void __clk_put(struct clk *clk)
{
int ret;
ret = atomic_dec_return( &clk->use_cnt );
if( ret > 0 )
return;
BUG_ON( ret < 0 );
if( clk->parent )
__clk_put( clk->parent );
}
static int zclk_set_rate(struct clk *clk, unsigned long rate)
{
void __iomem *frqcrc;
int ret;
unsigned long step, p_rate;
u32 val;
if (!clk->parent || !__clk_get(clk->parent))
return -ENODEV;
if (!atomic_inc_and_test(&frqcr_lock) || !frqcr_kick_check(clk)) {
ret = -EBUSY;
goto done;
}
/*
* Users are supposed to first call clk_set_rate() only with
* clk_round_rate() results. So, we don't fix wrong rates here, but
* guard against them anyway
*/
p_rate = clk_get_rate(clk->parent);
if (rate == p_rate) {
val = 0;
} else {
step = DIV_ROUND_CLOSEST(p_rate, 32);
if (rate > p_rate || rate < step) {
ret = -EINVAL;
goto done;
}
val = 32 - rate / step;
}
frqcrc = clk->mapped_reg + (FRQCRC - (u32)clk->enable_reg);
iowrite32((ioread32(frqcrc) & ~(clk->div_mask << clk->enable_bit)) |
(val << clk->enable_bit), frqcrc);
ret = frqcr_kick_do(clk);
done:
atomic_dec(&frqcr_lock);
__clk_put(clk->parent);
return ret;
}
