From patchwork Wed May 13 18:56:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sebastian Reichel X-Patchwork-Id: 212039 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, UNPARSEABLE_RELAY, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C66B9C433E3 for ; Wed, 13 May 2020 18:56:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7F9222054F for ; Wed, 13 May 2020 18:57:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390418AbgEMS4i (ORCPT ); Wed, 13 May 2020 14:56:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49958 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S2390413AbgEMS4h (ORCPT ); Wed, 13 May 2020 14:56:37 -0400 Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AF0BEC061A0C; Wed, 13 May 2020 11:56:37 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: sre) with ESMTPSA id 9F2C02A27A9 Received: by jupiter.universe (Postfix, from userid 1000) id 90659480110; Wed, 13 May 2020 20:56:29 +0200 (CEST) From: Sebastian Reichel To: Sebastian Reichel , Rob Herring , Greg Kroah-Hartman , "Rafael J . Wysocki" Cc: linux-pm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, kernel@collabora.com, Jean-Francois Dagenais , Sebastian Reichel Subject: [PATCHv1 15/19] power: supply: sbs-battery: add ability to disable charger broadcasts Date: Wed, 13 May 2020 20:56:11 +0200 Message-Id: <20200513185615.508236-16-sebastian.reichel@collabora.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200513185615.508236-1-sebastian.reichel@collabora.com> References: <20200513185615.508236-1-sebastian.reichel@collabora.com> MIME-Version: 1.0 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: Jean-Francois Dagenais In certain designs, it is possible to add a battery on a populated i2c bus without an sbs compliant charger. In that case, the battery will un-necessarily and sometimes un-desirably master the bus trying to write info in the charger. It is observed in many occasion that these battery "broadcasts" are even corrupting other ongoing master to slave communication. I.e. the multi-master support in the battery is inadequate. Thankfully, the CHARGER_MODE bit allows designers to disable that SBS battery behaviour. This needs to be done once when the battery is first seen on the bus. Signed-off-by: Jean-Francois Dagenais [rebased code] Signed-off-by: Sebastian Reichel --- .../bindings/power/supply/sbs_sbs-battery.txt | 2 ++ drivers/power/supply/sbs-battery.c | 29 +++++++++++++++++++ 2 files changed, 31 insertions(+) diff --git a/Documentation/devicetree/bindings/power/supply/sbs_sbs-battery.txt b/Documentation/devicetree/bindings/power/supply/sbs_sbs-battery.txt index fa5a8b516dbf..a5093ccef5c5 100644 --- a/Documentation/devicetree/bindings/power/supply/sbs_sbs-battery.txt +++ b/Documentation/devicetree/bindings/power/supply/sbs_sbs-battery.txt @@ -16,6 +16,7 @@ Optional properties : after an external change notification. - sbs,battery-detect-gpios : The gpio which signals battery detection and a flag specifying its polarity. + - sbs,disable-charger-broadcasts: for systems without sbs compliant chargers Example: @@ -25,4 +26,5 @@ Example: sbs,i2c-retry-count = <2>; sbs,poll-retry-count = <10>; sbs,battery-detect-gpios = <&gpio-controller 122 1>; + sbs,disable-charger-broadcasts; } diff --git a/drivers/power/supply/sbs-battery.c b/drivers/power/supply/sbs-battery.c index e3c685b2c247..7c6905a486da 100644 --- a/drivers/power/supply/sbs-battery.c +++ b/drivers/power/supply/sbs-battery.c @@ -68,6 +68,7 @@ enum sbs_capacity_mode { CAPACITY_MODE_AMPS = 0, CAPACITY_MODE_WATTS = BATTERY_MODE_CAPACITY_MASK }; +#define BATTERY_MODE_CHARGER_MASK (1<<14) /* manufacturer access defines */ #define MANUFACTURER_ACCESS_STATUS 0x0006 @@ -193,6 +194,7 @@ struct sbs_info { bool is_present; struct gpio_desc *gpio_detect; bool enable_detection; + bool charger_broadcasts; int last_state; int poll_time; u32 i2c_retry_count; @@ -207,6 +209,27 @@ static char manufacturer[I2C_SMBUS_BLOCK_MAX + 1]; static char chemistry[I2C_SMBUS_BLOCK_MAX + 1]; static bool force_load; +static int sbs_read_word_data(struct i2c_client *client, u8 address); +static int sbs_write_word_data(struct i2c_client *client, u8 address, u16 value); + +static void sbs_disable_charger_broadcasts(struct sbs_info *chip) +{ + int val = sbs_read_word_data(chip->client, BATTERY_MODE_OFFSET); + if (val < 0) + goto exit; + + val |= BATTERY_MODE_CHARGER_MASK; + + val = sbs_write_word_data(chip->client, BATTERY_MODE_OFFSET, val); + +exit: + if (val < 0) + dev_err(&chip->client->dev, + "Failed to disable charger broadcasting: %d\n", val); + else + dev_dbg(&chip->client->dev, "%s\n", __func__); +} + static int sbs_update_presence(struct sbs_info *chip, bool is_present) { struct i2c_client *client = chip->client; @@ -260,6 +283,9 @@ static int sbs_update_presence(struct sbs_info *chip, bool is_present) dev_dbg(&client->dev, "PEC: %s\n", (client->flags & I2C_CLIENT_PEC) ? "enabled" : "disabled"); + if (!chip->is_present && is_present && !chip->charger_broadcasts) + sbs_disable_charger_broadcasts(chip); + chip->is_present = true; return 0; @@ -1017,6 +1043,9 @@ static int sbs_probe(struct i2c_client *client, } chip->i2c_retry_count = chip->i2c_retry_count + 1; + chip->charger_broadcasts = !of_property_read_bool(client->dev.of_node, + "sbs,disable-charger-broadcasts"); + chip->gpio_detect = devm_gpiod_get_optional(&client->dev, "sbs,battery-detect", GPIOD_IN); if (IS_ERR(chip->gpio_detect)) {