mfd: cros_ec: Add convenience struct to define autodetectable CrOS EC subdevices

The CrOS EC is gaining lots of subdevices that are autodetectable by
sending the EC_FEATURE_GET_CMD, it takes fair amount of boiler plate
code to add those devices. So, add a struct that can be used to quickly
add new subdevices without having to duplicate code.

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Tested-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c
index 31da038..90eb02c 100644 (file)
--- a/drivers/mfd/cros_ec_dev.c
+++ b/drivers/mfd/cros_ec_dev.c
@@ -35,6 +35,18 @@ struct cros_feature_to_name {
        const char *desc;
 };
 
+/**
+ * cros_feature_to_cells - CrOS feature id to mfd cells association.
+ * @id: The feature identifier.
+ * @mfd_cells: Pointer to the array of mfd cells that needs to be added.
+ * @num_cells: Number of mfd cells into the array.
+ */
+struct cros_feature_to_cells {
+       unsigned int id;
+       const struct mfd_cell *mfd_cells;
+       unsigned int num_cells;
+};
+
 static const struct cros_feature_to_name cros_mcu_devices[] = {
        {
                .id     = EC_FEATURE_FINGERPRINT,
@@ -58,6 +70,48 @@ static const struct cros_feature_to_name cros_mcu_devices[] = {
        },
 };
 
+static const struct mfd_cell cros_ec_cec_cells[] = {
+       { .name = "cros-ec-cec", },
+};
+
+static const struct mfd_cell cros_ec_rtc_cells[] = {
+       { .name = "cros-ec-rtc", },
+};
+
+static const struct mfd_cell cros_usbpd_charger_cells[] = {
+       { .name = "cros-usbpd-charger", },
+       { .name = "cros-usbpd-logger", },
+};
+
+static const struct cros_feature_to_cells cros_subdevices[] = {
+       {
+               .id             = EC_FEATURE_CEC,
+               .mfd_cells      = cros_ec_cec_cells,
+               .num_cells      = ARRAY_SIZE(cros_ec_cec_cells),
+       },
+       {
+               .id             = EC_FEATURE_RTC,
+               .mfd_cells      = cros_ec_rtc_cells,
+               .num_cells      = ARRAY_SIZE(cros_ec_rtc_cells),
+       },
+       {
+               .id             = EC_FEATURE_USB_PD,
+               .mfd_cells      = cros_usbpd_charger_cells,
+               .num_cells      = ARRAY_SIZE(cros_usbpd_charger_cells),
+       },
+};
+
+static const struct mfd_cell cros_ec_platform_cells[] = {
+       { .name = "cros-ec-chardev", },
+       { .name = "cros-ec-debugfs", },
+       { .name = "cros-ec-lightbar", },
+       { .name = "cros-ec-sysfs", },
+};
+
+static const struct mfd_cell cros_ec_vbc_cells[] = {
+       { .name = "cros-ec-vbc", }
+};
+
 static int cros_ec_check_features(struct cros_ec_dev *ec, int feature)
 {
        struct cros_ec_command *msg;
@@ -283,30 +337,6 @@ static void cros_ec_accel_legacy_register(struct cros_ec_dev *ec)
                dev_err(ec_dev->dev, "failed to add EC sensors\n");
 }
 
-static const struct mfd_cell cros_ec_cec_cells[] = {
-       { .name = "cros-ec-cec" }
-};
-
-static const struct mfd_cell cros_ec_rtc_cells[] = {
-       { .name = "cros-ec-rtc" }
-};
-
-static const struct mfd_cell cros_usbpd_charger_cells[] = {
-       { .name = "cros-usbpd-charger" },
-       { .name = "cros-usbpd-logger" },
-};
-
-static const struct mfd_cell cros_ec_platform_cells[] = {
-       { .name = "cros-ec-chardev" },
-       { .name = "cros-ec-debugfs" },
-       { .name = "cros-ec-lightbar" },
-       { .name = "cros-ec-sysfs" },
-};
-
-static const struct mfd_cell cros_ec_vbc_cells[] = {
-       { .name = "cros-ec-vbc" }
-};
-
 static int ec_device_probe(struct platform_device *pdev)
 {
        int retval = -ENOMEM;
@@ -368,42 +398,27 @@ static int ec_device_probe(struct platform_device *pdev)
                /* Workaroud for older EC firmware */
                cros_ec_accel_legacy_register(ec);
 
-       /* Check whether this EC instance has CEC host command support */
-       if (cros_ec_check_features(ec, EC_FEATURE_CEC)) {
-               retval = mfd_add_devices(ec->dev, PLATFORM_DEVID_AUTO,
-                                        cros_ec_cec_cells,
-                                        ARRAY_SIZE(cros_ec_cec_cells),
-                                        NULL, 0, NULL);
-               if (retval)
-                       dev_err(ec->dev,
-                               "failed to add cros-ec-cec device: %d\n",
-                               retval);
-       }
-
-       /* Check whether this EC instance has RTC host command support */
-       if (cros_ec_check_features(ec, EC_FEATURE_RTC)) {
-               retval = mfd_add_devices(ec->dev, PLATFORM_DEVID_AUTO,
-                                        cros_ec_rtc_cells,
-                                        ARRAY_SIZE(cros_ec_rtc_cells),
-                                        NULL, 0, NULL);
-               if (retval)
-                       dev_err(ec->dev,
-                               "failed to add cros-ec-rtc device: %d\n",
-                               retval);
-       }
-
-       /* Check whether this EC instance has the PD charge manager */
-       if (cros_ec_check_features(ec, EC_FEATURE_USB_PD)) {
-               retval = mfd_add_devices(ec->dev, PLATFORM_DEVID_AUTO,
-                                        cros_usbpd_charger_cells,
-                                        ARRAY_SIZE(cros_usbpd_charger_cells),
-                                        NULL, 0, NULL);
-               if (retval)
-                       dev_err(ec->dev,
-                               "failed to add cros-usbpd-charger device: %d\n",
-                               retval);
+       /*
+        * The following subdevices can be detected by sending the
+        * EC_FEATURE_GET_CMD Embedded Controller device.
+        */
+       for (i = 0; i < ARRAY_SIZE(cros_subdevices); i++) {
+               if (cros_ec_check_features(ec, cros_subdevices[i].id)) {
+                       retval = mfd_add_hotplug_devices(ec->dev,
+                                               cros_subdevices[i].mfd_cells,
+                                               cros_subdevices[i].num_cells);
+                       if (retval)
+                               dev_err(ec->dev,
+                                       "failed to add %s subdevice: %d\n",
+                                       cros_subdevices[i].mfd_cells->name,
+                                       retval);
+               }
        }
 
+       /*
+        * The following subdevices cannot be detected by sending the
+        * EC_FEATURE_GET_CMD to the Embedded Controller device.
+        */
        retval = mfd_add_devices(ec->dev, PLATFORM_DEVID_AUTO,
                                 cros_ec_platform_cells,
                                 ARRAY_SIZE(cros_ec_platform_cells),