Implement the new platform driver cros_ec_charge_state to have low finer
control over the charge current flow through the charge chip connected
on ChromeOS Embedded Controller (EC).
The driver reads configured charge chip configurations from the device
tree, and register these chip controls as thermal zone devices, so they
are controllable from the thermal subsystem.
As such, corresponding DTS changes are needed, and here is a sample DTS
configuration:
```
&cros_ec {
charge-chip-battery {
compatible = "google,cros-ec-charge-state";
type = "charge";
min-milliamp = <150>;
max-milliamp = <5000>;
};
};
```
Signed-off-by: Sung-Chi, Li <lschyi@chromium.org>
---
drivers/platform/chrome/Kconfig | 11 ++
drivers/platform/chrome/Makefile | 1 +
drivers/platform/chrome/cros_ec_charge_state.c | 215 +++++++++++++++++++++++++
3 files changed, 227 insertions(+)
diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig
index 7dbeb786352a..34d00d8823cb 100644
--- a/drivers/platform/chrome/Kconfig
+++ b/drivers/platform/chrome/Kconfig
@@ -297,6 +297,17 @@ config CROS_TYPEC_SWITCH
To compile this driver as a module, choose M here: the module will be
called cros_typec_switch.
+config CROS_CHARGE_STATE
+ tristate "ChromeOS EC Charger Chip Control"
+ depends on MFD_CROS_EC_DEV
+ default MFD_CROS_EC_DEV
+ help
+ If you say Y here, you get support for configuring the battery
+ charging and system input current.
+
+ To compile this driver as a module, choose M here: the module will be
+ called cros-ec-charge-state.
+
source "drivers/platform/chrome/wilco_ec/Kconfig"
# Kunit test cases
diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile
index 2dcc6ccc2302..01c7154ae119 100644
--- a/drivers/platform/chrome/Makefile
+++ b/drivers/platform/chrome/Makefile
@@ -32,6 +32,7 @@ obj-$(CONFIG_CROS_EC_SYSFS) += cros_ec_sysfs.o
obj-$(CONFIG_CROS_HPS_I2C) += cros_hps_i2c.o
obj-$(CONFIG_CROS_USBPD_LOGGER) += cros_usbpd_logger.o
obj-$(CONFIG_CROS_USBPD_NOTIFY) += cros_usbpd_notify.o
+obj-$(CONFIG_CROS_CHARGE_STATE) += cros_ec_charge_state.o
obj-$(CONFIG_WILCO_EC) += wilco_ec/
diff --git a/drivers/platform/chrome/cros_ec_charge_state.c b/drivers/platform/chrome/cros_ec_charge_state.c
new file mode 100644
index 000000000000..3fed5b48bc92
--- /dev/null
+++ b/drivers/platform/chrome/cros_ec_charge_state.c
@@ -0,0 +1,215 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Charge state driver for ChromeOS Embedded Controller
+ *
+ * Copyright 2024 Google LLC
+ *
+ * This driver exports the low level control over charge chip connected to EC
+ * which allows to manipulate the current used to charge the battery, and also
+ * manipulate the current input to the whole system.
+ * This driver also registers that charge chip as a thermal cooling device.
+ */
+
+#include <linux/of.h>
+#include <linux/platform_data/cros_ec_commands.h>
+#include <linux/platform_data/cros_ec_proto.h>
+#include <linux/platform_device.h>
+#include <linux/thermal.h>
+
+#define DRV_NAME "cros-ec-charge-state"
+#define CHARGE_TYPE_CHARGE "charge"
+#define CHARGE_TYPE_INPUT "input"
+
+struct cros_ec_charge_state_data {
+ struct cros_ec_device *ec_dev;
+ struct device *dev;
+ enum charge_state_params charge_type;
+ uint32_t min_milliamp;
+ uint32_t max_milliamp;
+};
+
+static int
+cros_ec_charge_state_get_current_limit(struct cros_ec_device *ec_dev,
+ enum charge_state_params charge_type,
+ uint32_t *limit)
+{
+ struct ec_params_charge_state param;
+ struct ec_response_charge_state state;
+ int ret;
+
+ param.cmd = CHARGE_STATE_CMD_GET_PARAM;
+ param.get_param.param = charge_type;
+ ret = cros_ec_cmd(ec_dev, 0, EC_CMD_CHARGE_STATE, ¶m, sizeof(param),
+ &state, sizeof(state));
+ if (ret < 0)
+ return ret;
+
+ *limit = cpu_to_le32(state.get_param.value);
+ return 0;
+}
+
+static int
+cros_ec_charge_state_set_current_limit(struct cros_ec_device *ec_dev,
+ enum charge_state_params charge_type,
+ uint32_t limit)
+{
+ struct ec_params_charge_state param;
+ int ret;
+
+ param.cmd = CHARGE_STATE_CMD_SET_PARAM;
+ param.set_param.param = charge_type;
+ param.set_param.value = cpu_to_le32(limit);
+ ret = cros_ec_cmd(ec_dev, 0, EC_CMD_CHARGE_STATE, ¶m, sizeof(param),
+ NULL, 0);
+ return (ret < 0) ? ret : 0;
+}
+
+static int
+cros_ec_charge_state_get_max_state(struct thermal_cooling_device *cdev,
+ unsigned long *state)
+{
+ struct cros_ec_charge_state_data *data = cdev->devdata;
+ *state = data->max_milliamp;
+ return 0;
+}
+
+static int
+cros_ec_charge_state_get_cur_state(struct thermal_cooling_device *cdev,
+ unsigned long *state)
+{
+ struct cros_ec_charge_state_data *data = cdev->devdata;
+ uint32_t limit;
+ int ret;
+
+ ret = cros_ec_charge_state_get_current_limit(data->ec_dev,
+ data->charge_type, &limit);
+ if (ret) {
+ dev_err(data->dev, "failed to get current state: %d", ret);
+ return ret;
+ }
+
+ *state = data->max_milliamp - limit;
+ return 0;
+}
+
+static int
+cros_ec_charge_state_set_cur_state(struct thermal_cooling_device *cdev,
+ unsigned long state)
+{
+ struct cros_ec_charge_state_data *data = cdev->devdata;
+ uint32_t limit = data->max_milliamp - state;
+
+ if (limit < data->min_milliamp) {
+ dev_warn(
+ data->dev,
+ "failed to set current %u lower than minimum %d; set to minimum",
+ limit, data->min_milliamp);
+ limit = data->min_milliamp;
+ }
+
+ state = data->max_milliamp - limit;
+ return cros_ec_charge_state_set_current_limit(
+ data->ec_dev, data->charge_type, (uint32_t)state);
+}
+
+static const struct thermal_cooling_device_ops
+ cros_ec_charge_state_cooling_device_ops = {
+ .get_max_state = cros_ec_charge_state_get_max_state,
+ .get_cur_state = cros_ec_charge_state_get_cur_state,
+ .set_cur_state = cros_ec_charge_state_set_cur_state,
+ };
+
+static int
+cros_ec_charge_state_register_charge_chip(struct device *dev,
+ struct device_node *node,
+ struct cros_ec_device *cros_ec)
+{
+ struct cros_ec_charge_state_data *data;
+ struct thermal_cooling_device *cdev;
+ const char *type_val = NULL;
+ int ret;
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ ret = of_property_read_string(node, "type", &type_val);
+ if (ret) {
+ dev_err(dev, "failed to get charge type: %d", ret);
+ return ret;
+ }
+
+ if (!strcmp(type_val, CHARGE_TYPE_CHARGE)) {
+ data->charge_type = CS_PARAM_CHG_CURRENT;
+ } else if (!strcmp(type_val, CHARGE_TYPE_INPUT)) {
+ data->charge_type = CS_PARAM_CHG_INPUT_CURRENT;
+ } else {
+ dev_err(dev, "unknown charge type: %s", type_val);
+ return -1;
+ }
+
+ ret = of_property_read_u32(node, "min-milliamp", &data->min_milliamp);
+ if (ret) {
+ dev_err(dev, "failed to get min-milliamp data: %d", ret);
+ return ret;
+ }
+
+ ret = of_property_read_u32(node, "max-milliamp", &data->max_milliamp);
+ if (ret) {
+ dev_err(dev, "failed to get max-milliamp data: %d", ret);
+ return ret;
+ }
+
+ data->ec_dev = cros_ec;
+ data->dev = dev;
+
+ cdev = devm_thermal_of_cooling_device_register(
+ dev, node, node->name, data,
+ &cros_ec_charge_state_cooling_device_ops);
+ if (IS_ERR_VALUE(cdev)) {
+ dev_err(dev,
+ "failed to register charge chip %s as cooling device: %pe",
+ node->name, cdev);
+ return PTR_ERR(cdev);
+ }
+
+ return 0;
+}
+
+static int cros_ec_charge_state_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent);
+ struct cros_ec_device *cros_ec = ec_dev->ec_dev;
+ struct device_node *child;
+
+ for_each_available_child_of_node(cros_ec->dev->of_node, child) {
+ if (!of_device_is_compatible(child,
+ "google,cros-ec-charge-state"))
+ continue;
+ if (cros_ec_charge_state_register_charge_chip(dev, child,
+ cros_ec))
+ continue;
+ }
+
+ return 0;
+}
+
+static const struct platform_device_id cros_ec_charge_state_id[] = {
+ { DRV_NAME, 0 },
+ {}
+};
+
+static struct platform_driver cros_ec_chargedev_driver = {
+ .driver = {
+ .name = DRV_NAME,
+ },
+ .probe = cros_ec_charge_state_probe,
+};
+
+module_platform_driver(cros_ec_chargedev_driver);
+
+MODULE_DEVICE_TABLE(platform, cros_ec_charge_state_id);
+MODULE_DESCRIPTION("ChromeOS EC Charge State Driver");
+MODULE_AUTHOR("Sung-Chi, Li <lschyi@chromium.org>");
+MODULE_LICENSE("GPL");
--
2.47.0.338.g60cca15819-googOn 2024-11-18 17:33:46+0800, Sung-Chi, Li wrote:
> Implement the new platform driver cros_ec_charge_state to have low finer
> control over the charge current flow through the charge chip connected
> on ChromeOS Embedded Controller (EC).
>
> The driver reads configured charge chip configurations from the device
> tree, and register these chip controls as thermal zone devices, so they
> are controllable from the thermal subsystem.
>
> As such, corresponding DTS changes are needed, and here is a sample DTS
> configuration:
>
> ```
> &cros_ec {
> charge-chip-battery {
> compatible = "google,cros-ec-charge-state";
> type = "charge";
> min-milliamp = <150>;
> max-milliamp = <5000>;
> };
> };
> ```
>
> Signed-off-by: Sung-Chi, Li <lschyi@chromium.org>
> ---
> drivers/platform/chrome/Kconfig | 11 ++
> drivers/platform/chrome/Makefile | 1 +
> drivers/platform/chrome/cros_ec_charge_state.c | 215 +++++++++++++++++++++++++
> 3 files changed, 227 insertions(+)
>
> diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig
> index 7dbeb786352a..34d00d8823cb 100644
> --- a/drivers/platform/chrome/Kconfig
> +++ b/drivers/platform/chrome/Kconfig
> @@ -297,6 +297,17 @@ config CROS_TYPEC_SWITCH
> To compile this driver as a module, choose M here: the module will be
> called cros_typec_switch.
>
> +config CROS_CHARGE_STATE
> + tristate "ChromeOS EC Charger Chip Control"
> + depends on MFD_CROS_EC_DEV
Should depend on THERMAL_OF.
Otherwise the driver will be built and loaded on non-OF platforms but
probing can never succeed.
> + default MFD_CROS_EC_DEV
> + help
> + If you say Y here, you get support for configuring the battery
> + charging and system input current.
> +
> + To compile this driver as a module, choose M here: the module will be
> + called cros-ec-charge-state.
> +
> source "drivers/platform/chrome/wilco_ec/Kconfig"
>
> # Kunit test cases
> diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile
> index 2dcc6ccc2302..01c7154ae119 100644
> --- a/drivers/platform/chrome/Makefile
> +++ b/drivers/platform/chrome/Makefile
> @@ -32,6 +32,7 @@ obj-$(CONFIG_CROS_EC_SYSFS) += cros_ec_sysfs.o
> obj-$(CONFIG_CROS_HPS_I2C) += cros_hps_i2c.o
> obj-$(CONFIG_CROS_USBPD_LOGGER) += cros_usbpd_logger.o
> obj-$(CONFIG_CROS_USBPD_NOTIFY) += cros_usbpd_notify.o
> +obj-$(CONFIG_CROS_CHARGE_STATE) += cros_ec_charge_state.o
>
> obj-$(CONFIG_WILCO_EC) += wilco_ec/
>
> diff --git a/drivers/platform/chrome/cros_ec_charge_state.c b/drivers/platform/chrome/cros_ec_charge_state.c
> new file mode 100644
> index 000000000000..3fed5b48bc92
> --- /dev/null
> +++ b/drivers/platform/chrome/cros_ec_charge_state.c
> @@ -0,0 +1,215 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Charge state driver for ChromeOS Embedded Controller
> + *
> + * Copyright 2024 Google LLC
> + *
> + * This driver exports the low level control over charge chip connected to EC
> + * which allows to manipulate the current used to charge the battery, and also
> + * manipulate the current input to the whole system.
> + * This driver also registers that charge chip as a thermal cooling device.
> + */
> +
> +#include <linux/of.h>
> +#include <linux/platform_data/cros_ec_commands.h>
> +#include <linux/platform_data/cros_ec_proto.h>
> +#include <linux/platform_device.h>
> +#include <linux/thermal.h>
> +
> +#define DRV_NAME "cros-ec-charge-state"
> +#define CHARGE_TYPE_CHARGE "charge"
> +#define CHARGE_TYPE_INPUT "input"
> +
> +struct cros_ec_charge_state_data {
> + struct cros_ec_device *ec_dev;
> + struct device *dev;
> + enum charge_state_params charge_type;
> + uint32_t min_milliamp;
> + uint32_t max_milliamp;
> +};
> +
> +static int
> +cros_ec_charge_state_get_current_limit(struct cros_ec_device *ec_dev,
> + enum charge_state_params charge_type,
> + uint32_t *limit)
> +{
> + struct ec_params_charge_state param;
> + struct ec_response_charge_state state;
> + int ret;
> +
> + param.cmd = CHARGE_STATE_CMD_GET_PARAM;
> + param.get_param.param = charge_type;
> + ret = cros_ec_cmd(ec_dev, 0, EC_CMD_CHARGE_STATE, ¶m, sizeof(param),
> + &state, sizeof(state));
> + if (ret < 0)
> + return ret;
> +
> + *limit = cpu_to_le32(state.get_param.value);
The cros_ec core itself does not handle BE systems.
So I'm not sure if it's worth trying to handle it in the driver.
> + return 0;
> +}
> +
> +static int
> +cros_ec_charge_state_set_current_limit(struct cros_ec_device *ec_dev,
> + enum charge_state_params charge_type,
> + uint32_t limit)
> +{
> + struct ec_params_charge_state param;
> + int ret;
> +
> + param.cmd = CHARGE_STATE_CMD_SET_PARAM;
> + param.set_param.param = charge_type;
> + param.set_param.value = cpu_to_le32(limit);
> + ret = cros_ec_cmd(ec_dev, 0, EC_CMD_CHARGE_STATE, ¶m, sizeof(param),
> + NULL, 0);
> + return (ret < 0) ? ret : 0;
> +}
> +
> +static int
> +cros_ec_charge_state_get_max_state(struct thermal_cooling_device *cdev,
> + unsigned long *state)
> +{
> + struct cros_ec_charge_state_data *data = cdev->devdata;
> + *state = data->max_milliamp;
> + return 0;
> +}
> +
> +static int
> +cros_ec_charge_state_get_cur_state(struct thermal_cooling_device *cdev,
> + unsigned long *state)
> +{
> + struct cros_ec_charge_state_data *data = cdev->devdata;
> + uint32_t limit;
> + int ret;
> +
> + ret = cros_ec_charge_state_get_current_limit(data->ec_dev,
> + data->charge_type, &limit);
> + if (ret) {
> + dev_err(data->dev, "failed to get current state: %d", ret);
> + return ret;
> + }
> +
> + *state = data->max_milliamp - limit;
> + return 0;
> +}
> +
> +static int
> +cros_ec_charge_state_set_cur_state(struct thermal_cooling_device *cdev,
> + unsigned long state)
> +{
> + struct cros_ec_charge_state_data *data = cdev->devdata;
> + uint32_t limit = data->max_milliamp - state;
> +
> + if (limit < data->min_milliamp) {
> + dev_warn(
> + data->dev,
> + "failed to set current %u lower than minimum %d; set to minimum",
> + limit, data->min_milliamp);
> + limit = data->min_milliamp;
> + }
> +
> + state = data->max_milliamp - limit;
> + return cros_ec_charge_state_set_current_limit(
> + data->ec_dev, data->charge_type, (uint32_t)state);
> +}
> +
> +static const struct thermal_cooling_device_ops
> + cros_ec_charge_state_cooling_device_ops = {
> + .get_max_state = cros_ec_charge_state_get_max_state,
> + .get_cur_state = cros_ec_charge_state_get_cur_state,
> + .set_cur_state = cros_ec_charge_state_set_cur_state,
> + };
> +
> +static int
> +cros_ec_charge_state_register_charge_chip(struct device *dev,
> + struct device_node *node,
> + struct cros_ec_device *cros_ec)
> +{
> + struct cros_ec_charge_state_data *data;
> + struct thermal_cooling_device *cdev;
> + const char *type_val = NULL;
> + int ret;
> +
> + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> + if (!data)
> + return -ENOMEM;
> +
> + ret = of_property_read_string(node, "type", &type_val);
> + if (ret) {
> + dev_err(dev, "failed to get charge type: %d", ret);
> + return ret;
return dev_err_probe(dev, ...)
> + }
> +
> + if (!strcmp(type_val, CHARGE_TYPE_CHARGE)) {
> + data->charge_type = CS_PARAM_CHG_CURRENT;
> + } else if (!strcmp(type_val, CHARGE_TYPE_INPUT)) {
> + data->charge_type = CS_PARAM_CHG_INPUT_CURRENT;
> + } else {
> + dev_err(dev, "unknown charge type: %s", type_val);
> + return -1;
> + }
> +
> + ret = of_property_read_u32(node, "min-milliamp", &data->min_milliamp);
> + if (ret) {
> + dev_err(dev, "failed to get min-milliamp data: %d", ret);
> + return ret;
> + }
> +
> + ret = of_property_read_u32(node, "max-milliamp", &data->max_milliamp);
> + if (ret) {
> + dev_err(dev, "failed to get max-milliamp data: %d", ret);
> + return ret;
> + }
> +
> + data->ec_dev = cros_ec;
> + data->dev = dev;
> +
> + cdev = devm_thermal_of_cooling_device_register(
> + dev, node, node->name, data,
> + &cros_ec_charge_state_cooling_device_ops);
> + if (IS_ERR_VALUE(cdev)) {
> + dev_err(dev,
> + "failed to register charge chip %s as cooling device: %pe",
> + node->name, cdev);
> + return PTR_ERR(cdev);
> + }
> +
> + return 0;
> +}
> +
> +static int cros_ec_charge_state_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent);
> + struct cros_ec_device *cros_ec = ec_dev->ec_dev;
> + struct device_node *child;
> +
> + for_each_available_child_of_node(cros_ec->dev->of_node, child) {
> + if (!of_device_is_compatible(child,
> + "google,cros-ec-charge-state"))
> + continue;
> + if (cros_ec_charge_state_register_charge_chip(dev, child,
> + cros_ec))
> + continue;
> + }
If no chips are matched -ENODEV would be better.
And errors should be reported from probe().
Given that this is only useable with OF configuration, would it make
more sense to probe it via OF instead of MFD?
> +
> + return 0;
> +}
> +
> +static const struct platform_device_id cros_ec_charge_state_id[] = {
> + { DRV_NAME, 0 },
> + {}
> +};
Reference this in the platform_driver below.
> +static struct platform_driver cros_ec_chargedev_driver = {
> + .driver = {
> + .name = DRV_NAME,
> + },
> + .probe = cros_ec_charge_state_probe,
> +};
> +
> +module_platform_driver(cros_ec_chargedev_driver);
> +
> +MODULE_DEVICE_TABLE(platform, cros_ec_charge_state_id);
> +MODULE_DESCRIPTION("ChromeOS EC Charge State Driver");
> +MODULE_AUTHOR("Sung-Chi, Li <lschyi@chromium.org>");
> +MODULE_LICENSE("GPL");
>
> --
> 2.47.0.338.g60cca15819-goog
>
On 21/11/2024 14:47, Thomas Weißschuh wrote:
>
>> +
>> + return 0;
>> +}
>> +
>> +static const struct platform_device_id cros_ec_charge_state_id[] = {
>> + { DRV_NAME, 0 },
>> + {}
>> +};
>
> Reference this in the platform_driver below.
And missing module device table... This wasn't ever tested as module.
Best regards,
Krzysztof
On 2024-11-21 15:00:13+0100, Krzysztof Kozlowski wrote:
> On 21/11/2024 14:47, Thomas Weißschuh wrote:
> >
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static const struct platform_device_id cros_ec_charge_state_id[] = {
> >> + { DRV_NAME, 0 },
> >> + {}
> >> +};
> >
> > Reference this in the platform_driver below.
>
> And missing module device table... This wasn't ever tested as module.
It has one in the general MODULE_*() macro soup at the end of the file.
But yes, it should be moved where it can be found, right after
cros_ec_charge_state_id.
On Thu, Nov 21, 2024 at 03:11:30PM +0100, Thomas Weißschuh wrote:
> On 2024-11-21 15:00:13+0100, Krzysztof Kozlowski wrote:
> > On 21/11/2024 14:47, Thomas Weißschuh wrote:
> > >
> > >> +
> > >> + return 0;
> > >> +}
> > >> +
> > >> +static const struct platform_device_id cros_ec_charge_state_id[] = {
> > >> + { DRV_NAME, 0 },
> > >> + {}
> > >> +};
> > >
> > > Reference this in the platform_driver below.
> >
> > And missing module device table... This wasn't ever tested as module.
>
> It has one in the general MODULE_*() macro soup at the end of the file.
> But yes, it should be moved where it can be found, right after
> cros_ec_charge_state_id.
Thank you all for spending time reviewing my changes, and I am very sorry that
I made so such careless mistakes. All these input are very valuable, and I
learnt a lot from them, and I will prevent these mistakes in future commits.
As we have seen lots of inputs from the DTS change commit, and I spent lot of
time coming up a better solution for achieving my goal (export certain
mechanisms, such that we can limit the charger chip current as a cooling
device), I think maybe extending functionalities in the
driver/power/supply/cros_usbpd-charger.c would be a better approach. As a
result, I will stop the development on this series. So anyone is helping on this
series can stop review these changes.
However, because I am kind of new to developing the kernel driver module, any
inputs are welcome, and I have to say I really learnt a lot from mistakes
pointed by all of you, and I shall not make same mistakes in future
contributions.
Best,
Sung-Chi Li
Hi Li,
kernel test robot noticed the following build warnings:
[auto build test WARNING on lee-mfd/for-mfd-next]
[also build test WARNING on robh/for-next groeck-staging/hwmon-next chrome-platform/for-next chrome-platform/for-firmware-next lee-mfd/for-mfd-fixes linus/master v6.12 next-20241121]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Sung-Chi-Li/platform-chrome-cros_ec_charge_state-add-new-driver-to-control-charge/20241121-112442
base: https://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd.git for-mfd-next
patch link: https://lore.kernel.org/r/20241118-add_charger_state-v1-1-94997079f35a%40chromium.org
patch subject: [PATCH 1/3] platform/chrome: cros_ec_charge_state: add new driver to control charge
config: m68k-allyesconfig (https://download.01.org/0day-ci/archive/20241121/202411212036.M5ujDUNV-lkp@intel.com/config)
compiler: m68k-linux-gcc (GCC) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241121/202411212036.M5ujDUNV-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202411212036.M5ujDUNV-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> drivers/platform/chrome/cros_ec_charge_state.c:198:40: warning: 'cros_ec_charge_state_id' defined but not used [-Wunused-const-variable=]
198 | static const struct platform_device_id cros_ec_charge_state_id[] = {
| ^~~~~~~~~~~~~~~~~~~~~~~
vim +/cros_ec_charge_state_id +198 drivers/platform/chrome/cros_ec_charge_state.c
197
> 198 static const struct platform_device_id cros_ec_charge_state_id[] = {
199 { DRV_NAME, 0 },
200 {}
201 };
202
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
On Mon, Nov 18, 2024 at 05:33:46PM +0800, Sung-Chi, Li wrote:
> diff --git a/drivers/platform/chrome/cros_ec_charge_state.c b/drivers/platform/chrome/cros_ec_charge_state.c
[...]
> +#define DRV_NAME "cros-ec-charge-state"
> +#define CHARGE_TYPE_CHARGE "charge"
> +#define CHARGE_TYPE_INPUT "input"
I'm not a big fan of these kind of macros and would prefer to remove them.
> +static int
> +cros_ec_charge_state_get_current_limit(struct cros_ec_device *ec_dev,
> + enum charge_state_params charge_type,
> + uint32_t *limit)
> +{
[...]
> + *limit = cpu_to_le32(state.get_param.value);
> + return 0;
> +}
> +
> +static int
> +cros_ec_charge_state_set_current_limit(struct cros_ec_device *ec_dev,
> + enum charge_state_params charge_type,
> + uint32_t limit)
> +{
[...]
> + param.set_param.value = cpu_to_le32(limit);
Looks weird to me. Both getter and setter use cpu_to_le32()? Should one
of them be le32_to_cpu()?
> +static int
> +cros_ec_charge_state_get_cur_state(struct thermal_cooling_device *cdev,
> + unsigned long *state)
> +{
> + struct cros_ec_charge_state_data *data = cdev->devdata;
> + uint32_t limit;
> + int ret;
> +
> + ret = cros_ec_charge_state_get_current_limit(data->ec_dev,
> + data->charge_type, &limit);
> + if (ret) {
> + dev_err(data->dev, "failed to get current state: %d", ret);
If something went wrong, and cros_ec_charge_state_get_current_limit() keeps
returning errors, would it somehow flood the kernel logs?
> + return ret;
> + }
> +
> + *state = data->max_milliamp - limit;
Would it happen: data->max_milliamp - limit < data->min_milliamp == true?
> +static int
> +cros_ec_charge_state_register_charge_chip(struct device *dev,
> + struct device_node *node,
> + struct cros_ec_device *cros_ec)
> +{
[...]
> +
> + if (!strcmp(type_val, CHARGE_TYPE_CHARGE)) {
> + data->charge_type = CS_PARAM_CHG_CURRENT;
> + } else if (!strcmp(type_val, CHARGE_TYPE_INPUT)) {
> + data->charge_type = CS_PARAM_CHG_INPUT_CURRENT;
> + } else {
> + dev_err(dev, "unknown charge type: %s", type_val);
> + return -1;
How about -EINVAL?
> + }
> +
> + ret = of_property_read_u32(node, "min-milliamp", &data->min_milliamp);
> + if (ret) {
> + dev_err(dev, "failed to get min-milliamp data: %d", ret);
> + return ret;
> + }
> +
> + ret = of_property_read_u32(node, "max-milliamp", &data->max_milliamp);
> + if (ret) {
> + dev_err(dev, "failed to get max-milliamp data: %d", ret);
> + return ret;
> + }
Would it happen: min-milliamp > max-milliamp == true?
> +
> + data->ec_dev = cros_ec;
> + data->dev = dev;
> +
> + cdev = devm_thermal_of_cooling_device_register(
> + dev, node, node->name, data,
> + &cros_ec_charge_state_cooling_device_ops);
> + if (IS_ERR_VALUE(cdev)) {
Any reasons to not use IS_ERR()?
> +static int cros_ec_charge_state_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent);
> + struct cros_ec_device *cros_ec = ec_dev->ec_dev;
> + struct device_node *child;
> +
> + for_each_available_child_of_node(cros_ec->dev->of_node, child) {
> + if (!of_device_is_compatible(child,
> + "google,cros-ec-charge-state"))
> + continue;
> + if (cros_ec_charge_state_register_charge_chip(dev, child,
> + cros_ec))
> + continue;
> + }
There should be a way to use the compatible string in struct mfd_cell for
matching the node. See also [1].
[1]: https://elixir.bootlin.com/linux/v6.12/source/drivers/mfd/mfd-core.c#L184
> +
> +static const struct platform_device_id cros_ec_charge_state_id[] = {
> + { DRV_NAME, 0 },
^
> +static struct platform_driver cros_ec_chargedev_driver = {
The whole file uses "cros_ec_charge_state_" as a prefix for all symbols. Any
reasons to not make this consistent?
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