1 files changed, 85 insertions, 79 deletions

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index ad11ba4a412d..a66ab658abbc 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;
 }