/*
 *  Driver for 8250/16550-type serial ports
 *
 *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
 *
 *  Copyright (C) 2001 Russell King.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/serial_8250.h>
#include <linux/serial_reg.h>
#include <linux/dmaengine.h>

struct uart_8250_dma {
        int (*tx_dma)(struct uart_8250_port *p);
        int (*rx_dma)(struct uart_8250_port *p, unsigned int iir);

        /* Filter function */
        dma_filter_fn           fn;
        /* Parameter to the filter function */
        void                    *rx_param;
        void                    *tx_param;

        struct dma_slave_config rxconf;
        struct dma_slave_config txconf;

        struct dma_chan         *rxchan;
        struct dma_chan         *txchan;

        dma_addr_t              rx_addr;
        dma_addr_t              tx_addr;

        dma_cookie_t            rx_cookie;
        dma_cookie_t            tx_cookie;

        void                    *rx_buf;

        size_t                  rx_size;
        size_t                  tx_size;

        unsigned char           tx_running;
        unsigned char           tx_err;
        unsigned char           rx_running;
};

struct old_serial_port {
        unsigned int uart;
        unsigned int baud_base;
        unsigned int port;
        unsigned int irq;
        upf_t        flags;
        unsigned char hub6;
        unsigned char io_type;
        unsigned char __iomem *iomem_base;
        unsigned short iomem_reg_shift;
        unsigned long irqflags;
};

struct serial8250_config {
        const char      *name;
        unsigned short  fifo_size;
        unsigned short  tx_loadsz;
        unsigned char   fcr;
        unsigned char   rxtrig_bytes[UART_FCR_R_TRIG_MAX_STATE];
        unsigned int    flags;
};

#define UART_CAP_FIFO   (1 << 8)        /* UART has FIFO */
#define UART_CAP_EFR    (1 << 9)        /* UART has EFR */
#define UART_CAP_SLEEP  (1 << 10)       /* UART has IER sleep */
#define UART_CAP_AFE    (1 << 11)       /* MCR-based hw flow control */
#define UART_CAP_UUE    (1 << 12)       /* UART needs IER bit 6 set (Xscale) */
#define UART_CAP_RTOIE  (1 << 13)       /* UART needs IER bit 4 set (Xscale, Tegra) */
#define UART_CAP_HFIFO  (1 << 14)       /* UART has a "hidden" FIFO */
#define UART_CAP_RPM    (1 << 15)       /* Runtime PM is active while idle */

#define UART_BUG_QUOT   (1 << 0)        /* UART has buggy quot LSB */
#define UART_BUG_TXEN   (1 << 1)        /* UART has buggy TX IIR status */
#define UART_BUG_NOMSR  (1 << 2)        /* UART has buggy MSR status bits (Au1x00) */
#define UART_BUG_THRE   (1 << 3)        /* UART has buggy THRE reassertion */
#define UART_BUG_PARITY (1 << 4)        /* UART mishandles parity if FIFO enabled */

#define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8)

#ifdef CONFIG_SERIAL_8250_SHARE_IRQ
#define SERIAL8250_SHARE_IRQS 1
#else
#define SERIAL8250_SHARE_IRQS 0
#endif

#define SERIAL8250_PORT_FLAGS(_base, _irq, _flags)              \
        {                                                       \
                .iobase         = _base,                        \
                .irq            = _irq,                         \
                .uartclk        = 1843200,                      \
                .iotype         = UPIO_PORT,                    \
                .flags          = UPF_BOOT_AUTOCONF | (_flags), \
        }

#define SERIAL8250_PORT(_base, _irq) SERIAL8250_PORT_FLAGS(_base, _irq, 0)


static inline int serial_in(struct uart_8250_port *up, int offset)
{
        return up->port.serial_in(&up->port, offset);
}

static inline void serial_out(struct uart_8250_port *up, int offset, int value)
{
        up->port.serial_out(&up->port, offset, value);
}

void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p);

static inline int serial_dl_read(struct uart_8250_port *up)
{
        return up->dl_read(up);
}

static inline void serial_dl_write(struct uart_8250_port *up, int value)
{
        up->dl_write(up, value);
}

struct uart_8250_port *serial8250_get_port(int line);
void serial8250_rpm_get(struct uart_8250_port *p);
void serial8250_rpm_put(struct uart_8250_port *p);
int serial8250_em485_init(struct uart_8250_port *p);
void serial8250_em485_destroy(struct uart_8250_port *p);

#if defined(__alpha__) && !defined(CONFIG_PCI)
/*
 * Digital did something really horribly wrong with the OUT1 and OUT2
 * lines on at least some ALPHA's.  The failure mode is that if either
 * is cleared, the machine locks up with endless interrupts.
 */
#define ALPHA_KLUDGE_MCR  (UART_MCR_OUT2 | UART_MCR_OUT1)
#else
#define ALPHA_KLUDGE_MCR 0
#endif

#ifdef CONFIG_SERIAL_8250_PNP
int serial8250_pnp_init(void);
void serial8250_pnp_exit(void);
#else
static inline int serial8250_pnp_init(void) { return 0; }
static inline void serial8250_pnp_exit(void) { }
#endif

#ifdef CONFIG_ARCH_OMAP1
static inline int is_omap1_8250(struct uart_8250_port *pt)
{
        int res;

        switch (pt->port.mapbase) {
        case OMAP1_UART1_BASE:
        case OMAP1_UART2_BASE:
        case OMAP1_UART3_BASE:
                res = 1;
                break;
        default:
                res = 0;
                break;
        }

        return res;
}

static inline int is_omap1510_8250(struct uart_8250_port *pt)
{
        if (!cpu_is_omap1510())
                return 0;

        return is_omap1_8250(pt);
}
#else
static inline int is_omap1_8250(struct uart_8250_port *pt)
{
        return 0;
}
static inline int is_omap1510_8250(struct uart_8250_port *pt)
{
        return 0;
}
#endif

#ifdef CONFIG_SERIAL_8250_DMA
extern int serial8250_tx_dma(struct uart_8250_port *);
extern int serial8250_rx_dma(struct uart_8250_port *, unsigned int iir);
extern int serial8250_request_dma(struct uart_8250_port *);
extern void serial8250_release_dma(struct uart_8250_port *);
#else
static inline int serial8250_tx_dma(struct uart_8250_port *p)
{
        return -1;
}
static inline int serial8250_rx_dma(struct uart_8250_port *p, unsigned int iir)
{
        return -1;
}
static inline int serial8250_request_dma(struct uart_8250_port *p)
{
        return -1;
}
static inline void serial8250_release_dma(struct uart_8250_port *p) { }
#endif

static inline int ns16550a_goto_highspeed(struct uart_8250_port *up)
{
        unsigned char status;

        status = serial_in(up, 0x04); /* EXCR2 */
#define PRESL(x) ((x) & 0x30)
        if (PRESL(status) == 0x10) {
                /* already in high speed mode */
                return 0;
        } else {
                status &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */
                status |= 0x10;  /* 1.625 divisor for baud_base --> 921600 */
                serial_out(up, 0x04, status);
        }
        return 1;
}

static inline int serial_index(struct uart_port *port)
{
        return port->minor - 64;
}

#if 0
#define DEBUG_INTR(fmt...)      printk(fmt)
#else
#define DEBUG_INTR(fmt...)      do { } while (0)
#endif