From c495cdae5926c9245d7c943c72a97206d4a0e22a Mon Sep 17 00:00:00 2001 From: Barry Wardell Date: Sun, 11 Nov 2007 16:00:33 +0000 Subject: FS#8046: H10 FM tuner support. Thanks to Przemyslaw Holubowski for doing the hard work in figuring out how to communicate with the tuner. git-svn-id: svn://svn.rockbox.org/rockbox/trunk@15578 a1c6a512-1295-4272-9138-f99709370657 --- firmware/target/arm/iriver/h10/fmradio_i2c-h10.c | 206 +++++++++++++++++++++++ 1 file changed, 206 insertions(+) create mode 100644 firmware/target/arm/iriver/h10/fmradio_i2c-h10.c (limited to 'firmware/target/arm/iriver/h10/fmradio_i2c-h10.c') diff --git a/firmware/target/arm/iriver/h10/fmradio_i2c-h10.c b/firmware/target/arm/iriver/h10/fmradio_i2c-h10.c new file mode 100644 index 0000000000..f3d3075df9 --- /dev/null +++ b/firmware/target/arm/iriver/h10/fmradio_i2c-h10.c @@ -0,0 +1,206 @@ +/*************************************************************************** + * __________ __ ___. + * Open \______ \ ____ ____ | | _\_ |__ _______ ___ + * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / + * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < + * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ + * \/ \/ \/ \/ \/ + * $Id$ + * Physical interface of the Philips TEA5767 in iriver H10 series + * + * Copyright (C) 2002 by Linus Nielsen Feltzing + * + * All files in this archive are subject to the GNU General Public License. + * See the file COPYING in the source tree root for full license agreement. + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY + * KIND, either express or implied. + * + ****************************************************************************/ +#include "config.h" +#include "cpu.h" +#include "logf.h" +#include "system.h" + +/* cute little functions, atomic read-modify-write */ + +#define SDA_OUTINIT GPIO_CLEAR_BITWISE(GPIOD_OUTPUT_VAL, 0x08) +#define SDA_HI_IN GPIO_CLEAR_BITWISE(GPIOD_OUTPUT_EN, 0x08) +#define SDA_LO_OUT GPIO_SET_BITWISE(GPIOD_OUTPUT_EN, 0x08) +#define SDA (GPIOD_INPUT_VAL & 0x08) + +#define SCL_INPUT GPIO_CLEAR_BITWISE(GPIOD_OUTPUT_EN, 0x10) +#define SCL_OUTPUT GPIO_SET_BITWISE(GPIOD_OUTPUT_EN, 0x10) +#define SCL_LO GPIO_CLEAR_BITWISE(GPIOD_OUTPUT_VAL, 0x10) +#define SCL_HI GPIO_SET_BITWISE(GPIOD_OUTPUT_VAL,0x10) +#define SCL (GPIOD_INPUT_VAL & 0x10) + +#define DELAY udelay(2) + +static void fmradio_i2c_start(void) +{ + SCL_HI; + SCL_OUTPUT; + SDA_HI_IN; + SDA_OUTINIT; + DELAY; + SDA_LO_OUT; + DELAY; + SCL_LO; +} + +static void fmradio_i2c_stop(void) +{ + SDA_LO_OUT; + DELAY; + SCL_HI; + DELAY; + SDA_HI_IN; +} + +/* Generate ACK or NACK */ +static void fmradio_i2c_ack(bool nack) +{ + /* Here's the deal. The slave is slow, and sometimes needs to wait + before it can receive the acknowledge. Therefore it forces the clock + low until it is ready. We need to poll the clock line until it goes + high before we release the ack. + + In their infinite wisdom, iriver didn't pull up the SCL line, so + we have to drive the SCL high repeatedly to simulate a pullup. */ + + if (nack) + SDA_HI_IN; + else + SDA_LO_OUT; + DELAY; + + SCL_HI; + do + { + SCL_OUTPUT; /* Set the clock to output */ + SCL_INPUT; /* Set the clock to input */ + DELAY; + } + while(!SCL); /* and wait for the slave to release it */ + + SCL_OUTPUT; + SCL_LO; +} + +static int fmradio_i2c_getack(void) +{ + int ret = 1; + + /* Here's the deal. The slave is slow, and sometimes needs to wait + before it can send the acknowledge. Therefore it forces the clock + low until it is ready. We need to poll the clock line until it goes + high before we read the ack. + + In their infinite wisdom, iriver didn't pull up the SCL line, so + we have to drive the SCL high repeatedly to simulate a pullup. */ + + SDA_HI_IN; + DELAY; + + SCL_HI; /* set clock to high */ + do + { + SCL_OUTPUT; /* Set the clock to output */ + SCL_INPUT; /* Set the clock to input */ + DELAY; + } + while(!SCL); /* and wait for the slave to release it */ + + if (SDA) + ret = 0; /* ack failed */ + + SCL_OUTPUT; + SCL_LO; + + return ret; +} + +static void fmradio_i2c_outb(unsigned char byte) +{ + int i; + + /* clock out each bit, MSB first */ + for ( i=0x80; i; i>>=1 ) { + if ( i & byte ) + SDA_HI_IN; + else + SDA_LO_OUT; + DELAY; + SCL_HI; + DELAY; + SCL_LO; + } +} + +static unsigned char fmradio_i2c_inb(void) +{ + int i; + unsigned char byte = 0; + + SDA_HI_IN; + /* clock in each bit, MSB first */ + for ( i=0x80; i; i>>=1 ) { + DELAY; + SCL_HI; + DELAY; + if ( SDA ) + byte |= i; + SCL_LO; + } + + return byte; +} + +int fmradio_i2c_write(int address, const unsigned char* buf, int count) +{ + int i,x=0; + + fmradio_i2c_start(); + fmradio_i2c_outb(address & 0xfe); + if (fmradio_i2c_getack()) + { + for (i=0; i0; i--) + { + *buf++ = fmradio_i2c_inb(); + fmradio_i2c_ack(i == 1); + } + } + else + x=-1; + fmradio_i2c_stop(); + return x; +} -- cgit v1.2.3