Changeset ca97cad in mainline for uspace/lib/libc

Timestamp:

2010-05-06T11:42:55Z (15 years ago)

Author:

Lenka Trochtova <trochtova.lenka@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

ab1aa871

Parents:

ba95e8f

Message:

writing to serial port using character interface

File:

• uspace/lib/libc/generic/device/char.c (modified) (2 diffs)

uspace/lib/libc/generic/device/char.c

@@ -40 +40 @@
 #include <stdio.h>
 
-
-int read_dev(int dev_phone, void *buf, size_t len)
-{       
+/** Read to or write from the device using its character interface.
+ * 
+ * Helper function.
+ * 
+ * @param dev_phone phone to the device.
+ * @param buf the buffer for the data read from or written to the device.
+ * @param len the maximum length of the data to be read or written.
+ * @param read read from the device if true, write to it otherwise.
+ * 
+ * @return non-negative number of bytes actually read from or written to the device on success,
+ * negative error number otherwise.
+ * 
+ */
+static int rw_dev(int dev_phone, void *buf, size_t len, bool read) 
+{
         ipc_call_t answer;
         
         async_serialize_start();
         
-        aid_t req = async_send_1(dev_phone, DEV_IFACE_ID(CHAR_DEV_IFACE), CHAR_READ_DEV, &answer);
+        aid_t req;
+        int rc;
         
-        int rc = async_data_read_start(dev_phone, buf, len);
+        if (read) {
+                req = async_send_1(dev_phone, DEV_IFACE_ID(CHAR_DEV_IFACE), CHAR_READ_DEV, &answer);
+                rc = async_data_read_start(dev_phone, buf, len);                
+        } else {
+                req = async_send_1(dev_phone, DEV_IFACE_ID(CHAR_DEV_IFACE), CHAR_WRITE_DEV, &answer);
+                rc = async_data_write_start(dev_phone, buf, len);
+        }
         
         if (rc != EOK) {
@@ -70 +89 @@
         }
         
-        return IPC_GET_ARG1(answer);
+        return IPC_GET_ARG1(answer);    
 }
 
+/** Read from the device using its character interface.
+ * 
+ * @param dev_phone phone to the device.
+ * @param buf the output buffer for the data read from the device.
+ * @param len the maximum length of the data to be read.
+ * 
+ * @return non-negative number of bytes actually read from the device on success, negative error number otherwise.
+ */
+int read_dev(int dev_phone, void *buf, size_t len)
+{       
+        return rw_dev(dev_phone, buf, len, true);
+}
+
+/** Write to the device using its character interface.
+ * 
+ * @param dev_phone phone to the device.
+ * @param buf the input buffer containg the data to be written to the device.
+ * @param len the maximum length of the data to be written.
+ * 
+ * @return non-negative number of bytes actually written to the device on success, negative error number otherwise.
+ */
 int write_dev(int dev_phone, void *buf, size_t len)
 {
-        // TODO
-        return 0;
+        return rw_dev(dev_phone, buf, len, false);
 }