Merge tag 'chrome-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/olof/chrome-platform

Pull chrome platform updates from Olof Johansson:
 "Here's a set of updates to the Chrome OS platform drivers for this
  merge window.

  Main new things this cycle is:

   - Driver changes to expose the lightbar to users.  With this, you can
     make your own blinkenlights on Chromebook Pixels.

   - Changes in the way that the atmel_mxt trackpads are probed.  The
     laptop driver is trying to be smart and not instantiate the devices
     that don't answer to probe.  For the trackpad that can come up in
     two modes (bootloader or regular), this gets complicated since the
     driver already knows how to handle the two modes including the
     actual addresses used.  So now the laptop driver needs to know more
     too, instantiating the regular address even if the bootloader one
     is the probe that passed.

   - mfd driver improvements by Javier Martines Canillas, and a few
     bugfixes from him, kbuild and myself"

* tag 'chrome-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/olof/chrome-platform:
  platform/chrome: chromeos_laptop - instantiate Atmel at primary address
  platform/chrome: cros_ec_lpc - Depend on X86 || COMPILE_TEST
  platform/chrome: cros_ec_lpc - Include linux/io.h header file
  platform/chrome: fix platform_no_drv_owner.cocci warnings
  platform/chrome: cros_ec_lightbar - fix duplicate const warning
  platform/chrome: cros_ec_dev - fix Unknown escape '%' warning
  platform/chrome: Expose Chrome OS Lightbar to users
  platform/chrome: Create sysfs attributes for the ChromeOS EC
  mfd: cros_ec: Instantiate ChromeOS EC character device
  platform/chrome: Add Chrome OS EC userspace device interface
  platform/chrome: Add cros_ec_lpc driver for x86 devices
  mfd: cros_ec: Add char dev and virtual dev pointers
  mfd: cros_ec: Use fixed size arrays to transfer data with the EC

1 files changed, 367 insertions, 0 deletions

diff --git a/drivers/platform/chrome/cros_ec_lightbar.c b/drivers/platform/chrome/cros_ec_lightbar.c
new file mode 100644
index 000000000000..b4ff47a9069a
--- /dev/null
+++ b/drivers/platform/chrome/cros_ec_lightbar.c
@@ -0,0 +1,367 @@
+/*
+ * cros_ec_lightbar - expose the Chromebook Pixel lightbar to userspace
+ *
+ * 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_lightbar: " 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/sched.h>
+#include <linux/types.h>
+#include <linux/uaccess.h>
+
+#include "cros_ec_dev.h"
+
+/* Rate-limit the lightbar interface to prevent DoS. */
+static unsigned long lb_interval_jiffies = 50 * HZ / 1000;
+
+static ssize_t interval_msec_show(struct device *dev,
+                                  struct device_attribute *attr, char *buf)
+{
+        unsigned long msec = lb_interval_jiffies * 1000 / HZ;
+
+        return scnprintf(buf, PAGE_SIZE, "%lu\n", msec);
+}
+
+static ssize_t interval_msec_store(struct device *dev,
+                                   struct device_attribute *attr,
+                                   const char *buf, size_t count)
+{
+        unsigned long msec;
+
+        if (kstrtoul(buf, 0, &msec))
+                return -EINVAL;
+
+        lb_interval_jiffies = msec * HZ / 1000;
+
+        return count;
+}
+
+static DEFINE_MUTEX(lb_mutex);
+/* Return 0 if able to throttle correctly, error otherwise */
+static int lb_throttle(void)
+{
+        static unsigned long last_access;
+        unsigned long now, next_timeslot;
+        long delay;
+        int ret = 0;
+
+        mutex_lock(&lb_mutex);
+
+        now = jiffies;
+        next_timeslot = last_access + lb_interval_jiffies;
+
+        if (time_before(now, next_timeslot)) {
+                delay = (long)(next_timeslot) - (long)now;
+                set_current_state(TASK_INTERRUPTIBLE);
+                if (schedule_timeout(delay) > 0) {
+                        /* interrupted - just abort */
+                        ret = -EINTR;
+                        goto out;
+                }
+                now = jiffies;
+        }
+
+        last_access = now;
+out:
+        mutex_unlock(&lb_mutex);
+
+        return ret;
+}
+
+#define INIT_MSG(P, R) { \
+                .command = EC_CMD_LIGHTBAR_CMD, \
+                .outsize = sizeof(*P), \
+                .insize = sizeof(*R), \
+        }
+
+static int get_lightbar_version(struct cros_ec_device *ec,
+                                uint32_t *ver_ptr, uint32_t *flg_ptr)
+{
+        struct ec_params_lightbar *param;
+        struct ec_response_lightbar *resp;
+        struct cros_ec_command msg = INIT_MSG(param, resp);
+        int ret;
+
+        param = (struct ec_params_lightbar *)msg.outdata;
+        param->cmd = LIGHTBAR_CMD_VERSION;
+        ret = cros_ec_cmd_xfer(ec, &msg);
+        if (ret < 0)
+                return 0;
+
+        switch (msg.result) {
+        case EC_RES_INVALID_PARAM:
+                /* Pixel had no version command. */
+                if (ver_ptr)
+                        *ver_ptr = 0;
+                if (flg_ptr)
+                        *flg_ptr = 0;
+                return 1;
+
+        case EC_RES_SUCCESS:
+                resp = (struct ec_response_lightbar *)msg.indata;
+
+                /* Future devices w/lightbars should implement this command */
+                if (ver_ptr)
+                        *ver_ptr = resp->version.num;
+                if (flg_ptr)
+                        *flg_ptr = resp->version.flags;
+                return 1;
+        }
+
+        /* Anything else (ie, EC_RES_INVALID_COMMAND) - no lightbar */
+        return 0;
+}
+
+static ssize_t version_show(struct device *dev,
+                            struct device_attribute *attr, char *buf)
+{
+        uint32_t version, flags;
+        struct cros_ec_device *ec = dev_get_drvdata(dev);
+        int ret;
+
+        ret = lb_throttle();
+        if (ret)
+                return ret;
+
+        /* This should always succeed, because we check during init. */
+        if (!get_lightbar_version(ec, &version, &flags))
+                return -EIO;
+
+        return scnprintf(buf, PAGE_SIZE, "%d %d\n", version, flags);
+}
+
+static ssize_t brightness_store(struct device *dev,
+                                struct device_attribute *attr,
+                                const char *buf, size_t count)
+{
+        struct ec_params_lightbar *param;
+        struct ec_response_lightbar *resp;
+        struct cros_ec_command msg = INIT_MSG(param, resp);
+        int ret;
+        unsigned int val;
+        struct cros_ec_device *ec = dev_get_drvdata(dev);
+
+        if (kstrtouint(buf, 0, &val))
+                return -EINVAL;
+
+        param = (struct ec_params_lightbar *)msg.outdata;
+        param->cmd = LIGHTBAR_CMD_BRIGHTNESS;
+        param->brightness.num = val;
+        ret = lb_throttle();
+        if (ret)
+                return ret;
+
+        ret = cros_ec_cmd_xfer(ec, &msg);
+        if (ret < 0)
+                return ret;
+
+        if (msg.result != EC_RES_SUCCESS)
+                return -EINVAL;
+
+        return count;
+}
+
+
+/*
+ * We expect numbers, and we'll keep reading until we find them, skipping over
+ * any whitespace (sysfs guarantees that the input is null-terminated). Every
+ * four numbers are sent to the lightbar as <LED,R,G,B>. We fail at the first
+ * parsing error, if we don't parse any numbers, or if we have numbers left
+ * over.
+ */
+static ssize_t led_rgb_store(struct device *dev, struct device_attribute *attr,
+                             const char *buf, size_t count)
+{
+        struct ec_params_lightbar *param;
+        struct ec_response_lightbar *resp;
+        struct cros_ec_command msg = INIT_MSG(param, resp);
+        struct cros_ec_device *ec = dev_get_drvdata(dev);
+        unsigned int val[4];
+        int ret, i = 0, j = 0, ok = 0;
+
+        do {
+                /* Skip any whitespace */
+                while (*buf && isspace(*buf))
+                        buf++;
+
+                if (!*buf)
+                        break;
+
+                ret = sscanf(buf, "%i", &val[i++]);
+                if (ret == 0)
+                        return -EINVAL;
+
+                if (i == 4) {
+                        param = (struct ec_params_lightbar *)msg.outdata;
+                        param->cmd = LIGHTBAR_CMD_RGB;
+                        param->rgb.led = val[0];
+                        param->rgb.red = val[1];
+                        param->rgb.green = val[2];
+                        param->rgb.blue = val[3];
+                        /*
+                         * Throttle only the first of every four transactions,
+                         * so that the user can update all four LEDs at once.
+                         */
+                        if ((j++ % 4) == 0) {
+                                ret = lb_throttle();
+                                if (ret)
+                                        return ret;
+                        }
+
+                        ret = cros_ec_cmd_xfer(ec, &msg);
+                        if (ret < 0)
+                                return ret;
+
+                        if (msg.result != EC_RES_SUCCESS)
+                                return -EINVAL;
+
+                        i = 0;
+                        ok = 1;
+                }
+
+                /* Skip over the number we just read */
+                while (*buf && !isspace(*buf))
+                        buf++;
+
+        } while (*buf);
+
+        return (ok && i == 0) ? count : -EINVAL;
+}
+
+static char const *seqname[] = {
+        "ERROR", "S5", "S3", "S0", "S5S3", "S3S0",
+        "S0S3", "S3S5", "STOP", "RUN", "PULSE", "TEST", "KONAMI",
+};
+
+static ssize_t sequence_show(struct device *dev,
+                             struct device_attribute *attr, char *buf)
+{
+        struct ec_params_lightbar *param;
+        struct ec_response_lightbar *resp;
+        struct cros_ec_command msg = INIT_MSG(param, resp);
+        int ret;
+        struct cros_ec_device *ec = dev_get_drvdata(dev);
+
+        param = (struct ec_params_lightbar *)msg.outdata;
+        param->cmd = LIGHTBAR_CMD_GET_SEQ;
+        ret = lb_throttle();
+        if (ret)
+                return ret;
+
+        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_lightbar *)msg.indata;
+        if (resp->get_seq.num >= ARRAY_SIZE(seqname))
+                return scnprintf(buf, PAGE_SIZE, "%d\n", resp->get_seq.num);
+        else
+                return scnprintf(buf, PAGE_SIZE, "%s\n",
+                                 seqname[resp->get_seq.num]);
+}
+
+static ssize_t sequence_store(struct device *dev, struct device_attribute *attr,
+                              const char *buf, size_t count)
+{
+        struct ec_params_lightbar *param;
+        struct ec_response_lightbar *resp;
+        struct cros_ec_command msg = INIT_MSG(param, resp);
+        unsigned int num;
+        int ret, len;
+        struct cros_ec_device *ec = dev_get_drvdata(dev);
+
+        for (len = 0; len < count; len++)
+                if (!isalnum(buf[len]))
+                        break;
+
+        for (num = 0; num < ARRAY_SIZE(seqname); num++)
+                if (!strncasecmp(seqname[num], buf, len))
+                        break;
+
+        if (num >= ARRAY_SIZE(seqname)) {
+                ret = kstrtouint(buf, 0, &num);
+                if (ret)
+                        return ret;
+        }
+
+        param = (struct ec_params_lightbar *)msg.outdata;
+        param->cmd = LIGHTBAR_CMD_SEQ;
+        param->seq.num = num;
+        ret = lb_throttle();
+        if (ret)
+                return ret;
+
+        ret = cros_ec_cmd_xfer(ec, &msg);
+        if (ret < 0)
+                return ret;
+
+        if (msg.result != EC_RES_SUCCESS)
+                return -EINVAL;
+
+        return count;
+}
+
+/* Module initialization */
+
+static DEVICE_ATTR_RW(interval_msec);
+static DEVICE_ATTR_RO(version);
+static DEVICE_ATTR_WO(brightness);
+static DEVICE_ATTR_WO(led_rgb);
+static DEVICE_ATTR_RW(sequence);
+static struct attribute *__lb_cmds_attrs[] = {
+        &dev_attr_interval_msec.attr,
+        &dev_attr_version.attr,
+        &dev_attr_brightness.attr,
+        &dev_attr_led_rgb.attr,
+        &dev_attr_sequence.attr,
+        NULL,
+};
+static struct attribute_group lb_cmds_attr_group = {
+        .name = "lightbar",
+        .attrs = __lb_cmds_attrs,
+};
+
+void ec_dev_lightbar_init(struct cros_ec_device *ec)
+{
+        int ret = 0;
+
+        /* Only instantiate this stuff if the EC has a lightbar */
+        if (!get_lightbar_version(ec, NULL, NULL))
+                return;
+
+        ret = sysfs_create_group(&ec->vdev->kobj, &lb_cmds_attr_group);
+        if (ret)
+                pr_warn("sysfs_create_group() failed: %d\n", ret);
+}
+
+void ec_dev_lightbar_remove(struct cros_ec_device *ec)
+{
+        sysfs_remove_group(&ec->vdev->kobj, &lb_cmds_attr_group);
+}