diff options
author | Matthew Garrett <mjg@redhat.com> | 2009-12-12 01:00:57 -0500 |
---|---|---|
committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2009-12-12 02:55:42 -0500 |
commit | 967c9ef9b8c3bdec1bd3a380edac19e0b9fbeadc (patch) | |
tree | 03a3ba3fec91014adb5afbe78f40ffb429c3753e /drivers/input | |
parent | 4e8d340daac46cec8a0f8b3b0f228274fac913ba (diff) |
Input: i8042 - allow installing platform filters for incoming data
Some hardware (such as Dell laptops) signal a variety of events through
the i8042 controller, even if these don't map to keyboard events. Add
support for drivers to filter the i8042 event stream in order to respond
to these events and (if appropriate) block them from entering the input
stream.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Diffstat (limited to 'drivers/input')
-rw-r--r-- | drivers/input/serio/i8042.c | 58 |
1 files changed, 55 insertions, 3 deletions
diff --git a/drivers/input/serio/i8042.c b/drivers/input/serio/i8042.c index 634da68f7f35..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; | |||
126 | static struct platform_device *i8042_platform_device; | 126 | static struct platform_device *i8042_platform_device; |
127 | 127 | ||
128 | static irqreturn_t i8042_interrupt(int irq, void *dev_id); | 128 | static irqreturn_t i8042_interrupt(int irq, void *dev_id); |
129 | static bool (*i8042_platform_filter)(unsigned char data, unsigned char str, | ||
130 | struct serio *serio); | ||
129 | 131 | ||
130 | void i8042_lock_chip(void) | 132 | void i8042_lock_chip(void) |
131 | { | 133 | { |
@@ -139,6 +141,48 @@ void i8042_unlock_chip(void) | |||
139 | } | 141 | } |
140 | EXPORT_SYMBOL(i8042_unlock_chip); | 142 | EXPORT_SYMBOL(i8042_unlock_chip); |
141 | 143 | ||
144 | int i8042_install_filter(bool (*filter)(unsigned char data, unsigned char str, | ||
145 | struct serio *serio)) | ||
146 | { | ||
147 | unsigned long flags; | ||
148 | int ret = 0; | ||
149 | |||
150 | spin_lock_irqsave(&i8042_lock, flags); | ||
151 | |||
152 | if (i8042_platform_filter) { | ||
153 | ret = -EBUSY; | ||
154 | goto out; | ||
155 | } | ||
156 | |||
157 | i8042_platform_filter = filter; | ||
158 | |||
159 | out: | ||
160 | spin_unlock_irqrestore(&i8042_lock, flags); | ||
161 | return ret; | ||
162 | } | ||
163 | EXPORT_SYMBOL(i8042_install_filter); | ||
164 | |||
165 | int i8042_remove_filter(bool (*filter)(unsigned char data, unsigned char str, | ||
166 | struct serio *port)) | ||
167 | { | ||
168 | unsigned long flags; | ||
169 | int ret = 0; | ||
170 | |||
171 | spin_lock_irqsave(&i8042_lock, flags); | ||
172 | |||
173 | if (i8042_platform_filter != filter) { | ||
174 | ret = -EINVAL; | ||
175 | goto out; | ||
176 | } | ||
177 | |||
178 | i8042_platform_filter = NULL; | ||
179 | |||
180 | out: | ||
181 | spin_unlock_irqrestore(&i8042_lock, flags); | ||
182 | return ret; | ||
183 | } | ||
184 | EXPORT_SYMBOL(i8042_remove_filter); | ||
185 | |||
142 | /* | 186 | /* |
143 | * The i8042_wait_read() and i8042_wait_write functions wait for the i8042 to | 187 | * The i8042_wait_read() and i8042_wait_write functions wait for the i8042 to |
144 | * be ready for reading values from it / writing values to it. | 188 | * be ready for reading values from it / writing values to it. |
@@ -373,7 +417,8 @@ static void i8042_stop(struct serio *serio) | |||
373 | * It is called from i8042_interrupt and thus is running with interrupts | 417 | * It is called from i8042_interrupt and thus is running with interrupts |
374 | * off and i8042_lock held. | 418 | * off and i8042_lock held. |
375 | */ | 419 | */ |
376 | static bool i8042_filter(unsigned char data, unsigned char str) | 420 | static bool i8042_filter(unsigned char data, unsigned char str, |
421 | struct serio *serio) | ||
377 | { | 422 | { |
378 | if (unlikely(i8042_suppress_kbd_ack)) { | 423 | if (unlikely(i8042_suppress_kbd_ack)) { |
379 | if ((~str & I8042_STR_AUXDATA) && | 424 | if ((~str & I8042_STR_AUXDATA) && |
@@ -384,6 +429,11 @@ static bool i8042_filter(unsigned char data, unsigned char str) | |||
384 | } | 429 | } |
385 | } | 430 | } |
386 | 431 | ||
432 | if (i8042_platform_filter && i8042_platform_filter(data, str, serio)) { | ||
433 | dbg("Filtered out by platfrom filter\n"); | ||
434 | return true; | ||
435 | } | ||
436 | |||
387 | return false; | 437 | return false; |
388 | } | 438 | } |
389 | 439 | ||
@@ -396,6 +446,7 @@ static bool i8042_filter(unsigned char data, unsigned char str) | |||
396 | static irqreturn_t i8042_interrupt(int irq, void *dev_id) | 446 | static irqreturn_t i8042_interrupt(int irq, void *dev_id) |
397 | { | 447 | { |
398 | struct i8042_port *port; | 448 | struct i8042_port *port; |
449 | struct serio *serio; | ||
399 | unsigned long flags; | 450 | unsigned long flags; |
400 | unsigned char str, data; | 451 | unsigned char str, data; |
401 | unsigned int dfl; | 452 | unsigned int dfl; |
@@ -462,18 +513,19 @@ static irqreturn_t i8042_interrupt(int irq, void *dev_id) | |||
462 | } | 513 | } |
463 | 514 | ||
464 | port = &i8042_ports[port_no]; | 515 | port = &i8042_ports[port_no]; |
516 | serio = port->exists ? port->serio : NULL; | ||
465 | 517 | ||
466 | dbg("%02x <- i8042 (interrupt, %d, %d%s%s)", | 518 | dbg("%02x <- i8042 (interrupt, %d, %d%s%s)", |
467 | data, port_no, irq, | 519 | data, port_no, irq, |
468 | dfl & SERIO_PARITY ? ", bad parity" : "", | 520 | dfl & SERIO_PARITY ? ", bad parity" : "", |
469 | dfl & SERIO_TIMEOUT ? ", timeout" : ""); | 521 | dfl & SERIO_TIMEOUT ? ", timeout" : ""); |
470 | 522 | ||
471 | filtered = i8042_filter(data, str); | 523 | filtered = i8042_filter(data, str, serio); |
472 | 524 | ||
473 | spin_unlock_irqrestore(&i8042_lock, flags); | 525 | spin_unlock_irqrestore(&i8042_lock, flags); |
474 | 526 | ||
475 | if (likely(port->exists && !filtered)) | 527 | if (likely(port->exists && !filtered)) |
476 | serio_interrupt(port->serio, data, dfl); | 528 | serio_interrupt(serio, data, dfl); |
477 | 529 | ||
478 | out: | 530 | out: |
479 | return IRQ_RETVAL(ret); | 531 | return IRQ_RETVAL(ret); |