With this patch, the cros_ec_ctl driver will register the legacy accelerometer driver (named cros_ec_accel_legacy) if it fails to register sensors through the usual path cros_ec_sensors_register(). This legacy device is present on Chromebook devices with older EC firmware only supporting deprecated EC commands: - Glimmer based devices [Intel SOC using LPC transport] - Veyron minnie devices [ARM SOC using SPI transport]
Tested-by: Gwendal Grignou <[email protected]> Signed-off-by: Enric Balletbo i Serra <[email protected]> Reviewed-by: Andy Shevchenko <[email protected]> Signed-off-by: Gwendal Grignou <[email protected]> --- Changes in v6: - Remove .id field in mfd_cell, PLATFORM_DEVID_AUTO is set to auto assign ids. - Add support for ARM devices with older EC. Changes in v5: - Remove unnecessary white lines. Changes in v4: - [5/8] Nit: EC -> ECs (Lee Jones) - [5/8] Statically define cros_ec_accel_legacy_cells (Lee Jones) Changes in v3: - [5/8] Add the Reviewed-by Andy Shevchenko. Changes in v2: - [5/8] Add the Reviewed-by Gwendal. drivers/mfd/cros_ec_dev.c | 69 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c index 54a58df571b6..c2156b6086eb 100644 --- a/drivers/mfd/cros_ec_dev.c +++ b/drivers/mfd/cros_ec_dev.c @@ -376,6 +376,72 @@ static void cros_ec_sensors_register(struct cros_ec_dev *ec) kfree(msg); } +static struct cros_ec_sensor_platform sensor_platforms[] = { + { .sensor_num = 0 }, + { .sensor_num = 1 } +}; + +static const struct mfd_cell cros_ec_accel_legacy_cells[] = { + { + .name = "cros-ec-accel-legacy", + .platform_data = &sensor_platforms[0], + .pdata_size = sizeof(struct cros_ec_sensor_platform), + }, + { + .name = "cros-ec-accel-legacy", + .platform_data = &sensor_platforms[1], + .pdata_size = sizeof(struct cros_ec_sensor_platform), + } +}; + +static void cros_ec_accel_legacy_register(struct cros_ec_dev *ec) +{ + struct cros_ec_device *ec_dev = ec->ec_dev; + u8 status; + int ret; + + /* + * ECs that need legacy support are the main EC, directly connected to + * the AP. + */ + if (ec->cmd_offset != 0) + return; + + /* + * Check if EC supports direct memory reads and if EC has + * accelerometers. + */ + if (ec_dev->cmd_readmem) { + ret = ec_dev->cmd_readmem(ec_dev, EC_MEMMAP_ACC_STATUS, 1, + &status); + if (ret < 0) { + dev_warn(ec->dev, "EC direct read error.\n"); + return; + } + + /* Check if EC has accelerometers. */ + if (!(status & EC_MEMMAP_ACC_STATUS_PRESENCE_BIT)) { + dev_info(ec->dev, "EC does not have accelerometers.\n"); + return; + } + } + + /* + * The device may still support accelerometers: + * it would be an older ARM based device that do not suppor the + * EC_CMD_GET_FEATURES command. + * + * Register 2 accelerometers, we will fail in the IIO driver if there + * are no sensors. + */ + ret = mfd_add_devices(ec->dev, PLATFORM_DEVID_AUTO, + cros_ec_accel_legacy_cells, + ARRAY_SIZE(cros_ec_accel_legacy_cells), + NULL, 0, NULL); + if (ret) + dev_err(ec_dev->dev, "failed to add EC sensors\n"); +} + static const struct mfd_cell cros_ec_cec_cells[] = { { .name = "cros-ec-cec" } }; @@ -471,6 +537,9 @@ static int ec_device_probe(struct platform_device *pdev) /* check whether this EC is a sensor hub. */ if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE)) cros_ec_sensors_register(ec); + else + /* 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)) { -- 2.22.0.rc1.257.g3120a18244-goog
