Message-ID: <1379545361.1787.87.camel@joe-AO722>
Subject: Re: [PATCH v2] clk: si570: Add a driver for SI570 oscillators
From: Joe Perches <joe@perches.com>
To: Soren Brinkmann <soren.brinkmann@xilinx.com>
Cc: Rob Herring <rob.herring@calxeda.com>, Pawel Moll <pawel.moll@arm.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Stephen Warren <swarren@wwwdotorg.org>,
        Ian Campbell <ijc+devicetree@hellion.org.uk>,
        Rob Landley <rob@landley.net>, Mike Turquette <mturquette@linaro.org>,
        Grant Likely <grant.likely@linaro.org>,
        Guenter Roeck <linux@roeck-us.net>,
        Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>,
        devicetree@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        Hyun Kwon <hyunk@xilinx.com>
Date: Wed, 18 Sep 2013 16:02:41 -0700
In-Reply-To: <1379544219-23579-1-git-send-email-soren.brinkmann@xilinx.com>
References: <1379544219-23579-1-git-send-email-soren.brinkmann@xilinx.com>
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On Wed, 2013-09-18 at 15:43 -0700, Soren Brinkmann wrote:
> Add a driver for SILabs 570, 571, 598, 599 programmable oscillators.
> The devices generate low-jitter clock signals and are reprogrammable via
> an I2C interface.
[]
> v2:
[]
>  - use 10000 as MIN and MAX value in usleep_range
[]
> diff --git a/drivers/clk/clk-si570.c b/drivers/clk/clk-si570.c
[]
> +static int si570_set_frequency(struct clk_si570 *data, unsigned long frequency)
> +{
[]
> +	/* Applying a new frequency can take up to 10ms */
> +	usleep_range(10000, 10000);

Generally it's nicer to have an actual range for usleep_range.

Is there a bit you could periodically poll to see
if the new frequency has been set or is stable so
that a 10ms delay isn't always used?


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