[Bug 392812] Re: Dell Studio 1555: cannot change display brightness after a while, other hotkeys and ACPI stuff begin to fail

[vlowther]

Commenting out the goto end; line in acpi_ec_transaction and recompiling
the kernel from source works around the bug for me -- I still get the
"input buffer not empty" error messages in dmesg, but the brightness
keys and AC adapter detection continue to work.

static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t,
                               int force_poll)                           
{                                                                        
        int status;                                                      
        u32 glk;                                                         
        if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
                return -EINVAL;                                             
        if (t->rdata)                                                       
                memset(t->rdata, 0, t->rlen);                               
        mutex_lock(&ec->lock);                                              
        if (ec->global_lock) {                                              
                status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
                if (ACPI_FAILURE(status)) {                                 
                        status = -ENODEV;                                   
                        goto unlock;                                        
                }                                                           
        }                                                                   
        if (ec_wait_ibf0(ec)) {                                             
                pr_err(PREFIX "input buffer is not empty, "                 
                                "aborting transaction--\n");                
                status = -ETIME;                                            
                //goto end;                                                 

        }
        status = acpi_ec_transaction_unlocked(ec, t, force_poll);
end:                                                             
        if (ec->global_lock)                                     
                acpi_release_global_lock(glk);                   
unlock:                                                          
        mutex_unlock(&ec->lock);                                 
        return status;                                           
}

-- 
Dell Studio 1555: cannot change display brightness after a while, other hotkeys and ACPI stuff begin to fail
https://bugs.launchpad.net/bugs/392812
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