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Revert the S5L870X I2C driver to busy waiting because of some issues with interrupts, and increase the bus speed from 24kHz to 390kHz.

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@23074 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Michael Sparmann 2009-10-10 16:36:55 +00:00
parent 72271af7df
commit 6be1d8b8a8
1 changed files with 18 additions and 28 deletions
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46
firmware/target/arm/s5l8700/i2c-s5l8700.c
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@ -40,20 +40,10 @@
*/
static struct mutex i2c_mtx;
static struct wakeup i2c_wakeup;
void INT_IIC(void)
{
/* disable interrupt (but don't clear it yet) */
IICCON &= ~((1 << 4) | (1 << 5));
wakeup_signal(&i2c_wakeup);
}
void i2c_init(void)
{
mutex_init(&i2c_mtx);
wakeup_init(&i2c_wakeup);
/* enable I2C pins */
PCON10 = (2 << 2) |
@ -65,10 +55,10 @@ void i2c_init(void)
/* initial config */
IICADD = 0;
IICCON = (1 << 7) | /* ACK_GEN */
(1 << 6) | /* CLKSEL = PCLK/512 */
(0 << 6) | /* CLKSEL = PCLK/16 */
(1 << 5) | /* INT_EN */
(1 << 4) | /* IRQ clear */
(3 << 0); /* CK_REG */
(7 << 0); /* CK_REG */
/* serial output on */
IICSTAT = (1 << 4);
@ -84,26 +74,26 @@ int i2c_write(unsigned char slave, int address, int len, const unsigned char *da
/* START */
IICDS = slave & ~1;
IICSTAT = 0xF0;
IICCON = 0xF3;
while ((IICCON & 0x10) == 0) wakeup_wait(&i2c_wakeup, 1);
IICCON = 0xB7;
while ((IICCON & 0x10) == 0);
if (address >= 0) {
/* write address */
IICDS = address;
IICCON = 0xF3;
while ((IICCON & 0x10) == 0) wakeup_wait(&i2c_wakeup, 1);
IICCON = 0xB7;
while ((IICCON & 0x10) == 0);
}
/* write data */
while (len--) {
IICDS = *data++;
IICCON = 0xF3;
while ((IICCON & 0x10) == 0) wakeup_wait(&i2c_wakeup, 1);
IICCON = 0xB7;
while ((IICCON & 0x10) == 0);
}
/* STOP */
IICSTAT = 0xD0;
IICCON = 0xF3;
IICCON = 0xB7;
while ((IICSTAT & (1 << 5)) != 0);
mutex_unlock(&i2c_mtx);
@ -118,30 +108,30 @@ int i2c_read(unsigned char slave, int address, int len, unsigned char *data)
/* START */
IICDS = slave & ~1;
IICSTAT = 0xF0;
IICCON = 0xF3;
while ((IICCON & 0x10) == 0) wakeup_wait(&i2c_wakeup, 1);
IICCON = 0xB7;
while ((IICCON & 0x10) == 0);
/* write address */
IICDS = address;
IICCON = 0xF3;
while ((IICCON & 0x10) == 0) wakeup_wait(&i2c_wakeup, 1);
IICCON = 0xB7;
while ((IICCON & 0x10) == 0);
}
/* (repeated) START */
IICDS = slave | 1;
IICSTAT = 0xB0;
IICCON = 0xF3;
while ((IICCON & 0x10) == 0) wakeup_wait(&i2c_wakeup, 1);
IICCON = 0xB7;
while ((IICCON & 0x10) == 0);
while (len--) {
IICCON = (len == 0) ? 0x73 : 0xF3; /* NACK or ACK */
while ((IICCON & 0x10) == 0) wakeup_wait(&i2c_wakeup, 1);
IICCON = (len == 0) ? 0x37 : 0xB7; /* NACK or ACK */
while ((IICCON & 0x10) == 0);
*data++ = IICDS;
}
/* STOP */
IICSTAT = 0x90;
IICCON = 0xF3;
IICCON = 0xB7;
while ((IICSTAT & (1 << 5)) != 0);
mutex_unlock(&i2c_mtx);