Extend erase timeout in M25P80 SPI Flash driver

svn path=/dists/sid/linux-2.6/; revision=13459

debian/changelog

@@ -1,8 +1,12 @@
 linux-2.6 (2.6.29-4) UNRELEASED; urgency=low
 
+  [ maximilian attems ]
   * drm/i915: allow tiled front buffers on 965+.
   * [parisc] Disable BTRFS.
 
+  [ Martin Michlmayr ]
+  * Extend erase timeout in M25P80 SPI Flash driver (Peter Horton).
+
  -- maximilian attems <maks@debian.org>  Fri, 17 Apr 2009 11:30:55 +0200
 
 linux-2.6 (2.6.29-3) unstable; urgency=low

debian/patches/bugfix/all/extend-erase-timeout-spi-flash.patch

@@ -0,0 +1,54 @@
+Extend erase timeout in M25P80 SPI Flash driver.
+
+The M25P80 drivers fails erasing sectors on a M25P128 because the ready
+wait timeout is too short. Change the timeout from a simple loop count to a
+suitable number of seconds.
+
+Signed-off-by: Peter Horton <zero@colonel-panic.org>
+---
+Index: linux-2.6.29-git12/drivers/mtd/devices/m25p80.c
+===================================================================
+--- linux-2.6.29-git12.orig/drivers/mtd/devices/m25p80.c	2009-04-12 21:41:16.000000000 +0000
++++ linux-2.6.29-git12/drivers/mtd/devices/m25p80.c	2009-04-12 21:43:01.000000000 +0000
+@@ -54,7 +54,7 @@
+ #define	SR_SRWD			0x80	/* SR write protect */
+ 
+ /* Define max times to check status register before we give up. */
+-#define	MAX_READY_WAIT_COUNT	100000
++#define	MAX_READY_WAIT_JIFFIES	(10 * HZ)	/* eg. M25P128 specs 6s max sector erase */
+ #define	CMD_SIZE		4
+ 
+ #ifdef CONFIG_M25PXX_USE_FAST_READ
+@@ -145,20 +145,20 @@
+  */
+ static int wait_till_ready(struct m25p *flash)
+ {
+-	int count;
++	unsigned long deadline;
+ 	int sr;
+ 
+-	/* one chip guarantees max 5 msec wait here after page writes,
+-	 * but potentially three seconds (!) after page erase.
+-	 */
+-	for (count = 0; count < MAX_READY_WAIT_COUNT; count++) {
++	deadline = jiffies + MAX_READY_WAIT_JIFFIES;
++
++	do {
+ 		if ((sr = read_sr(flash)) < 0)
+ 			break;
+ 		else if (!(sr & SR_WIP))
+ 			return 0;
+ 
+-		/* REVISIT sometimes sleeping would be best */
+-	}
++		cond_resched();
++
++	} while (!time_after_eq(jiffies, deadline));
+ 
+ 	return 1;
+ }
+--
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debian/patches/series/4

@@ -1 +1,2 @@
 + bugfix/all/drm-intel.git-f544847fbaf099278343f875987a983f2b913134.patch
++ bugfix/all/extend-erase-timeout-spi-flash.patch