Re: [PATCH v3] input: keyboard: snvs_pwrkey: Send key events for i.MX6 S, DL and Q

From: robin
Date: Fri Sep 13 2019 - 03:39:29 EST


On 2019-09-04 08:52, Marco Felsch wrote:
Hi Robin,

thanks for the patch it looks quite good, just two minor nitpicks.

On 19-09-04 06:23, 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) {

Should we use a define here and ..

+ /*
+ * 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)

here? Just a nitpick, feel free to add/drop it.

Like a Macro?

#define FIRST_HW_REV(pdata) (pdata->minor_rev == 0)

if (FIRST_HW_REV(pdata) {
...
}


or just a define to identify the minor rev used for the first hw revision


#define FIRST_HW_MINOR_REV 0

if (pdata->minor_rev == FIRST_HW_MINOR_REV) {
...
}

Regards,
Robin van der Gracht