Re: [PATCH v7 2/5] platform: arm64: Add driver for EC found on Qualcomm reference devices
From: Anvesh Jain P <anvesh.p@oss.qualcomm.com>
Date: 2026-03-30 06:44:09
Also in:
linux-arm-msm, lkml, platform-driver-x86
On 3/27/2026 5:20 PM, Ilpo Järvinen wrote:
On Fri, 27 Mar 2026, Anvesh Jain P wrote:quoted
From: Sibi Sankar <sibi.sankar@oss.qualcomm.com> Add Embedded controller driver support for Hamoa/Purwa/Glymur qualcomm reference boards. It handles fan control, temperature sensors, access to EC state changes and supports reporting suspend entry/exit to the EC. Co-developed-by: Maya Matuszczyk <redacted> Signed-off-by: Maya Matuszczyk <redacted> Signed-off-by: Sibi Sankar <sibi.sankar@oss.qualcomm.com> Reviewed-by: Dmitry Baryshkov <redacted> Acked-by: Konrad Dybcio <redacted> Co-developed-by: Anvesh Jain P <anvesh.p@oss.qualcomm.com> Signed-off-by: Anvesh Jain P <anvesh.p@oss.qualcomm.com> --- MAINTAINERS | 8 + drivers/platform/arm64/Kconfig | 12 + drivers/platform/arm64/Makefile | 1 + drivers/platform/arm64/qcom-hamoa-ec.c | 451 +++++++++++++++++++++++++++++++++ 4 files changed, 472 insertions(+)diff --git a/MAINTAINERS b/MAINTAINERS index 30ca84404976..536dfd9adff4 100644 --- a/MAINTAINERS +++ b/MAINTAINERS@@ -21804,6 +21804,14 @@ F: Documentation/devicetree/bindings/misc/qcom,fastrpc.yaml F: drivers/misc/fastrpc.c F: include/uapi/misc/fastrpc.h +QUALCOMM HAMOA EMBEDDED CONTROLLER DRIVER +M: Anvesh Jain P <anvesh.p@oss.qualcomm.com> +M: Sibi Sankar <sibi.sankar@oss.qualcomm.com> +L: linux-arm-msm@vger.kernel.org +S: Maintained +F: Documentation/devicetree/bindings/embedded-controller/qcom,hamoa-ec.yaml +F: drivers/platform/arm64/qcom-hamoa-ec.c + QUALCOMM HEXAGON ARCHITECTURE M: Brian Cain <brian.cain@oss.qualcomm.com> L: linux-hexagon@vger.kernel.orgdiff --git a/drivers/platform/arm64/Kconfig b/drivers/platform/arm64/Kconfig index 10f905d7d6bf..025cdf091f9e 100644 --- a/drivers/platform/arm64/Kconfig +++ b/drivers/platform/arm64/Kconfig@@ -90,4 +90,16 @@ config EC_LENOVO_THINKPAD_T14S Say M or Y here to include this support. +config EC_QCOM_HAMOA + tristate "Embedded Controller driver for Qualcomm Hamoa/Glymur reference devices" + depends on ARCH_QCOM || COMPILE_TEST + depends on I2C + help + Say M or Y here to enable the Embedded Controller driver for Qualcomm + Snapdragon-based Hamoa/Glymur reference devices. The driver handles fan + control, temperature sensors, access to EC state changes and supports + reporting suspend entry/exit to the EC. + + This driver currently supports Hamoa/Purwa/Glymur reference devices. + endif # ARM64_PLATFORM_DEVICESdiff --git a/drivers/platform/arm64/Makefile b/drivers/platform/arm64/Makefile index 60c131cff6a1..7681be4a46e9 100644 --- a/drivers/platform/arm64/Makefile +++ b/drivers/platform/arm64/Makefile@@ -9,3 +9,4 @@ obj-$(CONFIG_EC_ACER_ASPIRE1) += acer-aspire1-ec.o obj-$(CONFIG_EC_HUAWEI_GAOKUN) += huawei-gaokun-ec.o obj-$(CONFIG_EC_LENOVO_YOGA_C630) += lenovo-yoga-c630.o obj-$(CONFIG_EC_LENOVO_THINKPAD_T14S) += lenovo-thinkpad-t14s.o +obj-$(CONFIG_EC_QCOM_HAMOA) += qcom-hamoa-ec.odiff --git a/drivers/platform/arm64/qcom-hamoa-ec.c b/drivers/platform/arm64/qcom-hamoa-ec.c new file mode 100644 index 000000000000..0f883130ac9a --- /dev/null +++ b/drivers/platform/arm64/qcom-hamoa-ec.c@@ -0,0 +1,451 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2024 Maya Matuszczyk <maccraft123mc@gmail.com> + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries. + */ + +#include <linux/bitfield.h> +#include <linux/bits.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/pm.h> +#include <linux/slab.h> +#include <linux/thermal.h> + +#define EC_SCI_EVT_READ_CMD 0x05 +#define EC_FW_VERSION_CMD 0x0e +#define EC_MODERN_STANDBY_CMD 0x23 +#define EC_FAN_DBG_CONTROL_CMD 0x30 +#define EC_SCI_EVT_CONTROL_CMD 0x35 +#define EC_THERMAL_CAP_CMD 0x42 + +#define EC_FW_VERSION_RESP_LEN 4 +#define EC_THERMAL_CAP_RESP_LEN 3 +#define EC_FAN_DEBUG_CMD_LEN 6 +#define EC_FAN_SPEED_DATA_SIZE 4 + +#define EC_MODERN_STANDBY_ENTER 0x01 +#define EC_MODERN_STANDBY_EXIT 0x00 + +#define EC_FAN_DEBUG_MODE_OFF 0 +#define EC_FAN_DEBUG_MODE_ON BIT(0)Add include for BIT().
Added <linux/bits.h> in v6 to address this.
quoted
+#define EC_FAN_ON BIT(1) +#define EC_FAN_DEBUG_TYPE_PWM BIT(2) +#define EC_MAX_FAN_CNT 2 +#define EC_FAN_NAME_SIZE 20 +#define EC_FAN_MAX_PWM 255 + +enum qcom_ec_sci_events { + EC_FAN1_STATUS_CHANGE_EVT = 0x30, + EC_FAN2_STATUS_CHANGE_EVT, + EC_FAN1_SPEED_CHANGE_EVT, + EC_FAN2_SPEED_CHANGE_EVT, + EC_NEW_LUT_SET_EVT, + EC_FAN_PROFILE_SWITCH_EVT, + EC_THERMISTOR_1_THRESHOLD_CROSS_EVT, + EC_THERMISTOR_2_THRESHOLD_CROSS_EVT, + EC_THERMISTOR_3_THRESHOLD_CROSS_EVT, + /* Reserved: 0x39 - 0x3c/0x3f */ + EC_RECOVERED_FROM_RESET_EVT = 0x3d, +}; + +struct qcom_ec_version { + u8 main_version; + u8 sub_version; + u8 test_version; +}; + +struct qcom_ec_thermal_cap { +#define EC_THERMAL_FAN_CNT(x) (FIELD_GET(GENMASK(1, 0), (x))) +#define EC_THERMAL_FAN_TYPE(x) (FIELD_GET(GENMASK(4, 2), (x))) +#define EC_THERMAL_THERMISTOR_MASK(x) (FIELD_GET(GENMASK(7, 0), (x))) + u8 fan_cnt; + u8 fan_type; + u8 thermistor_mask; +}; + +struct qcom_ec_cooling_dev { + struct thermal_cooling_device *cdev; + struct device *parent_dev; + u8 fan_id; + u8 state; +}; + +struct qcom_ec { + struct qcom_ec_cooling_dev *ec_cdev; + struct qcom_ec_thermal_cap thermal_cap; + struct qcom_ec_version version; + struct i2c_client *client; +}; + +static int qcom_ec_read(struct qcom_ec *ec, u8 cmd, u8 resp_len, u8 *resp) +{ + int ret; + + ret = i2c_smbus_read_i2c_block_data(ec->client, cmd, resp_len, resp); + + if (ret < 0) + return ret; + else if (ret == 0 || ret == 0xff) + return -EOPNOTSUPP; + + if (resp[0] >= resp_len) + return -EINVAL; + + return 0; +} + +/* + * EC Device Firmware Version: + * + * Read Response: + * ---------------------------------------------------------------------- + * | Offset | Name | Description | + * ---------------------------------------------------------------------- + * | 0x00 | Byte count | Number of bytes in response | + * | | | (excluding byte count) | + * ---------------------------------------------------------------------- + * | 0x01 | Test-version | Test-version of EC firmware | + * ---------------------------------------------------------------------- + * | 0x02 | Sub-version | Sub-version of EC firmware | + * ---------------------------------------------------------------------- + * | 0x03 | Main-version | Main-version of EC firmware | + * ---------------------------------------------------------------------- + * + */ +static int qcom_ec_read_fw_version(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct qcom_ec *ec = i2c_get_clientdata(client); + struct qcom_ec_version *version = &ec->version; + u8 resp[EC_FW_VERSION_RESP_LEN]; + int ret; + + ret = qcom_ec_read(ec, EC_FW_VERSION_CMD, EC_FW_VERSION_RESP_LEN, resp); + if (ret < 0) + return ret; + + version->main_version = resp[3]; + version->sub_version = resp[2]; + version->test_version = resp[1]; + + dev_dbg(dev, "EC Version %d.%d.%d\n", + version->main_version, version->sub_version, version->test_version); + + return 0; +} + +/* + * EC Device Thermal Capabilities: + * + * Read Response: + * ------------------------------------------------------------------------------ + * | Offset | Name | Description | + * ------------------------------------------------------------------------------ + * | 0x00 | Byte count | Number of bytes in response | + * | | | (excluding byte count) | + * ------------------------------------------------------------------------------ + * | 0x02 (LSB) | EC Thermal | Bit 0-1: Number of fans | + * | 0x3 | Capabilities | Bit 2-4: Type of fan |0x03 ?
Typo, Will fix to 0x03 in next respin.
quoted
+ * | | | Bit 5-6: Reserved | + * | | | Bit 7: Data Valid/Invalid | + * | | | (Valid - 1, Invalid - 0) | + * | | | Bit 8-15: Thermistor 0 - 7 presence | + * | | | (1 present, 0 absent) | + * ------------------------------------------------------------------------------ + * + */ +static int qcom_ec_thermal_capabilities(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct qcom_ec *ec = i2c_get_clientdata(client); + struct qcom_ec_thermal_cap *cap = &ec->thermal_cap; + u8 resp[EC_THERMAL_CAP_RESP_LEN]; + int ret; + + ret = qcom_ec_read(ec, EC_THERMAL_CAP_CMD, EC_THERMAL_CAP_RESP_LEN, resp); + if (ret < 0) + return ret; + + cap->fan_cnt = min(EC_MAX_FAN_CNT, EC_THERMAL_FAN_CNT(resp[1])); + cap->fan_type = EC_THERMAL_FAN_TYPE(resp[1]); + cap->thermistor_mask = EC_THERMAL_THERMISTOR_MASK(resp[2]); + + dev_dbg(dev, "Fan count: %d Fan Type: %d Thermistor Mask: %x\n",Please add include for dev_dbg(). It seems you've missed at least some of my comments to v5, please recheck those comments. I won't look further for now. -- i.
Added <linux/device.h> for dev_dbg() in v6, will include <linux/dev_printk.h> as well in in v8. That said, all your v5 comments have been addressed, here is a summary of what was fixed: - Add <linux/bits.h> for BIT() - Add <linux/err.h> for IS_ERR() - Switch thermistor mask format specifier from %d to %x - Add missing braces - Remove empty line within variable declarations - Change loop counter i to unsigned int - Replace snprintf() with scnprintf() - Use sizeof(name) instead of the EC_FAN_NAME_SIZE macro directly - Condense devm_thermal_of_cooling_device_register() to 2 lines Apologies if it appeared otherwise. If anything was missed, please do point it out and I will address it in the next respin.
quoted
+ cap->fan_cnt, cap->fan_type, cap->thermistor_mask); + + return 0; +} + +static irqreturn_t qcom_ec_irq(int irq, void *data) +{ + struct qcom_ec *ec = data; + struct device *dev = &ec->client->dev; + int val; + + val = i2c_smbus_read_byte_data(ec->client, EC_SCI_EVT_READ_CMD); + if (val < 0) { + dev_err_ratelimited(dev, "Failed to read EC SCI Event: %d\n", val); + return IRQ_HANDLED; + } + + switch (val) { + case EC_FAN1_STATUS_CHANGE_EVT: + dev_dbg_ratelimited(dev, "Fan1 status changed\n"); + break; + case EC_FAN2_STATUS_CHANGE_EVT: + dev_dbg_ratelimited(dev, "Fan2 status changed\n"); + break; + case EC_FAN1_SPEED_CHANGE_EVT: + dev_dbg_ratelimited(dev, "Fan1 speed crossed low/high trip point\n"); + break; + case EC_FAN2_SPEED_CHANGE_EVT: + dev_dbg_ratelimited(dev, "Fan2 speed crossed low/high trip point\n"); + break; + case EC_NEW_LUT_SET_EVT: + dev_dbg_ratelimited(dev, "New LUT set\n"); + break; + case EC_FAN_PROFILE_SWITCH_EVT: + dev_dbg_ratelimited(dev, "FAN Profile switched\n"); + break; + case EC_THERMISTOR_1_THRESHOLD_CROSS_EVT: + dev_dbg_ratelimited(dev, "Thermistor 1 threshold crossed\n"); + break; + case EC_THERMISTOR_2_THRESHOLD_CROSS_EVT: + dev_dbg_ratelimited(dev, "Thermistor 2 threshold crossed\n"); + break; + case EC_THERMISTOR_3_THRESHOLD_CROSS_EVT: + dev_dbg_ratelimited(dev, "Thermistor 3 threshold crossed\n"); + break; + case EC_RECOVERED_FROM_RESET_EVT: + dev_dbg_ratelimited(dev, "EC recovered from reset\n"); + break; + default: + dev_notice_ratelimited(dev, "Unknown EC event: %d\n", val); + break; + } + + return IRQ_HANDLED; +} + +static int qcom_ec_sci_evt_control(struct device *dev, bool enable) +{ + struct i2c_client *client = to_i2c_client(dev); + + return i2c_smbus_write_byte_data(client, EC_SCI_EVT_CONTROL_CMD, !!enable); +} + +static int qcom_ec_fan_get_max_state(struct thermal_cooling_device *cdev, unsigned long *state) +{ + *state = EC_FAN_MAX_PWM; + + return 0; +} + +static int qcom_ec_fan_get_cur_state(struct thermal_cooling_device *cdev, unsigned long *state) +{ + struct qcom_ec_cooling_dev *ec_cdev = cdev->devdata; + + *state = ec_cdev->state; + + return 0; +} + +/* + * Fan Debug control command: + * + * Command Payload: + * -------------------------------------------------------------------------------------- + * | Offset | Name | Description | + * -------------------------------------------------------------------------------------- + * | 0x00 | Command | Fan control command | + * -------------------------------------------------------------------------------------- + * | 0x01 | Fan ID | 0x1 : Fan 1 | + * | | | 0x2 : Fan 2 | + * -------------------------------------------------------------------------------------- + * | 0x02 | Byte count = 4| Size of data to set fan speed | + * -------------------------------------------------------------------------------------- + * | 0x03 | Mode | Bit 0: Debug Mode On/Off (0 - OFF, 1 - ON ) | + * | | | Bit 1: Fan On/Off (0 - Off, 1 - ON) | + * | | | Bit 2: Debug Type (0 - RPM, 1 - PWM) | + * -------------------------------------------------------------------------------------- + * | 0x04 (LSB) | Speed in RPM | RPM value, if mode selected is RPM | + * | 0x05 | | | + * -------------------------------------------------------------------------------------- + * | 0x06 | Speed in PWM | PWM value, if mode selected is PWM (0 - 255) | + * ______________________________________________________________________________________ + * + */ +static int qcom_ec_fan_debug_mode_off(struct qcom_ec_cooling_dev *ec_cdev) +{ + struct device *dev = ec_cdev->parent_dev; + struct i2c_client *client = to_i2c_client(dev); + u8 request[6] = { ec_cdev->fan_id, EC_FAN_SPEED_DATA_SIZE, + EC_FAN_DEBUG_MODE_OFF, 0, 0, 0 }; + int ret; + + ret = i2c_smbus_write_i2c_block_data(client, EC_FAN_DBG_CONTROL_CMD, + sizeof(request), request); + if (ret) { + dev_err(dev, "Failed to turn off fan%d debug mode: %d\n", + ec_cdev->fan_id, ret); + } + + return ret; +} + +static int qcom_ec_fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state) +{ + struct qcom_ec_cooling_dev *ec_cdev = cdev->devdata; + struct device *dev = ec_cdev->parent_dev; + struct i2c_client *client = to_i2c_client(dev); + u8 request[6] = { ec_cdev->fan_id, EC_FAN_SPEED_DATA_SIZE, + EC_FAN_DEBUG_MODE_ON | EC_FAN_ON | EC_FAN_DEBUG_TYPE_PWM, + 0, 0, state }; + int ret; + + ret = i2c_smbus_write_i2c_block_data(client, EC_FAN_DBG_CONTROL_CMD, + sizeof(request), request); + if (ret) { + dev_err(dev, "Failed to set fan pwm: %d\n", ret); + return ret; + } + + ec_cdev->state = state; + + return 0; +} + +static const struct thermal_cooling_device_ops qcom_ec_thermal_ops = { + .get_max_state = qcom_ec_fan_get_max_state, + .get_cur_state = qcom_ec_fan_get_cur_state, + .set_cur_state = qcom_ec_fan_set_cur_state, +}; + +static int qcom_ec_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + + return i2c_smbus_write_byte_data(client, EC_MODERN_STANDBY_CMD, + EC_MODERN_STANDBY_ENTER); +} + +static int qcom_ec_suspend(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + + return i2c_smbus_write_byte_data(client, EC_MODERN_STANDBY_CMD, + EC_MODERN_STANDBY_EXIT); +} + +static int qcom_ec_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct qcom_ec *ec; + unsigned int i; + int ret; + + ec = devm_kzalloc(dev, sizeof(*ec), GFP_KERNEL); + if (!ec) + return -ENOMEM; + + ec->client = client; + + ret = devm_request_threaded_irq(dev, client->irq, NULL, qcom_ec_irq, + IRQF_ONESHOT, "qcom_ec", ec); + if (ret < 0) + return ret; + + i2c_set_clientdata(client, ec); + + ret = qcom_ec_read_fw_version(dev); + if (ret < 0) + return dev_err_probe(dev, ret, "Failed to read EC firmware version\n"); + + ret = qcom_ec_sci_evt_control(dev, true); + if (ret < 0) + return dev_err_probe(dev, ret, "Failed to enable SCI events\n"); + + ret = qcom_ec_thermal_capabilities(dev); + if (ret < 0) + return dev_err_probe(dev, ret, "Failed to read thermal capabilities\n"); + + if (ec->thermal_cap.fan_cnt == 0) { + dev_warn(dev, FW_BUG "Failed to get fan count, firmware update required\n"); + return 0; + } + + ec->ec_cdev = devm_kcalloc(dev, ec->thermal_cap.fan_cnt, sizeof(*ec->ec_cdev), GFP_KERNEL); + if (!ec->ec_cdev) + return -ENOMEM; + + for (i = 0; i < ec->thermal_cap.fan_cnt; i++) { + struct qcom_ec_cooling_dev *ec_cdev = &ec->ec_cdev[i]; + char name[EC_FAN_NAME_SIZE]; + + scnprintf(name, sizeof(name), "qcom_ec_fan_%u", i); + ec_cdev->fan_id = i + 1; + ec_cdev->parent_dev = dev; + + ec_cdev->cdev = devm_thermal_of_cooling_device_register(dev, NULL, name, ec_cdev, + &qcom_ec_thermal_ops); + if (IS_ERR(ec_cdev->cdev)) { + return dev_err_probe(dev, PTR_ERR(ec_cdev->cdev), + "Failed to register fan%d cooling device\n", i); + } + } + + return 0; +} + +static void qcom_ec_remove(struct i2c_client *client) +{ + struct qcom_ec *ec = i2c_get_clientdata(client); + struct device *dev = &client->dev; + int ret; + + ret = qcom_ec_sci_evt_control(dev, false); + if (ret < 0) + dev_err(dev, "Failed to disable SCI events: %d\n", ret); + + for (int i = 0; i < ec->thermal_cap.fan_cnt; i++) { + struct qcom_ec_cooling_dev *ec_cdev = &ec->ec_cdev[i]; + + qcom_ec_fan_debug_mode_off(ec_cdev); + } +} + +static const struct of_device_id qcom_ec_of_match[] = { + { .compatible = "qcom,hamoa-crd-ec" }, + {} +}; +MODULE_DEVICE_TABLE(of, qcom_ec_of_match); + +static const struct i2c_device_id qcom_ec_i2c_id_table[] = { + { "qcom-hamoa-ec", }, + {} +}; +MODULE_DEVICE_TABLE(i2c, qcom_ec_i2c_id_table); + +static DEFINE_SIMPLE_DEV_PM_OPS(qcom_ec_pm_ops, + qcom_ec_suspend, + qcom_ec_resume); + +static struct i2c_driver qcom_ec_i2c_driver = { + .driver = { + .name = "qcom-hamoa-ec", + .of_match_table = qcom_ec_of_match, + .pm = &qcom_ec_pm_ops + }, + .probe = qcom_ec_probe, + .remove = qcom_ec_remove, + .id_table = qcom_ec_i2c_id_table, +}; +module_i2c_driver(qcom_ec_i2c_driver); + +MODULE_DESCRIPTION("QCOM Hamoa Embedded Controller"); +MODULE_LICENSE("GPL");
-- Best Regards, Anvesh