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 85 #define UART_BUG_QUOT (1 << 0) /* UART has buggy quot LSB */ 86 #define UART_BUG_TXEN (1 << 1) /* UART has buggy TX IIR status */ 87 #define UART_BUG_NOMSR (1 << 2) /* UART has buggy MSR status bits (Au1x00) */ 88 #define UART_BUG_THRE (1 << 3) /* UART has buggy THRE reassertion */ 89 #define UART_BUG_PARITY (1 << 4) /* UART mishandles parity if FIFO enabled */ 90 91 92 #ifdef CONFIG_SERIAL_8250_SHARE_IRQ 93 #define SERIAL8250_SHARE_IRQS 1 94 #else 95 #define SERIAL8250_SHARE_IRQS 0 96 #endif 97 98 #define SERIAL8250_PORT_FLAGS(_base, _irq, _flags) \ 99 { \ 100 .iobase = _base, \ 101 .irq = _irq, \ 102 .uartclk = 1843200, \ 103 .iotype = UPIO_PORT, \ 104 .flags = UPF_BOOT_AUTOCONF | (_flags), \ 105 } 106 107 #define SERIAL8250_PORT(_base, _irq) SERIAL8250_PORT_FLAGS(_base, _irq, 0) 108 109 110 static inline int serial_in(struct uart_8250_port *up, int offset) 111 { 112 return up->port.serial_in(&up->port, offset); 113 } 114 115 static inline void serial_out(struct uart_8250_port *up, int offset, int value) 116 { 117 up->port.serial_out(&up->port, offset, value); 118 } 119 120 void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p); 121 122 static inline int serial_dl_read(struct uart_8250_port *up) 123 { 124 return up->dl_read(up); 125 } 126 127 static inline void serial_dl_write(struct uart_8250_port *up, int value) 128 { 129 up->dl_write(up, value); 130 } 131 132 struct uart_8250_port *serial8250_get_port(int line); 133 134 void serial8250_rpm_get(struct uart_8250_port *p); 135 void serial8250_rpm_put(struct uart_8250_port *p); 136 137 void serial8250_rpm_get_tx(struct uart_8250_port *p); 138 void serial8250_rpm_put_tx(struct uart_8250_port *p); 139 140 int serial8250_em485_init(struct uart_8250_port *p); 141 void serial8250_em485_destroy(struct uart_8250_port *p); 142 143 static inline void serial8250_out_MCR(struct uart_8250_port *up, int value) 144 { 145 serial_out(up, UART_MCR, value); 146 } 147 148 static inline int serial8250_in_MCR(struct uart_8250_port *up) 149 { 150 return serial_in(up, UART_MCR); 151 } 152 153 #if defined(__alpha__) && !defined(CONFIG_PCI) 154 /* 155 * Digital did something really horribly wrong with the OUT1 and OUT2 156 * lines on at least some ALPHA's. The failure mode is that if either 157 * is cleared, the machine locks up with endless interrupts. 158 */ 159 #define ALPHA_KLUDGE_MCR (UART_MCR_OUT2 | UART_MCR_OUT1) 160 #else 161 #define ALPHA_KLUDGE_MCR 0 162 #endif 163 164 #ifdef CONFIG_SERIAL_8250_PNP 165 int serial8250_pnp_init(void); 166 void serial8250_pnp_exit(void); 167 #else 168 static inline int serial8250_pnp_init(void) { return 0; } 169 static inline void serial8250_pnp_exit(void) { } 170 #endif 171 172 #ifdef CONFIG_SERIAL_8250_FINTEK 173 int fintek_8250_probe(struct uart_8250_port *uart); 174 #else 175 static inline int fintek_8250_probe(struct uart_8250_port *uart) { return 0; } 176 #endif 177 178 #ifdef CONFIG_ARCH_OMAP1 179 static inline int is_omap1_8250(struct uart_8250_port *pt) 180 { 181 int res; 182 183 switch (pt->port.mapbase) { 184 case OMAP1_UART1_BASE: 185 case OMAP1_UART2_BASE: 186 case OMAP1_UART3_BASE: 187 res = 1; 188 break; 189 default: 190 res = 0; 191 break; 192 } 193 194 return res; 195 } 196 197 static inline int is_omap1510_8250(struct uart_8250_port *pt) 198 { 199 if (!cpu_is_omap1510()) 200 return 0; 201 202 return is_omap1_8250(pt); 203 } 204 #else 205 static inline int is_omap1_8250(struct uart_8250_port *pt) 206 { 207 return 0; 208 } 209 static inline int is_omap1510_8250(struct uart_8250_port *pt) 210 { 211 return 0; 212 } 213 #endif 214 215 #ifdef CONFIG_SERIAL_8250_DMA 216 extern int serial8250_tx_dma(struct uart_8250_port *); 217 extern int serial8250_rx_dma(struct uart_8250_port *); 218 extern void serial8250_rx_dma_flush(struct uart_8250_port *); 219 extern int serial8250_request_dma(struct uart_8250_port *); 220 extern void serial8250_release_dma(struct uart_8250_port *); 221 #else 222 static inline int serial8250_tx_dma(struct uart_8250_port *p) 223 { 224 return -1; 225 } 226 static inline int serial8250_rx_dma(struct uart_8250_port *p) 227 { 228 return -1; 229 } 230 static inline void serial8250_rx_dma_flush(struct uart_8250_port *p) { } 231 static inline int serial8250_request_dma(struct uart_8250_port *p) 232 { 233 return -1; 234 } 235 static inline void serial8250_release_dma(struct uart_8250_port *p) { } 236 #endif 237 238 static inline int ns16550a_goto_highspeed(struct uart_8250_port *up) 239 { 240 unsigned char status; 241 242 status = serial_in(up, 0x04); /* EXCR2 */ 243 #define PRESL(x) ((x) & 0x30) 244 if (PRESL(status) == 0x10) { 245 /* already in high speed mode */ 246 return 0; 247 } else { 248 status &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */ 249 status |= 0x10; /* 1.625 divisor for baud_base --> 921600 */ 250 serial_out(up, 0x04, status); 251 } 252 return 1; 253 } 254 255 static inline int serial_index(struct uart_port *port) 256 { 257 return port->minor - 64; 258 } 259