Re: [PATCH v4 10/10] power: bq24257: Add platform data based initialization

[Andreas Dannenberg <dannenberg@ti.com>]

On Wed, Sep 16, 2015 at 05:31:58PM +0900, Krzysztof Kozlowski wrote:
> On 16.09.2015 02:58, Andreas Dannenberg wrote:
> > The patch adds a way to setup and initialize the device through the use
> > of platform data with configuration options equivalent to when using
> > device firmware (DT or ACPI) for systems where this is not available.
> > 
> > Signed-off-by: Andreas Dannenberg <dannenberg@ti.com>
> > ---
> >  drivers/power/bq24257_charger.c       | 117 ++++++++++++++++++++++++++++++----
> >  include/linux/power/bq24257_charger.h |  29 +++++++++
> >  2 files changed, 135 insertions(+), 11 deletions(-)
> >  create mode 100644 include/linux/power/bq24257_charger.h
> > 
> > diff --git a/drivers/power/bq24257_charger.c b/drivers/power/bq24257_charger.c
> > index a0cb33c..fa18b1f 100644
> > --- a/drivers/power/bq24257_charger.c
> > +++ b/drivers/power/bq24257_charger.c
> > @@ -27,10 +27,13 @@
> >  #include <linux/gpio/consumer.h>
> >  #include <linux/interrupt.h>
> >  #include <linux/delay.h>
> > +#include <linux/gpio.h>
> >  
> >  #include <linux/acpi.h>
> >  #include <linux/of.h>
> >  
> > +#include <linux/power/bq24257_charger.h>
> > +
> >  #define BQ24257_REG_1			0x00
> >  #define BQ24257_REG_2			0x01
> >  #define BQ24257_REG_3			0x02
> > @@ -877,28 +880,112 @@ static int bq24257_power_supply_init(struct bq24257_device *bq)
> >  
> >  static int bq24257_irq_probe(struct bq24257_device *bq)
> >  {
> > +	struct bq24257_platform_data *pdata = bq->client->dev.platform_data;
> >  	struct gpio_desc *stat_irq;
> > +	int ret;
> > +
> > +	if (!pdata) {
> > +		stat_irq = devm_gpiod_get_index(bq->dev, BQ24257_STAT_IRQ, 0,
> > +						GPIOD_IN);
> > +		if (IS_ERR(stat_irq)) {
> > +			dev_err(bq->dev, "could not probe stat_irq pin\n");
> > +			return PTR_ERR(stat_irq);
> > +		}
> > +	} else {
> > +		if (!gpio_is_valid(pdata->stat_gpio)) {
> > +			dev_err(bq->dev, "invalid stat_irq pin\n");
> > +			return -EINVAL;
> > +		}
> >  
> > -	stat_irq = devm_gpiod_get_index(bq->dev, BQ24257_STAT_IRQ, 0, GPIOD_IN);
> > -	if (IS_ERR(stat_irq)) {
> > -		dev_err(bq->dev, "could not probe stat_irq pin\n");
> > -		return PTR_ERR(stat_irq);
> > +		ret = devm_gpio_request_one(bq->dev, pdata->stat_gpio,
> > +					    GPIOD_IN, BQ24257_STAT_IRQ);
> 
> That should be GPIOF_* flag, not GPIOD.

Good catch. Looks like it worked because the definitions happen to result
in the same value.

> > +		if (ret) {
> > +			dev_err(bq->dev, "stat_irq pin request failed\n");
> > +			return ret;
> > +		}
> > +
> > +		stat_irq = gpio_to_desc(pdata->stat_gpio);
> > +		if (!stat_irq) {
> > +			dev_err(bq->dev,
> > +				"could not get stat_irq pin descriptor\n");
> > +			return -EINVAL;
> > +		}
> >  	}
> >  
> > +	dev_dbg(bq->dev, "probed stat_irq pin = %d", desc_to_gpio(stat_irq));
> > +
> >  	return gpiod_to_irq(stat_irq);
> >  }
> >  
> >  static int bq24257_pg_gpio_probe(struct bq24257_device *bq)
> >  {
> > -	bq->pg = devm_gpiod_get_index(bq->dev, BQ24257_PG_GPIO, 0, GPIOD_IN);
> > -	if (IS_ERR(bq->pg)) {
> > -		dev_info(bq->dev, "could not probe PG pin\n");
> > -		return PTR_ERR(bq->pg);
> > +	struct bq24257_platform_data *pdata = bq->client->dev.platform_data;
> > +	int ret;
> > +
> > +	if (!pdata) {
> > +		bq->pg = devm_gpiod_get_index(bq->dev, BQ24257_PG_GPIO, 0,
> > +					      GPIOD_IN);
> > +		if (IS_ERR(bq->pg)) {
> > +			dev_info(bq->dev, "could not probe PG pin\n");
> > +			return PTR_ERR(bq->pg);
> > +		}
> > +	} else {
> > +		if (!gpio_is_valid(pdata->pg_gpio)) {
> > +			dev_info(bq->dev, "invalid PG pin\n");
> > +			return -EINVAL;
> > +		}
> > +
> > +		ret = devm_gpio_request_one(bq->dev, pdata->pg_gpio,
> > +					    GPIOD_IN, BQ24257_PG_GPIO);
> 
> ditto

OK.
 
> > +		if (ret) {
> > +			dev_info(bq->dev, "PG pin request failed\n");
> > +			return ret;
> > +		}
> > +
> > +		bq->pg = gpio_to_desc(pdata->pg_gpio);
> > +		if (!bq->pg) {
> > +			dev_info(bq->dev, "could not get PG pin descriptor\n");
> > +			return -EINVAL;
> > +		}
> >  	}
> >  
> > +	dev_dbg(bq->dev, "probed PG pin = %d", desc_to_gpio(bq->pg));
> > +
> >  	return 0;
> >  }
> >  
> > +static void bq24257_pdata_probe(struct bq24257_device *bq,
> > +				struct bq24257_platform_data *pdata)
> > +{
> > +	bq->init_data.ichg = bq24257_find_idx(pdata->ichg,
> > +					      bq24257_ichg_map,
> > +					      BQ24257_ICHG_MAP_SIZE);
> > +
> > +	bq->init_data.vbat = bq24257_find_idx(pdata->vbat,
> > +					      bq24257_vbat_map,
> > +					      BQ24257_VBAT_MAP_SIZE);
> > +
> > +	bq->init_data.iterm = bq24257_find_idx(pdata->iterm,
> > +					       bq24257_iterm_map,
> > +					       BQ24257_ITERM_MAP_SIZE);
> > +
> > +	bq->init_data.in_ilimit = bq24257_find_idx(pdata->in_ilimit,
> > +						   bq24257_iilimit_map,
> > +						   BQ24257_IILIMIT_MAP_SIZE);
> > +
> > +	bq->init_data.vovp = bq24257_find_idx(pdata->vovp,
> > +					      bq24257_vovp_map,
> > +					      BQ24257_VOVP_MAP_SIZE);
> > +
> > +	bq->init_data.vindpm = bq24257_find_idx(pdata->vindpm,
> > +						bq24257_vindpm_map,
> > +						BQ24257_VINDPM_MAP_SIZE);
> > +
> > +	bq->in_ilimit_autoset_disable = pdata->in_ilimit_autoset_disable;
> > +
> > +	bq->pg_gpio_disable = pdata->pg_gpio_disable;
> > +}
> > +
> >  static int bq24257_fw_probe(struct bq24257_device *bq)
> >  {
> >  	int ret;
> > @@ -974,6 +1061,7 @@ static int bq24257_probe(struct i2c_client *client,
> >  	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
> >  	struct device *dev = &client->dev;
> >  	const struct acpi_device_id *acpi_id;
> > +	struct bq24257_platform_data *pdata = client->dev.platform_data;
> >  	struct bq24257_device *bq;
> >  	int ret;
> >  	int i;
> > @@ -1023,14 +1111,15 @@ static int bq24257_probe(struct i2c_client *client,
> >  
> >  	i2c_set_clientdata(client, bq);
> >  
> > -	if (!dev->platform_data) {
> > +	if (!pdata) {
> >  		ret = bq24257_fw_probe(bq);
> >  		if (ret < 0) {
> >  			dev_err(dev, "Cannot read device properties.\n");
> >  			return ret;
> >  		}
> >  	} else {
> > -		return -ENODEV;
> > +		dev_dbg(dev, "init using platform data\n");
> > +		bq24257_pdata_probe(bq, pdata);
> >  	}
> >  
> >  	/*
> > @@ -1087,7 +1176,13 @@ static int bq24257_probe(struct i2c_client *client,
> >  		return ret;
> >  	}
> >  
> > -	if (client->irq <= 0)
> > +	/*
> > +	 * When using device firmware we either take the IRQ specified directly
> > +	 * or probe for a pin named BQ24257_STAT_IRQ. In case of using platform
> > +	 * data always run the IRQ pin probe function to finish IRQ and GPIO
> > +	 * setup based on the stat pin specified in the platform data.
> > +	 */
> 
> Why?

The original driver would allow configuring the IRQ either through
client->irq or through a separete DT entry called "stat_gpios" (which
seems redundant... might it be required for ACPI? Or...?). I modeled the
configuration via pdata the same way, this way aligning the fields in
the pdata structure with the DT entries. Let me know if you have a
preference to simplify this.

> 
> > +	if (client->irq <= 0 || pdata)
> >  		client->irq = bq24257_irq_probe(bq);
> >  
> >  	if (client->irq < 0) {
> > diff --git a/include/linux/power/bq24257_charger.h b/include/linux/power/bq24257_charger.h
> > new file mode 100644
> > index 0000000..d4f3703
> > --- /dev/null
> > +++ b/include/linux/power/bq24257_charger.h
> > @@ -0,0 +1,29 @@
> > +/*
> > + * Platform data for the TI bq24257 battery charger driver.
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License version 2 as
> > + * published by the Free Software Foundation.
> > + */
> > +
> > +#ifndef _BQ24257_CHARGER_H_
> > +#define _BQ24257_CHARGER_H_
> > +
> > +#include <asm/types.h>
> > +#include <linux/types.h>
> > +
> > +struct bq24257_platform_data {
> > +	u32 ichg;				       /* charge current (uA) */
> > +	u32 vbat;				   /* regulation voltage (uV) */
> > +	u32 iterm;				  /* termination current (uA) */
> > +	u32 in_ilimit;				  /* input current limit (uA) */
> > +	u32 vovp;		      /* over voltage protection voltage (uV) */
> > +	u32 vindpm;			 /* VDMP input threshold voltage (uV) */
> > +	bool in_ilimit_autoset_disable;	/* auto-detect of input current limit */
> > +	bool pg_gpio_disable;	     /* use of a dedicated pin for Power Good */
> > +
> > +	int stat_gpio;				  /* stat_int (interrupt) pin */
> > +	int pg_gpio;					    /* power good pin */
> > +};
> > +
> > +#endif
> 
> #endif /* _BQ24257_CHARGER_H_ */

Ok.

Regards,

--
Andreas Dannenberg
Texas Instruments Inc

> 
> Best regards,
> Krzysztof
>