Re: [v2 3/4] platform: (TS-5500) add LED support

From: H. Peter Anvin
Date: Tue Aug 30 2011 - 01:38:34 EST


On 08/29/2011 03:16 PM, Mark Brown wrote:
> On Fri, Aug 26, 2011 at 07:40:26PM -0400, Vivien Didelot wrote:
>
>> +static void ts5500_led_work(struct work_struct *work)
>> +{
>> + struct ts5500_led *led = container_of(work, struct ts5500_led, work);
>> + u8 val = led->new_brightness ? led->bit : 0;
>> +
>> + outb(val, led->ioaddr);
>> +}
>
> Can you not do outb() from atomic context? The reason lots of LED
> drivers update the hardware in a workqueue is that they communicate with
> the hardware over buses that can't be used in atomic context like I2C or
> SPI but if that's not an issue then the workqueue is not required and
> the code can be simplified.

outb() can definitely be executed from atomic context.

-hpa
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