Add generic expander gpio driver for mangoh

linux_kernel_modules/expander/expander.c

+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+#include <linux/version.h>
+#include "expander.h"
+
+/*
+ *-----------------------------------------------------------------------------
+ * Constants
+ *-----------------------------------------------------------------------------
+ */
+#define GENERIC_LED		(4)
+#define PCM_SEL			(5)
+#define SDIO_SEL		(6)
+#define TRI_LED_BLU		(7)
+#define TRI_LED_GRN		(15)
+#define TRI_LED_RED		(10)
+#define BUZZER			(0)
+
+
+struct expander_device {
+	struct platform_device *pdev;
+	atomic_t generic_led_val, pcm_sel_val, sdio_sel_val, buzzer_val,
+	         tri_led_blu_val, tri_led_red_val, tri_led_grn_val;
+	int gpio_expander_base;
+};
+
+
+
+#define CREATE_SYSFS_DEFN(_var, _offset)                                       \
+static ssize_t _var##_show(struct device *dev,               \
+				   struct device_attribute *attr,    \
+				   char *buf)                        \
+{                                                                              \
+	struct expander_device* exp = dev_get_drvdata(dev);             \
+	return sprintf(buf, "%d\n", atomic_read(&exp->_var##_val));           \
+}\
+static int _var##_store(struct device *dev,                  \
+					  struct device_attribute *attr,       \
+					  const char *buf, size_t count)       \
+{                                                                              \
+	struct expander_device* exp = dev_get_drvdata(dev);             \
+	u8 val;                                                                \
+	int ret;							       \
+									       \
+	ret = kstrtou8(buf, 10, &val);					       \
+	if (ret || val > 1)						       \
+		return -EINVAL;						       \
+									       \
+	gpio_set_value_cansleep(exp->gpio_expander_base + _offset, val);       \
+	atomic_set(&exp->_var##_val, val);				       \
+									       \
+	return count;							       \
+}									       \
+static DEVICE_ATTR_RW(_var)
+
+CREATE_SYSFS_DEFN(generic_led, GENERIC_LED);
+CREATE_SYSFS_DEFN(pcm_sel, PCM_SEL);
+CREATE_SYSFS_DEFN(sdio_sel, SDIO_SEL);
+CREATE_SYSFS_DEFN(tri_led_blu, TRI_LED_BLU);
+CREATE_SYSFS_DEFN(tri_led_red, TRI_LED_RED);
+CREATE_SYSFS_DEFN(tri_led_grn, TRI_LED_GRN);
+CREATE_SYSFS_DEFN(buzzer, BUZZER);
+
+
+static void  gpio_initial_status(struct platform_device *pdev,
+				 struct device_attribute *attr,
+			         int function_number,int function_val,
+			         atomic_t *atomic_val)
+{
+
+	struct expander_device* exp = dev_get_drvdata(&pdev->dev);
+	
+
+	devm_gpio_request(&pdev->dev, exp->gpio_expander_base+function_number,
+				dev_name(&pdev->dev));
+
+	atomic_set(atomic_val, function_val);
+
+	 gpio_direction_output(exp->gpio_expander_base+function_number, 
+				    function_val);
+
+	device_create_file(&pdev->dev, attr);
+
+	
+}
+
+static void  gpio_final_status(struct platform_device *pdev,
+                               struct device_attribute *attr,
+			       int function_number,int function_val)
+{
+
+	struct expander_device* exp = dev_get_drvdata(&pdev->dev);
+	
+
+	device_remove_file(&pdev->dev, attr);
+
+	gpio_set_value_cansleep(exp->gpio_expander_base+function_number, function_val);
+
+	
+}
+
+
+
+static int expander_probe(struct platform_device *pdev)
+{
+	struct expander_device* dev;
+	int ret = 0;
+	struct expander_platform_data *pdata = dev_get_platdata(&pdev->dev);
+
+	dev_info(&pdev->dev, "%s(): probe\n", __func__);
+
+	if (!pdata) {
+		ret = -EINVAL;
+		dev_err(&pdev->dev, "Required platform data not provided\n");
+		goto  done;
+	}
+
+	/* Create the driver data and remove the allocated memory when driver 
+	   is removed */
+	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
+	if (!dev) {
+		ret = -ENOMEM;
+		goto done;
+	}
+
+	dev->pdev = pdev;
+ 	dev->gpio_expander_base = pdata->gpio_expander_base;
+        
+        gpio_initial_status(pdev,&dev_attr_generic_led, GENERIC_LED, 0, &dev->generic_led_val); 
+        gpio_initial_status(pdev,&dev_attr_pcm_sel, PCM_SEL, 0, &dev->pcm_sel_val);
+        gpio_initial_status(pdev,&dev_attr_sdio_sel, SDIO_SEL, 0, &dev->sdio_sel_val);  
+        gpio_initial_status(pdev,&dev_attr_tri_led_blu, TRI_LED_BLU, 0, &dev->tri_led_blu_val); 
+        gpio_initial_status(pdev,&dev_attr_tri_led_red, TRI_LED_RED, 0, &dev->tri_led_red_val); 
+ 	gpio_initial_status(pdev,&dev_attr_tri_led_grn, TRI_LED_GRN, 0, &dev->tri_led_grn_val);
+	gpio_initial_status(pdev,&dev_attr_buzzer, BUZZER, 0, &dev->buzzer_val);
+  
+	platform_set_drvdata(pdev, dev);
+
+done:
+	return ret;
+}
+
+static int expander_remove(struct platform_device *pdev)
+{
+//	struct expander_device* dev = dev_get_drvdata(&pdev->dev);
+	dev_info(&pdev->dev, "%s(): remove\n", __func__);
+
+	/* remove sysfs files & set final state values for gpio expander*/
+	gpio_final_status(pdev,&dev_attr_generic_led, GENERIC_LED, 0);
+        gpio_final_status(pdev,&dev_attr_pcm_sel, PCM_SEL, 0);
+	gpio_final_status(pdev,&dev_attr_sdio_sel, SDIO_SEL, 0);
+	gpio_final_status(pdev,&dev_attr_tri_led_blu, TRI_LED_BLU, 0);
+	gpio_final_status(pdev,&dev_attr_tri_led_red, TRI_LED_RED, 0);
+	gpio_final_status(pdev,&dev_attr_tri_led_grn, TRI_LED_GRN, 0);
+	gpio_final_status(pdev,&dev_attr_buzzer, BUZZER, 0);
+
+	return 0;
+}
+
+static const struct platform_device_id yellow_expander_ids[] = {
+	{"expander", (kernel_ulong_t)0},
+	{},
+};
+MODULE_DEVICE_TABLE(platform, yellow_expander_ids);
+
+static struct platform_driver expander_driver = {
+	.probe		= expander_probe,
+	.remove		= expander_remove,
+	.driver		= {
+		.name	= "expander",
+		.owner	= THIS_MODULE,
+		.bus	= &platform_bus_type,
+	},
+	.id_table	= yellow_expander_ids,
+};
+
+static int __init expander_init(void)
+{
+	platform_driver_register(&expander_driver);
+	return 0;
+}
+
+static void __exit expander_exit(void)
+{
+	platform_driver_unregister(&expander_driver);
+}
+
+module_init(expander_init);
+module_exit(expander_exit);
+
+MODULE_ALIAS("platform:expander");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Sierra Wireless");
+MODULE_DESCRIPTION("EXPANDER driver");
+MODULE_VERSION("0.1");

linux_kernel_modules/expander/expander.h

+#ifndef EXPANDER_H
+#define EXPANDER_H
+
+struct expander_platform_data {
+	int gpio_expander_base;
+};
+
+#endif /* EXPANDER_H */

linux_kernel_modules/expander/expander.mdef

+sources:
+{
+    expander.c
+}
+
+cflags:
+{
+//    -DDEBUG
+}
+
+params:
+{
+}