From 268ddb5e9b62221beda22b8e956cf6e732538a90 Mon Sep 17 00:00:00 2001 From: "Ji-Ze Hong (Peter Hong)" Date: Tue, 30 Apr 2019 09:22:31 +0800 Subject: USB: serial: f81232: add high baud rate support The F81232 had 4 clocksource 1.846/18.46/14.77/24MHz and baud rates can be up to 1.5Mbits with 24MHz. F81232 Clock registers (106h) Bit1-0: Clock source selector 00: 1.846MHz. 01: 18.46MHz. 10: 24MHz. 11: 14.77MHz. Signed-off-by: Ji-Ze Hong (Peter Hong) Signed-off-by: Johan Hovold --- drivers/usb/serial/f81232.c | 105 +++++++++++++++++++++++++++++++++++++++----- 1 file changed, 94 insertions(+), 11 deletions(-) (limited to 'drivers/usb') diff --git a/drivers/usb/serial/f81232.c b/drivers/usb/serial/f81232.c index 840694bf57c1..4f65ddd65cab 100644 --- a/drivers/usb/serial/f81232.c +++ b/drivers/usb/serial/f81232.c @@ -28,7 +28,8 @@ static const struct usb_device_id id_table[] = { MODULE_DEVICE_TABLE(usb, id_table); /* Maximum baudrate for F81232 */ -#define F81232_MAX_BAUDRATE 115200 +#define F81232_MAX_BAUDRATE 1500000 +#define F81232_DEF_BAUDRATE 9600 /* USB Control EP parameter */ #define F81232_REGISTER_REQUEST 0xa0 @@ -44,18 +45,42 @@ MODULE_DEVICE_TABLE(usb, id_table); #define LINE_STATUS_REGISTER (0x05 + SERIAL_BASE_ADDRESS) #define MODEM_STATUS_REGISTER (0x06 + SERIAL_BASE_ADDRESS) +/* + * F81232 Clock registers (106h) + * + * Bit1-0: Clock source selector + * 00: 1.846MHz. + * 01: 18.46MHz. + * 10: 24MHz. + * 11: 14.77MHz. + */ +#define F81232_CLK_REGISTER 0x106 +#define F81232_CLK_1_846_MHZ 0 +#define F81232_CLK_18_46_MHZ BIT(0) +#define F81232_CLK_24_MHZ BIT(1) +#define F81232_CLK_14_77_MHZ (BIT(1) | BIT(0)) +#define F81232_CLK_MASK GENMASK(1, 0) + struct f81232_private { struct mutex lock; u8 modem_control; u8 modem_status; + speed_t baud_base; struct work_struct lsr_work; struct work_struct interrupt_work; struct usb_serial_port *port; }; -static int calc_baud_divisor(speed_t baudrate) +static u32 const baudrate_table[] = { 115200, 921600, 1152000, 1500000 }; +static u8 const clock_table[] = { F81232_CLK_1_846_MHZ, F81232_CLK_14_77_MHZ, + F81232_CLK_18_46_MHZ, F81232_CLK_24_MHZ }; + +static int calc_baud_divisor(speed_t baudrate, speed_t clockrate) { - return DIV_ROUND_CLOSEST(F81232_MAX_BAUDRATE, baudrate); + if (!baudrate) + return 0; + + return DIV_ROUND_CLOSEST(clockrate, baudrate); } static int f81232_get_register(struct usb_serial_port *port, u16 reg, u8 *val) @@ -129,6 +154,21 @@ static int f81232_set_register(struct usb_serial_port *port, u16 reg, u8 val) return status; } +static int f81232_set_mask_register(struct usb_serial_port *port, u16 reg, + u8 mask, u8 val) +{ + int status; + u8 tmp; + + status = f81232_get_register(port, reg, &tmp); + if (status) + return status; + + tmp = (tmp & ~mask) | (val & mask); + + return f81232_set_register(port, reg, tmp); +} + static void f81232_read_msr(struct usb_serial_port *port) { int status; @@ -346,13 +386,53 @@ static void f81232_break_ctl(struct tty_struct *tty, int break_state) */ } -static void f81232_set_baudrate(struct usb_serial_port *port, speed_t baudrate) +static int f81232_find_clk(speed_t baudrate) +{ + int idx; + + for (idx = 0; idx < ARRAY_SIZE(baudrate_table); ++idx) { + if (baudrate <= baudrate_table[idx] && + baudrate_table[idx] % baudrate == 0) + return idx; + } + + return -EINVAL; +} + +static void f81232_set_baudrate(struct tty_struct *tty, + struct usb_serial_port *port, speed_t baudrate, + speed_t old_baudrate) { + struct f81232_private *priv = usb_get_serial_port_data(port); u8 lcr; int divisor; int status = 0; + int i; + int idx; + speed_t baud_list[] = { baudrate, old_baudrate, F81232_DEF_BAUDRATE }; + + for (i = 0; i < ARRAY_SIZE(baud_list); ++i) { + idx = f81232_find_clk(baud_list[i]); + if (idx >= 0) { + baudrate = baud_list[i]; + tty_encode_baud_rate(tty, baudrate, baudrate); + break; + } + } + + if (idx < 0) + return; - divisor = calc_baud_divisor(baudrate); + priv->baud_base = baudrate_table[idx]; + divisor = calc_baud_divisor(baudrate, priv->baud_base); + + status = f81232_set_mask_register(port, F81232_CLK_REGISTER, + F81232_CLK_MASK, clock_table[idx]); + if (status) { + dev_err(&port->dev, "%s failed to set CLK_REG: %d\n", + __func__, status); + return; + } status = f81232_get_register(port, LINE_CONTROL_REGISTER, &lcr); /* get LCR */ @@ -442,6 +522,7 @@ static void f81232_set_termios(struct tty_struct *tty, u8 new_lcr = 0; int status = 0; speed_t baudrate; + speed_t old_baud; /* Don't change anything if nothing has changed */ if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios)) @@ -454,11 +535,12 @@ static void f81232_set_termios(struct tty_struct *tty, baudrate = tty_get_baud_rate(tty); if (baudrate > 0) { - if (baudrate > F81232_MAX_BAUDRATE) { - baudrate = F81232_MAX_BAUDRATE; - tty_encode_baud_rate(tty, baudrate, baudrate); - } - f81232_set_baudrate(port, baudrate); + if (old_termios) + old_baud = tty_termios_baud_rate(old_termios); + else + old_baud = F81232_DEF_BAUDRATE; + + f81232_set_baudrate(tty, port, baudrate, old_baud); } if (C_PARENB(tty)) { @@ -595,11 +677,12 @@ static int f81232_get_serial_info(struct tty_struct *tty, struct serial_struct *ss) { struct usb_serial_port *port = tty->driver_data; + struct f81232_private *priv = usb_get_serial_port_data(port); ss->type = PORT_16550A; ss->line = port->minor; ss->port = port->port_number; - ss->baud_base = F81232_MAX_BAUDRATE; + ss->baud_base = priv->baud_base; return 0; } -- cgit v1.2.3-59-g8ed1b