19bc289b8SHenning Schild // SPDX-License-Identifier: GPL-2.0
29bc289b8SHenning Schild /*
39bc289b8SHenning Schild * Siemens SIMATIC IPC driver for CMOS battery monitoring
49bc289b8SHenning Schild *
59bc289b8SHenning Schild * Copyright (c) Siemens AG, 2023
69bc289b8SHenning Schild *
79bc289b8SHenning Schild * Authors:
89bc289b8SHenning Schild * Gerd Haeussler <gerd.haeussler.ext@siemens.com>
99bc289b8SHenning Schild * Henning Schild <henning.schild@siemens.com>
109bc289b8SHenning Schild */
119bc289b8SHenning Schild
129bc289b8SHenning Schild #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
139bc289b8SHenning Schild
149bc289b8SHenning Schild #include <linux/delay.h>
159bc289b8SHenning Schild #include <linux/io.h>
169bc289b8SHenning Schild #include <linux/ioport.h>
179bc289b8SHenning Schild #include <linux/gpio/machine.h>
189bc289b8SHenning Schild #include <linux/gpio/consumer.h>
199bc289b8SHenning Schild #include <linux/hwmon.h>
209bc289b8SHenning Schild #include <linux/hwmon-sysfs.h>
219bc289b8SHenning Schild #include <linux/jiffies.h>
229bc289b8SHenning Schild #include <linux/kernel.h>
239bc289b8SHenning Schild #include <linux/module.h>
249bc289b8SHenning Schild #include <linux/platform_device.h>
259bc289b8SHenning Schild #include <linux/platform_data/x86/simatic-ipc-base.h>
269bc289b8SHenning Schild #include <linux/sizes.h>
279bc289b8SHenning Schild
289bc289b8SHenning Schild #include "simatic-ipc-batt.h"
299bc289b8SHenning Schild
309bc289b8SHenning Schild #define BATT_DELAY_MS (1000 * 60 * 60 * 24) /* 24 h delay */
319bc289b8SHenning Schild
329bc289b8SHenning Schild #define SIMATIC_IPC_BATT_LEVEL_FULL 3000
339bc289b8SHenning Schild #define SIMATIC_IPC_BATT_LEVEL_CRIT 2750
349bc289b8SHenning Schild #define SIMATIC_IPC_BATT_LEVEL_EMPTY 0
359bc289b8SHenning Schild
369bc289b8SHenning Schild static struct simatic_ipc_batt {
379bc289b8SHenning Schild u8 devmode;
389bc289b8SHenning Schild long current_state;
399bc289b8SHenning Schild struct gpio_desc *gpios[3];
409bc289b8SHenning Schild unsigned long last_updated_jiffies;
419bc289b8SHenning Schild } priv;
429bc289b8SHenning Schild
simatic_ipc_batt_read_gpio(void)439bc289b8SHenning Schild static long simatic_ipc_batt_read_gpio(void)
449bc289b8SHenning Schild {
459bc289b8SHenning Schild long r = SIMATIC_IPC_BATT_LEVEL_FULL;
469bc289b8SHenning Schild
479bc289b8SHenning Schild if (priv.gpios[2]) {
489bc289b8SHenning Schild gpiod_set_value(priv.gpios[2], 1);
499bc289b8SHenning Schild msleep(150);
509bc289b8SHenning Schild }
519bc289b8SHenning Schild
529bc289b8SHenning Schild if (gpiod_get_value_cansleep(priv.gpios[0]))
539bc289b8SHenning Schild r = SIMATIC_IPC_BATT_LEVEL_EMPTY;
549bc289b8SHenning Schild else if (gpiod_get_value_cansleep(priv.gpios[1]))
559bc289b8SHenning Schild r = SIMATIC_IPC_BATT_LEVEL_CRIT;
569bc289b8SHenning Schild
579bc289b8SHenning Schild if (priv.gpios[2])
589bc289b8SHenning Schild gpiod_set_value(priv.gpios[2], 0);
599bc289b8SHenning Schild
609bc289b8SHenning Schild return r;
619bc289b8SHenning Schild }
629bc289b8SHenning Schild
639bc289b8SHenning Schild #define SIMATIC_IPC_BATT_PORT_BASE 0x404D
649bc289b8SHenning Schild static struct resource simatic_ipc_batt_io_res =
659bc289b8SHenning Schild DEFINE_RES_IO_NAMED(SIMATIC_IPC_BATT_PORT_BASE, SZ_1, KBUILD_MODNAME);
669bc289b8SHenning Schild
simatic_ipc_batt_read_io(struct device * dev)679bc289b8SHenning Schild static long simatic_ipc_batt_read_io(struct device *dev)
689bc289b8SHenning Schild {
699bc289b8SHenning Schild long r = SIMATIC_IPC_BATT_LEVEL_FULL;
709bc289b8SHenning Schild struct resource *res = &simatic_ipc_batt_io_res;
719bc289b8SHenning Schild u8 val;
729bc289b8SHenning Schild
739bc289b8SHenning Schild if (!request_muxed_region(res->start, resource_size(res), res->name)) {
749bc289b8SHenning Schild dev_err(dev, "Unable to register IO resource at %pR\n", res);
759bc289b8SHenning Schild return -EBUSY;
769bc289b8SHenning Schild }
779bc289b8SHenning Schild
789bc289b8SHenning Schild val = inb(SIMATIC_IPC_BATT_PORT_BASE);
799bc289b8SHenning Schild release_region(simatic_ipc_batt_io_res.start, resource_size(&simatic_ipc_batt_io_res));
809bc289b8SHenning Schild
819bc289b8SHenning Schild if (val & (1 << 7))
829bc289b8SHenning Schild r = SIMATIC_IPC_BATT_LEVEL_EMPTY;
839bc289b8SHenning Schild else if (val & (1 << 6))
849bc289b8SHenning Schild r = SIMATIC_IPC_BATT_LEVEL_CRIT;
859bc289b8SHenning Schild
869bc289b8SHenning Schild return r;
879bc289b8SHenning Schild }
889bc289b8SHenning Schild
simatic_ipc_batt_read_value(struct device * dev)899bc289b8SHenning Schild static long simatic_ipc_batt_read_value(struct device *dev)
909bc289b8SHenning Schild {
919bc289b8SHenning Schild unsigned long next_update;
929bc289b8SHenning Schild
939bc289b8SHenning Schild next_update = priv.last_updated_jiffies + msecs_to_jiffies(BATT_DELAY_MS);
949bc289b8SHenning Schild if (time_after(jiffies, next_update) || !priv.last_updated_jiffies) {
95d0563dd3Sxingtong.wu if (priv.devmode == SIMATIC_IPC_DEVICE_227E)
969bc289b8SHenning Schild priv.current_state = simatic_ipc_batt_read_io(dev);
97d0563dd3Sxingtong.wu else
98d0563dd3Sxingtong.wu priv.current_state = simatic_ipc_batt_read_gpio();
99d0563dd3Sxingtong.wu
1009bc289b8SHenning Schild priv.last_updated_jiffies = jiffies;
1019bc289b8SHenning Schild if (priv.current_state < SIMATIC_IPC_BATT_LEVEL_FULL)
102d0563dd3Sxingtong.wu dev_warn(dev, "CMOS battery needs to be replaced.\n");
1039bc289b8SHenning Schild }
1049bc289b8SHenning Schild
1059bc289b8SHenning Schild return priv.current_state;
1069bc289b8SHenning Schild }
1079bc289b8SHenning Schild
simatic_ipc_batt_read(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long * val)1089bc289b8SHenning Schild static int simatic_ipc_batt_read(struct device *dev, enum hwmon_sensor_types type,
1099bc289b8SHenning Schild u32 attr, int channel, long *val)
1109bc289b8SHenning Schild {
1119bc289b8SHenning Schild switch (attr) {
1129bc289b8SHenning Schild case hwmon_in_input:
1139bc289b8SHenning Schild *val = simatic_ipc_batt_read_value(dev);
1149bc289b8SHenning Schild break;
1159bc289b8SHenning Schild case hwmon_in_lcrit:
1169bc289b8SHenning Schild *val = SIMATIC_IPC_BATT_LEVEL_CRIT;
1179bc289b8SHenning Schild break;
1189bc289b8SHenning Schild default:
1199bc289b8SHenning Schild return -EOPNOTSUPP;
1209bc289b8SHenning Schild }
1219bc289b8SHenning Schild
1229bc289b8SHenning Schild return 0;
1239bc289b8SHenning Schild }
1249bc289b8SHenning Schild
simatic_ipc_batt_is_visible(const void * data,enum hwmon_sensor_types type,u32 attr,int channel)1259bc289b8SHenning Schild static umode_t simatic_ipc_batt_is_visible(const void *data, enum hwmon_sensor_types type,
1269bc289b8SHenning Schild u32 attr, int channel)
1279bc289b8SHenning Schild {
1289bc289b8SHenning Schild if (attr == hwmon_in_input || attr == hwmon_in_lcrit)
1299bc289b8SHenning Schild return 0444;
1309bc289b8SHenning Schild
1319bc289b8SHenning Schild return 0;
1329bc289b8SHenning Schild }
1339bc289b8SHenning Schild
1349bc289b8SHenning Schild static const struct hwmon_ops simatic_ipc_batt_ops = {
1359bc289b8SHenning Schild .is_visible = simatic_ipc_batt_is_visible,
1369bc289b8SHenning Schild .read = simatic_ipc_batt_read,
1379bc289b8SHenning Schild };
1389bc289b8SHenning Schild
1399bc289b8SHenning Schild static const struct hwmon_channel_info *simatic_ipc_batt_info[] = {
1409bc289b8SHenning Schild HWMON_CHANNEL_INFO(in, HWMON_I_INPUT | HWMON_I_LCRIT),
1419bc289b8SHenning Schild NULL
1429bc289b8SHenning Schild };
1439bc289b8SHenning Schild
1449bc289b8SHenning Schild static const struct hwmon_chip_info simatic_ipc_batt_chip_info = {
1459bc289b8SHenning Schild .ops = &simatic_ipc_batt_ops,
1469bc289b8SHenning Schild .info = simatic_ipc_batt_info,
1479bc289b8SHenning Schild };
1489bc289b8SHenning Schild
simatic_ipc_batt_remove(struct platform_device * pdev,struct gpiod_lookup_table * table)1499bc289b8SHenning Schild int simatic_ipc_batt_remove(struct platform_device *pdev, struct gpiod_lookup_table *table)
1509bc289b8SHenning Schild {
1519bc289b8SHenning Schild gpiod_remove_lookup_table(table);
1529bc289b8SHenning Schild return 0;
1539bc289b8SHenning Schild }
1549bc289b8SHenning Schild EXPORT_SYMBOL_GPL(simatic_ipc_batt_remove);
1559bc289b8SHenning Schild
simatic_ipc_batt_probe(struct platform_device * pdev,struct gpiod_lookup_table * table)1569bc289b8SHenning Schild int simatic_ipc_batt_probe(struct platform_device *pdev, struct gpiod_lookup_table *table)
1579bc289b8SHenning Schild {
1589bc289b8SHenning Schild struct simatic_ipc_platform *plat;
1599bc289b8SHenning Schild struct device *dev = &pdev->dev;
1609bc289b8SHenning Schild struct device *hwmon_dev;
161d0563dd3Sxingtong.wu unsigned long flags;
1629bc289b8SHenning Schild int err;
1639bc289b8SHenning Schild
1649bc289b8SHenning Schild plat = pdev->dev.platform_data;
1659bc289b8SHenning Schild priv.devmode = plat->devmode;
1669bc289b8SHenning Schild
1679bc289b8SHenning Schild switch (priv.devmode) {
1689bc289b8SHenning Schild case SIMATIC_IPC_DEVICE_127E:
1699bc289b8SHenning Schild case SIMATIC_IPC_DEVICE_227G:
1709bc289b8SHenning Schild case SIMATIC_IPC_DEVICE_BX_39A:
1719bc289b8SHenning Schild case SIMATIC_IPC_DEVICE_BX_21A:
172c56beff2Sxingtong.wu case SIMATIC_IPC_DEVICE_BX_59A:
1739bc289b8SHenning Schild table->dev_id = dev_name(dev);
1749bc289b8SHenning Schild gpiod_add_lookup_table(table);
1759bc289b8SHenning Schild break;
1769bc289b8SHenning Schild case SIMATIC_IPC_DEVICE_227E:
1779bc289b8SHenning Schild goto nogpio;
1789bc289b8SHenning Schild default:
1799bc289b8SHenning Schild return -ENODEV;
1809bc289b8SHenning Schild }
1819bc289b8SHenning Schild
1829bc289b8SHenning Schild priv.gpios[0] = devm_gpiod_get_index(dev, "CMOSBattery empty", 0, GPIOD_IN);
1839bc289b8SHenning Schild if (IS_ERR(priv.gpios[0])) {
1849bc289b8SHenning Schild err = PTR_ERR(priv.gpios[0]);
1859bc289b8SHenning Schild priv.gpios[0] = NULL;
1869bc289b8SHenning Schild goto out;
1879bc289b8SHenning Schild }
1889bc289b8SHenning Schild priv.gpios[1] = devm_gpiod_get_index(dev, "CMOSBattery low", 1, GPIOD_IN);
1899bc289b8SHenning Schild if (IS_ERR(priv.gpios[1])) {
1909bc289b8SHenning Schild err = PTR_ERR(priv.gpios[1]);
1919bc289b8SHenning Schild priv.gpios[1] = NULL;
1929bc289b8SHenning Schild goto out;
1939bc289b8SHenning Schild }
1949bc289b8SHenning Schild
1959bc289b8SHenning Schild if (table->table[2].key) {
196d0563dd3Sxingtong.wu flags = GPIOD_OUT_HIGH;
197*7abf253aSxingtong.wu if (priv.devmode == SIMATIC_IPC_DEVICE_BX_21A ||
198*7abf253aSxingtong.wu priv.devmode == SIMATIC_IPC_DEVICE_BX_59A)
199d0563dd3Sxingtong.wu flags = GPIOD_OUT_LOW;
200d0563dd3Sxingtong.wu priv.gpios[2] = devm_gpiod_get_index(dev, "CMOSBattery meter", 2, flags);
2019bc289b8SHenning Schild if (IS_ERR(priv.gpios[2])) {
202e5d5ffa4SYang Yingliang err = PTR_ERR(priv.gpios[2]);
2039bc289b8SHenning Schild priv.gpios[2] = NULL;
2049bc289b8SHenning Schild goto out;
2059bc289b8SHenning Schild }
2069bc289b8SHenning Schild } else {
2079bc289b8SHenning Schild priv.gpios[2] = NULL;
2089bc289b8SHenning Schild }
2099bc289b8SHenning Schild
2109bc289b8SHenning Schild nogpio:
2119bc289b8SHenning Schild hwmon_dev = devm_hwmon_device_register_with_info(dev, KBUILD_MODNAME,
2129bc289b8SHenning Schild &priv,
2139bc289b8SHenning Schild &simatic_ipc_batt_chip_info,
2149bc289b8SHenning Schild NULL);
2159bc289b8SHenning Schild if (IS_ERR(hwmon_dev)) {
2169bc289b8SHenning Schild err = PTR_ERR(hwmon_dev);
2179bc289b8SHenning Schild goto out;
2189bc289b8SHenning Schild }
2199bc289b8SHenning Schild
2209bc289b8SHenning Schild /* warn about aging battery even if userspace never reads hwmon */
2219bc289b8SHenning Schild simatic_ipc_batt_read_value(dev);
2229bc289b8SHenning Schild
2239bc289b8SHenning Schild return 0;
2249bc289b8SHenning Schild out:
2259bc289b8SHenning Schild simatic_ipc_batt_remove(pdev, table);
2269bc289b8SHenning Schild
2279bc289b8SHenning Schild return err;
2289bc289b8SHenning Schild }
2299bc289b8SHenning Schild EXPORT_SYMBOL_GPL(simatic_ipc_batt_probe);
2309bc289b8SHenning Schild
simatic_ipc_batt_io_remove(struct platform_device * pdev)2319bc289b8SHenning Schild static int simatic_ipc_batt_io_remove(struct platform_device *pdev)
2329bc289b8SHenning Schild {
2339bc289b8SHenning Schild return simatic_ipc_batt_remove(pdev, NULL);
2349bc289b8SHenning Schild }
2359bc289b8SHenning Schild
simatic_ipc_batt_io_probe(struct platform_device * pdev)2369bc289b8SHenning Schild static int simatic_ipc_batt_io_probe(struct platform_device *pdev)
2379bc289b8SHenning Schild {
2389bc289b8SHenning Schild return simatic_ipc_batt_probe(pdev, NULL);
2399bc289b8SHenning Schild }
2409bc289b8SHenning Schild
2419bc289b8SHenning Schild static struct platform_driver simatic_ipc_batt_driver = {
2429bc289b8SHenning Schild .probe = simatic_ipc_batt_io_probe,
2439bc289b8SHenning Schild .remove = simatic_ipc_batt_io_remove,
2449bc289b8SHenning Schild .driver = {
2459bc289b8SHenning Schild .name = KBUILD_MODNAME,
2469bc289b8SHenning Schild },
2479bc289b8SHenning Schild };
2489bc289b8SHenning Schild
2499bc289b8SHenning Schild module_platform_driver(simatic_ipc_batt_driver);
2509bc289b8SHenning Schild
2519bc289b8SHenning Schild MODULE_LICENSE("GPL");
2529bc289b8SHenning Schild MODULE_ALIAS("platform:" KBUILD_MODNAME);
2539bc289b8SHenning Schild MODULE_AUTHOR("Henning Schild <henning.schild@siemens.com>");
254