Message-ID: <1340104522.3964.1.camel@phoenix>
Subject: regulator: tps6586x: What is the meaning of TPS6586X_SLEW_RATE_SET
 setting?
From: Axel Lin <axel.lin@gmail.com>
To: linux-kernel@vger.kernel.org
Cc: Mike Rapoport <mike@compulab.co.il>, Danny Huang <dahuang@nvidia.com>,
        Liam Girdwood <lrg@ti.com>,
        Mark Brown <broonie@opensource.wolfsonmicro.com>
Date: Tue, 19 Jun 2012 19:15:22 +0800
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Hi Mike,
While looking at the datasheet (tps65860 and tps65862),
I don't understand why we have TPS6586X_SLEW_RATE_SET (0x08) in the code.

According to the datasheet, BIT3 of SM1SL/SM0SL is not used:

SM1SL [Addr 0x25]
SM0SL [Addr 0x28]
        BIT[2:0] SM0/SM1 SUPPLY RAMP RATE
        BIT[7:3] NOT USED

So why we need to check the "unused bit" in tps6586x_regulator_set_slew_rate()?

        if (!(setting->slew_rate & TPS6586X_SLEW_RATE_SET))
                return 0;

Regards,
Axel

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