From: Stefan Agner <stefan@xxxxxxxx> commit 6f7ec77cc8b64ff5037c1945e4650c65c458037d upstream. The QFN20 part has a different GPIO/port function assignment. The configuration struct bit field ordered as TX/RX/RS485/WAKEUP/CLK which exactly matches GPIO0-3 for QFN24/28. However, QFN20 has a different GPIO to primary function assignment. Special case QFN20 to follow to properly detect which GPIOs are available. Signed-off-by: Stefan Agner <stefan@xxxxxxxx> Link: https://lore.kernel.org/r/51830b2b24118eb0f77c5c9ac64ffb2f519dbb1d.1622218300.git.stefan@xxxxxxxx Fixes: c8acfe0aadbe ("USB: serial: cp210x: implement GPIO support for CP2102N") Cc: stable@xxxxxxxxxxxxxxx # 4.19 Signed-off-by: Johan Hovold <johan@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/serial/cp210x.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) --- a/drivers/usb/serial/cp210x.c +++ b/drivers/usb/serial/cp210x.c @@ -537,6 +537,12 @@ struct cp210x_single_port_config { #define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX 587 #define CP210X_2NCONFIG_GPIO_CONTROL_IDX 600 +/* CP2102N QFN20 port configuration values */ +#define CP2102N_QFN20_GPIO2_TXLED_MODE BIT(2) +#define CP2102N_QFN20_GPIO3_RXLED_MODE BIT(3) +#define CP2102N_QFN20_GPIO1_RS485_MODE BIT(4) +#define CP2102N_QFN20_GPIO0_CLK_MODE BIT(6) + /* CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x2 bytes. */ struct cp210x_gpio_write { u8 mask; @@ -1726,7 +1732,19 @@ static int cp2102n_gpioconf_init(struct priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f; /* 0 indicates GPIO mode, 1 is alternate function */ - priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f; + if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN20) { + /* QFN20 is special... */ + if (gpio_ctrl & CP2102N_QFN20_GPIO0_CLK_MODE) /* GPIO 0 */ + priv->gpio_altfunc |= BIT(0); + if (gpio_ctrl & CP2102N_QFN20_GPIO1_RS485_MODE) /* GPIO 1 */ + priv->gpio_altfunc |= BIT(1); + if (gpio_ctrl & CP2102N_QFN20_GPIO2_TXLED_MODE) /* GPIO 2 */ + priv->gpio_altfunc |= BIT(2); + if (gpio_ctrl & CP2102N_QFN20_GPIO3_RXLED_MODE) /* GPIO 3 */ + priv->gpio_altfunc |= BIT(3); + } else { + priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f; + } if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN28) { /*
