Re: [PATCH v4 4/8] mfd: hi6421-pmic: add support for HiSilicon Hi6421v530

From: Lee Jones
Date: Tue Jun 06 2017 - 09:54:55 EST


On Tue, 06 Jun 2017, Guodong Xu wrote:

> Add support for HiSilicon Hi6421v530 PMIC. Hi6421v530 communicates with
> main SoC via memory-mapped I/O.
>
> Hi6421v530 and Hi6421 are PMIC chips from the same vendor, HiSilicon,
> but at different revisions. They share the same memory-mapped I/O
> design. They differ in integrated devices, such as regulator details,
> LDO voltage points.
>
> Signed-off-by: Wang Xiaoyin <hw.wangxiaoyin@xxxxxxxxxxxxx>
> Signed-off-by: Guodong Xu <guodong.xu@xxxxxxxxxx>
> ---
> drivers/mfd/hi6421-pmic-core.c | 68 ++++++++++++++++++++++++++++++-----------
> include/linux/mfd/hi6421-pmic.h | 5 +++
> 2 files changed, 55 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/mfd/hi6421-pmic-core.c b/drivers/mfd/hi6421-pmic-core.c
> index b1139d4..4568a43 100644
> --- a/drivers/mfd/hi6421-pmic-core.c
> +++ b/drivers/mfd/hi6421-pmic-core.c

[...]

> static int hi6421_pmic_probe(struct platform_device *pdev)
> {
> struct hi6421_pmic *pmic;
> struct resource *res;
> + const struct of_device_id *id;
> + const struct mfd_cell *subdevs;
> void __iomem *base;
> - int ret;
> + int n_subdevs, ret;
> +
> + id = of_match_device(of_hi6421_pmic_match, &pdev->dev);
> + if (!id)
> + return -EINVAL;
>
> pmic = devm_kzalloc(&pdev->dev, sizeof(*pmic), GFP_KERNEL);
> if (!pmic)
> @@ -57,18 +80,33 @@ static int hi6421_pmic_probe(struct platform_device *pdev)
> return PTR_ERR(pmic->regmap);
> }
>
> - /* set over-current protection debounce 8ms */
> - regmap_update_bits(pmic->regmap, HI6421_OCP_DEB_CTRL_REG,
> + platform_set_drvdata(pdev, pmic);
> +
> + switch ((unsigned long)id->data) {

Whilst this is not a blocker, it would be nicer to place this into a
'type' variable, in order to clarify what data you are using.

> + case HI6421:
> + /* set over-current protection debounce 8ms */
> + regmap_update_bits(pmic->regmap, HI6421_OCP_DEB_CTRL_REG,
> (HI6421_OCP_DEB_SEL_MASK
> | HI6421_OCP_EN_DEBOUNCE_MASK
> | HI6421_OCP_AUTO_STOP_MASK),
> (HI6421_OCP_DEB_SEL_8MS
> | HI6421_OCP_EN_DEBOUNCE_ENABLE));
>
> - platform_set_drvdata(pdev, pmic);
> + subdevs = hi6421_devs;
> + n_subdevs = ARRAY_SIZE(hi6421_devs);
> + break;
> + case HI6421_V530:
> + subdevs = hi6421v530_devs;
> + n_subdevs = ARRAY_SIZE(hi6421v530_devs);
> + break;
> + default:
> + dev_err(&pdev->dev, "Unknown device type %ld\n",
> + (unsigned long)id->data);
> + return -EINVAL;
> + }
>
> - ret = devm_mfd_add_devices(&pdev->dev, 0, hi6421_devs,
> - ARRAY_SIZE(hi6421_devs), NULL, 0, NULL);
> + ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE,
> + subdevs, n_subdevs, NULL, 0, NULL);
> if (ret) {
> dev_err(&pdev->dev, "Failed to add child devices: %d\n", ret);
> return ret;
> @@ -77,16 +115,10 @@ static int hi6421_pmic_probe(struct platform_device *pdev)
> return 0;
> }
>
> -static const struct of_device_id of_hi6421_pmic_match_tbl[] = {
> - { .compatible = "hisilicon,hi6421-pmic", },
> - { },
> -};
> -MODULE_DEVICE_TABLE(of, of_hi6421_pmic_match_tbl);
> -
> static struct platform_driver hi6421_pmic_driver = {
> .driver = {
> - .name = "hi6421_pmic",
> - .of_match_table = of_hi6421_pmic_match_tbl,
> + .name = "hi6421_pmic",
> + .of_match_table = of_hi6421_pmic_match,
> },
> .probe = hi6421_pmic_probe,
> };
> diff --git a/include/linux/mfd/hi6421-pmic.h b/include/linux/mfd/hi6421-pmic.h
> index 587273e..2457438 100644
> --- a/include/linux/mfd/hi6421-pmic.h
> +++ b/include/linux/mfd/hi6421-pmic.h
> @@ -38,4 +38,9 @@ struct hi6421_pmic {
> struct regmap *regmap;
> };
>
> +enum hi6421_type {
> + HI6421 = 1,
> + HI6421_V530 = 2,
> +};
> +

As programmers we usually start counting at 0. Then you can rely on
the C standard to populate the remaining values.

Something like:

enum hi6421_type {
HI6421 = 0,
HI6421_V530,
};

... is more normal.

> #endif /* __HI6421_PMIC_H */

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