	return 0;
 }
 
 static void isa_bus_shutdown(struct device *dev)

drivers/base/platform.c

@@ -1438,7 +1438,7 @@ out:
 	return ret;
 }
 
-static int platform_remove(struct device *_dev)
+static void platform_remove(struct device *_dev)
 {
 	struct platform_driver *drv = to_platform_driver(_dev->driver);
 	struct platform_device *dev = to_platform_device(_dev);
@@ -1450,8 +1450,6 @@ static int platform_remove(struct device *_dev)
 			dev_warn(_dev, "remove callback returned a non-zero value. This will be ignored.\n");
 	}
 	dev_pm_domain_detach(_dev, true);
-
-	return 0;
 }
 
 static void platform_shutdown(struct device *_dev)

drivers/bcma/main.c

@@ -27,7 +27,7 @@ static DEFINE_MUTEX(bcma_buses_mutex);
 
 static int bcma_bus_match(struct device *dev, struct device_driver *drv);
 static int bcma_device_probe(struct device *dev);
-static int bcma_device_remove(struct device *dev);
+static void bcma_device_remove(struct device *dev);
 static int bcma_device_uevent(struct device *dev, struct kobj_uevent_env *env);
 
 static ssize_t manuf_show(struct device *dev, struct device_attribute *attr, char *buf)
@@ -614,7 +614,7 @@ static int bcma_device_probe(struct device *dev)
 	return err;
 }
 
-static int bcma_device_remove(struct device *dev)
+static void bcma_device_remove(struct device *dev)
 {
 	struct bcma_device *core = container_of(dev, struct bcma_device, dev);
 	struct bcma_driver *adrv = container_of(dev->driver, struct bcma_driver,
@@ -623,8 +623,6 @@ static int bcma_device_remove(struct device *dev)
 	if (adrv->remove)
 		adrv->remove(core);
 	put_device(dev);
-
-	return 0;
 }
 
 static int bcma_device_uevent(struct device *dev, struct kobj_uevent_env *env)

drivers/bus/sunxi-rsb.c

@@ -169,13 +169,11 @@ static int sunxi_rsb_device_probe(struct device *dev)
 	return drv->probe(rdev);
 }
 
-static int sunxi_rsb_device_remove(struct device *dev)
+static void sunxi_rsb_device_remove(struct device *dev)
 {
 	const struct sunxi_rsb_driver *drv = to_sunxi_rsb_driver(dev->driver);
 
 	drv->remove(to_sunxi_rsb_device(dev));
-
-	return 0;
 }
 
 static struct bus_type sunxi_rsb_bus = {

drivers/cxl/core.c

@@ -1034,13 +1034,12 @@ static int cxl_bus_probe(struct device *dev)
 	return to_cxl_drv(dev->driver)->probe(dev);
 }
 
-static int cxl_bus_remove(struct device *dev)
+static void cxl_bus_remove(struct device *dev)
 {
 	struct cxl_driver *cxl_drv = to_cxl_drv(dev->driver);
 
 	if (cxl_drv->remove)
 		cxl_drv->remove(dev);
-	return 0;
 }
 
 struct bus_type cxl_bus_type = {

drivers/dax/bus.c

@@ -172,15 +172,13 @@ static int dax_bus_probe(struct device *dev)
 	return 0;
 }
 
-static int dax_bus_remove(struct device *dev)
+static void dax_bus_remove(struct device *dev)
 {
 	struct dax_device_driver *dax_drv = to_dax_drv(dev->driver);
 	struct dev_dax *dev_dax = to_dev_dax(dev);
 
 	if (dax_drv->remove)
 		dax_drv->remove(dev_dax);
-
-	return 0;
 }
 
 static struct bus_type dax_bus_type = {

drivers/dma/idxd/sysfs.c

@@ -260,7 +260,7 @@ static void disable_wq(struct idxd_wq *wq)
 	dev_info(dev, "wq %s disabled\n", dev_name(&wq->conf_dev));
 }
 
-static int idxd_config_bus_remove(struct device *dev)
+static void idxd_config_bus_remove(struct device *dev)
 {
 	int rc;
 
@@ -305,8 +305,6 @@ static int idxd_config_bus_remove(struct device *dev)
 			dev_info(dev, "Device %s disabled\n", dev_name(dev));
 
 	}
-
-	return 0;
 }
 
 static void idxd_config_bus_shutdown(struct device *dev)

drivers/firewire/core-device.c

@@ -187,14 +187,12 @@ static int fw_unit_probe(struct device *dev)
 	return driver->probe(fw_unit(dev), unit_match(dev, dev->driver));
 }
 
-static int fw_unit_remove(struct device *dev)
+static void fw_unit_remove(struct device *dev)
 {
 	struct fw_driver *driver =
 			container_of(dev->driver, struct fw_driver, driver);
 
 	driver->remove(fw_unit(dev));
-
-	return 0;
 }
 
 static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)