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authorMatthew Michilot <matthew.michilot@gmail.com>2019-08-15 17:40:54 +0000
committerJohan Hovold <johan@kernel.org>2019-08-28 15:35:33 +0200
commit7a786b84790789eff5bad49e3f6c15f75b7bf691 (patch)
tree91922a7b2bd7fa6a1d54004ee6c27a4580a691be /drivers/usb/serial/ftdi_sio.c
parentd1abaeb3be7b5fa6d7a1fbbd2e14e3310005c4c1 (diff)
downloadlinux-7a786b84790789eff5bad49e3f6c15f75b7bf691.tar.bz2
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 <tharvey@gateworks.com> Signed-off-by: Matthew Michilot <matthew.michilot@gmail.com> [ johan: fix copy-paste error in commit message ] Signed-off-by: Johan Hovold <johan@kernel.org>
Diffstat (limited to 'drivers/usb/serial/ftdi_sio.c')
-rw-r--r--drivers/usb/serial/ftdi_sio.c43
1 files changed, 43 insertions, 0 deletions
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;