pata_atp867x: clarifications in timings calculations and cable detection

Signed-off-by: John(Jung-Ik) Lee <jilee@google.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

diff --git a/drivers/ata/pata_atp867x.c b/drivers/ata/pata_atp867x.c
index ebfc8ff86519632f2b539230e21d3b7ab5d7693c..27d3148b3d8ecae994196b7bca0cdc67e494158d 100644 (file)
--- a/drivers/ata/pata_atp867x.c
+++ b/drivers/ata/pata_atp867x.c
@@ -149,8 +149,10 @@ static void atp867x_set_dmamode(struct ata_port *ap, struct ata_device *adev)
        iowrite8(b, dp->dma_mode);
 }
 
-static int atp867x_get_active_clocks_shifted(unsigned int clk)
+static int atp867x_get_active_clocks_shifted(struct ata_port *ap,
+       unsigned int clk)
 {
+       struct atp867x_priv *dp = ap->private_data;
        unsigned char clocks = clk;
 
        switch (clocks) {
@@ -159,15 +161,25 @@ static int atp867x_get_active_clocks_shifted(unsigned int clk)
                break;
        case 1 ... 7:
                break;
-       case 8 ... 12:
+       case 9 ... 12:
                clocks = 7;
                break;
        default:
                printk(KERN_WARNING "ATP867X: active %dclk is invalid. "
                        "Using default 8clk.\n", clk);
-               clocks = 0;     /* 8 clk */
-               break;
+       case 8: /* default 8 clk */
+               clocks = 0;
+               goto active_clock_shift_done;
        }
+
+       /*
+        * Doc 6.6.9: increase the clock value by 1 for safer PIO speed
+        * on 66MHz bus
+        */
+       if (dp->pci66mhz && clocks < 7)
+               clocks++;
+
+active_clock_shift_done:
        return clocks << ATP867X_IO_PIOSPD_ACTIVE_SHIFT;
 }
 
@@ -181,20 +193,19 @@ static int atp867x_get_recover_clocks_shifted(unsigned int clk)
                break;
        case 1 ... 11:
                break;
-       case 12:
-               clocks = 0;
-               break;
        case 13: case 14:
-               --clocks;
+               --clocks;       /* by the spec */
                break;
        case 15:
                break;
        default:
                printk(KERN_WARNING "ATP867X: recover %dclk is invalid. "
-                       "Using default 15clk.\n", clk);
-               clocks = 0;     /* 12 clk */
+                       "Using default 12clk.\n", clk);
+       case 12:        /* default 12 clk */
+               clocks = 0;
                break;
        }
+
        return clocks << ATP867X_IO_PIOSPD_RECOVER_SHIFT;
 }
 
@@ -223,10 +234,8 @@ static void atp867x_set_piomode(struct ata_port *ap, struct ata_device *adev)
                b = (b & ~ATP867X_IO_DMAMODE_MSTR_MASK);
        iowrite8(b, dp->dma_mode);
 
-       b = atp867x_get_active_clocks_shifted(t.active) |
+       b = atp867x_get_active_clocks_shifted(ap, t.active) |
                atp867x_get_recover_clocks_shifted(t.recover);
-       if (dp->pci66mhz)
-               b += 0x10;
 
        if (adev->devno & 1)
                iowrite8(b, dp->slave_piospd);
@@ -239,9 +248,24 @@ static void atp867x_set_piomode(struct ata_port *ap, struct ata_device *adev)
        iowrite8(b, dp->eightb_piospd);
 }
 
+static int atp867x_cable_override(struct pci_dev *pdev)
+{
+       if (pdev->subsystem_vendor == PCI_VENDOR_ID_ARTOP &&
+               (pdev->subsystem_device == PCI_DEVICE_ID_ARTOP_ATP867A ||
+                pdev->subsystem_device == PCI_DEVICE_ID_ARTOP_ATP867B)) {
+               return 1;
+       }
+       return 0;
+}
+
 static int atp867x_cable_detect(struct ata_port *ap)
 {
-       return ATA_CBL_PATA40_SHORT;
+       struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+
+       if (atp867x_cable_override(pdev))
+               return ATA_CBL_PATA40_SHORT;
+
+       return ATA_CBL_PATA_UNK;
 }
 
 static struct scsi_host_template atp867x_sht = {