1 /* 2 * Driver for 8250/16550-type serial ports 3 * 4 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o. 5 * 6 * Copyright (C) 2001 Russell King. 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 */ 13 14 #include <linux/serial_8250.h> 15 #include <linux/serial_reg.h> 16 #include <linux/dmaengine.h> 17 18 struct uart_8250_dma { 19 int (*tx_dma)(struct uart_8250_port *p); 20 int (*rx_dma)(struct uart_8250_port *p); 21 22 /* Filter function */ 23 dma_filter_fn fn; 24 /* Parameter to the filter function */ 25 void *rx_param; 26 void *tx_param; 27 28 struct dma_slave_config rxconf; 29 struct dma_slave_config txconf; 30 31 struct dma_chan *rxchan; 32 struct dma_chan *txchan; 33 34 /* Device address base for DMA operations */ 35 phys_addr_t rx_dma_addr; 36 phys_addr_t tx_dma_addr; 37 38 /* DMA address of the buffer in memory */ 39 dma_addr_t rx_addr; 40 dma_addr_t tx_addr; 41 42 dma_cookie_t rx_cookie; 43 dma_cookie_t tx_cookie; 44 45 void *rx_buf; 46 47 size_t rx_size; 48 size_t tx_size; 49 50 unsigned char tx_running; 51 unsigned char tx_err; 52 unsigned char rx_running; 53 }; 54 55 struct old_serial_port { 56 unsigned int uart; 57 unsigned int baud_base; 58 unsigned int port; 59 unsigned int irq; 60 upf_t flags; 61 unsigned char io_type; 62 unsigned char __iomem *iomem_base; 63 unsigned short iomem_reg_shift; 64 }; 65 66 struct serial8250_config { 67 const char *name; 68 unsigned short fifo_size; 69 unsigned short tx_loadsz; 70 unsigned char fcr; 71 unsigned char rxtrig_bytes[UART_FCR_R_TRIG_MAX_STATE]; 72 unsigned int flags; 73 }; 74 75 #define UART_CAP_FIFO (1 << 8) /* UART has FIFO */ 76 #define UART_CAP_EFR (1 << 9) /* UART has EFR */ 77 #define UART_CAP_SLEEP (1 << 10) /* UART has IER sleep */ 78 #define UART_CAP_AFE (1 << 11) /* MCR-based hw flow control */ 79 #define UART_CAP_UUE (1 << 12) /* UART needs IER bit 6 set (Xscale) */ 80 #define UART_CAP_RTOIE (1 << 13) /* UART needs IER bit 4 set (Xscale, Tegra) */ 81 #define UART_CAP_HFIFO (1 << 14) /* UART has a "hidden" FIFO */ 82 #define UART_CAP_RPM (1 << 15) /* Runtime PM is active while idle */ 83 #define UART_CAP_IRDA (1 << 16) /* UART supports IrDA line discipline */ 84 #define UART_CAP_MINI (1 << 17) /* Mini UART on BCM283X family lacks: 85 * STOP PARITY EPAR SPAR WLEN5 WLEN6 86 */ 87 88 #define UART_BUG_QUOT (1 << 0) /* UART has buggy quot LSB */ 89 #define UART_BUG_TXEN (1 << 1) /* UART has buggy TX IIR status */ 90 #define UART_BUG_NOMSR (1 << 2) /* UART has buggy MSR status bits (Au1x00) */ 91 #define UART_BUG_THRE (1 << 3) /* UART has buggy THRE reassertion */ 92 #define UART_BUG_PARITY (1 << 4) /* UART mishandles parity if FIFO enabled */ 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) 111 112 113 static inline int serial_in(struct uart_8250_port *up, int offset) 114 { 115 return up->port.serial_in(&up->port, offset); 116 } 117 118 static inline void serial_out(struct uart_8250_port *up, int offset, int value) 119 { 120 up->port.serial_out(&up->port, offset, value); 121 } 122 123 void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p); 124 125 static inline int serial_dl_read(struct uart_8250_port *up) 126 { 127 return up->dl_read(up); 128 } 129 130 static inline void serial_dl_write(struct uart_8250_port *up, int value) 131 { 132 up->dl_write(up, value); 133 } 134 135 struct uart_8250_port *serial8250_get_port(int line); 136 137 void serial8250_rpm_get(struct uart_8250_port *p); 138 void serial8250_rpm_put(struct uart_8250_port *p); 139 140 void serial8250_rpm_get_tx(struct uart_8250_port *p); 141 void serial8250_rpm_put_tx(struct uart_8250_port *p); 142 143 int serial8250_em485_init(struct uart_8250_port *p); 144 void serial8250_em485_destroy(struct uart_8250_port *p); 145 146 static inline void serial8250_out_MCR(struct uart_8250_port *up, int value) 147 { 148 serial_out(up, UART_MCR, value); 149 } 150 151 static inline int serial8250_in_MCR(struct uart_8250_port *up) 152 { 153 return serial_in(up, UART_MCR); 154 } 155 156 #if defined(__alpha__) && !defined(CONFIG_PCI) 157 /* 158 * Digital did something really horribly wrong with the OUT1 and OUT2 159 * lines on at least some ALPHA's. The failure mode is that if either 160 * is cleared, the machine locks up with endless interrupts. 161 */ 162 #define ALPHA_KLUDGE_MCR (UART_MCR_OUT2 | UART_MCR_OUT1) 163 #else 164 #define ALPHA_KLUDGE_MCR 0 165 #endif 166 167 #ifdef CONFIG_SERIAL_8250_PNP 168 int serial8250_pnp_init(void); 169 void serial8250_pnp_exit(void); 170 #else 171 static inline int serial8250_pnp_init(void) { return 0; } 172 static inline void serial8250_pnp_exit(void) { } 173 #endif 174 175 #ifdef CONFIG_SERIAL_8250_FINTEK 176 int fintek_8250_probe(struct uart_8250_port *uart); 177 #else 178 static inline int fintek_8250_probe(struct uart_8250_port *uart) { return 0; } 179 #endif 180 181 #ifdef CONFIG_ARCH_OMAP1 182 static inline int is_omap1_8250(struct uart_8250_port *pt) 183 { 184 int res; 185 186 switch (pt->port.mapbase) { 187 case OMAP1_UART1_BASE: 188 case OMAP1_UART2_BASE: 189 case OMAP1_UART3_BASE: 190 res = 1; 191 break; 192 default: 193 res = 0; 194 break; 195 } 196 197 return res; 198 } 199 200 static inline int is_omap1510_8250(struct uart_8250_port *pt) 201 { 202 if (!cpu_is_omap1510()) 203 return 0; 204 205 return is_omap1_8250(pt); 206 } 207 #else 208 static inline int is_omap1_8250(struct uart_8250_port *pt) 209 { 210 return 0; 211 } 212 static inline int is_omap1510_8250(struct uart_8250_port *pt) 213 { 214 return 0; 215 } 216 #endif 217 218 #ifdef CONFIG_SERIAL_8250_DMA 219 extern int serial8250_tx_dma(struct uart_8250_port *); 220 extern int serial8250_rx_dma(struct uart_8250_port *); 221 extern void serial8250_rx_dma_flush(struct uart_8250_port *); 222 extern int serial8250_request_dma(struct uart_8250_port *); 223 extern void serial8250_release_dma(struct uart_8250_port *); 224 #else 225 static inline int serial8250_tx_dma(struct uart_8250_port *p) 226 { 227 return -1; 228 } 229 static inline int serial8250_rx_dma(struct uart_8250_port *p) 230 { 231 return -1; 232 } 233 static inline void serial8250_rx_dma_flush(struct uart_8250_port *p) { } 234 static inline int serial8250_request_dma(struct uart_8250_port *p) 235 { 236 return -1; 237 } 238 static inline void serial8250_release_dma(struct uart_8250_port *p) { } 239 #endif 240 241 static inline int ns16550a_goto_highspeed(struct uart_8250_port *up) 242 { 243 unsigned char status; 244 245 status = serial_in(up, 0x04); /* EXCR2 */ 246 #define PRESL(x) ((x) & 0x30) 247 if (PRESL(status) == 0x10) { 248 /* already in high speed mode */ 249 return 0; 250 } else { 251 status &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */ 252 status |= 0x10; /* 1.625 divisor for baud_base --> 921600 */ 253 serial_out(up, 0x04, status); 254 } 255 return 1; 256 } 257 258 static inline int serial_index(struct uart_port *port) 259 { 260 return port->minor - 64; 261 } 262