Input: atmel_mxt_ts - optimize reading objects in object sysfs entry

Read each object in a single i2c transaction instead of byte-by-byte

Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 55855b8c2efd2278b71f38dc76752192fca5bc19..94dd1d156a98aaf0a6428bffd03eb907636597d7 100644 (file)
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -479,20 +479,6 @@ static int mxt_read_message(struct mxt_data *data,
                        sizeof(struct mxt_message), message);
 }
 
-static int mxt_read_object(struct mxt_data *data,
-                               u8 type, u8 offset, u8 *val)
-{
-       struct mxt_object *object;
-       u16 reg;
-
-       object = mxt_get_object(data, type);
-       if (!object)
-               return -EINVAL;
-
-       reg = object->start_address;
-       return __mxt_read_reg(data->client, reg + offset, 1, val);
-}
-
 static int mxt_write_object(struct mxt_data *data,
                                 u8 type, u8 offset, u8 val)
 {
@@ -900,7 +886,14 @@ static ssize_t mxt_object_show(struct device *dev,
        int i, j;
        int error;
        u8 val;
+       u8 *obuf;
+
+       /* Pre-allocate buffer large enough to hold max sized object. */
+       obuf = kmalloc(256, GFP_KERNEL);
+       if (!obuf)
+               return -ENOMEM;
 
+       error = 0;
        for (i = 0; i < data->info.object_num; i++) {
                object = data->object_table + i;
 
@@ -914,20 +907,22 @@ static ssize_t mxt_object_show(struct device *dev,
                        continue;
                }
 
+               error = __mxt_read_reg(data->client, object->start_address,
+                               object->size + 1, obuf);
+               if (error)
+                       break;
+
                for (j = 0; j < object->size + 1; j++) {
-                       error = mxt_read_object(data,
-                                               object->type, j, &val);
-                       if (error)
-                               return error;
+                       val = obuf[j];
 
                        count += scnprintf(buf + count, PAGE_SIZE - count,
                                        "\t[%2d]: %02x (%d)\n", j, val, val);
                }
-
                count += scnprintf(buf + count, PAGE_SIZE - count, "\n");
        }
 
-       return count;
+       kfree(obuf);
+       return error ?: count;
 }
 
 static int mxt_load_fw(struct device *dev, const char *fn)