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author | Jiri Slaby <jslaby@suse.cz> | 2012-03-05 14:52:17 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-03-08 12:27:57 -0800 |
commit | 964105b501071e8a0e9feb1d0e4b3e46508bc38e (patch) | |
tree | e312158b9f0ffdb4c6ad46d554593b70e3092114 /arch/ia64 | |
parent | d852256389f1bcf506710ea5de77debde40013b9 (diff) | |
download | linux-stable-964105b501071e8a0e9feb1d0e4b3e46508bc38e.tar.gz linux-stable-964105b501071e8a0e9feb1d0e4b3e46508bc38e.tar.bz2 linux-stable-964105b501071e8a0e9feb1d0e4b3e46508bc38e.zip |
TTY: simserial, remove support of shared interrupts
It never worked there. The ISR was never written for that kind of
stuff. So remove all that crap with a hash of linked lists and pass
the pointer directly to the ISR.
BTW this answers the question there:
* I don't know exactly why they don't use the dev_id opaque data
* pointer instead of this extra lookup table
-> Because they thought they will support more devices bound to a
single interrupt w/o IRQF_SHARED. They would need exactly the hash
there.
What I don't understand is rebinding of the interrupt in the shutdown
path. They perhaps meant to do just synchronize_irq? In any case, this
is all gone and free_irq there properly.
By removing the hash we save some bits (exactly NR_IRQS * 8 bytes of
.bss and over a kilo of .text):
before:
text data bss dec hex filename
19600 320 8227 28147 6df3 ../a/ia64/arch/ia64/hp/sim/simserial.o
after:
text data bss dec hex filename
18568 320 28 18916 49e4 ../a/ia64/arch/ia64/hp/sim/simserial.o
Note that a shared interrupt could not work too. request_irq requires
data parameter to be non-NULL. So the whole IRQ_T exercise was
pointless.
Finally, this helps us remove another two members of async_struct :).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/ia64')
-rw-r--r-- | arch/ia64/hp/sim/simserial.c | 64 |
1 files changed, 7 insertions, 57 deletions
diff --git a/arch/ia64/hp/sim/simserial.c b/arch/ia64/hp/sim/simserial.c index d32b759b23f1..c35552df035e 100644 --- a/arch/ia64/hp/sim/simserial.c +++ b/arch/ia64/hp/sim/simserial.c @@ -92,8 +92,6 @@ static struct serial_uart_config uart_config[] = { struct tty_driver *hp_simserial_driver; -static struct async_struct *IRQ_ports[NR_IRQS]; - static struct console *console; static unsigned char *tmp_buf; @@ -167,14 +165,9 @@ static void receive_chars(struct tty_struct *tty) */ static irqreturn_t rs_interrupt_single(int irq, void *dev_id) { - struct async_struct * info; + struct async_struct *info = dev_id; - /* - * I don't know exactly why they don't use the dev_id opaque data - * pointer instead of this extra lookup table - */ - info = IRQ_ports[irq]; - if (!info || !info->tty) { + if (!info->tty) { printk(KERN_INFO "simrs_interrupt_single: info|tty=0 info=%p problem\n", info); return IRQ_NONE; } @@ -456,7 +449,6 @@ static void shutdown(struct async_struct * info) { unsigned long flags; struct serial_state *state = info->state; - int retval; if (!(state->flags & ASYNC_INITIALIZED)) return; @@ -468,33 +460,8 @@ static void shutdown(struct async_struct * info) local_irq_save(flags); { - /* - * First unlink the serial port from the IRQ chain... - */ - if (info->next_port) - info->next_port->prev_port = info->prev_port; - if (info->prev_port) - info->prev_port->next_port = info->next_port; - else - IRQ_ports[state->irq] = info->next_port; - - /* - * Free the IRQ, if necessary - */ - if (state->irq && (!IRQ_ports[state->irq] || - !IRQ_ports[state->irq]->next_port)) { - if (IRQ_ports[state->irq]) { - free_irq(state->irq, NULL); - retval = request_irq(state->irq, rs_interrupt_single, - IRQ_T(state), "serial", - NULL); - - if (retval) - printk(KERN_ERR "serial shutdown: request_irq: error %d" - " Couldn't reacquire IRQ.\n", retval); - } else - free_irq(state->irq, NULL); - } + if (state->irq) + free_irq(state->irq, info); if (info->xmit.buf) { free_page((unsigned long) info->xmit.buf); @@ -645,7 +612,6 @@ startup(struct async_struct *info) { unsigned long flags; int retval=0; - irq_handler_t handler; struct serial_state *state= info->state; unsigned long page; @@ -677,29 +643,13 @@ startup(struct async_struct *info) /* * Allocate the IRQ if necessary */ - if (state->irq && (!IRQ_ports[state->irq] || - !IRQ_ports[state->irq]->next_port)) { - if (IRQ_ports[state->irq]) { - retval = -EBUSY; - goto errout; - } else - handler = rs_interrupt_single; - - retval = request_irq(state->irq, handler, IRQ_T(state), - "simserial", NULL); + if (state->irq) { + retval = request_irq(state->irq, rs_interrupt_single, + IRQ_T(state), "simserial", info); if (retval) goto errout; } - /* - * Insert serial port into IRQ chain. - */ - info->prev_port = NULL; - info->next_port = IRQ_ports[state->irq]; - if (info->next_port) - info->next_port->prev_port = info; - IRQ_ports[state->irq] = info; - if (info->tty) clear_bit(TTY_IO_ERROR, &info->tty->flags); info->xmit.head = info->xmit.tail = 0; |