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Date: Thu, 2 May 2024 15:30:29 +0800
From: Alina Yu <alina_yu@richtek.com>
To: Mark Brown <broonie@kernel.org>
CC: <lgirdwood@gmail.com>, <linux-kernel@vger.kernel.org>,
	<johnny_lai@richtek.com>, <cy_huang@richtek.com>
Subject: Re: [PATCH v2 2/4] regulator: rtq2208: Fix LDO to be compatible with
 both fixed and adjustable vout
Message-ID: <20240502073029.GA4055@linuxcarl2.richtek.com>
References: <cover.1714467553.git.alina_yu@richtek.com>
 <ffeecd61c194df1f7f049bd50cb2bbbad3cf1025.1714467553.git.alina_yu@richtek.com>
 <ZjGmmYWHu-ZQQdIh@finisterre.sirena.org.uk>
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On Wed, May 01, 2024 at 11:19:05AM +0900, Mark Brown wrote:
> On Tue, Apr 30, 2024 at 05:58:25PM +0800, Alina Yu wrote:
> 
> > In this patch, LDO's adjustable and fixed Vout settings are compatible.
> > The LDO Vout ability depends on the init_data->constraints.
> > If adjustable, the Vout can be set to either 1800mV or 3300mV.
> 
> > +		if (init_data->constraints.min_uV == init_data->constraints.max_uV) {
> > +			desc->n_voltages = 1;
> > +			desc->fixed_uV = init_data->constraints.min_uV;
> > +			desc->ops = &rtq2208_regulator_ldo_fix_ops;
> > +		} else {
> > +			desc->n_voltages = ARRAY_SIZE(rtq2208_ldo_volt_table);
> > +			desc->volt_table = rtq2208_ldo_volt_table;
> > +			desc->ops = &rtq2208_regulator_ldo_adj_ops;
> > +		}
> 
> Why are you making this change?  The operations supported by the
> regulator don't change depending on if the system is going to chnage the
> voltage.

The change is necessary due to the requirement of the SD card for high/default and ultra-high-speed modes. The system needs to adjust the LDO Vout accordingly.
In ultra-high-speed mode, the LDO Vout needs to be adjusted to 1.8V; otherwise, it will remain at 1.8V.


Thanks,
Alina