Hi Robin,
On Wed, Sep 04, 2019 at 06:23:29AM +0000, Robin van der Gracht wrote:
> The first generation i.MX6 processors does not send an interrupt when the
> power key is pressed. It sends a power down request interrupt if the key is
> released before a hard shutdown (5 second press). This should allow
> software to bring down the SoC safely.
>
> For this driver to work as a regular power key with the older SoCs, we need
> to send a keypress AND release when we get the power down request irq.
>
> Signed-off-by: Robin van der Gracht <robin@xxxxxxxxxxx>
> ---
>
> Changes v2 -> v3:
> - Drop alt compatible string for identifying first revision snvs hardware,
> read minor revision from register instead.
> - Drop imx6qdl.dtsi modification and device-tree binding documentation.
> - Add an additional input_sync() to create 2 seperate input reports for press
> and release.
>
> drivers/input/keyboard/Kconfig | 2 +-
> drivers/input/keyboard/snvs_pwrkey.c | 28 ++++++++++++++++++++++++++--
> 2 files changed, 27 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
> index 7c4f19dab34f..937e58da5ce1 100644
> --- a/drivers/input/keyboard/Kconfig
> +++ b/drivers/input/keyboard/Kconfig
> @@ -436,7 +436,7 @@ config KEYBOARD_SNVS_PWRKEY
> depends on OF
> help
> This is the snvs powerkey driver for the Freescale i.MX application
> - processors that are newer than i.MX6 SX.
> + processors.
>
> To compile this driver as a module, choose M here; the
> module will be called snvs_pwrkey.
> diff --git a/drivers/input/keyboard/snvs_pwrkey.c b/drivers/input/keyboard/snvs_pwrkey.c
> index 5342d8d45f81..828580eee0d2 100644
> --- a/drivers/input/keyboard/snvs_pwrkey.c
> +++ b/drivers/input/keyboard/snvs_pwrkey.c
> @@ -19,6 +19,7 @@
> #include <linux/mfd/syscon.h>
> #include <linux/regmap.h>
>
> +#define SNVS_HPVIDR1_REG 0xF8
> #define SNVS_LPSR_REG 0x4C /* LP Status Register */
> #define SNVS_LPCR_REG 0x38 /* LP Control Register */
> #define SNVS_HPSR_REG 0x14
> @@ -37,6 +38,7 @@ struct pwrkey_drv_data {
> int wakeup;
> struct timer_list check_timer;
> struct input_dev *input;
> + u8 minor_rev;
> };
>
> static void imx_imx_snvs_check_for_events(struct timer_list *t)
> @@ -45,6 +47,20 @@ static void imx_imx_snvs_check_for_events(struct timer_list *t)
> struct input_dev *input = pdata->input;
> u32 state;
>
> + if (pdata->minor_rev == 0) {
> + /*
> + * The first generation i.MX6 SoCs only sends an interrupt on
> + * button release. To mimic power-key usage, we'll prepend a
> + * press event.
> + */
> + input_report_key(input, pdata->keycode, 1);
> + input_sync(input);
> + input_report_key(input, pdata->keycode, 0);
> + input_sync(input);
> + pm_relax(input->dev.parent);
> + return;
> + }
> +
> regmap_read(pdata->snvs, SNVS_HPSR_REG, &state);
> state = state & SNVS_HPSR_BTN ? 1 : 0;
>
> @@ -67,13 +83,17 @@ static irqreturn_t imx_snvs_pwrkey_interrupt(int irq, void *dev_id)
> {
> struct platform_device *pdev = dev_id;
> struct pwrkey_drv_data *pdata = platform_get_drvdata(pdev);
> + unsigned long expire = jiffies;
> u32 lp_status;
>
> pm_wakeup_event(pdata->input->dev.parent, 0);
>
> regmap_read(pdata->snvs, SNVS_LPSR_REG, &lp_status);
> - if (lp_status & SNVS_LPSR_SPO)
> - mod_timer(&pdata->check_timer, jiffies + msecs_to_jiffies(DEBOUNCE_TIME));
> + if (lp_status & SNVS_LPSR_SPO) {
> + if (pdata->minor_rev > 0)
> + expire = jiffies + msecs_to_jiffies(DEBOUNCE_TIME);
> + mod_timer(&pdata->check_timer, expire);
Why do we even need to fire the timer in case of the first generation
hardware? Just send press and release events directly from the ISR.
Thanks.
--
Dmitry
