cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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tps65217_charger.c (7260B)


      1// SPDX-License-Identifier: GPL-2.0
      2// Battery charger driver for TI's tps65217
      3//
      4// Copyright (C) 2015 Collabora Ltd.
      5// Author: Enric Balletbo i Serra <enric.balletbo@collabora.com>
      6
      7/*
      8 * Battery charger driver for TI's tps65217
      9 */
     10#include <linux/kernel.h>
     11#include <linux/kthread.h>
     12#include <linux/device.h>
     13#include <linux/module.h>
     14#include <linux/platform_device.h>
     15#include <linux/init.h>
     16#include <linux/interrupt.h>
     17#include <linux/slab.h>
     18#include <linux/err.h>
     19#include <linux/of.h>
     20#include <linux/of_device.h>
     21#include <linux/power_supply.h>
     22
     23#include <linux/mfd/core.h>
     24#include <linux/mfd/tps65217.h>
     25
     26#define CHARGER_STATUS_PRESENT	(TPS65217_STATUS_ACPWR | TPS65217_STATUS_USBPWR)
     27#define NUM_CHARGER_IRQS	2
     28#define POLL_INTERVAL		(HZ * 2)
     29
     30struct tps65217_charger {
     31	struct tps65217 *tps;
     32	struct device *dev;
     33	struct power_supply *psy;
     34
     35	int	online;
     36	int	prev_online;
     37
     38	struct task_struct	*poll_task;
     39};
     40
     41static enum power_supply_property tps65217_charger_props[] = {
     42	POWER_SUPPLY_PROP_ONLINE,
     43};
     44
     45static int tps65217_config_charger(struct tps65217_charger *charger)
     46{
     47	int ret;
     48
     49	/*
     50	 * tps65217 rev. G, p. 31 (see p. 32 for NTC schematic)
     51	 *
     52	 * The device can be configured to support a 100k NTC (B = 3960) by
     53	 * setting the the NTC_TYPE bit in register CHGCONFIG1 to 1. However it
     54	 * is not recommended to do so. In sleep mode, the charger continues
     55	 * charging the battery, but all register values are reset to default
     56	 * values. Therefore, the charger would get the wrong temperature
     57	 * information. If 100k NTC setting is required, please contact the
     58	 * factory.
     59	 *
     60	 * ATTENTION, conflicting information, from p. 46
     61	 *
     62	 * NTC TYPE (for battery temperature measurement)
     63	 *   0 – 100k (curve 1, B = 3960)
     64	 *   1 – 10k  (curve 2, B = 3480) (default on reset)
     65	 *
     66	 */
     67	ret = tps65217_clear_bits(charger->tps, TPS65217_REG_CHGCONFIG1,
     68				  TPS65217_CHGCONFIG1_NTC_TYPE,
     69				  TPS65217_PROTECT_NONE);
     70	if (ret) {
     71		dev_err(charger->dev,
     72			"failed to set 100k NTC setting: %d\n", ret);
     73		return ret;
     74	}
     75
     76	return 0;
     77}
     78
     79static int tps65217_enable_charging(struct tps65217_charger *charger)
     80{
     81	int ret;
     82
     83	/* charger already enabled */
     84	if (charger->online)
     85		return 0;
     86
     87	dev_dbg(charger->dev, "%s: enable charging\n", __func__);
     88	ret = tps65217_set_bits(charger->tps, TPS65217_REG_CHGCONFIG1,
     89				TPS65217_CHGCONFIG1_CHG_EN,
     90				TPS65217_CHGCONFIG1_CHG_EN,
     91				TPS65217_PROTECT_NONE);
     92	if (ret) {
     93		dev_err(charger->dev,
     94			"%s: Error in writing CHG_EN in reg 0x%x: %d\n",
     95			__func__, TPS65217_REG_CHGCONFIG1, ret);
     96		return ret;
     97	}
     98
     99	charger->online = 1;
    100
    101	return 0;
    102}
    103
    104static int tps65217_charger_get_property(struct power_supply *psy,
    105					 enum power_supply_property psp,
    106					 union power_supply_propval *val)
    107{
    108	struct tps65217_charger *charger = power_supply_get_drvdata(psy);
    109
    110	if (psp == POWER_SUPPLY_PROP_ONLINE) {
    111		val->intval = charger->online;
    112		return 0;
    113	}
    114	return -EINVAL;
    115}
    116
    117static irqreturn_t tps65217_charger_irq(int irq, void *dev)
    118{
    119	int ret, val;
    120	struct tps65217_charger *charger = dev;
    121
    122	charger->prev_online = charger->online;
    123
    124	ret = tps65217_reg_read(charger->tps, TPS65217_REG_STATUS, &val);
    125	if (ret < 0) {
    126		dev_err(charger->dev, "%s: Error in reading reg 0x%x\n",
    127			__func__, TPS65217_REG_STATUS);
    128		return IRQ_HANDLED;
    129	}
    130
    131	dev_dbg(charger->dev, "%s: 0x%x\n", __func__, val);
    132
    133	/* check for charger status bit */
    134	if (val & CHARGER_STATUS_PRESENT) {
    135		ret = tps65217_enable_charging(charger);
    136		if (ret) {
    137			dev_err(charger->dev,
    138				"failed to enable charger: %d\n", ret);
    139			return IRQ_HANDLED;
    140		}
    141	} else {
    142		charger->online = 0;
    143	}
    144
    145	if (charger->prev_online != charger->online)
    146		power_supply_changed(charger->psy);
    147
    148	ret = tps65217_reg_read(charger->tps, TPS65217_REG_CHGCONFIG0, &val);
    149	if (ret < 0) {
    150		dev_err(charger->dev, "%s: Error in reading reg 0x%x\n",
    151			__func__, TPS65217_REG_CHGCONFIG0);
    152		return IRQ_HANDLED;
    153	}
    154
    155	if (val & TPS65217_CHGCONFIG0_ACTIVE)
    156		dev_dbg(charger->dev, "%s: charger is charging\n", __func__);
    157	else
    158		dev_dbg(charger->dev,
    159			"%s: charger is NOT charging\n", __func__);
    160
    161	return IRQ_HANDLED;
    162}
    163
    164static int tps65217_charger_poll_task(void *data)
    165{
    166	set_freezable();
    167
    168	while (!kthread_should_stop()) {
    169		schedule_timeout_interruptible(POLL_INTERVAL);
    170		try_to_freeze();
    171		tps65217_charger_irq(-1, data);
    172	}
    173	return 0;
    174}
    175
    176static const struct power_supply_desc tps65217_charger_desc = {
    177	.name			= "tps65217-charger",
    178	.type			= POWER_SUPPLY_TYPE_MAINS,
    179	.get_property		= tps65217_charger_get_property,
    180	.properties		= tps65217_charger_props,
    181	.num_properties		= ARRAY_SIZE(tps65217_charger_props),
    182};
    183
    184static int tps65217_charger_probe(struct platform_device *pdev)
    185{
    186	struct tps65217 *tps = dev_get_drvdata(pdev->dev.parent);
    187	struct tps65217_charger *charger;
    188	struct power_supply_config cfg = {};
    189	struct task_struct *poll_task;
    190	int irq[NUM_CHARGER_IRQS];
    191	int ret;
    192	int i;
    193
    194	charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL);
    195	if (!charger)
    196		return -ENOMEM;
    197
    198	platform_set_drvdata(pdev, charger);
    199	charger->tps = tps;
    200	charger->dev = &pdev->dev;
    201
    202	cfg.of_node = pdev->dev.of_node;
    203	cfg.drv_data = charger;
    204
    205	charger->psy = devm_power_supply_register(&pdev->dev,
    206						  &tps65217_charger_desc,
    207						  &cfg);
    208	if (IS_ERR(charger->psy)) {
    209		dev_err(&pdev->dev, "failed: power supply register\n");
    210		return PTR_ERR(charger->psy);
    211	}
    212
    213	irq[0] = platform_get_irq_byname(pdev, "USB");
    214	irq[1] = platform_get_irq_byname(pdev, "AC");
    215
    216	ret = tps65217_config_charger(charger);
    217	if (ret < 0) {
    218		dev_err(charger->dev, "charger config failed, err %d\n", ret);
    219		return ret;
    220	}
    221
    222	/* Create a polling thread if an interrupt is invalid */
    223	if (irq[0] < 0 || irq[1] < 0) {
    224		poll_task = kthread_run(tps65217_charger_poll_task,
    225					charger, "ktps65217charger");
    226		if (IS_ERR(poll_task)) {
    227			ret = PTR_ERR(poll_task);
    228			dev_err(charger->dev,
    229				"Unable to run kthread err %d\n", ret);
    230			return ret;
    231		}
    232
    233		charger->poll_task = poll_task;
    234		return 0;
    235	}
    236
    237	/* Create IRQ threads for charger interrupts */
    238	for (i = 0; i < NUM_CHARGER_IRQS; i++) {
    239		ret = devm_request_threaded_irq(&pdev->dev, irq[i], NULL,
    240						tps65217_charger_irq,
    241						IRQF_ONESHOT, "tps65217-charger",
    242						charger);
    243		if (ret) {
    244			dev_err(charger->dev,
    245				"Unable to register irq %d err %d\n", irq[i],
    246				ret);
    247			return ret;
    248		}
    249
    250		/* Check current state */
    251		tps65217_charger_irq(-1, charger);
    252	}
    253
    254	return 0;
    255}
    256
    257static int tps65217_charger_remove(struct platform_device *pdev)
    258{
    259	struct tps65217_charger *charger = platform_get_drvdata(pdev);
    260
    261	if (charger->poll_task)
    262		kthread_stop(charger->poll_task);
    263
    264	return 0;
    265}
    266
    267static const struct of_device_id tps65217_charger_match_table[] = {
    268	{ .compatible = "ti,tps65217-charger", },
    269	{ /* sentinel */ }
    270};
    271MODULE_DEVICE_TABLE(of, tps65217_charger_match_table);
    272
    273static struct platform_driver tps65217_charger_driver = {
    274	.probe	= tps65217_charger_probe,
    275	.remove = tps65217_charger_remove,
    276	.driver	= {
    277		.name	= "tps65217-charger",
    278		.of_match_table = of_match_ptr(tps65217_charger_match_table),
    279	},
    280
    281};
    282module_platform_driver(tps65217_charger_driver);
    283
    284MODULE_LICENSE("GPL v2");
    285MODULE_AUTHOR("Enric Balletbo Serra <enric.balletbo@collabora.com>");
    286MODULE_DESCRIPTION("TPS65217 battery charger driver");