Re: [patch 0/7] staging: speakup: migrate synths to use TTY-based comms

[Okash Khawaja <okash.khawaja@gmail.com>]

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On Mon, Apr 03, 2017 at 09:21:23PM +0100, Okash Khawaja wrote:
> Hi,
> 
> This patchset migrates synths to use TTY-based comms instead of directly using
> serial i/o. The move doesn't cover those synths which do need direct access,
> e.g. some which talk over ISA.
> 
> Please note that this patchset applies on top of current staging-next branch of
> Greg Kroah-Hartman's tree as that contains some other changes to speakup and
> tty drivers that have recently gone in. So the first patch makes ammendments to
> TTY code which allows speakup to access and tty device. Next patch adds
> spk_ttyio.c which contains TTY-based initialisation and output functionality.
> Next patch migrates those synths which only use output: dummy, acntsa, bns and
> txprt. Then we add xchar and tiocmset functions. Next we rearrange the code
> such that input functionality is grouped under a few methods inside spk_synth
> and spk_io_ops structs. That paves the way for simple migration of other synths
> to TTY. The final patch does that for apollo, ltlk, audptr, decext, dectlk
> and spkout.
> 
> Thanks,
> Okash


Hi,

The staging-next tree wasn't working for me, specially the usb modules.
So I took following steps:

1. Switch to kernel versio 4.10.0 (I guess others upto 4.10.8 will be
fine)

2. Copy drivers/staging/speakup directory from staging-next tree to
overwrite the one in 4.10.0.

3. Use the patch I have attached as the first patch instead of the one
in this email series ([patch 1/7] staging: speakup: export
tty_open_by_driver).

4. Apply rest of the patches in this patchset.

That worked for me. As I have mentioned before, apollo and double talk
lt worked fine but I haven't done thorough testing. If you have
questions about applying patches, do let me know.

Thanks,
Okash

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^[[32mIndex: linux-stable/drivers/tty/tty_io.c^[[00m
===================================================================
^[[32m--- linux-stable.orig/drivers/tty/tty_io.c^[[00m
^[[32m+++ linux-stable/drivers/tty/tty_io.c^[[00m
^[[33m@@ -855,7 +855,7 @@^[[00m^[[35m^[[00m
 
 int tty_hung_up_p(struct file *filp)
 {
^[[35m-	return (filp->f_op == &hung_up_tty_fops);^[[00m
^[[36m+	return (filp && filp->f_op == &hung_up_tty_fops);^[[00m
 }
 
 EXPORT_SYMBOL(tty_hung_up_p);
^[[33m@@ -1368,7 +1368,10 @@^[[00m^[[35m^[[00m
 	struct tty_struct *tty;
 
 	if (driver->ops->lookup)
^[[35m-		tty = driver->ops->lookup(driver, file, idx);^[[00m
^[[36m+		if (!file)^[[00m
^[[36m+			tty = ERR_PTR(-EIO);^[[00m
^[[36m+		else^[[00m
^[[36m+			tty = driver->ops->lookup(driver, file, idx);^[[00m
 	else
 		tty = driver->ttys[idx];
 
^[[33m@@ -1986,7 +1989,7 @@^[[00m^[[35m^[[00m
 		struct tty_driver *console_driver = console_device(index);
 		if (console_driver) {
 			driver = tty_driver_kref_get(console_driver);
^[[35m-			if (driver) {^[[00m
^[[36m+			if (driver && filp) {^[[00m
 				/* Don't let /dev/console block */
 				filp->f_flags |= O_NONBLOCK;
 				break;
^[[33m@@ -2019,7 +2022,7 @@^[[00m^[[35m^[[00m
  *	  - concurrent tty driver removal w/ lookup
  *	  - concurrent tty removal from driver table
  */
^[[35m-static struct tty_struct *tty_open_by_driver(dev_t device, struct inode *inode,^[[00m
^[[36m+struct tty_struct *tty_open_by_driver(dev_t device, struct inode *inode,^[[00m
 					     struct file *filp)
 {
 	struct tty_struct *tty;
^[[33m@@ -2064,6 +2067,7 @@^[[00m^[[35m^[[00m
 	tty_driver_kref_put(driver);
 	return tty;
 }
^[[36m+EXPORT_SYMBOL(tty_open_by_driver);^[[00m
 
 /**
  *	tty_open		-	open a tty device
^[[32mIndex: linux-stable/drivers/tty/tty_port.c^[[00m
===================================================================
^[[32m--- linux-stable.orig/drivers/tty/tty_port.c^[[00m
^[[32m+++ linux-stable/drivers/tty/tty_port.c^[[00m
^[[33m@@ -335,7 +335,7 @@^[[00m^[[35m^[[00m
  *	tty_port_block_til_ready	-	Waiting logic for tty open
  *	@port: the tty port being opened
  *	@tty: the tty device being bound
^[[35m- *	@filp: the file pointer of the opener^[[00m
^[[36m+ *	@filp: the file pointer of the opener or NULL^[[00m
  *
  *	Implement the core POSIX/SuS tty behaviour when opening a tty device.
  *	Handles:
^[[33m@@ -369,7 +369,7 @@^[[00m^[[35m^[[00m
 		tty_port_set_active(port, 1);
 		return 0;
 	}
^[[35m-	if (filp->f_flags & O_NONBLOCK) {^[[00m
^[[36m+	if (filp ==  NULL || filp->f_flags & O_NONBLOCK) {^[[00m
 		/* Indicate we are open */
 		if (C_BAUD(tty))
 			tty_port_raise_dtr_rts(port);
^[[32mIndex: linux-stable/include/linux/tty.h^[[00m
===================================================================
^[[32m--- linux-stable.orig/include/linux/tty.h^[[00m
^[[32m+++ linux-stable/include/linux/tty.h^[[00m
^[[33m@@ -394,6 +394,8 @@^[[00m^[[35m^[[00m
 /* tty_io.c */
 extern int __init tty_init(void);
 extern const char *tty_name(const struct tty_struct *tty);
^[[36m+extern struct tty_struct *tty_open_by_driver(dev_t device, struct inode *inode,^[[00m
^[[36m+					     struct file *filp);^[[00m
 #else
 static inline void console_init(void)
 { }