diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/Makefile | 1 | ||||
| -rw-r--r-- | drivers/serial_max3100.c | 301 |
2 files changed, 302 insertions, 0 deletions
diff --git a/drivers/Makefile b/drivers/Makefile index 8eb9472..f1ea117 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -37,6 +37,7 @@ OBJS = 3c589.o 5701rls.o ali512x.o \ pci.o pci_auto.o pci_indirect.o \ pcnet.o plb2800_eth.o \ s3c24x0_i2c.o sed13806.o serial.o \ + serial_max3100.o \ smc91111.o smiLynxEM.o sym53c8xx.o \ ti_pci1410a.o tigon3.o w83c553f.o \ status_led.o diff --git a/drivers/serial_max3100.c b/drivers/serial_max3100.c new file mode 100644 index 0000000..bbe212b --- /dev/null +++ b/drivers/serial_max3100.c @@ -0,0 +1,301 @@ +/* + * (C) Copyright 2003 + * + * Pantelis Antoniou <panto@intracom.gr> + * Intracom S.A. + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <common.h> +#include <watchdog.h> + +#ifdef CONFIG_MAX3100_SERIAL + +/**************************************************************/ + +/* convienient macros */ +#define MAX3100_SPI_RXD() (MAX3100_SPI_RXD_PORT & MAX3100_SPI_RXD_BIT) + +#define MAX3100_SPI_TXD(x) \ + do { \ + if (x) \ + MAX3100_SPI_TXD_PORT |= MAX3100_SPI_TXD_BIT; \ + else \ + MAX3100_SPI_TXD_PORT &= ~MAX3100_SPI_TXD_BIT; \ + } while(0) + +#define MAX3100_SPI_CLK(x) \ + do { \ + if (x) \ + MAX3100_SPI_CLK_PORT |= MAX3100_SPI_CLK_BIT; \ + else \ + MAX3100_SPI_CLK_PORT &= ~MAX3100_SPI_CLK_BIT; \ + } while(0) + +#define MAX3100_SPI_CLK_TOGGLE() (MAX3100_SPI_CLK_PORT ^= MAX3100_SPI_CLK_BIT) + +#define MAX3100_CS(x) \ + do { \ + if (x) \ + MAX3100_CS_PORT |= MAX3100_CS_BIT; \ + else \ + MAX3100_CS_PORT &= ~MAX3100_CS_BIT; \ + } while(0) + +/**************************************************************/ + +/* MAX3100 definitions */ + +#define MAX3100_WC (3 << 14) /* write configuration */ +#define MAX3100_RC (1 << 14) /* read configuration */ +#define MAX3100_WD (2 << 14) /* write data */ +#define MAX3100_RD (0 << 14) /* read data */ + +/* configuration register bits */ +#define MAX3100_FEN (1 << 13) /* FIFO enable */ +#define MAX3100_SHDN (1 << 12) /* shutdown bit */ +#define MAX3100_TM (1 << 11) /* T bit irq mask */ +#define MAX3100_RM (1 << 10) /* R bit irq mask */ +#define MAX3100_PM (1 << 9) /* P bit irq mask */ +#define MAX3100_RAM (1 << 8) /* mask for RA/FE bit */ +#define MAX3100_IR (1 << 7) /* IRDA timing mode */ +#define MAX3100_ST (1 << 6) /* transmit stop bit */ +#define MAX3100_PE (1 << 5) /* parity enable bit */ +#define MAX3100_L (1 << 4) /* Length bit */ +#define MAX3100_B_MASK (0x000F) /* baud rate bits mask */ +#define MAX3100_B(x) ((x) & 0x000F) /* baud rate select bits */ + +/* data register bits (write) */ +#define MAX3100_TE (1 << 10) /* transmit enable bit (active low) */ +#define MAX3100_RTS (1 << 9) /* request-to-send bit (inverted ~RTS pin) */ + +/* data register bits (read) */ +#define MAX3100_RA (1 << 10) /* receiver activity when in shutdown mode */ +#define MAX3100_FE (1 << 10) /* framing error when in normal mode */ +#define MAX3100_CTS (1 << 9) /* clear-to-send bit (inverted ~CTS pin) */ + +/* data register bits (both directions) */ +#define MAX3100_R (1 << 15) /* receive bit */ +#define MAX3100_T (1 << 14) /* transmit bit */ +#define MAX3100_P (1 << 8) /* parity bit */ +#define MAX3100_D_MASK 0x00FF /* data bits mask */ +#define MAX3100_D(x) ((x) & 0x00FF) /* data bits */ + +/* these definitions are valid only for fOSC = 3.6864MHz */ +#define MAX3100_B_230400 MAX3100_B(0) +#define MAX3100_B_115200 MAX3100_B(1) +#define MAX3100_B_57600 MAX3100_B(2) +#define MAX3100_B_38400 MAX3100_B(9) +#define MAX3100_B_19200 MAX3100_B(10) +#define MAX3100_B_9600 MAX3100_B(11) +#define MAX3100_B_4800 MAX3100_B(12) +#define MAX3100_B_2400 MAX3100_B(13) +#define MAX3100_B_1200 MAX3100_B(14) +#define MAX3100_B_600 MAX3100_B(15) + +/**************************************************************/ + +static inline unsigned int max3100_transfer(unsigned int val) +{ + unsigned int rx; + int b; + + MAX3100_SPI_CLK(0); + MAX3100_CS(0); + + rx = 0; b = 16; + while (--b >= 0) { + MAX3100_SPI_TXD(val & 0x8000); + val <<= 1; + MAX3100_SPI_CLK_TOGGLE(); + udelay(1); + rx <<= 1; + if (MAX3100_SPI_RXD()) + rx |= 1; + MAX3100_SPI_CLK_TOGGLE(); + udelay(1); + } + + MAX3100_SPI_CLK(1); + MAX3100_CS(1); + + return rx; +} + +/**************************************************************/ + +/* must be power of 2 */ +#define RXFIFO_SZ 16 + +static int rxfifo_cnt; +static int rxfifo_in; +static int rxfifo_out; +static unsigned char rxfifo_buf[16]; + +static void max3100_putc(int c) +{ + unsigned int rx; + + while (((rx = max3100_transfer(MAX3100_RC)) & MAX3100_T) == 0) + WATCHDOG_RESET(); + + rx = max3100_transfer(MAX3100_WD | (c & 0xff)); + if ((rx & MAX3100_RD) != 0 && rxfifo_cnt < RXFIFO_SZ) { + rxfifo_cnt++; + rxfifo_buf[rxfifo_in++] = rx & 0xff; + rxfifo_in &= RXFIFO_SZ - 1; + } +} + +static int max3100_getc(void) +{ + int c; + unsigned int rx; + + while (rxfifo_cnt == 0) { + rx = max3100_transfer(MAX3100_RD); + if ((rx & MAX3100_R) != 0) { + do { + rxfifo_cnt++; + rxfifo_buf[rxfifo_in++] = rx & 0xff; + rxfifo_in &= RXFIFO_SZ - 1; + + if (rxfifo_cnt >= RXFIFO_SZ) + break; + } while (((rx = max3100_transfer(MAX3100_RD)) & MAX3100_R) != 0); + } + WATCHDOG_RESET(); + } + + rxfifo_cnt--; + c = rxfifo_buf[rxfifo_out++]; + rxfifo_out &= RXFIFO_SZ - 1; + return c; +} + +static int max3100_tstc(void) +{ + unsigned int rx; + + if (rxfifo_cnt > 0) + return 1; + + rx = max3100_transfer(MAX3100_RD); + if ((rx & MAX3100_R) == 0) + return 0; + + do { + rxfifo_cnt++; + rxfifo_buf[rxfifo_in++] = rx & 0xff; + rxfifo_in &= RXFIFO_SZ - 1; + + if (rxfifo_cnt >= RXFIFO_SZ) + break; + } while (((rx = max3100_transfer(MAX3100_RD)) & MAX3100_R) != 0); + + return 1; +} + +int serial_init(void) +{ + unsigned int wconf, rconf; + int i; + DECLARE_GLOBAL_DATA_PTR; + + wconf = 0; + + /* Set baud rate */ + switch (gd->baudrate) { + case 1200: + wconf = MAX3100_B_1200; + break; + case 2400: + wconf = MAX3100_B_2400; + break; + case 4800: + wconf = MAX3100_B_4800; + break; + case 9600: + wconf = MAX3100_B_9600; + break; + case 19200: + wconf = MAX3100_B_19200; + break; + case 38400: + wconf = MAX3100_B_38400; + break; + case 57600: + wconf = MAX3100_B_57600; + break; + default: + case 115200: + wconf = MAX3100_B_115200; + break; + case 230400: + wconf = MAX3100_B_230400; + break; + } + + /* try for 10ms, with a 100us gap */ + for (i = 0; i < 10000; i += 100) { + + max3100_transfer(MAX3100_WC | wconf); + rconf = max3100_transfer(MAX3100_RC) & 0x3fff; + + if (rconf == wconf) + break; + udelay(100); + } + + rxfifo_in = rxfifo_out = rxfifo_cnt = 0; + + return (0); +} + +void serial_putc(const char c) +{ + if (c == '\n') + max3100_putc('\r'); + + max3100_putc(c); +} + +void serial_puts(const char *s) +{ + while (*s) + serial_putc (*s++); +} + +int serial_getc(void) +{ + return max3100_getc(); +} + +int serial_tstc(void) +{ + return max3100_tstc(); +} + +/* XXX WTF? */ +void serial_setbrg(void) +{ +} + +#endif |