platform/chrome: Create sysfs attributes for the ChromeOS EC
authorBill Richardson <wfrichar@chromium.org>
Mon, 2 Feb 2015 11:26:27 +0000 (12:26 +0100)
committerOlof Johansson <olof@lixom.net>
Thu, 26 Feb 2015 23:45:12 +0000 (15:45 -0800)
This adds the first few sysfs attributes for the Chrome OS EC. These
controls are made available under /sys/devices/virtual/chromeos/cros_ec

    flashinfo   - display current flash info
    reboot      - tell the EC to reboot in various ways
    version     - information about the EC software and hardware

Future changes will build on this to add additional controls.

From a root shell, you should be able to do things like this:

    cd /sys/devices/virtual/chromeos/cros_ec
    cat flashinfo
    cat version
    echo rw > reboot
    cat version
    echo ro > reboot
    cat version
    echo rw > reboot
    cat version
    echo cold > reboot

That last command will reboot the AP too.

Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-by: Olof Johansson <olofj@chromium.org>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Tested-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
drivers/platform/chrome/Makefile
drivers/platform/chrome/cros_ec_dev.c
drivers/platform/chrome/cros_ec_dev.h
drivers/platform/chrome/cros_ec_sysfs.c [new file with mode: 0644]

index ec682900f8896585c843c186bf30372775ba4126..34b631ceff676347d62e0ea02bf9e1bd5872f776 100644 (file)
@@ -1,5 +1,6 @@
 
 obj-$(CONFIG_CHROMEOS_LAPTOP)  += chromeos_laptop.o
 obj-$(CONFIG_CHROMEOS_PSTORE)  += chromeos_pstore.o
-obj-$(CONFIG_CROS_EC_CHARDEV)   += cros_ec_dev.o
+cros_ec_devs-objs               := cros_ec_dev.o cros_ec_sysfs.o
+obj-$(CONFIG_CROS_EC_CHARDEV)   += cros_ec_devs.o
 obj-$(CONFIG_CROS_EC_LPC)       += cros_ec_lpc.o
index 94c1442d51047e76fc888c505bfbc97942998db4..33f37ad36892c614e2e1223cb5f89995f78b8b40 100644 (file)
@@ -198,6 +198,9 @@ static int ec_device_probe(struct platform_device *pdev)
                return retval;
        }
 
+       /* Initialize extra interfaces */
+       ec_dev_sysfs_init(ec);
+
        return 0;
 }
 
@@ -205,6 +208,7 @@ static int ec_device_remove(struct platform_device *pdev)
 {
        struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent);
 
+       ec_dev_sysfs_remove(ec);
        device_destroy(cros_class, MKDEV(ec_major, 0));
        cdev_del(&ec->cdev);
        return 0;
index 15c54c4c5531d18afadffbcdce7aab9d29d3bc9e..f03613290ecf73da8839e808a1fc22e0b40963f3 100644 (file)
@@ -44,4 +44,7 @@ struct cros_ec_readmem {
 #define CROS_EC_DEV_IOCXCMD   _IOWR(CROS_EC_DEV_IOC, 0, struct cros_ec_command)
 #define CROS_EC_DEV_IOCRDMEM  _IOWR(CROS_EC_DEV_IOC, 1, struct cros_ec_readmem)
 
+void ec_dev_sysfs_init(struct cros_ec_device *);
+void ec_dev_sysfs_remove(struct cros_ec_device *);
+
 #endif /* _CROS_EC_DEV_H_ */
diff --git a/drivers/platform/chrome/cros_ec_sysfs.c b/drivers/platform/chrome/cros_ec_sysfs.c
new file mode 100644 (file)
index 0000000..fb62ab6
--- /dev/null
@@ -0,0 +1,271 @@
+/*
+ * cros_ec_sysfs - expose the Chrome OS EC through sysfs
+ *
+ * Copyright (C) 2014 Google, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define pr_fmt(fmt) "cros_ec_sysfs: " fmt
+
+#include <linux/ctype.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/kobject.h>
+#include <linux/mfd/cros_ec.h>
+#include <linux/mfd/cros_ec_commands.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/printk.h>
+#include <linux/stat.h>
+#include <linux/types.h>
+#include <linux/uaccess.h>
+
+#include "cros_ec_dev.h"
+
+/* Accessor functions */
+
+static ssize_t show_ec_reboot(struct device *dev,
+                             struct device_attribute *attr, char *buf)
+{
+       int count = 0;
+
+       count += scnprintf(buf + count, PAGE_SIZE - count,
+                          "ro|rw|cancel|cold|disable-jump|hibernate");
+       count += scnprintf(buf + count, PAGE_SIZE - count,
+                          " [at-shutdown]\n");
+       return count;
+}
+
+static ssize_t store_ec_reboot(struct device *dev,
+                              struct device_attribute *attr,
+                              const char *buf, size_t count)
+{
+       static const struct {
+               const char * const str;
+               uint8_t cmd;
+               uint8_t flags;
+       } words[] = {
+               {"cancel",       EC_REBOOT_CANCEL, 0},
+               {"ro",           EC_REBOOT_JUMP_RO, 0},
+               {"rw",           EC_REBOOT_JUMP_RW, 0},
+               {"cold",         EC_REBOOT_COLD, 0},
+               {"disable-jump", EC_REBOOT_DISABLE_JUMP, 0},
+               {"hibernate",    EC_REBOOT_HIBERNATE, 0},
+               {"at-shutdown",  -1, EC_REBOOT_FLAG_ON_AP_SHUTDOWN},
+       };
+       struct cros_ec_command msg = { 0 };
+       struct ec_params_reboot_ec *param =
+               (struct ec_params_reboot_ec *)msg.outdata;
+       int got_cmd = 0, offset = 0;
+       int i;
+       int ret;
+       struct cros_ec_device *ec = dev_get_drvdata(dev);
+
+       param->flags = 0;
+       while (1) {
+               /* Find word to start scanning */
+               while (buf[offset] && isspace(buf[offset]))
+                       offset++;
+               if (!buf[offset])
+                       break;
+
+               for (i = 0; i < ARRAY_SIZE(words); i++) {
+                       if (!strncasecmp(words[i].str, buf+offset,
+                                        strlen(words[i].str))) {
+                               if (words[i].flags) {
+                                       param->flags |= words[i].flags;
+                               } else {
+                                       param->cmd = words[i].cmd;
+                                       got_cmd = 1;
+                               }
+                               break;
+                       }
+               }
+
+               /* On to the next word, if any */
+               while (buf[offset] && !isspace(buf[offset]))
+                       offset++;
+       }
+
+       if (!got_cmd)
+               return -EINVAL;
+
+       msg.command = EC_CMD_REBOOT_EC;
+       msg.outsize = sizeof(param);
+       ret = cros_ec_cmd_xfer(ec, &msg);
+       if (ret < 0)
+               return ret;
+       if (msg.result != EC_RES_SUCCESS) {
+               dev_dbg(ec->dev, "EC result %d\n", msg.result);
+               return -EINVAL;
+       }
+
+       return count;
+}
+
+static ssize_t show_ec_version(struct device *dev,
+                              struct device_attribute *attr, char *buf)
+{
+       static const char * const image_names[] = {"unknown", "RO", "RW"};
+       struct ec_response_get_version *r_ver;
+       struct ec_response_get_chip_info *r_chip;
+       struct ec_response_board_version *r_board;
+       struct cros_ec_command msg = { 0 };
+       int ret;
+       int count = 0;
+       struct cros_ec_device *ec = dev_get_drvdata(dev);
+
+       /* Get versions. RW may change. */
+       msg.command = EC_CMD_GET_VERSION;
+       msg.insize = sizeof(*r_ver);
+       ret = cros_ec_cmd_xfer(ec, &msg);
+       if (ret < 0)
+               return ret;
+       if (msg.result != EC_RES_SUCCESS)
+               return scnprintf(buf, PAGE_SIZE,
+                                "ERROR: EC returned %d\n", msg.result);
+
+       r_ver = (struct ec_response_get_version *)msg.indata;
+       /* 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",
+                          (r_ver->current_image < ARRAY_SIZE(image_names) ?
+                           image_names[r_ver->current_image] : "?"));
+
+       /* Get build info. */
+       msg.command = EC_CMD_GET_BUILD_INFO;
+       msg.insize = sizeof(msg.indata);
+       ret = cros_ec_cmd_xfer(ec, &msg);
+       if (ret < 0)
+               count += scnprintf(buf + count, PAGE_SIZE - count,
+                                  "Build info:    XFER ERROR %d\n", ret);
+       else if (msg.result != EC_RES_SUCCESS)
+               count += scnprintf(buf + count, PAGE_SIZE - count,
+                                  "Build info:    EC error %d\n", msg.result);
+       else {
+               msg.indata[sizeof(msg.indata) - 1] = '\0';
+               count += scnprintf(buf + count, PAGE_SIZE - count,
+                                  "Build info:    %s\n", msg.indata);
+       }
+
+       /* Get chip info. */
+       msg.command = EC_CMD_GET_CHIP_INFO;
+       msg.insize = sizeof(*r_chip);
+       ret = cros_ec_cmd_xfer(ec, &msg);
+       if (ret < 0)
+               count += scnprintf(buf + count, PAGE_SIZE - count,
+                                  "Chip info:     XFER ERROR %d\n", ret);
+       else if (msg.result != EC_RES_SUCCESS)
+               count += scnprintf(buf + count, PAGE_SIZE - count,
+                                  "Chip info:     EC error %d\n", msg.result);
+       else {
+               r_chip = (struct ec_response_get_chip_info *)msg.indata;
+
+               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);
+       }
+
+       /* Get board version */
+       msg.command = EC_CMD_GET_BOARD_VERSION;
+       msg.insize = sizeof(*r_board);
+       ret = cros_ec_cmd_xfer(ec, &msg);
+       if (ret < 0)
+               count += scnprintf(buf + count, PAGE_SIZE - count,
+                                  "Board version: XFER ERROR %d\n", ret);
+       else if (msg.result != EC_RES_SUCCESS)
+               count += scnprintf(buf + count, PAGE_SIZE - count,
+                                  "Board version: EC error %d\n", msg.result);
+       else {
+               r_board = (struct ec_response_board_version *)msg.indata;
+
+               count += scnprintf(buf + count, PAGE_SIZE - count,
+                                  "Board version: %d\n",
+                                  r_board->board_version);
+       }
+
+       return count;
+}
+
+static ssize_t show_ec_flashinfo(struct device *dev,
+                                struct device_attribute *attr, char *buf)
+{
+       struct ec_response_flash_info *resp;
+       struct cros_ec_command msg = { 0 };
+       int ret;
+       struct cros_ec_device *ec = dev_get_drvdata(dev);
+
+       /* The flash info shouldn't ever change, but ask each time anyway. */
+       msg.command = EC_CMD_FLASH_INFO;
+       msg.insize = sizeof(*resp);
+       ret = cros_ec_cmd_xfer(ec, &msg);
+       if (ret < 0)
+               return ret;
+       if (msg.result != EC_RES_SUCCESS)
+               return scnprintf(buf, PAGE_SIZE,
+                                "ERROR: EC returned %d\n", msg.result);
+
+       resp = (struct ec_response_flash_info *)msg.indata;
+
+       return scnprintf(buf, PAGE_SIZE,
+                        "FlashSize %d\nWriteSize %d\n"
+                        "EraseSize %d\nProtectSize %d\n",
+                        resp->flash_size, resp->write_block_size,
+                        resp->erase_block_size, resp->protect_block_size);
+}
+
+/* Module initialization */
+
+static DEVICE_ATTR(reboot, S_IWUSR | S_IRUGO, show_ec_reboot, store_ec_reboot);
+static DEVICE_ATTR(version, S_IRUGO, show_ec_version, NULL);
+static DEVICE_ATTR(flashinfo, S_IRUGO, show_ec_flashinfo, NULL);
+
+static struct attribute *__ec_attrs[] = {
+       &dev_attr_reboot.attr,
+       &dev_attr_version.attr,
+       &dev_attr_flashinfo.attr,
+       NULL,
+};
+
+static struct attribute_group ec_attr_group = {
+       .attrs = __ec_attrs,
+};
+
+void ec_dev_sysfs_init(struct cros_ec_device *ec)
+{
+       int error;
+
+       error = sysfs_create_group(&ec->vdev->kobj, &ec_attr_group);
+       if (error)
+               pr_warn("failed to create group: %d\n", error);
+}
+
+void ec_dev_sysfs_remove(struct cros_ec_device *ec)
+{
+       sysfs_remove_group(&ec->vdev->kobj, &ec_attr_group);
+}