diff options
Diffstat (limited to 'drivers/platform/surface/surface3_power.c')
| -rw-r--r-- | drivers/platform/surface/surface3_power.c | 587 |
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"); |