From 7a786b84790789eff5bad49e3f6c15f75b7bf691 Mon Sep 17 00:00:00 2001 From: Matthew Michilot Date: Thu, 15 Aug 2019 17:40:54 +0000 Subject: USB: serial: ftdi_sio: add support for FT232H CBUS gpios Enable support for cbus gpios on FT232H. The cbus configuration is stored in two words in the EEPROM at byte-offset 0x1a with the mux config for ACBUS5, ACBUS6, ACBUS8 and ACBUS9 (only pins that can be configured as I/O mode). Tested using FT232H by configuring one ACBUS pin at a time. Reviewed-by: Tim Harvey Signed-off-by: Matthew Michilot [ johan: fix copy-paste error in commit message ] Signed-off-by: Johan Hovold --- drivers/usb/serial/ftdi_sio.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) (limited to 'drivers/usb') diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c index 4b3a049561f3..f0688c44b04c 100644 --- a/drivers/usb/serial/ftdi_sio.c +++ b/drivers/usb/serial/ftdi_sio.c @@ -2023,6 +2023,46 @@ static int ftdi_read_eeprom(struct usb_serial *serial, void *dst, u16 addr, return 0; } +static int ftdi_gpio_init_ft232h(struct usb_serial_port *port) +{ + struct ftdi_private *priv = usb_get_serial_port_data(port); + u16 cbus_config; + u8 *buf; + int ret; + int i; + + buf = kmalloc(4, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + ret = ftdi_read_eeprom(port->serial, buf, 0x1a, 4); + if (ret < 0) + goto out_free; + + /* + * FT232H CBUS Memory Map + * + * 0x1a: X- (upper nibble -> AC5) + * 0x1b: -X (lower nibble -> AC6) + * 0x1c: XX (upper nibble -> AC9 | lower nibble -> AC8) + */ + cbus_config = buf[2] << 8 | (buf[1] & 0xf) << 4 | (buf[0] & 0xf0) >> 4; + + priv->gc.ngpio = 4; + priv->gpio_altfunc = 0xff; + + for (i = 0; i < priv->gc.ngpio; ++i) { + if ((cbus_config & 0xf) == FTDI_FTX_CBUS_MUX_GPIO) + priv->gpio_altfunc &= ~BIT(i); + cbus_config >>= 4; + } + +out_free: + kfree(buf); + + return ret; +} + static int ftdi_gpio_init_ft232r(struct usb_serial_port *port) { struct ftdi_private *priv = usb_get_serial_port_data(port); @@ -2098,6 +2138,9 @@ static int ftdi_gpio_init(struct usb_serial_port *port) int result; switch (priv->chip_type) { + case FT232H: + result = ftdi_gpio_init_ft232h(port); + break; case FT232RL: result = ftdi_gpio_init_ft232r(port); break; -- cgit v1.2.3