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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-02-10 11:12:55 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-02-10 11:13:53 -0800
commit7483948fdd31a8642ef0288aab6f368b98d53c29 (patch)
tree031020a5553701d2aae8dddb0fa509aa65854eb1 /drivers/usb/serial/cp210x.c
parent22a416c4e0f2179b57028e084ac0ed2c110333bd (diff)
parentfe250923bbbbcbccc9aa7b84d05ee7a060450534 (diff)
downloadlinux-stericsson-7483948fdd31a8642ef0288aab6f368b98d53c29.tar.gz
Merge tag 'usb-3.3-rc3' into usb-next
This is done to resolve a merge conflict with: drivers/usb/class/cdc-wdm.c and to better handle future patches for this driver as it is under active development at the moment. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/serial/cp210x.c')
-rw-r--r--drivers/usb/serial/cp210x.c105
1 files changed, 75 insertions, 30 deletions
diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c
index 92aadd889a6d..90721b49eed7 100644
--- a/drivers/usb/serial/cp210x.c
+++ b/drivers/usb/serial/cp210x.c
@@ -39,6 +39,8 @@ static void cp210x_get_termios(struct tty_struct *,
struct usb_serial_port *port);
static void cp210x_get_termios_port(struct usb_serial_port *port,
unsigned int *cflagp, unsigned int *baudp);
+static void cp210x_change_speed(struct tty_struct *, struct usb_serial_port *,
+ struct ktermios *);
static void cp210x_set_termios(struct tty_struct *, struct usb_serial_port *,
struct ktermios*);
static int cp210x_tiocmget(struct tty_struct *);
@@ -138,6 +140,7 @@ static const struct usb_device_id id_table[] = {
{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
+ { USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
{ } /* Terminating Entry */
};
@@ -201,6 +204,8 @@ static struct usb_serial_driver cp210x_device = {
#define CP210X_EMBED_EVENTS 0x15
#define CP210X_GET_EVENTSTATE 0x16
#define CP210X_SET_CHARS 0x19
+#define CP210X_GET_BAUDRATE 0x1D
+#define CP210X_SET_BAUDRATE 0x1E
/* CP210X_IFC_ENABLE */
#define UART_ENABLE 0x0001
@@ -360,8 +365,8 @@ static inline int cp210x_set_config_single(struct usb_serial_port *port,
* Quantises the baud rate as per AN205 Table 1
*/
static unsigned int cp210x_quantise_baudrate(unsigned int baud) {
- if (baud <= 56) baud = 0;
- else if (baud <= 300) baud = 300;
+ if (baud <= 300)
+ baud = 300;
else if (baud <= 600) baud = 600;
else if (baud <= 1200) baud = 1200;
else if (baud <= 1800) baud = 1800;
@@ -389,10 +394,10 @@ static unsigned int cp210x_quantise_baudrate(unsigned int baud) {
else if (baud <= 491520) baud = 460800;
else if (baud <= 567138) baud = 500000;
else if (baud <= 670254) baud = 576000;
- else if (baud <= 1053257) baud = 921600;
- else if (baud <= 1474560) baud = 1228800;
- else if (baud <= 2457600) baud = 1843200;
- else baud = 3686400;
+ else if (baud < 1000000)
+ baud = 921600;
+ else if (baud > 2000000)
+ baud = 2000000;
return baud;
}
@@ -409,13 +414,14 @@ static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
return result;
}
- result = usb_serial_generic_open(tty, port);
- if (result)
- return result;
-
/* Configure the termios structure */
cp210x_get_termios(tty, port);
- return 0;
+
+ /* The baud rate must be initialised on cp2104 */
+ if (tty)
+ cp210x_change_speed(tty, port, NULL);
+
+ return usb_serial_generic_open(tty, port);
}
static void cp210x_close(struct usb_serial_port *port)
@@ -467,10 +473,7 @@ static void cp210x_get_termios_port(struct usb_serial_port *port,
dbg("%s - port %d", __func__, port->number);
- cp210x_get_config(port, CP210X_GET_BAUDDIV, &baud, 2);
- /* Convert to baudrate */
- if (baud)
- baud = cp210x_quantise_baudrate((BAUD_RATE_GEN_FREQ + baud/2)/ baud);
+ cp210x_get_config(port, CP210X_GET_BAUDRATE, &baud, 4);
dbg("%s - baud rate = %d", __func__, baud);
*baudp = baud;
@@ -579,11 +582,64 @@ static void cp210x_get_termios_port(struct usb_serial_port *port,
*cflagp = cflag;
}
+/*
+ * CP2101 supports the following baud rates:
+ *
+ * 300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
+ * 38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
+ *
+ * CP2102 and CP2103 support the following additional rates:
+ *
+ * 4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
+ * 576000
+ *
+ * The device will map a requested rate to a supported one, but the result
+ * of requests for rates greater than 1053257 is undefined (see AN205).
+ *
+ * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
+ * respectively, with an error less than 1%. The actual rates are determined
+ * by
+ *
+ * div = round(freq / (2 x prescale x request))
+ * actual = freq / (2 x prescale x div)
+ *
+ * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
+ * or 1 otherwise.
+ * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
+ * otherwise.
+ */
+static void cp210x_change_speed(struct tty_struct *tty,
+ struct usb_serial_port *port, struct ktermios *old_termios)
+{
+ u32 baud;
+
+ baud = tty->termios->c_ospeed;
+
+ /* This maps the requested rate to a rate valid on cp2102 or cp2103,
+ * or to an arbitrary rate in [1M,2M].
+ *
+ * NOTE: B0 is not implemented.
+ */
+ baud = cp210x_quantise_baudrate(baud);
+
+ dbg("%s - setting baud rate to %u", __func__, baud);
+ if (cp210x_set_config(port, CP210X_SET_BAUDRATE, &baud,
+ sizeof(baud))) {
+ dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
+ if (old_termios)
+ baud = old_termios->c_ospeed;
+ else
+ baud = 9600;
+ }
+
+ tty_encode_baud_rate(tty, baud, baud);
+}
+
static void cp210x_set_termios(struct tty_struct *tty,
struct usb_serial_port *port, struct ktermios *old_termios)
{
unsigned int cflag, old_cflag;
- unsigned int baud = 0, bits;
+ unsigned int bits;
unsigned int modem_ctl[4];
dbg("%s - port %d", __func__, port->number);
@@ -593,20 +649,9 @@ static void cp210x_set_termios(struct tty_struct *tty,
cflag = tty->termios->c_cflag;
old_cflag = old_termios->c_cflag;
- baud = cp210x_quantise_baudrate(tty_get_baud_rate(tty));
-
- /* If the baud rate is to be updated*/
- if (baud != tty_termios_baud_rate(old_termios) && baud != 0) {
- dbg("%s - Setting baud rate to %d baud", __func__,
- baud);
- if (cp210x_set_config_single(port, CP210X_SET_BAUDDIV,
- ((BAUD_RATE_GEN_FREQ + baud/2) / baud))) {
- dbg("Baud rate requested not supported by device");
- baud = tty_termios_baud_rate(old_termios);
- }
- }
- /* Report back the resulting baud rate */
- tty_encode_baud_rate(tty, baud, baud);
+
+ if (tty->termios->c_ospeed != old_termios->c_ospeed)
+ cp210x_change_speed(tty, port, old_termios);
/* If the number of data bits is to be updated */
if ((cflag & CSIZE) != (old_cflag & CSIZE)) {