[patch v4 0/3] staging: speakup: support more than ttyS*

[patch v4 0/3] staging: speakup: support more than ttyS*

[Okash Khawaja]

Hi,

v3 of this patch set introduced the compiler warning:

drivers//tty/tty_io.c:348:11: warning: assignment discards 'const'
qualifier from pointer target type [-Wdiscarded-qualifiers]

This version fixes that warning in patch 1/3.

Thanks,
Okash

[patch v4 1/3] tty: add function to convert device name to number

[Okash Khawaja]

[-- Attachment #1: 11_add_tty_dev_name_to_number --]
[-- Type: text/plain, Size: 2710 bytes --]

The function converts strings like ttyS0 and ttyUSB0 to dev_t like
(4, 64) and (188, 0). It does this by scanning tty_drivers list for
corresponding device name and index. If the driver is not registered,
this function returns -ENODEV. It also acquires tty_mutex.

Signed-off-by: Okash Khawaja <okash.khawaja@gmail.com>

---
 drivers/tty/tty_io.c |   50 ++++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/tty.h  |    3 +++
 2 files changed, 53 insertions(+)

--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -325,6 +325,56 @@ static struct tty_driver *get_tty_driver
 	return NULL;
 }
 
+/**
+ *	tty_dev_name_to_number	-	return dev_t for device name
+ *	@name: user space name of device under /dev
+ *	@number: pointer to dev_t that this function will populate
+ *
+ *	This function converts device names like ttyS0 or ttyUSB1 into dev_t
+ *	like (4, 64) or (188, 1). If no corresponding driver is registered then
+ *	the function returns -ENODEV.
+ *
+ *	Locking: this acquires tty_mutex to protect the tty_drivers list from
+ *		being modified while we are traversing it, and makes sure to
+ *		release it before exiting.
+ */
+int tty_dev_name_to_number(const char *name, dev_t *number)
+{
+	struct tty_driver *p;
+	int ret;
+	int index, prefix_length = 0;
+	const char *str;
+
+	for (str = name; *str && !isdigit(*str); str++)
+		;
+
+	if (!*str)
+		return -EINVAL;
+
+	ret = kstrtoint(str, 10, &index);
+	if (ret)
+		return ret;
+
+	prefix_length = str - name;
+	mutex_lock(&tty_mutex);
+
+	list_for_each_entry(p, &tty_drivers, tty_drivers)
+		if (prefix_length == strlen(p->name) && strncmp(name,
+					p->name, prefix_length) == 0) {
+			if (index < p->num) {
+				*number = MKDEV(p->major, p->minor_start + index);
+				goto out;
+			}
+		}
+
+	/* if here then driver wasn't found */
+	ret = -ENODEV;
+out:
+	mutex_unlock(&tty_mutex);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(tty_dev_name_to_number);
+
 #ifdef CONFIG_CONSOLE_POLL
 
 /**
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -401,6 +401,7 @@ extern int __init tty_init(void);
 extern const char *tty_name(const struct tty_struct *tty);
 extern struct tty_struct *tty_open_by_driver(dev_t device, struct inode *inode,
 		struct file *filp);
+extern int tty_dev_name_to_number(const char *name, dev_t *number);
 #else
 static inline void tty_kref_put(struct tty_struct *tty)
 { }
@@ -424,6 +425,8 @@ static inline const char *tty_name(const
 static inline struct tty_struct *tty_open_by_driver(dev_t device,
 		struct inode *inode, struct file *filp)
 { return NULL; }
+static inline int tty_dev_name_to_number(const char *name, dev_t *number)
+{ return -ENOTSUPP; }
 #endif
 
 extern struct ktermios tty_std_termios;

[patch v4 2/3] staging: speakup: check and convert dev name or ser to dev_t

[Okash Khawaja]

[-- Attachment #1: 12_check_and_convert_dev_or_ser_to_number --]
[-- Type: text/plain, Size: 3025 bytes --]

This patch adds functionality to validate and convert either a device
name or 'ser' memmber of synth into dev_t. Subsequent patch in this set
will call it to convert user-specified device into device number. For
device name, this patch does some basic sanity checks on the string
passed in. It currently supports ttyS*, ttyUSB* and, for selected
synths, lp*.

The patch also introduces a string member variable named 'dev_name' to
struct spk_synth. 'dev_name' represents the device name - ttyUSB0 etc -
which needs conversion to dev_t.

Signed-off-by: Okash Khawaja <okash.khawaja@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

---
 drivers/staging/speakup/spk_priv.h  |    2 +
 drivers/staging/speakup/spk_ttyio.c |   42 ++++++++++++++++++++++++++++++++++++
 drivers/staging/speakup/spk_types.h |    1 
 3 files changed, 45 insertions(+)

--- a/drivers/staging/speakup/spk_priv.h
+++ b/drivers/staging/speakup/spk_priv.h
@@ -40,6 +40,8 @@
 
 #define KT_SPKUP 15
 #define SPK_SYNTH_TIMEOUT 100000 /* in micro-seconds */
+#define SYNTH_DEFAULT_DEV "ttyS0"
+#define SYNTH_DEFAULT_SER 0
 
 const struct old_serial_port *spk_serial_init(int index);
 void spk_stop_serial_interrupt(void);
--- a/drivers/staging/speakup/spk_ttyio.c
+++ b/drivers/staging/speakup/spk_ttyio.c
@@ -7,6 +7,11 @@
 #include "spk_types.h"
 #include "spk_priv.h"
 
+#define DEV_PREFIX_LP "lp"
+
+static const char * const lp_supported[] = { "acntsa", "bns", "dummy",
+	"txprt" };
+
 struct spk_ldisc_data {
 	char buf;
 	struct semaphore sem;
@@ -16,6 +21,43 @@ struct spk_ldisc_data {
 static struct spk_synth *spk_ttyio_synth;
 static struct tty_struct *speakup_tty;
 
+int ser_to_dev(int ser, dev_t *dev_no)
+{
+	if (ser < 0 || ser > (255 - 64)) {
+		pr_err("speakup: Invalid ser param. Must be between 0 and 191 inclusive.\n");
+		return -EINVAL;
+	}
+
+	*dev_no = MKDEV(4, (64 + ser));
+	return 0;
+}
+
+static int get_dev_to_use(struct spk_synth *synth, dev_t *dev_no)
+{
+	/* use ser only when dev is not specified */
+	if (strcmp(synth->dev_name, SYNTH_DEFAULT_DEV) ||
+	    synth->ser == SYNTH_DEFAULT_SER) {
+		/* for /dev/lp* check if synth is supported */
+		if (strncmp(synth->dev_name, DEV_PREFIX_LP,
+		    strlen(DEV_PREFIX_LP)) == 0)
+			if (match_string(lp_supported, ARRAY_SIZE(lp_supported),
+			    synth->name) < 0)  {
+				int i;
+
+				pr_err("speakup: lp* is only supported on:");
+				for (i = 0; i < ARRAY_SIZE(lp_supported); i++)
+					pr_cont(" %s", lp_supported[i]);
+				pr_cont("\n");
+
+				return -ENOTSUPP;
+			}
+
+		return tty_dev_name_to_number(synth->dev_name, dev_no);
+	}
+
+	return ser_to_dev(synth->ser, dev_no);
+}
+
 static int spk_ttyio_ldisc_open(struct tty_struct *tty)
 {
 	struct spk_ldisc_data *ldisc_data;
--- a/drivers/staging/speakup/spk_types.h
+++ b/drivers/staging/speakup/spk_types.h
@@ -169,6 +169,7 @@ struct spk_synth {
 	int jiffies;
 	int full;
 	int ser;
+	char *dev_name;
 	short flags;
 	short startup;
 	const int checkval; /* for validating a proper synth module */

[patch v4 3/3] staging: speakup: make ttyio synths use device name

[Okash Khawaja]

[-- Attachment #1: 13_make_ttyio_use_device_name --]
[-- Type: text/plain, Size: 10793 bytes --]

This patch introduces new module parameter, dev, which takes a string
representing the device that the external synth is connected to, e.g.
ttyS0, ttyUSB0 etc. This is then used to communicate with the synth.
That way, speakup can support more than ttyS*. As of this patch, it
only supports ttyS*, ttyUSB* and selected synths for lp*. dev parameter
is only available for tty-migrated synths.

Users will either use dev or ser as both serve same purpose. This patch
maintains backward compatility by allowing ser to be specified. When
both are specified, whichever is non-default, i.e. not ttyS0, is used.
If both are non-default then dev is used.

Signed-off-by: Okash Khawaja <okash.khawaja@gmail.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

---
 drivers/staging/speakup/speakup_acntsa.c |    3 +++
 drivers/staging/speakup/speakup_apollo.c |    3 +++
 drivers/staging/speakup/speakup_audptr.c |    3 +++
 drivers/staging/speakup/speakup_bns.c    |    3 +++
 drivers/staging/speakup/speakup_decext.c |    3 +++
 drivers/staging/speakup/speakup_dectlk.c |    3 +++
 drivers/staging/speakup/speakup_dummy.c  |    3 +++
 drivers/staging/speakup/speakup_ltlk.c   |    3 +++
 drivers/staging/speakup/speakup_spkout.c |    3 +++
 drivers/staging/speakup/speakup_txprt.c  |    3 +++
 drivers/staging/speakup/spk_ttyio.c      |   15 +++++++--------
 11 files changed, 37 insertions(+), 8 deletions(-)

--- a/drivers/staging/speakup/speakup_acntsa.c
+++ b/drivers/staging/speakup/speakup_acntsa.c
@@ -96,6 +96,7 @@ static struct spk_synth synth_acntsa = {
 	.trigger = 50,
 	.jiffies = 30,
 	.full = 40000,
+	.dev_name = SYNTH_DEFAULT_DEV,
 	.startup = SYNTH_START,
 	.checkval = SYNTH_CHECK,
 	.vars = vars,
@@ -135,9 +136,11 @@ static int synth_probe(struct spk_synth
 }
 
 module_param_named(ser, synth_acntsa.ser, int, 0444);
+module_param_named(dev, synth_acntsa.dev_name, charp, S_IRUGO);
 module_param_named(start, synth_acntsa.startup, short, 0444);
 
 MODULE_PARM_DESC(ser, "Set the serial port for the synthesizer (0-based).");
+MODULE_PARM_DESC(dev, "Set the device e.g. ttyUSB0, for the synthesizer.");
 MODULE_PARM_DESC(start, "Start the synthesizer once it is loaded.");
 
 module_spk_synth(synth_acntsa);
--- a/drivers/staging/speakup/speakup_apollo.c
+++ b/drivers/staging/speakup/speakup_apollo.c
@@ -105,6 +105,7 @@ static struct spk_synth synth_apollo = {
 	.trigger = 50,
 	.jiffies = 50,
 	.full = 40000,
+	.dev_name = SYNTH_DEFAULT_DEV,
 	.startup = SYNTH_START,
 	.checkval = SYNTH_CHECK,
 	.vars = vars,
@@ -199,9 +200,11 @@ static void do_catch_up(struct spk_synth
 }
 
 module_param_named(ser, synth_apollo.ser, int, 0444);
+module_param_named(dev, synth_apollo.dev_name, charp, S_IRUGO);
 module_param_named(start, synth_apollo.startup, short, 0444);
 
 MODULE_PARM_DESC(ser, "Set the serial port for the synthesizer (0-based).");
+MODULE_PARM_DESC(dev, "Set the device e.g. ttyUSB0, for the synthesizer.");
 MODULE_PARM_DESC(start, "Start the synthesizer once it is loaded.");
 
 module_spk_synth(synth_apollo);
--- a/drivers/staging/speakup/speakup_audptr.c
+++ b/drivers/staging/speakup/speakup_audptr.c
@@ -100,6 +100,7 @@ static struct spk_synth synth_audptr = {
 	.trigger = 50,
 	.jiffies = 30,
 	.full = 18000,
+	.dev_name = SYNTH_DEFAULT_DEV,
 	.startup = SYNTH_START,
 	.checkval = SYNTH_CHECK,
 	.vars = vars,
@@ -162,9 +163,11 @@ static int synth_probe(struct spk_synth
 }
 
 module_param_named(ser, synth_audptr.ser, int, 0444);
+module_param_named(dev, synth_audptr.dev_name, charp, S_IRUGO);
 module_param_named(start, synth_audptr.startup, short, 0444);
 
 MODULE_PARM_DESC(ser, "Set the serial port for the synthesizer (0-based).");
+MODULE_PARM_DESC(dev, "Set the device e.g. ttyUSB0, for the synthesizer.");
 MODULE_PARM_DESC(start, "Start the synthesizer once it is loaded.");
 
 module_spk_synth(synth_audptr);
--- a/drivers/staging/speakup/speakup_bns.c
+++ b/drivers/staging/speakup/speakup_bns.c
@@ -93,6 +93,7 @@ static struct spk_synth synth_bns = {
 	.trigger = 50,
 	.jiffies = 50,
 	.full = 40000,
+	.dev_name = SYNTH_DEFAULT_DEV,
 	.startup = SYNTH_START,
 	.checkval = SYNTH_CHECK,
 	.vars = vars,
@@ -119,9 +120,11 @@ static struct spk_synth synth_bns = {
 };
 
 module_param_named(ser, synth_bns.ser, int, 0444);
+module_param_named(dev, synth_bns.dev_name, charp, S_IRUGO);
 module_param_named(start, synth_bns.startup, short, 0444);
 
 MODULE_PARM_DESC(ser, "Set the serial port for the synthesizer (0-based).");
+MODULE_PARM_DESC(dev, "Set the device e.g. ttyUSB0, for the synthesizer.");
 MODULE_PARM_DESC(start, "Start the synthesizer once it is loaded.");
 
 module_spk_synth(synth_bns);
--- a/drivers/staging/speakup/speakup_decext.c
+++ b/drivers/staging/speakup/speakup_decext.c
@@ -120,6 +120,7 @@ static struct spk_synth synth_decext = {
 	.jiffies = 50,
 	.full = 40000,
 	.flags = SF_DEC,
+	.dev_name = SYNTH_DEFAULT_DEV,
 	.startup = SYNTH_START,
 	.checkval = SYNTH_CHECK,
 	.vars = vars,
@@ -226,9 +227,11 @@ static void synth_flush(struct spk_synth
 }
 
 module_param_named(ser, synth_decext.ser, int, 0444);
+module_param_named(dev, synth_decext.dev_name, charp, S_IRUGO);
 module_param_named(start, synth_decext.startup, short, 0444);
 
 MODULE_PARM_DESC(ser, "Set the serial port for the synthesizer (0-based).");
+MODULE_PARM_DESC(dev, "Set the device e.g. ttyUSB0, for the synthesizer.");
 MODULE_PARM_DESC(start, "Start the synthesizer once it is loaded.");
 
 module_spk_synth(synth_decext);
--- a/drivers/staging/speakup/speakup_dectlk.c
+++ b/drivers/staging/speakup/speakup_dectlk.c
@@ -124,6 +124,7 @@ static struct spk_synth synth_dectlk = {
 	.trigger = 50,
 	.jiffies = 50,
 	.full = 40000,
+	.dev_name = SYNTH_DEFAULT_DEV,
 	.startup = SYNTH_START,
 	.checkval = SYNTH_CHECK,
 	.vars = vars,
@@ -298,9 +299,11 @@ static void synth_flush(struct spk_synth
 }
 
 module_param_named(ser, synth_dectlk.ser, int, 0444);
+module_param_named(dev, synth_dectlk.dev_name, charp, S_IRUGO);
 module_param_named(start, synth_dectlk.startup, short, 0444);
 
 MODULE_PARM_DESC(ser, "Set the serial port for the synthesizer (0-based).");
+MODULE_PARM_DESC(dev, "Set the device e.g. ttyUSB0, for the synthesizer.");
 MODULE_PARM_DESC(start, "Start the synthesizer once it is loaded.");
 
 module_spk_synth(synth_dectlk);
--- a/drivers/staging/speakup/speakup_dummy.c
+++ b/drivers/staging/speakup/speakup_dummy.c
@@ -95,6 +95,7 @@ static struct spk_synth synth_dummy = {
 	.trigger = 50,
 	.jiffies = 50,
 	.full = 40000,
+	.dev_name = SYNTH_DEFAULT_DEV,
 	.startup = SYNTH_START,
 	.checkval = SYNTH_CHECK,
 	.vars = vars,
@@ -121,9 +122,11 @@ static struct spk_synth synth_dummy = {
 };
 
 module_param_named(ser, synth_dummy.ser, int, 0444);
+module_param_named(dev, synth_dummy.dev_name, charp, S_IRUGO);
 module_param_named(start, synth_dummy.startup, short, 0444);
 
 MODULE_PARM_DESC(ser, "Set the serial port for the synthesizer (0-based).");
+MODULE_PARM_DESC(dev, "Set the device e.g. ttyUSB0, for the synthesizer.");
 MODULE_PARM_DESC(start, "Start the synthesizer once it is loaded.");
 
 module_spk_synth(synth_dummy);
--- a/drivers/staging/speakup/speakup_ltlk.c
+++ b/drivers/staging/speakup/speakup_ltlk.c
@@ -107,6 +107,7 @@ static struct spk_synth synth_ltlk = {
 	.trigger = 50,
 	.jiffies = 50,
 	.full = 40000,
+	.dev_name = SYNTH_DEFAULT_DEV,
 	.startup = SYNTH_START,
 	.checkval = SYNTH_CHECK,
 	.vars = vars,
@@ -166,9 +167,11 @@ static int synth_probe(struct spk_synth
 }
 
 module_param_named(ser, synth_ltlk.ser, int, 0444);
+module_param_named(dev, synth_ltlk.dev_name, charp, S_IRUGO);
 module_param_named(start, synth_ltlk.startup, short, 0444);
 
 MODULE_PARM_DESC(ser, "Set the serial port for the synthesizer (0-based).");
+MODULE_PARM_DESC(dev, "Set the device e.g. ttyUSB0, for the synthesizer.");
 MODULE_PARM_DESC(start, "Start the synthesizer once it is loaded.");
 
 module_spk_synth(synth_ltlk);
--- a/drivers/staging/speakup/speakup_spkout.c
+++ b/drivers/staging/speakup/speakup_spkout.c
@@ -98,6 +98,7 @@ static struct spk_synth synth_spkout = {
 	.trigger = 50,
 	.jiffies = 50,
 	.full = 40000,
+	.dev_name = SYNTH_DEFAULT_DEV,
 	.startup = SYNTH_START,
 	.checkval = SYNTH_CHECK,
 	.vars = vars,
@@ -130,9 +131,11 @@ static void synth_flush(struct spk_synth
 }
 
 module_param_named(ser, synth_spkout.ser, int, 0444);
+module_param_named(dev, synth_spkout.dev_name, charp, S_IRUGO);
 module_param_named(start, synth_spkout.startup, short, 0444);
 
 MODULE_PARM_DESC(ser, "Set the serial port for the synthesizer (0-based).");
+MODULE_PARM_DESC(dev, "Set the device e.g. ttyUSB0, for the synthesizer.");
 MODULE_PARM_DESC(start, "Start the synthesizer once it is loaded.");
 
 module_spk_synth(synth_spkout);
--- a/drivers/staging/speakup/speakup_txprt.c
+++ b/drivers/staging/speakup/speakup_txprt.c
@@ -92,6 +92,7 @@ static struct spk_synth synth_txprt = {
 	.trigger = 50,
 	.jiffies = 50,
 	.full = 40000,
+	.dev_name = SYNTH_DEFAULT_DEV,
 	.startup = SYNTH_START,
 	.checkval = SYNTH_CHECK,
 	.vars = vars,
@@ -118,9 +119,11 @@ static struct spk_synth synth_txprt = {
 };
 
 module_param_named(ser, synth_txprt.ser, int, 0444);
+module_param_named(dev, synth_txprt.dev_name, charp, S_IRUGO);
 module_param_named(start, synth_txprt.startup, short, 0444);
 
 MODULE_PARM_DESC(ser, "Set the serial port for the synthesizer (0-based).");
+MODULE_PARM_DESC(dev, "Set the device e.g. ttyUSB0, for the synthesizer.");
 MODULE_PARM_DESC(start, "Start the synthesizer once it is loaded.");
 
 module_spk_synth(synth_txprt);
--- a/drivers/staging/speakup/spk_ttyio.c
+++ b/drivers/staging/speakup/spk_ttyio.c
@@ -147,11 +147,12 @@ static inline void get_termios(struct tt
 	up_read(&tty->termios_rwsem);
 }
 
-static int spk_ttyio_initialise_ldisc(int ser)
+static int spk_ttyio_initialise_ldisc(struct spk_synth *synth)
 {
 	int ret = 0;
 	struct tty_struct *tty;
 	struct ktermios tmp_termios;
+	dev_t dev;
 
 	ret = tty_register_ldisc(N_SPEAKUP, &spk_ttyio_ldisc_ops);
 	if (ret) {
@@ -159,13 +160,11 @@ static int spk_ttyio_initialise_ldisc(in
 		return ret;
 	}
 
-	if (ser < 0 || ser > (255 - 64)) {
-		pr_err("speakup: Invalid ser param. Must be between 0 and 191 inclusive.\n");
-		return -EINVAL;
-	}
+	ret = get_dev_to_use(synth, &dev);
+	if (ret)
+		return ret;
 
-	/* TODO: support more than ttyS* */
-	tty = tty_open_by_driver(MKDEV(4, (ser +  64)), NULL, NULL);
+	tty = tty_open_by_driver(dev, NULL, NULL);
 	if (IS_ERR(tty))
 		return PTR_ERR(tty);
 
@@ -277,7 +276,7 @@ static void spk_ttyio_flush_buffer(void)
 
 int spk_ttyio_synth_probe(struct spk_synth *synth)
 {
-	int rv = spk_ttyio_initialise_ldisc(synth->ser);
+	int rv = spk_ttyio_initialise_ldisc(synth);
 
 	if (rv)
 		return rv;