platform/chrome: use sysfs_emit_at() instead of scnprintf()

Follow the advice in Documentation/filesystems/sysfs.rst:
show() should only use sysfs_emit() or sysfs_emit_at() when formatting
the value to be returned to user space.

Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20221205061042.1774769-1-tzungbi@kernel.org

diff --git a/drivers/platform/chrome/cros_ec_sysfs.c b/drivers/platform/chrome/cros_ec_sysfs.c
index e45e57cee3a87b20895c99e5070920c7471e8453..09e3bf5e8ec69d0b3f6aa1fcb420b44f24f7bca5 100644 (file)
--- a/drivers/platform/chrome/cros_ec_sysfs.c
+++ b/drivers/platform/chrome/cros_ec_sysfs.c
@@ -27,10 +27,9 @@ static ssize_t reboot_show(struct device *dev,
 {
        int count = 0;
 
-       count += scnprintf(buf + count, PAGE_SIZE - count,
-                          "ro|rw|cancel|cold|disable-jump|hibernate|cold-ap-off");
-       count += scnprintf(buf + count, PAGE_SIZE - count,
-                          " [at-shutdown]\n");
+       count += sysfs_emit_at(buf, count,
+                              "ro|rw|cancel|cold|disable-jump|hibernate|cold-ap-off");
+       count += sysfs_emit_at(buf, count, " [at-shutdown]\n");
        return count;
 }
 
@@ -138,12 +137,9 @@ static ssize_t version_show(struct device *dev,
        /* Strings should be null-terminated, but let's be sure. */
        r_ver->version_string_ro[sizeof(r_ver->version_string_ro) - 1] = '\0';
        r_ver->version_string_rw[sizeof(r_ver->version_string_rw) - 1] = '\0';
-       count += scnprintf(buf + count, PAGE_SIZE - count,
-                          "RO version:    %s\n", r_ver->version_string_ro);
-       count += scnprintf(buf + count, PAGE_SIZE - count,
-                          "RW version:    %s\n", r_ver->version_string_rw);
-       count += scnprintf(buf + count, PAGE_SIZE - count,
-                          "Firmware copy: %s\n",
+       count += sysfs_emit_at(buf, count, "RO version:    %s\n", r_ver->version_string_ro);
+       count += sysfs_emit_at(buf, count, "RW version:    %s\n", r_ver->version_string_rw);
+       count += sysfs_emit_at(buf, count, "Firmware copy: %s\n",
                           (r_ver->current_image < ARRAY_SIZE(image_names) ?
                            image_names[r_ver->current_image] : "?"));
 
@@ -152,13 +148,12 @@ static ssize_t version_show(struct device *dev,
        msg->insize = EC_HOST_PARAM_SIZE;
        ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
        if (ret < 0) {
-               count += scnprintf(buf + count, PAGE_SIZE - count,
+               count += sysfs_emit_at(buf, count,
                                   "Build info:    XFER / EC ERROR %d / %d\n",
                                   ret, msg->result);
        } else {
                msg->data[EC_HOST_PARAM_SIZE - 1] = '\0';
-               count += scnprintf(buf + count, PAGE_SIZE - count,
-                                  "Build info:    %s\n", msg->data);
+               count += sysfs_emit_at(buf, count, "Build info:    %s\n", msg->data);
        }
 
        /* Get chip info. */
@@ -166,7 +161,7 @@ static ssize_t version_show(struct device *dev,
        msg->insize = sizeof(*r_chip);
        ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
        if (ret < 0) {
-               count += scnprintf(buf + count, PAGE_SIZE - count,
+               count += sysfs_emit_at(buf, count,
                                   "Chip info:     XFER / EC ERROR %d / %d\n",
                                   ret, msg->result);
        } else {
@@ -175,12 +170,9 @@ static ssize_t version_show(struct device *dev,
                r_chip->vendor[sizeof(r_chip->vendor) - 1] = '\0';
                r_chip->name[sizeof(r_chip->name) - 1] = '\0';
                r_chip->revision[sizeof(r_chip->revision) - 1] = '\0';
-               count += scnprintf(buf + count, PAGE_SIZE - count,
-                                  "Chip vendor:   %s\n", r_chip->vendor);
-               count += scnprintf(buf + count, PAGE_SIZE - count,
-                                  "Chip name:     %s\n", r_chip->name);
-               count += scnprintf(buf + count, PAGE_SIZE - count,
-                                  "Chip revision: %s\n", r_chip->revision);
+               count += sysfs_emit_at(buf, count, "Chip vendor:   %s\n", r_chip->vendor);
+               count += sysfs_emit_at(buf, count, "Chip name:     %s\n", r_chip->name);
+               count += sysfs_emit_at(buf, count, "Chip revision: %s\n", r_chip->revision);
        }
 
        /* Get board version */
@@ -188,13 +180,13 @@ static ssize_t version_show(struct device *dev,
        msg->insize = sizeof(*r_board);
        ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
        if (ret < 0) {
-               count += scnprintf(buf + count, PAGE_SIZE - count,
+               count += sysfs_emit_at(buf, count,
                                   "Board version: XFER / EC ERROR %d / %d\n",
                                   ret, msg->result);
        } else {
                r_board = (struct ec_response_board_version *)msg->data;
 
-               count += scnprintf(buf + count, PAGE_SIZE - count,
+               count += sysfs_emit_at(buf, count,
                                   "Board version: %d\n",
                                   r_board->board_version);
        }