linux/drivers/firmware/google/coreboot_table.c
Uwe Kleine-König fc7a6209d5 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>
2021-07-21 11:53:42 +02:00

205 lines
4.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* coreboot_table.c
*
* Module providing coreboot table access.
*
* Copyright 2017 Google Inc.
* Copyright 2017 Samuel Holland <samuel@sholland.org>
*/
#include <linux/acpi.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include "coreboot_table.h"
#define CB_DEV(d) container_of(d, struct coreboot_device, dev)
#define CB_DRV(d) container_of(d, struct coreboot_driver, drv)
static int coreboot_bus_match(struct device *dev, struct device_driver *drv)
{
struct coreboot_device *device = CB_DEV(dev);
struct coreboot_driver *driver = CB_DRV(drv);
return device->entry.tag == driver->tag;
}
static int coreboot_bus_probe(struct device *dev)
{
int ret = -ENODEV;
struct coreboot_device *device = CB_DEV(dev);
struct coreboot_driver *driver = CB_DRV(dev->driver);
if (driver->probe)
ret = driver->probe(device);
return ret;
}
static void coreboot_bus_remove(struct device *dev)
{
struct coreboot_device *device = CB_DEV(dev);
struct coreboot_driver *driver = CB_DRV(dev->driver);
if (driver->remove)
driver->remove(device);
}
static struct bus_type coreboot_bus_type = {
.name = "coreboot",
.match = coreboot_bus_match,
.probe = coreboot_bus_probe,
.remove = coreboot_bus_remove,
};
static void coreboot_device_release(struct device *dev)
{
struct coreboot_device *device = CB_DEV(dev);
kfree(device);
}
int coreboot_driver_register(struct coreboot_driver *driver)
{
driver->drv.bus = &coreboot_bus_type;
return driver_register(&driver->drv);
}
EXPORT_SYMBOL(coreboot_driver_register);
void coreboot_driver_unregister(struct coreboot_driver *driver)
{
driver_unregister(&driver->drv);
}
EXPORT_SYMBOL(coreboot_driver_unregister);
static int coreboot_table_populate(struct device *dev, void *ptr)
{
int i, ret;
void *ptr_entry;
struct coreboot_device *device;
struct coreboot_table_entry *entry;
struct coreboot_table_header *header = ptr;
ptr_entry = ptr + header->header_bytes;
for (i = 0; i < header->table_entries; i++) {
entry = ptr_entry;
device = kzalloc(sizeof(struct device) + entry->size, GFP_KERNEL);
if (!device)
return -ENOMEM;
dev_set_name(&device->dev, "coreboot%d", i);
device->dev.parent = dev;
device->dev.bus = &coreboot_bus_type;
device->dev.release = coreboot_device_release;
memcpy(&device->entry, ptr_entry, entry->size);
ret = device_register(&device->dev);
if (ret) {
put_device(&device->dev);
return ret;
}
ptr_entry += entry->size;
}
return 0;
}
static int coreboot_table_probe(struct platform_device *pdev)
{
resource_size_t len;
struct coreboot_table_header *header;
struct resource *res;
struct device *dev = &pdev->dev;
void *ptr;
int ret;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -EINVAL;
len = resource_size(res);
if (!res->start || !len)
return -EINVAL;
/* Check just the header first to make sure things are sane */
header = memremap(res->start, sizeof(*header), MEMREMAP_WB);
if (!header)
return -ENOMEM;
len = header->header_bytes + header->table_bytes;
ret = strncmp(header->signature, "LBIO", sizeof(header->signature));
memunmap(header);
if (ret) {
dev_warn(dev, "coreboot table missing or corrupt!\n");
return -ENODEV;
}
ptr = memremap(res->start, len, MEMREMAP_WB);
if (!ptr)
return -ENOMEM;
ret = bus_register(&coreboot_bus_type);
if (!ret) {
ret = coreboot_table_populate(dev, ptr);
if (ret)
bus_unregister(&coreboot_bus_type);
}
memunmap(ptr);
return ret;
}
static int __cb_dev_unregister(struct device *dev, void *dummy)
{
device_unregister(dev);
return 0;
}
static int coreboot_table_remove(struct platform_device *pdev)
{
bus_for_each_dev(&coreboot_bus_type, NULL, NULL, __cb_dev_unregister);
bus_unregister(&coreboot_bus_type);
return 0;
}
#ifdef CONFIG_ACPI
static const struct acpi_device_id cros_coreboot_acpi_match[] = {
{ "GOOGCB00", 0 },
{ "BOOT0000", 0 },
{ }
};
MODULE_DEVICE_TABLE(acpi, cros_coreboot_acpi_match);
#endif
#ifdef CONFIG_OF
static const struct of_device_id coreboot_of_match[] = {
{ .compatible = "coreboot" },
{}
};
MODULE_DEVICE_TABLE(of, coreboot_of_match);
#endif
static struct platform_driver coreboot_table_driver = {
.probe = coreboot_table_probe,
.remove = coreboot_table_remove,
.driver = {
.name = "coreboot_table",
.acpi_match_table = ACPI_PTR(cros_coreboot_acpi_match),
.of_match_table = of_match_ptr(coreboot_of_match),
},
};
module_platform_driver(coreboot_table_driver);
MODULE_AUTHOR("Google, Inc.");
MODULE_LICENSE("GPL");