[U-Boot] [PATCH v3 04/23] i2c: Add TPS6586X driver

[Simon Glass]

Hi Stephen,

On Mon, Apr 9, 2012 at 2:01 PM, Stephen Warren <swarren at wwwdotorg.org> wrote:
> On 04/02/2012 05:18 PM, Simon Glass wrote:
>> This power management chip supports battery charging and a large number
>> of power supplies. This initial driver only provides the ability to adjust
>> the two synchronous buck converters SM0 and SM1 in a stepwise manner.
>>
>> Signed-off-by: Simon Glass <sjg at chromium.org>
>
>> +#define MAX_I2C_RETRY        3
>> +int tps6586x_read(int reg)
> ...
>> +     for (i = 0; i < MAX_I2C_RETRY; ++i) {
>> +             if (!i2c_read(I2C_ADDRESS, reg, 1, &data, 1)) {
>> +                     retval = (int)data;
>> +                     goto exit;
>> +             }
>> +
>> +             /* i2c access failed, retry */
>> +             udelay(100);
>> +     }
>
> Why do we need this retry logic; the kernel driver doesn't appear to
> have this.

We apparently have found the device to be flaky on i2c sometimes,
which is why this is here.

Regards,
Simon