On Tue, 12 Mar 2024, Nikita Travkin wrote:
> Acer Aspire 1 is a Snapdragon 7c based laptop. It uses an embedded
> controller to perform a set of various functions, such as:
>
> - Battery and charger monitoring;
> - Keyboard layout control (i.e. fn_lock settings);
> - USB Type-C DP alt mode HPD notifications;
> - Laptop lid status.
>
> Unfortunately, while all this functionality is implemented in ACPI, it's
> currently not possible to use ACPI to boot Linux on such Qualcomm
> devices. To allow Linux to still support the features provided by EC,
> this driver reimplments the relevant ACPI parts. This allows us to boot
> the laptop with Device Tree and retain all the features.
>
> Signed-off-by: Nikita Travkin <nikita@xxxxxxx>
> ---
> drivers/platform/arm64/Kconfig | 16 +
> drivers/platform/arm64/Makefile | 2 +
> drivers/platform/arm64/acer-aspire1-ec.c | 555 +++++++++++++++++++++++++++++++
> 3 files changed, 573 insertions(+)
>
> diff --git a/drivers/platform/arm64/Kconfig b/drivers/platform/arm64/Kconfig
> index 644b83ede093..07d47879a9e3 100644
> --- a/drivers/platform/arm64/Kconfig
> +++ b/drivers/platform/arm64/Kconfig
> @@ -16,4 +16,20 @@ menuconfig ARM64_PLATFORM_DEVICES
>
> if ARM64_PLATFORM_DEVICES
>
> +config EC_ACER_ASPIRE1
> + tristate "Acer Aspire 1 Emedded Controller driver"
> + depends on I2C
> + depends on DRM
> + depends on POWER_SUPPLY
> + depends on INPUT
> + help
> + Say Y here to enable the EC driver for the (Snapdragon-based)
> + Acer Aspire 1 laptop. The EC handles battery and charging
> + monitoring as well as some misc functions like the lid sensor
> + and USB Type-C DP HPD events.
> +
> + This driver provides battery and AC status support for the mentioned
> + laptop where this information is not properly exposed via the
> + standard ACPI devices.
> +
> endif # ARM64_PLATFORM_DEVICES
> diff --git a/drivers/platform/arm64/Makefile b/drivers/platform/arm64/Makefile
> index f91cdc7155e2..4fcc9855579b 100644
> --- a/drivers/platform/arm64/Makefile
> +++ b/drivers/platform/arm64/Makefile
> @@ -4,3 +4,5 @@
> #
> # This dir should only include drivers for EC-like devices.
> #
> +
> +obj-$(CONFIG_EC_ACER_ASPIRE1) += acer-aspire1-ec.o
> diff --git a/drivers/platform/arm64/acer-aspire1-ec.c b/drivers/platform/arm64/acer-aspire1-ec.c
> new file mode 100644
> index 000000000000..3941e24c5c7c
> --- /dev/null
> +++ b/drivers/platform/arm64/acer-aspire1-ec.c
> @@ -0,0 +1,555 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/* Copyright (c) 2023, Nikita Travkin <nikita@xxxxxxx> */
> +
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/power_supply.h>
> +#include <linux/i2c.h>
> +#include <linux/input.h>
> +#include <linux/delay.h>
> +
> +#include <linux/usb/typec_mux.h>
> +#include <drm/drm_bridge.h>
> +
> +#define ASPIRE_EC_EVENT 0x05
> +
> +#define ASPIRE_EC_EVENT_WATCHDOG 0x20
> +#define ASPIRE_EC_EVENT_KBD_BKL_ON 0x57
> +#define ASPIRE_EC_EVENT_KBD_BKL_OFF 0x58
> +#define ASPIRE_EC_EVENT_LID_CLOSE 0x9b
> +#define ASPIRE_EC_EVENT_LID_OPEN 0x9c
> +#define ASPIRE_EC_EVENT_BKL_UNBLANKED 0x9d
> +#define ASPIRE_EC_EVENT_BKL_BLANKED 0x9e
> +#define ASPIRE_EC_EVENT_FG_INF_CHG 0x85
> +#define ASPIRE_EC_EVENT_FG_STA_CHG 0xc6
> +#define ASPIRE_EC_EVENT_HPD_DIS 0xa3
> +#define ASPIRE_EC_EVENT_HPD_CON 0xa4
> +
> +#define ASPIRE_EC_FG_DYNAMIC 0x07
> +#define ASPIRE_EC_FG_STATIC 0x08
> +
> +#define ASPIRE_EC_FG_FLAG_PRESENT BIT(0)
Add #include <linux/bits.h>
> +#define ASPIRE_EC_FG_FLAG_FULL BIT(1)
> +#define ASPIRE_EC_FG_FLAG_DISCHARGING BIT(2)
> +#define ASPIRE_EC_FG_FLAG_CHARGING BIT(3)
> +
> +#define ASPIRE_EC_RAM_READ 0x20
> +#define ASPIRE_EC_RAM_WRITE 0x21
> +
> +#define ASPIRE_EC_RAM_WATCHDOG 0x19
> +#define ASPIRE_EC_RAM_KBD_MODE 0x43
> +
> +#define ASPIRE_EC_RAM_KBD_FN_EN BIT(0)
> +#define ASPIRE_EC_RAM_KBD_MEDIA_ON_TOP BIT(5)
> +#define ASPIRE_EC_RAM_KBD_ALWAYS_SET BIT(6)
> +#define ASPIRE_EC_RAM_KBD_NUM_LAYER_EN BIT(7)
> +
> +#define ASPIRE_EC_RAM_KBD_MODE_2 0x60
> +
> +#define ASPIRE_EC_RAM_KBD_MEDIA_NOTIFY BIT(3)
> +
> +#define ASPIRE_EC_RAM_HPD_STATUS 0xf4
> +#define ASPIRE_EC_HPD_CONNECTED 0x03
> +
> +#define ASPIRE_EC_RAM_LID_STATUS 0x4c
> +#define ASPIRE_EC_LID_OPEN BIT(6)
> +
> +#define ASPIRE_EC_RAM_ADP 0x40
> +#define ASPIRE_EC_AC_STATUS BIT(0)
> +
> +struct aspire_ec {
> + struct i2c_client *client;
> + struct power_supply *bat_psy;
> + struct power_supply *adp_psy;
> + struct input_dev *idev;
> +
> + bool bridge_configured;
> + struct drm_bridge bridge;
> + struct work_struct work;
Include missing.
> +static int aspire_ec_ram_read(struct i2c_client *client, u8 off, u8 *data, u8 data_len)
> +{
> + i2c_smbus_write_byte_data(client, ASPIRE_EC_RAM_READ, off);
> + i2c_smbus_read_i2c_block_data(client, ASPIRE_EC_RAM_READ, data_len, data);
> + return 0;
> +}
> +
> +static int aspire_ec_ram_write(struct i2c_client *client, u8 off, u8 data)
> +{
> + u8 tmp[2] = {off, data};
> +
> + i2c_smbus_write_i2c_block_data(client, ASPIRE_EC_RAM_WRITE, sizeof(tmp), tmp);
> + return 0;
> +}
> +
> +static irqreturn_t aspire_ec_irq_handler(int irq, void *data)
> +{
> + struct aspire_ec *ec = data;
> + int id;
> + u8 tmp;
> +
> + /*
> + * The original ACPI firmware actually has a small sleep in the handler.
> + *
> + * It seems like in most cases it's not needed but when the device
> + * just exits suspend, our i2c driver has a brief time where data
> + * transfer is not possible yet. So this delay allows us to suppress
> + * quite a bunch of spurious error messages in dmesg. Thus it's kept.
> + */
> + usleep_range(15000, 30000);
> +
> + id = i2c_smbus_read_byte_data(ec->client, ASPIRE_EC_EVENT);
> + if (id < 0) {
> + dev_err(&ec->client->dev, "Failed to read event id: %pe\n", ERR_PTR(id));
> + return IRQ_HANDLED;
> + }
> +
> + switch (id) {
> + case 0x0: /* No event */
> + break;
> +
> + case ASPIRE_EC_EVENT_WATCHDOG:
> + /*
> + * Here acpi responds to the event and clears some bit.
> + * Notify (\_SB.I2C3.BAT1, 0x81) // Information Change
> + * Notify (\_SB.I2C3.ADP1, 0x80) // Status Change
> + */
> + aspire_ec_ram_read(ec->client, ASPIRE_EC_RAM_WATCHDOG, &tmp, sizeof(tmp));
> + aspire_ec_ram_write(ec->client, ASPIRE_EC_RAM_WATCHDOG, tmp & 0xbf);
Magic 0xbf? Is this a clear bit operation which should use
tmp & ~DEFINEDNAME
?
> + break;
> +
> + case ASPIRE_EC_EVENT_LID_CLOSE:
> + /* Notify (\_SB.LID0, 0x80) // Status Change */
> + input_report_switch(ec->idev, SW_LID, 1);
> + input_sync(ec->idev);
> + break;
> +
> + case ASPIRE_EC_EVENT_LID_OPEN:
> + /* Notify (\_SB.LID0, 0x80) // Status Change */
> + input_report_switch(ec->idev, SW_LID, 0);
> + input_sync(ec->idev);
> + break;
> +
> + case ASPIRE_EC_EVENT_FG_INF_CHG:
> + /* Notify (\_SB.I2C3.BAT1, 0x81) // Information Change */
fallthrough;
I'm not 100% sure if it's needed because you only have a comment there but
it surely doesn't hurt to have it.
> + case ASPIRE_EC_EVENT_FG_STA_CHG:
> + /* Notify (\_SB.I2C3.BAT1, 0x80) // Status Change */
> + power_supply_changed(ec->bat_psy);
> + power_supply_changed(ec->adp_psy);
> + break;
> +
> + case ASPIRE_EC_EVENT_HPD_DIS:
> + if (ec->bridge_configured)
> + drm_bridge_hpd_notify(&ec->bridge, connector_status_disconnected);
> + break;
> +
> + case ASPIRE_EC_EVENT_HPD_CON:
> + if (ec->bridge_configured)
> + drm_bridge_hpd_notify(&ec->bridge, connector_status_connected);
> + break;
> +
> + case ASPIRE_EC_EVENT_BKL_BLANKED:
> + case ASPIRE_EC_EVENT_BKL_UNBLANKED:
> + /* Display backlight blanked on FN+F6. No action needed. */
> + break;
> +
> + case ASPIRE_EC_EVENT_KBD_BKL_ON:
> + case ASPIRE_EC_EVENT_KBD_BKL_OFF:
> + /*
> + * There is a keyboard backlight connector on Aspire 1 that is
> + * controlled by FN+F8. There is no kb backlight on the device though.
> + * Seems like this is used on other devices like Acer Spin 7.
> + * No action needed.
> + */
> + break;
> +
> + default:
> + dev_warn(&ec->client->dev, "Unknown event id=0x%x\n", id);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +/*
> + * Power supply.
> + */
> +
> +struct aspire_ec_bat_psy_static_data {
> + u8 unk1;
> + u8 flags;
> + __le16 unk2;
> + __le16 voltage_design;
> + __le16 capacity_full;
> + __le16 unk3;
> + __le16 serial;
> + u8 model_id;
> + u8 vendor_id;
> +} __packed;
> +
> +static const char * const aspire_ec_bat_psy_battery_model[] = {
> + "AP18C4K",
> + "AP18C8K",
> + "AP19B8K",
> + "AP16M4J",
> + "AP16M5J",
> +};
> +
> +static const char * const aspire_ec_bat_psy_battery_vendor[] = {
> + "SANYO",
> + "SONY",
> + "PANASONIC",
> + "SAMSUNG",
> + "SIMPLO",
> + "MOTOROLA",
> + "CELXPERT",
> + "LGC",
> + "GETAC",
> + "MURATA",
> +};
> +
> +struct aspire_ec_bat_psy_dynamic_data {
> + u8 unk1;
> + u8 flags;
> + u8 unk2;
> + __le16 capacity_now;
> + __le16 voltage_now;
> + __le16 current_now;
> + __le16 unk3;
> + __le16 unk4;
> +} __packed;
What are the ARM64 rules when it comes to unaligned access? If it's not
always supported, you need to use get_unaligned_le16() for accessing those
__le16 fields.
> +static int aspire_ec_bat_psy_get_property(struct power_supply *psy,
> + enum power_supply_property psp,
> + union power_supply_propval *val)
> +{
> + struct aspire_ec *ec = power_supply_get_drvdata(psy);
> + struct aspire_ec_bat_psy_static_data sdat;
> + struct aspire_ec_bat_psy_dynamic_data ddat;
> +
> + i2c_smbus_read_i2c_block_data(ec->client, ASPIRE_EC_FG_STATIC, sizeof(sdat), (u8 *)&sdat);
> + i2c_smbus_read_i2c_block_data(ec->client, ASPIRE_EC_FG_DYNAMIC, sizeof(ddat), (u8 *)&ddat);
> +
> + switch (psp) {
> + case POWER_SUPPLY_PROP_STATUS:
> + val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
> + if (ddat.flags & ASPIRE_EC_FG_FLAG_CHARGING)
> + val->intval = POWER_SUPPLY_STATUS_CHARGING;
> + else if (ddat.flags & ASPIRE_EC_FG_FLAG_DISCHARGING)
> + val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
> + else if (ddat.flags & ASPIRE_EC_FG_FLAG_FULL)
> + val->intval = POWER_SUPPLY_STATUS_FULL;
> + break;
> +
> + case POWER_SUPPLY_PROP_VOLTAGE_NOW:
> + val->intval = le16_to_cpu(ddat.voltage_now) * 1000;
linux/units.h provides something that can often be used instead of 10^n
literals.
> + break;
> +
> + case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
> + val->intval = le16_to_cpu(sdat.voltage_design) * 1000;
> + break;
> +
> + case POWER_SUPPLY_PROP_CHARGE_NOW:
> + val->intval = le16_to_cpu(ddat.capacity_now) * 1000;
> + break;
> +
> + case POWER_SUPPLY_PROP_CHARGE_FULL:
> + val->intval = le16_to_cpu(sdat.capacity_full) * 1000;
> + break;
> +
> + case POWER_SUPPLY_PROP_CAPACITY:
> + val->intval = le16_to_cpu(ddat.capacity_now) * 100;
> + val->intval /= le16_to_cpu(sdat.capacity_full);
> + break;
> +
> + case POWER_SUPPLY_PROP_CURRENT_NOW:
> + val->intval = (s16)le16_to_cpu(ddat.current_now) * 1000;
> + break;
> +
> + case POWER_SUPPLY_PROP_PRESENT:
> + val->intval = !!(ddat.flags & ASPIRE_EC_FG_FLAG_PRESENT);
> + break;
> +
> + case POWER_SUPPLY_PROP_SCOPE:
> + val->intval = POWER_SUPPLY_SCOPE_SYSTEM;
> + break;
> +
> + case POWER_SUPPLY_PROP_MODEL_NAME:
> + if (sdat.model_id - 1 < ARRAY_SIZE(aspire_ec_bat_psy_battery_model))
> + val->strval = aspire_ec_bat_psy_battery_model[sdat.model_id - 1];
Underflow handling (also here, the other place was mentioned already)?
> + else
> + val->strval = "Unknown";
> + break;
> +
> + case POWER_SUPPLY_PROP_MANUFACTURER:
> + if (sdat.vendor_id - 3 < ARRAY_SIZE(aspire_ec_bat_psy_battery_vendor))
> + val->strval = aspire_ec_bat_psy_battery_vendor[sdat.vendor_id - 3];
> + else
> + val->strval = "Unknown";
> + break;
> +
> + default:
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static enum power_supply_property aspire_ec_bat_psy_props[] = {
> + POWER_SUPPLY_PROP_STATUS,
> + POWER_SUPPLY_PROP_VOLTAGE_NOW,
> + POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
> + POWER_SUPPLY_PROP_CHARGE_NOW,
> + POWER_SUPPLY_PROP_CHARGE_FULL,
> + POWER_SUPPLY_PROP_CAPACITY,
> + POWER_SUPPLY_PROP_CURRENT_NOW,
> + POWER_SUPPLY_PROP_PRESENT,
> + POWER_SUPPLY_PROP_SCOPE,
> + POWER_SUPPLY_PROP_MODEL_NAME,
> + POWER_SUPPLY_PROP_MANUFACTURER,
> +};
> +
> +static const struct power_supply_desc aspire_ec_bat_psy_desc = {
> + .name = "aspire-ec-bat",
> + .type = POWER_SUPPLY_TYPE_BATTERY,
> + .get_property = aspire_ec_bat_psy_get_property,
> + .properties = aspire_ec_bat_psy_props,
> + .num_properties = ARRAY_SIZE(aspire_ec_bat_psy_props),
> +};
> +
> +static int aspire_ec_adp_psy_get_property(struct power_supply *psy,
> + enum power_supply_property psp,
> + union power_supply_propval *val)
> +{
> + struct aspire_ec *ec = power_supply_get_drvdata(psy);
> + u8 tmp;
> +
> + switch (psp) {
> + case POWER_SUPPLY_PROP_ONLINE:
> + aspire_ec_ram_read(ec->client, ASPIRE_EC_RAM_ADP, &tmp, sizeof(tmp));
> + val->intval = !!(tmp & ASPIRE_EC_AC_STATUS);
> + break;
> +
> + default:
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static enum power_supply_property aspire_ec_adp_psy_props[] = {
> + POWER_SUPPLY_PROP_ONLINE,
> +};
> +
> +static const struct power_supply_desc aspire_ec_adp_psy_desc = {
> + .name = "aspire-ec-adp",
> + .type = POWER_SUPPLY_TYPE_MAINS,
> + .get_property = aspire_ec_adp_psy_get_property,
> + .properties = aspire_ec_adp_psy_props,
> + .num_properties = ARRAY_SIZE(aspire_ec_adp_psy_props),
> +};
> +
> +/*
> + * USB-C DP Alt mode HPD.
> + */
> +
> +static int aspire_ec_bridge_attach(struct drm_bridge *bridge, enum drm_bridge_attach_flags flags)
> +{
> + return flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR ? 0 : -EINVAL;
> +}
> +
> +static void aspire_ec_bridge_update_hpd_work(struct work_struct *work)
> +{
> + struct aspire_ec *ec = container_of(work, struct aspire_ec, work);
> + u8 tmp;
> +
> + aspire_ec_ram_read(ec->client, ASPIRE_EC_RAM_HPD_STATUS, &tmp, sizeof(tmp));
> + if (tmp == ASPIRE_EC_HPD_CONNECTED)
> + drm_bridge_hpd_notify(&ec->bridge, connector_status_connected);
> + else
> + drm_bridge_hpd_notify(&ec->bridge, connector_status_disconnected);
> +}
> +
> +static void aspire_ec_bridge_hpd_enable(struct drm_bridge *bridge)
> +{
> + struct aspire_ec *ec = container_of(bridge, struct aspire_ec, bridge);
> +
> + schedule_work(&ec->work);
> +}
> +
> +static const struct drm_bridge_funcs aspire_ec_bridge_funcs = {
> + .hpd_enable = aspire_ec_bridge_hpd_enable,
> + .attach = aspire_ec_bridge_attach,
> +};
> +
> +/*
> + * Sysfs attributes.
> + */
> +
> +static ssize_t fn_lock_show(struct device *dev, struct device_attribute *attr, char *buf)
> +{
> + struct aspire_ec *ec = i2c_get_clientdata(to_i2c_client(dev));
> + u8 tmp;
> +
> + aspire_ec_ram_read(ec->client, ASPIRE_EC_RAM_KBD_MODE, &tmp, sizeof(tmp));
> +
> + return sysfs_emit(buf, "%d\n", !(tmp & ASPIRE_EC_RAM_KBD_MEDIA_ON_TOP));
%u
> +}
> +
> +static ssize_t fn_lock_store(struct device *dev, struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + struct aspire_ec *ec = i2c_get_clientdata(to_i2c_client(dev));
> + u8 tmp;
> +
> + bool state;
> + int ret;
> +
> + ret = kstrtobool(buf, &state);
> + if (ret)
> + return ret;
> +
> + aspire_ec_ram_read(ec->client, ASPIRE_EC_RAM_KBD_MODE, &tmp, sizeof(tmp));
> +
> + if (state)
> + tmp &= ~ASPIRE_EC_RAM_KBD_MEDIA_ON_TOP;
> + else
> + tmp |= ASPIRE_EC_RAM_KBD_MEDIA_ON_TOP;
> +
> + aspire_ec_ram_write(ec->client, ASPIRE_EC_RAM_KBD_MODE, tmp);
> +
> + return count;
> +}
> +
> +static DEVICE_ATTR_RW(fn_lock);
> +
> +static struct attribute *aspire_ec_attributes[] = {
> + &dev_attr_fn_lock.attr,
> + NULL
> +};
> +
> +static const struct attribute_group aspire_ec_attribute_group = {
> + .attrs = aspire_ec_attributes
> +};
> +
> +static int aspire_ec_probe(struct i2c_client *client)
> +{
> + struct power_supply_config psy_cfg = {0};
> + struct device *dev = &client->dev;
> + struct fwnode_handle *fwnode;
> + struct aspire_ec *ec;
> + int ret;
> + u8 tmp;
> +
> + ec = devm_kzalloc(dev, sizeof(*ec), GFP_KERNEL);
> + if (!ec)
> + return -ENOMEM;
> +
> + ec->client = client;
> + i2c_set_clientdata(client, ec);
> +
> + /* Battery status reports */
> + psy_cfg.drv_data = ec;
> + ec->bat_psy = devm_power_supply_register(dev, &aspire_ec_bat_psy_desc, &psy_cfg);
> + if (IS_ERR(ec->bat_psy))
> + return dev_err_probe(dev, PTR_ERR(ec->bat_psy),
> + "Failed to register battery power supply\n");
> +
> + ec->adp_psy = devm_power_supply_register(dev, &aspire_ec_adp_psy_desc, &psy_cfg);
> + if (IS_ERR(ec->adp_psy))
> + return dev_err_probe(dev, PTR_ERR(ec->adp_psy),
> + "Failed to register ac power supply\n");
AC
> + /* Lid switch */
> + ec->idev = devm_input_allocate_device(dev);
> + if (!ec->idev)
> + return -ENOMEM;
> +
> + ec->idev->name = "aspire-ec";
> + ec->idev->phys = "aspire-ec/input0";
> + input_set_capability(ec->idev, EV_SW, SW_LID);
> +
> + ret = input_register_device(ec->idev);
> + if (ret)
> + return dev_err_probe(dev, ret, "Input device register failed\n");
> +
> + /* Enable the keyboard fn keys */
> + tmp = ASPIRE_EC_RAM_KBD_FN_EN | ASPIRE_EC_RAM_KBD_ALWAYS_SET;
> + tmp |= ASPIRE_EC_RAM_KBD_MEDIA_ON_TOP;
> + aspire_ec_ram_write(client, ASPIRE_EC_RAM_KBD_MODE, tmp);
> +
> + aspire_ec_ram_read(client, ASPIRE_EC_RAM_KBD_MODE_2, &tmp, sizeof(tmp));
> + tmp |= ASPIRE_EC_RAM_KBD_MEDIA_NOTIFY;
> + aspire_ec_ram_write(client, ASPIRE_EC_RAM_KBD_MODE_2, tmp);
> +
> + ret = devm_device_add_group(dev, &aspire_ec_attribute_group);
> + if (ret)
> + return dev_err_probe(dev, ret, "Failed to create attribute group\n");
Can't you just .dev_groups ?
In general, this felt to be in a quite good shape already, good work!
--
i.
