Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752807AbbGNX2N (ORCPT ); Tue, 14 Jul 2015 19:28:13 -0400 Received: from seldrel01.sonyericsson.com ([37.139.156.2]:10792 "EHLO seldrel01.sonyericsson.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751818AbbGNX2I (ORCPT ); Tue, 14 Jul 2015 19:28:08 -0400 From: Tim Bird To: , , , CC: , , , , , Subject: [PATCH v2 2/3] ARM: qcom: Add coincell charger driver Date: Tue, 14 Jul 2015 16:26:19 -0700 Message-ID: <1436916380-3599-2-git-send-email-tim.bird@sonymobile.com> X-Mailer: git-send-email 1.8.2.2 In-Reply-To: <1436916380-3599-1-git-send-email-tim.bird@sonymobile.com> References: <1436916380-3599-1-git-send-email-tim.bird@sonymobile.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6461 Lines: 221 This driver is used to configure the coincell charger found in Qualcomm PMICs. The driver allows configuring the current-limiting resistor for the charger, as well as the voltage to apply to the coincell (or capacitor) when charging. Signed-off-by: Tim Bird --- Changes in v2: - (none in this file, but dts changes in 1/3 and 3/3) drivers/misc/Kconfig | 11 ++++ drivers/misc/Makefile | 1 + drivers/misc/qcom-coincell.c | 154 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 166 insertions(+) create mode 100644 drivers/misc/qcom-coincell.c diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index 42c3852..0909869 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -271,6 +271,17 @@ config HP_ILO To compile this driver as a module, choose M here: the module will be called hpilo. +config QCOM_COINCELL + tristate "Qualcomm coincell charger support" + depends on OF + select REGMAP + help + This driver supports the coincell block found inside of + Qualcomm PMICs. The coincell charger provides a means to + charge a coincell battery or backup capacitor which is used + to maintain PMIC register and RTC state in the absence of + external power. + config SGI_GRU tristate "SGI GRU driver" depends on X86_UV && SMP diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index d056fb7..537d7f3 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -18,6 +18,7 @@ obj-$(CONFIG_LKDTM) += lkdtm.o obj-$(CONFIG_TIFM_CORE) += tifm_core.o obj-$(CONFIG_TIFM_7XX1) += tifm_7xx1.o obj-$(CONFIG_PHANTOM) += phantom.o +obj-$(CONFIG_QCOM_COINCELL) += qcom-coincell.o obj-$(CONFIG_SENSORS_BH1780) += bh1780gli.o obj-$(CONFIG_SENSORS_BH1770) += bh1770glc.o obj-$(CONFIG_SENSORS_APDS990X) += apds990x.o diff --git a/drivers/misc/qcom-coincell.c b/drivers/misc/qcom-coincell.c new file mode 100644 index 0000000..9c019e4 --- /dev/null +++ b/drivers/misc/qcom-coincell.c @@ -0,0 +1,154 @@ +/* Copyright (c) 2013, The Linux Foundation. All rights reserved. + * Copyright (c) 2015, Sony Mobile Communications Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include +#include +#include +#include +#include + +struct qcom_coincell { + struct device *dev; + struct regmap *regmap; + u32 base_addr; +}; + +#define QCOM_COINCELL_REG_RSET 0x44 +#define QCOM_COINCELL_REG_VSET 0x45 +#define QCOM_COINCELL_REG_ENABLE 0x46 + +#define QCOM_COINCELL_ENABLE BIT(7) + +static const int qcom_rset_map[] = {2100, 1700, 1200, 800}; +static const int qcom_vset_map[] = {2500, 3200, 3100, 3000}; +/* NOTE: for pm8921 and others, voltage of 2500 is 16 (10000b), not 0 */ + +static int qcom_coincell_chgr_config(struct qcom_coincell *chgr, int rset, + int vset, int enable) +{ + int i, rc; + unsigned int value; + + /* select current-limiting resistor */ + for (i = 0; i < ARRAY_SIZE(qcom_rset_map); i++) + if (rset == qcom_rset_map[i]) + break; + + if (i >= ARRAY_SIZE(qcom_rset_map)) { + dev_err(chgr->dev, "invalid rset-ohms value %d\n", rset); + return -EINVAL; + } + + rc = regmap_write(chgr->regmap, + chgr->base_addr + QCOM_COINCELL_REG_RSET, i); + if (rc) + dev_err(chgr->dev, "could not write to RSET register\n"); + return rc; + + /* select charge voltage */ + for (i = 0; i < ARRAY_SIZE(qcom_vset_map); i++) + if (vset == qcom_vset_map[i]) + break; + + if (i >= ARRAY_SIZE(qcom_vset_map)) { + dev_err(chgr->dev, "invalid vset-millivolts value %d\n", vset); + return -EINVAL; + } + + rc = regmap_write(chgr->regmap, + chgr->base_addr + QCOM_COINCELL_REG_VSET, i); + if (rc) + dev_err(chgr->dev, "could not write to VSET register\n"); + return rc; + + /* set 'enable' register */ + value = enable ? QCOM_COINCELL_ENABLE : 0; + rc = regmap_write(chgr->regmap, + chgr->base_addr + QCOM_COINCELL_REG_ENABLE, value); + if (rc) + dev_err(chgr->dev, "could not write to ENABLE register\n"); + + return rc; +} + +static int qcom_coincell_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + struct qcom_coincell *chgr; + u32 rset, vset, enable; + int rc; + + if (!node) { + dev_err(&pdev->dev, "%s: device node missing\n", __func__); + return -ENODEV; + } + + chgr = devm_kzalloc(&pdev->dev, sizeof(*chgr), GFP_KERNEL); + if (!chgr) + return -ENOMEM; + + chgr->dev = &pdev->dev; + + chgr->regmap = dev_get_regmap(pdev->dev.parent, NULL); + if (!chgr->regmap) { + dev_err(chgr->dev, "Unable to get regmap\n"); + return -EINVAL; + } + + rc = of_property_read_u32(node, "reg", &chgr->base_addr); + if (rc) + return rc; + + rc = of_property_read_u32(node, "qcom,rset-ohms", &rset); + if (rc) { + dev_err(chgr->dev, "can't find 'qcom,rset-ohms' in DT block"); + return rc; + } + + rc = of_property_read_u32(node, "qcom,vset-millivolts", &vset); + if (rc) { + dev_err(chgr->dev, + "can't find 'qcom,vset-millivolts' in DT block"); + return rc; + } + + rc = of_property_read_u32(node, "qcom,charge-enable", &enable); + if (rc) + enable = 0; + + rc = qcom_coincell_chgr_config(chgr, rset, vset, enable); + + return rc; +} + +static const struct of_device_id qcom_coincell_match_table[] = { + { .compatible = "qcom,pm8941-coincell", }, + {} +}; + +MODULE_DEVICE_TABLE(of, qcom_coincell_match_table); + +static struct platform_driver qcom_coincell_driver = { + .driver = { + .name = "qcom,pm8941-coincell", + .of_match_table = qcom_coincell_match_table, + }, + .probe = qcom_coincell_probe, +}; + +module_platform_driver(qcom_coincell_driver); + +MODULE_DESCRIPTION("Qualcomm PMIC coincell charger driver"); +MODULE_LICENSE("GPL v2"); -- 1.8.2.2 -- 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/