Re: [PATCH 2/2] HID: i2c-hid: support the regulator
flat view
From: Benjamin Tissoires <hidden>
Date: 2016-09-14 07:36:21
Also in:
linux-rockchip, lkml
On Sep 05 2016 or thereabouts, Caesar Wang wrote:
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From: Brian Norris <briannorris@chromium.org> In order to allow supporting the HID based devices that need power on/off the regulator. We try to get a power-supply property from the device tree. Signed-off-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Caesar Wang <redacted> Cc: Jiri Kosina <jikos@kernel.org> Cc: linux-input@vger.kernel.org --- drivers/hid/i2c-hid/i2c-hid.c | 31 ++++++++++++++++++++++++++++++- 1 file changed, 30 insertions(+), 1 deletion(-)diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c index b3ec4f2..07cc7aa 100644 --- a/drivers/hid/i2c-hid/i2c-hid.c +++ b/drivers/hid/i2c-hid/i2c-hid.c@@ -38,6 +38,7 @@ #include <linux/acpi.h> #include <linux/of.h> #include <linux/gpio/consumer.h> +#include <linux/regulator/consumer.h> #include <linux/i2c/i2c-hid.h>@@ -152,6 +153,7 @@ struct i2c_hid { bool irq_wake_enabled; struct mutex reset_lock; + struct regulator *supply; }; static int __i2c_hid_command(struct i2c_client *client,@@ -968,6 +970,21 @@ static int i2c_hid_probe(struct i2c_client *client, if (!ihid) return -ENOMEM; + ihid->supply = devm_regulator_get(&client->dev, "power"); + if (IS_ERR(ihid->supply)) {
I am not familiar with regulators, but what if (like 99% of the available i2c-hid devices) there is no regulator attached to the device? Will the pointer be null? Will there be a dummy regulator? It seems at first sight that you are adding a requirement on the devices which is not part of the spec, and which will break every existing systems but yours. Again, I might be wrong, so please provide more information. Cheers, Benjamin
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+ ret = PTR_ERR(ihid->supply); + dev_err(&client->dev, "Failed to get power regulator: %d\n", + ret); + return ret; + } + + ret = regulator_enable(ihid->supply); + if (ret < 0) { + dev_err(&client->dev, "Failed to enable power regulator: %d\n", + ret); + return ret; + } + if (client->dev.of_node) { ret = i2c_hid_of_probe(client, &ihid->pdata); if (ret)@@ -1100,6 +1117,8 @@ static int i2c_hid_remove(struct i2c_client *client) if (ihid->desc) gpiod_put(ihid->desc); + regulator_disable(ihid->supply); + kfree(ihid); acpi_dev_remove_driver_gpios(ACPI_COMPANION(&client->dev));@@ -1152,6 +1171,11 @@ 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->supply); + if (ret < 0) + hid_warn(hid, "Failed to disable power supply: %d\n", + ret); } return 0;@@ -1165,7 +1189,12 @@ 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->supply); + if (ret < 0) + hid_warn(hid, "Failed to enable power supply: %d\n", + ret); + } else if (ihid->irq_wake_enabled) { wake_status = disable_irq_wake(ihid->irq); if (!wake_status) ihid->irq_wake_enabled = false;-- 1.9.1