ar71xx: add GPIO driver for the NXP 74HC153 chip

SVN-Revision: 19149

2 files changed, 270 insertions, 0 deletions

diff --git a/target/linux/ar71xx/files/drivers/gpio/nxp_74hc153.c b/target/linux/ar71xx/files/drivers/gpio/nxp_74hc153.c
new file mode 100644
index 0000000..b4f1662
--- /dev/null
+++ b/target/linux/ar71xx/files/drivers/gpio/nxp_74hc153.c
@@ -0,0 +1,246 @@
+/*
+ *  NXP 74HC153 - Dual 4-input multiplexer GPIO driver
+ *
+ *  Copyright (C) 2010 Gabor Juhos <juhosg@openwrt.org>
+ *
+ *  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/module.h>
+#include <linux/init.h>
+#include <linux/gpio.h>
+#include <linux/platform_device.h>
+#include <linux/nxp_74hc153.h>
+
+#define NXP_74HC153_NUM_GPIOS	8
+#define NXP_74HC153_S0_MASK	0x1
+#define NXP_74HC153_S1_MASK	0x2
+#define NXP_74HC153_BANK_MASK	0x4
+
+struct nxp_74hc153_chip {
+	struct device		*parent;
+	struct gpio_chip	gpio_chip;
+	struct mutex		lock;
+};
+
+static struct nxp_74hc153_chip *gpio_to_nxp(struct gpio_chip *gc)
+{
+	return container_of(gc, struct nxp_74hc153_chip, gpio_chip);
+}
+
+static int nxp_74hc153_direction_input(struct gpio_chip *gc, unsigned offset)
+{
+	return 0;
+}
+
+static int nxp_74hc153_direction_output(struct gpio_chip *gc,
+					unsigned offset, int val)
+{
+	return -EINVAL;
+}
+
+static int nxp_74hc153_get_value(struct gpio_chip *gc, unsigned offset)
+{
+	struct nxp_74hc153_chip *nxp;
+	struct nxp_74hc153_platform_data *pdata;
+	unsigned s0;
+	unsigned s1;
+	unsigned pin;
+	int ret;
+
+	nxp = gpio_to_nxp(gc);
+	pdata = nxp->parent->platform_data;
+
+	s0 = !!(offset & NXP_74HC153_S0_MASK);
+	s1 = !!(offset & NXP_74HC153_S1_MASK);
+	pin = (offset & NXP_74HC153_BANK_MASK) ? pdata->gpio_pin_2y
+					       : pdata->gpio_pin_1y;
+
+	mutex_lock(&nxp->lock);
+	gpio_set_value(pdata->gpio_pin_s0, s0);
+	gpio_set_value(pdata->gpio_pin_s1, s1);
+	ret = gpio_get_value(pin);
+	mutex_unlock(&nxp->lock);
+
+	return ret;
+}
+
+static void nxp_74hc153_set_value(struct gpio_chip *gc,
+				  unsigned offset, int val)
+{
+	/* not supported */
+}
+
+static int __devinit nxp_74hc153_probe(struct platform_device *pdev)
+{
+	struct nxp_74hc153_platform_data *pdata;
+	struct nxp_74hc153_chip *nxp;
+	struct gpio_chip *gc;
+	int err;
+
+	pdata = pdev->dev.platform_data;
+	if (pdata == NULL) {
+		dev_dbg(&pdev->dev, "no platform data specified\n");
+		return -EINVAL;
+	}
+
+	nxp = kzalloc(sizeof(struct nxp_74hc153_chip), GFP_KERNEL);
+	if (nxp == NULL) {
+		dev_err(&pdev->dev, "no memory for private data\n");
+		return -ENOMEM;
+	}
+
+	err = gpio_request(pdata->gpio_pin_s0, dev_name(&pdev->dev));
+	if (err) {
+		dev_err(&pdev->dev, "unable to claim gpio %u, err=%d\n",
+			pdata->gpio_pin_s0, err);
+		goto err_free_nxp;
+	}
+
+	err = gpio_request(pdata->gpio_pin_s1, dev_name(&pdev->dev));
+	if (err) {
+		dev_err(&pdev->dev, "unable to claim gpio %u, err=%d\n",
+			pdata->gpio_pin_s1, err);
+		goto err_free_s0;
+	}
+
+	err = gpio_request(pdata->gpio_pin_1y, dev_name(&pdev->dev));
+	if (err) {
+		dev_err(&pdev->dev, "unable to claim gpio %u, err=%d\n",
+			pdata->gpio_pin_1y, err);
+		goto err_free_s1;
+	}
+
+	err = gpio_request(pdata->gpio_pin_2y, dev_name(&pdev->dev));
+	if (err) {
+		dev_err(&pdev->dev, "unable to claim gpio %u, err=%d\n",
+			pdata->gpio_pin_2y, err);
+		goto err_free_1y;
+	}
+
+	err = gpio_direction_output(pdata->gpio_pin_s0, 0);
+	if (err) {
+		dev_err(&pdev->dev,
+			"unable to set direction of gpio %u, err=%d\n",
+			pdata->gpio_pin_s0, err);
+		goto err_free_2y;
+	}
+
+	err = gpio_direction_output(pdata->gpio_pin_s1, 0);
+	if (err) {
+		dev_err(&pdev->dev,
+			"unable to set direction of gpio %u, err=%d\n",
+			pdata->gpio_pin_s1, err);
+		goto err_free_2y;
+	}
+
+	err = gpio_direction_input(pdata->gpio_pin_1y);
+	if (err) {
+		dev_err(&pdev->dev,
+			"unable to set direction of gpio %u, err=%d\n",
+			pdata->gpio_pin_1y, err);
+		goto err_free_2y;
+	}
+
+	err = gpio_direction_input(pdata->gpio_pin_2y);
+	if (err) {
+		dev_err(&pdev->dev,
+			"unable to set direction of gpio %u, err=%d\n",
+			pdata->gpio_pin_2y, err);
+		goto err_free_2y;
+	}
+
+	nxp->parent = &pdev->dev;
+	mutex_init(&nxp->lock);
+
+	gc = &nxp->gpio_chip;
+
+	gc->direction_input  = nxp_74hc153_direction_input;
+	gc->direction_output = nxp_74hc153_direction_output;
+	gc->get = nxp_74hc153_get_value;
+	gc->set = nxp_74hc153_set_value;
+	gc->can_sleep = 1;
+
+	gc->base = pdata->gpio_base;
+	gc->ngpio = NXP_74HC153_NUM_GPIOS;
+	gc->label = dev_name(nxp->parent);
+	gc->dev = nxp->parent;
+	gc->owner = THIS_MODULE;
+
+	err = gpiochip_add(&nxp->gpio_chip);
+	if (err) {
+		dev_err(&pdev->dev, "unable to add gpio chip, err=%d\n", err);
+		goto err_free_2y;
+	}
+
+	platform_set_drvdata(pdev, nxp);
+	return 0;
+
+ err_free_2y:
+	gpio_free(pdata->gpio_pin_2y);
+ err_free_1y:
+	gpio_free(pdata->gpio_pin_1y);
+ err_free_s1:
+	gpio_free(pdata->gpio_pin_s1);
+ err_free_s0:
+	gpio_free(pdata->gpio_pin_s0);
+ err_free_nxp:
+	kfree(nxp);
+	return err;
+}
+
+static int nxp_74hc153_remove(struct platform_device *pdev)
+{
+	struct nxp_74hc153_chip *nxp = platform_get_drvdata(pdev);
+	struct nxp_74hc153_platform_data *pdata = pdev->dev.platform_data;
+
+	if (nxp) {
+		int err;
+
+		err = gpiochip_remove(&nxp->gpio_chip);
+		if (err) {
+			dev_err(&pdev->dev,
+				"unable to remove gpio chip, err=%d\n",
+				err);
+			return err;
+		}
+
+		gpio_free(pdata->gpio_pin_2y);
+		gpio_free(pdata->gpio_pin_1y);
+		gpio_free(pdata->gpio_pin_s1);
+		gpio_free(pdata->gpio_pin_s0);
+
+		kfree(nxp);
+		platform_set_drvdata(pdev, NULL);
+	}
+
+	return 0;
+}
+
+static struct platform_driver nxp_74hc153_driver = {
+	.probe		= nxp_74hc153_probe,
+	.remove		= __devexit_p(nxp_74hc153_remove),
+	.driver = {
+		.name	= NXP_74HC153_DRIVER_NAME,
+		.owner	= THIS_MODULE,
+	},
+};
+
+static int __init nxp_74hc153_init(void)
+{
+	return platform_driver_register(&nxp_74hc153_driver);
+}
+subsys_initcall(nxp_74hc153_init);
+
+static void __exit nxp_74hc153_exit(void)
+{
+	platform_driver_unregister(&nxp_74hc153_driver);
+}
+module_exit(nxp_74hc153_exit);
+
+MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
+MODULE_DESCRIPTION("GPIO expander driver for NXP 74HC153");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" NXP_74HC153_DRIVER_NAME);
diff --git a/target/linux/ar71xx/files/include/linux/nxp_74hc153.h b/target/linux/ar71xx/files/include/linux/nxp_74hc153.h
new file mode 100644
index 0000000..20b8845
--- /dev/null
+++ b/target/linux/ar71xx/files/include/linux/nxp_74hc153.h
@@ -0,0 +1,24 @@
+/*
+ *  NXP 74HC153 - Dual 4-input multiplexer defines
+ *
+ *  Copyright (C) 2010 Gabor Juhos <juhosg@openwrt.org>
+ *
+ *  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.
+ */
+
+#ifndef _NXP_74HC153_H
+#define _NXP_74HC153_H
+
+#define NXP_74HC153_DRIVER_NAME "nxp-74hc153"
+
+struct nxp_74hc153_platform_data {
+	unsigned	gpio_base;
+	unsigned	gpio_pin_s0;
+	unsigned	gpio_pin_s1;
+	unsigned	gpio_pin_1y;
+	unsigned	gpio_pin_2y;
+};
+
+#endif /* _NXP_74HC153_H */