diff options
Diffstat (limited to 'drivers/tty/serial/8250/8250_exar.c')
| -rw-r--r-- | drivers/tty/serial/8250/8250_exar.c | 114 |
1 files changed, 99 insertions, 15 deletions
diff --git a/drivers/tty/serial/8250/8250_exar.c b/drivers/tty/serial/8250/8250_exar.c index edd6dfe055bf..597eb9d16f21 100644 --- a/drivers/tty/serial/8250/8250_exar.c +++ b/drivers/tty/serial/8250/8250_exar.c @@ -19,6 +19,7 @@ #include <linux/string.h> #include <linux/tty.h> #include <linux/8250_pci.h> +#include <linux/delay.h> #include <asm/byteorder.h> @@ -36,6 +37,8 @@ #define UART_EXAR_INT0 0x80 #define UART_EXAR_8XMODE 0x88 /* 8X sampling rate select */ +#define UART_EXAR_SLEEP 0x8b /* Sleep mode */ +#define UART_EXAR_DVID 0x8d /* Device identification */ #define UART_EXAR_FCTR 0x08 /* Feature Control Register */ #define UART_FCTR_EXAR_IRDA 0x10 /* IrDa data encode select */ @@ -127,18 +130,95 @@ struct exar8250 { int line[0]; }; +static void exar_pm(struct uart_port *port, unsigned int state, unsigned int old) +{ + /* + * Exar UARTs have a SLEEP register that enables or disables each UART + * to enter sleep mode separately. On the XR17V35x the register + * is accessible to each UART at the UART_EXAR_SLEEP offset, but + * the UART channel may only write to the corresponding bit. + */ + serial_port_out(port, UART_EXAR_SLEEP, state ? 0xff : 0); +} + +/* + * XR17V35x UARTs have an extra fractional divisor register (DLD) + * Calculate divisor with extra 4-bit fractional portion + */ +static unsigned int xr17v35x_get_divisor(struct uart_port *p, unsigned int baud, + unsigned int *frac) +{ + unsigned int quot_16; + + quot_16 = DIV_ROUND_CLOSEST(p->uartclk, baud); + *frac = quot_16 & 0x0f; + + return quot_16 >> 4; +} + +static void xr17v35x_set_divisor(struct uart_port *p, unsigned int baud, + unsigned int quot, unsigned int quot_frac) +{ + serial8250_do_set_divisor(p, baud, quot, quot_frac); + + /* Preserve bits not related to baudrate; DLD[7:4]. */ + quot_frac |= serial_port_in(p, 0x2) & 0xf0; + serial_port_out(p, 0x2, quot_frac); +} + +static void exar_shutdown(struct uart_port *port) +{ + unsigned char lsr; + bool tx_complete = 0; + struct uart_8250_port *up = up_to_u8250p(port); + struct circ_buf *xmit = &port->state->xmit; + int i = 0; + + do { + lsr = serial_in(up, UART_LSR); + if (lsr & (UART_LSR_TEMT | UART_LSR_THRE)) + tx_complete = 1; + else + tx_complete = 0; + usleep_range(1000, 1100); + } while (!uart_circ_empty(xmit) && !tx_complete && i++ < 1000); + + serial8250_do_shutdown(port); +} + static int default_setup(struct exar8250 *priv, struct pci_dev *pcidev, int idx, unsigned int offset, struct uart_8250_port *port) { const struct exar8250_board *board = priv->board; unsigned int bar = 0; + unsigned char status; port->port.iotype = UPIO_MEM; port->port.mapbase = pci_resource_start(pcidev, bar) + offset; port->port.membase = priv->virt + offset; port->port.regshift = board->reg_shift; + /* + * XR17V35x UARTs have an extra divisor register, DLD that gets enabled + * with when DLAB is set which will cause the device to incorrectly match + * and assign port type to PORT_16650. The EFR for this UART is found + * at offset 0x09. Instead check the Deice ID (DVID) register + * for a 2, 4 or 8 port UART. + */ + status = readb(port->port.membase + UART_EXAR_DVID); + if (status == 0x82 || status == 0x84 || status == 0x88) { + port->port.type = PORT_XR17V35X; + + port->port.get_divisor = xr17v35x_get_divisor; + port->port.set_divisor = xr17v35x_set_divisor; + } else { + port->port.type = PORT_XR17D15X; + } + + port->port.pm = exar_pm; + port->port.shutdown = exar_shutdown; + return 0; } @@ -434,6 +514,16 @@ static void pci_xr17v35x_exit(struct pci_dev *pcidev) port->port.private_data = NULL; } +static inline void exar_misc_clear(struct exar8250 *priv) +{ + /* Clear all PCI interrupts by reading INT0. No effect on IIR */ + readb(priv->virt + UART_EXAR_INT0); + + /* Clear INT0 for Expansion Interface slave ports, too */ + if (priv->board->num_ports > 8) + readb(priv->virt + 0x2000 + UART_EXAR_INT0); +} + /* * These Exar UARTs have an extra interrupt indicator that could fire for a * few interrupts that are not presented/cleared through IIR. One of which is @@ -445,14 +535,7 @@ static void pci_xr17v35x_exit(struct pci_dev *pcidev) */ static irqreturn_t exar_misc_handler(int irq, void *data) { - struct exar8250 *priv = data; - - /* Clear all PCI interrupts by reading INT0. No effect on IIR */ - readb(priv->virt + UART_EXAR_INT0); - - /* Clear INT0 for Expansion Interface slave ports, too */ - if (priv->board->num_ports > 8) - readb(priv->virt + 0x2000 + UART_EXAR_INT0); + exar_misc_clear(data); return IRQ_HANDLED; } @@ -478,9 +561,7 @@ exar_pci_probe(struct pci_dev *pcidev, const struct pci_device_id *ent) nr_ports = board->num_ports ? board->num_ports : pcidev->device & 0x0f; - priv = devm_kzalloc(&pcidev->dev, sizeof(*priv) + - sizeof(unsigned int) * nr_ports, - GFP_KERNEL); + priv = devm_kzalloc(&pcidev->dev, struct_size(priv, line, nr_ports), GFP_KERNEL); if (!priv) return -ENOMEM; @@ -496,8 +577,7 @@ exar_pci_probe(struct pci_dev *pcidev, const struct pci_device_id *ent) return rc; memset(&uart, 0, sizeof(uart)); - uart.port.flags = UPF_SKIP_TEST | UPF_BOOT_AUTOCONF | UPF_SHARE_IRQ - | UPF_EXAR_EFR; + uart.port.flags = UPF_SHARE_IRQ | UPF_EXAR_EFR | UPF_FIXED_TYPE | UPF_FIXED_PORT; uart.port.irq = pci_irq_vector(pcidev, 0); uart.port.dev = &pcidev->dev; @@ -506,6 +586,9 @@ exar_pci_probe(struct pci_dev *pcidev, const struct pci_device_id *ent) if (rc) return rc; + /* Clear interrupts */ + exar_misc_clear(priv); + for (i = 0; i < nr_ports && i < maxnr; i++) { rc = board->setup(priv, pcidev, &uart, i); if (rc) { @@ -561,10 +644,11 @@ static int __maybe_unused exar_suspend(struct device *dev) static int __maybe_unused exar_resume(struct device *dev) { - struct pci_dev *pcidev = to_pci_dev(dev); - struct exar8250 *priv = pci_get_drvdata(pcidev); + struct exar8250 *priv = dev_get_drvdata(dev); unsigned int i; + exar_misc_clear(priv); + for (i = 0; i < priv->nr; i++) if (priv->line[i] >= 0) serial8250_resume_port(priv->line[i]); |