platform/chrome: cros_ec_lightbar - Add lightbar program feature to sysfs

Add a program feature so we can upload and run programs for lightbar
sequences. We should be able to use this to shift sequences out of the
EC and save space there.

  $ cat <suitable program bin> > /sys/devices/.../cros_ec/program
  $ echo program > /sys/devices/.../cros_ec/sequence

Signed-off-by: Eric Caruso <ejcaruso@chromium.org>
Signed-off-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Benson Leung <bleung@chromium.org>

diff --git a/drivers/platform/chrome/cros_ec_lightbar.c b/drivers/platform/chrome/cros_ec_lightbar.c
index 8df3d44..2667505 100644 (file)
--- a/drivers/platform/chrome/cros_ec_lightbar.c
+++ b/drivers/platform/chrome/cros_ec_lightbar.c
@@ -295,7 +295,8 @@ exit:
 
 static char const *seqname[] = {
        "ERROR", "S5", "S3", "S0", "S5S3", "S3S0",
-       "S0S3", "S3S5", "STOP", "RUN", "PULSE", "TEST", "KONAMI",
+       "S0S3", "S3S5", "STOP", "RUN", "KONAMI",
+       "TAP", "PROGRAM",
 };
 
 static ssize_t sequence_show(struct device *dev,
@@ -390,6 +391,69 @@ exit:
        return ret;
 }
 
+static ssize_t program_store(struct device *dev, struct device_attribute *attr,
+                            const char *buf, size_t count)
+{
+       int extra_bytes, max_size, ret;
+       struct ec_params_lightbar *param;
+       struct cros_ec_command *msg;
+       struct cros_ec_dev *ec = container_of(dev, struct cros_ec_dev,
+                                             class_dev);
+
+       /*
+        * We might need to reject the program for size reasons. The EC
+        * enforces a maximum program size, but we also don't want to try
+        * and send a program that is too big for the protocol. In order
+        * to ensure the latter, we also need to ensure we have extra bytes
+        * to represent the rest of the packet.
+        */
+       extra_bytes = sizeof(*param) - sizeof(param->set_program.data);
+       max_size = min(EC_LB_PROG_LEN, ec->ec_dev->max_request - extra_bytes);
+       if (count > max_size) {
+               dev_err(dev, "Program is %u bytes, too long to send (max: %u)",
+                       (unsigned int)count, max_size);
+
+               return -EINVAL;
+       }
+
+       msg = alloc_lightbar_cmd_msg(ec);
+       if (!msg)
+               return -ENOMEM;
+
+       ret = lb_throttle();
+       if (ret)
+               goto exit;
+
+       dev_info(dev, "Copying %zu byte program to EC", count);
+
+       param = (struct ec_params_lightbar *)msg->data;
+       param->cmd = LIGHTBAR_CMD_SET_PROGRAM;
+
+       param->set_program.size = count;
+       memcpy(param->set_program.data, buf, count);
+
+       /*
+        * We need to set the message size manually or else it will use
+        * EC_LB_PROG_LEN. This might be too long, and the program
+        * is unlikely to use all of the space.
+        */
+       msg->outsize = count + extra_bytes;
+
+       ret = cros_ec_cmd_xfer(ec->ec_dev, msg);
+       if (ret < 0)
+               goto exit;
+       if (msg->result != EC_RES_SUCCESS) {
+               ret = -EINVAL;
+               goto exit;
+       }
+
+       ret = count;
+exit:
+       kfree(msg);
+
+       return ret;
+}
+
 /* Module initialization */
 
 static DEVICE_ATTR_RW(interval_msec);
@@ -397,12 +461,15 @@ static DEVICE_ATTR_RO(version);
 static DEVICE_ATTR_WO(brightness);
 static DEVICE_ATTR_WO(led_rgb);
 static DEVICE_ATTR_RW(sequence);
+static DEVICE_ATTR_WO(program);
+
 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,
+       &dev_attr_program.attr,
        NULL,
 };
 

diff --git a/include/linux/mfd/cros_ec_commands.h b/include/linux/mfd/cros_ec_commands.h
index 1b19e42..dbea580 100644 (file)
--- a/include/linux/mfd/cros_ec_commands.h
+++ b/include/linux/mfd/cros_ec_commands.h
@@ -1162,6 +1162,13 @@ struct lightbar_params_v1 {
        struct rgb_s color[8];                  /* 0-3 are Google colors */
 } __packed;
 
+/* Lightbar program */
+#define EC_LB_PROG_LEN 192
+struct lightbar_program {
+       uint8_t size;
+       uint8_t data[EC_LB_PROG_LEN];
+};
+
 struct ec_params_lightbar {
        uint8_t cmd;                  /* Command (see enum lightbar_command) */
        union {
@@ -1188,6 +1195,7 @@ struct ec_params_lightbar {
 
                struct lightbar_params_v0 set_params_v0;
                struct lightbar_params_v1 set_params_v1;
+               struct lightbar_program set_program;
        };
 } __packed;
 
@@ -1220,7 +1228,8 @@ struct ec_response_lightbar {
                struct {
                        /* no return params */
                } off, on, init, set_brightness, seq, reg, set_rgb,
-                       demo, set_params_v0, set_params_v1;
+                       demo, set_params_v0, set_params_v1,
+                       set_program;
        };
 } __packed;
 
@@ -1244,6 +1253,7 @@ enum lightbar_command {
        LIGHTBAR_CMD_GET_DEMO = 15,
        LIGHTBAR_CMD_GET_PARAMS_V1 = 16,
        LIGHTBAR_CMD_SET_PARAMS_V1 = 17,
+       LIGHTBAR_CMD_SET_PROGRAM = 18,
        LIGHTBAR_NUM_CMDS
 };