linux/drivers/mcb/mcb-pci.c
Dan Carpenter d86fb45b5c mcb: request_mem_region() returns NULL on error
The code here is checking for IS_ERR() when request_mem_region() only
returns NULL on error and never an ERR_PTR.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-04-03 16:15:30 +02:00

138 lines
3 KiB
C

/*
* MEN Chameleon Bus.
*
* Copyright (C) 2014 MEN Mikroelektronik GmbH (www.men.de)
* Author: Johannes Thumshirn <johannes.thumshirn@men.de>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; version 2 of the License.
*/
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/mcb.h>
#include "mcb-internal.h"
struct priv {
struct mcb_bus *bus;
phys_addr_t mapbase;
void __iomem *base;
};
static int mcb_pci_get_irq(struct mcb_device *mdev)
{
struct mcb_bus *mbus = mdev->bus;
struct device *dev = mbus->carrier;
struct pci_dev *pdev = to_pci_dev(dev);
return pdev->irq;
}
static int mcb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
struct resource *res;
struct priv *priv;
int ret;
int num_cells;
unsigned long flags;
priv = devm_kzalloc(&pdev->dev, sizeof(struct priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
ret = pci_enable_device(pdev);
if (ret) {
dev_err(&pdev->dev, "Failed to enable PCI device\n");
return -ENODEV;
}
priv->mapbase = pci_resource_start(pdev, 0);
if (!priv->mapbase) {
dev_err(&pdev->dev, "No PCI resource\n");
goto out_disable;
}
res = request_mem_region(priv->mapbase, CHAM_HEADER_SIZE,
KBUILD_MODNAME);
if (!res) {
dev_err(&pdev->dev, "Failed to request PCI memory\n");
ret = -EBUSY;
goto out_disable;
}
priv->base = ioremap(priv->mapbase, CHAM_HEADER_SIZE);
if (!priv->base) {
dev_err(&pdev->dev, "Cannot ioremap\n");
ret = -ENOMEM;
goto out_release;
}
flags = pci_resource_flags(pdev, 0);
if (flags & IORESOURCE_IO) {
ret = -ENOTSUPP;
dev_err(&pdev->dev,
"IO mapped PCI devices are not supported\n");
goto out_release;
}
pci_set_drvdata(pdev, priv);
priv->bus = mcb_alloc_bus(&pdev->dev);
if (IS_ERR(priv->bus)) {
ret = PTR_ERR(priv->bus);
goto out_iounmap;
}
priv->bus->get_irq = mcb_pci_get_irq;
ret = chameleon_parse_cells(priv->bus, priv->mapbase, priv->base);
if (ret < 0)
goto out_iounmap;
num_cells = ret;
dev_dbg(&pdev->dev, "Found %d cells\n", num_cells);
mcb_bus_add_devices(priv->bus);
return 0;
out_iounmap:
iounmap(priv->base);
out_release:
pci_release_region(pdev, 0);
out_disable:
pci_disable_device(pdev);
return ret;
}
static void mcb_pci_remove(struct pci_dev *pdev)
{
struct priv *priv = pci_get_drvdata(pdev);
mcb_release_bus(priv->bus);
iounmap(priv->base);
release_region(priv->mapbase, CHAM_HEADER_SIZE);
pci_disable_device(pdev);
}
static const struct pci_device_id mcb_pci_tbl[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_MEN, PCI_DEVICE_ID_MEN_CHAMELEON) },
{ 0 },
};
MODULE_DEVICE_TABLE(pci, mcb_pci_tbl);
static struct pci_driver mcb_pci_driver = {
.name = "mcb-pci",
.id_table = mcb_pci_tbl,
.probe = mcb_pci_probe,
.remove = mcb_pci_remove,
};
module_pci_driver(mcb_pci_driver);
MODULE_AUTHOR("Johannes Thumshirn <johannes.thumshirn@men.de>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MCB over PCI support");