[PATCH] ide: fix HPT3xx hotswap support

Fix the broken hotswap code: on HPT37x it caused RESET- to glitch when
tristating the bus (the MISC control 3/6 and soft control 2 need to be written
to in the certain order), and for HPT36x the obsolete HDIO_TRISTATE_HWIF
ioctl() handler was called instead which treated the state argument wrong.
Also, get rid of the soft control reg.  1 wtite to enable IDE interrupt --
this is done in init_hpt37x() already...

Have been tested on HPT370 and 371N.

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 36 insertions, 79 deletions

diff --git a/drivers/ide/pci/hpt366.c b/drivers/ide/pci/hpt366.c
index 787efd35db2b..29a377044323 100644
--- a/drivers/ide/pci/hpt366.c
+++ b/drivers/ide/pci/hpt366.c
@@ -70,6 +70,8 @@
  * - fix/remove bad/unused timing tables and use one set of tables for the whole
  *   HPT37x chip family; save space by introducing the separate transfer mode
  *   table in which the mode lookup is done
+ * - fix the hotswap code:  it caused RESET- to glitch when tristating the bus,
+ *   and for HPT36x the obsolete HDIO_TRISTATE_HWIF handler was called instead
  *              <source@mvista.com>
  *
  */
@@ -914,101 +916,68 @@ static void hpt3xxn_rw_disk(ide_drive_t *drive, struct request *rq)
         hpt3xxn_set_clock(hwif, wantclock);
 }
 
-/*
- * Since SUN Cobalt is attempting to do this operation, I should disclose
- * this has been a long time ago Thu Jul 27 16:40:57 2000 was the patch date
- * HOTSWAP ATA Infrastructure.
- */
-
-static void hpt3xx_reset (ide_drive_t *drive)
-{
-}
-
-static int hpt3xx_tristate (ide_drive_t * drive, int state)
-{
-        ide_hwif_t *hwif        = HWIF(drive);
-        struct pci_dev *dev     = hwif->pci_dev;
-        u8 reg59h = 0, reset    = (hwif->channel) ? 0x80 : 0x40;
-        u8 regXXh = 0, state_reg= (hwif->channel) ? 0x57 : 0x53;
-
-        pci_read_config_byte(dev, 0x59, &reg59h);
-        pci_read_config_byte(dev, state_reg, &regXXh);
-
-        if (state) {
-                (void) ide_do_reset(drive);
-                pci_write_config_byte(dev, state_reg, regXXh|0x80);
-                pci_write_config_byte(dev, 0x59, reg59h|reset);
-        } else {
-                pci_write_config_byte(dev, 0x59, reg59h & ~(reset));
-                pci_write_config_byte(dev, state_reg, regXXh & ~(0x80));
-                (void) ide_do_reset(drive);
-        }
-        return 0;
-}
-
 /* 
- * set/get power state for a drive.
- * turning the power off does the following things:
- *   1) soft-reset the drive
- *   2) tri-states the ide bus
+ * Set/get power state for a drive.
  *
- * when we turn things back on, we need to re-initialize things.
+ * When we turn the power back on, we need to re-initialize things.
  */
 #define TRISTATE_BIT  0x8000
-static int hpt370_busproc(ide_drive_t * drive, int state)
+
+static int hpt3xx_busproc(ide_drive_t *drive, int state)
 {
         ide_hwif_t *hwif        = drive->hwif;
         struct pci_dev *dev     = hwif->pci_dev;
-        u8 tristate = 0, resetmask = 0, bus_reg = 0;
-        u16 tri_reg;
+        u8  tristate, resetmask, bus_reg = 0;
+        u16 tri_reg = 0;
 
         hwif->bus_state = state;
 
         if (hwif->channel) { 
                 /* secondary channel */
-                tristate = 0x56;
-                resetmask = 0x80; 
+                tristate  = 0x56;
+                resetmask = 0x80;
         } else { 
                 /* primary channel */
-                tristate = 0x52;
+                tristate  = 0x52;
                 resetmask = 0x40;
         }
 
-        /* grab status */
+        /* Grab the status. */
         pci_read_config_word(dev, tristate, &tri_reg);
         pci_read_config_byte(dev, 0x59, &bus_reg);
 
-        /* set the state. we don't set it if we don't need to do so.
-         * make sure that the drive knows that it has failed if it's off */
+        /*
+         * Set the state. We don't set it if we don't need to do so.
+         * Make sure that the drive knows that it has failed if it's off.
+         */
         switch (state) {
         case BUSSTATE_ON:
-                hwif->drives[0].failures = 0;
-                hwif->drives[1].failures = 0;
-                if ((bus_reg & resetmask) == 0)
+                if (!(bus_reg & resetmask))
                         return 0;
-                tri_reg &= ~TRISTATE_BIT;
-                bus_reg &= ~resetmask;
-                break;
+                hwif->drives[0].failures = hwif->drives[1].failures = 0;
+
+                pci_write_config_byte(dev, 0x59, bus_reg & ~resetmask);
+                pci_write_config_word(dev, tristate, tri_reg & ~TRISTATE_BIT);
+                return 0;
         case BUSSTATE_OFF:
-                hwif->drives[0].failures = hwif->drives[0].max_failures + 1;
-                hwif->drives[1].failures = hwif->drives[1].max_failures + 1;
-                if ((tri_reg & TRISTATE_BIT) == 0 && (bus_reg & resetmask))
+                if ((bus_reg & resetmask) && !(tri_reg & TRISTATE_BIT))
                         return 0;
                 tri_reg &= ~TRISTATE_BIT;
-                bus_reg |= resetmask;
                 break;
         case BUSSTATE_TRISTATE:
-                hwif->drives[0].failures = hwif->drives[0].max_failures + 1;
-                hwif->drives[1].failures = hwif->drives[1].max_failures + 1;
-                if ((tri_reg & TRISTATE_BIT) && (bus_reg & resetmask))
+                if ((bus_reg & resetmask) &&  (tri_reg & TRISTATE_BIT))
                         return 0;
                 tri_reg |= TRISTATE_BIT;
-                bus_reg |= resetmask;
                 break;
+        default:
+                return -EINVAL;
         }
-        pci_write_config_byte(dev, 0x59, bus_reg);
-        pci_write_config_word(dev, tristate, tri_reg);
 
+        hwif->drives[0].failures = hwif->drives[0].max_failures + 1;
+        hwif->drives[1].failures = hwif->drives[1].max_failures + 1;
+
+        pci_write_config_word(dev, tristate, tri_reg);
+        pci_write_config_byte(dev, 0x59, bus_reg | resetmask);
         return 0;
 }
 
@@ -1306,23 +1275,11 @@ static void __devinit init_hwif_hpt366(ide_hwif_t *hwif)
         if (serialize && hwif->mate)
                 hwif->serialized = hwif->mate->serialized = 1;
 
-        if (info->revision >= 3) {
-                u8 reg5ah = 0;
-                        pci_write_config_byte(dev, 0x5a, reg5ah & ~0x10);
-                /*
-                 * set up ioctl for power status.
-                 * note: power affects both
-                 * drives on each channel
-                 */
-                hwif->resetproc = &hpt3xx_reset;
-                hwif->busproc   = &hpt370_busproc;
-        } else if (info->revision >= 2) {
-                hwif->resetproc = &hpt3xx_reset;
-                hwif->busproc   = &hpt3xx_tristate;
-        } else {
-                hwif->resetproc = &hpt3xx_reset;
-                hwif->busproc   = &hpt3xx_tristate;
-        }
+        /*
+         * Set up ioctl for power status.
+         * NOTE:  power affects both drives on each channel.
+         */
+        hwif->busproc = &hpt3xx_busproc;
 
         if (!hwif->dma_base) {
                 hwif->drives[0].autotune = 1;