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>
Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index b5aa50c5163358e5938e0858fb4c024410b7c95c..1dabd1d79c1d1f9ca444b993e7a6fb8f7fb9da11 100644 (file)
--- 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 2a57d024481db8c354badd976843f83a365c72a9..d957c4bbc8c1840a152a7e841cd4fe6b0c39f808 100644 (file)
--- 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);