android_kernel_motorola_sm6225/drivers/ide/cs5530.c
Julia Lawall 9ecab6e5bf drivers/ide/{cs5530.c,sc1200.c}: Move a dereference below a NULL test
In each case, if the NULL test is necessary, then the dereference should be
moved below the NULL test.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
type T;
expression E;
identifier i,fld;
statement S;
@@

- T i = E->fld;
+ T i;
  ... when != E
      when != i
  if (E == NULL) S
+ i = E->fld;
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2008-12-22 23:05:06 +01:00

295 lines
8.2 KiB
C

/*
* Copyright (C) 2000 Andre Hedrick <andre@linux-ide.org>
* Copyright (C) 2000 Mark Lord <mlord@pobox.com>
* Copyright (C) 2007 Bartlomiej Zolnierkiewicz
*
* May be copied or modified under the terms of the GNU General Public License
*
* Development of this chipset driver was funded
* by the nice folks at National Semiconductor.
*
* Documentation:
* CS5530 documentation available from National Semiconductor.
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/ide.h>
#include <asm/io.h>
#define DRV_NAME "cs5530"
/*
* Here are the standard PIO mode 0-4 timings for each "format".
* Format-0 uses fast data reg timings, with slower command reg timings.
* Format-1 uses fast timings for all registers, but won't work with all drives.
*/
static unsigned int cs5530_pio_timings[2][5] = {
{0x00009172, 0x00012171, 0x00020080, 0x00032010, 0x00040010},
{0xd1329172, 0x71212171, 0x30200080, 0x20102010, 0x00100010}
};
/*
* After chip reset, the PIO timings are set to 0x0000e132, which is not valid.
*/
#define CS5530_BAD_PIO(timings) (((timings)&~0x80000000)==0x0000e132)
#define CS5530_BASEREG(hwif) (((hwif)->dma_base & ~0xf) + ((hwif)->channel ? 0x30 : 0x20))
/**
* cs5530_set_pio_mode - set host controller for PIO mode
* @drive: drive
* @pio: PIO mode number
*
* Handles setting of PIO mode for the chipset.
*
* The init_hwif_cs5530() routine guarantees that all drives
* will have valid default PIO timings set up before we get here.
*/
static void cs5530_set_pio_mode(ide_drive_t *drive, const u8 pio)
{
unsigned long basereg = CS5530_BASEREG(drive->hwif);
unsigned int format = (inl(basereg + 4) >> 31) & 1;
outl(cs5530_pio_timings[format][pio], basereg + ((drive->dn & 1)<<3));
}
/**
* cs5530_udma_filter - UDMA filter
* @drive: drive
*
* cs5530_udma_filter() does UDMA mask filtering for the given drive
* taking into the consideration capabilities of the mate device.
*
* The CS5530 specifies that two drives sharing a cable cannot mix
* UDMA/MDMA. It has to be one or the other, for the pair, though
* different timings can still be chosen for each drive. We could
* set the appropriate timing bits on the fly, but that might be
* a bit confusing. So, for now we statically handle this requirement
* by looking at our mate drive to see what it is capable of, before
* choosing a mode for our own drive.
*
* Note: This relies on the fact we never fail from UDMA to MWDMA2
* but instead drop to PIO.
*/
static u8 cs5530_udma_filter(ide_drive_t *drive)
{
ide_hwif_t *hwif = drive->hwif;
ide_drive_t *mate = ide_get_pair_dev(drive);
u16 *mateid;
u8 mask = hwif->ultra_mask;
if (mate == NULL)
goto out;
mateid = mate->id;
if (ata_id_has_dma(mateid) && __ide_dma_bad_drive(mate) == 0) {
if ((mateid[ATA_ID_FIELD_VALID] & 4) &&
(mateid[ATA_ID_UDMA_MODES] & 7))
goto out;
if ((mateid[ATA_ID_FIELD_VALID] & 2) &&
(mateid[ATA_ID_MWDMA_MODES] & 7))
mask = 0;
}
out:
return mask;
}
static void cs5530_set_dma_mode(ide_drive_t *drive, const u8 mode)
{
unsigned long basereg;
unsigned int reg, timings = 0;
switch (mode) {
case XFER_UDMA_0: timings = 0x00921250; break;
case XFER_UDMA_1: timings = 0x00911140; break;
case XFER_UDMA_2: timings = 0x00911030; break;
case XFER_MW_DMA_0: timings = 0x00077771; break;
case XFER_MW_DMA_1: timings = 0x00012121; break;
case XFER_MW_DMA_2: timings = 0x00002020; break;
}
basereg = CS5530_BASEREG(drive->hwif);
reg = inl(basereg + 4); /* get drive0 config register */
timings |= reg & 0x80000000; /* preserve PIO format bit */
if ((drive-> dn & 1) == 0) { /* are we configuring drive0? */
outl(timings, basereg + 4); /* write drive0 config register */
} else {
if (timings & 0x00100000)
reg |= 0x00100000; /* enable UDMA timings for both drives */
else
reg &= ~0x00100000; /* disable UDMA timings for both drives */
outl(reg, basereg + 4); /* write drive0 config register */
outl(timings, basereg + 12); /* write drive1 config register */
}
}
/**
* init_chipset_5530 - set up 5530 bridge
* @dev: PCI device
*
* Initialize the cs5530 bridge for reliable IDE DMA operation.
*/
static unsigned int init_chipset_cs5530(struct pci_dev *dev)
{
struct pci_dev *master_0 = NULL, *cs5530_0 = NULL;
if (pci_resource_start(dev, 4) == 0)
return -EFAULT;
dev = NULL;
while ((dev = pci_get_device(PCI_VENDOR_ID_CYRIX, PCI_ANY_ID, dev)) != NULL) {
switch (dev->device) {
case PCI_DEVICE_ID_CYRIX_PCI_MASTER:
master_0 = pci_dev_get(dev);
break;
case PCI_DEVICE_ID_CYRIX_5530_LEGACY:
cs5530_0 = pci_dev_get(dev);
break;
}
}
if (!master_0) {
printk(KERN_ERR DRV_NAME ": unable to locate PCI MASTER function\n");
goto out;
}
if (!cs5530_0) {
printk(KERN_ERR DRV_NAME ": unable to locate CS5530 LEGACY function\n");
goto out;
}
/*
* Enable BusMaster and MemoryWriteAndInvalidate for the cs5530:
* --> OR 0x14 into 16-bit PCI COMMAND reg of function 0 of the cs5530
*/
pci_set_master(cs5530_0);
pci_try_set_mwi(cs5530_0);
/*
* Set PCI CacheLineSize to 16-bytes:
* --> Write 0x04 into 8-bit PCI CACHELINESIZE reg of function 0 of the cs5530
*/
pci_write_config_byte(cs5530_0, PCI_CACHE_LINE_SIZE, 0x04);
/*
* Disable trapping of UDMA register accesses (Win98 hack):
* --> Write 0x5006 into 16-bit reg at offset 0xd0 of function 0 of the cs5530
*/
pci_write_config_word(cs5530_0, 0xd0, 0x5006);
/*
* Bit-1 at 0x40 enables MemoryWriteAndInvalidate on internal X-bus:
* The other settings are what is necessary to get the register
* into a sane state for IDE DMA operation.
*/
pci_write_config_byte(master_0, 0x40, 0x1e);
/*
* Set max PCI burst size (16-bytes seems to work best):
* 16bytes: set bit-1 at 0x41 (reg value of 0x16)
* all others: clear bit-1 at 0x41, and do:
* 128bytes: OR 0x00 at 0x41
* 256bytes: OR 0x04 at 0x41
* 512bytes: OR 0x08 at 0x41
* 1024bytes: OR 0x0c at 0x41
*/
pci_write_config_byte(master_0, 0x41, 0x14);
/*
* These settings are necessary to get the chip
* into a sane state for IDE DMA operation.
*/
pci_write_config_byte(master_0, 0x42, 0x00);
pci_write_config_byte(master_0, 0x43, 0xc1);
out:
pci_dev_put(master_0);
pci_dev_put(cs5530_0);
return 0;
}
/**
* init_hwif_cs5530 - initialise an IDE channel
* @hwif: IDE to initialize
*
* This gets invoked by the IDE driver once for each channel. It
* performs channel-specific pre-initialization before drive probing.
*/
static void __devinit init_hwif_cs5530 (ide_hwif_t *hwif)
{
unsigned long basereg;
u32 d0_timings;
basereg = CS5530_BASEREG(hwif);
d0_timings = inl(basereg + 0);
if (CS5530_BAD_PIO(d0_timings))
outl(cs5530_pio_timings[(d0_timings >> 31) & 1][0], basereg + 0);
if (CS5530_BAD_PIO(inl(basereg + 8)))
outl(cs5530_pio_timings[(d0_timings >> 31) & 1][0], basereg + 8);
}
static const struct ide_port_ops cs5530_port_ops = {
.set_pio_mode = cs5530_set_pio_mode,
.set_dma_mode = cs5530_set_dma_mode,
.udma_filter = cs5530_udma_filter,
};
static const struct ide_port_info cs5530_chipset __devinitdata = {
.name = DRV_NAME,
.init_chipset = init_chipset_cs5530,
.init_hwif = init_hwif_cs5530,
.port_ops = &cs5530_port_ops,
.host_flags = IDE_HFLAG_SERIALIZE |
IDE_HFLAG_POST_SET_MODE,
.pio_mask = ATA_PIO4,
.mwdma_mask = ATA_MWDMA2,
.udma_mask = ATA_UDMA2,
};
static int __devinit cs5530_init_one(struct pci_dev *dev, const struct pci_device_id *id)
{
return ide_pci_init_one(dev, &cs5530_chipset, NULL);
}
static const struct pci_device_id cs5530_pci_tbl[] = {
{ PCI_VDEVICE(CYRIX, PCI_DEVICE_ID_CYRIX_5530_IDE), 0 },
{ 0, },
};
MODULE_DEVICE_TABLE(pci, cs5530_pci_tbl);
static struct pci_driver cs5530_pci_driver = {
.name = "CS5530 IDE",
.id_table = cs5530_pci_tbl,
.probe = cs5530_init_one,
.remove = ide_pci_remove,
.suspend = ide_pci_suspend,
.resume = ide_pci_resume,
};
static int __init cs5530_ide_init(void)
{
return ide_pci_register_driver(&cs5530_pci_driver);
}
static void __exit cs5530_ide_exit(void)
{
pci_unregister_driver(&cs5530_pci_driver);
}
module_init(cs5530_ide_init);
module_exit(cs5530_ide_exit);
MODULE_AUTHOR("Mark Lord");
MODULE_DESCRIPTION("PCI driver module for Cyrix/NS 5530 IDE");
MODULE_LICENSE("GPL");