[PATCH v6 09/11] mfd: cros_ec: Add convenience struct to define autodetectable CrOS EC subdevices

From: Enric Balletbo i Serra
Date: Fri Aug 23 2019 - 08:54:35 EST


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@xxxxxxxxxxxxx>
Acked-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Reviewed-by: Gwendal Grignou <gwendal@xxxxxxxxxxxx>
Tested-by: Gwendal Grignou <gwendal@xxxxxxxxxxxx>
Acked-for-MFD-by: Lee Jones <lee.jones@xxxxxxxxxx>
---

Changes in v6: None
Changes in v5: None
Changes in v4: None
Changes in v3:
- Use mfd_add_hotplug_devices helper (Gwendal)

Changes in v2: None

drivers/mfd/cros_ec_dev.c | 131 +++++++++++++++++++++-----------------
1 file changed, 73 insertions(+), 58 deletions(-)

diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c
index 31da038effc0..90eb02c56b77 100644
--- 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),
--
2.20.1