On Wed, Oct 16, 2019 at 5:12 PM Kai-Heng Feng
<kai.heng.feng@xxxxxxxxxxxxx> wrote:
>
> Runtime power management in i2c-hid brings lots of issues, such as:
> - When transitioning from display manager to desktop session, i2c-hid
> was closed and opened, so the device was set to SLEEP and ON in a short
> period. Vendors confirmed that their devices can't handle fast ON/SLEEP
> command because Windows doesn't have this behavior.
>
> - When rebooting, i2c-hid was closed, and the driver core put the device
> back to full power before shutdown. This behavior also triggers a quick
> SLEEP and ON commands that some devices can't handle, renders an
> unusable touchpad after reboot.
>
> - Most importantly, my power meter reports little to none energy saving
> when i2c-hid is runtime suspended.
>
> So let's remove runtime power management since there is no actual
> benefit.
>
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
> ---
> v2:
> - Remove unused label and wording change.
Thanks!
v2 now applied to for-5.4/upstream-fixes
(with Hans' acked-by from the v1 kept)
Cheers,
Benjamin
>
> drivers/hid/i2c-hid/i2c-hid-core.c | 118 ++---------------------------
> 1 file changed, 7 insertions(+), 111 deletions(-)
>
> diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
> index 2a7c6e33bb1c..d9c55e30f986 100644
> --- a/drivers/hid/i2c-hid/i2c-hid-core.c
> +++ b/drivers/hid/i2c-hid/i2c-hid-core.c
> @@ -26,7 +26,6 @@
> #include <linux/delay.h>
> #include <linux/slab.h>
> #include <linux/pm.h>
> -#include <linux/pm_runtime.h>
> #include <linux/device.h>
> #include <linux/wait.h>
> #include <linux/err.h>
> @@ -48,8 +47,6 @@
> /* quirks to control the device */
> #define I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV BIT(0)
> #define I2C_HID_QUIRK_NO_IRQ_AFTER_RESET BIT(1)
> -#define I2C_HID_QUIRK_NO_RUNTIME_PM BIT(2)
> -#define I2C_HID_QUIRK_DELAY_AFTER_SLEEP BIT(3)
> #define I2C_HID_QUIRK_BOGUS_IRQ BIT(4)
>
> /* flags */
> @@ -172,14 +169,7 @@ static const struct i2c_hid_quirks {
> { USB_VENDOR_ID_WEIDA, HID_ANY_ID,
> I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV },
> { I2C_VENDOR_ID_HANTICK, I2C_PRODUCT_ID_HANTICK_5288,
> - I2C_HID_QUIRK_NO_IRQ_AFTER_RESET |
> - I2C_HID_QUIRK_NO_RUNTIME_PM },
> - { I2C_VENDOR_ID_RAYDIUM, I2C_PRODUCT_ID_RAYDIUM_4B33,
> - I2C_HID_QUIRK_DELAY_AFTER_SLEEP },
> - { USB_VENDOR_ID_LG, I2C_DEVICE_ID_LG_8001,
> - I2C_HID_QUIRK_NO_RUNTIME_PM },
> - { I2C_VENDOR_ID_GOODIX, I2C_DEVICE_ID_GOODIX_01F0,
> - I2C_HID_QUIRK_NO_RUNTIME_PM },
> + I2C_HID_QUIRK_NO_IRQ_AFTER_RESET },
> { USB_VENDOR_ID_ELAN, HID_ANY_ID,
> I2C_HID_QUIRK_BOGUS_IRQ },
> { 0, 0 }
> @@ -397,7 +387,6 @@ static int i2c_hid_set_power(struct i2c_client *client, int power_state)
> {
> struct i2c_hid *ihid = i2c_get_clientdata(client);
> int ret;
> - unsigned long now, delay;
>
> i2c_hid_dbg(ihid, "%s\n", __func__);
>
> @@ -415,22 +404,9 @@ static int i2c_hid_set_power(struct i2c_client *client, int power_state)
> goto set_pwr_exit;
> }
>
> - if (ihid->quirks & I2C_HID_QUIRK_DELAY_AFTER_SLEEP &&
> - power_state == I2C_HID_PWR_ON) {
> - now = jiffies;
> - if (time_after(ihid->sleep_delay, now)) {
> - delay = jiffies_to_usecs(ihid->sleep_delay - now);
> - usleep_range(delay, delay + 1);
> - }
> - }
> -
> ret = __i2c_hid_command(client, &hid_set_power_cmd, power_state,
> 0, NULL, 0, NULL, 0);
>
> - if (ihid->quirks & I2C_HID_QUIRK_DELAY_AFTER_SLEEP &&
> - power_state == I2C_HID_PWR_SLEEP)
> - ihid->sleep_delay = jiffies + msecs_to_jiffies(20);
> -
> if (ret)
> dev_err(&client->dev, "failed to change power setting.\n");
>
> @@ -791,11 +767,6 @@ static int i2c_hid_open(struct hid_device *hid)
> {
> struct i2c_client *client = hid->driver_data;
> struct i2c_hid *ihid = i2c_get_clientdata(client);
> - int ret = 0;
> -
> - ret = pm_runtime_get_sync(&client->dev);
> - if (ret < 0)
> - return ret;
>
> set_bit(I2C_HID_STARTED, &ihid->flags);
> return 0;
> @@ -807,27 +778,6 @@ static void i2c_hid_close(struct hid_device *hid)
> struct i2c_hid *ihid = i2c_get_clientdata(client);
>
> clear_bit(I2C_HID_STARTED, &ihid->flags);
> -
> - /* Save some power */
> - pm_runtime_put(&client->dev);
> -}
> -
> -static int i2c_hid_power(struct hid_device *hid, int lvl)
> -{
> - struct i2c_client *client = hid->driver_data;
> - struct i2c_hid *ihid = i2c_get_clientdata(client);
> -
> - i2c_hid_dbg(ihid, "%s lvl:%d\n", __func__, lvl);
> -
> - switch (lvl) {
> - case PM_HINT_FULLON:
> - pm_runtime_get_sync(&client->dev);
> - break;
> - case PM_HINT_NORMAL:
> - pm_runtime_put(&client->dev);
> - break;
> - }
> - return 0;
> }
>
> struct hid_ll_driver i2c_hid_ll_driver = {
> @@ -836,7 +786,6 @@ struct hid_ll_driver i2c_hid_ll_driver = {
> .stop = i2c_hid_stop,
> .open = i2c_hid_open,
> .close = i2c_hid_close,
> - .power = i2c_hid_power,
> .output_report = i2c_hid_output_report,
> .raw_request = i2c_hid_raw_request,
> };
> @@ -1104,9 +1053,6 @@ static int i2c_hid_probe(struct i2c_client *client,
>
> i2c_hid_acpi_fix_up_power(&client->dev);
>
> - pm_runtime_get_noresume(&client->dev);
> - pm_runtime_set_active(&client->dev);
> - pm_runtime_enable(&client->dev);
> device_enable_async_suspend(&client->dev);
>
> /* Make sure there is something at this address */
> @@ -1114,16 +1060,16 @@ static int i2c_hid_probe(struct i2c_client *client,
> if (ret < 0) {
> dev_dbg(&client->dev, "nothing at this address: %d\n", ret);
> ret = -ENXIO;
> - goto err_pm;
> + goto err_regulator;
> }
>
> ret = i2c_hid_fetch_hid_descriptor(ihid);
> if (ret < 0)
> - goto err_pm;
> + goto err_regulator;
>
> ret = i2c_hid_init_irq(client);
> if (ret < 0)
> - goto err_pm;
> + goto err_regulator;
>
> hid = hid_allocate_device();
> if (IS_ERR(hid)) {
> @@ -1154,9 +1100,6 @@ static int i2c_hid_probe(struct i2c_client *client,
> goto err_mem_free;
> }
>
> - if (!(ihid->quirks & I2C_HID_QUIRK_NO_RUNTIME_PM))
> - pm_runtime_put(&client->dev);
> -
> return 0;
>
> err_mem_free:
> @@ -1165,10 +1108,6 @@ static int i2c_hid_probe(struct i2c_client *client,
> err_irq:
> free_irq(client->irq, ihid);
>
> -err_pm:
> - pm_runtime_put_noidle(&client->dev);
> - pm_runtime_disable(&client->dev);
> -
> err_regulator:
> regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
> ihid->pdata.supplies);
> @@ -1181,12 +1120,6 @@ static int i2c_hid_remove(struct i2c_client *client)
> struct i2c_hid *ihid = i2c_get_clientdata(client);
> struct hid_device *hid;
>
> - if (!(ihid->quirks & I2C_HID_QUIRK_NO_RUNTIME_PM))
> - pm_runtime_get_sync(&client->dev);
> - pm_runtime_disable(&client->dev);
> - pm_runtime_set_suspended(&client->dev);
> - pm_runtime_put_noidle(&client->dev);
> -
> hid = ihid->hid;
> hid_destroy_device(hid);
>
> @@ -1219,25 +1152,15 @@ static int i2c_hid_suspend(struct device *dev)
> int wake_status;
>
> if (hid->driver && hid->driver->suspend) {
> - /*
> - * Wake up the device so that IO issues in
> - * HID driver's suspend code can succeed.
> - */
> - ret = pm_runtime_resume(dev);
> - if (ret < 0)
> - return ret;
> -
> ret = hid->driver->suspend(hid, PMSG_SUSPEND);
> if (ret < 0)
> return ret;
> }
>
> - if (!pm_runtime_suspended(dev)) {
> - /* Save some power */
> - i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
> + /* Save some power */
> + i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
>
> - disable_irq(client->irq);
> - }
> + disable_irq(client->irq);
>
> if (device_may_wakeup(&client->dev)) {
> wake_status = enable_irq_wake(client->irq);
> @@ -1279,11 +1202,6 @@ static int i2c_hid_resume(struct device *dev)
> wake_status);
> }
>
> - /* We'll resume to full power */
> - pm_runtime_disable(dev);
> - pm_runtime_set_active(dev);
> - pm_runtime_enable(dev);
> -
> enable_irq(client->irq);
>
> /* Instead of resetting device, simply powers the device on. This
> @@ -1304,30 +1222,8 @@ static int i2c_hid_resume(struct device *dev)
> }
> #endif
>
> -#ifdef CONFIG_PM
> -static int i2c_hid_runtime_suspend(struct device *dev)
> -{
> - struct i2c_client *client = to_i2c_client(dev);
> -
> - i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
> - disable_irq(client->irq);
> - return 0;
> -}
> -
> -static int i2c_hid_runtime_resume(struct device *dev)
> -{
> - struct i2c_client *client = to_i2c_client(dev);
> -
> - enable_irq(client->irq);
> - i2c_hid_set_power(client, I2C_HID_PWR_ON);
> - return 0;
> -}
> -#endif
> -
> static const struct dev_pm_ops i2c_hid_pm = {
> SET_SYSTEM_SLEEP_PM_OPS(i2c_hid_suspend, i2c_hid_resume)
> - SET_RUNTIME_PM_OPS(i2c_hid_runtime_suspend, i2c_hid_runtime_resume,
> - NULL)
> };
>
> static const struct i2c_device_id i2c_hid_id_table[] = {
> --
> 2.17.1
>
