gpio: madera: Support Cirrus Logic Madera class codecs

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.

Change-Id: Id3473e03a0d0b3eea908d35f0ca2761bead3fb73
Signed-off-by: Nariman Poushin <nariman@opensource.wolfsonmicro.com>
Signed-off-by: Richard Fitzgerald <rf@opensource.wolfsonmicro.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>

diff --git a/MAINTAINERS b/MAINTAINERS
index e4209dcde92da474c945a6ca8fb57ef06dedcb93..e6942d51a070fb4dc45332aad9e597cb9eeafbda 100644 (file)
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3399,10 +3399,12 @@ L:      patches@opensource.wolfsonmicro.com
 T:     git https://github.com/CirrusLogic/linux-drivers.git
 W:     https://github.com/CirrusLogic/linux-drivers/wiki
 S:     Supported
+F:     Documentation/devicetree/bindings/gpio/gpio-madera.txt
 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 3f80f167ed56d917405aaad1dd5e09598c7fc9e6..687f7bfd988947ec03d3592aa91d26f54848fd52 100644 (file)
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -986,6 +986,12 @@ 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 8a2dfba3b2310ef2e25c0a1086a12c60a53ecda2..56727c74b6f41fbc98dfe38f2be9baff303e35ff 100644 (file)
--- 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_MAX730X)     += gpio-max730x.o
 obj-$(CONFIG_GPIO_MAX7300)     += gpio-max7300.o
 obj-$(CONFIG_GPIO_MAX7301)     += gpio-max7301.o

diff --git a/drivers/gpio/gpio-madera.c b/drivers/gpio/gpio-madera.c
new file mode 100644 (file)
index 0000000..d700e93
--- /dev/null
+++ b/drivers/gpio/gpio-madera.c
@@ -0,0 +1,186 @@
+/*
+ * 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,
+       .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,
+       .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;
+       }
+
+       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 <nariman@opensource.wolfsonmicro.com>");
+MODULE_AUTHOR("Richard Fitzgerald <rf@opensource.wolfsonmicro.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:madera-gpio");