Hello.
Kukjin Kim wrote:
From: Abhilash Kesavan <a.kesavan@xxxxxxxxxxx>
Adds support for the Samsung PATA controller. This driver is based on the
Libata subsystem and references the earlier patches sent for IDE subsystem.
Signed-off-by: Abhilash Kesavan <a.kesavan@xxxxxxxxxxx>
Signed-off-by: Kukjin Kim <kgene.kim@xxxxxxxxxxx>
[...]
diff --git a/drivers/ata/pata_samsung_cf.c b/drivers/ata/pata_samsung_cf.c
new file mode 100644
index 0000000..aeb2825
--- /dev/null
+++ b/drivers/ata/pata_samsung_cf.c
@@ -0,0 +1,735 @@
[...]
+static unsigned long
+pata_s3c_setup_timing(struct s3c_ide_info *info, const struct ata_timing *ata)
+{
+ int t1;
+ int t2;
+ int t2i;
+ ulong piotime;
+
+ t1 = ata->setup;
+ t2 = ata->act8b;
+ t2i = ata->rec8b;
Could be initializers...
[...]
+/*
+ * pata_s3c_data_xfer - Transfer data by PIO
+ */
+unsigned int pata_s3c_data_xfer(struct ata_device *dev, unsigned char *buf,
+ unsigned int buflen, int rw)
+{
+ struct ata_port *ap = dev->link->ap;
+ struct s3c_ide_info *info = ap->host->private_data;
+ void __iomem *data_addr = ap->ioaddr.data_addr;
+ unsigned int words = buflen >> 1, i;
+ u16 *data_ptr = (u16 *)buf;
+
+ /* Requires wait same as in ata_inb/ata_outb */
+ if (rw == READ)
+ for (i = 0; i < words; i++, data_ptr++) {
+ wait_for_host_ready(info);
+ (void) readw(data_addr);
+ wait_for_host_ready(info);
+ *data_ptr = readw(info->ide_addr
+ + S3C_ATA_PIO_RDATA);
+ }
+ else
+ for (i = 0; i < words; i++, data_ptr++) {
+ wait_for_host_ready(info);
+ writew(*data_ptr, data_addr);
+ }
+
+ if (buflen & 0x01) {
+ dev_err(ap->dev, "unexpected trailing data\n");
+ return -EINVAL;
This method should return number of bytes consumed, never error...
+ }
+
+ return words << 1;
+}
[...]
+/*
+ * pata_s3c_devchk - PATA device presence detection
+ */
+static unsigned int pata_s3c_devchk(struct ata_port *ap,
+ unsigned int device)
+{
+ struct ata_ioports *ioaddr = &ap->ioaddr;
+ u8 nsect, lbal;
+
+ ap->ops->sff_dev_select(ap, device);
Can call pata_s3c_dev_select() directly...
+/*
+ * pata_s3c_wait_after_reset - wait for devices to become ready after reset
+ */
+static int pata_s3c_wait_after_reset(struct ata_link *link,
+ unsigned int devmask, unsigned long deadline)
+{
+ struct ata_port *ap = link->ap;
+ struct ata_ioports *ioaddr = &ap->ioaddr;
+ unsigned int dev0 = devmask & (1 << 0);
+ unsigned int dev1 = devmask & (1 << 1);
+ int rc, ret = 0;
+
+ msleep(ATA_WAIT_AFTER_RESET);
+
+ /* always check readiness of the master device */
+ rc = ata_sff_wait_ready(link, deadline);
+ if (rc)
+ return rc;
+
+ /* if device 1 was found in ata_devchk, wait for register
+ * access briefly, then wait for BSY to clear.
+ */
+ if (dev1) {
+ int i;
+
+ ap->ops->sff_dev_select(ap, 1);
Ditto.
+
+ for (i = 0; i < 2; i++) {
+ u8 nsect, lbal;
+
+ nsect = ata_inb(ap->host, ioaddr->nsect_addr);
+ lbal = ata_inb(ap->host, ioaddr->lbal_addr);
+ if ((nsect == 1) && (lbal == 1))
+ break;
+ msleep(50); /* give drive a breather */
+ }
+
+ rc = ata_sff_wait_ready(link, deadline);
+ if (rc) {
+ if (rc != -ENODEV)
+ return rc;
+ ret = rc;
+ }
+ }
+
Should have copied the original commant here, cause I dount that this
drive selection trickery is indeed necessary...
+ ap->ops->sff_dev_select(ap, 0);
+ if (dev1)
+ ap->ops->sff_dev_select(ap, 1);
+ if (dev0)
+ ap->ops->sff_dev_select(ap, 0);
Ditto.
+/*
+ * pata_s3c_softreset - reset host port via ATA SRST
+ */
+static int pata_s3c_softreset(struct ata_link *link, unsigned int *classes,
+ unsigned long deadline)
+{
+ struct ata_port *ap = link->ap;
+ unsigned int slave_possible = ap->flags & ATA_FLAG_SLAVE_POSS;
I don't see where you set this flag, hence the check seems useless.
+ unsigned int devmask = 0;
+ int rc;
+ u8 err;
+
+ /* determine if device 0/1 are present */
+ if (pata_s3c_devchk(ap, 0))
+ devmask |= (1 << 0);
+ if (slave_possible && pata_s3c_devchk(ap, 1))
+ devmask |= (1 << 1);
+
+ /* select device 0 again */
+ ap->ops->sff_dev_select(ap, 0);
Can call pata_s3c_dev_select() directly...
+
+ /* issue bus reset */
+ rc = pata_s3c_bus_softreset(ap, devmask, deadline);
+ /* if link is occupied, -ENODEV too is an error */
+ if (rc && (rc != -ENODEV || sata_scr_valid(link))) {
sata_scr_valid() doesn't apply to your PATA driver, no need to call it.
+static void pata_s3c_hwinit(struct s3c_ide_info *info,
+ struct s3c_ide_platdata *pdata)
+{
+ switch (info->cpu_type) {
+ case TYPE_S3C64XX:
+ /* Configure as big endian */
+ pata_s3c_cfg_mode(info->sfr_addr);
+ pata_s3c_set_endian(info->ide_addr, 1);
+ pata_s3c_enable(info->ide_addr, true);
+ msleep(100);
+
+ /* Remove IRQ Status */
+ writel(0x1f, info->ide_addr + S3C_ATA_IRQ);
+ writel(0x1b, info->ide_addr + S3C_ATA_IRQ_MSK);
+ break;
Mis-indented: one more tab needed.
+
+ case TYPE_S5PC100:
+ pata_s3c_cfg_mode(info->sfr_addr);
There should be a comment like /* FALLTHRU */ if *break* is omitted.
+ case TYPE_S5PV210:
+ /* Configure as little endian */
+ pata_s3c_set_endian(info->ide_addr, 0);
+ pata_s3c_enable(info->ide_addr, true);
+ msleep(100);
+
+ /* Remove IRQ Status */
+ writel(0x3f, info->ide_addr + S3C_ATA_IRQ);
+ writel(0x3f, info->ide_addr + S3C_ATA_IRQ_MSK);
+ break;
Mis-indented.
+static int __devinit pata_s3c_probe(struct platform_device *pdev)
Is this device really hot-pluggable? Shouldn't this be '__init' instead?
+{
+ struct s3c_ide_platdata *pdata = pdev->dev.platform_data;
+ struct device *dev = &pdev->dev;
+ struct s3c_ide_info *info;
+ struct resource *res;
+ struct ata_port *ap;
+ struct ata_host *host;
+ enum s3c_cpu_type cpu_type;
+ int ret;
+
+ cpu_type = platform_get_device_id(pdev)->driver_data;
+
+ info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
+ if (!info) {
+ dev_err(dev, "failed to allocate memory for device data\n");
+ return -ENOMEM;
+ }
+
+ info->irq = platform_get_irq(pdev, 0);
+ if (info->irq < 0) {
+ dev_err(dev, "could not obtain irq number\n");
You driver permits working without IRQ -- why require an IRQ resource even
if there's no IRQ?
[...]
+ if (!info->irq) {
Should be (info->irq <= 0) instead, I think, with the above check removed.
+ ap->flags |= ATA_FLAG_PIO_POLLING;
+ ata_port_desc(ap, "no IRQ, using PIO polling\n");
+ }
+
[...]
+static struct platform_driver pata_s3c_driver = {
+ .probe = pata_s3c_probe,
If this function will be '__init', this needs to be removed.
[...]
+static int __init pata_s3c_init(void)
+{
+ return platform_driver_register(&pata_s3c_driver);
I'd coinsider platform_driver_probe() -- this device doesn't seem to be
hot-pluggable...
MBR, Sergei
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