Re: [PATCH 1/2] mfd: act8945a: add Active-semi ACT8945A PMIC MFD driver

From: Lee Jones
Date: Mon Jan 11 2016 - 00:49:29 EST


On Fri, 08 Jan 2016, Wenyou Yang wrote:

> This patch adds support for the Active-semi ACT8945A PMIC.
> It is a Multi Function Device with the following subdevices:
> - Regulator
> - Charger
>
> It is interfaced to the host controller using I2C interface,
> ACT8945A is a child device of the I2C.
>
> Signed-off-by: Wenyou Yang <wenyou.yang@xxxxxxxxx>
> ---
>
> drivers/mfd/Kconfig | 8 +++
> drivers/mfd/Makefile | 1 +
> drivers/mfd/act8945a.c | 122 ++++++++++++++++++++++++++++++++++++++++++
> include/linux/mfd/act8945a.h | 25 +++++++++
> 4 files changed, 156 insertions(+)
> create mode 100644 drivers/mfd/act8945a.c
> create mode 100644 include/linux/mfd/act8945a.h
>
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 9581ebb..018c72d 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -18,6 +18,14 @@ config MFD_CS5535
> This is the core driver for CS5535/CS5536 MFD functions. This is
> necessary for using the board's GPIO and MFGPT functionality.
>
> +config MFD_ACT8945A
> + bool "Active-semi ACT8945A"
> + select MFD_CORE
> + select REGMAP_I2C
> + depends on I2C && OF
> + help
> + Support for the ACT8945A PMIC from Active-Semi

Checkpatch usually complains about single line helps.

> config MFD_AS3711
> bool "AMS AS3711"
> select MFD_CORE
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index 0f230a6..2f1ca82 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -6,6 +6,7 @@
> obj-$(CONFIG_MFD_88PM860X) += 88pm860x.o
> obj-$(CONFIG_MFD_88PM800) += 88pm800.o 88pm80x.o
> obj-$(CONFIG_MFD_88PM805) += 88pm805.o 88pm80x.o
> +obj-$(CONFIG_MFD_ACT8945A) += act8945a.o
> obj-$(CONFIG_MFD_SM501) += sm501.o
> obj-$(CONFIG_MFD_ASIC3) += asic3.o tmio_core.o
> obj-$(CONFIG_MFD_BCM590XX) += bcm590xx.o
> diff --git a/drivers/mfd/act8945a.c b/drivers/mfd/act8945a.c
> new file mode 100644
> index 0000000..b9b8685
> --- /dev/null
> +++ b/drivers/mfd/act8945a.c
> @@ -0,0 +1,122 @@
> +/*
> + * MFD driver for Active-semi ACT8945a PMIC
> + *
> + * Copyright (C) 2015 Atmel Corporation.

Please update this.

> + * Wenyou Yang <wenyou.yang@xxxxxxxxx>

* Author: Wenyou Yang <wenyou.yang@xxxxxxxxx>

> + * This software is licensed under the terms of the GNU General Public
> + * License version 2, as published by the Free Software Foundation, and
> + * may be copied, distributed, and modified under those terms.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.

This is the long version. Any chance it can be shortened?

> + */
> +
> +#include <linux/i2c.h>
> +#include <linux/mfd/act8945a.h>
> +#include <linux/mfd/core.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/regmap.h>
> +
> +static const struct mfd_cell act8945a_devs[] = {
> + {
> + .name = "act8945a-pmic",
> + .of_compatible = "active-semi,act8945a-regulator",
> + },
> + {
> + .name = "act8945a-charger",
> + .of_compatible = "active-semi,act8945a-charger",
> + },
> +};
> +
> +static const struct regmap_config act8945a_regmap_config = {
> + .reg_bits = 8,
> + .val_bits = 8,
> +};
> +
> +static int act8945a_i2c_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + struct act8945a_dev *act8945a;
> + int ret;
> +
> + act8945a = devm_kzalloc(&client->dev, sizeof(*act8945a), GFP_KERNEL);
> + if (act8945a == NULL)

if (!act8945a)

> + return -ENOMEM;
> +
> + i2c_set_clientdata(client, act8945a);
> +
> + act8945a->dev = &client->dev;
> + act8945a->i2c_client = client;

If you're saving 'client' already, you don't need to save 'dev' too,
as one can be retrieved from the other.

> + act8945a->regmap = devm_regmap_init_i2c(client,
> + &act8945a_regmap_config);

Don't we have a generic call to obtain a single 8bit register yet?

> + if (IS_ERR(act8945a->regmap)) {
> + ret = PTR_ERR(act8945a->regmap);
> + dev_err(&client->dev, "regmap init failed: %d\n", ret);
> + return ret;
> + }
> +
> + ret = mfd_add_devices(act8945a->dev, -1, act8945a_devs,

Please use the correct defines, instead of '-1'.

> + ARRAY_SIZE(act8945a_devs), NULL, 0, NULL);
> + if (ret < 0) {

if (ret)

> + dev_err(&client->dev, "mfd_add_devices failed: %d\n", ret);

Be more explicit.

"Failed to add sub devices".

> + return ret;
> + }
> +
> + dev_info(&client->dev, "added %zu mfd sub-devices\n",
> + ARRAY_SIZE(act8945a_devs));

This serves no one, please remove.

> + return 0;
> +
> +}
> +
> +static int act8945a_i2c_remove(struct i2c_client *i2c)
> +{
> + struct act8945a_dev *act8945a = i2c_get_clientdata(i2c);
> +
> + mfd_remove_devices(act8945a->dev);

mfd_remove_devices(i2c->dev);

> + return 0;
> +}
> +
> +static const struct i2c_device_id act8945a_i2c_id[] = {
> + { "act8945a", 0 },
> + {}
> +};
> +MODULE_DEVICE_TABLE(i2c, act8945a_i2c_id);
> +
> +static const struct of_device_id act8945a_of_match[] = {
> + {.compatible = "active-semi,act8945a", },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, act8945a_of_match);
> +
> +static struct i2c_driver act8945a_i2c_driver = {
> + .driver = {
> + .name = "act8945a",
> + .owner = THIS_MODULE,

Remove this line, it's taken care of elsewhere.

> + .of_match_table = of_match_ptr(act8945a_of_match),
> + },
> + .probe = act8945a_i2c_probe,
> + .remove = act8945a_i2c_remove,
> + .id_table = act8945a_i2c_id,
> +};
> +
> +static int __init act8945a_i2c_init(void)
> +{
> + return i2c_add_driver(&act8945a_i2c_driver);
> +}
> +subsys_initcall(act8945a_i2c_init);
> +
> +static void __exit act8945a_i2c_exit(void)
> +{
> + i2c_del_driver(&act8945a_i2c_driver);
> +}
> +module_exit(act8945a_i2c_exit);
> +
> +MODULE_DESCRIPTION("ACT8945A PMIC multi-function driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Wenyou Yang <wenyou.yang@xxxxxxxxx>");
> diff --git a/include/linux/mfd/act8945a.h b/include/linux/mfd/act8945a.h
> new file mode 100644
> index 0000000..5b18d16
> --- /dev/null
> +++ b/include/linux/mfd/act8945a.h
> @@ -0,0 +1,25 @@
> +/*
> + * MFD for Active-semi ACT8945A PMIC
> + *
> + * Copyright (C) 2015 Atmel Corporation.

Please update this.

> + * This software is licensed under the terms of the GNU General Public
> + * License version 2, as published by the Free Software Foundation, and
> + * may be copied, distributed, and modified under those terms.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#ifndef _LINUX_MFD_ACT8945A_H
> +#define _LINUX_MFD_ACT8945A_H
> +
> +struct act8945a_dev {
> + struct device *dev;

I don't think you need this.

> + struct i2c_client *i2c_client;

Where is this used?

> + struct regmap *regmap;

Where is this used?

> +};
> +
> +#endif

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org â Open source software for ARM SoCs
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