diff options
Diffstat (limited to 'drivers/input/serio/i8042.c')
| -rw-r--r-- | drivers/input/serio/i8042.c | 123 |
1 files changed, 107 insertions, 16 deletions
diff --git a/drivers/input/serio/i8042.c b/drivers/input/serio/i8042.c index a31578170ccc..d84a36e545f6 100644 --- a/drivers/input/serio/i8042.c +++ b/drivers/input/serio/i8042.c @@ -126,6 +126,8 @@ static unsigned char i8042_suppress_kbd_ack; static struct platform_device *i8042_platform_device; static irqreturn_t i8042_interrupt(int irq, void *dev_id); +static bool (*i8042_platform_filter)(unsigned char data, unsigned char str, + struct serio *serio); void i8042_lock_chip(void) { @@ -139,6 +141,48 @@ void i8042_unlock_chip(void) } EXPORT_SYMBOL(i8042_unlock_chip); +int i8042_install_filter(bool (*filter)(unsigned char data, unsigned char str, + struct serio *serio)) +{ + unsigned long flags; + int ret = 0; + + spin_lock_irqsave(&i8042_lock, flags); + + if (i8042_platform_filter) { + ret = -EBUSY; + goto out; + } + + i8042_platform_filter = filter; + +out: + spin_unlock_irqrestore(&i8042_lock, flags); + return ret; +} +EXPORT_SYMBOL(i8042_install_filter); + +int i8042_remove_filter(bool (*filter)(unsigned char data, unsigned char str, + struct serio *port)) +{ + unsigned long flags; + int ret = 0; + + spin_lock_irqsave(&i8042_lock, flags); + + if (i8042_platform_filter != filter) { + ret = -EINVAL; + goto out; + } + + i8042_platform_filter = NULL; + +out: + spin_unlock_irqrestore(&i8042_lock, flags); + return ret; +} +EXPORT_SYMBOL(i8042_remove_filter); + /* * The i8042_wait_read() and i8042_wait_write functions wait for the i8042 to * be ready for reading values from it / writing values to it. @@ -369,6 +413,31 @@ static void i8042_stop(struct serio *serio) } /* + * i8042_filter() filters out unwanted bytes from the input data stream. + * It is called from i8042_interrupt and thus is running with interrupts + * off and i8042_lock held. + */ +static bool i8042_filter(unsigned char data, unsigned char str, + struct serio *serio) +{ + if (unlikely(i8042_suppress_kbd_ack)) { + if ((~str & I8042_STR_AUXDATA) && + (data == 0xfa || data == 0xfe)) { + i8042_suppress_kbd_ack--; + dbg("Extra keyboard ACK - filtered out\n"); + return true; + } + } + + if (i8042_platform_filter && i8042_platform_filter(data, str, serio)) { + dbg("Filtered out by platfrom filter\n"); + return true; + } + + return false; +} + +/* * i8042_interrupt() is the most important function in this driver - * it handles the interrupts from the i8042, and sends incoming bytes * to the upper layers. @@ -377,13 +446,16 @@ static void i8042_stop(struct serio *serio) static irqreturn_t i8042_interrupt(int irq, void *dev_id) { struct i8042_port *port; + struct serio *serio; unsigned long flags; unsigned char str, data; unsigned int dfl; unsigned int port_no; + bool filtered; int ret = 1; spin_lock_irqsave(&i8042_lock, flags); + str = i8042_read_status(); if (unlikely(~str & I8042_STR_OBF)) { spin_unlock_irqrestore(&i8042_lock, flags); @@ -391,8 +463,8 @@ static irqreturn_t i8042_interrupt(int irq, void *dev_id) ret = 0; goto out; } + data = i8042_read_data(); - spin_unlock_irqrestore(&i8042_lock, flags); if (i8042_mux_present && (str & I8042_STR_AUXDATA)) { static unsigned long last_transmit; @@ -441,21 +513,19 @@ static irqreturn_t i8042_interrupt(int irq, void *dev_id) } port = &i8042_ports[port_no]; + serio = port->exists ? port->serio : NULL; dbg("%02x <- i8042 (interrupt, %d, %d%s%s)", data, port_no, irq, dfl & SERIO_PARITY ? ", bad parity" : "", dfl & SERIO_TIMEOUT ? ", timeout" : ""); - if (unlikely(i8042_suppress_kbd_ack)) - if (port_no == I8042_KBD_PORT_NO && - (data == 0xfa || data == 0xfe)) { - i8042_suppress_kbd_ack--; - goto out; - } + filtered = i8042_filter(data, str, serio); + + spin_unlock_irqrestore(&i8042_lock, flags); - if (likely(port->exists)) - serio_interrupt(port->serio, data, dfl); + if (likely(port->exists && !filtered)) + serio_interrupt(serio, data, dfl); out: return IRQ_RETVAL(ret); @@ -836,17 +906,32 @@ static int i8042_controller_selftest(void) static int i8042_controller_init(void) { unsigned long flags; + int n = 0; + unsigned char ctr[2]; /* - * Save the CTR for restoral on unload / reboot. + * Save the CTR for restore on unload / reboot. */ - if (i8042_command(&i8042_ctr, I8042_CMD_CTL_RCTR)) { - printk(KERN_ERR "i8042.c: Can't read CTR while initializing i8042.\n"); - return -EIO; - } + do { + if (n >= 10) { + printk(KERN_ERR + "i8042.c: Unable to get stable CTR read.\n"); + return -EIO; + } + + if (n != 0) + udelay(50); + + if (i8042_command(&ctr[n++ % 2], I8042_CMD_CTL_RCTR)) { + printk(KERN_ERR + "i8042.c: Can't read CTR while initializing i8042.\n"); + return -EIO; + } - i8042_initial_ctr = i8042_ctr; + } while (n < 2 || ctr[0] != ctr[1]); + + i8042_initial_ctr = i8042_ctr = ctr[0]; /* * Disable the keyboard interface and interrupt. @@ -895,6 +980,12 @@ static int i8042_controller_init(void) return -EIO; } +/* + * Flush whatever accumulated while we were disabling keyboard port. + */ + + i8042_flush(); + return 0; } @@ -914,7 +1005,7 @@ static void i8042_controller_reset(void) i8042_ctr |= I8042_CTR_KBDDIS | I8042_CTR_AUXDIS; i8042_ctr &= ~(I8042_CTR_KBDINT | I8042_CTR_AUXINT); - if (i8042_command(&i8042_initial_ctr, I8042_CMD_CTL_WCTR)) + if (i8042_command(&i8042_ctr, I8042_CMD_CTL_WCTR)) printk(KERN_WARNING "i8042.c: Can't write CTR while resetting.\n"); /* |