From patchwork Mon Sep 28 22:33:56 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andreas Dannenberg X-Patchwork-Id: 7281401 Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id B74189F39B for ; Mon, 28 Sep 2015 22:35:24 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id CFADC20734 for ; Mon, 28 Sep 2015 22:35:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D439020726 for ; Mon, 28 Sep 2015 22:35:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754627AbbI1WfV (ORCPT ); Mon, 28 Sep 2015 18:35:21 -0400 Received: from arroyo.ext.ti.com ([192.94.94.40]:60543 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754475AbbI1WfT (ORCPT ); Mon, 28 Sep 2015 18:35:19 -0400 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by arroyo.ext.ti.com (8.13.7/8.13.7) with ESMTP id t8SMYYIX029935; Mon, 28 Sep 2015 17:34:35 -0500 Received: from DLEE71.ent.ti.com (dlee71.ent.ti.com [157.170.170.114]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id t8SMYYLh021950; Mon, 28 Sep 2015 17:34:34 -0500 Received: from dflp32.itg.ti.com (10.64.6.15) by DLEE71.ent.ti.com (157.170.170.114) with Microsoft SMTP Server id 14.3.224.2; Mon, 28 Sep 2015 17:34:35 -0500 Received: from beast.tx.rr.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dflp32.itg.ti.com (8.14.3/8.13.8) with ESMTP id t8SMY56H026609; Mon, 28 Sep 2015 17:34:32 -0500 From: Andreas Dannenberg To: Sebastian Reichel , Dmitry Eremin-Solenikov , David Woodhouse , Laurentiu Palcu , Krzysztof Kozlowski CC: Ramakrishna Pallala , , , , Andreas Dannenberg Subject: [PATCH v8 08/14] power: bq24257: Add SW-based approach for Power Good determination Date: Mon, 28 Sep 2015 17:33:56 -0500 Message-ID: <1443479642-23712-9-git-send-email-dannenberg@ti.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1443479642-23712-1-git-send-email-dannenberg@ti.com> References: <1443479642-23712-1-git-send-email-dannenberg@ti.com> MIME-Version: 1.0 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP A software-based approach for determining the charger's input voltage "Power Good" state is introduced for devices like the bq24250 which don't have a dedicated hardware pin for that purpose. This SW-based approach is also used for other devices (with dedicated PG pin) as a fall back solution if that pin is not configured to be used through "pg-gpios". Signed-off-by: Andreas Dannenberg Reviewed-by: Krzysztof Kozlowski --- drivers/power/bq24257_charger.c | 56 +++++++++++++++++++++++++++++++++-------- 1 file changed, 45 insertions(+), 11 deletions(-) diff --git a/drivers/power/bq24257_charger.c b/drivers/power/bq24257_charger.c index 7bbff80..15e0e93 100644 --- a/drivers/power/bq24257_charger.c +++ b/drivers/power/bq24257_charger.c @@ -359,7 +359,26 @@ static int bq24257_get_chip_state(struct bq24257_device *bq, state->fault = ret; - state->power_good = !gpiod_get_value_cansleep(bq->pg); + if (bq->pg) + state->power_good = !gpiod_get_value_cansleep(bq->pg); + else + /* + * If we have a chip without a dedicated power-good GPIO or + * some other explicit bit that would provide this information + * assume the power is good if there is no supply related + * fault - and not good otherwise. There is a possibility for + * other errors to mask that power in fact is not good but this + * is probably the best we can do here. + */ + switch (state->fault) { + case FAULT_INPUT_OVP: + case FAULT_INPUT_UVLO: + case FAULT_INPUT_LDO_LOW: + state->power_good = false; + break; + default: + state->power_good = true; + } return 0; } @@ -651,15 +670,21 @@ static int bq24257_power_supply_init(struct bq24257_device *bq) return PTR_ERR_OR_ZERO(bq->charger); } -static int bq24257_pg_gpio_probe(struct bq24257_device *bq) +static void bq24257_pg_gpio_probe(struct bq24257_device *bq) { - bq->pg = devm_gpiod_get_index(bq->dev, BQ24257_PG_GPIO, 0, GPIOD_IN); - if (IS_ERR(bq->pg)) { - dev_err(bq->dev, "could not probe PG pin\n"); - return PTR_ERR(bq->pg); + bq->pg = devm_gpiod_get_optional(bq->dev, BQ24257_PG_GPIO, GPIOD_IN); + + if (PTR_ERR(bq->pg) == -EPROBE_DEFER) { + dev_info(bq->dev, "probe retry requested for PG pin\n"); + return; + } else if (IS_ERR(bq->pg)) { + dev_err(bq->dev, "error probing PG pin\n"); + bq->pg = NULL; + return; } - return 0; + if (bq->pg) + dev_dbg(bq->dev, "probed PG pin = %d\n", desc_to_gpio(bq->pg)); } static int bq24257_fw_probe(struct bq24257_device *bq) @@ -789,10 +814,19 @@ static int bq24257_probe(struct i2c_client *client, INIT_DELAYED_WORK(&bq->iilimit_setup_work, bq24257_iilimit_setup_work); - /* we can only check Power Good status by probing the PG pin */ - ret = bq24257_pg_gpio_probe(bq); - if (ret < 0) - return ret; + /* + * The BQ24250 doesn't have a dedicated Power Good (PG) pin so let's + * not probe for it and instead use a SW-based approach to determine + * the PG state. We also use a SW-based approach for all other devices + * if the PG pin is either not defined or can't be probed. + */ + if (bq->chip != BQ24250) + bq24257_pg_gpio_probe(bq); + + if (PTR_ERR(bq->pg) == -EPROBE_DEFER) + return PTR_ERR(bq->pg); + else if (!bq->pg) + dev_info(bq->dev, "using SW-based power-good detection\n"); /* reset all registers to defaults */ ret = bq24257_field_write(bq, F_RESET, 1);