diff options
Diffstat (limited to 'drivers/usb/serial/cp210x.c')
-rw-r--r-- | drivers/usb/serial/cp210x.c | 388 |
1 files changed, 385 insertions, 3 deletions
diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c index f5ee4ba4b33b..213ed3868fed 100644 --- a/drivers/usb/serial/cp210x.c +++ b/drivers/usb/serial/cp210x.c @@ -23,6 +23,9 @@ #include <linux/usb.h> #include <linux/uaccess.h> #include <linux/usb/serial.h> +#include <linux/gpio/driver.h> +#include <linux/bitops.h> +#include <linux/mutex.h> #define DRIVER_DESC "Silicon Labs CP210x RS232 serial adaptor driver" @@ -44,6 +47,9 @@ static int cp210x_tiocmset(struct tty_struct *, unsigned int, unsigned int); static int cp210x_tiocmset_port(struct usb_serial_port *port, unsigned int, unsigned int); static void cp210x_break_ctl(struct tty_struct *, int); +static int cp210x_attach(struct usb_serial *); +static void cp210x_disconnect(struct usb_serial *); +static void cp210x_release(struct usb_serial *); static int cp210x_port_probe(struct usb_serial_port *); static int cp210x_port_remove(struct usb_serial_port *); static void cp210x_dtr_rts(struct usb_serial_port *p, int on); @@ -208,6 +214,16 @@ static const struct usb_device_id id_table[] = { MODULE_DEVICE_TABLE(usb, id_table); +struct cp210x_serial_private { +#ifdef CONFIG_GPIOLIB + struct gpio_chip gc; + u8 config; + u8 gpio_mode; + u8 gpio_registered; +#endif + u8 partnum; +}; + struct cp210x_port_private { __u8 bInterfaceNumber; bool has_swapped_line_ctl; @@ -229,6 +245,9 @@ static struct usb_serial_driver cp210x_device = { .tx_empty = cp210x_tx_empty, .tiocmget = cp210x_tiocmget, .tiocmset = cp210x_tiocmset, + .attach = cp210x_attach, + .disconnect = cp210x_disconnect, + .release = cp210x_release, .port_probe = cp210x_port_probe, .port_remove = cp210x_port_remove, .dtr_rts = cp210x_dtr_rts @@ -271,6 +290,7 @@ static struct usb_serial_driver * const serial_drivers[] = { #define CP210X_SET_CHARS 0x19 #define CP210X_GET_BAUDRATE 0x1D #define CP210X_SET_BAUDRATE 0x1E +#define CP210X_VENDOR_SPECIFIC 0xFF /* CP210X_IFC_ENABLE */ #define UART_ENABLE 0x0001 @@ -313,6 +333,21 @@ static struct usb_serial_driver * const serial_drivers[] = { #define CONTROL_WRITE_DTR 0x0100 #define CONTROL_WRITE_RTS 0x0200 +/* CP210X_VENDOR_SPECIFIC values */ +#define CP210X_READ_LATCH 0x00C2 +#define CP210X_GET_PARTNUM 0x370B +#define CP210X_GET_PORTCONFIG 0x370C +#define CP210X_GET_DEVICEMODE 0x3711 +#define CP210X_WRITE_LATCH 0x37E1 + +/* Part number definitions */ +#define CP210X_PARTNUM_CP2101 0x01 +#define CP210X_PARTNUM_CP2102 0x02 +#define CP210X_PARTNUM_CP2103 0x03 +#define CP210X_PARTNUM_CP2104 0x04 +#define CP210X_PARTNUM_CP2105 0x05 +#define CP210X_PARTNUM_CP2108 0x08 + /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */ struct cp210x_comm_status { __le32 ulErrors; @@ -368,6 +403,60 @@ struct cp210x_flow_ctl { #define CP210X_SERIAL_RTS_ACTIVE 1 #define CP210X_SERIAL_RTS_FLOW_CTL 2 +/* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */ +struct cp210x_pin_mode { + u8 eci; + u8 sci; +} __packed; + +#define CP210X_PIN_MODE_MODEM 0 +#define CP210X_PIN_MODE_GPIO BIT(0) + +/* + * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes. + * Structure needs padding due to unused/unspecified bytes. + */ +struct cp210x_config { + __le16 gpio_mode; + u8 __pad0[2]; + __le16 reset_state; + u8 __pad1[4]; + __le16 suspend_state; + u8 sci_cfg; + u8 eci_cfg; + u8 device_cfg; +} __packed; + +/* GPIO modes */ +#define CP210X_SCI_GPIO_MODE_OFFSET 9 +#define CP210X_SCI_GPIO_MODE_MASK GENMASK(11, 9) + +#define CP210X_ECI_GPIO_MODE_OFFSET 2 +#define CP210X_ECI_GPIO_MODE_MASK GENMASK(3, 2) + +/* CP2105 port configuration values */ +#define CP2105_GPIO0_TXLED_MODE BIT(0) +#define CP2105_GPIO1_RXLED_MODE BIT(1) +#define CP2105_GPIO1_RS485_MODE BIT(2) + +/* CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x2 bytes. */ +struct cp210x_gpio_write { + u8 mask; + u8 state; +} __packed; + +/* + * Helper to get interface number when we only have struct usb_serial. + */ +static u8 cp210x_interface_num(struct usb_serial *serial) +{ + struct usb_host_interface *cur_altsetting; + + cur_altsetting = serial->interface->cur_altsetting; + + return cur_altsetting->desc.bInterfaceNumber; +} + /* * Reads a variable-sized block of CP210X_ registers, identified by req. * Returns data into buf in native USB byte order. @@ -464,6 +553,40 @@ static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val) } /* + * Reads a variable-sized vendor block of CP210X_ registers, identified by val. + * Returns data into buf in native USB byte order. + */ +static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val, + void *buf, int bufsize) +{ + void *dmabuf; + int result; + + dmabuf = kmalloc(bufsize, GFP_KERNEL); + if (!dmabuf) + return -ENOMEM; + + result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0), + CP210X_VENDOR_SPECIFIC, type, val, + cp210x_interface_num(serial), dmabuf, bufsize, + USB_CTRL_GET_TIMEOUT); + if (result == bufsize) { + memcpy(buf, dmabuf, bufsize); + result = 0; + } else { + dev_err(&serial->interface->dev, + "failed to get vendor val 0x%04x size %d: %d\n", val, + bufsize, result); + if (result >= 0) + result = -EIO; + } + + kfree(dmabuf); + + return result; +} + +/* * Writes any 16-bit CP210X_ register (req) whose value is passed * entirely in the wValue field of the USB request. */ @@ -532,6 +655,42 @@ static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val) return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val)); } +#ifdef CONFIG_GPIOLIB +/* + * Writes a variable-sized vendor block of CP210X_ registers, identified by val. + * Data in buf must be in native USB byte order. + */ +static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type, + u16 val, void *buf, int bufsize) +{ + void *dmabuf; + int result; + + dmabuf = kmemdup(buf, bufsize, GFP_KERNEL); + if (!dmabuf) + return -ENOMEM; + + result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), + CP210X_VENDOR_SPECIFIC, type, val, + cp210x_interface_num(serial), dmabuf, bufsize, + USB_CTRL_SET_TIMEOUT); + + kfree(dmabuf); + + if (result == bufsize) { + result = 0; + } else { + dev_err(&serial->interface->dev, + "failed to set vendor val 0x%04x size %d: %d\n", val, + bufsize, result); + if (result >= 0) + result = -EIO; + } + + return result; +} +#endif + /* * Detect CP2108 GET_LINE_CTL bug and activate workaround. * Write a known good value 0x800, read it back. @@ -1098,10 +1257,188 @@ static void cp210x_break_ctl(struct tty_struct *tty, int break_state) cp210x_write_u16_reg(port, CP210X_SET_BREAK, state); } +#ifdef CONFIG_GPIOLIB +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; + } + + return 0; +} + +static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio) +{ + struct usb_serial *serial = gpiochip_get_data(gc); + int result; + u8 buf; + + result = cp210x_read_vendor_block(serial, REQTYPE_INTERFACE_TO_HOST, + CP210X_READ_LATCH, &buf, sizeof(buf)); + if (result < 0) + return result; + + return !!(buf & BIT(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_gpio_write buf; + + if (value == 1) + buf.state = BIT(gpio); + else + buf.state = 0; + + buf.mask = BIT(gpio); + + cp210x_write_vendor_block(serial, REQTYPE_HOST_TO_INTERFACE, + CP210X_WRITE_LATCH, &buf, sizeof(buf)); +} + +static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio) +{ + /* Hardware does not support an input mode */ + return 0; +} + +static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio) +{ + /* Hardware does not support an input mode */ + return -ENOTSUPP; +} + +static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio, + int value) +{ + return 0; +} + +static int cp210x_gpio_set_single_ended(struct gpio_chip *gc, unsigned int gpio, + enum single_ended_mode mode) +{ + struct usb_serial *serial = gpiochip_get_data(gc); + struct cp210x_serial_private *priv = usb_get_serial_data(serial); + + /* Succeed only if in correct mode (this can't be set at runtime) */ + if ((mode == LINE_MODE_PUSH_PULL) && (priv->gpio_mode & BIT(gpio))) + return 0; + + if ((mode == LINE_MODE_OPEN_DRAIN) && !(priv->gpio_mode & BIT(gpio))) + return 0; + + return -ENOTSUPP; +} + +/* + * This function is for configuring GPIO using shared pins, where other signals + * are made unavailable by configuring the use of GPIO. This is believed to be + * only applicable to the cp2105 at this point, the other devices supported by + * 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) +{ + 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); + int result; + + result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST, + CP210X_GET_DEVICEMODE, &mode, + sizeof(mode)); + if (result < 0) + return result; + + result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST, + CP210X_GET_PORTCONFIG, &config, + sizeof(config)); + if (result < 0) + return result; + + /* 2 banks of GPIO - One for the pins taken from each serial port */ + if (intf_num == 0) { + if (mode.eci == CP210X_PIN_MODE_MODEM) + return 0; + + priv->config = config.eci_cfg; + priv->gpio_mode = (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) + return 0; + + priv->config = config.sci_cfg; + priv->gpio_mode = (u8)((le16_to_cpu(config.gpio_mode) & + CP210X_SCI_GPIO_MODE_MASK) >> + CP210X_SCI_GPIO_MODE_OFFSET); + priv->gc.ngpio = 3; + } else { + return -ENODEV; + } + + priv->gc.label = "cp210x"; + priv->gc.request = cp210x_gpio_request; + priv->gc.get_direction = cp210x_gpio_direction_get; + priv->gc.direction_input = cp210x_gpio_direction_input; + priv->gc.direction_output = cp210x_gpio_direction_output; + priv->gc.get = cp210x_gpio_get; + priv->gc.set = cp210x_gpio_set; + priv->gc.set_single_ended = cp210x_gpio_set_single_ended; + priv->gc.owner = THIS_MODULE; + priv->gc.parent = &serial->interface->dev; + priv->gc.base = -1; + priv->gc.can_sleep = true; + + result = gpiochip_add_data(&priv->gc, serial); + if (!result) + priv->gpio_registered = 1; + + return result; +} + +static void cp210x_gpio_remove(struct usb_serial *serial) +{ + struct cp210x_serial_private *priv = usb_get_serial_data(serial); + + if (priv->gpio_registered) { + gpiochip_remove(&priv->gc); + priv->gpio_registered = 0; + } +} + +#else + +static int cp2105_shared_gpio_init(struct usb_serial *serial) +{ + return 0; +} + +static void cp210x_gpio_remove(struct usb_serial *serial) +{ + /* Nothing to do */ +} + +#endif + static int cp210x_port_probe(struct usb_serial_port *port) { struct usb_serial *serial = port->serial; - struct usb_host_interface *cur_altsetting; struct cp210x_port_private *port_priv; int ret; @@ -1109,8 +1446,7 @@ static int cp210x_port_probe(struct usb_serial_port *port) if (!port_priv) return -ENOMEM; - cur_altsetting = serial->interface->cur_altsetting; - port_priv->bInterfaceNumber = cur_altsetting->desc.bInterfaceNumber; + port_priv->bInterfaceNumber = cp210x_interface_num(serial); usb_set_serial_port_data(port, port_priv); @@ -1133,6 +1469,52 @@ static int cp210x_port_remove(struct usb_serial_port *port) return 0; } +static int cp210x_attach(struct usb_serial *serial) +{ + int result; + struct cp210x_serial_private *priv; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST, + CP210X_GET_PARTNUM, &priv->partnum, + sizeof(priv->partnum)); + if (result < 0) + goto err_free_priv; + + usb_set_serial_data(serial, priv); + + 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"); + } + } + + return 0; +err_free_priv: + kfree(priv); + + return result; +} + +static void cp210x_disconnect(struct usb_serial *serial) +{ + cp210x_gpio_remove(serial); +} + +static void cp210x_release(struct usb_serial *serial) +{ + struct cp210x_serial_private *priv = usb_get_serial_data(serial); + + cp210x_gpio_remove(serial); + + kfree(priv); +} + module_usb_serial_driver(serial_drivers, id_table); MODULE_DESCRIPTION(DRIVER_DESC); |