[PATCH v3 4/5] regulator: max14577: Add regulator driver for Maxim 14577

Lee Jones
2013-11-22T10:15:51Z

On Fri, 22 Nov 2013, Krzysztof Kozlowski wrote:

> MAX14577 chip is a multi-function device which includes MUIC,
> charger and voltage regulator. The driver is located in drivers/mfd.
>
> This patch adds regulator driver for MAX14577 chip. There are two
> regulators in this chip:
> 1. Safeout LDO with constant voltage output of 4.9V. It can be only
> enabled or disabled.
> 2. Current regulator for the charger. It provides current from 90mA up
> to 950mA.
> Driver supports Device Tree.
>
> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
> ---
> drivers/regulator/Kconfig | 7 ++
> drivers/regulator/Makefile | 1 +
> drivers/regulator/max14577.c | 272 ++++++++++++++++++++++++++++++++++++++++++
> include/linux/mfd/max14577.h | 1 -
> 4 files changed, 280 insertions(+), 1 deletion(-)
> create mode 100644 drivers/regulator/max14577.c

<snip>

> +#ifdef CONFIG_OF
> +static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev,
> + struct max14577_platform_data *pdata)
> +{
> + struct max14577 *max14577 = dev_get_drvdata(pdev->dev.parent);
> + struct device_node *np;
> + struct max14577_regulator_platform_data *reg_pdata;
> + struct of_regulator_match rmatch;
> + int i, ret;
> +
> + np = of_get_child_by_name(max14577->dev->of_node, "regulators");
> + if (!np)
> + return -EINVAL;

No need to do this. If instead you use a compatible string and set
it's MFD cell's .of_compatible property, the MFD core will set
pdev->dev.of_node for you.

> + reg_pdata = devm_kzalloc(&pdev->dev, sizeof(*reg_pdata) *
> + ARRAY_SIZE(supported_regulators), GFP_KERNEL);
> + if (!reg_pdata)
> + return -ENOMEM;
> +
> + for (i = 0; i < ARRAY_SIZE(supported_regulators); i++) {
> + rmatch.name = supported_regulators[i].name;
> + ret = of_regulator_match(&pdev->dev, np, &rmatch, 1);
> + if (ret != 1)
> + continue;
> + dev_dbg(&pdev->dev, "Found regulator %d/%s\n",
> + supported_regulators[i].id,
> + supported_regulators[i].name);
> + reg_pdata[i].id = supported_regulators[i].id;
> + reg_pdata[i].initdata = rmatch.init_data;
> + reg_pdata[i].of_node = rmatch.of_node;
> + }
> +
> + pdata->regulators = reg_pdata;
> +
> + return 0;
> +}
> +#else
> +static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev,
> + struct max14577_platform_data *pdata)
> +{
> + return 0;
> +}
> +#endif

No need for this either. Just check for the device's of_node.

> +static int max14577_regulator_probe(struct platform_device *pdev)
> +{
> + struct max14577 *max14577 = dev_get_drvdata(pdev->dev.parent);
> + struct max14577_platform_data *pdata = dev_get_platdata(max14577->dev);
> + int i, size;
> + struct regulator_config config = {};
> + struct regulator_dev **regulators;
> +
> + if (!pdata) {
> + /* Parent must provide pdata */
> + dev_err(&pdev->dev, "No MFD driver platform data found.\n");
> + return -ENODEV;
> + }
> +
> + if (max14577->dev->of_node) {
> + int ret = max14577_regulator_dt_parse_pdata(pdev, pdata);

This will overwrite pdata which is wrong.

pdata should always take precedence over DT.

<snip>

> + for (i = 0; i < ARRAY_SIZE(supported_regulators); i++) {
> + /*
> + * Index of supported_regulators[] is also the id and must
> + * match index of pdata->regulators[].
> + */
> + config.init_data = pdata->regulators[i].initdata;
> + config.of_node = pdata->regulators[i].of_node;

I still thing this is superfluous. Why don't you run though the nodes
here instead of doing it in MFD and passing this stuff through?

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org ? Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog