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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power_supply_hwmon.c (9476B)


      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 *  power_supply_hwmon.c - power supply hwmon support.
      4 */
      5
      6#include <linux/err.h>
      7#include <linux/hwmon.h>
      8#include <linux/power_supply.h>
      9#include <linux/slab.h>
     10
     11struct power_supply_hwmon {
     12	struct power_supply *psy;
     13	unsigned long *props;
     14};
     15
     16static const char *const ps_temp_label[] = {
     17	"temp",
     18	"ambient temp",
     19};
     20
     21static int power_supply_hwmon_in_to_property(u32 attr)
     22{
     23	switch (attr) {
     24	case hwmon_in_average:
     25		return POWER_SUPPLY_PROP_VOLTAGE_AVG;
     26	case hwmon_in_min:
     27		return POWER_SUPPLY_PROP_VOLTAGE_MIN;
     28	case hwmon_in_max:
     29		return POWER_SUPPLY_PROP_VOLTAGE_MAX;
     30	case hwmon_in_input:
     31		return POWER_SUPPLY_PROP_VOLTAGE_NOW;
     32	default:
     33		return -EINVAL;
     34	}
     35}
     36
     37static int power_supply_hwmon_curr_to_property(u32 attr)
     38{
     39	switch (attr) {
     40	case hwmon_curr_average:
     41		return POWER_SUPPLY_PROP_CURRENT_AVG;
     42	case hwmon_curr_max:
     43		return POWER_SUPPLY_PROP_CURRENT_MAX;
     44	case hwmon_curr_input:
     45		return POWER_SUPPLY_PROP_CURRENT_NOW;
     46	default:
     47		return -EINVAL;
     48	}
     49}
     50
     51static int power_supply_hwmon_temp_to_property(u32 attr, int channel)
     52{
     53	if (channel) {
     54		switch (attr) {
     55		case hwmon_temp_input:
     56			return POWER_SUPPLY_PROP_TEMP_AMBIENT;
     57		case hwmon_temp_min_alarm:
     58			return POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MIN;
     59		case hwmon_temp_max_alarm:
     60			return POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MAX;
     61		default:
     62			break;
     63		}
     64	} else {
     65		switch (attr) {
     66		case hwmon_temp_input:
     67			return POWER_SUPPLY_PROP_TEMP;
     68		case hwmon_temp_max:
     69			return POWER_SUPPLY_PROP_TEMP_MAX;
     70		case hwmon_temp_min:
     71			return POWER_SUPPLY_PROP_TEMP_MIN;
     72		case hwmon_temp_min_alarm:
     73			return POWER_SUPPLY_PROP_TEMP_ALERT_MIN;
     74		case hwmon_temp_max_alarm:
     75			return POWER_SUPPLY_PROP_TEMP_ALERT_MAX;
     76		default:
     77			break;
     78		}
     79	}
     80
     81	return -EINVAL;
     82}
     83
     84static int
     85power_supply_hwmon_to_property(enum hwmon_sensor_types type,
     86			       u32 attr, int channel)
     87{
     88	switch (type) {
     89	case hwmon_in:
     90		return power_supply_hwmon_in_to_property(attr);
     91	case hwmon_curr:
     92		return power_supply_hwmon_curr_to_property(attr);
     93	case hwmon_temp:
     94		return power_supply_hwmon_temp_to_property(attr, channel);
     95	default:
     96		return -EINVAL;
     97	}
     98}
     99
    100static bool power_supply_hwmon_is_a_label(enum hwmon_sensor_types type,
    101					   u32 attr)
    102{
    103	return type == hwmon_temp && attr == hwmon_temp_label;
    104}
    105
    106struct hwmon_type_attr_list {
    107	const u32 *attrs;
    108	size_t n_attrs;
    109};
    110
    111static const u32 ps_temp_attrs[] = {
    112	hwmon_temp_input,
    113	hwmon_temp_min, hwmon_temp_max,
    114	hwmon_temp_min_alarm, hwmon_temp_max_alarm,
    115};
    116
    117static const struct hwmon_type_attr_list ps_type_attrs[hwmon_max] = {
    118	[hwmon_temp] = { ps_temp_attrs, ARRAY_SIZE(ps_temp_attrs) },
    119};
    120
    121static bool power_supply_hwmon_has_input(
    122	const struct power_supply_hwmon *psyhw,
    123	enum hwmon_sensor_types type, int channel)
    124{
    125	const struct hwmon_type_attr_list *attr_list = &ps_type_attrs[type];
    126	size_t i;
    127
    128	for (i = 0; i < attr_list->n_attrs; ++i) {
    129		int prop = power_supply_hwmon_to_property(type,
    130			attr_list->attrs[i], channel);
    131
    132		if (prop >= 0 && test_bit(prop, psyhw->props))
    133			return true;
    134	}
    135
    136	return false;
    137}
    138
    139static bool power_supply_hwmon_is_writable(enum hwmon_sensor_types type,
    140					   u32 attr)
    141{
    142	switch (type) {
    143	case hwmon_in:
    144		return attr == hwmon_in_min ||
    145		       attr == hwmon_in_max;
    146	case hwmon_curr:
    147		return attr == hwmon_curr_max;
    148	case hwmon_temp:
    149		return attr == hwmon_temp_max ||
    150		       attr == hwmon_temp_min ||
    151		       attr == hwmon_temp_min_alarm ||
    152		       attr == hwmon_temp_max_alarm;
    153	default:
    154		return false;
    155	}
    156}
    157
    158static umode_t power_supply_hwmon_is_visible(const void *data,
    159					     enum hwmon_sensor_types type,
    160					     u32 attr, int channel)
    161{
    162	const struct power_supply_hwmon *psyhw = data;
    163	int prop;
    164
    165	if (power_supply_hwmon_is_a_label(type, attr)) {
    166		if (power_supply_hwmon_has_input(psyhw, type, channel))
    167			return 0444;
    168		else
    169			return 0;
    170	}
    171
    172	prop = power_supply_hwmon_to_property(type, attr, channel);
    173	if (prop < 0 || !test_bit(prop, psyhw->props))
    174		return 0;
    175
    176	if (power_supply_property_is_writeable(psyhw->psy, prop) > 0 &&
    177	    power_supply_hwmon_is_writable(type, attr))
    178		return 0644;
    179
    180	return 0444;
    181}
    182
    183static int power_supply_hwmon_read_string(struct device *dev,
    184					  enum hwmon_sensor_types type,
    185					  u32 attr, int channel,
    186					  const char **str)
    187{
    188	switch (type) {
    189	case hwmon_temp:
    190		*str = ps_temp_label[channel];
    191		break;
    192	default:
    193		/* unreachable, but see:
    194		 * gcc bug #51513 [1] and clang bug #978 [2]
    195		 *
    196		 * [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=51513
    197		 * [2] https://github.com/ClangBuiltLinux/linux/issues/978
    198		 */
    199		break;
    200	}
    201
    202	return 0;
    203}
    204
    205static int
    206power_supply_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
    207			u32 attr, int channel, long *val)
    208{
    209	struct power_supply_hwmon *psyhw = dev_get_drvdata(dev);
    210	struct power_supply *psy = psyhw->psy;
    211	union power_supply_propval pspval;
    212	int ret, prop;
    213
    214	prop = power_supply_hwmon_to_property(type, attr, channel);
    215	if (prop < 0)
    216		return prop;
    217
    218	ret  = power_supply_get_property(psy, prop, &pspval);
    219	if (ret)
    220		return ret;
    221
    222	switch (type) {
    223	/*
    224	 * Both voltage and current is reported in units of
    225	 * microvolts/microamps, so we need to adjust it to
    226	 * milliamps(volts)
    227	 */
    228	case hwmon_curr:
    229	case hwmon_in:
    230		pspval.intval = DIV_ROUND_CLOSEST(pspval.intval, 1000);
    231		break;
    232	/*
    233	 * Temp needs to be converted from 1/10 C to milli-C
    234	 */
    235	case hwmon_temp:
    236		if (check_mul_overflow(pspval.intval, 100,
    237				       &pspval.intval))
    238			return -EOVERFLOW;
    239		break;
    240	default:
    241		return -EINVAL;
    242	}
    243
    244	*val = pspval.intval;
    245
    246	return 0;
    247}
    248
    249static int
    250power_supply_hwmon_write(struct device *dev, enum hwmon_sensor_types type,
    251			 u32 attr, int channel, long val)
    252{
    253	struct power_supply_hwmon *psyhw = dev_get_drvdata(dev);
    254	struct power_supply *psy = psyhw->psy;
    255	union power_supply_propval pspval;
    256	int prop;
    257
    258	prop = power_supply_hwmon_to_property(type, attr, channel);
    259	if (prop < 0)
    260		return prop;
    261
    262	pspval.intval = val;
    263
    264	switch (type) {
    265	/*
    266	 * Both voltage and current is reported in units of
    267	 * microvolts/microamps, so we need to adjust it to
    268	 * milliamps(volts)
    269	 */
    270	case hwmon_curr:
    271	case hwmon_in:
    272		if (check_mul_overflow(pspval.intval, 1000,
    273				       &pspval.intval))
    274			return -EOVERFLOW;
    275		break;
    276	/*
    277	 * Temp needs to be converted from 1/10 C to milli-C
    278	 */
    279	case hwmon_temp:
    280		pspval.intval = DIV_ROUND_CLOSEST(pspval.intval, 100);
    281		break;
    282	default:
    283		return -EINVAL;
    284	}
    285
    286	return power_supply_set_property(psy, prop, &pspval);
    287}
    288
    289static const struct hwmon_ops power_supply_hwmon_ops = {
    290	.is_visible	= power_supply_hwmon_is_visible,
    291	.read		= power_supply_hwmon_read,
    292	.write		= power_supply_hwmon_write,
    293	.read_string	= power_supply_hwmon_read_string,
    294};
    295
    296static const struct hwmon_channel_info *power_supply_hwmon_info[] = {
    297	HWMON_CHANNEL_INFO(temp,
    298			   HWMON_T_LABEL     |
    299			   HWMON_T_INPUT     |
    300			   HWMON_T_MAX       |
    301			   HWMON_T_MIN       |
    302			   HWMON_T_MIN_ALARM,
    303
    304			   HWMON_T_LABEL     |
    305			   HWMON_T_INPUT     |
    306			   HWMON_T_MIN_ALARM |
    307			   HWMON_T_MAX_ALARM),
    308
    309	HWMON_CHANNEL_INFO(curr,
    310			   HWMON_C_AVERAGE |
    311			   HWMON_C_MAX     |
    312			   HWMON_C_INPUT),
    313
    314	HWMON_CHANNEL_INFO(in,
    315			   HWMON_I_AVERAGE |
    316			   HWMON_I_MIN     |
    317			   HWMON_I_MAX     |
    318			   HWMON_I_INPUT),
    319	NULL
    320};
    321
    322static const struct hwmon_chip_info power_supply_hwmon_chip_info = {
    323	.ops = &power_supply_hwmon_ops,
    324	.info = power_supply_hwmon_info,
    325};
    326
    327int power_supply_add_hwmon_sysfs(struct power_supply *psy)
    328{
    329	const struct power_supply_desc *desc = psy->desc;
    330	struct power_supply_hwmon *psyhw;
    331	struct device *dev = &psy->dev;
    332	struct device *hwmon;
    333	int ret, i;
    334	const char *name;
    335
    336	if (!devres_open_group(dev, power_supply_add_hwmon_sysfs,
    337			       GFP_KERNEL))
    338		return -ENOMEM;
    339
    340	psyhw = devm_kzalloc(dev, sizeof(*psyhw), GFP_KERNEL);
    341	if (!psyhw) {
    342		ret = -ENOMEM;
    343		goto error;
    344	}
    345
    346	psyhw->psy = psy;
    347	psyhw->props = devm_bitmap_zalloc(dev,
    348					  POWER_SUPPLY_PROP_TIME_TO_FULL_AVG + 1,
    349					  GFP_KERNEL);
    350	if (!psyhw->props) {
    351		ret = -ENOMEM;
    352		goto error;
    353	}
    354
    355	for (i = 0; i < desc->num_properties; i++) {
    356		const enum power_supply_property prop = desc->properties[i];
    357
    358		switch (prop) {
    359		case POWER_SUPPLY_PROP_CURRENT_AVG:
    360		case POWER_SUPPLY_PROP_CURRENT_MAX:
    361		case POWER_SUPPLY_PROP_CURRENT_NOW:
    362		case POWER_SUPPLY_PROP_TEMP:
    363		case POWER_SUPPLY_PROP_TEMP_MAX:
    364		case POWER_SUPPLY_PROP_TEMP_MIN:
    365		case POWER_SUPPLY_PROP_TEMP_ALERT_MIN:
    366		case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
    367		case POWER_SUPPLY_PROP_TEMP_AMBIENT:
    368		case POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MIN:
    369		case POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MAX:
    370		case POWER_SUPPLY_PROP_VOLTAGE_AVG:
    371		case POWER_SUPPLY_PROP_VOLTAGE_MIN:
    372		case POWER_SUPPLY_PROP_VOLTAGE_MAX:
    373		case POWER_SUPPLY_PROP_VOLTAGE_NOW:
    374			set_bit(prop, psyhw->props);
    375			break;
    376		default:
    377			break;
    378		}
    379	}
    380
    381	name = psy->desc->name;
    382	if (strchr(name, '-')) {
    383		char *new_name;
    384
    385		new_name = devm_kstrdup(dev, name, GFP_KERNEL);
    386		if (!new_name) {
    387			ret = -ENOMEM;
    388			goto error;
    389		}
    390		strreplace(new_name, '-', '_');
    391		name = new_name;
    392	}
    393	hwmon = devm_hwmon_device_register_with_info(dev, name,
    394						psyhw,
    395						&power_supply_hwmon_chip_info,
    396						NULL);
    397	ret = PTR_ERR_OR_ZERO(hwmon);
    398	if (ret)
    399		goto error;
    400
    401	devres_close_group(dev, power_supply_add_hwmon_sysfs);
    402	return 0;
    403error:
    404	devres_release_group(dev, NULL);
    405	return ret;
    406}
    407
    408void power_supply_remove_hwmon_sysfs(struct power_supply *psy)
    409{
    410	devres_release_group(&psy->dev, power_supply_add_hwmon_sysfs);
    411}