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Diffstat (limited to 'drivers/platform/surface/surface3_power.c')
-rw-r--r--drivers/platform/surface/surface3_power.c587
1 files changed, 587 insertions, 0 deletions
diff --git a/drivers/platform/surface/surface3_power.c b/drivers/platform/surface/surface3_power.c
new file mode 100644
index 000000000..73961a24c
--- /dev/null
+++ b/drivers/platform/surface/surface3_power.c
@@ -0,0 +1,587 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Supports for the power IC on the Surface 3 tablet.
+ *
+ * (C) Copyright 2016-2018 Red Hat, Inc
+ * (C) Copyright 2016-2018 Benjamin Tissoires <benjamin.tissoires@gmail.com>
+ * (C) Copyright 2016 Stephen Just <stephenjust@gmail.com>
+ *
+ * This driver has been reverse-engineered by parsing the DSDT of the Surface 3
+ * and looking at the registers of the chips.
+ *
+ * The DSDT allowed to find out that:
+ * - the driver is required for the ACPI BAT0 device to communicate to the chip
+ * through an operation region.
+ * - the various defines for the operation region functions to communicate with
+ * this driver
+ * - the DSM 3f99e367-6220-4955-8b0f-06ef2ae79412 allows to trigger ACPI
+ * events to BAT0 (the code is all available in the DSDT).
+ *
+ * Further findings regarding the 2 chips declared in the MSHW0011 are:
+ * - there are 2 chips declared:
+ * . 0x22 seems to control the ADP1 line status (and probably the charger)
+ * . 0x55 controls the battery directly
+ * - the battery chip uses a SMBus protocol (using plain SMBus allows non
+ * destructive commands):
+ * . the commands/registers used are in the range 0x00..0x7F
+ * . if bit 8 (0x80) is set in the SMBus command, the returned value is the
+ * same as when it is not set. There is a high chance this bit is the
+ * read/write
+ * . the various registers semantic as been deduced by observing the register
+ * dumps.
+ */
+
+#include <linux/acpi.h>
+#include <linux/bits.h>
+#include <linux/freezer.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/uuid.h>
+#include <asm/unaligned.h>
+
+#define SURFACE_3_POLL_INTERVAL (2 * HZ)
+#define SURFACE_3_STRLEN 10
+
+struct mshw0011_data {
+ struct i2c_client *adp1;
+ struct i2c_client *bat0;
+ unsigned short notify_mask;
+ struct task_struct *poll_task;
+ bool kthread_running;
+
+ bool charging;
+ bool bat_charging;
+ u8 trip_point;
+ s32 full_capacity;
+};
+
+struct mshw0011_handler_data {
+ struct acpi_connection_info info;
+ struct i2c_client *client;
+};
+
+struct bix {
+ u32 revision;
+ u32 power_unit;
+ u32 design_capacity;
+ u32 last_full_charg_capacity;
+ u32 battery_technology;
+ u32 design_voltage;
+ u32 design_capacity_of_warning;
+ u32 design_capacity_of_low;
+ u32 cycle_count;
+ u32 measurement_accuracy;
+ u32 max_sampling_time;
+ u32 min_sampling_time;
+ u32 max_average_interval;
+ u32 min_average_interval;
+ u32 battery_capacity_granularity_1;
+ u32 battery_capacity_granularity_2;
+ char model[SURFACE_3_STRLEN];
+ char serial[SURFACE_3_STRLEN];
+ char type[SURFACE_3_STRLEN];
+ char OEM[SURFACE_3_STRLEN];
+} __packed;
+
+struct bst {
+ u32 battery_state;
+ s32 battery_present_rate;
+ u32 battery_remaining_capacity;
+ u32 battery_present_voltage;
+} __packed;
+
+struct gsb_command {
+ u8 arg0;
+ u8 arg1;
+ u8 arg2;
+} __packed;
+
+struct gsb_buffer {
+ u8 status;
+ u8 len;
+ u8 ret;
+ union {
+ struct gsb_command cmd;
+ struct bst bst;
+ struct bix bix;
+ } __packed;
+} __packed;
+
+#define ACPI_BATTERY_STATE_DISCHARGING BIT(0)
+#define ACPI_BATTERY_STATE_CHARGING BIT(1)
+#define ACPI_BATTERY_STATE_CRITICAL BIT(2)
+
+#define MSHW0011_CMD_DEST_BAT0 0x01
+#define MSHW0011_CMD_DEST_ADP1 0x03
+
+#define MSHW0011_CMD_BAT0_STA 0x01
+#define MSHW0011_CMD_BAT0_BIX 0x02
+#define MSHW0011_CMD_BAT0_BCT 0x03
+#define MSHW0011_CMD_BAT0_BTM 0x04
+#define MSHW0011_CMD_BAT0_BST 0x05
+#define MSHW0011_CMD_BAT0_BTP 0x06
+#define MSHW0011_CMD_ADP1_PSR 0x07
+#define MSHW0011_CMD_BAT0_PSOC 0x09
+#define MSHW0011_CMD_BAT0_PMAX 0x0a
+#define MSHW0011_CMD_BAT0_PSRC 0x0b
+#define MSHW0011_CMD_BAT0_CHGI 0x0c
+#define MSHW0011_CMD_BAT0_ARTG 0x0d
+
+#define MSHW0011_NOTIFY_GET_VERSION 0x00
+#define MSHW0011_NOTIFY_ADP1 0x01
+#define MSHW0011_NOTIFY_BAT0_BST 0x02
+#define MSHW0011_NOTIFY_BAT0_BIX 0x05
+
+#define MSHW0011_ADP1_REG_PSR 0x04
+
+#define MSHW0011_BAT0_REG_CAPACITY 0x0c
+#define MSHW0011_BAT0_REG_FULL_CHG_CAPACITY 0x0e
+#define MSHW0011_BAT0_REG_DESIGN_CAPACITY 0x40
+#define MSHW0011_BAT0_REG_VOLTAGE 0x08
+#define MSHW0011_BAT0_REG_RATE 0x14
+#define MSHW0011_BAT0_REG_OEM 0x45
+#define MSHW0011_BAT0_REG_TYPE 0x4e
+#define MSHW0011_BAT0_REG_SERIAL_NO 0x56
+#define MSHW0011_BAT0_REG_CYCLE_CNT 0x6e
+
+#define MSHW0011_EV_2_5_MASK GENMASK(8, 0)
+
+/* 3f99e367-6220-4955-8b0f-06ef2ae79412 */
+static const guid_t mshw0011_guid =
+ GUID_INIT(0x3F99E367, 0x6220, 0x4955, 0x8B, 0x0F, 0x06, 0xEF,
+ 0x2A, 0xE7, 0x94, 0x12);
+
+static int
+mshw0011_notify(struct mshw0011_data *cdata, u8 arg1, u8 arg2,
+ unsigned int *ret_value)
+{
+ union acpi_object *obj;
+ acpi_handle handle;
+ unsigned int i;
+
+ handle = ACPI_HANDLE(&cdata->adp1->dev);
+ if (!handle)
+ return -ENODEV;
+
+ obj = acpi_evaluate_dsm_typed(handle, &mshw0011_guid, arg1, arg2, NULL,
+ ACPI_TYPE_BUFFER);
+ if (!obj) {
+ dev_err(&cdata->adp1->dev, "device _DSM execution failed\n");
+ return -ENODEV;
+ }
+
+ *ret_value = 0;
+ for (i = 0; i < obj->buffer.length; i++)
+ *ret_value |= obj->buffer.pointer[i] << (i * 8);
+
+ ACPI_FREE(obj);
+ return 0;
+}
+
+static const struct bix default_bix = {
+ .revision = 0x00,
+ .power_unit = 0x01,
+ .design_capacity = 0x1dca,
+ .last_full_charg_capacity = 0x1dca,
+ .battery_technology = 0x01,
+ .design_voltage = 0x10df,
+ .design_capacity_of_warning = 0x8f,
+ .design_capacity_of_low = 0x47,
+ .cycle_count = 0xffffffff,
+ .measurement_accuracy = 0x00015f90,
+ .max_sampling_time = 0x03e8,
+ .min_sampling_time = 0x03e8,
+ .max_average_interval = 0x03e8,
+ .min_average_interval = 0x03e8,
+ .battery_capacity_granularity_1 = 0x45,
+ .battery_capacity_granularity_2 = 0x11,
+ .model = "P11G8M",
+ .serial = "",
+ .type = "LION",
+ .OEM = "",
+};
+
+static int mshw0011_bix(struct mshw0011_data *cdata, struct bix *bix)
+{
+ struct i2c_client *client = cdata->bat0;
+ char buf[SURFACE_3_STRLEN];
+ int ret;
+
+ *bix = default_bix;
+
+ /* get design capacity */
+ ret = i2c_smbus_read_word_data(client,
+ MSHW0011_BAT0_REG_DESIGN_CAPACITY);
+ if (ret < 0) {
+ dev_err(&client->dev, "Error reading design capacity: %d\n",
+ ret);
+ return ret;
+ }
+ bix->design_capacity = ret;
+
+ /* get last full charge capacity */
+ ret = i2c_smbus_read_word_data(client,
+ MSHW0011_BAT0_REG_FULL_CHG_CAPACITY);
+ if (ret < 0) {
+ dev_err(&client->dev,
+ "Error reading last full charge capacity: %d\n", ret);
+ return ret;
+ }
+ bix->last_full_charg_capacity = ret;
+
+ /*
+ * Get serial number, on some devices (with unofficial replacement
+ * battery?) reading any of the serial number range addresses gets
+ * nacked in this case just leave the serial number empty.
+ */
+ ret = i2c_smbus_read_i2c_block_data(client, MSHW0011_BAT0_REG_SERIAL_NO,
+ sizeof(buf), buf);
+ if (ret == -EREMOTEIO) {
+ /* no serial number available */
+ } else if (ret != sizeof(buf)) {
+ dev_err(&client->dev, "Error reading serial no: %d\n", ret);
+ return ret;
+ } else {
+ snprintf(bix->serial, ARRAY_SIZE(bix->serial), "%3pE%6pE", buf + 7, buf);
+ }
+
+ /* get cycle count */
+ ret = i2c_smbus_read_word_data(client, MSHW0011_BAT0_REG_CYCLE_CNT);
+ if (ret < 0) {
+ dev_err(&client->dev, "Error reading cycle count: %d\n", ret);
+ return ret;
+ }
+ bix->cycle_count = ret;
+
+ /* get OEM name */
+ ret = i2c_smbus_read_i2c_block_data(client, MSHW0011_BAT0_REG_OEM,
+ 4, buf);
+ if (ret != 4) {
+ dev_err(&client->dev, "Error reading cycle count: %d\n", ret);
+ return ret;
+ }
+ snprintf(bix->OEM, ARRAY_SIZE(bix->OEM), "%3pE", buf);
+
+ return 0;
+}
+
+static int mshw0011_bst(struct mshw0011_data *cdata, struct bst *bst)
+{
+ struct i2c_client *client = cdata->bat0;
+ int rate, capacity, voltage, state;
+ s16 tmp;
+
+ rate = i2c_smbus_read_word_data(client, MSHW0011_BAT0_REG_RATE);
+ if (rate < 0)
+ return rate;
+
+ capacity = i2c_smbus_read_word_data(client, MSHW0011_BAT0_REG_CAPACITY);
+ if (capacity < 0)
+ return capacity;
+
+ voltage = i2c_smbus_read_word_data(client, MSHW0011_BAT0_REG_VOLTAGE);
+ if (voltage < 0)
+ return voltage;
+
+ tmp = rate;
+ bst->battery_present_rate = abs((s32)tmp);
+
+ state = 0;
+ if ((s32) tmp > 0)
+ state |= ACPI_BATTERY_STATE_CHARGING;
+ else if ((s32) tmp < 0)
+ state |= ACPI_BATTERY_STATE_DISCHARGING;
+ bst->battery_state = state;
+
+ bst->battery_remaining_capacity = capacity;
+ bst->battery_present_voltage = voltage;
+
+ return 0;
+}
+
+static int mshw0011_adp_psr(struct mshw0011_data *cdata)
+{
+ return i2c_smbus_read_byte_data(cdata->adp1, MSHW0011_ADP1_REG_PSR);
+}
+
+static int mshw0011_isr(struct mshw0011_data *cdata)
+{
+ struct bst bst;
+ struct bix bix;
+ int ret;
+ bool status, bat_status;
+
+ ret = mshw0011_adp_psr(cdata);
+ if (ret < 0)
+ return ret;
+
+ status = ret;
+ if (status != cdata->charging)
+ mshw0011_notify(cdata, cdata->notify_mask,
+ MSHW0011_NOTIFY_ADP1, &ret);
+
+ cdata->charging = status;
+
+ ret = mshw0011_bst(cdata, &bst);
+ if (ret < 0)
+ return ret;
+
+ bat_status = bst.battery_state;
+ if (bat_status != cdata->bat_charging)
+ mshw0011_notify(cdata, cdata->notify_mask,
+ MSHW0011_NOTIFY_BAT0_BST, &ret);
+
+ cdata->bat_charging = bat_status;
+
+ ret = mshw0011_bix(cdata, &bix);
+ if (ret < 0)
+ return ret;
+
+ if (bix.last_full_charg_capacity != cdata->full_capacity)
+ mshw0011_notify(cdata, cdata->notify_mask,
+ MSHW0011_NOTIFY_BAT0_BIX, &ret);
+
+ cdata->full_capacity = bix.last_full_charg_capacity;
+
+ return 0;
+}
+
+static int mshw0011_poll_task(void *data)
+{
+ struct mshw0011_data *cdata = data;
+ int ret = 0;
+
+ cdata->kthread_running = true;
+
+ set_freezable();
+
+ while (!kthread_should_stop()) {
+ schedule_timeout_interruptible(SURFACE_3_POLL_INTERVAL);
+ try_to_freeze();
+ ret = mshw0011_isr(data);
+ if (ret)
+ break;
+ }
+
+ cdata->kthread_running = false;
+ return ret;
+}
+
+static acpi_status
+mshw0011_space_handler(u32 function, acpi_physical_address command,
+ u32 bits, u64 *value64,
+ void *handler_context, void *region_context)
+{
+ struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
+ struct mshw0011_handler_data *data = handler_context;
+ struct acpi_connection_info *info = &data->info;
+ struct acpi_resource_i2c_serialbus *sb;
+ struct i2c_client *client = data->client;
+ struct mshw0011_data *cdata = i2c_get_clientdata(client);
+ struct acpi_resource *ares;
+ u32 accessor_type = function >> 16;
+ acpi_status ret;
+ int status = 1;
+
+ ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
+ if (ACPI_FAILURE(ret))
+ return ret;
+
+ if (!value64 || !i2c_acpi_get_i2c_resource(ares, &sb)) {
+ ret = AE_BAD_PARAMETER;
+ goto err;
+ }
+
+ if (accessor_type != ACPI_GSB_ACCESS_ATTRIB_RAW_PROCESS) {
+ ret = AE_BAD_PARAMETER;
+ goto err;
+ }
+
+ if (gsb->cmd.arg0 == MSHW0011_CMD_DEST_ADP1 &&
+ gsb->cmd.arg1 == MSHW0011_CMD_ADP1_PSR) {
+ status = mshw0011_adp_psr(cdata);
+ if (status >= 0) {
+ ret = AE_OK;
+ goto out;
+ } else {
+ ret = AE_ERROR;
+ goto err;
+ }
+ }
+
+ if (gsb->cmd.arg0 != MSHW0011_CMD_DEST_BAT0) {
+ ret = AE_BAD_PARAMETER;
+ goto err;
+ }
+
+ switch (gsb->cmd.arg1) {
+ case MSHW0011_CMD_BAT0_STA:
+ break;
+ case MSHW0011_CMD_BAT0_BIX:
+ ret = mshw0011_bix(cdata, &gsb->bix);
+ break;
+ case MSHW0011_CMD_BAT0_BTP:
+ cdata->trip_point = gsb->cmd.arg2;
+ break;
+ case MSHW0011_CMD_BAT0_BST:
+ ret = mshw0011_bst(cdata, &gsb->bst);
+ break;
+ default:
+ dev_info(&cdata->bat0->dev, "command(0x%02x) is not supported.\n", gsb->cmd.arg1);
+ ret = AE_BAD_PARAMETER;
+ goto err;
+ }
+
+ out:
+ gsb->ret = status;
+ gsb->status = 0;
+
+ err:
+ ACPI_FREE(ares);
+ return ret;
+}
+
+static int mshw0011_install_space_handler(struct i2c_client *client)
+{
+ struct acpi_device *adev;
+ struct mshw0011_handler_data *data;
+ acpi_status status;
+
+ adev = ACPI_COMPANION(&client->dev);
+ if (!adev)
+ return -ENODEV;
+
+ data = kzalloc(sizeof(struct mshw0011_handler_data),
+ GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->client = client;
+ status = acpi_bus_attach_private_data(adev->handle, (void *)data);
+ if (ACPI_FAILURE(status)) {
+ kfree(data);
+ return -ENOMEM;
+ }
+
+ status = acpi_install_address_space_handler(adev->handle,
+ ACPI_ADR_SPACE_GSBUS,
+ &mshw0011_space_handler,
+ NULL,
+ data);
+ if (ACPI_FAILURE(status)) {
+ dev_err(&client->dev, "Error installing i2c space handler\n");
+ acpi_bus_detach_private_data(adev->handle);
+ kfree(data);
+ return -ENOMEM;
+ }
+
+ acpi_dev_clear_dependencies(adev);
+ return 0;
+}
+
+static void mshw0011_remove_space_handler(struct i2c_client *client)
+{
+ struct mshw0011_handler_data *data;
+ acpi_handle handle;
+ acpi_status status;
+
+ handle = ACPI_HANDLE(&client->dev);
+ if (!handle)
+ return;
+
+ acpi_remove_address_space_handler(handle,
+ ACPI_ADR_SPACE_GSBUS,
+ &mshw0011_space_handler);
+
+ status = acpi_bus_get_private_data(handle, (void **)&data);
+ if (ACPI_SUCCESS(status))
+ kfree(data);
+
+ acpi_bus_detach_private_data(handle);
+}
+
+static int mshw0011_probe(struct i2c_client *client)
+{
+ struct i2c_board_info board_info;
+ struct device *dev = &client->dev;
+ struct i2c_client *bat0;
+ struct mshw0011_data *data;
+ int error, mask;
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->adp1 = client;
+ i2c_set_clientdata(client, data);
+
+ memset(&board_info, 0, sizeof(board_info));
+ strscpy(board_info.type, "MSHW0011-bat0", I2C_NAME_SIZE);
+
+ bat0 = i2c_acpi_new_device(dev, 1, &board_info);
+ if (IS_ERR(bat0))
+ return PTR_ERR(bat0);
+
+ data->bat0 = bat0;
+ i2c_set_clientdata(bat0, data);
+
+ error = mshw0011_notify(data, 1, MSHW0011_NOTIFY_GET_VERSION, &mask);
+ if (error)
+ goto out_err;
+
+ data->notify_mask = mask == MSHW0011_EV_2_5_MASK;
+
+ data->poll_task = kthread_run(mshw0011_poll_task, data, "mshw0011_adp");
+ if (IS_ERR(data->poll_task)) {
+ error = PTR_ERR(data->poll_task);
+ dev_err(&client->dev, "Unable to run kthread err %d\n", error);
+ goto out_err;
+ }
+
+ error = mshw0011_install_space_handler(client);
+ if (error)
+ goto out_err;
+
+ return 0;
+
+out_err:
+ if (data->kthread_running)
+ kthread_stop(data->poll_task);
+ i2c_unregister_device(data->bat0);
+ return error;
+}
+
+static void mshw0011_remove(struct i2c_client *client)
+{
+ struct mshw0011_data *cdata = i2c_get_clientdata(client);
+
+ mshw0011_remove_space_handler(client);
+
+ if (cdata->kthread_running)
+ kthread_stop(cdata->poll_task);
+
+ i2c_unregister_device(cdata->bat0);
+}
+
+static const struct acpi_device_id mshw0011_acpi_match[] = {
+ { "MSHW0011", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, mshw0011_acpi_match);
+
+static struct i2c_driver mshw0011_driver = {
+ .probe_new = mshw0011_probe,
+ .remove = mshw0011_remove,
+ .driver = {
+ .name = "mshw0011",
+ .acpi_match_table = mshw0011_acpi_match,
+ },
+};
+module_i2c_driver(mshw0011_driver);
+
+MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
+MODULE_DESCRIPTION("mshw0011 driver");
+MODULE_LICENSE("GPL v2");