This adds support for the GPIOs on Cirrus Logic Madera class codecs.
Any pins not used for special functions (see the pinctrl driver) can be
used as general single-bit input or output lines. The number of available
GPIOs varies between codecs.

Signed-off-by: Nariman Poushin <nari...@opensource.wolfsonmicro.com>
Signed-off-by: Richard Fitzgerald <r...@opensource.wolfsonmicro.com>
Signed-off-by: Charles Keepax <ckee...@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.wall...@linaro.org>
---
 MAINTAINERS                |   1 +
 drivers/gpio/Kconfig       |   6 ++
 drivers/gpio/Makefile      |   1 +
 drivers/gpio/gpio-madera.c | 196 +++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 204 insertions(+)
 create mode 100644 drivers/gpio/gpio-madera.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 2c6772f81d88..7f3f2de4cc44 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3490,6 +3490,7 @@ F:        Documentation/devicetree/bindings/mfd/madera.txt
 F:     Documentation/devicetree/bindings/pinctrl/cirrus,madera-pinctrl.txt
 F:     include/linux/irqchip/irq-madera*
 F:     include/linux/mfd/madera/*
+F:     drivers/gpio/gpio-madera*
 F:     drivers/irqchip/irq-madera*
 F:     drivers/mfd/madera*
 F:     drivers/mfd/cs47l*
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index d6a8e851ad13..95e4bbcf9bf7 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -993,6 +993,12 @@ config GPIO_LP87565
          This driver can also be built as a module. If so, the module will be
          called gpio-lp87565.
 
+config GPIO_MADERA
+       bool "Cirrus Logic Madera class codecs"
+       depends on PINCTRL_MADERA
+       help
+         Support for GPIOs on Cirrus Logic Madera class codecs.
+
 config GPIO_MAX77620
        tristate "GPIO support for PMIC MAX77620 and MAX20024"
        depends on MFD_MAX77620
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 4bc24febb889..765125eb7d4c 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -70,6 +70,7 @@ obj-$(CONFIG_ARCH_LPC32XX)    += gpio-lpc32xx.o
 obj-$(CONFIG_GPIO_LP873X)      += gpio-lp873x.o
 obj-$(CONFIG_GPIO_LP87565)     += gpio-lp87565.o
 obj-$(CONFIG_GPIO_LYNXPOINT)   += gpio-lynxpoint.o
+obj-$(CONFIG_GPIO_MADERA)      += gpio-madera.o
 obj-$(CONFIG_GPIO_MAX3191X)    += gpio-max3191x.o
 obj-$(CONFIG_GPIO_MAX730X)     += gpio-max730x.o
 obj-$(CONFIG_GPIO_MAX7300)     += gpio-max7300.o
diff --git a/drivers/gpio/gpio-madera.c b/drivers/gpio/gpio-madera.c
new file mode 100644
index 000000000000..e45905d59238
--- /dev/null
+++ b/drivers/gpio/gpio-madera.c
@@ -0,0 +1,196 @@
+/*
+ * GPIO support for Cirrus Logic Madera codecs
+ *
+ * Copyright 2015-2017 Cirrus Logic
+ *
+ * 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.
+ */
+
+#include <linux/device.h>
+#include <linux/gpio.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include <linux/mfd/madera/core.h>
+#include <linux/mfd/madera/pdata.h>
+#include <linux/mfd/madera/registers.h>
+
+struct madera_gpio {
+       struct madera *madera;
+       struct gpio_chip gpio_chip;
+};
+
+static int madera_gpio_get_direction(struct gpio_chip *chip,
+                                    unsigned int offset)
+{
+       struct madera_gpio *madera_gpio = gpiochip_get_data(chip);
+       struct madera *madera = madera_gpio->madera;
+       unsigned int val;
+       int ret;
+
+       ret = regmap_read(madera->regmap,
+                         MADERA_GPIO1_CTRL_2 + (2 * offset), &val);
+       if (ret < 0)
+               return ret;
+
+       return (val & MADERA_GP1_DIR_MASK) >> MADERA_GP1_DIR_SHIFT;
+}
+
+static int madera_gpio_direction_in(struct gpio_chip *chip, unsigned int 
offset)
+{
+       struct madera_gpio *madera_gpio = gpiochip_get_data(chip);
+       struct madera *madera = madera_gpio->madera;
+
+       return regmap_update_bits(madera->regmap,
+                                 MADERA_GPIO1_CTRL_2 + (2 * offset),
+                                 MADERA_GP1_DIR_MASK, MADERA_GP1_DIR);
+}
+
+static int madera_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+       struct madera_gpio *madera_gpio = gpiochip_get_data(chip);
+       struct madera *madera = madera_gpio->madera;
+       unsigned int val;
+       int ret;
+
+       ret = regmap_read(madera->regmap,
+                         MADERA_GPIO1_CTRL_1 + (2 * offset), &val);
+       if (ret < 0)
+               return ret;
+
+       return !!(val & MADERA_GP1_LVL_MASK);
+}
+
+static int madera_gpio_direction_out(struct gpio_chip *chip,
+                                    unsigned int offset, int value)
+{
+       struct madera_gpio *madera_gpio = gpiochip_get_data(chip);
+       struct madera *madera = madera_gpio->madera;
+       unsigned int regval;
+       int ret;
+
+       if (value)
+               regval = MADERA_GP1_LVL;
+       else
+               regval = 0;
+
+       ret = regmap_update_bits(madera->regmap,
+                                MADERA_GPIO1_CTRL_2 + (2 * offset),
+                                MADERA_GP1_DIR_MASK, 0);
+       if (ret < 0)
+               return ret;
+
+       return regmap_update_bits(madera->regmap,
+                                 MADERA_GPIO1_CTRL_1 + (2 * offset),
+                                 MADERA_GP1_LVL_MASK, regval);
+}
+
+static void madera_gpio_set(struct gpio_chip *chip, unsigned int offset,
+                           int value)
+{
+       struct madera_gpio *madera_gpio = gpiochip_get_data(chip);
+       struct madera *madera = madera_gpio->madera;
+       unsigned int regval;
+       int ret;
+
+       if (value)
+               regval = MADERA_GP1_LVL;
+       else
+               regval = 0;
+
+       ret = regmap_update_bits(madera->regmap,
+                                MADERA_GPIO1_CTRL_1 + (2 * offset),
+                                MADERA_GP1_LVL_MASK, regval);
+       if (ret)
+               dev_warn(madera->dev, "Failed to write to 0x%x (%d)\n",
+                        MADERA_GPIO1_CTRL_1 + (2 * offset), ret);
+}
+
+static struct gpio_chip template_chip = {
+       .label                  = "madera",
+       .owner                  = THIS_MODULE,
+       .request                = gpiochip_generic_request,
+       .free                   = gpiochip_generic_free,
+       .get_direction          = madera_gpio_get_direction,
+       .direction_input        = madera_gpio_direction_in,
+       .get                    = madera_gpio_get,
+       .direction_output       = madera_gpio_direction_out,
+       .set                    = madera_gpio_set,
+       .set_config             = gpiochip_generic_config,
+       .can_sleep              = true,
+};
+
+static int madera_gpio_probe(struct platform_device *pdev)
+{
+       struct madera *madera = dev_get_drvdata(pdev->dev.parent);
+       struct madera_pdata *pdata = dev_get_platdata(madera->dev);
+       struct madera_gpio *madera_gpio;
+       int ret;
+
+       madera_gpio = devm_kzalloc(&pdev->dev, sizeof(*madera_gpio),
+                                  GFP_KERNEL);
+       if (!madera_gpio)
+               return -ENOMEM;
+
+       madera_gpio->madera = madera;
+       madera_gpio->gpio_chip = template_chip;
+       madera_gpio->gpio_chip.parent = &pdev->dev;
+
+       if (IS_ENABLED(CONFIG_OF_GPIO))
+               madera_gpio->gpio_chip.of_node = madera->dev->of_node;
+
+       switch (madera->type) {
+       case CS47L35:
+               madera_gpio->gpio_chip.ngpio = CS47L35_NUM_GPIOS;
+               break;
+       case CS47L85:
+       case WM1840:
+               madera_gpio->gpio_chip.ngpio = CS47L85_NUM_GPIOS;
+               break;
+       case CS47L90:
+       case CS47L91:
+               madera_gpio->gpio_chip.ngpio = CS47L90_NUM_GPIOS;
+               break;
+       default:
+               dev_err(&pdev->dev, "Unknown chip variant %d\n", madera->type);
+               return -EINVAL;
+       }
+
+       if (pdata && pdata->gpio_base)
+               madera_gpio->gpio_chip.base = pdata->gpio_base;
+       else
+               madera_gpio->gpio_chip.base = -1;
+
+       ret = devm_gpiochip_add_data(&pdev->dev, &madera_gpio->gpio_chip,
+                                    madera_gpio);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
+               return ret;
+       }
+
+       ret = gpiochip_add_pin_range(&madera_gpio->gpio_chip, "madera-pinctrl",
+                                    0, 0, madera_gpio->gpio_chip.ngpio);
+       if (ret) {
+               dev_warn(&pdev->dev, "Failed to add pin range (%d)\n", ret);
+               return ret;
+       }
+
+       return 0;
+}
+
+static struct platform_driver madera_gpio_driver = {
+       .driver.name    = "madera-gpio",
+       .driver.owner   = THIS_MODULE,
+       .probe          = madera_gpio_probe,
+};
+
+module_platform_driver(madera_gpio_driver);
+
+MODULE_DESCRIPTION("GPIO interface for Madera codecs");
+MODULE_AUTHOR("Nariman Poushin <nari...@opensource.wolfsonmicro.com>");
+MODULE_AUTHOR("Richard Fitzgerald <r...@opensource.wolfsonmicro.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:madera-gpio");
-- 
2.11.0

Reply via email to