[PATCHv3,02/14] pinctrl: mcp23s08: add pinconf support

mcp23xxx device have configurable 100k pullup resistors. This adds
support for enabling them using pinctrl's pinconf interface.

Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
---
 drivers/pinctrl/Kconfig            |   1 +
 drivers/pinctrl/pinctrl-mcp23s08.c | 199 ++++++++++++++++++++++++++++++++-----
 2 files changed, 176 insertions(+), 24 deletions(-)

Hi,

On Mon, May 15, 2017 at 11:24:26AM +0200, Sebastian Reichel wrote:
> mcp23xxx device have configurable 100k pullup resistors. This adds
> support for enabling them using pinctrl's pinconf interface.
> 
> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>

I just noticed, that I forgot to add:

Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

-- Sebastian

> ---
>  drivers/pinctrl/Kconfig            |   1 +
>  drivers/pinctrl/pinctrl-mcp23s08.c | 199 ++++++++++++++++++++++++++++++++-----
>  2 files changed, 176 insertions(+), 24 deletions(-)
> 
> diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
> index b5aa50c51633..1dabd1d79c1d 100644
> --- a/drivers/pinctrl/Kconfig
> +++ b/drivers/pinctrl/Kconfig
> @@ -153,6 +153,7 @@ config PINCTRL_MCP23S08
>  	select GPIOLIB_IRQCHIP
>  	select REGMAP_I2C if I2C
>  	select REGMAP_SPI if SPI_MASTER
> +	select GENERIC_PINCONF
>  	help
>  	  SPI/I2C driver for Microchip MCP23S08/MCP23S17/MCP23008/MCP23017
>  	  I/O expanders.
> diff --git a/drivers/pinctrl/pinctrl-mcp23s08.c b/drivers/pinctrl/pinctrl-mcp23s08.c
> index 2a57d024481d..d957c4bbc8c1 100644
> --- a/drivers/pinctrl/pinctrl-mcp23s08.c
> +++ b/drivers/pinctrl/pinctrl-mcp23s08.c
> @@ -24,6 +24,9 @@
>  #include <linux/of_irq.h>
>  #include <linux/of_device.h>
>  #include <linux/regmap.h>
> +#include <linux/pinctrl/pinctrl.h>
> +#include <linux/pinctrl/pinconf.h>
> +#include <linux/pinctrl/pinconf-generic.h>
>  
>  /**
>   * MCP types supported by driver
> @@ -77,6 +80,9 @@ struct mcp23s08 {
>  
>  	struct regmap		*regmap;
>  	struct device		*dev;
> +
> +	struct pinctrl_dev	*pctldev;
> +	struct pinctrl_desc	pinctrl_desc;
>  };
>  
>  static const struct regmap_config mcp23x08_regmap = {
> @@ -96,6 +102,158 @@ static const struct regmap_config mcp23x17_regmap = {
>  	.val_format_endian = REGMAP_ENDIAN_LITTLE,
>  };
>  
> +static int mcp_read(struct mcp23s08 *mcp, unsigned int reg, unsigned int *val)
> +{
> +	return regmap_read(mcp->regmap, reg << mcp->reg_shift, val);
> +}
> +
> +static int mcp_write(struct mcp23s08 *mcp, unsigned int reg, unsigned int val)
> +{
> +	return regmap_write(mcp->regmap, reg << mcp->reg_shift, val);
> +}
> +
> +static int mcp_set_bit(struct mcp23s08 *mcp, unsigned int reg,
> +		       unsigned int pin, bool enabled)
> +{
> +	u16 val  = enabled ? 0xffff : 0x0000;
> +	u16 mask = BIT(pin);
> +	return regmap_update_bits(mcp->regmap, reg << mcp->reg_shift,
> +				  mask, val);
> +}
> +
> +static int mcp_update_cache(struct mcp23s08 *mcp)
> +{
> +	int ret, reg, i;
> +
> +	for (i = 0; i < ARRAY_SIZE(mcp->cache); i++) {
> +		ret = mcp_read(mcp, i, &reg);
> +		if (ret < 0)
> +			return ret;
> +		mcp->cache[i] = reg;
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct pinctrl_pin_desc mcp23x08_pins[] = {
> +	PINCTRL_PIN(0, "gpio0"),
> +	PINCTRL_PIN(1, "gpio1"),
> +	PINCTRL_PIN(2, "gpio2"),
> +	PINCTRL_PIN(3, "gpio3"),
> +	PINCTRL_PIN(4, "gpio4"),
> +	PINCTRL_PIN(5, "gpio5"),
> +	PINCTRL_PIN(6, "gpio6"),
> +	PINCTRL_PIN(7, "gpio7"),
> +};
> +
> +static const struct pinctrl_pin_desc mcp23x17_pins[] = {
> +	PINCTRL_PIN(0, "gpio0"),
> +	PINCTRL_PIN(1, "gpio1"),
> +	PINCTRL_PIN(2, "gpio2"),
> +	PINCTRL_PIN(3, "gpio3"),
> +	PINCTRL_PIN(4, "gpio4"),
> +	PINCTRL_PIN(5, "gpio5"),
> +	PINCTRL_PIN(6, "gpio6"),
> +	PINCTRL_PIN(7, "gpio7"),
> +	PINCTRL_PIN(8, "gpio8"),
> +	PINCTRL_PIN(9, "gpio9"),
> +	PINCTRL_PIN(10, "gpio10"),
> +	PINCTRL_PIN(11, "gpio11"),
> +	PINCTRL_PIN(12, "gpio12"),
> +	PINCTRL_PIN(13, "gpio13"),
> +	PINCTRL_PIN(14, "gpio14"),
> +	PINCTRL_PIN(15, "gpio15"),
> +};
> +
> +static int mcp_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
> +{
> +	return 0;
> +}
> +
> +static const char *mcp_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
> +						unsigned int group)
> +{
> +	return NULL;
> +}
> +
> +static int mcp_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
> +					unsigned int group,
> +					const unsigned int **pins,
> +					unsigned int *num_pins)
> +{
> +	return -ENOTSUPP;
> +}
> +
> +static const struct pinctrl_ops mcp_pinctrl_ops = {
> +	.get_groups_count = mcp_pinctrl_get_groups_count,
> +	.get_group_name = mcp_pinctrl_get_group_name,
> +	.get_group_pins = mcp_pinctrl_get_group_pins,
> +#ifdef CONFIG_OF
> +	.dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
> +	.dt_free_map = pinconf_generic_dt_free_map,
> +#endif
> +};
> +
> +static int mcp_pinconf_get(struct pinctrl_dev *pctldev, unsigned int pin,
> +			      unsigned long *config)
> +{
> +	struct mcp23s08 *mcp = pinctrl_dev_get_drvdata(pctldev);
> +	enum pin_config_param param = pinconf_to_config_param(*config);
> +	unsigned int data, status;
> +	int ret;
> +
> +	switch (param) {
> +	case PIN_CONFIG_BIAS_PULL_UP:
> +		ret = mcp_read(mcp, MCP_GPPU, &data);
> +		if (ret < 0)
> +			return ret;
> +		status = (data & BIT(pin)) ? 1 : 0;
> +		break;
> +	default:
> +		dev_err(mcp->dev, "Invalid config param %04x\n", param);
> +		return -ENOTSUPP;
> +	}
> +
> +	*config = 0;
> +
> +	return status ? 0 : -EINVAL;
> +}
> +
> +static int mcp_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
> +			      unsigned long *configs, unsigned int num_configs)
> +{
> +	struct mcp23s08 *mcp = pinctrl_dev_get_drvdata(pctldev);
> +	enum pin_config_param param;
> +	u32 arg, mask;
> +	u16 val;
> +	int ret = 0;
> +	int i;
> +
> +	for (i = 0; i < num_configs; i++) {
> +		param = pinconf_to_config_param(configs[i]);
> +		arg = pinconf_to_config_argument(configs[i]);
> +
> +		switch (param) {
> +		case PIN_CONFIG_BIAS_PULL_UP:
> +			val = arg ? 0xFFFF : 0x0000;
> +			mask = BIT(pin);
> +			ret = mcp_set_bit(mcp, MCP_GPPU, pin, arg);
> +			break;
> +		default:
> +			dev_err(mcp->dev, "Invalid config param %04x\n", param);
> +			return -ENOTSUPP;
> +		}
> +	}
> +
> +	return ret;
> +}
> +
> +static const struct pinconf_ops mcp_pinconf_ops = {
> +	.pin_config_get = mcp_pinconf_get,
> +	.pin_config_set = mcp_pinconf_set,
> +	.is_generic = true,
> +};
> +
>  /*----------------------------------------------------------------------*/
>  
>  #ifdef CONFIG_SPI_MASTER
> @@ -158,30 +316,6 @@ static const struct regmap_bus mcp23sxx_spi_regmap = {
>  
>  #endif /* CONFIG_SPI_MASTER */
>  
> -static int mcp_read(struct mcp23s08 *mcp, unsigned int reg, unsigned int *val)
> -{
> -	return regmap_read(mcp->regmap, reg << mcp->reg_shift, val);
> -}
> -
> -static int mcp_write(struct mcp23s08 *mcp, unsigned int reg, unsigned int val)
> -{
> -	return regmap_write(mcp->regmap, reg << mcp->reg_shift, val);
> -}
> -
> -static int mcp_update_cache(struct mcp23s08 *mcp)
> -{
> -	int ret, reg, i;
> -
> -	for (i = 0; i < ARRAY_SIZE(mcp->cache); i++) {
> -		ret = mcp_read(mcp, i, &reg);
> -		if (ret < 0)
> -			return ret;
> -		mcp->cache[i] = reg;
> -	}
> -
> -	return 0;
> -}
> -
>  /*----------------------------------------------------------------------*/
>  
>  /* A given spi_device can represent up to eight mcp23sxx chips
> @@ -682,6 +816,23 @@ static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
>  		if (ret)
>  			goto fail;
>  	}
> +
> +	mcp->pinctrl_desc.name = "mcp23xxx-pinctrl";
> +	mcp->pinctrl_desc.pctlops = &mcp_pinctrl_ops;
> +	mcp->pinctrl_desc.confops = &mcp_pinconf_ops;
> +	mcp->pinctrl_desc.npins = mcp->chip.ngpio;
> +	if (mcp->pinctrl_desc.npins == 8)
> +		mcp->pinctrl_desc.pins = mcp23x08_pins;
> +	else if (mcp->pinctrl_desc.npins == 16)
> +		mcp->pinctrl_desc.pins = mcp23x17_pins;
> +	mcp->pinctrl_desc.owner = THIS_MODULE;
> +
> +	mcp->pctldev = devm_pinctrl_register(dev, &mcp->pinctrl_desc, mcp);
> +	if (IS_ERR(mcp->pctldev)) {
> +		ret = PTR_ERR(mcp->pctldev);
> +		goto fail;
> +	}
> +
>  fail:
>  	if (ret < 0)
>  		dev_dbg(dev, "can't setup chip %d, --> %d\n", addr, ret);
> -- 
> 2.11.0
>