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From: Mark Brown <broonie@opensource.wolfsonmicro.com>
To: Samuel Ortiz <sameo@openedhand.com>
Cc: linux-kernel@vger.kernel.org,
	Mark Brown <broonie@opensource.wolfsonmicro.com>
Subject: [PATCH 2/4] mfd: Add some documentation for WM8350 register lock
Date: Thu,  6 Nov 2008 13:43:04 +0000	[thread overview]
Message-ID: <1225978986-25990-2-git-send-email-broonie@opensource.wolfsonmicro.com> (raw)
In-Reply-To: <1225978986-25990-1-git-send-email-broonie@opensource.wolfsonmicro.com>

Hopefully this will make the purpose of these functions a bit clearer,
it's not immediately obvious that the lock is a hardware feature.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
---
 drivers/mfd/wm8350-core.c |   16 ++++++++++++++++
 1 files changed, 16 insertions(+), 0 deletions(-)

diff --git a/drivers/mfd/wm8350-core.c b/drivers/mfd/wm8350-core.c
index 0d47fb9..d63a530 100644
--- a/drivers/mfd/wm8350-core.c
+++ b/drivers/mfd/wm8350-core.c
@@ -299,6 +299,13 @@ int wm8350_block_write(struct wm8350 *wm8350, int start_reg, int regs,
 }
 EXPORT_SYMBOL_GPL(wm8350_block_write);
 
+/**
+ * wm8350_reg_lock()
+ *
+ * The WM8350 has a hardware lock which can be used to prevent writes to
+ * some registers (generally those which can cause particularly serious
+ * problems if misused).  This function enables that lock.
+ */
 int wm8350_reg_lock(struct wm8350 *wm8350)
 {
 	u16 key = WM8350_LOCK_KEY;
@@ -314,6 +321,15 @@ int wm8350_reg_lock(struct wm8350 *wm8350)
 }
 EXPORT_SYMBOL_GPL(wm8350_reg_lock);
 
+/**
+ * wm8350_reg_unlock()
+ *
+ * The WM8350 has a hardware lock which can be used to prevent writes to
+ * some registers (generally those which can cause particularly serious
+ * problems if misused).  This function disables that lock so updates
+ * can be performed.  For maximum safety this should be done only when
+ * required.
+ */
 int wm8350_reg_unlock(struct wm8350 *wm8350)
 {
 	u16 key = WM8350_UNLOCK_KEY;
-- 
1.5.6.5


  reply	other threads:[~2008-11-06 13:43 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-11-06 13:42 [PATCH 0/4] mfd: WM8350 updates Mark Brown
2008-11-06 13:43 ` [PATCH 1/4] mfd: Remove i.MX31ism from WM8350 i2c driver Mark Brown
2008-11-06 13:43   ` Mark Brown [this message]
2008-11-06 13:43     ` [PATCH 3/4] mfd: Add WM8350 revision H support Mark Brown
2008-11-06 13:43       ` [PATCH 4/4] mfd: Add AUXADC support for WM8350 Mark Brown
2008-11-08  0:33 ` [PATCH 0/4] mfd: WM8350 updates Samuel Ortiz

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