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From: addy.ke@rock-chips.com (addy ke)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 1/2] spi/rockchip: fix bug that case spi can't go as fast as slave request
Date: Thu, 16 Oct 2014 17:16:02 +0800	[thread overview]
Message-ID: <543F8CD2.1010302@rock-chips.com> (raw)
In-Reply-To: <20141015130452.GD27755@sirena.org.uk>

hi, Mark

On 2014/10/15 21:04, Mark Brown wrote:
> On Wed, Oct 15, 2014 at 07:25:49PM +0800, Addy Ke wrote:
> 
>> +	if (WARN_ON(rs->speed > MAX_SCLK_OUT))
>> +		rs->speed = MAX_SCLK_OUT;
>> +
>> +	/* the minimum divsor is 2 */
>> +	if (rs->max_freq < 2 * rs->speed) {
>> +		clk_set_rate(rs->spiclk, 2 * rs->speed);
>> +		rs->max_freq = clk_get_rate(rs->spiclk);
>> +	}
> 
> I'll apply this but you should be checking the return code from
> clk_set_rate() here, please send a followup patch doing that.  It might

If clk_set_rate return error, do I only put dev_warn here or return error value to spi core?

> also be worth consdering just setting the rate unconditionally here, it
> seems like it should make things simpler.
> 
I think we need.
If we set the rate unconditionally here, clk_set_rate() will be executed in each spi transfer.

  reply	other threads:[~2014-10-16  9:16 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-10-15 11:25 [PATCH 0/2] spi: fix two bugs Addy Ke
2014-10-15 11:25 ` [PATCH 1/2] spi/rockchip: fix bug that case spi can't go as fast as slave request Addy Ke
2014-10-15 13:04   ` Mark Brown
2014-10-16  9:16     ` addy ke [this message]
2014-10-16  9:34       ` Mark Brown
2014-10-16  9:58         ` addy ke
2014-10-16 10:26           ` Mark Brown
2014-10-15 11:26 ` [PATCH 2/2] spi/rockchip: fix bug that cause spi transfer timed out in DMA duplex mode Addy Ke
2014-10-15 13:05   ` Mark Brown
2014-10-16  9:26     ` addy ke
2014-10-16  9:34       ` Mark Brown

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