Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754040AbaBDJFR (ORCPT ); Tue, 4 Feb 2014 04:05:17 -0500 Received: from eusmtp01.atmel.com ([212.144.249.243]:22655 "EHLO eusmtp01.atmel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750937AbaBDJFC (ORCPT ); Tue, 4 Feb 2014 04:05:02 -0500 Message-ID: <52F0AD31.6060200@atmel.com> Date: Tue, 4 Feb 2014 10:04:49 +0100 From: Nicolas Ferre Organization: atmel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-Version: 1.0 To: Boris BREZILLON , Mike Turquette CC: , Subject: Re: [PATCH 2/3] clk: at91: replace prog clk round_rate with determine_rate References: <1391426731-9392-1-git-send-email-b.brezillon@overkiz.com> <1391426731-9392-3-git-send-email-b.brezillon@overkiz.com> In-Reply-To: <1391426731-9392-3-git-send-email-b.brezillon@overkiz.com> X-Enigmail-Version: 1.5.2 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.161.30.18] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/02/2014 12:25, Boris BREZILLON : > Implement the determine_rate callback to choose the best parent clk that > fulfills the requested rate. > > Signed-off-by: Boris BREZILLON Acked-by: Nicolas Ferre Nice feature, thanks! > --- > drivers/clk/at91/clk-programmable.c | 56 +++++++++++++++++------------------ > 1 file changed, 28 insertions(+), 28 deletions(-) > > diff --git a/drivers/clk/at91/clk-programmable.c b/drivers/clk/at91/clk-programmable.c > index 02f62a0..8e242c7 100644 > --- a/drivers/clk/at91/clk-programmable.c > +++ b/drivers/clk/at91/clk-programmable.c > @@ -105,40 +105,40 @@ static unsigned long clk_programmable_recalc_rate(struct clk_hw *hw, > return parent_rate >> prog->pres; > } > > -static long clk_programmable_round_rate(struct clk_hw *hw, unsigned long rate, > - unsigned long *parent_rate) > +static long clk_programmable_determine_rate(struct clk_hw *hw, > + unsigned long rate, > + unsigned long *best_parent_rate, > + struct clk **best_parent_clk) > { > - unsigned long best_rate = *parent_rate; > - unsigned long best_diff; > - unsigned long new_diff; > - unsigned long cur_rate; > - int shift = shift; > - > - if (rate > *parent_rate) > - return *parent_rate; > - else > - best_diff = *parent_rate - rate; > - > - if (!best_diff) > - return best_rate; > + struct clk *parent = NULL; > + long best_rate = -EINVAL; > + unsigned long parent_rate; > + unsigned long tmp_rate; > + int shift; > + int i; > > - for (shift = 1; shift < PROG_PRES_MASK; shift++) { > - cur_rate = *parent_rate >> shift; > + for (i = 0; i < __clk_get_num_parents(hw->clk); i++) { > + parent = clk_get_parent_by_index(hw->clk, i); > + if (!parent) > + continue; > > - if (cur_rate > rate) > - new_diff = cur_rate - rate; > - else > - new_diff = rate - cur_rate; > + parent_rate = __clk_get_rate(parent); > + for (shift = 0; shift < PROG_PRES_MASK; shift++) { > + tmp_rate = parent_rate >> shift; > + if (tmp_rate <= rate) > + break; > + } > > - if (!new_diff) > - return cur_rate; > + if (tmp_rate > rate) > + continue; > > - if (new_diff < best_diff) { > - best_diff = new_diff; > - best_rate = cur_rate; > + if (best_rate < 0 || (rate - tmp_rate) < (rate - best_rate)) { > + best_rate = tmp_rate; > + *best_parent_rate = parent_rate; > + *best_parent_clk = parent; > } > > - if (rate > cur_rate) > + if (!best_rate) > break; > } > > @@ -231,7 +231,7 @@ static const struct clk_ops programmable_ops = { > .prepare = clk_programmable_prepare, > .is_prepared = clk_programmable_is_ready, > .recalc_rate = clk_programmable_recalc_rate, > - .round_rate = clk_programmable_round_rate, > + .determine_rate = clk_programmable_determine_rate, > .get_parent = clk_programmable_get_parent, > .set_parent = clk_programmable_set_parent, > .set_rate = clk_programmable_set_rate, > -- Nicolas Ferre -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/