diff options
Diffstat (limited to 'arch/arm/mach-wmt/gpio_ctrl.c')
| -rwxr-xr-x | arch/arm/mach-wmt/gpio_ctrl.c | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/arch/arm/mach-wmt/gpio_ctrl.c b/arch/arm/mach-wmt/gpio_ctrl.c new file mode 100755 index 00000000..8c1c2d76 --- /dev/null +++ b/arch/arm/mach-wmt/gpio_ctrl.c @@ -0,0 +1,202 @@ +/*
+ * procfs1.c - create a "file" in /proc
+ *
+ */
+#include <linux/module.h> /* Specifically, a module */
+#include <linux/kernel.h> /* We're doing kernel work */
+#include <linux/proc_fs.h> /* Necessary because we use the proc fs */
+#include <linux/gpio.h>
+#include <mach/wmt_iomux.h>
+#include <asm/uaccess.h> //for copy_from_user
+#include <linux/delay.h> // for mdelay
+
+#define DRIVER_AUTHOR "rubbitxiao "
+#define DRIVER_DESC "printer power control"
+
+
+#define procfs_name "gpio_ctrl"
+
+extern int wmt_getsyspara(char *varname, unsigned char *varval, int *varlen);
+extern struct proc_dir_entry proc_root;
+/**
+ * This structure hold information about the /proc file
+ *
+ */
+static struct proc_dir_entry *Our_Proc_File;
+
+int power_on = -1; //control printer power on/off
+int lid_stat = -1; //inflext printer lid open or close status
+
+enum{
+ LOW=0,
+ HIGH,
+};
+
+/* Put data into the proc fs file.
+ *
+ * Arguments
+ * =========
+ * 1. The buffer where the data is to be inserted, if
+ * you decide to use it.
+ * 2. A pointer to a pointer to characters. This is
+ * useful if you don't want to use the buffer
+ * allocated by the kernel.
+ * 3. The current position in the file
+ * 4. The size of the buffer in the first argument.
+ * 5. Write a "1" here to indicate EOF.
+ * 6. A pointer to data (useful in case one common
+ * read for multiple /proc/... entries)
+ *
+ * Usage and Return Value
+ * ======================
+ * A return value of zero means you have no further
+ * information at this time (end of file). A negative
+ * return value is an error condition.
+ *
+ * For More Information
+ * ====================
+ * The way I discovered what to do with this function
+ * wasn't by reading documentation, but by reading the
+ * code which used it. I just looked to see what uses
+ * the get_info field of proc_dir_entry struct (I used a
+ * combination of find and grep, if you're interested),
+ * and I saw that it is used in <kernel source
+ * directory>/fs/proc/array.c.
+ *
+ * If something is unknown about the kernel, this is
+ * usually the way to go. In Linux we have the great
+ * advantage of having the kernel source code for
+ * free - use it.
+ */
+static int
+procfile_read(char *buffer,
+ char **buffer_location,
+ off_t offset, int buffer_length, int *eof, void *data)
+{
+ int ret;
+ int value = -1;
+
+ if (offset > 0) {
+ /* we have finished to read, return 0 */
+ ret = 0;
+ } else {
+ if(lid_stat >=0){
+ gpio_direction_input(lid_stat);
+ value = __gpio_get_value(lid_stat);
+ /* fill the buffer, return the buffer size */
+ ret = sprintf(buffer,"%d",value);
+ }else{
+ printk("err! have not set wmt.gpo.printer uboot variant\n");
+ ret = -1;
+ }
+ }
+
+ return ret;
+}
+
+
+static int procfile_write(struct file *file, const char __user *buffer,
+ unsigned long count, void *data)
+{
+ int ret = 0;
+ char tmp[128];
+ int num;
+
+ int on = 0;
+
+ if(buffer && !copy_from_user(tmp, buffer, sizeof(tmp))) {
+
+ num = sscanf(tmp, "%d", &on);
+ printk("your input power on/off:%d\n",on);
+ if(power_on<0){
+ printk("err! have not set wmt.gpo.printer uboot variant\n");
+ return -1;
+ }
+ if(on){
+ gpio_direction_output(power_on, HIGH);
+ mdelay(200);
+ printk("power on printer\n");
+ }else{
+ gpio_direction_output(power_on, LOW);
+ printk("power off printer\n");
+ }
+
+ return strlen(tmp);
+ }else{
+ printk("copy_from_user failed or buffer is null\n");
+ return -1;
+ }
+}
+
+
+static int __init wifi_proc_init(void)
+{
+ int retval = 0;
+ int varlen = 127;
+ char buf[200]={0};
+
+ Our_Proc_File = create_proc_entry(procfs_name, 0644, NULL);
+
+ if (Our_Proc_File == NULL) {
+ remove_proc_entry(procfs_name, NULL);
+ printk(KERN_ALERT "Error: Could not initialize /proc/%s\n",
+ procfs_name);
+ return -ENOMEM;
+ }
+ /*
+ * wmt.gpo.printer format as follows:
+ * power_on:lid_stat
+ * for example: setenv wmt.gpo.printer 153:3
+ * gpio8 for power on; gpio9 for lid status
+ */
+ retval = wmt_getsyspara("wmt.gpo.printer", buf, &varlen);
+ if(!retval)
+ {
+ sscanf(buf, "%d:%d",&power_on,&lid_stat);
+ printk("power_on:%d,lid_stat:%d\n", power_on,lid_stat);
+ //request gpio for printer power control
+ retval = gpio_request(power_on, "printer power pin");
+ if(retval < 0) {
+ printk("reques gpio:%x failed!!! for printer power pin\n",power_on);
+ return -1;
+ }else{
+ printk("request gpio:%d for printer power pin success!!!\n", power_on);
+ }
+ //request gpio for printer lid status
+ retval = gpio_request(lid_stat, "printer lid status");
+ if(retval < 0) {
+ printk("reques gpio:%x failed!!! for printer lid status\n",lid_stat);
+ return -1;
+ }else{
+ printk("request gpio:%d for printer lid status success!!!\n", lid_stat);
+ }
+ }else{
+ printk("have not set wmt.gpo.printer");
+ }
+
+ Our_Proc_File->read_proc = procfile_read;
+ Our_Proc_File->write_proc = procfile_write;
+ Our_Proc_File->mode = S_IFREG | S_IRUGO;
+ Our_Proc_File->uid = 0;
+ Our_Proc_File->gid = 0;
+ Our_Proc_File->size = 37;
+
+ return 0; /* everything is ok */
+}
+
+static void __exit wifi_proc_uninit(void)
+{
+ remove_proc_entry(procfs_name, NULL);
+ if(power_on)
+ gpio_free(power_on);
+ if(lid_stat)
+ gpio_free(lid_stat);
+}
+
+
+module_init(wifi_proc_init);
+module_exit(wifi_proc_uninit);
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+MODULE_VERSION("1.0");
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