gpio: chardev interface / multiple gpio support for sysfs

Signed-off-by: Mihai Stefanescu <mihai.t.gh.stefanescu@gmail.com>
Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>

src/gpio/gpio_chardev.c

@@ -50,38 +50,74 @@
 void
 _mraa_free_gpio_groups(mraa_gpio_context dev)
 {
-    mraa_gpiod_group_t gpio_group = dev->gpio_group;
+    mraa_gpiod_group_t gpio_iter;
 
-    for (int i = 0; i < dev->num_chips; ++i) {
-        if (gpio_group[i].is_required) {
-            free(gpio_group[i].gpio_lines);
-            free(gpio_group[i].rw_values);
-            free(gpio_group[i].gpio_group_to_pins_table);
+    for_each_gpio_group(gpio_iter, dev) {
+        free(gpio_iter->gpio_lines);
+        free(gpio_iter->rw_values);
+        free(gpio_iter->gpio_group_to_pins_table);
 
-            if (gpio_group[i].gpiod_handle != -1) {
-                close(gpio_group[i].gpiod_handle);
-            }
-
-            if (gpio_group[i].event_handles != NULL) {
-                for (int j = 0; j < gpio_group[i].num_gpio_lines; ++j) {
-                    close(gpio_group[i].event_handles[j]);
-                }
-
-                free(gpio_group[i].event_handles);
-            }
-
-            close(gpio_group[i].dev_fd);
+        if (gpio_iter->gpiod_handle != -1) {
+            close(gpio_iter->gpiod_handle);
         }
+
+        if (gpio_iter->event_handles != NULL) {
+            for (int j = 0; j < gpio_iter->num_gpio_lines; ++j) {
+                close(gpio_iter->event_handles[j]);
+            }
+
+            free(gpio_iter->event_handles);
+        }
+
+        close(gpio_iter->dev_fd);
     }
 
-    free(gpio_group);
+    free(dev->gpio_group);
 
     /* Also delete the pin to gpio chip mapping. */
     free(dev->pin_to_gpio_table);
+
+    /* User provided array saved internally. */
+    free(dev->provided_pins);
+
+    /* Finally, delete event array. */
+    free(dev->events);
+}
+
+void
+_mraa_close_gpio_event_handles(mraa_gpio_context dev)
+{
+    mraa_gpiod_group_t gpio_iter;
+
+    for_each_gpio_group(gpio_iter, dev) {
+        if (gpio_iter->event_handles != NULL) {
+            for (int j = 0; j < gpio_iter->num_gpio_lines; ++j) {
+                close(gpio_iter->event_handles[j]);
+            }
+
+            free(gpio_iter->event_handles);
+
+            /* In the end, _mraa_free_gpio_groups will be called. */
+            gpio_iter->event_handles = NULL;
+        }
+    }
+}
+
+void
+_mraa_close_gpio_desc(mraa_gpio_context dev)
+{
+    mraa_gpiod_group_t gpio_iter;
+
+    for_each_gpio_group(gpio_iter, dev) {
+        if (gpio_iter->gpiod_handle != -1) {
+            close(gpio_iter->gpiod_handle);
+            gpio_iter->gpiod_handle = -1;
+        }
+    }
 }
 
 int
-_mraa__mraa_gpiod_ioctl(int fd, unsigned long gpio_request, void* data)
+_mraa_gpiod_ioctl(int fd, unsigned long gpio_request, void* data)
 {
     int status;
 
@@ -319,6 +355,37 @@ mraa_get_line_values(int line_handle, unsigned int num_lines, unsigned char outp
     return status;
 }
 
+
+mraa_boolean_t
+mraa_is_gpio_line_kernel_owned(mraa_gpiod_line_info *linfo)
+{
+    return (linfo->flags & GPIOLINE_FLAG_IS_OUT);
+}
+
+mraa_boolean_t
+mraa_is_gpio_line_dir_out(mraa_gpiod_line_info *linfo)
+{
+    return (linfo->flags & GPIOLINE_FLAG_IS_OUT);
+}
+
+mraa_boolean_t
+mraa_is_gpio_line_active_low(mraa_gpiod_line_info *linfo)
+{
+    return (linfo->flags & GPIOLINE_FLAG_ACTIVE_LOW);
+}
+
+mraa_boolean_t
+mraa_is_gpio_line_open_drain(mraa_gpiod_line_info *linfo)
+{
+    return (linfo->flags & GPIOLINE_FLAG_OPEN_DRAIN);
+}
+
+mraa_boolean_t
+mraa_is_gpio_line_open_source(mraa_gpiod_line_info *linfo)
+{
+    return (linfo->flags & GPIOHANDLE_REQUEST_OPEN_SOURCE);
+}
+
 int
 mraa_get_number_of_gpio_chips()
 {
@@ -343,4 +410,3 @@ mraa_get_number_of_gpio_chips()
     /* Assume opendir() error. */
     return num_chips;
 }
-

src/mraa.c

@@ -57,6 +57,7 @@
 #include "firmata/firmata_mraa.h"
 #include "grovepi/grovepi.h"
 #include "gpio.h"
+#include "gpio/gpio_chardev.h"
 #include "version.h"
 #include "i2c.h"
 #include "pwm.h"
@@ -100,43 +101,7 @@ mraa_set_log_level(int level)
 
 mraa_boolean_t mraa_is_kernel_chardev_interface_compatible()
 {
-    struct utsname buf;
-    int status;
-
-    status = uname(&buf);
-
-    if (status) {
-        syslog(LOG_ERR, "uname() error");
-        return 0;
-    }
-
-    int major, minor;
-    char *token;
-
-    token = strtok(buf.release, ".");
-    if (token == NULL) {
-        syslog(LOG_ERR, "Could not find kernel version major number");
-        return 0;
-    }
-    status = mraa_atoi(token, &major);
-    if (status) {
-        syslog(LOG_ERR, "mraa_atoi() error");
-        return 0;
-    }
-
-    token = strtok(NULL, ".");
-    if (token == NULL) {
-        syslog(LOG_ERR, "Could not find kernel version minor number");
-        return 0;
-    }
-    status = mraa_atoi(token, &minor);
-    if (status) {
-        syslog(LOG_ERR, "mraa_atoi() error");
-        return 0;
-    }
-
-    if (major < 4 || minor < 8) {
-        syslog(LOG_ERR, "Kernel version %i.%i not supported for chardev interface. Need version 4.8 or newer!", major, minor);
+    if (mraa_get_number_of_gpio_chips() <= 0) {
         return 0;
     }