Input: libps2 - additional locking for i8042 ports

The serio ports on i8042 are not completely isolated; while we provide
enough locking to ensure proper serialization when accessing control
and data registers AUX and KBD ports can still have an effect on each
other on PS/2 protocol level. The most prominent effect is that
issuing a command for the device connected to one port may cause
abort of the command currently executing by the device connected to
another port.

Since i8042 nor serio subsystem are not aware of the details of the
PS/2 protocol (length of the commands and their replies and so on) the
locking should be done on libps2 level by adding special handling when
we see that we are dealing with serio port on i8042.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1 files changed, 10 insertions, 8 deletions

diff --git a/drivers/input/mouse/sentelic.c b/drivers/input/mouse/sentelic.c
index 84e2fc04d11b..f84cbd97c884 100644
--- a/drivers/input/mouse/sentelic.c
+++ b/drivers/input/mouse/sentelic.c
@@ -92,7 +92,8 @@ static int fsp_reg_read(struct psmouse *psmouse, int reg_addr, int *reg_val)
          */
         ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE);
         psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
-        mutex_lock(&ps2dev->cmd_mutex);
+
+        ps2_begin_command(ps2dev);
 
         if (ps2_sendbyte(ps2dev, 0xf3, FSP_CMD_TIMEOUT) < 0)
                 goto out;
@@ -126,7 +127,7 @@ static int fsp_reg_read(struct psmouse *psmouse, int reg_addr, int *reg_val)
         rc = 0;
 
  out:
-        mutex_unlock(&ps2dev->cmd_mutex);
+        ps2_end_command(ps2dev);
         ps2_command(ps2dev, NULL, PSMOUSE_CMD_ENABLE);
         psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
         dev_dbg(&ps2dev->serio->dev, "READ REG: 0x%02x is 0x%02x (rc = %d)\n",
@@ -140,7 +141,7 @@ static int fsp_reg_write(struct psmouse *psmouse, int reg_addr, int reg_val)
         unsigned char v;
         int rc = -1;
 
-        mutex_lock(&ps2dev->cmd_mutex);
+        ps2_begin_command(ps2dev);
 
         if (ps2_sendbyte(ps2dev, 0xf3, FSP_CMD_TIMEOUT) < 0)
                 goto out;
@@ -179,7 +180,7 @@ static int fsp_reg_write(struct psmouse *psmouse, int reg_addr, int reg_val)
         rc = 0;
 
  out:
-        mutex_unlock(&ps2dev->cmd_mutex);
+        ps2_end_command(ps2dev);
         dev_dbg(&ps2dev->serio->dev, "WRITE REG: 0x%02x to 0x%02x (rc = %d)\n",
                 reg_addr, reg_val, rc);
         return rc;
@@ -214,7 +215,8 @@ static int fsp_page_reg_read(struct psmouse *psmouse, int *reg_val)
 
         ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE);
         psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
-        mutex_lock(&ps2dev->cmd_mutex);
+
+        ps2_begin_command(ps2dev);
 
         if (ps2_sendbyte(ps2dev, 0xf3, FSP_CMD_TIMEOUT) < 0)
                 goto out;
@@ -236,7 +238,7 @@ static int fsp_page_reg_read(struct psmouse *psmouse, int *reg_val)
         rc = 0;
 
  out:
-        mutex_unlock(&ps2dev->cmd_mutex);
+        ps2_end_command(ps2dev);
         ps2_command(ps2dev, NULL, PSMOUSE_CMD_ENABLE);
         psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
         dev_dbg(&ps2dev->serio->dev, "READ PAGE REG: 0x%02x (rc = %d)\n",
@@ -250,7 +252,7 @@ static int fsp_page_reg_write(struct psmouse *psmouse, int reg_val)
         unsigned char v;
         int rc = -1;
 
-        mutex_lock(&ps2dev->cmd_mutex);
+        ps2_begin_command(ps2dev);
 
         if (ps2_sendbyte(ps2dev, 0xf3, FSP_CMD_TIMEOUT) < 0)
                 goto out;
@@ -275,7 +277,7 @@ static int fsp_page_reg_write(struct psmouse *psmouse, int reg_val)
         rc = 0;
 
  out:
-        mutex_unlock(&ps2dev->cmd_mutex);
+        ps2_end_command(ps2dev);
         dev_dbg(&ps2dev->serio->dev, "WRITE PAGE REG: to 0x%02x (rc = %d)\n",
                 reg_val, rc);
         return rc;