2014-08-15 08:01:23 +00:00
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/*
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2014-08-15 11:44:32 +00:00
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* UART driver for the Greybus "generic" UART module.
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2014-08-15 08:01:23 +00:00
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*
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* Copyright 2014 Google Inc.
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*
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* Released under the GPLv2 only.
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2014-08-15 11:44:32 +00:00
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*
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* Heavily based on drivers/usb/class/cdc-acm.c and
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* drivers/usb/serial/usb-serial.c.
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2014-08-15 08:01:23 +00:00
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*/
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2014-09-13 23:15:52 +00:00
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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2014-08-15 08:01:23 +00:00
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#include <linux/kernel.h>
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2014-08-15 11:44:32 +00:00
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#include <linux/errno.h>
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2014-08-15 08:01:23 +00:00
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#include <linux/module.h>
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2014-08-15 11:44:32 +00:00
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#include <linux/sched.h>
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#include <linux/wait.h>
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2014-08-15 08:01:23 +00:00
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#include <linux/slab.h>
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2014-08-15 11:44:32 +00:00
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#include <linux/uaccess.h>
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#include <linux/mutex.h>
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2014-08-15 08:01:23 +00:00
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#include <linux/tty.h>
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#include <linux/serial.h>
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#include <linux/tty_driver.h>
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#include <linux/tty_flip.h>
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2014-08-15 11:44:32 +00:00
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#include <linux/serial.h>
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2014-08-15 10:33:33 +00:00
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#include <linux/idr.h>
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2014-09-06 03:56:10 +00:00
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#include <linux/fs.h>
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#include <linux/kdev_t.h>
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2014-08-15 08:01:23 +00:00
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#include "greybus.h"
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2014-08-15 10:54:11 +00:00
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#define GB_NUM_MINORS 255 /* 255 is enough for anyone... */
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2014-09-06 03:56:10 +00:00
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#define GB_NAME "ttyGB"
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2014-08-15 08:01:23 +00:00
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struct gb_tty {
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struct tty_port port;
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struct greybus_device *gdev;
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int cport;
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unsigned int minor;
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unsigned char clocal;
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2014-08-15 10:54:11 +00:00
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unsigned int throttled:1;
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unsigned int throttle_req:1;
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2014-08-15 11:44:32 +00:00
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bool disconnected;
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int writesize; // FIXME - set this somehow.
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2014-08-15 10:54:11 +00:00
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spinlock_t read_lock;
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spinlock_t write_lock;
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2014-08-15 11:44:32 +00:00
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struct async_icount iocount;
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struct async_icount oldcount;
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wait_queue_head_t wioctl;
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struct mutex mutex;
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2014-08-15 08:01:23 +00:00
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};
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2014-09-01 20:31:31 +00:00
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static const struct greybus_module_id id_table[] = {
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2014-08-15 08:01:23 +00:00
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{ GREYBUS_DEVICE(0x45, 0x45) }, /* make shit up */
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{ }, /* terminating NULL entry */
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};
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2014-08-15 10:33:33 +00:00
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static struct tty_driver *gb_tty_driver;
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static DEFINE_IDR(tty_minors);
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static DEFINE_MUTEX(table_lock);
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static struct gb_tty *get_gb_by_minor(unsigned minor)
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{
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struct gb_tty *gb_tty;
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mutex_lock(&table_lock);
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gb_tty = idr_find(&tty_minors, minor);
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2014-08-15 11:44:32 +00:00
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if (gb_tty) {
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mutex_lock(&gb_tty->mutex);
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if (gb_tty->disconnected) {
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mutex_unlock(&gb_tty->mutex);
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gb_tty = NULL;
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} else {
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tty_port_get(&gb_tty->port);
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mutex_unlock(&gb_tty->mutex);
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}
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}
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2014-08-15 10:33:33 +00:00
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mutex_unlock(&table_lock);
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return gb_tty;
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}
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static int alloc_minor(struct gb_tty *gb_tty)
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{
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int minor;
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mutex_lock(&table_lock);
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greybus: uart-gb: improve minor device number error checking
When alloc_minor() finds an available minor device number it
does not constrain the highest number desired. Instead, it
relies on its caller, tty_gb_probe() to see if the returned
number indicates all minor numbers have been exhausted.
There are a couple problems with this--or rather with this
code.
First, if an allocation is attempted *after* GB_NUM_MINORS
is returned, a new number greater than (but not equal to)
GB_NUM_MINORS will be allocated, and that won't produce
any error condition.
Second, alloc_minor() can return an error code (like -ENOMEM). And
its caller is only checking for GB_NUM_MINORS. If an error code
is returned, tty_gb_probe() simply uses it.
Change alloc_minor() so it requests minor device numbers in the
range 0..(GB_NUM_MINORS-1), and use an error return to detect
when the minor device numbers have been exhausted.
If alloc_minor() returns -ENOSPC (from idr_alloc()), translate that
to -ENODEV. The only other error we might see is -ENOMEM, and if
we get that, return it.
Finally, zero gb_tty->minor when it's released. (If this is
actually important a reserved value like GB_NUM_MINORS should
be used instead to signify a gb_tty with no minor assigned.)
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-08-18 23:25:11 +00:00
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minor = idr_alloc(&tty_minors, gb_tty, 0, GB_NUM_MINORS, GFP_KERNEL);
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2014-08-15 10:33:33 +00:00
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mutex_unlock(&table_lock);
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greybus: uart-gb: improve minor device number error checking
When alloc_minor() finds an available minor device number it
does not constrain the highest number desired. Instead, it
relies on its caller, tty_gb_probe() to see if the returned
number indicates all minor numbers have been exhausted.
There are a couple problems with this--or rather with this
code.
First, if an allocation is attempted *after* GB_NUM_MINORS
is returned, a new number greater than (but not equal to)
GB_NUM_MINORS will be allocated, and that won't produce
any error condition.
Second, alloc_minor() can return an error code (like -ENOMEM). And
its caller is only checking for GB_NUM_MINORS. If an error code
is returned, tty_gb_probe() simply uses it.
Change alloc_minor() so it requests minor device numbers in the
range 0..(GB_NUM_MINORS-1), and use an error return to detect
when the minor device numbers have been exhausted.
If alloc_minor() returns -ENOSPC (from idr_alloc()), translate that
to -ENODEV. The only other error we might see is -ENOMEM, and if
we get that, return it.
Finally, zero gb_tty->minor when it's released. (If this is
actually important a reserved value like GB_NUM_MINORS should
be used instead to signify a gb_tty with no minor assigned.)
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-08-18 23:25:11 +00:00
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if (minor >= 0)
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gb_tty->minor = minor;
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2014-08-15 10:33:33 +00:00
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return minor;
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}
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static void release_minor(struct gb_tty *gb_tty)
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{
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greybus: uart-gb: improve minor device number error checking
When alloc_minor() finds an available minor device number it
does not constrain the highest number desired. Instead, it
relies on its caller, tty_gb_probe() to see if the returned
number indicates all minor numbers have been exhausted.
There are a couple problems with this--or rather with this
code.
First, if an allocation is attempted *after* GB_NUM_MINORS
is returned, a new number greater than (but not equal to)
GB_NUM_MINORS will be allocated, and that won't produce
any error condition.
Second, alloc_minor() can return an error code (like -ENOMEM). And
its caller is only checking for GB_NUM_MINORS. If an error code
is returned, tty_gb_probe() simply uses it.
Change alloc_minor() so it requests minor device numbers in the
range 0..(GB_NUM_MINORS-1), and use an error return to detect
when the minor device numbers have been exhausted.
If alloc_minor() returns -ENOSPC (from idr_alloc()), translate that
to -ENODEV. The only other error we might see is -ENOMEM, and if
we get that, return it.
Finally, zero gb_tty->minor when it's released. (If this is
actually important a reserved value like GB_NUM_MINORS should
be used instead to signify a gb_tty with no minor assigned.)
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-08-18 23:25:11 +00:00
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int minor = gb_tty->minor;
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gb_tty->minor = 0; /* Maybe should use an invalid value instead */
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2014-08-15 10:33:33 +00:00
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mutex_lock(&table_lock);
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greybus: uart-gb: improve minor device number error checking
When alloc_minor() finds an available minor device number it
does not constrain the highest number desired. Instead, it
relies on its caller, tty_gb_probe() to see if the returned
number indicates all minor numbers have been exhausted.
There are a couple problems with this--or rather with this
code.
First, if an allocation is attempted *after* GB_NUM_MINORS
is returned, a new number greater than (but not equal to)
GB_NUM_MINORS will be allocated, and that won't produce
any error condition.
Second, alloc_minor() can return an error code (like -ENOMEM). And
its caller is only checking for GB_NUM_MINORS. If an error code
is returned, tty_gb_probe() simply uses it.
Change alloc_minor() so it requests minor device numbers in the
range 0..(GB_NUM_MINORS-1), and use an error return to detect
when the minor device numbers have been exhausted.
If alloc_minor() returns -ENOSPC (from idr_alloc()), translate that
to -ENODEV. The only other error we might see is -ENOMEM, and if
we get that, return it.
Finally, zero gb_tty->minor when it's released. (If this is
actually important a reserved value like GB_NUM_MINORS should
be used instead to signify a gb_tty with no minor assigned.)
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-08-18 23:25:11 +00:00
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idr_remove(&tty_minors, minor);
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2014-08-15 10:33:33 +00:00
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mutex_unlock(&table_lock);
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}
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static int gb_tty_install(struct tty_driver *driver, struct tty_struct *tty)
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{
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struct gb_tty *gb_tty;
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int retval;
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gb_tty = get_gb_by_minor(tty->index);
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if (!gb_tty)
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return -ENODEV;
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retval = tty_standard_install(driver, tty);
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if (retval)
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goto error;
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tty->driver_data = gb_tty;
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return 0;
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error:
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tty_port_put(&gb_tty->port);
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return retval;
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}
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static int gb_tty_open(struct tty_struct *tty, struct file *file)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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return tty_port_open(&gb_tty->port, tty, file);
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}
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static void gb_tty_close(struct tty_struct *tty, struct file *file)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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tty_port_close(&gb_tty->port, tty, file);
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}
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static void gb_tty_cleanup(struct tty_struct *tty)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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tty_port_put(&gb_tty->port);
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}
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static void gb_tty_hangup(struct tty_struct *tty)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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tty_port_hangup(&gb_tty->port);
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}
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2014-08-15 10:54:11 +00:00
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static int gb_tty_write(struct tty_struct *tty, const unsigned char *buf,
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int count)
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{
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2014-08-15 11:44:32 +00:00
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// struct gb_tty *gb_tty = tty->driver_data;
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2014-08-15 10:54:11 +00:00
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// FIXME - actually implement...
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return 0;
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}
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static int gb_tty_write_room(struct tty_struct *tty)
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{
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2014-08-15 11:44:32 +00:00
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// struct gb_tty *gb_tty = tty->driver_data;
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2014-08-15 10:54:11 +00:00
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// FIXME - how much do we want to say we have room for?
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return 0;
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}
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static int gb_tty_chars_in_buffer(struct tty_struct *tty)
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{
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2014-08-15 11:44:32 +00:00
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// struct gb_tty *gb_tty = tty->driver_data;
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2014-08-15 10:54:11 +00:00
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// FIXME - how many left to send?
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return 0;
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}
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2014-08-15 11:44:32 +00:00
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static int gb_tty_break_ctl(struct tty_struct *tty, int state)
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{
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// struct gb_tty *gb_tty = tty->driver_data;
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// FIXME - send a break, if asked to...
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return 0;
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}
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static void gb_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
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{
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// FIXME - is this it???
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tty_termios_copy_hw(&tty->termios, old);
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}
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static int gb_tty_tiocmget(struct tty_struct *tty)
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{
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// struct gb_tty *gb_tty = tty->driver_data;
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// FIXME - get some tiocms!
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return 0;
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}
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static int gb_tty_tiocmset(struct tty_struct *tty, unsigned int set,
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unsigned int clear)
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{
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// struct gb_tty *gb_tty = tty->driver_data;
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// FIXME - set some tiocms!
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return 0;
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}
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2014-08-15 10:54:11 +00:00
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static void gb_tty_throttle(struct tty_struct *tty)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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spin_lock_irq(&gb_tty->read_lock);
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gb_tty->throttle_req = 1;
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spin_unlock_irq(&gb_tty->read_lock);
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}
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static void gb_tty_unthrottle(struct tty_struct *tty)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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unsigned int was_throttled;
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spin_lock_irq(&gb_tty->read_lock);
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was_throttled = gb_tty->throttled;
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gb_tty->throttle_req = 0;
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gb_tty->throttled = 0;
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spin_unlock_irq(&gb_tty->read_lock);
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if (was_throttled) {
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// FIXME - send more data
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}
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}
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2014-08-15 11:44:32 +00:00
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static int get_serial_info(struct gb_tty *gb_tty,
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struct serial_struct __user *info)
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{
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struct serial_struct tmp;
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if (!info)
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return -EINVAL;
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memset(&tmp, 0, sizeof(tmp));
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tmp.flags = ASYNC_LOW_LATENCY;
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tmp.xmit_fifo_size = gb_tty->writesize;
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tmp.baud_base = 0; // FIXME
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tmp.close_delay = gb_tty->port.close_delay / 10;
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tmp.closing_wait = gb_tty->port.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
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ASYNC_CLOSING_WAIT_NONE : gb_tty->port.closing_wait / 10;
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if (copy_to_user(info, &tmp, sizeof(tmp)))
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return -EFAULT;
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2014-09-02 02:10:06 +00:00
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return 0;
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2014-08-15 11:44:32 +00:00
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}
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static int set_serial_info(struct gb_tty *gb_tty,
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struct serial_struct __user *newinfo)
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{
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struct serial_struct new_serial;
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unsigned int closing_wait;
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unsigned int close_delay;
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int retval;
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if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
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return -EFAULT;
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close_delay = new_serial.close_delay * 10;
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closing_wait = new_serial.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
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ASYNC_CLOSING_WAIT_NONE : new_serial.closing_wait * 10;
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mutex_lock(&gb_tty->port.mutex);
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if (!capable(CAP_SYS_ADMIN)) {
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if ((close_delay != gb_tty->port.close_delay) ||
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|
|
(closing_wait != gb_tty->port.closing_wait))
|
|
|
|
retval = -EPERM;
|
|
|
|
else
|
|
|
|
retval = -EOPNOTSUPP;
|
|
|
|
} else {
|
|
|
|
gb_tty->port.close_delay = close_delay;
|
|
|
|
gb_tty->port.closing_wait = closing_wait;
|
|
|
|
}
|
|
|
|
mutex_unlock(&gb_tty->port.mutex);
|
|
|
|
return retval;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int wait_serial_change(struct gb_tty *gb_tty, unsigned long arg)
|
|
|
|
{
|
|
|
|
int retval = 0;
|
|
|
|
DECLARE_WAITQUEUE(wait, current);
|
|
|
|
struct async_icount old;
|
|
|
|
struct async_icount new;
|
|
|
|
|
2014-08-18 23:25:12 +00:00
|
|
|
if (!(arg & (TIOCM_DSR | TIOCM_RI | TIOCM_CD)))
|
2014-08-15 11:44:32 +00:00
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
do {
|
|
|
|
spin_lock_irq(&gb_tty->read_lock);
|
|
|
|
old = gb_tty->oldcount;
|
|
|
|
new = gb_tty->iocount;
|
|
|
|
gb_tty->oldcount = new;
|
2014-08-18 23:25:12 +00:00
|
|
|
spin_unlock_irq(&gb_tty->read_lock);
|
2014-08-15 11:44:32 +00:00
|
|
|
|
|
|
|
if ((arg & TIOCM_DSR) && (old.dsr != new.dsr))
|
|
|
|
break;
|
|
|
|
if ((arg & TIOCM_CD) && (old.dcd != new.dcd))
|
|
|
|
break;
|
|
|
|
if ((arg & TIOCM_RI) && (old.rng != new.rng))
|
|
|
|
break;
|
|
|
|
|
|
|
|
add_wait_queue(&gb_tty->wioctl, &wait);
|
|
|
|
set_current_state(TASK_INTERRUPTIBLE);
|
|
|
|
schedule();
|
|
|
|
remove_wait_queue(&gb_tty->wioctl, &wait);
|
|
|
|
if (gb_tty->disconnected) {
|
|
|
|
if (arg & TIOCM_CD)
|
|
|
|
break;
|
2014-08-18 23:25:12 +00:00
|
|
|
retval = -ENODEV;
|
|
|
|
} else if (signal_pending(current)) {
|
|
|
|
retval = -ERESTARTSYS;
|
2014-08-15 11:44:32 +00:00
|
|
|
}
|
|
|
|
} while (!retval);
|
|
|
|
|
|
|
|
return retval;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int get_serial_usage(struct gb_tty *gb_tty,
|
|
|
|
struct serial_icounter_struct __user *count)
|
|
|
|
{
|
|
|
|
struct serial_icounter_struct icount;
|
|
|
|
int retval = 0;
|
|
|
|
|
|
|
|
memset(&icount, 0, sizeof(icount));
|
|
|
|
icount.dsr = gb_tty->iocount.dsr;
|
|
|
|
icount.rng = gb_tty->iocount.rng;
|
|
|
|
icount.dcd = gb_tty->iocount.dcd;
|
|
|
|
icount.frame = gb_tty->iocount.frame;
|
|
|
|
icount.overrun = gb_tty->iocount.overrun;
|
|
|
|
icount.parity = gb_tty->iocount.parity;
|
|
|
|
icount.brk = gb_tty->iocount.brk;
|
|
|
|
|
|
|
|
if (copy_to_user(count, &icount, sizeof(icount)) > 0)
|
|
|
|
retval = -EFAULT;
|
|
|
|
|
|
|
|
return retval;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int gb_tty_ioctl(struct tty_struct *tty, unsigned int cmd,
|
|
|
|
unsigned long arg)
|
|
|
|
{
|
|
|
|
struct gb_tty *gb_tty = tty->driver_data;
|
|
|
|
|
|
|
|
switch (cmd) {
|
|
|
|
case TIOCGSERIAL:
|
2014-08-30 23:20:22 +00:00
|
|
|
return get_serial_info(gb_tty,
|
|
|
|
(struct serial_struct __user *)arg);
|
2014-08-15 11:44:32 +00:00
|
|
|
case TIOCSSERIAL:
|
2014-08-30 23:20:22 +00:00
|
|
|
return set_serial_info(gb_tty,
|
|
|
|
(struct serial_struct __user *)arg);
|
2014-08-15 11:44:32 +00:00
|
|
|
case TIOCMIWAIT:
|
2014-08-30 23:20:22 +00:00
|
|
|
return wait_serial_change(gb_tty, arg);
|
2014-08-15 11:44:32 +00:00
|
|
|
case TIOCGICOUNT:
|
2014-08-30 23:20:22 +00:00
|
|
|
return get_serial_usage(gb_tty,
|
|
|
|
(struct serial_icounter_struct __user *)arg);
|
2014-08-15 11:44:32 +00:00
|
|
|
}
|
|
|
|
|
2014-08-30 23:20:22 +00:00
|
|
|
return -ENOIOCTLCMD;
|
2014-08-15 11:44:32 +00:00
|
|
|
}
|
|
|
|
|
2014-08-15 08:01:23 +00:00
|
|
|
|
|
|
|
static const struct tty_operations gb_ops = {
|
|
|
|
.install = gb_tty_install,
|
|
|
|
.open = gb_tty_open,
|
|
|
|
.close = gb_tty_close,
|
|
|
|
.cleanup = gb_tty_cleanup,
|
|
|
|
.hangup = gb_tty_hangup,
|
|
|
|
.write = gb_tty_write,
|
|
|
|
.write_room = gb_tty_write_room,
|
|
|
|
.ioctl = gb_tty_ioctl,
|
|
|
|
.throttle = gb_tty_throttle,
|
|
|
|
.unthrottle = gb_tty_unthrottle,
|
|
|
|
.chars_in_buffer = gb_tty_chars_in_buffer,
|
|
|
|
.break_ctl = gb_tty_break_ctl,
|
|
|
|
.set_termios = gb_tty_set_termios,
|
|
|
|
.tiocmget = gb_tty_tiocmget,
|
|
|
|
.tiocmset = gb_tty_tiocmset,
|
|
|
|
};
|
|
|
|
|
|
|
|
|
2014-08-30 23:47:26 +00:00
|
|
|
int gb_tty_probe(struct greybus_device *gdev,
|
2014-09-01 20:31:31 +00:00
|
|
|
const struct greybus_module_id *id)
|
2014-08-15 08:01:23 +00:00
|
|
|
{
|
2014-08-15 10:54:11 +00:00
|
|
|
struct gb_tty *gb_tty;
|
|
|
|
struct device *tty_dev;
|
2014-08-15 08:01:23 +00:00
|
|
|
int retval;
|
2014-08-15 10:54:11 +00:00
|
|
|
int minor;
|
|
|
|
|
2014-08-31 00:18:04 +00:00
|
|
|
gb_tty = kzalloc(sizeof(*gb_tty), GFP_KERNEL);
|
2014-08-15 10:54:11 +00:00
|
|
|
if (!gb_tty)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
|
|
|
minor = alloc_minor(gb_tty);
|
greybus: uart-gb: improve minor device number error checking
When alloc_minor() finds an available minor device number it
does not constrain the highest number desired. Instead, it
relies on its caller, tty_gb_probe() to see if the returned
number indicates all minor numbers have been exhausted.
There are a couple problems with this--or rather with this
code.
First, if an allocation is attempted *after* GB_NUM_MINORS
is returned, a new number greater than (but not equal to)
GB_NUM_MINORS will be allocated, and that won't produce
any error condition.
Second, alloc_minor() can return an error code (like -ENOMEM). And
its caller is only checking for GB_NUM_MINORS. If an error code
is returned, tty_gb_probe() simply uses it.
Change alloc_minor() so it requests minor device numbers in the
range 0..(GB_NUM_MINORS-1), and use an error return to detect
when the minor device numbers have been exhausted.
If alloc_minor() returns -ENOSPC (from idr_alloc()), translate that
to -ENODEV. The only other error we might see is -ENOMEM, and if
we get that, return it.
Finally, zero gb_tty->minor when it's released. (If this is
actually important a reserved value like GB_NUM_MINORS should
be used instead to signify a gb_tty with no minor assigned.)
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-08-18 23:25:11 +00:00
|
|
|
if (minor < 0) {
|
|
|
|
if (minor == -ENOSPC) {
|
|
|
|
dev_err(&gdev->dev, "no more free minor numbers\n");
|
|
|
|
return -ENODEV;
|
|
|
|
}
|
|
|
|
return minor;
|
2014-08-15 10:54:11 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
gb_tty->minor = minor;
|
|
|
|
gb_tty->gdev = gdev;
|
|
|
|
spin_lock_init(&gb_tty->write_lock);
|
|
|
|
spin_lock_init(&gb_tty->read_lock);
|
2014-08-15 11:44:32 +00:00
|
|
|
init_waitqueue_head(&gb_tty->wioctl);
|
|
|
|
mutex_init(&gb_tty->mutex);
|
2014-08-15 10:54:11 +00:00
|
|
|
|
|
|
|
/* FIXME - allocate gb buffers */
|
|
|
|
|
2014-08-30 23:54:05 +00:00
|
|
|
gdev->gb_tty = gb_tty;
|
2014-08-15 10:54:11 +00:00
|
|
|
|
|
|
|
tty_dev = tty_port_register_device(&gb_tty->port, gb_tty_driver, minor,
|
|
|
|
&gdev->dev);
|
|
|
|
if (IS_ERR(tty_dev)) {
|
|
|
|
retval = PTR_ERR(tty_dev);
|
|
|
|
goto error;
|
|
|
|
}
|
2014-08-15 08:01:23 +00:00
|
|
|
|
|
|
|
return 0;
|
2014-08-15 10:54:11 +00:00
|
|
|
error:
|
2014-08-30 23:54:05 +00:00
|
|
|
gdev->gb_tty = NULL;
|
2014-08-15 10:54:11 +00:00
|
|
|
release_minor(gb_tty);
|
|
|
|
return retval;
|
2014-08-15 08:01:23 +00:00
|
|
|
}
|
|
|
|
|
2014-08-30 23:47:26 +00:00
|
|
|
void gb_tty_disconnect(struct greybus_device *gdev)
|
2014-08-15 08:01:23 +00:00
|
|
|
{
|
2014-08-30 23:54:05 +00:00
|
|
|
struct gb_tty *gb_tty = gdev->gb_tty;
|
2014-08-15 10:54:11 +00:00
|
|
|
struct tty_struct *tty;
|
|
|
|
|
2014-08-15 11:44:32 +00:00
|
|
|
if (!gb_tty)
|
|
|
|
return;
|
|
|
|
|
|
|
|
mutex_lock(&gb_tty->mutex);
|
|
|
|
gb_tty->disconnected = true;
|
|
|
|
|
|
|
|
wake_up_all(&gb_tty->wioctl);
|
2014-08-30 23:54:05 +00:00
|
|
|
gdev->gb_tty = NULL;
|
2014-08-15 11:44:32 +00:00
|
|
|
mutex_unlock(&gb_tty->mutex);
|
|
|
|
|
2014-08-15 10:54:11 +00:00
|
|
|
tty = tty_port_tty_get(&gb_tty->port);
|
|
|
|
if (tty) {
|
|
|
|
tty_vhangup(tty);
|
|
|
|
tty_kref_put(tty);
|
|
|
|
}
|
|
|
|
/* FIXME - stop all traffic */
|
|
|
|
|
|
|
|
tty_unregister_device(gb_tty_driver, gb_tty->minor);
|
|
|
|
|
2014-08-15 11:44:32 +00:00
|
|
|
/* FIXME - free transmit / recieve buffers */
|
|
|
|
|
2014-08-15 10:54:11 +00:00
|
|
|
tty_port_put(&gb_tty->port);
|
2014-08-31 00:11:41 +00:00
|
|
|
|
|
|
|
kfree(gb_tty);
|
2014-08-15 08:01:23 +00:00
|
|
|
}
|
|
|
|
|
2014-09-14 00:02:47 +00:00
|
|
|
#if 0
|
2014-08-15 08:01:23 +00:00
|
|
|
static struct greybus_driver tty_gb_driver = {
|
2014-08-30 23:47:26 +00:00
|
|
|
.probe = gb_tty_probe,
|
|
|
|
.disconnect = gb_tty_disconnect,
|
2014-08-15 08:01:23 +00:00
|
|
|
.id_table = id_table,
|
|
|
|
};
|
2014-09-14 00:02:47 +00:00
|
|
|
#endif
|
2014-08-15 08:01:23 +00:00
|
|
|
|
2014-08-30 23:47:26 +00:00
|
|
|
int __init gb_tty_init(void)
|
2014-08-15 08:01:23 +00:00
|
|
|
{
|
2014-09-06 03:56:10 +00:00
|
|
|
int retval = 0;
|
2014-08-15 08:01:23 +00:00
|
|
|
|
2014-09-06 03:56:09 +00:00
|
|
|
gb_tty_driver = tty_alloc_driver(GB_NUM_MINORS, 0);
|
2014-09-06 03:56:10 +00:00
|
|
|
if (IS_ERR(gb_tty_driver)) {
|
2014-09-13 23:15:52 +00:00
|
|
|
pr_err("Can not allocate tty driver\n");
|
2014-09-06 03:56:10 +00:00
|
|
|
retval = -ENOMEM;
|
|
|
|
goto fail_unregister_dev;
|
|
|
|
}
|
2014-08-15 08:01:23 +00:00
|
|
|
|
|
|
|
gb_tty_driver->driver_name = "gb";
|
2014-09-06 03:56:10 +00:00
|
|
|
gb_tty_driver->name = GB_NAME;
|
2014-09-13 23:15:52 +00:00
|
|
|
gb_tty_driver->major = 0;
|
|
|
|
gb_tty_driver->minor_start = 0;
|
2014-08-15 08:01:23 +00:00
|
|
|
gb_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
|
|
|
|
gb_tty_driver->subtype = SERIAL_TYPE_NORMAL;
|
|
|
|
gb_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
|
|
|
|
gb_tty_driver->init_termios = tty_std_termios;
|
|
|
|
gb_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
|
|
|
|
tty_set_operations(gb_tty_driver, &gb_ops);
|
|
|
|
|
|
|
|
retval = tty_register_driver(gb_tty_driver);
|
2014-09-13 23:15:52 +00:00
|
|
|
if (retval) {
|
|
|
|
pr_err("Can not register tty driver: %d\n", retval);
|
2014-09-06 03:56:10 +00:00
|
|
|
goto fail_put_gb_tty;
|
2014-09-13 23:15:52 +00:00
|
|
|
}
|
2014-08-15 08:01:23 +00:00
|
|
|
|
2014-09-13 23:15:52 +00:00
|
|
|
#if 0
|
2014-08-15 08:01:23 +00:00
|
|
|
retval = greybus_register(&tty_gb_driver);
|
2014-09-13 23:15:52 +00:00
|
|
|
if (retval) {
|
|
|
|
pr_err("Can not register greybus driver.\n");
|
2014-09-06 03:56:10 +00:00
|
|
|
goto fail_unregister_gb_tty;
|
2014-09-13 23:15:52 +00:00
|
|
|
}
|
|
|
|
#endif
|
2014-09-06 03:56:10 +00:00
|
|
|
|
|
|
|
return 0;
|
|
|
|
|
2014-09-14 00:02:47 +00:00
|
|
|
/* fail_unregister_gb_tty: */
|
2014-09-06 03:56:10 +00:00
|
|
|
tty_unregister_driver(gb_tty_driver);
|
2014-09-14 00:02:47 +00:00
|
|
|
fail_put_gb_tty:
|
2014-09-06 03:56:10 +00:00
|
|
|
put_tty_driver(gb_tty_driver);
|
2014-09-14 00:02:47 +00:00
|
|
|
fail_unregister_dev:
|
2014-08-15 08:01:23 +00:00
|
|
|
return retval;
|
|
|
|
}
|
|
|
|
|
2014-08-30 23:47:26 +00:00
|
|
|
void __exit gb_tty_exit(void)
|
2014-08-15 08:01:23 +00:00
|
|
|
{
|
2014-09-06 03:56:10 +00:00
|
|
|
int major = MAJOR(gb_tty_driver->major);
|
|
|
|
int minor = gb_tty_driver->minor_start;
|
2014-09-14 00:02:47 +00:00
|
|
|
|
|
|
|
#if 0
|
|
|
|
greybus_deregister(&tty_gb_driver);
|
|
|
|
#endif
|
2014-08-15 08:01:23 +00:00
|
|
|
tty_unregister_driver(gb_tty_driver);
|
|
|
|
put_tty_driver(gb_tty_driver);
|
2014-09-06 03:56:10 +00:00
|
|
|
unregister_chrdev_region(MKDEV(major, minor), GB_NUM_MINORS);
|
2014-08-15 08:01:23 +00:00
|
|
|
}
|
|
|
|
|
2014-08-30 23:47:26 +00:00
|
|
|
#if 0
|
2014-08-15 08:01:23 +00:00
|
|
|
module_init(gb_tty_init);
|
|
|
|
module_exit(gb_tty_exit);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
|
|
MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org>");
|
2014-08-30 23:47:26 +00:00
|
|
|
#endif
|