[PATCH v5 1/2] platform: chrome: Add cros-usbpd-notify driver

[PATCH v5 1/2] platform: chrome: Add cros-usbpd-notify driver

[Prashant Malani]

From: Jon Flatley <jflat@chromium.org>

ChromiumOS uses ACPI device with HID "GOOG0003" for power delivery
related events. The existing cros-usbpd-charger driver relies on these
events without ever actually receiving them on ACPI platforms. This is
because in the ChromeOS kernel trees, the GOOG0003 device is owned by an
ACPI driver that offers firmware updates to USB-C chargers.

Introduce a new platform driver under cros-ec, the ChromeOS embedded
controller, that handles these PD events and dispatches them
appropriately over a notifier chain to all drivers that use them.

On platforms that don't have the ACPI device defined, the driver gets
instantiated for ECs which support the EC_FEATURE_USB_PD feature bit,
and the notification events will get delivered using the MKBP event
handling mechanism.

Co-Developed-by: Prashant Malani <pmalani@chromium.org>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Jon Flatley <jflat@chromium.org>
Signed-off-by: Prashant Malani <pmalani@chromium.org>
---

Changes in v5(pmalani@chromium.org):
- Split the driver into platform and ACPI variants, each enclosed by
  CONFIG_OF and CONFIG_ACPI #ifdefs respectively.
- Updated the copyright year to 2020.
- Reworded the commit message and Kconfig description to incorporate
  the modified driver structure.

Changes in v4(pmalani@chromium.org):
- No code changes, but added new version so that versioning is
  consistent with the next patch in the series.

Changes in v3 (pmalani@chromium.org):
- Renamed driver and files from "cros_ec_pd_notify" to
  "cros_usbpd_notify" to be more consistent with other naming.
- Moved the change to include cros-usbpd-notify in the charger MFD
  into a separate follow-on patch.

Changes in v2 (pmalani@chromium.org):
- Removed dependency on DT entry; instead, we will instantiate
  the driver on detecting EC_FEATURE_USB_PD for non-ACPI platforms.
- Modified the cros-ec-pd-notify device to be an mfd_cell under
  usbpdcharger for non-ACPI platforms. Altered the platform_probe() call
  to derive the cros EC structs appropriately.
- Replaced "usbpd_notify" with "pd_notify" in functions and structures.
- Addressed comments from upstream maintainer.

 drivers/platform/chrome/Kconfig               |  10 ++
 drivers/platform/chrome/Makefile              |   1 +
 drivers/platform/chrome/cros_usbpd_notify.c   | 153 ++++++++++++++++++
 .../linux/platform_data/cros_usbpd_notify.h   |  17 ++
 4 files changed, 181 insertions(+)
 create mode 100644 drivers/platform/chrome/cros_usbpd_notify.c
 create mode 100644 include/linux/platform_data/cros_usbpd_notify.h

diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig
index 5f57282a28da0..89df6c991089d 100644
--- a/drivers/platform/chrome/Kconfig
+++ b/drivers/platform/chrome/Kconfig
@@ -226,6 +226,16 @@ config CROS_USBPD_LOGGER
 	  To compile this driver as a module, choose M here: the
 	  module will be called cros_usbpd_logger.
 
+config CROS_USBPD_NOTIFY
+	tristate "ChromeOS Type-C power delivery event notifier"
+	depends on CROS_EC
+	help
+	  If you say Y here, you get support for Type-C PD event notifications
+	  from the ChromeOS EC. On ACPI platorms this driver will bind to the
+	  GOOG0003 ACPI device, and on platforms which don't have this device it
+	  will get initialized on ECs which support the feature
+	  EC_FEATURE_USB_PD.
+
 source "drivers/platform/chrome/wilco_ec/Kconfig"
 
 endif # CHROMEOS_PLATFORMS
diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile
index aacd5920d8a18..f6465f8ef0b5e 100644
--- a/drivers/platform/chrome/Makefile
+++ b/drivers/platform/chrome/Makefile
@@ -22,5 +22,6 @@ obj-$(CONFIG_CROS_EC_DEBUGFS)		+= cros_ec_debugfs.o
 obj-$(CONFIG_CROS_EC_SENSORHUB)		+= cros_ec_sensorhub.o
 obj-$(CONFIG_CROS_EC_SYSFS)		+= cros_ec_sysfs.o
 obj-$(CONFIG_CROS_USBPD_LOGGER)		+= cros_usbpd_logger.o
+obj-$(CONFIG_CROS_USBPD_NOTIFY)		+= cros_usbpd_notify.o
 
 obj-$(CONFIG_WILCO_EC)			+= wilco_ec/
diff --git a/drivers/platform/chrome/cros_usbpd_notify.c b/drivers/platform/chrome/cros_usbpd_notify.c
new file mode 100644
index 0000000000000..1c4f690bd7746
--- /dev/null
+++ b/drivers/platform/chrome/cros_usbpd_notify.c
@@ -0,0 +1,153 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2020 Google LLC
+ *
+ * This driver serves as the receiver of cros_ec PD host events.
+ */
+
+#include <linux/acpi.h>
+#include <linux/module.h>
+#include <linux/mfd/cros_ec.h>
+#include <linux/platform_data/cros_ec_commands.h>
+#include <linux/platform_data/cros_usbpd_notify.h>
+#include <linux/platform_data/cros_ec_proto.h>
+#include <linux/platform_device.h>
+
+#define DRV_NAME "cros-usbpd-notify"
+#define ACPI_DRV_NAME "GOOG0003"
+
+static BLOCKING_NOTIFIER_HEAD(cros_usbpd_notifier_list);
+
+/**
+ * cros_usbpd_register_notify - Register a notifier callback for PD events.
+ * @nb: Notifier block pointer to register
+ *
+ * On ACPI platforms this corresponds to host events on the ECPD
+ * "GOOG0003" ACPI device. On non-ACPI platforms this will filter mkbp events
+ * for USB PD events.
+ *
+ * Return: 0 on success or negative error code.
+ */
+int cros_usbpd_register_notify(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(
+			&cros_usbpd_notifier_list, nb);
+}
+EXPORT_SYMBOL_GPL(cros_usbpd_register_notify);
+
+
+/**
+ * cros_usbpd_unregister_notify - Unregister notifier callback for PD events.
+ * @nb: Notifier block pointer to unregister
+ *
+ * Unregister a notifier callback that was previously registered with
+ * cros_usbpd_register_notify().
+ */
+void cros_usbpd_unregister_notify(struct notifier_block *nb)
+{
+	blocking_notifier_chain_unregister(&cros_usbpd_notifier_list, nb);
+}
+EXPORT_SYMBOL_GPL(cros_usbpd_unregister_notify);
+
+#ifdef CONFIG_ACPI
+
+static int cros_usbpd_notify_add_acpi(struct acpi_device *adev)
+{
+	return 0;
+}
+
+static void cros_usbpd_notify_acpi(struct acpi_device *adev, u32 event)
+{
+	blocking_notifier_call_chain(&cros_usbpd_notifier_list, event, NULL);
+}
+
+static const struct acpi_device_id cros_usbpd_notify_acpi_device_ids[] = {
+	{ ACPI_DRV_NAME, 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(acpi, cros_usbpd_acpi_device_ids);
+
+static struct acpi_driver cros_usbpd_notify_acpi_driver = {
+	.name = DRV_NAME,
+	.class = DRV_NAME,
+	.ids = cros_usbpd_notify_acpi_device_ids,
+	.ops = {
+		.add = cros_usbpd_notify_add_acpi,
+		.notify = cros_usbpd_notify_acpi,
+	},
+};
+module_acpi_driver(cros_usbpd_notify_acpi_driver);
+
+#endif /* CONFIG_ACPI */
+
+#ifdef CONFIG_OF
+
+static int cros_usbpd_notify_plat(struct notifier_block *nb,
+		unsigned long queued_during_suspend, void *data)
+{
+	struct cros_ec_device *ec_dev = (struct cros_ec_device *)data;
+	u32 host_event = cros_ec_get_host_event(ec_dev);
+
+	if (!host_event)
+		return NOTIFY_BAD;
+
+	if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU)) {
+		blocking_notifier_call_chain(&cros_usbpd_notifier_list,
+				host_event, NULL);
+		return NOTIFY_OK;
+	}
+	return NOTIFY_DONE;
+}
+
+static int cros_usbpd_notify_probe_plat(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent);
+	struct notifier_block *nb;
+	int ret;
+
+	nb = devm_kzalloc(dev, sizeof(*nb), GFP_KERNEL);
+	if (!nb)
+		return -ENOMEM;
+
+	nb->notifier_call = cros_usbpd_notify_plat;
+	dev_set_drvdata(dev, nb);
+
+	ret = blocking_notifier_chain_register(&ecdev->ec_dev->event_notifier,
+						nb);
+	if (ret < 0) {
+		dev_err(dev, "Failed to register notifier\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int cros_usbpd_notify_remove_plat(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent);
+	struct notifier_block *nb =
+		(struct notifier_block *)dev_get_drvdata(dev);
+
+	blocking_notifier_chain_unregister(&ecdev->ec_dev->event_notifier,
+			nb);
+
+	return 0;
+}
+
+static struct platform_driver cros_usbpd_notify_plat_driver = {
+	.driver = {
+		.name = DRV_NAME,
+	},
+	.probe = cros_usbpd_notify_probe_plat,
+	.remove = cros_usbpd_notify_remove_plat,
+};
+module_platform_driver(cros_usbpd_notify_plat_driver);
+
+#endif /* CONFIG_OF */
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("ChromeOS power delivery notifier device");
+MODULE_AUTHOR("Jon Flatley <jflat@chromium.org>");
+MODULE_ALIAS("platform:" DRV_NAME);
diff --git a/include/linux/platform_data/cros_usbpd_notify.h b/include/linux/platform_data/cros_usbpd_notify.h
new file mode 100644
index 0000000000000..4f2791722b6d3
--- /dev/null
+++ b/include/linux/platform_data/cros_usbpd_notify.h
@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ChromeOS EC Power Delivery Notifier Driver
+ *
+ * Copyright 2020 Google LLC
+ */
+
+#ifndef __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H
+#define __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H
+
+#include <linux/notifier.h>
+
+int cros_usbpd_register_notify(struct notifier_block *nb);
+
+void cros_usbpd_unregister_notify(struct notifier_block *nb);
+
+#endif  /* __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H */
-- 
2.25.0.rc1.283.g88dfdc4193-goog

[PATCH v5 2/2] mfd: cros_ec: Add cros-usbpd-notify subdevice

[Prashant Malani]

Add the cros-usbpd-notify driver as a subdevice on platforms that
support the EC_FEATURE_USB_PD EC feature flag and don't have the
ACPI PD notification device defined.

This driver allows other cros-ec devices to receive PD event
notifications from the Chrome OS Embedded Controller (EC) via a
notification chain.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
---

Changes in v5:
- Updated the IS_ENABLED() check to check for CONFIG_OF instead of
  !CONFIG_ACPI according to upstream comments.

Changes in v4:
- Removed #ifndef usage; instead, moved cros-usbpd-notify to a separate
  mfd_cell and used an IS_ENABLED() check.
- Changed commit title and description slightly to reflect change in
  code.

 drivers/mfd/cros_ec_dev.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c
index c4b977a5dd966..d0c28a4c10ad0 100644
--- a/drivers/mfd/cros_ec_dev.c
+++ b/drivers/mfd/cros_ec_dev.c
@@ -5,6 +5,7 @@
  * Copyright (C) 2014 Google, Inc.
  */
 
+#include <linux/kconfig.h>
 #include <linux/mfd/core.h>
 #include <linux/mfd/cros_ec.h>
 #include <linux/module.h>
@@ -87,6 +88,10 @@ static const struct mfd_cell cros_usbpd_charger_cells[] = {
 	{ .name = "cros-usbpd-logger", },
 };
 
+static const struct mfd_cell cros_usbpd_notify_cells[] = {
+	{ .name = "cros-usbpd-notify", },
+};
+
 static const struct cros_feature_to_cells cros_subdevices[] = {
 	{
 		.id		= EC_FEATURE_CEC,
@@ -202,6 +207,23 @@ static int ec_device_probe(struct platform_device *pdev)
 		}
 	}
 
+	/*
+	 * The PD notifier driver cell is separate since it only needs to be
+	 * explicitly added on platforms that don't have the PD notifier ACPI
+	 * device entry defined.
+	 */
+	if (IS_ENABLED(CONFIG_OF)) {
+		if (cros_ec_check_features(ec, EC_FEATURE_USB_PD)) {
+			retval = mfd_add_hotplug_devices(ec->dev,
+					cros_usbpd_notify_cells,
+					ARRAY_SIZE(cros_usbpd_notify_cells));
+			if (retval)
+				dev_err(ec->dev,
+					"failed to add PD notify devices: %d\n",
+					retval);
+		}
+	}
+
 	/*
 	 * The following subdevices cannot be detected by sending the
 	 * EC_FEATURE_GET_CMD to the Embedded Controller device.
-- 
2.25.0.rc1.283.g88dfdc4193-goog

Re: [PATCH v5 1/2] platform: chrome: Add cros-usbpd-notify driver

[Enric Balletbo i Serra]

Hi Prashant,

On 14/1/20 4:10, Prashant Malani wrote:
> From: Jon Flatley <jflat@chromium.org>
> 
> ChromiumOS uses ACPI device with HID "GOOG0003" for power delivery
> related events. The existing cros-usbpd-charger driver relies on these
> events without ever actually receiving them on ACPI platforms. This is
> because in the ChromeOS kernel trees, the GOOG0003 device is owned by an
> ACPI driver that offers firmware updates to USB-C chargers.
> 
> Introduce a new platform driver under cros-ec, the ChromeOS embedded
> controller, that handles these PD events and dispatches them
> appropriately over a notifier chain to all drivers that use them.
> 
> On platforms that don't have the ACPI device defined, the driver gets
> instantiated for ECs which support the EC_FEATURE_USB_PD feature bit,
> and the notification events will get delivered using the MKBP event
> handling mechanism.
> 
> Co-Developed-by: Prashant Malani <pmalani@chromium.org>
> Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
> Signed-off-by: Jon Flatley <jflat@chromium.org>
> Signed-off-by: Prashant Malani <pmalani@chromium.org>
> ---
> 
> Changes in v5(pmalani@chromium.org):
> - Split the driver into platform and ACPI variants, each enclosed by
>   CONFIG_OF and CONFIG_ACPI #ifdefs respectively.
> - Updated the copyright year to 2020.
> - Reworded the commit message and Kconfig description to incorporate
>   the modified driver structure.
> 
> Changes in v4(pmalani@chromium.org):
> - No code changes, but added new version so that versioning is
>   consistent with the next patch in the series.
> 
> Changes in v3 (pmalani@chromium.org):
> - Renamed driver and files from "cros_ec_pd_notify" to
>   "cros_usbpd_notify" to be more consistent with other naming.
> - Moved the change to include cros-usbpd-notify in the charger MFD
>   into a separate follow-on patch.
> 
> Changes in v2 (pmalani@chromium.org):
> - Removed dependency on DT entry; instead, we will instantiate
>   the driver on detecting EC_FEATURE_USB_PD for non-ACPI platforms.
> - Modified the cros-ec-pd-notify device to be an mfd_cell under
>   usbpdcharger for non-ACPI platforms. Altered the platform_probe() call
>   to derive the cros EC structs appropriately.
> - Replaced "usbpd_notify" with "pd_notify" in functions and structures.
> - Addressed comments from upstream maintainer.
> 
>  drivers/platform/chrome/Kconfig               |  10 ++
>  drivers/platform/chrome/Makefile              |   1 +
>  drivers/platform/chrome/cros_usbpd_notify.c   | 153 ++++++++++++++++++
>  .../linux/platform_data/cros_usbpd_notify.h   |  17 ++
>  4 files changed, 181 insertions(+)
>  create mode 100644 drivers/platform/chrome/cros_usbpd_notify.c
>  create mode 100644 include/linux/platform_data/cros_usbpd_notify.h
> 
> diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig
> index 5f57282a28da0..89df6c991089d 100644
> --- a/drivers/platform/chrome/Kconfig
> +++ b/drivers/platform/chrome/Kconfig
> @@ -226,6 +226,16 @@ config CROS_USBPD_LOGGER
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called cros_usbpd_logger.
>  
> +config CROS_USBPD_NOTIFY
> +	tristate "ChromeOS Type-C power delivery event notifier"
> +	depends on CROS_EC
> +	help
> +	  If you say Y here, you get support for Type-C PD event notifications
> +	  from the ChromeOS EC. On ACPI platorms this driver will bind to the
> +	  GOOG0003 ACPI device, and on platforms which don't have this device it
> +	  will get initialized on ECs which support the feature
> +	  EC_FEATURE_USB_PD.
> +
>  source "drivers/platform/chrome/wilco_ec/Kconfig"
>  
>  endif # CHROMEOS_PLATFORMS
> diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile
> index aacd5920d8a18..f6465f8ef0b5e 100644
> --- a/drivers/platform/chrome/Makefile
> +++ b/drivers/platform/chrome/Makefile
> @@ -22,5 +22,6 @@ obj-$(CONFIG_CROS_EC_DEBUGFS)		+= cros_ec_debugfs.o
>  obj-$(CONFIG_CROS_EC_SENSORHUB)		+= cros_ec_sensorhub.o
>  obj-$(CONFIG_CROS_EC_SYSFS)		+= cros_ec_sysfs.o
>  obj-$(CONFIG_CROS_USBPD_LOGGER)		+= cros_usbpd_logger.o
> +obj-$(CONFIG_CROS_USBPD_NOTIFY)		+= cros_usbpd_notify.o
>  
>  obj-$(CONFIG_WILCO_EC)			+= wilco_ec/
> diff --git a/drivers/platform/chrome/cros_usbpd_notify.c b/drivers/platform/chrome/cros_usbpd_notify.c
> new file mode 100644
> index 0000000000000..1c4f690bd7746
> --- /dev/null
> +++ b/drivers/platform/chrome/cros_usbpd_notify.c
> @@ -0,0 +1,153 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright 2020 Google LLC
> + *
> + * This driver serves as the receiver of cros_ec PD host events.
> + */
> +
> +#include <linux/acpi.h>
> +#include <linux/module.h>
> +#include <linux/mfd/cros_ec.h>
> +#include <linux/platform_data/cros_ec_commands.h>
> +#include <linux/platform_data/cros_usbpd_notify.h>
> +#include <linux/platform_data/cros_ec_proto.h>
> +#include <linux/platform_device.h>
> +
> +#define DRV_NAME "cros-usbpd-notify"
> +#define ACPI_DRV_NAME "GOOG0003"
> +
> +static BLOCKING_NOTIFIER_HEAD(cros_usbpd_notifier_list);
> +
> +/**
> + * cros_usbpd_register_notify - Register a notifier callback for PD events.
> + * @nb: Notifier block pointer to register
> + *
> + * On ACPI platforms this corresponds to host events on the ECPD
> + * "GOOG0003" ACPI device. On non-ACPI platforms this will filter mkbp events
> + * for USB PD events.
> + *
> + * Return: 0 on success or negative error code.
> + */
> +int cros_usbpd_register_notify(struct notifier_block *nb)
> +{
> +	return blocking_notifier_chain_register(
> +			&cros_usbpd_notifier_list, nb);
> +}
> +EXPORT_SYMBOL_GPL(cros_usbpd_register_notify);
> +
> +
> +/**
> + * cros_usbpd_unregister_notify - Unregister notifier callback for PD events.
> + * @nb: Notifier block pointer to unregister
> + *
> + * Unregister a notifier callback that was previously registered with
> + * cros_usbpd_register_notify().
> + */
> +void cros_usbpd_unregister_notify(struct notifier_block *nb)
> +{
> +	blocking_notifier_chain_unregister(&cros_usbpd_notifier_list, nb);
> +}
> +EXPORT_SYMBOL_GPL(cros_usbpd_unregister_notify);
> +
> +#ifdef CONFIG_ACPI
> +
> +static int cros_usbpd_notify_add_acpi(struct acpi_device *adev)
> +{
> +	return 0;
> +}
> +
> +static void cros_usbpd_notify_acpi(struct acpi_device *adev, u32 event)
> +{
> +	blocking_notifier_call_chain(&cros_usbpd_notifier_list, event, NULL);
> +}
> +
> +static const struct acpi_device_id cros_usbpd_notify_acpi_device_ids[] = {
> +	{ ACPI_DRV_NAME, 0 },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(acpi, cros_usbpd_acpi_device_ids);
Ops, there is a build error here, please make sure to build the driver before
sending.

s/cros_usbpd_acpi_device_ids/cros_usbpd_notify_acpi_device_ids/

Apart from this I'm getting build errors with my defconfig which has CONFIG_ACPI
and CONFIG_OF enabled.

Another problem that I have with this driver is that actually there is no user
for it. I'd really prefer have this included on a series that also introduces
the user of this notifier. If you are only testing the ACPI case you can focus
first on this use case and we add later the OF case (maybe is an easy way to
proceed).

Thanks,
 Enric

> +
> +static struct acpi_driver cros_usbpd_notify_acpi_driver = {
> +	.name = DRV_NAME,
> +	.class = DRV_NAME,
> +	.ids = cros_usbpd_notify_acpi_device_ids,
> +	.ops = {
> +		.add = cros_usbpd_notify_add_acpi,
> +		.notify = cros_usbpd_notify_acpi,
> +	},
> +};
> +module_acpi_driver(cros_usbpd_notify_acpi_driver);
> +
> +#endif /* CONFIG_ACPI */
> +
> +#ifdef CONFIG_OF
> +
> +static int cros_usbpd_notify_plat(struct notifier_block *nb,
> +		unsigned long queued_during_suspend, void *data)
> +{
> +	struct cros_ec_device *ec_dev = (struct cros_ec_device *)data;
> +	u32 host_event = cros_ec_get_host_event(ec_dev);
> +
> +	if (!host_event)
> +		return NOTIFY_BAD;
> +
> +	if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU)) {
> +		blocking_notifier_call_chain(&cros_usbpd_notifier_list,
> +				host_event, NULL);
> +		return NOTIFY_OK;
> +	}
> +	return NOTIFY_DONE;
> +}
> +
> +static int cros_usbpd_notify_probe_plat(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent);
> +	struct notifier_block *nb;
> +	int ret;
> +
> +	nb = devm_kzalloc(dev, sizeof(*nb), GFP_KERNEL);
> +	if (!nb)
> +		return -ENOMEM;
> +
> +	nb->notifier_call = cros_usbpd_notify_plat;
> +	dev_set_drvdata(dev, nb);
> +
> +	ret = blocking_notifier_chain_register(&ecdev->ec_dev->event_notifier,
> +						nb);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to register notifier\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int cros_usbpd_notify_remove_plat(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent);
> +	struct notifier_block *nb =
> +		(struct notifier_block *)dev_get_drvdata(dev);
> +
> +	blocking_notifier_chain_unregister(&ecdev->ec_dev->event_notifier,
> +			nb);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver cros_usbpd_notify_plat_driver = {
> +	.driver = {
> +		.name = DRV_NAME,
> +	},
> +	.probe = cros_usbpd_notify_probe_plat,
> +	.remove = cros_usbpd_notify_remove_plat,
> +};
> +module_platform_driver(cros_usbpd_notify_plat_driver);
> +
> +#endif /* CONFIG_OF */
> +
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("ChromeOS power delivery notifier device");
> +MODULE_AUTHOR("Jon Flatley <jflat@chromium.org>");
> +MODULE_ALIAS("platform:" DRV_NAME);
> diff --git a/include/linux/platform_data/cros_usbpd_notify.h b/include/linux/platform_data/cros_usbpd_notify.h
> new file mode 100644
> index 0000000000000..4f2791722b6d3
> --- /dev/null
> +++ b/include/linux/platform_data/cros_usbpd_notify.h
> @@ -0,0 +1,17 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * ChromeOS EC Power Delivery Notifier Driver
> + *
> + * Copyright 2020 Google LLC
> + */
> +
> +#ifndef __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H
> +#define __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H
> +
> +#include <linux/notifier.h>
> +
> +int cros_usbpd_register_notify(struct notifier_block *nb);
> +
> +void cros_usbpd_unregister_notify(struct notifier_block *nb);
> +
> +#endif  /* __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H */
> 

Re: [PATCH v5 1/2] platform: chrome: Add cros-usbpd-notify driver

[Prashant Malani]

On Tue, Jan 14, 2020 at 9:07 AM Enric Balletbo i Serra
<enric.balletbo@collabora.com> wrote:
>
> Hi Prashant,
>
> On 14/1/20 4:10, Prashant Malani wrote:
> > From: Jon Flatley <jflat@chromium.org>
> > +};
> > +MODULE_DEVICE_TABLE(acpi, cros_usbpd_acpi_device_ids);
> Ops, there is a build error here, please make sure to build the driver before
> sending.
Hmm. That's odd, I did check  using arm64 defconfig. My apologies.
Could you kindly share your build commands so that I can use this
going forward?
>
> s/cros_usbpd_acpi_device_ids/cros_usbpd_notify_acpi_device_ids/
>
> Apart from this I'm getting build errors with my defconfig which has CONFIG_ACPI
> and CONFIG_OF enabled.
>
> Another problem that I have with this driver is that actually there is no user
> for it. I'd really prefer have this included on a series that also introduces
> the user of this notifier. If you are only testing the ACPI case you can focus
> first on this use case and we add later the OF case (maybe is an easy way to
> proceed).
I'm testing with an arm64 device too locally. I will try to
incorporate the new change which updates cros_usbpd-charger to use the
notifier mechanism. I think we can try for the OF case simultaneously
(it is probably just the build errors I need to check for)

Thanks again!
>
> Thanks,
>  Enric
>
> > +
> > +static struct acpi_driver cros_usbpd_notify_acpi_driver = {
> > +     .name = DRV_NAME,
> > +     .class = DRV_NAME,
> > +     .ids = cros_usbpd_notify_acpi_device_ids,
> > +     .ops = {
> > +             .add = cros_usbpd_notify_add_acpi,
> > +             .notify = cros_usbpd_notify_acpi,
> > +     },
> > +};
> > +module_acpi_driver(cros_usbpd_notify_acpi_driver);
> > +
> > +#endif /* CONFIG_ACPI */
> > +
> > +#ifdef CONFIG_OF
> > +
> > +static int cros_usbpd_notify_plat(struct notifier_block *nb,
> > +             unsigned long queued_during_suspend, void *data)
> > +{
> > +     struct cros_ec_device *ec_dev = (struct cros_ec_device *)data;
> > +     u32 host_event = cros_ec_get_host_event(ec_dev);
> > +
> > +     if (!host_event)
> > +             return NOTIFY_BAD;
> > +
> > +     if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU)) {
> > +             blocking_notifier_call_chain(&cros_usbpd_notifier_list,
> > +                             host_event, NULL);
> > +             return NOTIFY_OK;
> > +     }
> > +     return NOTIFY_DONE;
> > +}
> > +
> > +static int cros_usbpd_notify_probe_plat(struct platform_device *pdev)
> > +{
> > +     struct device *dev = &pdev->dev;
> > +     struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent);
> > +     struct notifier_block *nb;
> > +     int ret;
> > +
> > +     nb = devm_kzalloc(dev, sizeof(*nb), GFP_KERNEL);
> > +     if (!nb)
> > +             return -ENOMEM;
> > +
> > +     nb->notifier_call = cros_usbpd_notify_plat;
> > +     dev_set_drvdata(dev, nb);
> > +
> > +     ret = blocking_notifier_chain_register(&ecdev->ec_dev->event_notifier,
> > +                                             nb);
> > +     if (ret < 0) {
> > +             dev_err(dev, "Failed to register notifier\n");
> > +             return ret;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int cros_usbpd_notify_remove_plat(struct platform_device *pdev)
> > +{
> > +     struct device *dev = &pdev->dev;
> > +     struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent);
> > +     struct notifier_block *nb =
> > +             (struct notifier_block *)dev_get_drvdata(dev);
> > +
> > +     blocking_notifier_chain_unregister(&ecdev->ec_dev->event_notifier,
> > +                     nb);
> > +
> > +     return 0;
> > +}
> > +
> > +static struct platform_driver cros_usbpd_notify_plat_driver = {
> > +     .driver = {
> > +             .name = DRV_NAME,
> > +     },
> > +     .probe = cros_usbpd_notify_probe_plat,
> > +     .remove = cros_usbpd_notify_remove_plat,
> > +};
> > +module_platform_driver(cros_usbpd_notify_plat_driver);
> > +
> > +#endif /* CONFIG_OF */
> > +
> > +MODULE_LICENSE("GPL");
> > +MODULE_DESCRIPTION("ChromeOS power delivery notifier device");
> > +MODULE_AUTHOR("Jon Flatley <jflat@chromium.org>");
> > +MODULE_ALIAS("platform:" DRV_NAME);
> > diff --git a/include/linux/platform_data/cros_usbpd_notify.h b/include/linux/platform_data/cros_usbpd_notify.h
> > new file mode 100644
> > index 0000000000000..4f2791722b6d3
> > --- /dev/null
> > +++ b/include/linux/platform_data/cros_usbpd_notify.h
> > @@ -0,0 +1,17 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * ChromeOS EC Power Delivery Notifier Driver
> > + *
> > + * Copyright 2020 Google LLC
> > + */
> > +
> > +#ifndef __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H
> > +#define __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H
> > +
> > +#include <linux/notifier.h>
> > +
> > +int cros_usbpd_register_notify(struct notifier_block *nb);
> > +
> > +void cros_usbpd_unregister_notify(struct notifier_block *nb);
> > +
> > +#endif  /* __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H */
> >

Re: [PATCH v5 1/2] platform: chrome: Add cros-usbpd-notify driver

[Enric Balletbo i Serra]

On 14/1/20 20:23, Prashant Malani wrote:
> On Tue, Jan 14, 2020 at 9:07 AM Enric Balletbo i Serra
> <enric.balletbo@collabora.com> wrote:
>>
>> Hi Prashant,
>>
>> On 14/1/20 4:10, Prashant Malani wrote:
>>> From: Jon Flatley <jflat@chromium.org>
>>> +};
>>> +MODULE_DEVICE_TABLE(acpi, cros_usbpd_acpi_device_ids);
>> Ops, there is a build error here, please make sure to build the driver before
>> sending.
> Hmm. That's odd, I did check  using arm64 defconfig. My apologies.
> Could you kindly share your build commands so that I can use this
> going forward?
>>
>> s/cros_usbpd_acpi_device_ids/cros_usbpd_notify_acpi_device_ids/
>>

one problem is the above^

drivers/platform/chrome/cros_usbpd_notify.c:67:27: error:
‘cros_usbpd_acpi_device_ids’ undeclared here (not in a function); did you mean
‘cros_usbpd_notify_acpi_device_ids’?

The others I didn't dig in. My build commands are the common.

make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- defconfig
# Enable the new cros_usbpd_notify driver
make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- -j4

Cheers,
 Enric

>> Apart from this I'm getting build errors with my defconfig which has CONFIG_ACPI
>> and CONFIG_OF enabled.
>>
>> Another problem that I have with this driver is that actually there is no user
>> for it. I'd really prefer have this included on a series that also introduces
>> the user of this notifier. If you are only testing the ACPI case you can focus
>> first on this use case and we add later the OF case (maybe is an easy way to
>> proceed).
> I'm testing with an arm64 device too locally. I will try to
> incorporate the new change which updates cros_usbpd-charger to use the
> notifier mechanism. I think we can try for the OF case simultaneously
> (it is probably just the build errors I need to check for)
> 
> Thanks again!
>>
>> Thanks,
>>  Enric
>>
>>> +
>>> +static struct acpi_driver cros_usbpd_notify_acpi_driver = {
>>> +     .name = DRV_NAME,
>>> +     .class = DRV_NAME,
>>> +     .ids = cros_usbpd_notify_acpi_device_ids,
>>> +     .ops = {
>>> +             .add = cros_usbpd_notify_add_acpi,
>>> +             .notify = cros_usbpd_notify_acpi,
>>> +     },
>>> +};
>>> +module_acpi_driver(cros_usbpd_notify_acpi_driver);
>>> +
>>> +#endif /* CONFIG_ACPI */
>>> +
>>> +#ifdef CONFIG_OF
>>> +
>>> +static int cros_usbpd_notify_plat(struct notifier_block *nb,
>>> +             unsigned long queued_during_suspend, void *data)
>>> +{
>>> +     struct cros_ec_device *ec_dev = (struct cros_ec_device *)data;
>>> +     u32 host_event = cros_ec_get_host_event(ec_dev);
>>> +
>>> +     if (!host_event)
>>> +             return NOTIFY_BAD;
>>> +
>>> +     if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU)) {
>>> +             blocking_notifier_call_chain(&cros_usbpd_notifier_list,
>>> +                             host_event, NULL);
>>> +             return NOTIFY_OK;
>>> +     }
>>> +     return NOTIFY_DONE;
>>> +}
>>> +
>>> +static int cros_usbpd_notify_probe_plat(struct platform_device *pdev)
>>> +{
>>> +     struct device *dev = &pdev->dev;
>>> +     struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent);
>>> +     struct notifier_block *nb;
>>> +     int ret;
>>> +
>>> +     nb = devm_kzalloc(dev, sizeof(*nb), GFP_KERNEL);
>>> +     if (!nb)
>>> +             return -ENOMEM;
>>> +
>>> +     nb->notifier_call = cros_usbpd_notify_plat;
>>> +     dev_set_drvdata(dev, nb);
>>> +
>>> +     ret = blocking_notifier_chain_register(&ecdev->ec_dev->event_notifier,
>>> +                                             nb);
>>> +     if (ret < 0) {
>>> +             dev_err(dev, "Failed to register notifier\n");
>>> +             return ret;
>>> +     }
>>> +
>>> +     return 0;
>>> +}
>>> +
>>> +static int cros_usbpd_notify_remove_plat(struct platform_device *pdev)
>>> +{
>>> +     struct device *dev = &pdev->dev;
>>> +     struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent);
>>> +     struct notifier_block *nb =
>>> +             (struct notifier_block *)dev_get_drvdata(dev);
>>> +
>>> +     blocking_notifier_chain_unregister(&ecdev->ec_dev->event_notifier,
>>> +                     nb);
>>> +
>>> +     return 0;
>>> +}
>>> +
>>> +static struct platform_driver cros_usbpd_notify_plat_driver = {
>>> +     .driver = {
>>> +             .name = DRV_NAME,
>>> +     },
>>> +     .probe = cros_usbpd_notify_probe_plat,
>>> +     .remove = cros_usbpd_notify_remove_plat,
>>> +};
>>> +module_platform_driver(cros_usbpd_notify_plat_driver);
>>> +
>>> +#endif /* CONFIG_OF */
>>> +
>>> +MODULE_LICENSE("GPL");
>>> +MODULE_DESCRIPTION("ChromeOS power delivery notifier device");
>>> +MODULE_AUTHOR("Jon Flatley <jflat@chromium.org>");
>>> +MODULE_ALIAS("platform:" DRV_NAME);
>>> diff --git a/include/linux/platform_data/cros_usbpd_notify.h b/include/linux/platform_data/cros_usbpd_notify.h
>>> new file mode 100644
>>> index 0000000000000..4f2791722b6d3
>>> --- /dev/null
>>> +++ b/include/linux/platform_data/cros_usbpd_notify.h
>>> @@ -0,0 +1,17 @@
>>> +// SPDX-License-Identifier: GPL-2.0-only
>>> +/*
>>> + * ChromeOS EC Power Delivery Notifier Driver
>>> + *
>>> + * Copyright 2020 Google LLC
>>> + */
>>> +
>>> +#ifndef __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H
>>> +#define __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H
>>> +
>>> +#include <linux/notifier.h>
>>> +
>>> +int cros_usbpd_register_notify(struct notifier_block *nb);
>>> +
>>> +void cros_usbpd_unregister_notify(struct notifier_block *nb);
>>> +
>>> +#endif  /* __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H */
>>>

Re: [PATCH v5 1/2] platform: chrome: Add cros-usbpd-notify driver

[Prashant Malani]

On Tue, Jan 14, 2020 at 12:29 PM Enric Balletbo i Serra
<enric.balletbo@collabora.com> wrote:
>
>
>
> On 14/1/20 20:23, Prashant Malani wrote:
> > On Tue, Jan 14, 2020 at 9:07 AM Enric Balletbo i Serra
> > <enric.balletbo@collabora.com> wrote:
> >>
> >> Hi Prashant,
> >>
> >> On 14/1/20 4:10, Prashant Malani wrote:
> >>> From: Jon Flatley <jflat@chromium.org>
> >>> +};
> >>> +MODULE_DEVICE_TABLE(acpi, cros_usbpd_acpi_device_ids);
> >> Ops, there is a build error here, please make sure to build the driver before
> >> sending.
> > Hmm. That's odd, I did check  using arm64 defconfig. My apologies.
> > Could you kindly share your build commands so that I can use this
> > going forward?
> >>
> >> s/cros_usbpd_acpi_device_ids/cros_usbpd_notify_acpi_device_ids/
> >>
>
> one problem is the above^
>
> drivers/platform/chrome/cros_usbpd_notify.c:67:27: error:
> ‘cros_usbpd_acpi_device_ids’ undeclared here (not in a function); did you mean
> ‘cros_usbpd_notify_acpi_device_ids’?
>
> The others I didn't dig in. My build commands are the common.
>
> make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- defconfig
> # Enable the new cros_usbpd_notify driver
> make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- -j4
This is helpful. Thanks Enric!
>
> Cheers,
>  Enric
>
> >> Apart from this I'm getting build errors with my defconfig which has CONFIG_ACPI
> >> and CONFIG_OF enabled.
> >>
> >> Another problem that I have with this driver is that actually there is no user
> >> for it. I'd really prefer have this included on a series that also introduces
> >> the user of this notifier. If you are only testing the ACPI case you can focus
> >> first on this use case and we add later the OF case (maybe is an easy way to
> >> proceed).
> > I'm testing with an arm64 device too locally. I will try to
> > incorporate the new change which updates cros_usbpd-charger to use the
> > notifier mechanism. I think we can try for the OF case simultaneously
> > (it is probably just the build errors I need to check for)
> >
> > Thanks again!
> >>
> >> Thanks,
> >>  Enric
> >>
> >>> +
> >>> +static struct acpi_driver cros_usbpd_notify_acpi_driver = {
> >>> +     .name = DRV_NAME,
> >>> +     .class = DRV_NAME,
> >>> +     .ids = cros_usbpd_notify_acpi_device_ids,
> >>> +     .ops = {
> >>> +             .add = cros_usbpd_notify_add_acpi,
> >>> +             .notify = cros_usbpd_notify_acpi,
> >>> +     },
> >>> +};
> >>> +module_acpi_driver(cros_usbpd_notify_acpi_driver);
> >>> +
> >>> +#endif /* CONFIG_ACPI */
> >>> +
> >>> +#ifdef CONFIG_OF
> >>> +
> >>> +static int cros_usbpd_notify_plat(struct notifier_block *nb,
> >>> +             unsigned long queued_during_suspend, void *data)
> >>> +{
> >>> +     struct cros_ec_device *ec_dev = (struct cros_ec_device *)data;
> >>> +     u32 host_event = cros_ec_get_host_event(ec_dev);
> >>> +
> >>> +     if (!host_event)
> >>> +             return NOTIFY_BAD;
> >>> +
> >>> +     if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU)) {
> >>> +             blocking_notifier_call_chain(&cros_usbpd_notifier_list,
> >>> +                             host_event, NULL);
> >>> +             return NOTIFY_OK;
> >>> +     }
> >>> +     return NOTIFY_DONE;
> >>> +}
> >>> +
> >>> +static int cros_usbpd_notify_probe_plat(struct platform_device *pdev)
> >>> +{
> >>> +     struct device *dev = &pdev->dev;
> >>> +     struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent);
> >>> +     struct notifier_block *nb;
> >>> +     int ret;
> >>> +
> >>> +     nb = devm_kzalloc(dev, sizeof(*nb), GFP_KERNEL);
> >>> +     if (!nb)
> >>> +             return -ENOMEM;
> >>> +
> >>> +     nb->notifier_call = cros_usbpd_notify_plat;
> >>> +     dev_set_drvdata(dev, nb);
> >>> +
> >>> +     ret = blocking_notifier_chain_register(&ecdev->ec_dev->event_notifier,
> >>> +                                             nb);
> >>> +     if (ret < 0) {
> >>> +             dev_err(dev, "Failed to register notifier\n");
> >>> +             return ret;
> >>> +     }
> >>> +
> >>> +     return 0;
> >>> +}
> >>> +
> >>> +static int cros_usbpd_notify_remove_plat(struct platform_device *pdev)
> >>> +{
> >>> +     struct device *dev = &pdev->dev;
> >>> +     struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent);
> >>> +     struct notifier_block *nb =
> >>> +             (struct notifier_block *)dev_get_drvdata(dev);
> >>> +
> >>> +     blocking_notifier_chain_unregister(&ecdev->ec_dev->event_notifier,
> >>> +                     nb);
> >>> +
> >>> +     return 0;
> >>> +}
> >>> +
> >>> +static struct platform_driver cros_usbpd_notify_plat_driver = {
> >>> +     .driver = {
> >>> +             .name = DRV_NAME,
> >>> +     },
> >>> +     .probe = cros_usbpd_notify_probe_plat,
> >>> +     .remove = cros_usbpd_notify_remove_plat,
> >>> +};
> >>> +module_platform_driver(cros_usbpd_notify_plat_driver);
> >>> +
> >>> +#endif /* CONFIG_OF */
> >>> +
> >>> +MODULE_LICENSE("GPL");
> >>> +MODULE_DESCRIPTION("ChromeOS power delivery notifier device");
> >>> +MODULE_AUTHOR("Jon Flatley <jflat@chromium.org>");
> >>> +MODULE_ALIAS("platform:" DRV_NAME);
> >>> diff --git a/include/linux/platform_data/cros_usbpd_notify.h b/include/linux/platform_data/cros_usbpd_notify.h
> >>> new file mode 100644
> >>> index 0000000000000..4f2791722b6d3
> >>> --- /dev/null
> >>> +++ b/include/linux/platform_data/cros_usbpd_notify.h
> >>> @@ -0,0 +1,17 @@
> >>> +// SPDX-License-Identifier: GPL-2.0-only
> >>> +/*
> >>> + * ChromeOS EC Power Delivery Notifier Driver
> >>> + *
> >>> + * Copyright 2020 Google LLC
> >>> + */
> >>> +
> >>> +#ifndef __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H
> >>> +#define __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H
> >>> +
> >>> +#include <linux/notifier.h>
> >>> +
> >>> +int cros_usbpd_register_notify(struct notifier_block *nb);
> >>> +
> >>> +void cros_usbpd_unregister_notify(struct notifier_block *nb);
> >>> +
> >>> +#endif  /* __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H */
> >>>

Re: [PATCH v5 2/2] mfd: cros_ec: Add cros-usbpd-notify subdevice

[Lee Jones]

On Mon, 13 Jan 2020, Prashant Malani wrote:

> Add the cros-usbpd-notify driver as a subdevice on platforms that
> support the EC_FEATURE_USB_PD EC feature flag and don't have the
> ACPI PD notification device defined.
> 
> This driver allows other cros-ec devices to receive PD event
> notifications from the Chrome OS Embedded Controller (EC) via a
> notification chain.
> 
> Signed-off-by: Prashant Malani <pmalani@chromium.org>
> ---
> 
> Changes in v5:
> - Updated the IS_ENABLED() check to check for CONFIG_OF instead of
>   !CONFIG_ACPI according to upstream comments.
> 
> Changes in v4:
> - Removed #ifndef usage; instead, moved cros-usbpd-notify to a separate
>   mfd_cell and used an IS_ENABLED() check.
> - Changed commit title and description slightly to reflect change in
>   code.
> 
>  drivers/mfd/cros_ec_dev.c | 22 ++++++++++++++++++++++
>  1 file changed, 22 insertions(+)

Looks okay to me, but I would like more Chromium reviews please.

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
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