Patchwork [1/2] hpt366: add debounce delay to cable_detect() method

login
register
mail settings
Submitter Sergei Shtylyov
Date Sept. 27, 2010, 2:08 p.m.
Message ID <201009271808.15710.sshtylyov@ru.mvista.com>
Download mbox | patch
Permalink /patch/65869/
State Accepted
Delegated to: David Miller
Headers show

Comments

Sergei Shtylyov - Sept. 27, 2010, 2:08 p.m.
Alan Cox reported that cable detection sometimes works unreliably
for HPT3xxN and that the issue is fixed by adding debounce delay
as used by the vendor drivers.

While at it, get rid of unneeded parens/space in the vicinity...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: stable@kernel.org

---
The patcn is atop of ide-2.6.git tree...

 drivers/ide/hpt366.c |   12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

--
To unsubscribe from this list: send the line "unsubscribe linux-ide" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
David Miller - Sept. 27, 2010, 6 p.m.
From: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Date: Mon, 27 Sep 2010 18:08:15 +0400

> Alan Cox reported that cable detection sometimes works unreliably
> for HPT3xxN and that the issue is fixed by adding debounce delay
> as used by the vendor drivers.
> 
> While at it, get rid of unneeded parens/space in the vicinity...
> 
> Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>

Applied.
--
To unsubscribe from this list: send the line "unsubscribe linux-ide" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Patch

Index: ide-2.6/drivers/ide/hpt366.c
===================================================================
--- ide-2.6.orig/drivers/ide/hpt366.c
+++ ide-2.6/drivers/ide/hpt366.c
@@ -1173,8 +1173,9 @@  static u8 hpt3xx_cable_detect(ide_hwif_t
 		u16 mcr;
 
 		pci_read_config_word(dev, mcr_addr, &mcr);
-		pci_write_config_word(dev, mcr_addr, (mcr | 0x8000));
-		/* now read cable id register */
+		pci_write_config_word(dev, mcr_addr, mcr | 0x8000);
+		/* Debounce, then read cable ID register */
+		udelay(10);
 		pci_read_config_byte(dev, 0x5a, &scr1);
 		pci_write_config_word(dev, mcr_addr, mcr);
 	} else if (chip_type >= HPT370) {
@@ -1185,10 +1186,11 @@  static u8 hpt3xx_cable_detect(ide_hwif_t
 		u8 scr2 = 0;
 
 		pci_read_config_byte(dev, 0x5b, &scr2);
-		pci_write_config_byte(dev, 0x5b, (scr2 & ~1));
-		/* now read cable id register */
+		pci_write_config_byte(dev, 0x5b, scr2 & ~1);
+		/* Debounce, then read cable ID register */
+		udelay(10);
 		pci_read_config_byte(dev, 0x5a, &scr1);
-		pci_write_config_byte(dev, 0x5b,  scr2);
+		pci_write_config_byte(dev, 0x5b, scr2);
 	} else
 		pci_read_config_byte(dev, 0x5a, &scr1);