> From: Anson Huang
> Sent: Tuesday, April 16, 2019 11:22 AM
>
> i.MX8QXP is an ARMv8 SoC which has a Cortex-M4 system controller inside,
> the system controller is in charge of controlling power, clock and thermal
> sensors etc..
>
> This patch adds i.MX system controller thermal driver support, Linux kernel has
> to communicate with system controller via MU (message unit) IPC to get each
> thermal sensor's temperature, it supports multiple sensors which are passed
> from device tree, please see the binding doc for details.
>
> Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
> ---
> Changes since V11:
> - move the API of getting thermal zone sensor ID to of-thermal.c as
> generic API;
> - remove unnecessary __packed.
> ---
> drivers/thermal/Kconfig | 11 ++++
> drivers/thermal/Makefile | 1 +
> drivers/thermal/imx_sc_thermal.c | 137
> +++++++++++++++++++++++++++++++++++++++
> 3 files changed, 149 insertions(+)
> create mode 100644 drivers/thermal/imx_sc_thermal.c
>
> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index
> 653aa27..4e4fa7e 100644
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -223,6 +223,17 @@ config IMX_THERMAL
> cpufreq is used as the cooling device to throttle CPUs when the
> passive trip is crossed.
>
> +config IMX_SC_THERMAL
> + tristate "Temperature sensor driver for NXP i.MX SoCs with System
> Controller"
> + depends on (ARCH_MXC && IMX_SCU) || COMPILE_TEST
COMPILE_TEST seems won't work and may cause build issue due to
the dependency of IMX_SCU.
> + depends on OF
> + help
> + Support for Temperature Monitor (TEMPMON) found on NXP i.MX SoCs
> with
> + system controller inside, Linux kernel has to communicate with system
> + controller via MU (message unit) IPC to get temperature from thermal
> + sensor. It supports one critical trip point and one
> + passive trip point for each thermal sensor.
> +
[...]
> +static int imx_sc_thermal_get_temp(void *data, int *temp) {
> + struct imx_sc_msg_misc_get_temp msg;
> + struct imx_sc_rpc_msg *hdr = &msg.hdr;
> + struct imx_sc_sensor *sensor = data;
> + int ret;
> +
> + msg.data.req.resource_id = sensor->resource_id;
> + msg.data.req.type = IMX_SC_C_TEMP;
IMX_SC_C_TEMP duplicates with enum imx_sc_ctrl we already have.
include/linux/firmware/imx/types.h
But I guess you're not want to use a CTRL here.
So please fix the name convention.
> +
> + hdr->ver = IMX_SC_RPC_VERSION;
> + hdr->svc = IMX_SC_RPC_SVC_MISC;
> + hdr->func = IMX_SC_MISC_FUNC_GET_TEMP;
> + hdr->size = 2;
> +
> + ret = imx_scu_call_rpc(thermal_ipc_handle, &msg, true);
> + if (ret) {
> + pr_err("read temp sensor %d failed, ret %d\n",
> + sensor->resource_id, ret);
The error message is meaningless.
Can't convert to dev_err?
> + return ret;
> + }
> +
> + *temp = msg.data.resp.celsius * 1000 + msg.data.resp.tenths * 100;
> +
> + return 0;
> +}
> +
> +static const struct thermal_zone_of_device_ops imx_sc_thermal_ops = {
> + .get_temp = imx_sc_thermal_get_temp,
> +};
> +
> +static int imx_sc_thermal_probe(struct platform_device *pdev) {
> + struct device_node *np, *child;
> + int ret;
> +
> + ret = imx_scu_get_handle(&thermal_ipc_handle);
> + if (ret)
> + return ret;
> +
> + np = of_find_node_by_name(NULL, "thermal-zones");
> + if (!np)
> + return -ENODEV;
> +
> + for_each_available_child_of_node(np, child) {
> + struct of_phandle_args sensor_specs;
> + struct imx_sc_sensor *sensor =
> + devm_kzalloc(&pdev->dev, sizeof(*sensor), GFP_KERNEL);
Usually we do not mix the complicated code in the declare line.
You can move the declarations into the top level to make code more clean.
> + if (!sensor)
> + return -ENOMEM;
> +
> + ret = thermal_zone_of_get_sensor_id(child,
> + &sensor_specs,
It looks a bit strange why need sensor_specs as you even did not use it.
Regards
Dong Aisheng
> + &sensor->resource_id);
> + if (ret < 0) {
> + dev_err(&pdev->dev,
> + "failed to get valid sensor resource id: %d\n",
> + ret);
> + break;
> + }
> +
> + sensor->tzd = devm_thermal_zone_of_sensor_register(&pdev->dev,
> + sensor->resource_id,
> + sensor,
> + &imx_sc_thermal_ops);
> + if (IS_ERR(sensor->tzd)) {
> + dev_err(&pdev->dev, "failed to register thermal zone\n");
> + ret = PTR_ERR(sensor->tzd);
> + break;
> + }
> + }
> +
> + return ret;
> +}
> +
> +static const struct of_device_id imx_sc_thermal_table[] = {
> + { .compatible = "fsl,imx-sc-thermal", },
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, imx_sc_thermal_table);
> +
> +static struct platform_driver imx_sc_thermal_driver = {
> + .probe = imx_sc_thermal_probe,
> + .driver = {
> + .name = "imx-sc-thermal",
> + .of_match_table = imx_sc_thermal_table,
> + },
> +};
> +module_platform_driver(imx_sc_thermal_driver);
> +
> +MODULE_AUTHOR("Anson Huang <Anson.Huang@xxxxxxx>");
> +MODULE_DESCRIPTION("Thermal driver for NXP i.MX SoCs with system
> +controller"); MODULE_LICENSE("GPL v2");
> --
> 2.7.4
