From: wsa@the-dreams.de (Wolfram Sang)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency
Date: Fri, 22 Nov 2013 15:33:51 +0100 [thread overview]
Message-ID: <20131122143350.GA7420@katana> (raw)
In-Reply-To: <1385129228-11225-1-git-send-email-ludovic.desroches@atmel.com>
On Fri, Nov 22, 2013 at 03:07:08PM +0100, ludovic.desroches at atmel.com wrote:
> From: Ludovic Desroches <ludovic.desroches@atmel.com>
>
> There are still I2C unexpected behaviors which are solved by reducing TWI
> internal frequency.
>
> Cc: <stable@vger.kernel.org> #3.10+
> Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
I think the commit message needs more details. Is this a true bugfix
because the real bus frequency was too high because of the wrong
divider? Is this a workaround which makes things work but will make the
bus frequency slower than it should be?
> ---
> arch/arm/mach-at91/sama5d3.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm/mach-at91/sama5d3.c b/arch/arm/mach-at91/sama5d3.c
> index 4012797..4ee0de5 100644
> --- a/arch/arm/mach-at91/sama5d3.c
> +++ b/arch/arm/mach-at91/sama5d3.c
> @@ -95,19 +95,19 @@ static struct clk twi0_clk = {
> .name = "twi0_clk",
> .pid = SAMA5D3_ID_TWI0,
> .type = CLK_TYPE_PERIPHERAL,
> - .div = AT91_PMC_PCR_DIV2,
> + .div = AT91_PMC_PCR_DIV8,
> };
> static struct clk twi1_clk = {
> .name = "twi1_clk",
> .pid = SAMA5D3_ID_TWI1,
> .type = CLK_TYPE_PERIPHERAL,
> - .div = AT91_PMC_PCR_DIV2,
> + .div = AT91_PMC_PCR_DIV8,
> };
> static struct clk twi2_clk = {
> .name = "twi2_clk",
> .pid = SAMA5D3_ID_TWI2,
> .type = CLK_TYPE_PERIPHERAL,
> - .div = AT91_PMC_PCR_DIV2,
> + .div = AT91_PMC_PCR_DIV8,
> };
> static struct clk mmc0_clk = {
> .name = "mci0_clk",
> --
> 1.7.9.5
>
> --
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next prev parent reply other threads:[~2013-11-22 14:33 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-22 14:07 [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency ludovic.desroches at atmel.com
2013-11-22 14:33 ` Wolfram Sang [this message]
2013-11-22 14:51 ` Ludovic Desroches
2013-11-22 14:58 ` Wolfram Sang
2013-11-22 15:07 ` Ludovic Desroches
2013-11-22 15:09 ` Nicolas Ferre
2013-11-22 15:01 ` boris brezillon
2013-11-22 15:11 ` Nicolas Ferre
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