Re: [PATCH v3 3/3] drm/privacy_screen_x86: Add entry for ChromeOS privacy-screen

Hi,

On 12/20/21 23:28, Rajat Jain wrote:

Add a static entry in the x86 table, to detect and wait for privacy-screen on some ChromeOS platforms.

Please note that this means that if CONFIG_CHROMEOS_PRIVACY_SCREEN is enabled, and if "GOOG0010" device is found in ACPI, then the i915 probe shall return EPROBE_DEFER until a platform driver actually registers the privacy-screen: https://hansdegoede.livejournal.com/25948.html

Signed-off-by: Rajat Jain rajatja@google.com

v3: * Remove the pr_info() from detect_chromeos_privacy_screen(), instead enhance the one already present in drm_privacy_screen_lookup_init() v2: * Use #if instead of #elif * Reorder the patches in the series. * Rebased on drm-tip

drivers/gpu/drm/drm_privacy_screen_x86.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_privacy_screen_x86.c b/drivers/gpu/drm/drm_privacy_screen_x86.c index a2cafb294ca6..0fdd2b500e6d 100644 --- a/drivers/gpu/drm/drm_privacy_screen_x86.c +++ b/drivers/gpu/drm/drm_privacy_screen_x86.c @@ -47,6 +47,16 @@ static bool __init detect_thinkpad_privacy_screen(void) } #endif

+#if IS_ENABLED(CONFIG_CHROMEOS_PRIVACY_SCREEN) +static bool __init detect_chromeos_privacy_screen(void) +{

• if (!acpi_dev_present("GOOG0010", NULL, -1))

• return false;
  

• return true;

This can be simplified to just:

return acpi_dev_present("GOOG0010", NULL, -1);

+} +#endif

static const struct arch_init_data arch_init_data[] __initconst = { #if IS_ENABLED(CONFIG_THINKPAD_ACPI) { @@ -58,6 +68,16 @@ static const struct arch_init_data arch_init_data[] __initconst = { .detect = detect_thinkpad_privacy_screen, }, #endif +#if IS_ENABLED(CONFIG_CHROMEOS_PRIVACY_SCREEN)

• {

• .lookup = {
  

• 	.dev_id = NULL,
  

• 	.con_id = NULL,
  

• 	.provider = "privacy_screen-GOOG0010:00",
  

• },
  

• .detect = detect_chromeos_privacy_screen,
  

• },

+#endif };

void __init drm_privacy_screen_lookup_init(void) @@ -68,7 +88,8 @@ void __init drm_privacy_screen_lookup_init(void) if (!arch_init_data[i].detect()) continue;

• pr_info("Found '%s' privacy-screen provider\n",
  

• pr_info("Found '%s' privacy-screen provider."
  

• 	"Might have to defer probe for it...\n",
  arch_init_data[i].lookup.provider);
  

I'm afraid this change in the log message will only confuse users, and for your goal of checking if a privacy-screen provider has been detected, the original message is good enough.

Please drop this part of the patch.

Regards,

Hans

/* Make a copy because arch_init_data is __initconst */