Re: [PATCH v5 2/3] mfd: lp873x: Add lp873x PMIC support

[Lee Jones]

On Wed, 29 Jun 2016, Keerthy wrote:

> The LP873X chip is a power management IC for Portable Navigation Systems
>     and Tablet Computing devices. It contains the following components:
> 
>      - Regulators.
>      - Configurable General Purpose Output Signals(GPO).
> 
> PMIC interacts with the main processor through i2c. PMIC has
> couple of LDOs(Linear Regulators), couple of BUCKs (Step-Down DC-DC
> Converter Cores) and GPOs(General Purpose Output Signals).
> 
> Signed-off-by: Keerthy <j-keerthy@xxxxxx>
> ---
> 
> Changes in v4:
> 
>   * Added Author.
>   * Added the mfd_cell for gpio.
> 
> Changes in v3:
> 
>   * Reordered the probe code.
>   * Fixed Typo in Kconfig description.
>   * Removed unused member from struct lp873x.
> 
>  drivers/mfd/Kconfig        |  14 +++
>  drivers/mfd/Makefile       |   2 +
>  drivers/mfd/lp873x.c       |  99 +++++++++++++++++
>  include/linux/mfd/lp873x.h | 264 +++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 379 insertions(+)
>  create mode 100644 drivers/mfd/lp873x.c
>  create mode 100644 include/linux/mfd/lp873x.h
> 
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 9987d86..e68ac28 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -1221,6 +1221,20 @@ config MFD_TPS65217
>  	  This driver can also be built as a module.  If so, the module
>  	  will be called tps65217.
>  
> +config MFD_LP873X

Nicer as MFD_TI_LP873X I think.

> +	tristate "TI LP873X Power Management IC"
> +	depends on I2C
> +	select MFD_CORE
> +	select REGMAP_I2C
> +	help
> +	  If you say yes here then you get support for the LP873X series of
> +	  power management integrated circuits(PMIC).

Power Management Integrated Circuits (PMIC).

> +	  These include voltage regulators, Thermal protection, Configurable
> +	  general purpose outputs(GPO) that are used in portable devices.

Some here.  Please standardise your capitalisation.

> +	  This driver can also be built as a module.  If so, the module
> +	  will be called lp873x.
> +
>  config MFD_TPS65218
>  	tristate "TI TPS65218 Power Management chips"
>  	depends on I2C
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index 2ba3ba3..7d9b965 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -22,6 +22,8 @@ obj-$(CONFIG_HTC_EGPIO)		+= htc-egpio.o
>  obj-$(CONFIG_HTC_PASIC3)	+= htc-pasic3.o
>  obj-$(CONFIG_HTC_I2CPLD)	+= htc-i2cpld.o
>  
> +obj-$(CONFIG_MFD_LP873X)	+= lp873x.o
> +
>  obj-$(CONFIG_MFD_DAVINCI_VOICECODEC)	+= davinci_voicecodec.o
>  obj-$(CONFIG_MFD_DM355EVM_MSP)	+= dm355evm_msp.o
>  obj-$(CONFIG_MFD_TI_AM335X_TSCADC)	+= ti_am335x_tscadc.o
> diff --git a/drivers/mfd/lp873x.c b/drivers/mfd/lp873x.c
> new file mode 100644
> index 0000000..54ed0ce
> --- /dev/null
> +++ b/drivers/mfd/lp873x.c
> @@ -0,0 +1,99 @@
> +/*
> + * Copyright (C) 2016 Texas Instruments Incorporated - http://www.ti.com/
> + *
> + * Author: Keerthy <j-keerthy@xxxxxx>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation version 2.
> + *
> + * This program is distributed "as is" WITHOUT ANY WARRANTY of any
> + * kind, whether express or implied; without even the implied warranty
> + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/interrupt.h>
> +#include <linux/mfd/core.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/regmap.h>
> +
> +#include <linux/mfd/lp873x.h>
> +
> +static const struct regmap_config lp873x_regmap_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +	.max_register = LP873X_REG_MAX,
> +};
> +
> +static const struct mfd_cell lp873x_cells[] = {
> +	{ .name = "lp873x-regulator", },
> +	{ .name = "lp873x-gpio", },
> +};
> +
> +static int lp873x_probe(struct i2c_client *client,
> +			const struct i2c_device_id *ids)
> +{
> +	struct lp873x *lp873;
> +	int ret;
> +	unsigned int otpid;
> +
> +	lp873 = devm_kzalloc(&client->dev, sizeof(*lp873), GFP_KERNEL);
> +	if (!lp873)
> +		return -ENOMEM;
> +
> +	lp873->dev = &client->dev;
> +
> +	lp873->regmap = devm_regmap_init_i2c(client, &lp873x_regmap_config);
> +	if (IS_ERR(lp873->regmap)) {
> +		ret = PTR_ERR(lp873->regmap);
> +		dev_err(lp873->dev, "Failed to initialize register map: %d\n",
> +			ret);

Nit: I'd prefer you break after "->dev,".

> +		return ret;
> +	}
> +
> +	mutex_init(&lp873->lp873_lock);

How many locks do you have in 'struct lp873x'?

I suggest that 'lock' will do fine.

> +	ret = regmap_read(lp873->regmap, LP873X_REG_OTP_REV, &otpid);
> +	if (ret) {
> +		dev_err(lp873->dev, "Failed to read OTP ID\n");
> +		return ret;
> +	}
> +
> +	lp873->rev = otpid & LP873X_OTP_REV_OTP_ID;
> +	i2c_set_clientdata(client, lp873);
> +	ret = mfd_add_devices(lp873->dev, PLATFORM_DEVID_AUTO, lp873x_cells,
> +			      ARRAY_SIZE(lp873x_cells), NULL, 0, NULL);
> +
> +	return ret;
> +}
> +
> +static const struct of_device_id of_lp873x_match_table[] = {
> +	{ .compatible = "ti,lp8733", },
> +	{ .compatible = "ti,lp8732", },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, of_lp873x_match_table);
> +
> +static const struct i2c_device_id lp873x_id_table[] = {
> +	{ "lp873x", LP873X },
> +	{ "lp8732", LP873X },
> +	{ "lp8733", LP873X },

Do you use these IDs at any point?

[...]

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