alim15x3: add ali_fifo_control() helper

Based on libata pata_ali host driver.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 15 insertions, 16 deletions

diff --git a/drivers/ide/alim15x3.c b/drivers/ide/alim15x3.c
index 99c355e8785..4b47896df9f 100644
--- a/drivers/ide/alim15x3.c
+++ b/drivers/ide/alim15x3.c
@@ -48,6 +48,19 @@ static u8 m5229_revision;
 static u8 chip_is_1543c_e;
 static struct pci_dev *isa_dev;
 
+static void ali_fifo_control(ide_hwif_t *hwif, ide_drive_t *drive, int on)
+{
+        struct pci_dev *pdev = to_pci_dev(hwif->dev);
+        int pio_fifo = 0x54 + hwif->channel;
+        u8 fifo;
+        int shift = 4 * (drive->dn & 1);
+
+        pci_read_config_byte(pdev, pio_fifo, &fifo);
+        fifo &= ~(0x0F << shift);
+        fifo |= (on << shift);
+        pci_write_config_byte(pdev, pio_fifo, fifo);
+}
+
 /**
  *      ali_set_pio_mode        -       set host controller for PIO mode
  *      @drive: drive
@@ -64,8 +77,7 @@ static void ali_set_pio_mode(ide_drive_t *drive, const u8 pio)
         int bus_speed = ide_pci_clk ? ide_pci_clk : 33;
         unsigned long T =  1000000 / bus_speed; /* PCI clock based */
         int port = hwif->channel ? 0x5c : 0x58;
-        int portFIFO = hwif->channel ? 0x55 : 0x54;
-        u8 cd_dma_fifo = 0, unit = drive->dn & 1;
+        u8 unit = drive->dn & 1;
         struct ide_timing t;
 
         ide_timing_compute(drive, XFER_PIO_0 + pio, &t, T, 1);
@@ -79,20 +91,7 @@ static void ali_set_pio_mode(ide_drive_t *drive, const u8 pio)
         /* 
          * PIO mode => ATA FIFO on, ATAPI FIFO off
          */
-        pci_read_config_byte(dev, portFIFO, &cd_dma_fifo);
-        if (drive->media==ide_disk) {
-                if (unit) {
-                        pci_write_config_byte(dev, portFIFO, (cd_dma_fifo & 0x0F) | 0x50);
-                } else {
-                        pci_write_config_byte(dev, portFIFO, (cd_dma_fifo & 0xF0) | 0x05);
-                }
-        } else {
-                if (unit) {
-                        pci_write_config_byte(dev, portFIFO, cd_dma_fifo & 0x0F);
-                } else {
-                        pci_write_config_byte(dev, portFIFO, cd_dma_fifo & 0xF0);
-                }
-        }
+        ali_fifo_control(hwif, drive, (drive->media == ide_disk) ? 0x05 : 0x00);
 
         pci_write_config_byte(dev, port, t.setup);
         pci_write_config_byte(dev, port + unit + 2,