aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorRafael J. Wysocki <rafael.j.wysocki@intel.com>2014-07-10 21:03:57 +0200
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2014-07-10 21:03:57 +0200
commit0b80a8ff07e0ff006dcb5286afaeddcb1114d0f1 (patch)
tree05f3ee4b19510b8c9f37caeebb529ad15dc8222e
parent4488c99b6397ab7db14c9ffeb8e94f3fca5dbb19 (diff)
parented4b197ddd4d7aa6623e7777ea326c67c3a6b8ed (diff)
downloadlinux-0b80a8ff07e0ff006dcb5286afaeddcb1114d0f1.tar.gz
Merge branch 'acpi-ec'
* acpi-ec: ACPI / EC: Free saved_ec on error exit path ACPI / EC: Add detailed fields debugging support of EC_SC(R). ACPI / EC: Update revision due to recent changes ACPI / EC: Fix race condition in ec_transaction_completed() ACPI / EC: Remove duplicated ec_wait_ibf0() waiter ACPI / EC: Add asynchronous command byte write support ACPI / EC: Avoid race condition related to advance_transaction()
-rw-r--r--drivers/acpi/ec.c164
1 files changed, 85 insertions, 79 deletions
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index ad11ba4a412..a66ab658abb 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -1,11 +1,14 @@
/*
- * ec.c - ACPI Embedded Controller Driver (v2.1)
+ * ec.c - ACPI Embedded Controller Driver (v2.2)
*
- * Copyright (C) 2006-2008 Alexey Starikovskiy <astarikovskiy@suse.de>
- * Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
- * Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
- * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
- * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ * Copyright (C) 2001-2014 Intel Corporation
+ * Author: 2014 Lv Zheng <lv.zheng@intel.com>
+ * 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
+ * 2006 Denis Sadykov <denis.m.sadykov@intel.com>
+ * 2004 Luming Yu <luming.yu@intel.com>
+ * 2001, 2002 Andy Grover <andrew.grover@intel.com>
+ * 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ * Copyright (C) 2008 Alexey Starikovskiy <astarikovskiy@suse.de>
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
@@ -52,6 +55,7 @@
/* EC status register */
#define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */
#define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */
+#define ACPI_EC_FLAG_CMD 0x08 /* Input buffer contains a command */
#define ACPI_EC_FLAG_BURST 0x10 /* burst mode */
#define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */
@@ -78,6 +82,9 @@ enum {
EC_FLAGS_BLOCKED, /* Transactions are blocked */
};
+#define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */
+#define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */
+
/* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
module_param(ec_delay, uint, 0644);
@@ -109,7 +116,7 @@ struct transaction {
u8 ri;
u8 wlen;
u8 rlen;
- bool done;
+ u8 flags;
};
struct acpi_ec *boot_ec, *first_ec;
@@ -127,83 +134,104 @@ static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */
static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
{
u8 x = inb(ec->command_addr);
- pr_debug("---> status = 0x%2.2x\n", x);
+ pr_debug("EC_SC(R) = 0x%2.2x "
+ "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d\n",
+ x,
+ !!(x & ACPI_EC_FLAG_SCI),
+ !!(x & ACPI_EC_FLAG_BURST),
+ !!(x & ACPI_EC_FLAG_CMD),
+ !!(x & ACPI_EC_FLAG_IBF),
+ !!(x & ACPI_EC_FLAG_OBF));
return x;
}
static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
{
u8 x = inb(ec->data_addr);
- pr_debug("---> data = 0x%2.2x\n", x);
+ pr_debug("EC_DATA(R) = 0x%2.2x\n", x);
return x;
}
static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
{
- pr_debug("<--- command = 0x%2.2x\n", command);
+ pr_debug("EC_SC(W) = 0x%2.2x\n", command);
outb(command, ec->command_addr);
}
static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
{
- pr_debug("<--- data = 0x%2.2x\n", data);
+ pr_debug("EC_DATA(W) = 0x%2.2x\n", data);
outb(data, ec->data_addr);
}
-static int ec_transaction_done(struct acpi_ec *ec)
+static int ec_transaction_completed(struct acpi_ec *ec)
{
unsigned long flags;
int ret = 0;
spin_lock_irqsave(&ec->lock, flags);
- if (!ec->curr || ec->curr->done)
+ if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE))
ret = 1;
spin_unlock_irqrestore(&ec->lock, flags);
return ret;
}
-static void start_transaction(struct acpi_ec *ec)
+static bool advance_transaction(struct acpi_ec *ec)
{
- ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
- ec->curr->done = false;
- acpi_ec_write_cmd(ec, ec->curr->command);
-}
-
-static void advance_transaction(struct acpi_ec *ec, u8 status)
-{
- unsigned long flags;
struct transaction *t;
+ u8 status;
+ bool wakeup = false;
- spin_lock_irqsave(&ec->lock, flags);
+ pr_debug("===== %s =====\n", in_interrupt() ? "IRQ" : "TASK");
+ status = acpi_ec_read_status(ec);
t = ec->curr;
if (!t)
- goto unlock;
- if (t->wlen > t->wi) {
- if ((status & ACPI_EC_FLAG_IBF) == 0)
- acpi_ec_write_data(ec,
- t->wdata[t->wi++]);
- else
- goto err;
- } else if (t->rlen > t->ri) {
- if ((status & ACPI_EC_FLAG_OBF) == 1) {
- t->rdata[t->ri++] = acpi_ec_read_data(ec);
- if (t->rlen == t->ri)
- t->done = true;
+ goto err;
+ if (t->flags & ACPI_EC_COMMAND_POLL) {
+ if (t->wlen > t->wi) {
+ if ((status & ACPI_EC_FLAG_IBF) == 0)
+ acpi_ec_write_data(ec, t->wdata[t->wi++]);
+ else
+ goto err;
+ } else if (t->rlen > t->ri) {
+ if ((status & ACPI_EC_FLAG_OBF) == 1) {
+ t->rdata[t->ri++] = acpi_ec_read_data(ec);
+ if (t->rlen == t->ri) {
+ t->flags |= ACPI_EC_COMMAND_COMPLETE;
+ wakeup = true;
+ }
+ } else
+ goto err;
+ } else if (t->wlen == t->wi &&
+ (status & ACPI_EC_FLAG_IBF) == 0) {
+ t->flags |= ACPI_EC_COMMAND_COMPLETE;
+ wakeup = true;
+ }
+ return wakeup;
+ } else {
+ if ((status & ACPI_EC_FLAG_IBF) == 0) {
+ acpi_ec_write_cmd(ec, t->command);
+ t->flags |= ACPI_EC_COMMAND_POLL;
} else
goto err;
- } else if (t->wlen == t->wi &&
- (status & ACPI_EC_FLAG_IBF) == 0)
- t->done = true;
- goto unlock;
+ return wakeup;
+ }
err:
/*
* If SCI bit is set, then don't think it's a false IRQ
* otherwise will take a not handled IRQ as a false one.
*/
- if (in_interrupt() && !(status & ACPI_EC_FLAG_SCI))
- ++t->irq_count;
+ if (!(status & ACPI_EC_FLAG_SCI)) {
+ if (in_interrupt() && t)
+ ++t->irq_count;
+ }
+ return wakeup;
+}
-unlock:
- spin_unlock_irqrestore(&ec->lock, flags);
+static void start_transaction(struct acpi_ec *ec)
+{
+ ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
+ ec->curr->flags = 0;
+ (void)advance_transaction(ec);
}
static int acpi_ec_sync_query(struct acpi_ec *ec, u8 *data);
@@ -228,15 +256,17 @@ static int ec_poll(struct acpi_ec *ec)
/* don't sleep with disabled interrupts */
if (EC_FLAGS_MSI || irqs_disabled()) {
udelay(ACPI_EC_MSI_UDELAY);
- if (ec_transaction_done(ec))
+ if (ec_transaction_completed(ec))
return 0;
} else {
if (wait_event_timeout(ec->wait,
- ec_transaction_done(ec),
+ ec_transaction_completed(ec),
msecs_to_jiffies(1)))
return 0;
}
- advance_transaction(ec, acpi_ec_read_status(ec));
+ spin_lock_irqsave(&ec->lock, flags);
+ (void)advance_transaction(ec);
+ spin_unlock_irqrestore(&ec->lock, flags);
} while (time_before(jiffies, delay));
pr_debug("controller reset, restart transaction\n");
spin_lock_irqsave(&ec->lock, flags);
@@ -268,23 +298,6 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
return ret;
}
-static int ec_check_ibf0(struct acpi_ec *ec)
-{
- u8 status = acpi_ec_read_status(ec);
- return (status & ACPI_EC_FLAG_IBF) == 0;
-}
-
-static int ec_wait_ibf0(struct acpi_ec *ec)
-{
- unsigned long delay = jiffies + msecs_to_jiffies(ec_delay);
- /* interrupt wait manually if GPE mode is not active */
- while (time_before(jiffies, delay))
- if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
- msecs_to_jiffies(1)))
- return 0;
- return -ETIME;
-}
-
static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
{
int status;
@@ -305,12 +318,6 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
goto unlock;
}
}
- if (ec_wait_ibf0(ec)) {
- pr_err("input buffer is not empty, "
- "aborting transaction\n");
- status = -ETIME;
- goto end;
- }
pr_debug("transaction start (cmd=0x%02x, addr=0x%02x)\n",
t->command, t->wdata ? t->wdata[0] : 0);
/* disable GPE during transaction if storm is detected */
@@ -334,7 +341,6 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
}
pr_debug("transaction end\n");
-end:
if (ec->global_lock)
acpi_release_global_lock(glk);
unlock:
@@ -634,17 +640,14 @@ static int ec_check_sci(struct acpi_ec *ec, u8 state)
static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
u32 gpe_number, void *data)
{
+ unsigned long flags;
struct acpi_ec *ec = data;
- u8 status = acpi_ec_read_status(ec);
- pr_debug("~~~> interrupt, status:0x%02x\n", status);
-
- advance_transaction(ec, status);
- if (ec_transaction_done(ec) &&
- (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
+ spin_lock_irqsave(&ec->lock, flags);
+ if (advance_transaction(ec))
wake_up(&ec->wait);
- ec_check_sci(ec, acpi_ec_read_status(ec));
- }
+ spin_unlock_irqrestore(&ec->lock, flags);
+ ec_check_sci(ec, acpi_ec_read_status(ec));
return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE;
}
@@ -1066,8 +1069,10 @@ int __init acpi_ec_ecdt_probe(void)
/* fall through */
}
- if (EC_FLAGS_SKIP_DSDT_SCAN)
+ if (EC_FLAGS_SKIP_DSDT_SCAN) {
+ kfree(saved_ec);
return -ENODEV;
+ }
/* This workaround is needed only on some broken machines,
* which require early EC, but fail to provide ECDT */
@@ -1105,6 +1110,7 @@ install:
}
error:
kfree(boot_ec);
+ kfree(saved_ec);
boot_ec = NULL;
return -ENODEV;
}