staging: speakup: check and convert dev name or ser to dev_t
authorOkash Khawaja <okash.khawaja@gmail.com>
Sun, 25 Jun 2017 18:40:01 +0000 (19:40 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 27 Jun 2017 07:12:33 +0000 (09:12 +0200)
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/staging/speakup/spk_priv.h
drivers/staging/speakup/spk_ttyio.c
drivers/staging/speakup/spk_types.h

index 4f533667d3125ff4a8cf52d23491ed0f96a96a97..87b6a0a4c54dc80c8cbbbbf3b3c7d4208827cbcc 100644 (file)
@@ -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);
index 4e346697e53d7f568afe115bd4187f55cb036278..0a5436706e74c2ecf7402f52556c28b6fbaa7e2a 100644 (file)
@@ -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;
index 9e3889749d4315c6991926b74a1e0e5a7d004a34..22f657d45e46da041b13619192a307c9ccb96494 100644 (file)
@@ -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 */