niansa-misc/linux
1
0
Fork 0
mirror of synced 2025-03-06 20:59:54 +01:00
Code Issues Projects Releases Packages Wiki Activity

platform/chrome: cros_ec: Query EC protocol version if EC transitions between RO/RW

Browse source 
RO and RW of EC may have different EC protocol version. If EC transitions
between RO and RW, but AP does not reboot (this is true for fingerprint
microcontroller / cros_fp, but not true for main ec / cros_ec), the AP
still uses the protocol version queried before transition, which can
cause problems. In the case of fingerprint microcontroller, this causes
AP to send the wrong version of EC_CMD_GET_NEXT_EVENT to RO in the
interrupt handler, which in turn prevents RO to clear the interrupt
line to AP, in an infinite loop.

Once an EC_HOST_EVENT_INTERFACE_READY is received, we know that there
might have been a transition between RO and RW, so re-query the protocol.

Signed-off-by: Yicheng Li <yichengli@chromium.org>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
This commit is contained in:
Yicheng Li 2020-02-03 14:53:56 -08:00 • committed by Enric Balletbo i Serra
parent 8673e944b5
commit 42cd0ab476
2 changed files with 34 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

30
drivers/platform/chrome/cros_ec.c
View file

@ -138,6 +138,24 @@ static int cros_ec_sleep_event(struct cros_ec_device *ec_dev, u8 sleep_event)
return ret; return ret;
} }
static int cros_ec_ready_event(struct notifier_block *nb,
unsigned long queued_during_suspend,
void *_notify)
{
struct cros_ec_device *ec_dev = container_of(nb, struct cros_ec_device,
notifier_ready);
u32 host_event = cros_ec_get_host_event(ec_dev);
if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_INTERFACE_READY)) {
mutex_lock(&ec_dev->lock);
cros_ec_query_all(ec_dev);
mutex_unlock(&ec_dev->lock);
return NOTIFY_OK;
}
return NOTIFY_DONE;
}
/** /**
* cros_ec_register() - Register a new ChromeOS EC, using the provided info. * cros_ec_register() - Register a new ChromeOS EC, using the provided info.
* @ec_dev: Device to register. * @ec_dev: Device to register.
@ -237,6 +255,18 @@ int cros_ec_register(struct cros_ec_device *ec_dev)
dev_dbg(ec_dev->dev, "Error %d clearing sleep event to ec", dev_dbg(ec_dev->dev, "Error %d clearing sleep event to ec",
err); err);
if (ec_dev->mkbp_event_supported) {
/*
* Register the notifier for EC_HOST_EVENT_INTERFACE_READY
* event.
*/
ec_dev->notifier_ready.notifier_call = cros_ec_ready_event;
err = blocking_notifier_chain_register(&ec_dev->event_notifier,
&ec_dev->notifier_ready);
if (err)
return err;
}
dev_info(dev, "Chrome EC device registered\n"); dev_info(dev, "Chrome EC device registered\n");
return 0; return 0;

4
include/linux/platform_data/cros_ec_proto.h
View file

@ -125,6 +125,9 @@ struct cros_ec_command {
* @host_event_wake_mask: Mask of host events that cause wake from suspend. * @host_event_wake_mask: Mask of host events that cause wake from suspend.
* @last_event_time: exact time from the hard irq when we got notified of * @last_event_time: exact time from the hard irq when we got notified of
* a new event. * a new event.
* @notifier_ready: The notifier_block to let the kernel re-query EC
* communication protocol when the EC sends
* EC_HOST_EVENT_INTERFACE_READY.
* @ec: The platform_device used by the mfd driver to interface with the * @ec: The platform_device used by the mfd driver to interface with the
* main EC. * main EC.
* @pd: The platform_device used by the mfd driver to interface with the * @pd: The platform_device used by the mfd driver to interface with the
@ -166,6 +169,7 @@ struct cros_ec_device {
u32 host_event_wake_mask; u32 host_event_wake_mask;
u32 last_resume_result; u32 last_resume_result;
ktime_t last_event_time; ktime_t last_event_time;
struct notifier_block notifier_ready;
/* The platform devices used by the mfd driver */ /* The platform devices used by the mfd driver */
struct platform_device *ec; struct platform_device *ec;