diff options
Diffstat (limited to 'drivers/usb/serial/cp210x.c')
| -rw-r--r-- | drivers/usb/serial/cp210x.c | 245 |
1 files changed, 209 insertions, 36 deletions
diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c index 4a118eb13590..b9bc80700be7 100644 --- a/drivers/usb/serial/cp210x.c +++ b/drivers/usb/serial/cp210x.c @@ -224,9 +224,10 @@ MODULE_DEVICE_TABLE(usb, id_table); struct cp210x_serial_private { #ifdef CONFIG_GPIOLIB struct gpio_chip gc; - u8 config; - u8 gpio_mode; bool gpio_registered; + u8 gpio_pushpull; + u8 gpio_altfunc; + u8 gpio_input; #endif u8 partnum; speed_t max_speed; @@ -343,6 +344,7 @@ static struct usb_serial_driver * const serial_drivers[] = { #define CONTROL_WRITE_RTS 0x0200 /* CP210X_VENDOR_SPECIFIC values */ +#define CP210X_READ_2NCONFIG 0x000E #define CP210X_READ_LATCH 0x00C2 #define CP210X_GET_PARTNUM 0x370B #define CP210X_GET_PORTCONFIG 0x370C @@ -452,6 +454,12 @@ struct cp210x_config { #define CP2105_GPIO1_RXLED_MODE BIT(1) #define CP2105_GPIO1_RS485_MODE BIT(2) +/* CP2102N configuration array indices */ +#define CP210X_2NCONFIG_CONFIG_VERSION_IDX 2 +#define CP210X_2NCONFIG_GPIO_MODE_IDX 581 +#define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX 587 +#define CP210X_2NCONFIG_GPIO_CONTROL_IDX 600 + /* CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x2 bytes. */ struct cp210x_gpio_write { u8 mask; @@ -1313,17 +1321,8 @@ static int cp210x_gpio_request(struct gpio_chip *gc, unsigned int offset) struct usb_serial *serial = gpiochip_get_data(gc); struct cp210x_serial_private *priv = usb_get_serial_data(serial); - switch (offset) { - case 0: - if (priv->config & CP2105_GPIO0_TXLED_MODE) - return -ENODEV; - break; - case 1: - if (priv->config & (CP2105_GPIO1_RXLED_MODE | - CP2105_GPIO1_RS485_MODE)) - return -ENODEV; - break; - } + if (priv->gpio_altfunc & BIT(offset)) + return -ENODEV; return 0; } @@ -1331,10 +1330,15 @@ static int cp210x_gpio_request(struct gpio_chip *gc, unsigned int offset) static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio) { struct usb_serial *serial = gpiochip_get_data(gc); + struct cp210x_serial_private *priv = usb_get_serial_data(serial); + u8 req_type = REQTYPE_DEVICE_TO_HOST; int result; u8 buf; - result = cp210x_read_vendor_block(serial, REQTYPE_INTERFACE_TO_HOST, + if (priv->partnum == CP210X_PARTNUM_CP2105) + req_type = REQTYPE_INTERFACE_TO_HOST; + + result = cp210x_read_vendor_block(serial, req_type, CP210X_READ_LATCH, &buf, sizeof(buf)); if (result < 0) return result; @@ -1345,7 +1349,9 @@ static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio) static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value) { struct usb_serial *serial = gpiochip_get_data(gc); + struct cp210x_serial_private *priv = usb_get_serial_data(serial); struct cp210x_gpio_write buf; + int result; if (value == 1) buf.state = BIT(gpio); @@ -1354,25 +1360,68 @@ static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value) buf.mask = BIT(gpio); - cp210x_write_vendor_block(serial, REQTYPE_HOST_TO_INTERFACE, - CP210X_WRITE_LATCH, &buf, sizeof(buf)); + if (priv->partnum == CP210X_PARTNUM_CP2105) { + result = cp210x_write_vendor_block(serial, + REQTYPE_HOST_TO_INTERFACE, + CP210X_WRITE_LATCH, &buf, + sizeof(buf)); + } else { + u16 wIndex = buf.state << 8 | buf.mask; + + result = usb_control_msg(serial->dev, + usb_sndctrlpipe(serial->dev, 0), + CP210X_VENDOR_SPECIFIC, + REQTYPE_HOST_TO_DEVICE, + CP210X_WRITE_LATCH, + wIndex, + NULL, 0, USB_CTRL_SET_TIMEOUT); + } + + if (result < 0) { + dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n", + result); + } } static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio) { - /* Hardware does not support an input mode */ - return 0; + struct usb_serial *serial = gpiochip_get_data(gc); + struct cp210x_serial_private *priv = usb_get_serial_data(serial); + + return priv->gpio_input & BIT(gpio); } static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio) { - /* Hardware does not support an input mode */ - return -ENOTSUPP; + struct usb_serial *serial = gpiochip_get_data(gc); + struct cp210x_serial_private *priv = usb_get_serial_data(serial); + + if (priv->partnum == CP210X_PARTNUM_CP2105) { + /* hardware does not support an input mode */ + return -ENOTSUPP; + } + + /* push-pull pins cannot be changed to be inputs */ + if (priv->gpio_pushpull & BIT(gpio)) + return -EINVAL; + + /* make sure to release pin if it is being driven low */ + cp210x_gpio_set(gc, gpio, 1); + + priv->gpio_input |= BIT(gpio); + + return 0; } static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio, int value) { + struct usb_serial *serial = gpiochip_get_data(gc); + struct cp210x_serial_private *priv = usb_get_serial_data(serial); + + priv->gpio_input &= ~BIT(gpio); + cp210x_gpio_set(gc, gpio, value); + return 0; } @@ -1385,11 +1434,11 @@ static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio, /* Succeed only if in correct mode (this can't be set at runtime) */ if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) && - (priv->gpio_mode & BIT(gpio))) + (priv->gpio_pushpull & BIT(gpio))) return 0; if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) && - !(priv->gpio_mode & BIT(gpio))) + !(priv->gpio_pushpull & BIT(gpio))) return 0; return -ENOTSUPP; @@ -1402,12 +1451,13 @@ static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio, * this driver that provide GPIO do so in a way that does not impact other * signals and are thus expected to have very different initialisation. */ -static int cp2105_shared_gpio_init(struct usb_serial *serial) +static int cp2105_gpioconf_init(struct usb_serial *serial) { struct cp210x_serial_private *priv = usb_get_serial_data(serial); struct cp210x_pin_mode mode; struct cp210x_config config; u8 intf_num = cp210x_interface_num(serial); + u8 iface_config; int result; result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST, @@ -1424,20 +1474,26 @@ static int cp2105_shared_gpio_init(struct usb_serial *serial) /* 2 banks of GPIO - One for the pins taken from each serial port */ if (intf_num == 0) { - if (mode.eci == CP210X_PIN_MODE_MODEM) + if (mode.eci == CP210X_PIN_MODE_MODEM) { + /* mark all GPIOs of this interface as reserved */ + priv->gpio_altfunc = 0xff; return 0; + } - priv->config = config.eci_cfg; - priv->gpio_mode = (u8)((le16_to_cpu(config.gpio_mode) & + iface_config = config.eci_cfg; + priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) & CP210X_ECI_GPIO_MODE_MASK) >> CP210X_ECI_GPIO_MODE_OFFSET); priv->gc.ngpio = 2; } else if (intf_num == 1) { - if (mode.sci == CP210X_PIN_MODE_MODEM) + if (mode.sci == CP210X_PIN_MODE_MODEM) { + /* mark all GPIOs of this interface as reserved */ + priv->gpio_altfunc = 0xff; return 0; + } - priv->config = config.sci_cfg; - priv->gpio_mode = (u8)((le16_to_cpu(config.gpio_mode) & + iface_config = config.sci_cfg; + priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) & CP210X_SCI_GPIO_MODE_MASK) >> CP210X_SCI_GPIO_MODE_OFFSET); priv->gc.ngpio = 3; @@ -1445,6 +1501,125 @@ static int cp2105_shared_gpio_init(struct usb_serial *serial) return -ENODEV; } + /* mark all pins which are not in GPIO mode */ + if (iface_config & CP2105_GPIO0_TXLED_MODE) /* GPIO 0 */ + priv->gpio_altfunc |= BIT(0); + if (iface_config & (CP2105_GPIO1_RXLED_MODE | /* GPIO 1 */ + CP2105_GPIO1_RS485_MODE)) + priv->gpio_altfunc |= BIT(1); + + /* driver implementation for CP2105 only supports outputs */ + priv->gpio_input = 0; + + return 0; +} + +static int cp2102n_gpioconf_init(struct usb_serial *serial) +{ + struct cp210x_serial_private *priv = usb_get_serial_data(serial); + const u16 config_size = 0x02a6; + u8 gpio_rst_latch; + u8 config_version; + u8 gpio_pushpull; + u8 *config_buf; + u8 gpio_latch; + u8 gpio_ctrl; + int result; + u8 i; + + /* + * Retrieve device configuration from the device. + * The array received contains all customization settings done at the + * factory/manufacturer. Format of the array is documented at the + * time of writing at: + * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa + */ + config_buf = kmalloc(config_size, GFP_KERNEL); + if (!config_buf) + return -ENOMEM; + + result = cp210x_read_vendor_block(serial, + REQTYPE_DEVICE_TO_HOST, + CP210X_READ_2NCONFIG, + config_buf, + config_size); + if (result < 0) { + kfree(config_buf); + return result; + } + + config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX]; + gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX]; + gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX]; + gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX]; + + kfree(config_buf); + + /* Make sure this is a config format we understand. */ + if (config_version != 0x01) + return -ENOTSUPP; + + /* + * We only support 4 GPIOs even on the QFN28 package, because + * config locations of GPIOs 4-6 determined using reverse + * engineering revealed conflicting offsets with other + * documented functions. So we'll just play it safe for now. + */ + priv->gc.ngpio = 4; + + /* + * Get default pin states after reset. Needed so we can determine + * the direction of an open-drain pin. + */ + gpio_latch = (gpio_rst_latch >> 3) & 0x0f; + + /* 0 indicates open-drain mode, 1 is push-pull */ + priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f; + + /* 0 indicates GPIO mode, 1 is alternate function */ + priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f; + + /* + * The CP2102N does not strictly has input and output pin modes, + * it only knows open-drain and push-pull modes which is set at + * factory. An open-drain pin can function both as an + * input or an output. We emulate input mode for open-drain pins + * by making sure they are not driven low, and we do not allow + * push-pull pins to be set as an input. + */ + for (i = 0; i < priv->gc.ngpio; ++i) { + /* + * Set direction to "input" iff pin is open-drain and reset + * value is 1. + */ + if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i))) + priv->gpio_input |= BIT(i); + } + + return 0; +} + +static int cp210x_gpio_init(struct usb_serial *serial) +{ + struct cp210x_serial_private *priv = usb_get_serial_data(serial); + int result; + + switch (priv->partnum) { + case CP210X_PARTNUM_CP2105: + result = cp2105_gpioconf_init(serial); + break; + case CP210X_PARTNUM_CP2102N_QFN28: + case CP210X_PARTNUM_CP2102N_QFN24: + case CP210X_PARTNUM_CP2102N_QFN20: + result = cp2102n_gpioconf_init(serial); + break; + default: + return 0; + } + + if (result < 0) + return result; + priv->gc.label = "cp210x"; priv->gc.request = cp210x_gpio_request; priv->gc.get_direction = cp210x_gpio_direction_get; @@ -1477,7 +1652,7 @@ static void cp210x_gpio_remove(struct usb_serial *serial) #else -static int cp2105_shared_gpio_init(struct usb_serial *serial) +static int cp210x_gpio_init(struct usb_serial *serial) { return 0; } @@ -1588,12 +1763,10 @@ static int cp210x_attach(struct usb_serial *serial) cp210x_init_max_speed(serial); - if (priv->partnum == CP210X_PARTNUM_CP2105) { - result = cp2105_shared_gpio_init(serial); - if (result < 0) { - dev_err(&serial->interface->dev, - "GPIO initialisation failed, continuing without GPIO support\n"); - } + result = cp210x_gpio_init(serial); + if (result < 0) { + dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n", + result); } return 0; |