From 572d3c6444979a6a49c6b464110563f578e8dece Mon Sep 17 00:00:00 2001 From: Brian Norris Date: Thu, 9 Feb 2017 18:03:57 -0800 Subject: [PATCH] HID: i2c-hid: support regulator power on/off On some boards, we need to enable a regulator before using the HID, and it's also nice to save power in suspend by disabling it. Support an optional "vdd-supply" and a companion initialization delay. Signed-off-by: Brian Norris Signed-off-by: Caesar Wang Acked-by: Benjamin Tissoires Reviewed-by: Dmitry Torokhov Cc: Jiri Kosina Cc: linux-input@vger.kernel.org Signed-off-by: Jiri Kosina --- drivers/hid/i2c-hid/i2c-hid.c | 42 +++++++++++++++++++++++++++++++++-- include/linux/i2c/i2c-hid.h | 6 +++++ 2 files changed, 46 insertions(+), 2 deletions(-) diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c index ea3c3546cef7..a3f6daf0886b 100644 --- a/drivers/hid/i2c-hid/i2c-hid.c +++ b/drivers/hid/i2c-hid/i2c-hid.c @@ -994,6 +994,11 @@ static int i2c_hid_of_probe(struct i2c_client *client, } pdata->hid_descriptor_address = val; + ret = of_property_read_u32(dev->of_node, "post-power-on-delay-ms", + &val); + if (!ret) + pdata->post_power_delay_ms = val; + return 0; } @@ -1053,6 +1058,24 @@ static int i2c_hid_probe(struct i2c_client *client, ihid->pdata = *platform_data; } + ihid->pdata.supply = devm_regulator_get(&client->dev, "vdd"); + if (IS_ERR(ihid->pdata.supply)) { + ret = PTR_ERR(ihid->pdata.supply); + if (ret != -EPROBE_DEFER) + dev_err(&client->dev, "Failed to get regulator: %d\n", + ret); + return ret; + } + + ret = regulator_enable(ihid->pdata.supply); + if (ret < 0) { + dev_err(&client->dev, "Failed to enable regulator: %d\n", + ret); + goto err; + } + if (ihid->pdata.post_power_delay_ms) + msleep(ihid->pdata.post_power_delay_ms); + i2c_set_clientdata(client, ihid); ihid->client = client; @@ -1068,7 +1091,7 @@ static int i2c_hid_probe(struct i2c_client *client, * real computation later. */ ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE); if (ret < 0) - goto err; + goto err_regulator; pm_runtime_get_noresume(&client->dev); pm_runtime_set_active(&client->dev); @@ -1125,6 +1148,9 @@ err_pm: pm_runtime_put_noidle(&client->dev); pm_runtime_disable(&client->dev); +err_regulator: + regulator_disable(ihid->pdata.supply); + err: i2c_hid_free_buffers(ihid); kfree(ihid); @@ -1149,6 +1175,8 @@ static int i2c_hid_remove(struct i2c_client *client) if (ihid->bufsize) i2c_hid_free_buffers(ihid); + regulator_disable(ihid->pdata.supply); + kfree(ihid); return 0; @@ -1199,6 +1227,10 @@ static int i2c_hid_suspend(struct device *dev) else hid_warn(hid, "Failed to enable irq wake: %d\n", wake_status); + } else { + ret = regulator_disable(ihid->pdata.supply); + if (ret < 0) + hid_warn(hid, "Failed to disable supply: %d\n", ret); } return 0; @@ -1212,7 +1244,13 @@ static int i2c_hid_resume(struct device *dev) struct hid_device *hid = ihid->hid; int wake_status; - if (device_may_wakeup(&client->dev) && ihid->irq_wake_enabled) { + if (!device_may_wakeup(&client->dev)) { + ret = regulator_enable(ihid->pdata.supply); + if (ret < 0) + hid_warn(hid, "Failed to enable supply: %d\n", ret); + if (ihid->pdata.post_power_delay_ms) + msleep(ihid->pdata.post_power_delay_ms); + } else if (ihid->irq_wake_enabled) { wake_status = disable_irq_wake(client->irq); if (!wake_status) ihid->irq_wake_enabled = false; diff --git a/include/linux/i2c/i2c-hid.h b/include/linux/i2c/i2c-hid.h index 7aa901d92058..1fb088239d12 100644 --- a/include/linux/i2c/i2c-hid.h +++ b/include/linux/i2c/i2c-hid.h @@ -14,9 +14,13 @@ #include +struct regulator; + /** * struct i2chid_platform_data - used by hid over i2c implementation. * @hid_descriptor_address: i2c register where the HID descriptor is stored. + * @supply: regulator for powering on the device. + * @post_power_delay_ms: delay after powering on before device is usable. * * Note that it is the responsibility of the platform driver (or the acpi 5.0 * driver, or the flattened device tree) to setup the irq related to the gpio in @@ -31,6 +35,8 @@ */ struct i2c_hid_platform_data { u16 hid_descriptor_address; + struct regulator *supply; + int post_power_delay_ms; }; #endif /* __LINUX_I2C_HID_H */ -- 2.20.1