diff mbox series

[v2,3/5] soc: add polarfire soc system controller

Message ID 20201201110257.28507-1-conor.dooley@microchip.com (mailing list archive)
State New, archived
Headers show
Series Add support for the PolarFire SoC system controller | expand

Commit Message

Conor Dooley Dec. 1, 2020, 11:02 a.m. UTC 
From: Conor Dooley <conor.dooley@microchip.com>

This driver provides an interface for other drivers to access the
functions of the system controller on the Microchip PolarFire SoC.

Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
 drivers/soc/Kconfig                         |   1 +
 drivers/soc/Makefile                        |   1 +
 drivers/soc/microchip/Kconfig               |  10 ++
 drivers/soc/microchip/Makefile              |   1 +
 drivers/soc/microchip/mpfs_sys_controller.c | 135 ++++++++++++++++++++
 5 files changed, 148 insertions(+)
 create mode 100644 drivers/soc/microchip/Kconfig
 create mode 100644 drivers/soc/microchip/Makefile
 create mode 100644 drivers/soc/microchip/mpfs_sys_controller.c

Comments

Damien Le Moal Dec. 1, 2020, noon UTC | #1 
On 2020/12/01 20:03, conor.dooley@microchip.com wrote:
> From: Conor Dooley <conor.dooley@microchip.com>
> 
> This driver provides an interface for other drivers to access the
> functions of the system controller on the Microchip PolarFire SoC.
> 
> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
> ---
>  drivers/soc/Kconfig                         |   1 +
>  drivers/soc/Makefile                        |   1 +
>  drivers/soc/microchip/Kconfig               |  10 ++
>  drivers/soc/microchip/Makefile              |   1 +
>  drivers/soc/microchip/mpfs_sys_controller.c | 135 ++++++++++++++++++++
>  5 files changed, 148 insertions(+)
>  create mode 100644 drivers/soc/microchip/Kconfig
>  create mode 100644 drivers/soc/microchip/Makefile
>  create mode 100644 drivers/soc/microchip/mpfs_sys_controller.c
> 
> diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
> index 425ab6f7e375..22cb097bcbdc 100644
> --- a/drivers/soc/Kconfig
> +++ b/drivers/soc/Kconfig
> @@ -9,6 +9,7 @@ source "drivers/soc/bcm/Kconfig"
>  source "drivers/soc/fsl/Kconfig"
>  source "drivers/soc/imx/Kconfig"
>  source "drivers/soc/ixp4xx/Kconfig"
> +source "drivers/soc/microchip/Kconfig"
>  source "drivers/soc/mediatek/Kconfig"
>  source "drivers/soc/qcom/Kconfig"
>  source "drivers/soc/renesas/Kconfig"
> diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
> index 36452bed86ef..fb084cf2d12e 100644
> --- a/drivers/soc/Makefile
> +++ b/drivers/soc/Makefile
> @@ -14,6 +14,7 @@ obj-$(CONFIG_ARCH_GEMINI)	+= gemini/
>  obj-y				+= imx/
>  obj-$(CONFIG_ARCH_IXP4XX)	+= ixp4xx/
>  obj-$(CONFIG_SOC_XWAY)		+= lantiq/
> +obj-$(CONFIG_SOC_MICROCHIP_POLARFIRE)	+= microchip/
>  obj-y				+= mediatek/
>  obj-y				+= amlogic/
>  obj-y				+= qcom/
> diff --git a/drivers/soc/microchip/Kconfig b/drivers/soc/microchip/Kconfig
> new file mode 100644
> index 000000000000..40e5203c8ba0
> --- /dev/null
> +++ b/drivers/soc/microchip/Kconfig
> @@ -0,0 +1,10 @@
> +config MPFS_SYS_CONTROLLER
> +	tristate "MPFS_SYS_CONTROLLER"
> +	depends on MPFS_MBOX
> +	help
> +	  This driver adds support for the Polarfire SoC system controller.
> +
> +	  To compile this driver as a module, choose M here. the
> +	  module will be called mpfs_system_controller.
> +
> +	  If unsure, say N.
> diff --git a/drivers/soc/microchip/Makefile b/drivers/soc/microchip/Makefile
> new file mode 100644
> index 000000000000..23b1f42a37db
> --- /dev/null
> +++ b/drivers/soc/microchip/Makefile
> @@ -0,0 +1 @@
> +obj-$(CONFIG_MPFS_SYS_CONTROLLER)	+= mpfs_sys_controller.o
> diff --git a/drivers/soc/microchip/mpfs_sys_controller.c b/drivers/soc/microchip/mpfs_sys_controller.c
> new file mode 100644
> index 000000000000..875a0671e196
> --- /dev/null
> +++ b/drivers/soc/microchip/mpfs_sys_controller.c
> @@ -0,0 +1,135 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Microchip MPFS system controller driver
> + *
> + * Copyright (c) 2020 Microchip Corporation. All rights reserved.
> + *
> + * Author: Conor Dooley <conor.dooley@microchip.com>
> + *
> + */
> +
> +#include <linux/slab.h>
> +#include <linux/module.h>
> +#include <linux/interrupt.h>
> +#include <linux/of_platform.h>
> +#include <linux/mailbox_client.h>
> +#include <linux/platform_device.h>
> +#include <soc/microchip/mpfs.h>
> +
> +static DEFINE_MUTEX(transaction_lock);
> +
> +struct mpfs_sys_controller {
> +	struct mbox_client client;
> +	struct mbox_chan *chan;
> +	struct completion c;
> +	u32 enabled;
> +	void *response;
> +	u16 response_size_bytes;
> +};
> +
> +int mpfs_blocking_transaction(struct mpfs_sys_controller *mpfs_client, void *msg,
> +			      void *response, u16 response_size_bytes)
> +{
> +	int ret;
> +
> +	mpfs_client->response = response;
> +	mpfs_client->response_size_bytes = response_size_bytes;
> +
> +	mutex_lock_interruptible(&transaction_lock);
> +
> +	reinit_completion(&mpfs_client->c);
> +
> +	ret = mbox_send_message(mpfs_client->chan, msg);
> +	if (ret >= 0) {
> +		if (wait_for_completion_timeout(&mpfs_client->c, HZ)) {
> +			ret = 0;
> +		} else {
> +			ret = -ETIMEDOUT;
> +			dev_warn(mpfs_client->client.dev, "MPFS sys controller transaction timeout");
> +		}
> +	} else {
> +		dev_err(mpfs_client->client.dev,
> +			"mpfs sys controller transaction returned %d\r\n", ret);
> +	}
> +
> +	mutex_unlock(&transaction_lock);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL(mpfs_blocking_transaction);
> +
> +static void rx_callback(struct mbox_client *client, void *msg)
> +{
> +	struct mpfs_sys_controller *mpfs_client =
> +		container_of(client, struct mpfs_sys_controller, client);
> +
> +	memcpy(mpfs_client->response, (u8 *)msg,
> +	       mpfs_client->response_size_bytes);
> +
> +	complete(&mpfs_client->c);
> +}
> +
> +static int mpfs_sys_controller_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct mpfs_sys_controller *mpfs_client;
> +
> +	mpfs_client = devm_kzalloc(dev, sizeof(*mpfs_client), GFP_KERNEL);
> +	if (!mpfs_client)
> +		return -ENOMEM;
> +
> +	mpfs_client->client.dev = dev;
> +	mpfs_client->client.rx_callback = rx_callback;
> +	mpfs_client->client.tx_block = 1U;
> +
> +	mpfs_client->chan = mbox_request_channel_byname(&mpfs_client->client,
> +							"mbox-mpfs");
> +	if (IS_ERR(mpfs_client->chan)) {
> +		int ret = PTR_ERR(mpfs_client->chan);
> +
> +		if (ret != -EPROBE_DEFER)
> +			dev_err(dev, "Failed to get mbox channel: %d\n", ret);
> +		return ret;

You can replace all of this with

		return dev_err_probe(dev, PTR_ERR(mpfs_client->chan),
				     ""Failed to get mbox channel\n");

> +	}
> +
> +	init_completion(&mpfs_client->c);
> +
> +	platform_set_drvdata(pdev, mpfs_client);
> +
> +	dev_info(&pdev->dev, "Registered MPFS system controller driver\n");
> +
> +	return 0;
> +}
> +
> +struct mpfs_sys_controller *
> +mpfs_sys_controller_get(struct device_node *mss_node)
> +{
> +	struct platform_device *pdev = of_find_device_by_node(mss_node);
> +
> +	if (!pdev)
> +		return NULL;
> +
> +	return platform_get_drvdata(pdev);
> +}
> +EXPORT_SYMBOL(mpfs_sys_controller_get);
> +
> +static const struct of_device_id mpfs_sys_controller_of_match[] = {
> +	{
> +		.compatible = "microchip,polarfire-soc-sys-controller",
> +	},
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, mpfs_sys_controller_of_match);
> +
> +static struct platform_driver mpfs_sys_controller_driver = {
> +	.driver = {
> +		.name = "mpfs-sys-controller",
> +		.of_match_table = mpfs_sys_controller_of_match,
> +	},
> +	.probe = mpfs_sys_controller_probe,
> +};
> +module_platform_driver(mpfs_sys_controller_driver);
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
> +MODULE_DESCRIPTION("MPFS system controller driver");
>
Ben Dooks Dec. 1, 2020, 12:18 p.m. UTC | #2 
On 01/12/2020 12:00, Damien Le Moal wrote:
> On 2020/12/01 20:03, conor.dooley@microchip.com wrote:
>> From: Conor Dooley <conor.dooley@microchip.com>
>>
>> This driver provides an interface for other drivers to access the
>> functions of the system controller on the Microchip PolarFire SoC.
>>
>> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
>> ---
>>   drivers/soc/Kconfig                         |   1 +
>>   drivers/soc/Makefile                        |   1 +
>>   drivers/soc/microchip/Kconfig               |  10 ++
>>   drivers/soc/microchip/Makefile              |   1 +
>>   drivers/soc/microchip/mpfs_sys_controller.c | 135 ++++++++++++++++++++
>>   5 files changed, 148 insertions(+)
>>   create mode 100644 drivers/soc/microchip/Kconfig
>>   create mode 100644 drivers/soc/microchip/Makefile
>>   create mode 100644 drivers/soc/microchip/mpfs_sys_controller.c
>>
>> diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
>> index 425ab6f7e375..22cb097bcbdc 100644
>> --- a/drivers/soc/Kconfig
>> +++ b/drivers/soc/Kconfig
>> @@ -9,6 +9,7 @@ source "drivers/soc/bcm/Kconfig"
>>   source "drivers/soc/fsl/Kconfig"
>>   source "drivers/soc/imx/Kconfig"
>>   source "drivers/soc/ixp4xx/Kconfig"
>> +source "drivers/soc/microchip/Kconfig"
>>   source "drivers/soc/mediatek/Kconfig"
>>   source "drivers/soc/qcom/Kconfig"
>>   source "drivers/soc/renesas/Kconfig"
>> diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
>> index 36452bed86ef..fb084cf2d12e 100644
>> --- a/drivers/soc/Makefile
>> +++ b/drivers/soc/Makefile
>> @@ -14,6 +14,7 @@ obj-$(CONFIG_ARCH_GEMINI)	+= gemini/
>>   obj-y				+= imx/
>>   obj-$(CONFIG_ARCH_IXP4XX)	+= ixp4xx/
>>   obj-$(CONFIG_SOC_XWAY)		+= lantiq/
>> +obj-$(CONFIG_SOC_MICROCHIP_POLARFIRE)	+= microchip/
>>   obj-y				+= mediatek/
>>   obj-y				+= amlogic/
>>   obj-y				+= qcom/
>> diff --git a/drivers/soc/microchip/Kconfig b/drivers/soc/microchip/Kconfig
>> new file mode 100644
>> index 000000000000..40e5203c8ba0
>> --- /dev/null
>> +++ b/drivers/soc/microchip/Kconfig
>> @@ -0,0 +1,10 @@
>> +config MPFS_SYS_CONTROLLER
>> +	tristate "MPFS_SYS_CONTROLLER"
>> +	depends on MPFS_MBOX
>> +	help
>> +	  This driver adds support for the Polarfire SoC system controller.
>> +
>> +	  To compile this driver as a module, choose M here. the
>> +	  module will be called mpfs_system_controller.
>> +
>> +	  If unsure, say N.
>> diff --git a/drivers/soc/microchip/Makefile b/drivers/soc/microchip/Makefile
>> new file mode 100644
>> index 000000000000..23b1f42a37db
>> --- /dev/null
>> +++ b/drivers/soc/microchip/Makefile
>> @@ -0,0 +1 @@
>> +obj-$(CONFIG_MPFS_SYS_CONTROLLER)	+= mpfs_sys_controller.o
>> diff --git a/drivers/soc/microchip/mpfs_sys_controller.c b/drivers/soc/microchip/mpfs_sys_controller.c
>> new file mode 100644
>> index 000000000000..875a0671e196
>> --- /dev/null
>> +++ b/drivers/soc/microchip/mpfs_sys_controller.c
>> @@ -0,0 +1,135 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Microchip MPFS system controller driver
>> + *
>> + * Copyright (c) 2020 Microchip Corporation. All rights reserved.
>> + *
>> + * Author: Conor Dooley <conor.dooley@microchip.com>
>> + *
>> + */
>> +
>> +#include <linux/slab.h>
>> +#include <linux/module.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/of_platform.h>
>> +#include <linux/mailbox_client.h>
>> +#include <linux/platform_device.h>
>> +#include <soc/microchip/mpfs.h>
>> +
>> +static DEFINE_MUTEX(transaction_lock);
>> +
>> +struct mpfs_sys_controller {
>> +	struct mbox_client client;
>> +	struct mbox_chan *chan;
>> +	struct completion c;
>> +	u32 enabled;
>> +	void *response;
>> +	u16 response_size_bytes;
>> +};
>> +
>> +int mpfs_blocking_transaction(struct mpfs_sys_controller *mpfs_client, void *msg,
>> +			      void *response, u16 response_size_bytes)
>> +{
>> +	int ret;
>> +
>> +	mpfs_client->response = response;
>> +	mpfs_client->response_size_bytes = response_size_bytes;
>> +
>> +	mutex_lock_interruptible(&transaction_lock);
>> +
>> +	reinit_completion(&mpfs_client->c);
>> +
>> +	ret = mbox_send_message(mpfs_client->chan, msg);
>> +	if (ret >= 0) {
>> +		if (wait_for_completion_timeout(&mpfs_client->c, HZ)) {
>> +			ret = 0;
>> +		} else {
>> +			ret = -ETIMEDOUT;
>> +			dev_warn(mpfs_client->client.dev, "MPFS sys controller transaction timeout");
>> +		}
>> +	} else {
>> +		dev_err(mpfs_client->client.dev,
>> +			"mpfs sys controller transaction returned %d\r\n", ret);
>> +	}
>> +
>> +	mutex_unlock(&transaction_lock);
>> +
>> +	return ret;
>> +}
>> +EXPORT_SYMBOL(mpfs_blocking_transaction);
>> +
>> +static void rx_callback(struct mbox_client *client, void *msg)
>> +{
>> +	struct mpfs_sys_controller *mpfs_client =
>> +		container_of(client, struct mpfs_sys_controller, client);
>> +
>> +	memcpy(mpfs_client->response, (u8 *)msg,
>> +	       mpfs_client->response_size_bytes);
>> +
>> +	complete(&mpfs_client->c);
>> +}
>> +
>> +static int mpfs_sys_controller_probe(struct platform_device *pdev)
>> +{
>> +	struct device *dev = &pdev->dev;
>> +	struct mpfs_sys_controller *mpfs_client;
>> +
>> +	mpfs_client = devm_kzalloc(dev, sizeof(*mpfs_client), GFP_KERNEL);
>> +	if (!mpfs_client)
>> +		return -ENOMEM;
>> +
>> +	mpfs_client->client.dev = dev;
>> +	mpfs_client->client.rx_callback = rx_callback;
>> +	mpfs_client->client.tx_block = 1U;
>> +
>> +	mpfs_client->chan = mbox_request_channel_byname(&mpfs_client->client,
>> +							"mbox-mpfs");
>> +	if (IS_ERR(mpfs_client->chan)) {
>> +		int ret = PTR_ERR(mpfs_client->chan);
>> +
>> +		if (ret != -EPROBE_DEFER)
>> +			dev_err(dev, "Failed to get mbox channel: %d\n", ret);
>> +		return ret;
> 
> You can replace all of this with
> 
> 		return dev_err_probe(dev, PTR_ERR(mpfs_client->chan),
> 				     ""Failed to get mbox channel\n");

you'll spam the error log if you get a lot of probe defferals.
I think the code as is fine.
Damien Le Moal Dec. 1, 2020, 12:21 p.m. UTC | #3 
On 2020/12/01 21:18, Ben Dooks wrote:
> On 01/12/2020 12:00, Damien Le Moal wrote:
>> On 2020/12/01 20:03, conor.dooley@microchip.com wrote:
>>> From: Conor Dooley <conor.dooley@microchip.com>
>>>
>>> This driver provides an interface for other drivers to access the
>>> functions of the system controller on the Microchip PolarFire SoC.
>>>
>>> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
>>> ---
>>>   drivers/soc/Kconfig                         |   1 +
>>>   drivers/soc/Makefile                        |   1 +
>>>   drivers/soc/microchip/Kconfig               |  10 ++
>>>   drivers/soc/microchip/Makefile              |   1 +
>>>   drivers/soc/microchip/mpfs_sys_controller.c | 135 ++++++++++++++++++++
>>>   5 files changed, 148 insertions(+)
>>>   create mode 100644 drivers/soc/microchip/Kconfig
>>>   create mode 100644 drivers/soc/microchip/Makefile
>>>   create mode 100644 drivers/soc/microchip/mpfs_sys_controller.c
>>>
>>> diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
>>> index 425ab6f7e375..22cb097bcbdc 100644
>>> --- a/drivers/soc/Kconfig
>>> +++ b/drivers/soc/Kconfig
>>> @@ -9,6 +9,7 @@ source "drivers/soc/bcm/Kconfig"
>>>   source "drivers/soc/fsl/Kconfig"
>>>   source "drivers/soc/imx/Kconfig"
>>>   source "drivers/soc/ixp4xx/Kconfig"
>>> +source "drivers/soc/microchip/Kconfig"
>>>   source "drivers/soc/mediatek/Kconfig"
>>>   source "drivers/soc/qcom/Kconfig"
>>>   source "drivers/soc/renesas/Kconfig"
>>> diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
>>> index 36452bed86ef..fb084cf2d12e 100644
>>> --- a/drivers/soc/Makefile
>>> +++ b/drivers/soc/Makefile
>>> @@ -14,6 +14,7 @@ obj-$(CONFIG_ARCH_GEMINI)	+= gemini/
>>>   obj-y				+= imx/
>>>   obj-$(CONFIG_ARCH_IXP4XX)	+= ixp4xx/
>>>   obj-$(CONFIG_SOC_XWAY)		+= lantiq/
>>> +obj-$(CONFIG_SOC_MICROCHIP_POLARFIRE)	+= microchip/
>>>   obj-y				+= mediatek/
>>>   obj-y				+= amlogic/
>>>   obj-y				+= qcom/
>>> diff --git a/drivers/soc/microchip/Kconfig b/drivers/soc/microchip/Kconfig
>>> new file mode 100644
>>> index 000000000000..40e5203c8ba0
>>> --- /dev/null
>>> +++ b/drivers/soc/microchip/Kconfig
>>> @@ -0,0 +1,10 @@
>>> +config MPFS_SYS_CONTROLLER
>>> +	tristate "MPFS_SYS_CONTROLLER"
>>> +	depends on MPFS_MBOX
>>> +	help
>>> +	  This driver adds support for the Polarfire SoC system controller.
>>> +
>>> +	  To compile this driver as a module, choose M here. the
>>> +	  module will be called mpfs_system_controller.
>>> +
>>> +	  If unsure, say N.
>>> diff --git a/drivers/soc/microchip/Makefile b/drivers/soc/microchip/Makefile
>>> new file mode 100644
>>> index 000000000000..23b1f42a37db
>>> --- /dev/null
>>> +++ b/drivers/soc/microchip/Makefile
>>> @@ -0,0 +1 @@
>>> +obj-$(CONFIG_MPFS_SYS_CONTROLLER)	+= mpfs_sys_controller.o
>>> diff --git a/drivers/soc/microchip/mpfs_sys_controller.c b/drivers/soc/microchip/mpfs_sys_controller.c
>>> new file mode 100644
>>> index 000000000000..875a0671e196
>>> --- /dev/null
>>> +++ b/drivers/soc/microchip/mpfs_sys_controller.c
>>> @@ -0,0 +1,135 @@
>>> +// SPDX-License-Identifier: GPL-2.0
>>> +/*
>>> + * Microchip MPFS system controller driver
>>> + *
>>> + * Copyright (c) 2020 Microchip Corporation. All rights reserved.
>>> + *
>>> + * Author: Conor Dooley <conor.dooley@microchip.com>
>>> + *
>>> + */
>>> +
>>> +#include <linux/slab.h>
>>> +#include <linux/module.h>
>>> +#include <linux/interrupt.h>
>>> +#include <linux/of_platform.h>
>>> +#include <linux/mailbox_client.h>
>>> +#include <linux/platform_device.h>
>>> +#include <soc/microchip/mpfs.h>
>>> +
>>> +static DEFINE_MUTEX(transaction_lock);
>>> +
>>> +struct mpfs_sys_controller {
>>> +	struct mbox_client client;
>>> +	struct mbox_chan *chan;
>>> +	struct completion c;
>>> +	u32 enabled;
>>> +	void *response;
>>> +	u16 response_size_bytes;
>>> +};
>>> +
>>> +int mpfs_blocking_transaction(struct mpfs_sys_controller *mpfs_client, void *msg,
>>> +			      void *response, u16 response_size_bytes)
>>> +{
>>> +	int ret;
>>> +
>>> +	mpfs_client->response = response;
>>> +	mpfs_client->response_size_bytes = response_size_bytes;
>>> +
>>> +	mutex_lock_interruptible(&transaction_lock);
>>> +
>>> +	reinit_completion(&mpfs_client->c);
>>> +
>>> +	ret = mbox_send_message(mpfs_client->chan, msg);
>>> +	if (ret >= 0) {
>>> +		if (wait_for_completion_timeout(&mpfs_client->c, HZ)) {
>>> +			ret = 0;
>>> +		} else {
>>> +			ret = -ETIMEDOUT;
>>> +			dev_warn(mpfs_client->client.dev, "MPFS sys controller transaction timeout");
>>> +		}
>>> +	} else {
>>> +		dev_err(mpfs_client->client.dev,
>>> +			"mpfs sys controller transaction returned %d\r\n", ret);
>>> +	}
>>> +
>>> +	mutex_unlock(&transaction_lock);
>>> +
>>> +	return ret;
>>> +}
>>> +EXPORT_SYMBOL(mpfs_blocking_transaction);
>>> +
>>> +static void rx_callback(struct mbox_client *client, void *msg)
>>> +{
>>> +	struct mpfs_sys_controller *mpfs_client =
>>> +		container_of(client, struct mpfs_sys_controller, client);
>>> +
>>> +	memcpy(mpfs_client->response, (u8 *)msg,
>>> +	       mpfs_client->response_size_bytes);
>>> +
>>> +	complete(&mpfs_client->c);
>>> +}
>>> +
>>> +static int mpfs_sys_controller_probe(struct platform_device *pdev)
>>> +{
>>> +	struct device *dev = &pdev->dev;
>>> +	struct mpfs_sys_controller *mpfs_client;
>>> +
>>> +	mpfs_client = devm_kzalloc(dev, sizeof(*mpfs_client), GFP_KERNEL);
>>> +	if (!mpfs_client)
>>> +		return -ENOMEM;
>>> +
>>> +	mpfs_client->client.dev = dev;
>>> +	mpfs_client->client.rx_callback = rx_callback;
>>> +	mpfs_client->client.tx_block = 1U;
>>> +
>>> +	mpfs_client->chan = mbox_request_channel_byname(&mpfs_client->client,
>>> +							"mbox-mpfs");
>>> +	if (IS_ERR(mpfs_client->chan)) {
>>> +		int ret = PTR_ERR(mpfs_client->chan);
>>> +
>>> +		if (ret != -EPROBE_DEFER)
>>> +			dev_err(dev, "Failed to get mbox channel: %d\n", ret);
>>> +		return ret;
>>
>> You can replace all of this with
>>
>> 		return dev_err_probe(dev, PTR_ERR(mpfs_client->chan),
>> 				     ""Failed to get mbox channel\n");
> 
> you'll spam the error log if you get a lot of probe defferals.
> I think the code as is fine.

Please look at that function code: it does not print anything if the error is
-EPROBE_DEFER.
Ben Dooks Dec. 1, 2020, 12:29 p.m. UTC | #4 
On 01/12/2020 12:21, Damien Le Moal wrote:
> On 2020/12/01 21:18, Ben Dooks wrote:
>> On 01/12/2020 12:00, Damien Le Moal wrote:
>>> On 2020/12/01 20:03, conor.dooley@microchip.com wrote:
>>>> From: Conor Dooley <conor.dooley@microchip.com>
>>>>
>>>> This driver provides an interface for other drivers to access the
>>>> functions of the system controller on the Microchip PolarFire SoC.
>>>>
>>>> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
>>>> ---
>>>>    drivers/soc/Kconfig                         |   1 +
>>>>    drivers/soc/Makefile                        |   1 +
>>>>    drivers/soc/microchip/Kconfig               |  10 ++
>>>>    drivers/soc/microchip/Makefile              |   1 +
>>>>    drivers/soc/microchip/mpfs_sys_controller.c | 135 ++++++++++++++++++++
>>>>    5 files changed, 148 insertions(+)
>>>>    create mode 100644 drivers/soc/microchip/Kconfig
>>>>    create mode 100644 drivers/soc/microchip/Makefile
>>>>    create mode 100644 drivers/soc/microchip/mpfs_sys_controller.c
>>>>
>>>> diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
>>>> index 425ab6f7e375..22cb097bcbdc 100644
>>>> --- a/drivers/soc/Kconfig
>>>> +++ b/drivers/soc/Kconfig
>>>> @@ -9,6 +9,7 @@ source "drivers/soc/bcm/Kconfig"
>>>>    source "drivers/soc/fsl/Kconfig"
>>>>    source "drivers/soc/imx/Kconfig"
>>>>    source "drivers/soc/ixp4xx/Kconfig"
>>>> +source "drivers/soc/microchip/Kconfig"
>>>>    source "drivers/soc/mediatek/Kconfig"
>>>>    source "drivers/soc/qcom/Kconfig"
>>>>    source "drivers/soc/renesas/Kconfig"
>>>> diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
>>>> index 36452bed86ef..fb084cf2d12e 100644
>>>> --- a/drivers/soc/Makefile
>>>> +++ b/drivers/soc/Makefile
>>>> @@ -14,6 +14,7 @@ obj-$(CONFIG_ARCH_GEMINI)	+= gemini/
>>>>    obj-y				+= imx/
>>>>    obj-$(CONFIG_ARCH_IXP4XX)	+= ixp4xx/
>>>>    obj-$(CONFIG_SOC_XWAY)		+= lantiq/
>>>> +obj-$(CONFIG_SOC_MICROCHIP_POLARFIRE)	+= microchip/
>>>>    obj-y				+= mediatek/
>>>>    obj-y				+= amlogic/
>>>>    obj-y				+= qcom/
>>>> diff --git a/drivers/soc/microchip/Kconfig b/drivers/soc/microchip/Kconfig
>>>> new file mode 100644
>>>> index 000000000000..40e5203c8ba0
>>>> --- /dev/null
>>>> +++ b/drivers/soc/microchip/Kconfig
>>>> @@ -0,0 +1,10 @@
>>>> +config MPFS_SYS_CONTROLLER
>>>> +	tristate "MPFS_SYS_CONTROLLER"
>>>> +	depends on MPFS_MBOX
>>>> +	help
>>>> +	  This driver adds support for the Polarfire SoC system controller.
>>>> +
>>>> +	  To compile this driver as a module, choose M here. the
>>>> +	  module will be called mpfs_system_controller.
>>>> +
>>>> +	  If unsure, say N.
>>>> diff --git a/drivers/soc/microchip/Makefile b/drivers/soc/microchip/Makefile
>>>> new file mode 100644
>>>> index 000000000000..23b1f42a37db
>>>> --- /dev/null
>>>> +++ b/drivers/soc/microchip/Makefile
>>>> @@ -0,0 +1 @@
>>>> +obj-$(CONFIG_MPFS_SYS_CONTROLLER)	+= mpfs_sys_controller.o
>>>> diff --git a/drivers/soc/microchip/mpfs_sys_controller.c b/drivers/soc/microchip/mpfs_sys_controller.c
>>>> new file mode 100644
>>>> index 000000000000..875a0671e196
>>>> --- /dev/null
>>>> +++ b/drivers/soc/microchip/mpfs_sys_controller.c
>>>> @@ -0,0 +1,135 @@
>>>> +// SPDX-License-Identifier: GPL-2.0
>>>> +/*
>>>> + * Microchip MPFS system controller driver
>>>> + *
>>>> + * Copyright (c) 2020 Microchip Corporation. All rights reserved.
>>>> + *
>>>> + * Author: Conor Dooley <conor.dooley@microchip.com>
>>>> + *
>>>> + */
>>>> +
>>>> +#include <linux/slab.h>
>>>> +#include <linux/module.h>
>>>> +#include <linux/interrupt.h>
>>>> +#include <linux/of_platform.h>
>>>> +#include <linux/mailbox_client.h>
>>>> +#include <linux/platform_device.h>
>>>> +#include <soc/microchip/mpfs.h>
>>>> +
>>>> +static DEFINE_MUTEX(transaction_lock);
>>>> +
>>>> +struct mpfs_sys_controller {
>>>> +	struct mbox_client client;
>>>> +	struct mbox_chan *chan;
>>>> +	struct completion c;
>>>> +	u32 enabled;
>>>> +	void *response;
>>>> +	u16 response_size_bytes;
>>>> +};
>>>> +
>>>> +int mpfs_blocking_transaction(struct mpfs_sys_controller *mpfs_client, void *msg,
>>>> +			      void *response, u16 response_size_bytes)
>>>> +{
>>>> +	int ret;
>>>> +
>>>> +	mpfs_client->response = response;
>>>> +	mpfs_client->response_size_bytes = response_size_bytes;
>>>> +
>>>> +	mutex_lock_interruptible(&transaction_lock);
>>>> +
>>>> +	reinit_completion(&mpfs_client->c);
>>>> +
>>>> +	ret = mbox_send_message(mpfs_client->chan, msg);
>>>> +	if (ret >= 0) {
>>>> +		if (wait_for_completion_timeout(&mpfs_client->c, HZ)) {
>>>> +			ret = 0;
>>>> +		} else {
>>>> +			ret = -ETIMEDOUT;
>>>> +			dev_warn(mpfs_client->client.dev, "MPFS sys controller transaction timeout");
>>>> +		}
>>>> +	} else {
>>>> +		dev_err(mpfs_client->client.dev,
>>>> +			"mpfs sys controller transaction returned %d\r\n", ret);
>>>> +	}
>>>> +
>>>> +	mutex_unlock(&transaction_lock);
>>>> +
>>>> +	return ret;
>>>> +}
>>>> +EXPORT_SYMBOL(mpfs_blocking_transaction);
>>>> +
>>>> +static void rx_callback(struct mbox_client *client, void *msg)
>>>> +{
>>>> +	struct mpfs_sys_controller *mpfs_client =
>>>> +		container_of(client, struct mpfs_sys_controller, client);
>>>> +
>>>> +	memcpy(mpfs_client->response, (u8 *)msg,
>>>> +	       mpfs_client->response_size_bytes);
>>>> +
>>>> +	complete(&mpfs_client->c);
>>>> +}
>>>> +
>>>> +static int mpfs_sys_controller_probe(struct platform_device *pdev)
>>>> +{
>>>> +	struct device *dev = &pdev->dev;
>>>> +	struct mpfs_sys_controller *mpfs_client;
>>>> +
>>>> +	mpfs_client = devm_kzalloc(dev, sizeof(*mpfs_client), GFP_KERNEL);
>>>> +	if (!mpfs_client)
>>>> +		return -ENOMEM;
>>>> +
>>>> +	mpfs_client->client.dev = dev;
>>>> +	mpfs_client->client.rx_callback = rx_callback;
>>>> +	mpfs_client->client.tx_block = 1U;
>>>> +
>>>> +	mpfs_client->chan = mbox_request_channel_byname(&mpfs_client->client,
>>>> +							"mbox-mpfs");
>>>> +	if (IS_ERR(mpfs_client->chan)) {
>>>> +		int ret = PTR_ERR(mpfs_client->chan);
>>>> +
>>>> +		if (ret != -EPROBE_DEFER)
>>>> +			dev_err(dev, "Failed to get mbox channel: %d\n", ret);
>>>> +		return ret;
>>>
>>> You can replace all of this with
>>>
>>> 		return dev_err_probe(dev, PTR_ERR(mpfs_client->chan),
>>> 				     ""Failed to get mbox channel\n");
>>
>> you'll spam the error log if you get a lot of probe defferals.
>> I think the code as is fine.
> 
> Please look at that function code: it does not print anything if the error is
> -EPROBE_DEFER.
> 

ah, ok.
diff mbox series

Patch

diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index 425ab6f7e375..22cb097bcbdc 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -9,6 +9,7 @@  source "drivers/soc/bcm/Kconfig"
 source "drivers/soc/fsl/Kconfig"
 source "drivers/soc/imx/Kconfig"
 source "drivers/soc/ixp4xx/Kconfig"
+source "drivers/soc/microchip/Kconfig"
 source "drivers/soc/mediatek/Kconfig"
 source "drivers/soc/qcom/Kconfig"
 source "drivers/soc/renesas/Kconfig"
diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
index 36452bed86ef..fb084cf2d12e 100644
--- a/drivers/soc/Makefile
+++ b/drivers/soc/Makefile
@@ -14,6 +14,7 @@  obj-$(CONFIG_ARCH_GEMINI)	+= gemini/
 obj-y				+= imx/
 obj-$(CONFIG_ARCH_IXP4XX)	+= ixp4xx/
 obj-$(CONFIG_SOC_XWAY)		+= lantiq/
+obj-$(CONFIG_SOC_MICROCHIP_POLARFIRE)	+= microchip/
 obj-y				+= mediatek/
 obj-y				+= amlogic/
 obj-y				+= qcom/
diff --git a/drivers/soc/microchip/Kconfig b/drivers/soc/microchip/Kconfig
new file mode 100644
index 000000000000..40e5203c8ba0
--- /dev/null
+++ b/drivers/soc/microchip/Kconfig
@@ -0,0 +1,10 @@ 
+config MPFS_SYS_CONTROLLER
+	tristate "MPFS_SYS_CONTROLLER"
+	depends on MPFS_MBOX
+	help
+	  This driver adds support for the Polarfire SoC system controller.
+
+	  To compile this driver as a module, choose M here. the
+	  module will be called mpfs_system_controller.
+
+	  If unsure, say N.
diff --git a/drivers/soc/microchip/Makefile b/drivers/soc/microchip/Makefile
new file mode 100644
index 000000000000..23b1f42a37db
--- /dev/null
+++ b/drivers/soc/microchip/Makefile
@@ -0,0 +1 @@ 
+obj-$(CONFIG_MPFS_SYS_CONTROLLER)	+= mpfs_sys_controller.o
diff --git a/drivers/soc/microchip/mpfs_sys_controller.c b/drivers/soc/microchip/mpfs_sys_controller.c
new file mode 100644
index 000000000000..875a0671e196
--- /dev/null
+++ b/drivers/soc/microchip/mpfs_sys_controller.c
@@ -0,0 +1,135 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Microchip MPFS system controller driver
+ *
+ * Copyright (c) 2020 Microchip Corporation. All rights reserved.
+ *
+ * Author: Conor Dooley <conor.dooley@microchip.com>
+ *
+ */
+
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/of_platform.h>
+#include <linux/mailbox_client.h>
+#include <linux/platform_device.h>
+#include <soc/microchip/mpfs.h>
+
+static DEFINE_MUTEX(transaction_lock);
+
+struct mpfs_sys_controller {
+	struct mbox_client client;
+	struct mbox_chan *chan;
+	struct completion c;
+	u32 enabled;
+	void *response;
+	u16 response_size_bytes;
+};
+
+int mpfs_blocking_transaction(struct mpfs_sys_controller *mpfs_client, void *msg,
+			      void *response, u16 response_size_bytes)
+{
+	int ret;
+
+	mpfs_client->response = response;
+	mpfs_client->response_size_bytes = response_size_bytes;
+
+	mutex_lock_interruptible(&transaction_lock);
+
+	reinit_completion(&mpfs_client->c);
+
+	ret = mbox_send_message(mpfs_client->chan, msg);
+	if (ret >= 0) {
+		if (wait_for_completion_timeout(&mpfs_client->c, HZ)) {
+			ret = 0;
+		} else {
+			ret = -ETIMEDOUT;
+			dev_warn(mpfs_client->client.dev, "MPFS sys controller transaction timeout");
+		}
+	} else {
+		dev_err(mpfs_client->client.dev,
+			"mpfs sys controller transaction returned %d\r\n", ret);
+	}
+
+	mutex_unlock(&transaction_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL(mpfs_blocking_transaction);
+
+static void rx_callback(struct mbox_client *client, void *msg)
+{
+	struct mpfs_sys_controller *mpfs_client =
+		container_of(client, struct mpfs_sys_controller, client);
+
+	memcpy(mpfs_client->response, (u8 *)msg,
+	       mpfs_client->response_size_bytes);
+
+	complete(&mpfs_client->c);
+}
+
+static int mpfs_sys_controller_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mpfs_sys_controller *mpfs_client;
+
+	mpfs_client = devm_kzalloc(dev, sizeof(*mpfs_client), GFP_KERNEL);
+	if (!mpfs_client)
+		return -ENOMEM;
+
+	mpfs_client->client.dev = dev;
+	mpfs_client->client.rx_callback = rx_callback;
+	mpfs_client->client.tx_block = 1U;
+
+	mpfs_client->chan = mbox_request_channel_byname(&mpfs_client->client,
+							"mbox-mpfs");
+	if (IS_ERR(mpfs_client->chan)) {
+		int ret = PTR_ERR(mpfs_client->chan);
+
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "Failed to get mbox channel: %d\n", ret);
+		return ret;
+	}
+
+	init_completion(&mpfs_client->c);
+
+	platform_set_drvdata(pdev, mpfs_client);
+
+	dev_info(&pdev->dev, "Registered MPFS system controller driver\n");
+
+	return 0;
+}
+
+struct mpfs_sys_controller *
+mpfs_sys_controller_get(struct device_node *mss_node)
+{
+	struct platform_device *pdev = of_find_device_by_node(mss_node);
+
+	if (!pdev)
+		return NULL;
+
+	return platform_get_drvdata(pdev);
+}
+EXPORT_SYMBOL(mpfs_sys_controller_get);
+
+static const struct of_device_id mpfs_sys_controller_of_match[] = {
+	{
+		.compatible = "microchip,polarfire-soc-sys-controller",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, mpfs_sys_controller_of_match);
+
+static struct platform_driver mpfs_sys_controller_driver = {
+	.driver = {
+		.name = "mpfs-sys-controller",
+		.of_match_table = mpfs_sys_controller_of_match,
+	},
+	.probe = mpfs_sys_controller_probe,
+};
+module_platform_driver(mpfs_sys_controller_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
+MODULE_DESCRIPTION("MPFS system controller driver");