ARM: qcom: Add coincell charger driver (1f26d1c1) · Commits · e / devices / android_kernel_teracube_2e

drivers/misc/Kconfig

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		@@ -271,6 +271,16 @@ 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 MFD_SPMI_PMIC \|\| COMPILE_TEST
		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

drivers/misc/Makefile

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		@@ -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

drivers/misc/qcom-coincell.c

0 → 100644

+152 −0

Original line number	Diff line number	Diff line
		/* 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 <linux/kernel.h>
		#include <linux/module.h>
		#include <linux/slab.h>
		#include <linux/of.h>
		#include <linux/regmap.h>
		#include <linux/of_device.h>
		#include <linux/platform_device.h>

		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 */

		/* if enable==0, rset and vset are ignored */
		static int qcom_coincell_chgr_config(struct qcom_coincell *chgr, int rset,
		int vset, bool enable)
		{
		int i, j, rc;

		/* if disabling, just do that and skip other operations */
		if (!enable)
		return regmap_write(chgr->regmap,
		chgr->base_addr + QCOM_COINCELL_REG_ENABLE, 0);

		/* find index for 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;
		}

		/* find index for charge voltage */
		for (j = 0; j < ARRAY_SIZE(qcom_vset_map); j++)
		if (vset == qcom_vset_map[j])
		break;

		if (j >= 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_RSET, i);
		if (rc) {
		/*
		* This is mainly to flag a bad base_addr (reg) from dts.
		* Other failures writing to the registers should be
		* extremely rare, or indicative of problems that
		* should be reported elsewhere (eg. spmi failure).
		*/
		dev_err(chgr->dev, "could not write to RSET register\n");
		return rc;
		}

		rc = regmap_write(chgr->regmap,
		chgr->base_addr + QCOM_COINCELL_REG_VSET, j);
		if (rc)
		return rc;

		/* set 'enable' register */
		return regmap_write(chgr->regmap,
		chgr->base_addr + QCOM_COINCELL_REG_ENABLE,
		QCOM_COINCELL_ENABLE);
		}

		static int qcom_coincell_probe(struct platform_device *pdev)
		{
		struct device_node *node = pdev->dev.of_node;
		struct qcom_coincell chgr;
		u32 rset, vset;
		bool enable;
		int rc;

		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;

		enable = !of_property_read_bool(node, "qcom,charger-disable");

		if (enable) {
		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;
		}
		}

		return qcom_coincell_chgr_config(&chgr, rset, vset, enable);
		}

		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-spmi-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");