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Date: Wed, 7 Feb 2024 09:34:02 +0000
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Joy Chakraborty <joychakr@google.com>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
	Rob Herring <robh@kernel.org>,
	Nicolas Saenz Julienne <nsaenz@kernel.org>,
	linux-kernel@vger.kernel.org, manugautam@google.com,
	stable@vger.kernel.org
Subject: Re: [PATCH v2] nvmem: rmem: Fix return value of rmem_read()
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On Tue, Feb 06, 2024 at 05:22:15PM +0530, Joy Chakraborty wrote:
> > > Userspace will see a false error with nvmem cell reads from
> > > nvmem_cell_attr_read() in current code, which should be fixed on
> > > returning 0 for success.
> >
> > So maybe fix this all up to allow the read to return the actual amount
> > read?  That feels more "correct" to me.
> >
> 
> If I change the behavior of the nvmem_reg_read_t callback to negative
> for error and number of bytes actually read for success then, other
> than the core driver I would also have to change all the
> nvmem-provider drivers.
> Is it okay to do so ?

Sure, why not?  That seems like the correct fix to me, right?

thanks,

greg k-h