Nyaaori/rockbox
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

Apply FS #11423 - Use udelay in AMS driver for FM radio I2C

Browse source 
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@27035 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Bertrik Sikken 2010-06-21 21:41:07 +00:00
parent 06b9064205
commit 2062270964
3 changed files with 105 additions and 121 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

92
firmware/drivers/generic_i2c.c
View file

@ -32,55 +32,51 @@ static const struct i2c_interface *i2c_if[MAX_I2C_INTERFACES];
static void i2c_start(const struct i2c_interface *iface)
{
iface->sda_output();
iface->sda_dir(true);
iface->sda_hi();
iface->scl_hi();
iface->delay_su_sta();
iface->sda_lo();
iface->delay_hd_sta();
iface->scl_lo();
iface->delay_hd_dat();
iface->sda_out(1);
iface->scl_out(1);
iface->delay(iface->delay_su_sta);
iface->sda_out(0);
iface->delay(iface->delay_hd_sta);
iface->scl_out(0);
iface->delay(iface->delay_hd_dat);
}
static void i2c_stop(const struct i2c_interface *iface)
{
iface->sda_output();
iface->sda_dir(true);
iface->sda_lo();
iface->delay_su_dat();
iface->scl_hi();
iface->delay_su_sto();
iface->sda_hi();
iface->sda_out(0);
iface->delay(iface->delay_su_dat);
iface->scl_out(1);
iface->delay(iface->delay_su_sto);
iface->sda_out(1);
}
static void i2c_ack(const struct i2c_interface *iface, bool ack)
{
iface->sda_output();
if ( ack )
iface->sda_lo();
else
iface->sda_hi();
iface->delay_su_dat();
iface->scl_hi();
iface->delay_thigh();
iface->scl_lo();
iface->delay_hd_dat();
iface->sda_dir(true);
iface->sda_out(!ack);
iface->delay(iface->delay_su_dat);
iface->scl_out(1);
iface->delay(iface->delay_thigh);
iface->scl_out(0);
iface->delay(iface->delay_hd_dat);
}
static int i2c_getack(const struct i2c_interface *iface)
{
int ret = 1;
iface->sda_input();
iface->delay_su_dat();
iface->scl_hi();
iface->delay_thigh();
if (iface->sda())
iface->sda_dir(false);
iface->delay(iface->delay_su_dat);
iface->scl_out(1);
iface->delay(iface->delay_thigh);
if (iface->sda_in())
ret = 0; /* ack failed */
iface->scl_lo();
iface->delay_hd_dat();
iface->scl_out(0);
iface->delay(iface->delay_hd_dat);
return ret;
}
@ -89,17 +85,17 @@ static unsigned char i2c_inb(const struct i2c_interface *iface, bool ack)
int i;
unsigned char byte = 0;
iface->sda_input();
iface->sda_dir(false);
/* clock in each bit, MSB first */
for ( i=0x80; i; i>>=1 ) {
iface->delay_su_dat();
iface->scl_hi();
iface->delay_thigh();
if (iface->sda())
iface->delay(iface->delay_su_dat);
iface->scl_out(1);
iface->delay(iface->delay_thigh);
if (iface->sda_in())
byte |= i;
iface->scl_lo();
iface->delay_hd_dat();
iface->scl_out(0);
iface->delay(iface->delay_hd_dat);
}
i2c_ack(iface, ack);
@ -111,18 +107,16 @@ static int i2c_outb(const struct i2c_interface *iface, unsigned char byte)
{
int i;
iface->sda_output();
iface->sda_dir(true);
/* clock out each bit, MSB first */
for (i=0x80; i; i>>=1) {
if (i & byte)
iface->sda_hi();
else
iface->sda_lo();
iface->delay_su_dat();
iface->scl_hi();
iface->delay_thigh();
iface->scl_lo();
iface->sda_out(i & byte);
iface->delay(iface->delay_su_dat);
iface->scl_out(1);
iface->delay(iface->delay_thigh);
iface->scl_out(0);
iface->delay(iface->delay_hd_dat);
}
return i2c_getack(iface);
@ -215,7 +209,7 @@ int i2c_add_node(const struct i2c_interface *iface)
bus_index = i2c_num_ifs++;
i2c_if[bus_index] = iface;
iface->scl_output();
iface->scl_dir(true);
return bus_index;
}

33
firmware/export/generic_i2c.h
View file

@ -21,27 +21,26 @@
#ifndef _GEN_I2C_
#define _GEN_I2C_
#include <stdbool.h>
struct i2c_interface
{
void (*scl_hi)(void); /* Drive SCL high, might sleep on clk stretch */
void (*scl_lo)(void); /* Drive SCL low */
void (*sda_hi)(void); /* Drive SDA high */
void (*sda_lo)(void); /* Drive SDA low */
void (*sda_input)(void); /* Set SDA as input */
void (*sda_output)(void); /* Set SDA as output */
void (*scl_input)(void); /* Set SCL as input */
void (*scl_output)(void); /* Set SCL as output */
int (*scl)(void); /* Read SCL, returns 0 or non-zero */
int (*sda)(void); /* Read SDA, returns 0 or non-zero */
void (*scl_dir)(bool out); /* Set SCL as input or output */
void (*sda_dir)(bool out); /* Set SDA as input or output */
void (*scl_out)(bool high); /* Drive SCL, might sleep on clk stretch */
void (*sda_out)(bool high); /* Drive SDA */
bool (*scl_in)(void); /* Read SCL, returns true if high */
bool (*sda_in)(void); /* Read SDA, returns true if high */
void (*delay)(int delay); /* Delay for the specified amount */
/* These are the delays specified in the I2C specification, the
time pairs to the right are the minimum 100kHz and 400kHz specs */
void (*delay_hd_sta)(void); /* START SDA hold (tHD:SDA) 4.0us/0.6us */
void (*delay_hd_dat)(void); /* SDA hold (tHD:DAT) 5.0us/0us */
void (*delay_su_dat)(void); /* SDA setup (tSU:DAT) 250ns/100ns */
void (*delay_su_sto)(void); /* STOP setup (tSU:STO) 4.0us/0.6us */
void (*delay_su_sta)(void); /* Rep. START setup (tSU:STA) 4.7us/0.6us */
void (*delay_thigh)(void); /* SCL high period (tHIGH) 4.0us/0.6us */
int delay_hd_sta; /* START SDA hold (tHD:SDA) 4.0us/0.6us */
int delay_hd_dat; /* SDA hold (tHD:DAT) 5.0us/0us */
int delay_su_dat; /* SDA setup (tSU:DAT) 250ns/100ns */
int delay_su_sto; /* STOP setup (tSU:STO) 4.0us/0.6us */
int delay_su_sta; /* Rep. START setup (tSU:STA) 4.7us/0.6us */
int delay_thigh; /* SCL high period (tHIGH) 4.0us/0.6us */
};
int i2c_add_node(const struct i2c_interface *iface);

101
firmware/target/arm/as3525/fmradio-i2c-as3525.c
View file

@ -28,6 +28,7 @@
*/
#include "as3525.h"
#include "system.h"
#include "generic_i2c.h"
#include "fmradio_i2c.h"
@ -77,85 +78,75 @@
static int fm_i2c_bus;
static void fm_scl_hi(void)
static void fm_scl_dir(bool out)
{
I2C_SCL_GPIO(I2C_SCL_PIN) = 1 << I2C_SCL_PIN;
if (out) {
I2C_SCL_GPIO_DIR |= 1 << I2C_SCL_PIN;
} else {
I2C_SCL_GPIO_DIR &= ~(1 << I2C_SCL_PIN);
}
}
static void fm_scl_lo(void)
static void fm_sda_dir(bool out)
{
I2C_SCL_GPIO(I2C_SCL_PIN) = 0;
if (out) {
I2C_SDA_GPIO_DIR |= 1 << I2C_SDA_PIN;
} else {
I2C_SDA_GPIO_DIR &= ~(1 << I2C_SDA_PIN);
}
}
static void fm_sda_hi(void)
static void fm_scl_out(bool level)
{
I2C_SDA_GPIO(I2C_SDA_PIN) = 1 << I2C_SDA_PIN;
if (level) {
I2C_SCL_GPIO(I2C_SCL_PIN) = 1 << I2C_SCL_PIN;
} else {
I2C_SCL_GPIO(I2C_SCL_PIN) = 0;
}
}
static void fm_sda_lo(void)
static void fm_sda_out(bool level)
{
I2C_SDA_GPIO(I2C_SDA_PIN) = 0;
if (level) {
I2C_SDA_GPIO(I2C_SDA_PIN) = 1 << I2C_SDA_PIN;
} else {
I2C_SDA_GPIO(I2C_SDA_PIN) = 0;
}
}
static void fm_sda_input(void)
{
I2C_SDA_GPIO_DIR &= ~(1 << I2C_SDA_PIN);
}
static void fm_sda_output(void)
{
I2C_SDA_GPIO_DIR |= 1 << I2C_SDA_PIN;
}
static void fm_scl_input(void)
{
I2C_SCL_GPIO_DIR &= ~(1 << I2C_SCL_PIN);
}
static void fm_scl_output(void)
{
I2C_SCL_GPIO_DIR |= 1 << I2C_SCL_PIN;
}
static int fm_sda(void)
{
return I2C_SDA_GPIO(I2C_SDA_PIN);
}
static int fm_scl(void)
static bool fm_scl_in(void)
{
return I2C_SCL_GPIO(I2C_SCL_PIN);
}
/* simple and crude delay, used for all delays in the generic i2c driver */
static void fm_delay(void)
static bool fm_sda_in(void)
{
volatile int i;
return I2C_SDA_GPIO(I2C_SDA_PIN);
}
/* this loop is uncalibrated and could use more sophistication */
for (i = 0; i < 20; i++) {
static void fm_delay(int delay)
{
if (delay != 0) {
udelay(delay);
}
}
/* interface towards the generic i2c driver */
static const struct i2c_interface fm_i2c_interface = {
.scl_hi = fm_scl_hi,
.scl_lo = fm_scl_lo,
.sda_hi = fm_sda_hi,
.sda_lo = fm_sda_lo,
.sda_input = fm_sda_input,
.sda_output = fm_sda_output,
.scl_input = fm_scl_input,
.scl_output = fm_scl_output,
.scl = fm_scl,
.sda = fm_sda,
.scl_out = fm_scl_out,
.scl_dir = fm_scl_dir,
.sda_out = fm_sda_out,
.sda_dir = fm_sda_dir,
.sda_in = fm_sda_in,
.scl_in = fm_scl_in,
.delay = fm_delay,
.delay_hd_sta = fm_delay,
.delay_hd_dat = fm_delay,
.delay_su_dat = fm_delay,
.delay_su_sto = fm_delay,
.delay_su_sta = fm_delay,
.delay_thigh = fm_delay
.delay_hd_sta = 1,
.delay_hd_dat = 0,
.delay_su_dat = 1,
.delay_su_sto = 1,
.delay_su_sta = 1,
.delay_thigh = 2
};
/* initialise i2c for fmradio */