[PATCH] cros_ec: instantiate properly Intel ISH MCU device

From: Rushikesh S Kadam
Date: Sun Feb 24 2019 - 04:14:45 EST


Intel Integrated Sensor Hub (ISH) is also a MCU running EC
having feature bit EC_FEATURE_ISH. Instantiate it as a special
CrOS EC device with device name 'cros_ish'.

Signed-off-by: Rushikesh S Kadam <rushikesh.s.kadam@xxxxxxxxx>
---
drivers/mfd/cros_ec_dev.c | 10 ++++++++++
include/linux/mfd/cros_ec.h | 1 +
include/linux/mfd/cros_ec_commands.h | 2 ++
3 files changed, 13 insertions(+)

diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c
index 2d0fee4..be499b8 100644
--- a/drivers/mfd/cros_ec_dev.c
+++ b/drivers/mfd/cros_ec_dev.c
@@ -414,6 +414,16 @@ static int ec_device_probe(struct platform_device *pdev)
device_initialize(&ec->class_dev);
cdev_init(&ec->cdev, &fops);

+ /* check whether this is actually a Intel ISH rather than an EC */
+ if (cros_ec_check_features(ec, EC_FEATURE_ISH)) {
+ dev_info(dev, "Intel ISH MCU detected.\n");
+ /*
+ * Help userspace differentiating ECs from ISH MCU,
+ * regardless of the probing order.
+ */
+ ec_platform->ec_name = CROS_EC_DEV_ISH_NAME;
+ }
+
/*
* Add the class device
* Link to the character device for creating the /dev entry
diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h
index de8b588..00c5765 100644
--- a/include/linux/mfd/cros_ec.h
+++ b/include/linux/mfd/cros_ec.h
@@ -24,6 +24,7 @@

#define CROS_EC_DEV_NAME "cros_ec"
#define CROS_EC_DEV_PD_NAME "cros_pd"
+#define CROS_EC_DEV_ISH_NAME "cros_ish"

/*
* The EC is unresponsive for a time after a reboot command. Add a
diff --git a/include/linux/mfd/cros_ec_commands.h b/include/linux/mfd/cros_ec_commands.h
index fc91082..9276c3c 100644
--- a/include/linux/mfd/cros_ec_commands.h
+++ b/include/linux/mfd/cros_ec_commands.h
@@ -856,6 +856,8 @@ enum ec_feature_code {
EC_FEATURE_RTC = 27,
/* EC supports CEC commands */
EC_FEATURE_CEC = 35,
+ /* The MCU is an Intel Integrated Sensor Hub */
+ EC_FEATURE_ISH = 40,
};

#define EC_FEATURE_MASK_0(event_code) (1UL << (event_code % 32))
--
1.9.1