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 struct uart_8250_dma {
  15         int (*tx_dma)(struct uart_8250_port *p);
  16         int (*rx_dma)(struct uart_8250_port *p);
  17
  18         /* Filter function */
  19         dma_filter_fn           fn;
  20         /* Parameter to the filter function */
  21         void                    *rx_param;
  22         void                    *tx_param;
  23
  24         struct dma_slave_config rxconf;
  25         struct dma_slave_config txconf;
  26
  27         struct dma_chan         *rxchan;
  28         struct dma_chan         *txchan;
  29
  30         /* Device address base for DMA operations */
  31         phys_addr_t             rx_dma_addr;
  32         phys_addr_t             tx_dma_addr;
  33
  34         /* DMA address of the buffer in memory */
  35         dma_addr_t              rx_addr;
  36         dma_addr_t              tx_addr;
  37
  38         dma_cookie_t            rx_cookie;
  39         dma_cookie_t            tx_cookie;
  40
  41         void                    *rx_buf;
  42
  43         size_t                  rx_size;
  44         size_t                  tx_size;
  45
  46         unsigned char           tx_running;
  47         unsigned char           tx_err;
  48         unsigned char           rx_running;
  49 };
  50
  51 struct old_serial_port {
  52         unsigned int uart;
  53         unsigned int baud_base;
  54         unsigned int port;
  55         unsigned int irq;
  56         upf_t        flags;
  57         unsigned char io_type;
  58         unsigned char __iomem *iomem_base;
  59         unsigned short iomem_reg_shift;
  60 };
  61
  62 struct serial8250_config {
  63         const char      *name;
  64         unsigned short  fifo_size;
  65         unsigned short  tx_loadsz;
  66         unsigned char   fcr;
  67         unsigned char   rxtrig_bytes[UART_FCR_R_TRIG_MAX_STATE];
  68         unsigned int    flags;
  69 };
  70
  71 #define UART_CAP_FIFO   (1 << 8)        /* UART has FIFO */
  72 #define UART_CAP_EFR    (1 << 9)        /* UART has EFR */
  73 #define UART_CAP_SLEEP  (1 << 10)       /* UART has IER sleep */
  74 #define UART_CAP_AFE    (1 << 11)       /* MCR-based hw flow control */
  75 #define UART_CAP_UUE    (1 << 12)       /* UART needs IER bit 6 set (Xscale) */
  76 #define UART_CAP_RTOIE  (1 << 13)       /* UART needs IER bit 4 set (Xscale, Tegra) */
  77 #define UART_CAP_HFIFO  (1 << 14)       /* UART has a "hidden" FIFO */
  78 #define UART_CAP_RPM    (1 << 15)       /* Runtime PM is active while idle */
  79 #define UART_CAP_IRDA   (1 << 16)       /* UART supports IrDA line discipline */
  80 #define UART_CAP_MINI   (1 << 17)       /* Mini UART on BCM283X family lacks:
  81                                          * STOP PARITY EPAR SPAR WLEN5 WLEN6
  82                                          */
  83
  84 #define UART_BUG_QUOT   (1 << 0)        /* UART has buggy quot LSB */
  85 #define UART_BUG_TXEN   (1 << 1)        /* UART has buggy TX IIR status */
  86 #define UART_BUG_NOMSR  (1 << 2)        /* UART has buggy MSR status bits (Au1x00) */
  87 #define UART_BUG_THRE   (1 << 3)        /* UART has buggy THRE reassertion */
  88 #define UART_BUG_PARITY (1 << 4)        /* UART mishandles parity if FIFO enabled */
  89
  90
  91 #ifdef CONFIG_SERIAL_8250_SHARE_IRQ
  92 #define SERIAL8250_SHARE_IRQS 1
  93 #else
  94 #define SERIAL8250_SHARE_IRQS 0
  95 #endif
  96
  97 #define SERIAL8250_PORT_FLAGS(_base, _irq, _flags)              \
  98         {                                                       \
  99                 .iobase         = _base,                        \
 100                 .irq            = _irq,                         \
 101                 .uartclk        = 1843200,                      \
 102                 .iotype         = UPIO_PORT,                    \
 103                 .flags          = UPF_BOOT_AUTOCONF | (_flags), \
 104         }
 105
 106 #define SERIAL8250_PORT(_base, _irq) SERIAL8250_PORT_FLAGS(_base, _irq, 0)
 107
 108
 109 static inline int serial_in(struct uart_8250_port *up, int offset)
 110 {
 111         return up->port.serial_in(&up->port, offset);
 112 }
 113
 114 static inline void serial_out(struct uart_8250_port *up, int offset, int value)
 115 {
 116         up->port.serial_out(&up->port, offset, value);
 117 }
 118
 119 void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p);
 120
 121 static inline int serial_dl_read(struct uart_8250_port *up)
 122 {
 123         return up->dl_read(up);
 124 }
 125
 126 static inline void serial_dl_write(struct uart_8250_port *up, int value)
 127 {
 128         up->dl_write(up, value);
 129 }
 130
 131 struct uart_8250_port *serial8250_get_port(int line);
 132
 133 void serial8250_rpm_get(struct uart_8250_port *p);
 134 void serial8250_rpm_put(struct uart_8250_port *p);
 135
 136 void serial8250_rpm_get_tx(struct uart_8250_port *p);
 137 void serial8250_rpm_put_tx(struct uart_8250_port *p);
 138
 139 int serial8250_em485_init(struct uart_8250_port *p);
 140 void serial8250_em485_destroy(struct uart_8250_port *p);
 141
 142 static inline void serial8250_out_MCR(struct uart_8250_port *up, int value)
 143 {
 144         serial_out(up, UART_MCR, value);
 145 }
 146
 147 static inline int serial8250_in_MCR(struct uart_8250_port *up)
 148 {
 149         return serial_in(up, UART_MCR);
 150 }
 151
 152 #if defined(__alpha__) && !defined(CONFIG_PCI)
 153 /*
 154  * Digital did something really horribly wrong with the OUT1 and OUT2
 155  * lines on at least some ALPHA's.  The failure mode is that if either
 156  * is cleared, the machine locks up with endless interrupts.
 157  */
 158 #define ALPHA_KLUDGE_MCR  (UART_MCR_OUT2 | UART_MCR_OUT1)
 159 #else
 160 #define ALPHA_KLUDGE_MCR 0
 161 #endif
 162
 163 #ifdef CONFIG_SERIAL_8250_PNP
 164 int serial8250_pnp_init(void);
 165 void serial8250_pnp_exit(void);
 166 #else
 167 static inline int serial8250_pnp_init(void) { return 0; }
 168 static inline void serial8250_pnp_exit(void) { }
 169 #endif
 170
 171 #ifdef CONFIG_SERIAL_8250_FINTEK
 172 int fintek_8250_probe(struct uart_8250_port *uart);
 173 #else
 174 static inline int fintek_8250_probe(struct uart_8250_port *uart) { return 0; }
 175 #endif
 176
 177 #ifdef CONFIG_ARCH_OMAP1
 178 static inline int is_omap1_8250(struct uart_8250_port *pt)
 179 {
 180         int res;
 181
 182         switch (pt->port.mapbase) {
 183         case OMAP1_UART1_BASE:
 184         case OMAP1_UART2_BASE:
 185         case OMAP1_UART3_BASE:
 186                 res = 1;
 187                 break;
 188         default:
 189                 res = 0;
 190                 break;
 191         }
 192
 193         return res;
 194 }
 195
 196 static inline int is_omap1510_8250(struct uart_8250_port *pt)
 197 {
 198         if (!cpu_is_omap1510())
 199                 return 0;
 200
 201         return is_omap1_8250(pt);
 202 }
 203 #else
 204 static inline int is_omap1_8250(struct uart_8250_port *pt)
 205 {
 206         return 0;
 207 }
 208 static inline int is_omap1510_8250(struct uart_8250_port *pt)
 209 {
 210         return 0;
 211 }
 212 #endif
 213
 214 #ifdef CONFIG_SERIAL_8250_DMA
 215 extern int serial8250_tx_dma(struct uart_8250_port *);
 216 extern int serial8250_rx_dma(struct uart_8250_port *);
 217 extern void serial8250_rx_dma_flush(struct uart_8250_port *);
 218 extern int serial8250_request_dma(struct uart_8250_port *);
 219 extern void serial8250_release_dma(struct uart_8250_port *);
 220 #else
 221 static inline int serial8250_tx_dma(struct uart_8250_port *p)
 222 {
 223         return -1;
 224 }
 225 static inline int serial8250_rx_dma(struct uart_8250_port *p)
 226 {
 227         return -1;
 228 }
 229 static inline void serial8250_rx_dma_flush(struct uart_8250_port *p) { }
 230 static inline int serial8250_request_dma(struct uart_8250_port *p)
 231 {
 232         return -1;
 233 }
 234 static inline void serial8250_release_dma(struct uart_8250_port *p) { }
 235 #endif
 236
 237 static inline int ns16550a_goto_highspeed(struct uart_8250_port *up)
 238 {
 239         unsigned char status;
 240
 241         status = serial_in(up, 0x04); /* EXCR2 */
 242 #define PRESL(x) ((x) & 0x30)
 243         if (PRESL(status) == 0x10) {
 244                 /* already in high speed mode */
 245                 return 0;
 246         } else {
 247                 status &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */
 248                 status |= 0x10;  /* 1.625 divisor for baud_base --> 921600 */
 249                 serial_out(up, 0x04, status);
 250         }
 251         return 1;
 252 }
 253
 254 static inline int serial_index(struct uart_port *port)
 255 {
 256         return port->minor - 64;
 257 }