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From: wellsk40-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org
To: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Cc: vitaly.wool-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org,
	Kevin Wells <wellsk40-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Subject: [PATCH 1/3] i2c-pnx: Limit maximum divider to 1023
Date: Tue, 16 Mar 2010 15:55:36 -0700	[thread overview]
Message-ID: <1268780138-10019-3-git-send-email-wellsk40@gmail.com> (raw)
In-Reply-To: <1268780138-10019-1-git-send-email-wellsk40-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>

From: Kevin Wells <wellsk40-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>

Limit maximum divider to 0x3ff to divider computations. On high I2C
parent clock rates, the divider can exceed 0x3ff. This will help
prevent some very odd clock rates.

Signed-off-by: Kevin Wells <wellsk40-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
 drivers/i2c/busses/i2c-pnx.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/i2c/busses/i2c-pnx.c b/drivers/i2c/busses/i2c-pnx.c
index 9532dee..77919fa 100644
--- a/drivers/i2c/busses/i2c-pnx.c
+++ b/drivers/i2c/busses/i2c-pnx.c
@@ -632,6 +632,8 @@ static int __devinit i2c_pnx_probe(struct platform_device *pdev)
 	 */
 
 	tmp = ((freq / 1000) / I2C_PNX_SPEED_KHZ) / 2 - 2;
+	if (tmp > 0x3FF)
+		tmp = 0x3FF;
 	iowrite32(tmp, I2C_REG_CKH(alg_data));
 	iowrite32(tmp, I2C_REG_CKL(alg_data));
 
-- 
1.6.6

  parent reply	other threads:[~2010-03-16 22:55 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-03-16 22:55 i2c-pnx: Improvements and fixes wellsk40-Re5JQEeQqe8AvxtiuMwx3w
     [not found] ` <1268780138-10019-1-git-send-email-wellsk40-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2010-03-16 22:55   ` [PATCH 1/3] i2c-pnx: Limit maximum divider to 1023 wellsk40-Re5JQEeQqe8AvxtiuMwx3w
2010-03-16 22:55   ` wellsk40-Re5JQEeQqe8AvxtiuMwx3w [this message]
2010-03-16 22:55   ` [PATCH 2/3] i2c-pnx: Add stop conditions for end of transfer wellsk40-Re5JQEeQqe8AvxtiuMwx3w
2010-03-16 22:55   ` [PATCH 3/3] i2c-pnx: Disable/enable clocks only when needed to reduce power wellsk40-Re5JQEeQqe8AvxtiuMwx3w
     [not found]     ` <1268780138-10019-5-git-send-email-wellsk40-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2010-04-05 23:01       ` Ben Dooks
2010-03-22 17:09   ` i2c-pnx: Improvements and fixes Kevin Wells
     [not found]     ` <a08234131003221009j1ec74009jc2eb289386455b65-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2010-04-05 23:00       ` Ben Dooks

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