[PATCH v6 08/11] mfd: cros_ec: Add convenience struct to define dedicated CrOS EC MCUs

From: Enric Balletbo i Serra
Date: Fri Aug 23 2019 - 08:54:31 EST


With the increasing use of dedicated CrOS EC MCUs, it takes a fair amount
of boiler plate code to add those devices, add a struct that can be used
to specify a dedicated CrOS EC MCU so we can just add a new item to it to
define a new dedicated MCU.

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
Acked-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Reviewed-by: Gwendal Grignou <gwendal@xxxxxxxxxxxx>
Tested-by: Gwendal Grignou <gwendal@xxxxxxxxxxxx>
---

Changes in v6:
- Add a break statement once the MCU type has been determined (Lee Jones)

Changes in v5: None
Changes in v4: None
Changes in v3: None
Changes in v2: None

drivers/mfd/cros_ec_dev.c | 88 ++++++++++++++++++++++-----------------
1 file changed, 49 insertions(+), 39 deletions(-)

diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c
index 148f39c79f41..31da038effc0 100644
--- a/drivers/mfd/cros_ec_dev.c
+++ b/drivers/mfd/cros_ec_dev.c
@@ -23,6 +23,41 @@ static struct class cros_class = {
.name = "chromeos",
};

+/**
+ * cros_feature_to_name - CrOS feature id to name/short description.
+ * @id: The feature identifier.
+ * @name: Device name associated with the feature id.
+ * @desc: Short name that will be displayed.
+ */
+struct cros_feature_to_name {
+ unsigned int id;
+ const char *name;
+ const char *desc;
+};
+
+static const struct cros_feature_to_name cros_mcu_devices[] = {
+ {
+ .id = EC_FEATURE_FINGERPRINT,
+ .name = CROS_EC_DEV_FP_NAME,
+ .desc = "Fingerprint",
+ },
+ {
+ .id = EC_FEATURE_ISH,
+ .name = CROS_EC_DEV_ISH_NAME,
+ .desc = "Integrated Sensor Hub",
+ },
+ {
+ .id = EC_FEATURE_SCP,
+ .name = CROS_EC_DEV_SCP_NAME,
+ .desc = "System Control Processor",
+ },
+ {
+ .id = EC_FEATURE_TOUCHPAD,
+ .name = CROS_EC_DEV_TP_NAME,
+ .desc = "Touchpad",
+ },
+};
+
static int cros_ec_check_features(struct cros_ec_dev *ec, int feature)
{
struct cros_ec_command *msg;
@@ -279,6 +314,7 @@ static int ec_device_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct cros_ec_platform *ec_platform = dev_get_platdata(dev);
struct cros_ec_dev *ec = kzalloc(sizeof(*ec), GFP_KERNEL);
+ int i;

if (!ec)
return retval;
@@ -291,47 +327,21 @@ static int ec_device_probe(struct platform_device *pdev)
ec->features[1] = -1U; /* Not cached yet */
device_initialize(&ec->class_dev);

- /* Check whether this is actually a Fingerprint MCU rather than an EC */
- if (cros_ec_check_features(ec, EC_FEATURE_FINGERPRINT)) {
- dev_info(dev, "CrOS Fingerprint MCU detected.\n");
+ for (i = 0; i < ARRAY_SIZE(cros_mcu_devices); i++) {
/*
- * Help userspace differentiating ECs from FP MCU,
- * regardless of the probing order.
+ * Check whether this is actually a dedicated MCU rather
+ * than an standard EC.
*/
- ec_platform->ec_name = CROS_EC_DEV_FP_NAME;
- }
-
- /*
- * Check whether this is actually an Integrated Sensor Hub (ISH)
- * rather than an EC.
- */
- if (cros_ec_check_features(ec, EC_FEATURE_ISH)) {
- dev_info(dev, "CrOS 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;
- }
-
- /* Check whether this is actually a Touchpad MCU rather than an EC */
- if (cros_ec_check_features(ec, EC_FEATURE_TOUCHPAD)) {
- dev_info(dev, "CrOS Touchpad MCU detected.\n");
- /*
- * Help userspace differentiating ECs from TP MCU,
- * regardless of the probing order.
- */
- ec_platform->ec_name = CROS_EC_DEV_TP_NAME;
- }
-
- /* Check whether this is actually a SCP rather than an EC. */
- if (cros_ec_check_features(ec, EC_FEATURE_SCP)) {
- dev_info(dev, "CrOS SCP MCU detected.\n");
- /*
- * Help userspace differentiating ECs from SCP,
- * regardless of the probing order.
- */
- ec_platform->ec_name = CROS_EC_DEV_SCP_NAME;
+ if (cros_ec_check_features(ec, cros_mcu_devices[i].id)) {
+ dev_info(dev, "CrOS %s MCU detected\n",
+ cros_mcu_devices[i].desc);
+ /*
+ * Help userspace differentiating ECs from other MCU,
+ * regardless of the probing order.
+ */
+ ec_platform->ec_name = cros_mcu_devices[i].name;
+ break;
+ }
}

/*
--
2.20.1