Re: [PATCH v2 1/4] mfd: add LP3943 MFD driver

[Lee Jones <lee.jones@linaro.org>]

> Cc: Lee Jones <lee.jones@linaro.org>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Cc: Mark Brown <broonie@kernel.org>
> Cc: Samuel Ortiz <sameo@linux.intel.com>
> Cc: Thierry Reding <thierry.reding@gmail.com>
> Signed-off-by: Milo Kim <milo.kim@ti.com>
> ---
>  drivers/mfd/Kconfig        |   11 +++
>  drivers/mfd/Makefile       |    1 +
>  drivers/mfd/lp3943.c       |  165 ++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/mfd/lp3943.h |  115 ++++++++++++++++++++++++++++++
>  4 files changed, 292 insertions(+)
>  create mode 100644 drivers/mfd/lp3943.c
>  create mode 100644 include/linux/mfd/lp3943.h

<snip> * looks good up to me up to here *

Although, I think the 0 = 1, 1 = 2 ... stuff is really confusing. Is
there nothing we can do about that?

> +static int lp3943_probe(struct i2c_client *cl, const struct i2c_device_id *id)
> +{
> +	struct lp3943 *lp3943;
> +	int ret;
> +
> +	lp3943 = devm_kzalloc(&cl->dev, sizeof(*lp3943), GFP_KERNEL);
> +	if (!lp3943)
> +		return -ENOMEM;
> +
> +	lp3943->regmap = devm_regmap_init_i2c(cl, &lp3943_regmap_config);
> +	if (IS_ERR(lp3943->regmap)) {
> +		ret = PTR_ERR(lp3943->regmap);

Bit of a nit. 

Why don't you: return PTR_ERR(lp3943->regmap);

> +		dev_err(&cl->dev, "Regmap init error: %d\n", ret);
> +		return ret;
> +	}
> +
> +	lp3943->pdata = cl->dev.platform_data;

Can you change this to use the helper?

dev_get_platdata()

> +	lp3943->dev = &cl->dev;
> +	lp3943->mux_cfg = lp3943_mux_cfg;
> +	i2c_set_clientdata(cl, lp3943);
> +
> +	ret = mfd_add_devices(lp3943->dev, -1, lp3943_devs,
> +			ARRAY_SIZE(lp3943_devs), NULL, 0, NULL);
> +	if (ret) {
> +		dev_err(lp3943->dev, "failed to add MFD devices: %d\n", ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int lp3943_remove(struct i2c_client *cl)
> +{
> +	struct lp3943 *lp3943 = i2c_get_clientdata(cl);
> +
> +	mfd_remove_devices(lp3943->dev);
> +	return 0;
> +}
> +
> +static const struct i2c_device_id lp3943_ids[] = {
> +	{ "lp3943", 0 },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(i2c, lp3943_ids);

Are we expecting this driver to support more devices?

> +static const struct of_device_id lp3943_dt_ids[] = {
> +	{ .compatible = "ti,lp3943", },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(of, lp3943_dt_ids);
> +
> +static struct i2c_driver lp3943_driver = {
> +	.driver = {
> +		.name = "lp3943",
> +		.owner = THIS_MODULE,
> +		.of_match_table = of_match_ptr(lp3943_dt_ids),
> +	},
> +	.probe = lp3943_probe,
> +	.remove = lp3943_remove,
> +	.id_table = lp3943_ids,
> +};
> +
> +static int __init lp3943_init(void)
> +{
> +	return i2c_add_driver(&lp3943_driver);
> +}
> +subsys_initcall(lp3943_init);
> +
> +static void __exit lp3943_exit(void)
> +{
> +	i2c_del_driver(&lp3943_driver);
> +}
> +module_exit(lp3943_exit);

I think you want to replace:
  lp3943_init()
  lp3943_exit

With:
  module_i2c_driver()

> +MODULE_DESCRIPTION("LP3943 MFD Core Driver");
> +MODULE_AUTHOR("Milo Kim");
> +MODULE_LICENSE("GPL");

-- 
Lee Jones
Linaro ST-Ericsson Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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