Re: [PATCH v3 1/3] mfd: wm831x: Add basic device tree binding

[Lee Jones]

On Mon, 06 Mar 2017, Charles Keepax wrote:

> Add the basic ability to register the device through device tree, more
> work is needed to get each individual sub-driver functioning correctly
> but this is enough to get the device to probe from device tree.
> 
> Signed-off-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
> ---
> 
> No changes since v2.
> 
>  drivers/mfd/wm831x-core.c       | 32 +++++++++++++++++++++++++++++++-
>  drivers/mfd/wm831x-i2c.c        |  9 ++++++++-
>  drivers/mfd/wm831x-irq.c        |  6 +++---
>  drivers/mfd/wm831x-spi.c        |  6 +++++-
>  include/linux/mfd/wm831x/core.h | 15 +++++++++++++++
>  5 files changed, 62 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/mfd/wm831x-core.c b/drivers/mfd/wm831x-core.c
> index 3e0e99e..21d3cdd 100644
> --- a/drivers/mfd/wm831x-core.c
> +++ b/drivers/mfd/wm831x-core.c
> @@ -19,6 +19,8 @@
>  #include <linux/mfd/core.h>
>  #include <linux/slab.h>
>  #include <linux/err.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
>  
>  #include <linux/mfd/wm831x/core.h>
>  #include <linux/mfd/wm831x/pdata.h>
> @@ -1613,6 +1615,31 @@ struct regmap_config wm831x_regmap_config = {
>  };
>  EXPORT_SYMBOL_GPL(wm831x_regmap_config);
>  
> +#ifdef CONFIG_OF
> +const struct of_device_id wm831x_of_match[] = {
> +	{ .compatible = "wlf,wm8310", .data = (void *)WM8310 },
> +	{ .compatible = "wlf,wm8311", .data = (void *)WM8311 },
> +	{ .compatible = "wlf,wm8312", .data = (void *)WM8312 },
> +	{ .compatible = "wlf,wm8320", .data = (void *)WM8320 },
> +	{ .compatible = "wlf,wm8321", .data = (void *)WM8321 },
> +	{ .compatible = "wlf,wm8325", .data = (void *)WM8325 },
> +	{ .compatible = "wlf,wm8326", .data = (void *)WM8326 },
> +	{ },
> +};
> +EXPORT_SYMBOL_GPL(wm831x_of_match);
> +
> +int wm831x_of_get_type(struct device *dev)
> +{
> +	const struct of_device_id *id = of_match_device(wm831x_of_match, dev);
> +
> +	if (id)
> +		return (unsigned long)id->data;
> +	else

This is not possible.

> +		return 0;
> +}
> +EXPORT_SYMBOL_GPL(wm831x_of_get_type);

No need for this function and certainly no requirement to export it.

> +#endif
> +
>  /*
>   * Instantiate the generic non-control parts of the device.
>   */
> @@ -1628,7 +1655,10 @@ int wm831x_device_init(struct wm831x *wm831x, unsigned long id, int irq)

You can expand 'id' to 'type' now.

>  	dev_set_drvdata(wm831x->dev, wm831x);
>  
>  	if (pdata)
> -		wm831x->soft_shutdown = pdata->soft_shutdown;
> +		memcpy(&wm831x->pdata, pdata, sizeof(*pdata));
> +	pdata = &wm831x->pdata;

We normally deal with pdata in .probe().

It makes sense to group it with your 'get_type' code.

> +	wm831x->soft_shutdown = pdata->soft_shutdown;
>  
>  	ret = wm831x_reg_read(wm831x, WM831X_PARENT_ID);
>  	if (ret < 0) {
> diff --git a/drivers/mfd/wm831x-i2c.c b/drivers/mfd/wm831x-i2c.c
> index 824bcba..b2acd92 100644
> --- a/drivers/mfd/wm831x-i2c.c
> +++ b/drivers/mfd/wm831x-i2c.c
> @@ -28,8 +28,14 @@ static int wm831x_i2c_probe(struct i2c_client *i2c,
>  			    const struct i2c_device_id *id)
>  {
>  	struct wm831x *wm831x;
> +	enum wm831x_parent type;
>  	int ret;
>  
> +	if (i2c->dev.of_node)
> +		type = (enum wm831x_parent)wm831x_of_get_type(&i2c->dev);

Move the 'get_type' code here instead and store the type into device
data i.e. wm831x.

> +	else
> +		type = (enum wm831x_parent)id->driver_data;
> +
>  	wm831x = devm_kzalloc(&i2c->dev, sizeof(struct wm831x), GFP_KERNEL);
>  	if (wm831x == NULL)
>  		return -ENOMEM;
> @@ -45,7 +51,7 @@ static int wm831x_i2c_probe(struct i2c_client *i2c,
>  		return ret;
>  	}
>  
> -	return wm831x_device_init(wm831x, id->driver_data, i2c->irq);
> +	return wm831x_device_init(wm831x, type, i2c->irq);
>  }
>  
>  static int wm831x_i2c_remove(struct i2c_client *i2c)
> @@ -94,6 +100,7 @@ static struct i2c_driver wm831x_i2c_driver = {
>  	.driver = {
>  		.name = "wm831x",
>  		.pm = &wm831x_pm_ops,
> +		.of_match_table = of_match_ptr(wm831x_of_match),
>  	},
>  	.probe = wm831x_i2c_probe,
>  	.remove = wm831x_i2c_remove,
> diff --git a/drivers/mfd/wm831x-irq.c b/drivers/mfd/wm831x-irq.c
> index dfea8b9..c01239a 100644
> --- a/drivers/mfd/wm831x-irq.c
> +++ b/drivers/mfd/wm831x-irq.c
> @@ -564,7 +564,7 @@ static const struct irq_domain_ops wm831x_irq_domain_ops = {
>  
>  int wm831x_irq_init(struct wm831x *wm831x, int irq)
>  {
> -	struct wm831x_pdata *pdata = dev_get_platdata(wm831x->dev);
> +	struct wm831x_pdata *pdata = &wm831x->pdata;
>  	struct irq_domain *domain;
>  	int i, ret, irq_base;
>  
> @@ -579,7 +579,7 @@ int wm831x_irq_init(struct wm831x *wm831x, int irq)
>  	}
>  
>  	/* Try to dynamically allocate IRQs if no base is specified */
> -	if (pdata && pdata->irq_base) {
> +	if (pdata->irq_base) {
>  		irq_base = irq_alloc_descs(pdata->irq_base, 0,
>  					   WM831X_NUM_IRQS, 0);
>  		if (irq_base < 0) {
> @@ -608,7 +608,7 @@ int wm831x_irq_init(struct wm831x *wm831x, int irq)
>  		return -EINVAL;
>  	}
>  
> -	if (pdata && pdata->irq_cmos)
> +	if (pdata->irq_cmos)
>  		i = 0;
>  	else
>  		i = WM831X_IRQ_OD;
> diff --git a/drivers/mfd/wm831x-spi.c b/drivers/mfd/wm831x-spi.c
> index 80482ae..44c6eec 100644
> --- a/drivers/mfd/wm831x-spi.c
> +++ b/drivers/mfd/wm831x-spi.c
> @@ -28,7 +28,10 @@ static int wm831x_spi_probe(struct spi_device *spi)
>  	enum wm831x_parent type;
>  	int ret;
>  
> -	type = (enum wm831x_parent)id->driver_data;
> +	if (spi->dev.of_node)
> +		type = (enum wm831x_parent)wm831x_of_get_type(&spi->dev);
> +	else
> +		type = (enum wm831x_parent)id->driver_data;
>  
>  	wm831x = devm_kzalloc(&spi->dev, sizeof(struct wm831x), GFP_KERNEL);
>  	if (wm831x == NULL)
> @@ -97,6 +100,7 @@ static struct spi_driver wm831x_spi_driver = {
>  	.driver = {
>  		.name	= "wm831x",
>  		.pm	= &wm831x_spi_pm,
> +		.of_match_table = of_match_ptr(wm831x_of_match),
>  	},
>  	.id_table	= wm831x_spi_ids,
>  	.probe		= wm831x_spi_probe,
> diff --git a/include/linux/mfd/wm831x/core.h b/include/linux/mfd/wm831x/core.h
> index 76c2264..752a722 100644
> --- a/include/linux/mfd/wm831x/core.h
> +++ b/include/linux/mfd/wm831x/core.h
> @@ -21,6 +21,8 @@
>  #include <linux/list.h>
>  #include <linux/regmap.h>
>  #include <linux/mfd/wm831x/auxadc.h>
> +#include <linux/mfd/wm831x/pdata.h>
> +#include <linux/of.h>
>  
>  /*
>   * Register values.
> @@ -367,6 +369,8 @@ struct wm831x {
>  
>  	struct regmap *regmap;
>  
> +	struct wm831x_pdata pdata;
> +
>  	int irq;  /* Our chip IRQ */
>  	struct mutex irq_lock;
>  	struct irq_domain *irq_domain;
> @@ -427,4 +431,15 @@ static inline int wm831x_irq(struct wm831x *wm831x, int irq)
>  
>  extern struct regmap_config wm831x_regmap_config;
>  
> +extern const struct of_device_id wm831x_of_match[];
> +
> +#ifdef CONFIG_OF
> +int wm831x_of_get_type(struct device *dev);
> +#else
> +static inline int wm831x_of_get_type(struct device *dev)
> +{
> +	return 0;
> +}
> +#endif

No need.

>  #endif

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