From a9eb186e13144782232cc6fa731441be54baf505 Mon Sep 17 00:00:00 2001 From: Joseph Lo Date: Fri, 16 Dec 2016 18:57:36 +0100 Subject: [PATCH] mfd: cros_ec: Prevent data transfer while device is suspended The cros_ec driver is still active while the device is suspended. Besides that, it also tries to transfer data even after the I2C host had been suspended. This patch uses a simple flag to prevent this. Signed-off-by: Joseph Lo Signed-off-by: Thierry Escande Signed-off-by: Lee Jones --- drivers/mfd/cros_ec.c | 2 ++ drivers/platform/chrome/cros_ec_proto.c | 5 +++++ include/linux/mfd/cros_ec.h | 2 ++ 3 files changed, 9 insertions(+) diff --git a/drivers/mfd/cros_ec.c b/drivers/mfd/cros_ec.c index abd83424b498..ad48633c9a47 100644 --- a/drivers/mfd/cros_ec.c +++ b/drivers/mfd/cros_ec.c @@ -165,6 +165,7 @@ int cros_ec_suspend(struct cros_ec_device *ec_dev) disable_irq(ec_dev->irq); ec_dev->was_wake_device = ec_dev->wake_enabled; + ec_dev->suspended = true; return 0; } @@ -179,6 +180,7 @@ static void cros_ec_drain_events(struct cros_ec_device *ec_dev) int cros_ec_resume(struct cros_ec_device *ec_dev) { + ec_dev->suspended = false; enable_irq(ec_dev->irq); /* diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c index 04053fe1e980..ed5dee744c74 100644 --- a/drivers/platform/chrome/cros_ec_proto.c +++ b/drivers/platform/chrome/cros_ec_proto.c @@ -447,6 +447,11 @@ static int get_next_event(struct cros_ec_device *ec_dev) struct cros_ec_command *msg = (struct cros_ec_command *)&buffer; int ret; + if (ec_dev->suspended) { + dev_dbg(ec_dev->dev, "Device suspended.\n"); + return -EHOSTDOWN; + } + msg->version = 0; msg->command = EC_CMD_GET_NEXT_EVENT; msg->insize = sizeof(ec_dev->event_data); diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h index f62043a75f43..7a01c94496f1 100644 --- a/include/linux/mfd/cros_ec.h +++ b/include/linux/mfd/cros_ec.h @@ -103,6 +103,7 @@ struct cros_ec_command { * @din_size: size of din buffer to allocate (zero to use static din) * @dout_size: size of dout buffer to allocate (zero to use static dout) * @wake_enabled: true if this device can wake the system from sleep + * @suspended: true if this device had been suspended * @cmd_xfer: send command to EC and get response * Returns the number of bytes received if the communication succeeded, but * that doesn't mean the EC was happy with the command. The caller @@ -136,6 +137,7 @@ struct cros_ec_device { int din_size; int dout_size; bool wake_enabled; + bool suspended; int (*cmd_xfer)(struct cros_ec_device *ec, struct cros_ec_command *msg); int (*pkt_xfer)(struct cros_ec_device *ec, -- 2.20.1