LXR linux/drivers/tty/serial/8250/8250.h

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 *  Driver for 8250/16550-type serial ports
   4 *
   5 *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
   6 *
   7 *  Copyright (C) 2001 Russell King.
   8 */
   9
  10#include <linux/serial_8250.h>
  11#include <linux/serial_reg.h>
  12#include <linux/dmaengine.h>
  13
  14#include "../serial_mctrl_gpio.h"
  15
  16struct uart_8250_dma {
  17        int (*tx_dma)(struct uart_8250_port *p);
  18        int (*rx_dma)(struct uart_8250_port *p);
  19
  20        /* Filter function */
  21        dma_filter_fn           fn;
  22        /* Parameter to the filter function */
  23        void                    *rx_param;
  24        void                    *tx_param;
  25
  26        struct dma_slave_config rxconf;
  27        struct dma_slave_config txconf;
  28
  29        struct dma_chan         *rxchan;
  30        struct dma_chan         *txchan;
  31
  32        /* Device address base for DMA operations */
  33        phys_addr_t             rx_dma_addr;
  34        phys_addr_t             tx_dma_addr;
  35
  36        /* DMA address of the buffer in memory */
  37        dma_addr_t              rx_addr;
  38        dma_addr_t              tx_addr;
  39
  40        dma_cookie_t            rx_cookie;
  41        dma_cookie_t            tx_cookie;
  42
  43        void                    *rx_buf;
  44
  45        size_t                  rx_size;
  46        size_t                  tx_size;
  47
  48        unsigned char           tx_running;
  49        unsigned char           tx_err;
  50        unsigned char           rx_running;
  51};
  52
  53struct old_serial_port {
  54        unsigned int uart;
  55        unsigned int baud_base;
  56        unsigned int port;
  57        unsigned int irq;
  58        upf_t        flags;
  59        unsigned char io_type;
  60        unsigned char __iomem *iomem_base;
  61        unsigned short iomem_reg_shift;
  62};
  63
  64struct serial8250_config {
  65        const char      *name;
  66        unsigned short  fifo_size;
  67        unsigned short  tx_loadsz;
  68        unsigned char   fcr;
  69        unsigned char   rxtrig_bytes[UART_FCR_R_TRIG_MAX_STATE];
  70        unsigned int    flags;
  71};
  72
  73#define UART_CAP_FIFO   (1 << 8)        /* UART has FIFO */
  74#define UART_CAP_EFR    (1 << 9)        /* UART has EFR */
  75#define UART_CAP_SLEEP  (1 << 10)       /* UART has IER sleep */
  76#define UART_CAP_AFE    (1 << 11)       /* MCR-based hw flow control */
  77#define UART_CAP_UUE    (1 << 12)       /* UART needs IER bit 6 set (Xscale) */
  78#define UART_CAP_RTOIE  (1 << 13)       /* UART needs IER bit 4 set (Xscale, Tegra) */
  79#define UART_CAP_HFIFO  (1 << 14)       /* UART has a "hidden" FIFO */
  80#define UART_CAP_RPM    (1 << 15)       /* Runtime PM is active while idle */
  81#define UART_CAP_IRDA   (1 << 16)       /* UART supports IrDA line discipline */
  82#define UART_CAP_MINI   (1 << 17)       /* Mini UART on BCM283X family lacks:
  83                                         * STOP PARITY EPAR SPAR WLEN5 WLEN6
  84                                         */
  85
  86#define UART_BUG_QUOT   (1 << 0)        /* UART has buggy quot LSB */
  87#define UART_BUG_TXEN   (1 << 1)        /* UART has buggy TX IIR status */
  88#define UART_BUG_NOMSR  (1 << 2)        /* UART has buggy MSR status bits (Au1x00) */
  89#define UART_BUG_THRE   (1 << 3)        /* UART has buggy THRE reassertion */
  90#define UART_BUG_PARITY (1 << 4)        /* UART mishandles parity if FIFO enabled */
  91
  92
  93#ifdef CONFIG_SERIAL_8250_SHARE_IRQ
  94#define SERIAL8250_SHARE_IRQS 1
  95#else
  96#define SERIAL8250_SHARE_IRQS 0
  97#endif
  98
  99#define SERIAL8250_PORT_FLAGS(_base, _irq, _flags)              \
 100        {                                                       \
 101                .iobase         = _base,                        \
 102                .irq            = _irq,                         \
 103                .uartclk        = 1843200,                      \
 104                .iotype         = UPIO_PORT,                    \
 105                .flags          = UPF_BOOT_AUTOCONF | (_flags), \
 106        }
 107
 108#define SERIAL8250_PORT(_base, _irq) SERIAL8250_PORT_FLAGS(_base, _irq, 0)
 109
 110
 111static inline int serial_in(struct uart_8250_port *up, int offset)
 112{
 113        return up->port.serial_in(&up->port, offset);
 114}
 115
 116static inline void serial_out(struct uart_8250_port *up, int offset, int value)
 117{
 118        up->port.serial_out(&up->port, offset, value);
 119}
 120
 121void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p);
 122
 123static inline int serial_dl_read(struct uart_8250_port *up)
 124{
 125        return up->dl_read(up);
 126}
 127
 128static inline void serial_dl_write(struct uart_8250_port *up, int value)
 129{
 130        up->dl_write(up, value);
 131}
 132
 133static inline bool serial8250_set_THRI(struct uart_8250_port *up)
 134{
 135        if (up->ier & UART_IER_THRI)
 136                return false;
 137        up->ier |= UART_IER_THRI;
 138        serial_out(up, UART_IER, up->ier);
 139        return true;
 140}
 141
 142static inline bool serial8250_clear_THRI(struct uart_8250_port *up)
 143{
 144        if (!(up->ier & UART_IER_THRI))
 145                return false;
 146        up->ier &= ~UART_IER_THRI;
 147        serial_out(up, UART_IER, up->ier);
 148        return true;
 149}
 150
 151struct uart_8250_port *serial8250_get_port(int line);
 152
 153void serial8250_rpm_get(struct uart_8250_port *p);
 154void serial8250_rpm_put(struct uart_8250_port *p);
 155
 156void serial8250_rpm_get_tx(struct uart_8250_port *p);
 157void serial8250_rpm_put_tx(struct uart_8250_port *p);
 158
 159int serial8250_em485_init(struct uart_8250_port *p);
 160void serial8250_em485_destroy(struct uart_8250_port *p);
 161
 162/* MCR <-> TIOCM conversion */
 163static inline int serial8250_TIOCM_to_MCR(int tiocm)
 164{
 165        int mcr = 0;
 166
 167        if (tiocm & TIOCM_RTS)
 168                mcr |= UART_MCR_RTS;
 169        if (tiocm & TIOCM_DTR)
 170                mcr |= UART_MCR_DTR;
 171        if (tiocm & TIOCM_OUT1)
 172                mcr |= UART_MCR_OUT1;
 173        if (tiocm & TIOCM_OUT2)
 174                mcr |= UART_MCR_OUT2;
 175        if (tiocm & TIOCM_LOOP)
 176                mcr |= UART_MCR_LOOP;
 177
 178        return mcr;
 179}
 180
 181static inline int serial8250_MCR_to_TIOCM(int mcr)
 182{
 183        int tiocm = 0;
 184
 185        if (mcr & UART_MCR_RTS)
 186                tiocm |= TIOCM_RTS;
 187        if (mcr & UART_MCR_DTR)
 188                tiocm |= TIOCM_DTR;
 189        if (mcr & UART_MCR_OUT1)
 190                tiocm |= TIOCM_OUT1;
 191        if (mcr & UART_MCR_OUT2)
 192                tiocm |= TIOCM_OUT2;
 193        if (mcr & UART_MCR_LOOP)
 194                tiocm |= TIOCM_LOOP;
 195
 196        return tiocm;
 197}
 198
 199/* MSR <-> TIOCM conversion */
 200static inline int serial8250_MSR_to_TIOCM(int msr)
 201{
 202        int tiocm = 0;
 203
 204        if (msr & UART_MSR_DCD)
 205                tiocm |= TIOCM_CAR;
 206        if (msr & UART_MSR_RI)
 207                tiocm |= TIOCM_RNG;
 208        if (msr & UART_MSR_DSR)
 209                tiocm |= TIOCM_DSR;
 210        if (msr & UART_MSR_CTS)
 211                tiocm |= TIOCM_CTS;
 212
 213        return tiocm;
 214}
 215
 216static inline void serial8250_out_MCR(struct uart_8250_port *up, int value)
 217{
 218        serial_out(up, UART_MCR, value);
 219
 220        if (up->gpios)
 221                mctrl_gpio_set(up->gpios, serial8250_MCR_to_TIOCM(value));
 222}
 223
 224static inline int serial8250_in_MCR(struct uart_8250_port *up)
 225{
 226        int mctrl;
 227
 228        mctrl = serial_in(up, UART_MCR);
 229
 230        if (up->gpios) {
 231                unsigned int mctrl_gpio = 0;
 232
 233                mctrl_gpio = mctrl_gpio_get_outputs(up->gpios, &mctrl_gpio);
 234                mctrl |= serial8250_TIOCM_to_MCR(mctrl_gpio);
 235        }
 236
 237        return mctrl;
 238}
 239
 240#if defined(__alpha__) && !defined(CONFIG_PCI)
 241/*
 242 * Digital did something really horribly wrong with the OUT1 and OUT2
 243 * lines on at least some ALPHA's.  The failure mode is that if either
 244 * is cleared, the machine locks up with endless interrupts.
 245 */
 246#define ALPHA_KLUDGE_MCR  (UART_MCR_OUT2 | UART_MCR_OUT1)
 247#else
 248#define ALPHA_KLUDGE_MCR 0
 249#endif
 250
 251#ifdef CONFIG_SERIAL_8250_PNP
 252int serial8250_pnp_init(void);
 253void serial8250_pnp_exit(void);
 254#else
 255static inline int serial8250_pnp_init(void) { return 0; }
 256static inline void serial8250_pnp_exit(void) { }
 257#endif
 258
 259#ifdef CONFIG_SERIAL_8250_FINTEK
 260int fintek_8250_probe(struct uart_8250_port *uart);
 261#else
 262static inline int fintek_8250_probe(struct uart_8250_port *uart) { return 0; }
 263#endif
 264
 265#ifdef CONFIG_ARCH_OMAP1
 266static inline int is_omap1_8250(struct uart_8250_port *pt)
 267{
 268        int res;
 269
 270        switch (pt->port.mapbase) {
 271        case OMAP1_UART1_BASE:
 272        case OMAP1_UART2_BASE:
 273        case OMAP1_UART3_BASE:
 274                res = 1;
 275                break;
 276        default:
 277                res = 0;
 278                break;
 279        }
 280
 281        return res;
 282}
 283
 284static inline int is_omap1510_8250(struct uart_8250_port *pt)
 285{
 286        if (!cpu_is_omap1510())
 287                return 0;
 288
 289        return is_omap1_8250(pt);
 290}
 291#else
 292static inline int is_omap1_8250(struct uart_8250_port *pt)
 293{
 294        return 0;
 295}
 296static inline int is_omap1510_8250(struct uart_8250_port *pt)
 297{
 298        return 0;
 299}
 300#endif
 301
 302#ifdef CONFIG_SERIAL_8250_DMA
 303extern int serial8250_tx_dma(struct uart_8250_port *);
 304extern int serial8250_rx_dma(struct uart_8250_port *);
 305extern void serial8250_rx_dma_flush(struct uart_8250_port *);
 306extern int serial8250_request_dma(struct uart_8250_port *);
 307extern void serial8250_release_dma(struct uart_8250_port *);
 308#else
 309static inline int serial8250_tx_dma(struct uart_8250_port *p)
 310{
 311        return -1;
 312}
 313static inline int serial8250_rx_dma(struct uart_8250_port *p)
 314{
 315        return -1;
 316}
 317static inline void serial8250_rx_dma_flush(struct uart_8250_port *p) { }
 318static inline int serial8250_request_dma(struct uart_8250_port *p)
 319{
 320        return -1;
 321}
 322static inline void serial8250_release_dma(struct uart_8250_port *p) { }
 323#endif
 324
 325static inline int ns16550a_goto_highspeed(struct uart_8250_port *up)
 326{
 327        unsigned char status;
 328
 329        status = serial_in(up, 0x04); /* EXCR2 */
 330#define PRESL(x) ((x) & 0x30)
 331        if (PRESL(status) == 0x10) {
 332                /* already in high speed mode */
 333                return 0;
 334        } else {
 335                status &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */
 336                status |= 0x10;  /* 1.625 divisor for baud_base --> 921600 */
 337                serial_out(up, 0x04, status);
 338        }
 339        return 1;
 340}
 341
 342static inline int serial_index(struct uart_port *port)
 343{
 344        return port->minor - 64;
 345}
 346