diff options
| author | Roland Scheidegger <sroland@tungstengraphics.com> | 2007-05-08 09:31:40 +0400 |
|---|---|---|
| committer | Dmitry Torokhov <dtor@insightbb.com> | 2007-05-08 09:31:40 +0400 |
| commit | d2ada5597d33a9108acb2caf912f85cbc9caab1e (patch) | |
| tree | c8fe7ebaf381f6874e768b21f978bff887137852 /drivers | |
| parent | 334d0dd8b660557608142f0f77abc6812b48f08b (diff) | |
| download | linux-d2ada5597d33a9108acb2caf912f85cbc9caab1e.tar.xz | |
Input: i8042 - fix AUX port detection with some chips
The i8042 driver fails detection of the AUX port with some chips,
because they apparently do not change the I8042_CTR_AUXDIS bit
immediately. This is known to affect at least HP500/HP510 notebooks,
consequently the built-in touchpad will not work. The patch will simply
reread the value until it gets the expected value or a retry limit is
hit, without touching other workaround code in the same area.
Signed-off-by: Roland Scheidegger <sroland@tungstengraphics.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/input/serio/i8042.c | 35 |
1 files changed, 29 insertions, 6 deletions
diff --git a/drivers/input/serio/i8042.c b/drivers/input/serio/i8042.c index 7c17377a65b9..3888dc307e0c 100644 --- a/drivers/input/serio/i8042.c +++ b/drivers/input/serio/i8042.c @@ -526,6 +526,33 @@ static irqreturn_t __devinit i8042_aux_test_irq(int irq, void *dev_id) return IRQ_HANDLED; } +/* + * i8042_toggle_aux - enables or disables AUX port on i8042 via command and + * verifies success by readinng CTR. Used when testing for presence of AUX + * port. + */ +static int __devinit i8042_toggle_aux(int on) +{ + unsigned char param; + int i; + + if (i8042_command(¶m, + on ? I8042_CMD_AUX_ENABLE : I8042_CMD_AUX_DISABLE)) + return -1; + + /* some chips need some time to set the I8042_CTR_AUXDIS bit */ + for (i = 0; i < 100; i++) { + udelay(50); + + if (i8042_command(¶m, I8042_CMD_CTL_RCTR)) + return -1; + + if (!(param & I8042_CTR_AUXDIS) == on) + return 0; + } + + return -1; +} /* * i8042_check_aux() applies as much paranoia as it can at detecting @@ -580,16 +607,12 @@ static int __devinit i8042_check_aux(void) * Bit assignment test - filters out PS/2 i8042's in AT mode */ - if (i8042_command(¶m, I8042_CMD_AUX_DISABLE)) - return -1; - if (i8042_command(¶m, I8042_CMD_CTL_RCTR) || (~param & I8042_CTR_AUXDIS)) { + if (i8042_toggle_aux(0)) { printk(KERN_WARNING "Failed to disable AUX port, but continuing anyway... Is this a SiS?\n"); printk(KERN_WARNING "If AUX port is really absent please use the 'i8042.noaux' option.\n"); } - if (i8042_command(¶m, I8042_CMD_AUX_ENABLE)) - return -1; - if (i8042_command(¶m, I8042_CMD_CTL_RCTR) || (param & I8042_CTR_AUXDIS)) + if (i8042_toggle_aux(1)) return -1; /* |