From mboxrd@z Thu Jan 1 00:00:00 1970 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 8D665C433E0 for ; Wed, 13 May 2020 18:57:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 504722065C for ; Wed, 13 May 2020 18:57:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390494AbgEMS5K (ORCPT ); Wed, 13 May 2020 14:57:10 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:51916 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390383AbgEMS4g (ORCPT ); Wed, 13 May 2020 14:56:36 -0400 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: sre) with ESMTPSA id 4FD212A28AB Received: by jupiter.universe (Postfix, from userid 1000) id 7AAD6480106; 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, Sebastian Reichel Subject: [PATCHv1 08/19] power: supply: sbs-battery: add PEC support Date: Wed, 13 May 2020 20:56:04 +0200 Message-Id: <20200513185615.508236-9-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 Content-Transfer-Encoding: 8bit Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org SBS batteries optionally have support for PEC. This enables PEC handling based on the implemented SBS version as suggested by the standard. The support for PEC is re-evaluated when the battery is hotplugged into the system, since there might be systems supporting batteries from different SBS generations. Signed-off-by: Sebastian Reichel --- drivers/power/supply/sbs-battery.c | 72 ++++++++++++++++++++++++++++-- 1 file changed, 69 insertions(+), 3 deletions(-) diff --git a/drivers/power/supply/sbs-battery.c b/drivers/power/supply/sbs-battery.c index a9a1d28dabbe..ab774d491269 100644 --- a/drivers/power/supply/sbs-battery.c +++ b/drivers/power/supply/sbs-battery.c @@ -46,6 +46,14 @@ enum { REG_MODEL_NAME, }; +#define REG_ADDR_SPEC_INFO 0x1A +#define SPEC_INFO_VERSION_MASK GENMASK(7, 4) +#define SPEC_INFO_VERSION_SHIFT 4 + +#define SBS_VERSION_1_0 1 +#define SBS_VERSION_1_1 2 +#define SBS_VERSION_1_1_WITH_PEC 3 + /* Battery Mode defines */ #define BATTERY_MODE_OFFSET 0x03 #define BATTERY_MODE_CAPACITY_MASK BIT(15) @@ -175,6 +183,64 @@ static char model_name[I2C_SMBUS_BLOCK_MAX + 1]; static char manufacturer[I2C_SMBUS_BLOCK_MAX + 1]; static bool force_load; +static int sbs_update_presence(struct sbs_info *chip, bool is_present) +{ + struct i2c_client *client = chip->client; + int retries = chip->i2c_retry_count; + s32 ret = 0; + u8 version; + + if (chip->is_present == is_present) + return 0; + + if (!is_present) { + chip->is_present = false; + /* Disable PEC when no device is present */ + client->flags &= ~I2C_CLIENT_PEC; + return 0; + } + + /* Check if device supports packet error checking and use it */ + while (retries > 0) { + ret = i2c_smbus_read_word_data(client, REG_ADDR_SPEC_INFO); + if (ret >= 0) + break; + + /* + * Some batteries trigger the detection pin before the + * I2C bus is properly connected. This works around the + * issue. + */ + msleep(100); + + retries--; + } + + if (ret < 0) { + dev_dbg(&client->dev, "failed to read spec info: %d\n", ret); + + /* fallback to old behaviour */ + client->flags &= ~I2C_CLIENT_PEC; + chip->is_present = true; + + return ret; + } + + version = (ret & SPEC_INFO_VERSION_MASK) >> SPEC_INFO_VERSION_SHIFT; + + if (version == SBS_VERSION_1_1_WITH_PEC) + client->flags |= I2C_CLIENT_PEC; + else + client->flags &= ~I2C_CLIENT_PEC; + + dev_dbg(&client->dev, "PEC: %s\n", (client->flags & I2C_CLIENT_PEC) ? + "enabled" : "disabled"); + + chip->is_present = true; + + return 0; +} + static int sbs_read_word_data(struct i2c_client *client, u8 address) { struct sbs_info *chip = i2c_get_clientdata(client); @@ -579,7 +645,7 @@ static int sbs_get_property(struct power_supply *psy, return ret; if (psp == POWER_SUPPLY_PROP_PRESENT) { val->intval = ret; - chip->is_present = val->intval; + sbs_update_presence(chip, ret); return 0; } if (ret == 0) @@ -678,7 +744,7 @@ static int sbs_get_property(struct power_supply *psy, if (!chip->gpio_detect && chip->is_present != (ret >= 0)) { - chip->is_present = (ret >= 0); + sbs_update_presence(chip, (ret >= 0)); power_supply_changed(chip->power_supply); } @@ -709,7 +775,7 @@ static void sbs_supply_changed(struct sbs_info *chip) ret = gpiod_get_value_cansleep(chip->gpio_detect); if (ret < 0) return; - chip->is_present = ret; + sbs_update_presence(chip, ret); power_supply_changed(battery); } -- 2.26.2