Re: [PATCH v2] Input: atkbd - Skip ATKBD_CMD_GETID in translated mode

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

Hi Hans,

On Wed, Nov 15, 2023 at 06:46:25PM +0100, Hans de Goede wrote:
> There have been multiple reports of keyboard issues on recent laptop models
> which can be worked around by setting i8042.dumbkbd, with the downside
> being this breaks the capslock LED.
> 
> It seems that these issues are caused by recent laptops getting confused by
> ATKBD_CMD_GETID. Rather then adding and endless growing list of quirks for
> this, just skip ATKBD_CMD_GETID alltogether on laptops in translated mode.
> 
> The main goal of sending ATKBD_CMD_GETID is to skip binding to ps/2
> mice/touchpads and those are never used in translated mode.
> 
> Examples of laptop models which benefit from skipping ATKBD_CMD_GETID:
> 
> * "HP Laptop 15s-fq2xxx", "HP laptop 15s-fq4xxx" and "HP Laptop 15-dy2xxx"
>   models the kbd stops working for the first 2 - 5 minutes after boot
>   (waiting for EC watchdog reset?)
> 
> * On "HP Spectre x360 13-aw2xxx" atkbd fails to probe the keyboard
> 
> * At least 9 different Lenovo models have issues with ATKBD_CMD_GETID, see:
>   https://github.com/yescallop/atkbd-nogetid
> 
> This has been tested on:
> 
> 1. A MSI B550M PRO-VDH WIFI desktop, where the i8042 controller is not
>    in translated mode when no keyboard is plugged in and with a ps/2 kbd
>    a "AT Translated Set 2 keyboard" /dev/input/event# node shows up
> 
> 2. A Lenovo ThinkPad X1 Yoga gen 8 (always has a translated set 2 keyboard)
> 
> Reported-by: Shang Ye <yesh25@mail2.sysu.edu.cn>
> Closes: https://lore.kernel.org/linux-input/886D6167733841AE+20231017135318.11142-1-yesh25@mail2.sysu.edu.cn/
> Closes: https://github.com/yescallop/atkbd-nogetid
> Reported-by: gurevitch <mail@gurevit.ch>
> Closes: https://lore.kernel.org/linux-input/2iAJTwqZV6lQs26cTb38RNYqxvsink6SRmrZ5h0cBUSuf9NT0tZTsf9fEAbbto2maavHJEOP8GA1evlKa6xjKOsaskDhtJWxjcnrgPigzVo=@gurevit.ch/
> Reported-by: Egor Ignatov <egori@altlinux.org>
> Closes: https://lore.kernel.org/all/20210609073333.8425-1-egori@altlinux.org/
> Reported-by: Anton Zhilyaev <anton@cpp.in>
> Closes: https://lore.kernel.org/linux-input/20210201160336.16008-1-anton@cpp.in/
> Closes: https://bugzilla.redhat.com/show_bug.cgi?id=2086156
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
> Note this supersedes my previous atkbd series:
> https://lore.kernel.org/linux-input/20231005201544.26983-1-hdegoede@redhat.com/
> ---
> Changes in v2:
> - Add DMI check for laptop chassis types and only skip ATKBD_CMD_GETID
>   on laptops with the i8042 in translated mode
> ---
>  drivers/input/keyboard/atkbd.c | 61 +++++++++++++++++++++++++++++++---
>  1 file changed, 57 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/input/keyboard/atkbd.c b/drivers/input/keyboard/atkbd.c
> index c92e544c792d..5667f1e80839 100644
> --- a/drivers/input/keyboard/atkbd.c
> +++ b/drivers/input/keyboard/atkbd.c
> @@ -765,6 +765,59 @@ static void atkbd_deactivate(struct atkbd *atkbd)
>  			ps2dev->serio->phys);
>  }
>  
> +#ifdef CONFIG_X86
> +static const struct dmi_system_id atkbd_dmi_laptop_table[] = {
> +	{
> +		.matches = {
> +			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "8"), /* Portable */
> +		},
> +	},
> +	{
> +		.matches = {
> +			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "9"), /* Laptop */
> +		},
> +	},
> +	{
> +		.matches = {
> +			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "10"), /* Notebook */
> +		},
> +	},
> +	{
> +		.matches = {
> +			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "14"), /* Sub-Notebook */
> +		},
> +	},
> +	{
> +		.matches = {
> +			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "31"), /* Convertible */
> +		},
> +	},
> +	{
> +		.matches = {
> +			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "32"), /* Detachable */
> +		},
> +	},
> +	{ }
> +};

Thank you for making the changes, however I wonder if we should
open-code check for the chassis type, as DMI can be quite bloated and
here we are dealing with exactly one field. Something like this:

diff --git a/drivers/input/keyboard/atkbd.c b/drivers/input/keyboard/atkbd.c
index 5667f1e80839..786f00f6b7fd 100644
--- a/drivers/input/keyboard/atkbd.c
+++ b/drivers/input/keyboard/atkbd.c
@@ -766,39 +766,24 @@ static void atkbd_deactivate(struct atkbd *atkbd)
 }
 
 #ifdef CONFIG_X86
-static const struct dmi_system_id atkbd_dmi_laptop_table[] = {
-	{
-		.matches = {
-			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "8"), /* Portable */
-		},
-	},
-	{
-		.matches = {
-			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "9"), /* Laptop */
-		},
-	},
-	{
-		.matches = {
-			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "10"), /* Notebook */
-		},
-	},
-	{
-		.matches = {
-			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "14"), /* Sub-Notebook */
-		},
-	},
-	{
-		.matches = {
-			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "31"), /* Convertible */
-		},
-	},
-	{
-		.matches = {
-			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "32"), /* Detachable */
-		},
-	},
-	{ }
-};
+static bool atkbd_is_portable_device(void)
+{
+	static const char * const chassis_types[] = {
+		"8",	/* Portable */
+		"9",	/* Laptop */
+		"10",	/* Notebook */
+		"14",	/* Sub-Notebook */
+		"31",	/* Convertible */
+		"32",	/* Detachable */
+	};
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(chassis_types); i++)
+		if (dmi_match(DMI_CHASSIS_TYPE, chassis_types[i]))
+			return true;
+
+	return false;
+}
 
 /*
  * On many modern laptops ATKBD_CMD_GETID may cause problems, on these laptops
@@ -812,7 +797,7 @@ static const struct dmi_system_id atkbd_dmi_laptop_table[] = {
  */
 static bool atkbd_skip_getid(struct atkbd *atkbd)
 {
-	return atkbd->translated && dmi_check_system(atkbd_dmi_laptop_table);
+	return atkbd->translated && atkbd_is_portable_device();
 }
 #else
 static inline bool atkbd_skip_getid(struct atkbd *atkbd) { return false; }


It gives me slightly smaller output:

dtor@dtor-ws:~/kernel/work (master *)$ size drivers/input/keyboard/atkbd.o.old
   text    data     bss     dec     hex filename
  28407    1512      37   29956    7504 drivers/input/keyboard/atkbd.o.old
dtor@dtor-ws:~/kernel/work (master *)$ size drivers/input/keyboard/atkbd.o
   text    data     bss     dec     hex filename
  26107    1512      37   27656    6c08 drivers/input/keyboard/atkbd.o

Please let me know if this works for you and I can combine on my end.

Thanks.

-- 
Dmitry