[PATCH v9 2/3] gpio: lp873x: Add support for General Purpose Outputs

Keerthy
2016-08-31T08:59:34Z

Add driver for lp873x PMIC family GPOs. Two GPOs are supported
and can be configured in Open-drain output or Push-pull output.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Keerthy <j-keerthy@ti.com>
---
drivers/gpio/Kconfig | 10 +++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-lp873x.c | 193 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 204 insertions(+)
create mode 100644 drivers/gpio/gpio-lp873x.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 30c5373..c489f50 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -880,6 +880,16 @@ config GPIO_LP3943
LP3943 can be used as a GPIO expander which provides up to 16 GPIOs.
Open drain outputs are required for this usage.

+config GPIO_LP873X
+ tristate "TI LP873X GPO"
+ depends on MFD_TI_LP873X
+ help
+ This driver supports the GPO on TI Lp873x PMICs. 2 GPOs are present
+ on LP873X PMICs.
+
+ This driver can also be built as a module. If so, the module will be
+ called gpio-lp873x.
+
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 691fb3a..b313fee 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -58,6 +58,7 @@ obj-$(CONFIG_GPIO_LOONGSON) += gpio-loongson.o
obj-$(CONFIG_GPIO_LP3943) += gpio-lp3943.o
obj-$(CONFIG_GPIO_LPC18XX) += gpio-lpc18xx.o
obj-$(CONFIG_ARCH_LPC32XX) += gpio-lpc32xx.o
+obj-$(CONFIG_GPIO_LP873X) += gpio-lp873x.o
obj-$(CONFIG_GPIO_LYNXPOINT) += gpio-lynxpoint.o
obj-$(CONFIG_GPIO_MAX730X) += gpio-max730x.o
obj-$(CONFIG_GPIO_MAX7300) += gpio-max7300.o
diff --git a/drivers/gpio/gpio-lp873x.c b/drivers/gpio/gpio-lp873x.c
new file mode 100644
index 0000000..f10d49d
--- /dev/null
+++ b/drivers/gpio/gpio-lp873x.c
@@ -0,0 +1,193 @@
+/*
+ * Copyright (C) 2016 Texas Instruments Incorporated - http://www.ti.com/
+ * Keerthy <j-keerthy@ti.com>
+ *
+ * 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.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether expressed or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License version 2 for more details.
+ *
+ * Based on the TPS65218 driver
+ */
+
+#include <linux/gpio.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include <linux/mfd/lp873x.h>
+
+#define BITS_PER_GPO 0x4
+#define LP873X_GPO_CTRL_OD 0x2
+
+struct lp873x_gpio {
+ struct gpio_chip chip;
+ struct lp873x *lp873;
+};
+
+static int lp873x_gpio_get_direction(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ /* This device is output only */
+ return 0;
+}
+
+static int lp873x_gpio_direction_input(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ /* This device is output only */
+ return -EINVAL;
+}
+
+static int lp873x_gpio_direction_output(struct gpio_chip *chip,
+ unsigned int offset, int value)
+{
+ struct lp873x_gpio *gpio = gpiochip_get_data(chip);
+
+ /* Set the initial value */
+ return regmap_update_bits(gpio->lp873->regmap, LP873X_REG_GPO_CTRL,
+ BIT(offset * BITS_PER_GPO),
+ value ? BIT(offset * BITS_PER_GPO) : 0);
+}
+
+static int lp873x_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+ struct lp873x_gpio *gpio = gpiochip_get_data(chip);
+ int ret, val;
+
+ ret = regmap_read(gpio->lp873->regmap, LP873X_REG_GPO_CTRL, &val);
+ if (ret < 0)
+ return ret;
+
+ return val & BIT(offset * BITS_PER_GPO);
+}
+
+static void lp873x_gpio_set(struct gpio_chip *chip, unsigned int offset,
+ int value)
+{
+ struct lp873x_gpio *gpio = gpiochip_get_data(chip);
+
+ regmap_update_bits(gpio->lp873->regmap, LP873X_REG_GPO_CTRL,
+ BIT(offset * BITS_PER_GPO),
+ value ? BIT(offset * BITS_PER_GPO) : 0);
+}
+
+static int lp873x_gpio_request(struct gpio_chip *gc, unsigned int offset)
+{
+ struct lp873x_gpio *gpio = gpiochip_get_data(gc);
+ int ret;
+
+ switch (offset) {
+ case 0:
+ /* No MUX Set up Needed for GPO */
+ break;
+ case 1:
+ /* Setup the CLKIN_PIN_SEL MUX to GPO2 */
+ ret = regmap_update_bits(gpio->lp873->regmap, LP873X_REG_CONFIG,
+ LP873X_CONFIG_CLKIN_PIN_SEL, 0);
+ if (ret)
+ return ret;
+
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int lp873x_gpio_set_single_ended(struct gpio_chip *gc,
+ unsigned int offset,
+ enum single_ended_mode mode)
+{
+ struct lp873x_gpio *gpio = gpiochip_get_data(gc);
+
+ switch (mode) {
+ case LINE_MODE_OPEN_DRAIN:
+ return regmap_update_bits(gpio->lp873->regmap,
+ LP873X_REG_GPO_CTRL,
+ BIT(offset * BITS_PER_GPO +
+ LP873X_GPO_CTRL_OD),
+ BIT(offset * BITS_PER_GPO +
+ LP873X_GPO_CTRL_OD));
+ case LINE_MODE_PUSH_PULL:
+ return regmap_update_bits(gpio->lp873->regmap,
+ LP873X_REG_GPO_CTRL,
+ BIT(offset * BITS_PER_GPO +
+ LP873X_GPO_CTRL_OD), 0);
+ default:
+ return -ENOTSUPP;
+ }
+}
+
+static struct gpio_chip template_chip = {
+ .label = "lp873x-gpio",
+ .owner = THIS_MODULE,
+ .request = lp873x_gpio_request,
+ .get_direction = lp873x_gpio_get_direction,
+ .direction_input = lp873x_gpio_direction_input,
+ .direction_output = lp873x_gpio_direction_output,
+ .get = lp873x_gpio_get,
+ .set = lp873x_gpio_set,
+ .set_single_ended = lp873x_gpio_set_single_ended,
+ .base = -1,
+ .ngpio = 2,
+ .can_sleep = true,
+};
+
+static int lp873x_gpio_probe(struct platform_device *pdev)
+{
+ struct lp873x_gpio *gpio;
+ int ret;
+
+ gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
+ if (!gpio)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, gpio);
+
+ gpio->lp873 = dev_get_drvdata(pdev->dev.parent);
+ gpio->chip = template_chip;
+ gpio->chip.parent = gpio->lp873->dev;
+
+ ret = gpiochip_add_data(&gpio->chip, gpio);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int lp873x_gpio_remove(struct platform_device *pdev)
+{
+ struct lp873x_gpio *gpio = platform_get_drvdata(pdev);
+
+ gpiochip_remove(&gpio->chip);
+
+ return 0;
+}
+
+static const struct platform_device_id lp873x_gpio_id_table[] = {
+ { "lp873x-gpio", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(platform, lp873x_gpio_id_table);
+
+static struct platform_driver lp873x_gpio_driver = {
+ .driver = {
+ .name = "lp873x-gpio",
+ },
+ .probe = lp873x_gpio_probe,
+ .remove = lp873x_gpio_remove,
+ .id_table = lp873x_gpio_id_table,
+};
+module_platform_driver(lp873x_gpio_driver);
+
+MODULE_AUTHOR("Keerthy <j-keerthy@ti.com>");
+MODULE_DESCRIPTION("LP873X GPIO driver");
+MODULE_LICENSE("GPL v2");
--
1.9.1