Re: [RFT PATCH] regmap-i2c: Only use I2C_FUNC_I2C if val_bits == 8

From	Guenter Roeck <linux@roeck-us.net>
Newsgroups	linux.kernel
Subject	Re: [RFT PATCH] regmap-i2c: Only use I2C_FUNC_I2C if val_bits == 8
Date	2016-06-25 17:10 +0200
Message-ID	<rNXnA-71S-5@gated-at.bofh.it> (permalink)
References	<rNLZ8-8gc-1@gated-at.bofh.it> <rNU6l-4TK-5@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On 06/25/2016 04:34 AM, Mark Brown wrote:
> On Fri, Jun 24, 2016 at 07:53:53PM -0700, Guenter Roeck wrote:
>
>> On chips with a register value size of 16 bits, I2C block reads will
>> typically not return the expected values. Instead, returned values
>> are most likely undefined if an operation crosses a register boundary.
>
> No, this just isn't true in general - if a device has trouble with bulk
> reads it needs to set use_sigle_rw in the config to disable them.
> Device limitations with bulk reads are a per device thing and are
> orthogonal to the value size, being more to do with the age and quality
> of the register map implementation than anything else.
>

Ok, thanks for letting me know. I'll try that.

Guenter

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[RFT PATCH] regmap-i2c: Only use I2C_FUNC_I2C if val_bits == 8 Guenter Roeck <linux@roeck-us.net> - 2016-06-25 05:00 +0200
  Re: [RFT PATCH] regmap-i2c: Only use I2C_FUNC_I2C if val_bits == 8 Mark Brown <broonie@kernel.org> - 2016-06-25 13:40 +0200
    Re: [RFT PATCH] regmap-i2c: Only use I2C_FUNC_I2C if val_bits == 8 Guenter Roeck <linux@roeck-us.net> - 2016-06-25 17:10 +0200

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