Re: [PATCH v2] tty: serial: msm_serial.c: Cleaning up uninitialized variables

[Rickard Strandqvist]

2014-07-09 20:02 GMT+02:00 Stephen Boyd <sboyd@xxxxxxxxxxxxxx>:
> On 07/06/14 09:47, Rickard Strandqvist wrote:
>> Set reasonable initial value of some variables, in case
>> they do not get set to something otherwise.
>> And I've also added a plausibility control of the values.
>>
>> Signed-off-by: Rickard Strandqvist <rickard_strandqvist@xxxxxxxxxxxxxxxxxx>
>> ---
>
> This patch doesn't look right...
>
>> @@ -930,17 +930,21 @@ static int __init msm_console_setup(struct console *co, char *options)
>>
>>       msm_init_clock(port);
>>
>> -     if (options)
>> +     if (options) {
>>               uart_parse_options(options, &baud, &parity, &bits, &flow);
>> +             if (baud < 300 || baud > 115200)
>> +                     baud = 115200;
>> +             if (NULL == strchr("noeNOE", parity))
>> +                     parity = 'n';
>> +             if (bits != 7)
>> +                     bits = 8;
>> +             if (flow != 'r')
>> +                     flow = 'n';
>> +     }
>>
>> -     bits = 8;
>> -     parity = 'n';
>> -     flow = 'n';
>>       msm_write(port, UART_MR2_BITS_PER_CHAR_8 | UART_MR2_STOP_BIT_LEN_ONE,
>>                 UART_MR2);    /* 8N1 */
>>
>
> because this code is overriding whatever is parsed from
> uart_parse_options() on purpose. The hardware is configured for 8 bits,
> no parity, no flow control with this msm_write() statement. Maybe we
> should extend the code to configure the parity and flow control bits
> instead.



Hi

Okay, well that explains the strange code.
Maybe there should be a comment about this?

You mean that UART_MR2_BITS_PER_CHAR_8 | UART_MR2_STOP_BIT_LEN_ONE is
set correctly for the msm_write function?
I can do that...

Regardless, the original error whas that baud could be used uninitialized.


Kind regards
Rickard Strandqvist
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