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/bits.h>
  11#include <linux/serial_8250.h>
  12#include <linux/serial_reg.h>
  13#include <linux/dmaengine.h>
  14
  15#include "../serial_mctrl_gpio.h"
  16
  17struct uart_8250_dma {
  18        int (*tx_dma)(struct uart_8250_port *p);
  19        int (*rx_dma)(struct uart_8250_port *p);
  20
  21        /* Filter function */
  22        dma_filter_fn           fn;
  23        /* Parameter to the filter function */
  24        void                    *rx_param;
  25        void                    *tx_param;
  26
  27        struct dma_slave_config rxconf;
  28        struct dma_slave_config txconf;
  29
  30        struct dma_chan         *rxchan;
  31        struct dma_chan         *txchan;
  32
  33        /* Device address base for DMA operations */
  34        phys_addr_t             rx_dma_addr;
  35        phys_addr_t             tx_dma_addr;
  36
  37        /* DMA address of the buffer in memory */
  38        dma_addr_t              rx_addr;
  39        dma_addr_t              tx_addr;
  40
  41        dma_cookie_t            rx_cookie;
  42        dma_cookie_t            tx_cookie;
  43
  44        void                    *rx_buf;
  45
  46        size_t                  rx_size;
  47        size_t                  tx_size;
  48
  49        unsigned char           tx_running;
  50        unsigned char           tx_err;
  51        unsigned char           rx_running;
  52};
  53
  54struct old_serial_port {
  55        unsigned int uart;
  56        unsigned int baud_base;
  57        unsigned int port;
  58        unsigned int irq;
  59        upf_t        flags;
  60        unsigned char io_type;
  61        unsigned char __iomem *iomem_base;
  62        unsigned short iomem_reg_shift;
  63};
  64
  65struct serial8250_config {
  66        const char      *name;
  67        unsigned short  fifo_size;
  68        unsigned short  tx_loadsz;
  69        unsigned char   fcr;
  70        unsigned char   rxtrig_bytes[UART_FCR_R_TRIG_MAX_STATE];
  71        unsigned int    flags;
  72};
  73
  74#define UART_CAP_FIFO   BIT(8)  /* UART has FIFO */
  75#define UART_CAP_EFR    BIT(9)  /* UART has EFR */
  76#define UART_CAP_SLEEP  BIT(10) /* UART has IER sleep */
  77#define UART_CAP_AFE    BIT(11) /* MCR-based hw flow control */
  78#define UART_CAP_UUE    BIT(12) /* UART needs IER bit 6 set (Xscale) */
  79#define UART_CAP_RTOIE  BIT(13) /* UART needs IER bit 4 set (Xscale, Tegra) */
  80#define UART_CAP_HFIFO  BIT(14) /* UART has a "hidden" FIFO */
  81#define UART_CAP_RPM    BIT(15) /* Runtime PM is active while idle */
  82#define UART_CAP_IRDA   BIT(16) /* UART supports IrDA line discipline */
  83#define UART_CAP_MINI   BIT(17) /* Mini UART on BCM283X family lacks:
  84                                         * STOP PARITY EPAR SPAR WLEN5 WLEN6
  85                                         */
  86
  87#define UART_BUG_QUOT   BIT(0)  /* UART has buggy quot LSB */
  88#define UART_BUG_TXEN   BIT(1)  /* UART has buggy TX IIR status */
  89#define UART_BUG_NOMSR  BIT(2)  /* UART has buggy MSR status bits (Au1x00) */
  90#define UART_BUG_THRE   BIT(3)  /* UART has buggy THRE reassertion */
  91#define UART_BUG_PARITY BIT(4)  /* UART mishandles parity if FIFO enabled */
  92#define UART_BUG_TXRACE BIT(5)  /* UART Tx fails to set remote DR */
  93
  94
  95#ifdef CONFIG_SERIAL_8250_SHARE_IRQ
  96#define SERIAL8250_SHARE_IRQS 1
  97#else
  98#define SERIAL8250_SHARE_IRQS 0
  99#endif
 100
 101#define SERIAL8250_PORT_FLAGS(_base, _irq, _flags)              \
 102        {                                                       \
 103                .iobase         = _base,                        \
 104                .irq            = _irq,                         \
 105                .uartclk        = 1843200,                      \
 106                .iotype         = UPIO_PORT,                    \
 107                .flags          = UPF_BOOT_AUTOCONF | (_flags), \
 108        }
 109
 110#define SERIAL8250_PORT(_base, _irq) SERIAL8250_PORT_FLAGS(_base, _irq, 0)
 111
 112
 113static inline int serial_in(struct uart_8250_port *up, int offset)
 114{
 115        return up->port.serial_in(&up->port, offset);
 116}
 117
 118static inline void serial_out(struct uart_8250_port *up, int offset, int value)
 119{
 120        up->port.serial_out(&up->port, offset, value);
 121}
 122
 123void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p);
 124
 125static inline int serial_dl_read(struct uart_8250_port *up)
 126{
 127        return up->dl_read(up);
 128}
 129
 130static inline void serial_dl_write(struct uart_8250_port *up, int value)
 131{
 132        up->dl_write(up, value);
 133}
 134
 135static inline bool serial8250_set_THRI(struct uart_8250_port *up)
 136{
 137        if (up->ier & UART_IER_THRI)
 138                return false;
 139        up->ier |= UART_IER_THRI;
 140        serial_out(up, UART_IER, up->ier);
 141        return true;
 142}
 143
 144static inline bool serial8250_clear_THRI(struct uart_8250_port *up)
 145{
 146        if (!(up->ier & UART_IER_THRI))
 147                return false;
 148        up->ier &= ~UART_IER_THRI;
 149        serial_out(up, UART_IER, up->ier);
 150        return true;
 151}
 152
 153struct uart_8250_port *serial8250_get_port(int line);
 154
 155void serial8250_rpm_get(struct uart_8250_port *p);
 156void serial8250_rpm_put(struct uart_8250_port *p);
 157
 158void serial8250_rpm_get_tx(struct uart_8250_port *p);
 159void serial8250_rpm_put_tx(struct uart_8250_port *p);
 160
 161int serial8250_em485_config(struct uart_port *port, struct serial_rs485 *rs485);
 162void serial8250_em485_start_tx(struct uart_8250_port *p);
 163void serial8250_em485_stop_tx(struct uart_8250_port *p);
 164void serial8250_em485_destroy(struct uart_8250_port *p);
 165
 166/* MCR <-> TIOCM conversion */
 167static inline int serial8250_TIOCM_to_MCR(int tiocm)
 168{
 169        int mcr = 0;
 170
 171        if (tiocm & TIOCM_RTS)
 172                mcr |= UART_MCR_RTS;
 173        if (tiocm & TIOCM_DTR)
 174                mcr |= UART_MCR_DTR;
 175        if (tiocm & TIOCM_OUT1)
 176                mcr |= UART_MCR_OUT1;
 177        if (tiocm & TIOCM_OUT2)
 178                mcr |= UART_MCR_OUT2;
 179        if (tiocm & TIOCM_LOOP)
 180                mcr |= UART_MCR_LOOP;
 181
 182        return mcr;
 183}
 184
 185static inline int serial8250_MCR_to_TIOCM(int mcr)
 186{
 187        int tiocm = 0;
 188
 189        if (mcr & UART_MCR_RTS)
 190                tiocm |= TIOCM_RTS;
 191        if (mcr & UART_MCR_DTR)
 192                tiocm |= TIOCM_DTR;
 193        if (mcr & UART_MCR_OUT1)
 194                tiocm |= TIOCM_OUT1;
 195        if (mcr & UART_MCR_OUT2)
 196                tiocm |= TIOCM_OUT2;
 197        if (mcr & UART_MCR_LOOP)
 198                tiocm |= TIOCM_LOOP;
 199
 200        return tiocm;
 201}
 202
 203/* MSR <-> TIOCM conversion */
 204static inline int serial8250_MSR_to_TIOCM(int msr)
 205{
 206        int tiocm = 0;
 207
 208        if (msr & UART_MSR_DCD)
 209                tiocm |= TIOCM_CAR;
 210        if (msr & UART_MSR_RI)
 211                tiocm |= TIOCM_RNG;
 212        if (msr & UART_MSR_DSR)
 213                tiocm |= TIOCM_DSR;
 214        if (msr & UART_MSR_CTS)
 215                tiocm |= TIOCM_CTS;
 216
 217        return tiocm;
 218}
 219
 220static inline void serial8250_out_MCR(struct uart_8250_port *up, int value)
 221{
 222        serial_out(up, UART_MCR, value);
 223
 224        if (up->gpios)
 225                mctrl_gpio_set(up->gpios, serial8250_MCR_to_TIOCM(value));
 226}
 227
 228static inline int serial8250_in_MCR(struct uart_8250_port *up)
 229{
 230        int mctrl;
 231
 232        mctrl = serial_in(up, UART_MCR);
 233
 234        if (up->gpios) {
 235                unsigned int mctrl_gpio = 0;
 236
 237                mctrl_gpio = mctrl_gpio_get_outputs(up->gpios, &mctrl_gpio);
 238                mctrl |= serial8250_TIOCM_to_MCR(mctrl_gpio);
 239        }
 240
 241        return mctrl;
 242}
 243
 244#if defined(__alpha__) && !defined(CONFIG_PCI)
 245/*
 246 * Digital did something really horribly wrong with the OUT1 and OUT2
 247 * lines on at least some ALPHA's.  The failure mode is that if either
 248 * is cleared, the machine locks up with endless interrupts.
 249 */
 250#define ALPHA_KLUDGE_MCR  (UART_MCR_OUT2 | UART_MCR_OUT1)
 251#else
 252#define ALPHA_KLUDGE_MCR 0
 253#endif
 254
 255#ifdef CONFIG_SERIAL_8250_PNP
 256int serial8250_pnp_init(void);
 257void serial8250_pnp_exit(void);
 258#else
 259static inline int serial8250_pnp_init(void) { return 0; }
 260static inline void serial8250_pnp_exit(void) { }
 261#endif
 262
 263#ifdef CONFIG_SERIAL_8250_FINTEK
 264int fintek_8250_probe(struct uart_8250_port *uart);
 265#else
 266static inline int fintek_8250_probe(struct uart_8250_port *uart) { return 0; }
 267#endif
 268
 269#ifdef CONFIG_ARCH_OMAP1
 270static inline int is_omap1_8250(struct uart_8250_port *pt)
 271{
 272        int res;
 273
 274        switch (pt->port.mapbase) {
 275        case OMAP1_UART1_BASE:
 276        case OMAP1_UART2_BASE:
 277        case OMAP1_UART3_BASE:
 278                res = 1;
 279                break;
 280        default:
 281                res = 0;
 282                break;
 283        }
 284
 285        return res;
 286}
 287
 288static inline int is_omap1510_8250(struct uart_8250_port *pt)
 289{
 290        if (!cpu_is_omap1510())
 291                return 0;
 292
 293        return is_omap1_8250(pt);
 294}
 295#else
 296static inline int is_omap1_8250(struct uart_8250_port *pt)
 297{
 298        return 0;
 299}
 300static inline int is_omap1510_8250(struct uart_8250_port *pt)
 301{
 302        return 0;
 303}
 304#endif
 305
 306#ifdef CONFIG_SERIAL_8250_DMA
 307extern int serial8250_tx_dma(struct uart_8250_port *);
 308extern int serial8250_rx_dma(struct uart_8250_port *);
 309extern void serial8250_rx_dma_flush(struct uart_8250_port *);
 310extern int serial8250_request_dma(struct uart_8250_port *);
 311extern void serial8250_release_dma(struct uart_8250_port *);
 312#else
 313static inline int serial8250_tx_dma(struct uart_8250_port *p)
 314{
 315        return -1;
 316}
 317static inline int serial8250_rx_dma(struct uart_8250_port *p)
 318{
 319        return -1;
 320}
 321static inline void serial8250_rx_dma_flush(struct uart_8250_port *p) { }
 322static inline int serial8250_request_dma(struct uart_8250_port *p)
 323{
 324        return -1;
 325}
 326static inline void serial8250_release_dma(struct uart_8250_port *p) { }
 327#endif
 328
 329static inline int ns16550a_goto_highspeed(struct uart_8250_port *up)
 330{
 331        unsigned char status;
 332
 333        status = serial_in(up, 0x04); /* EXCR2 */
 334#define PRESL(x) ((x) & 0x30)
 335        if (PRESL(status) == 0x10) {
 336                /* already in high speed mode */
 337                return 0;
 338        } else {
 339                status &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */
 340                status |= 0x10;  /* 1.625 divisor for baud_base --> 921600 */
 341                serial_out(up, 0x04, status);
 342        }
 343        return 1;
 344}
 345
 346static inline int serial_index(struct uart_port *port)
 347{
 348        return port->minor - 64;
 349}
 350