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hw/i2c/bitbang_i2c: Change state calling bitbang_i2c_set_state() helper

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Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Corey Minyard <cminyard@mvista.com>
Message-id: 20230111085016.44551-4-philmd@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Philippe Mathieu-Daudé 2023-01-11 09:50:14 +01:00 committed by Peter Maydell
parent 2b9339d3b4
commit dc575b5e03
1 changed files with 15 additions and 8 deletions
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23
hw/i2c/bitbang_i2c.c
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@ -26,13 +26,19 @@ do { printf("bitbang_i2c: " fmt , ## __VA_ARGS__); } while (0)
#define DPRINTF(fmt, ...) do {} while(0)
#endif
static void bitbang_i2c_set_state(bitbang_i2c_interface *i2c,
bitbang_i2c_state state)
{
i2c->state = state;
}
static void bitbang_i2c_enter_stop(bitbang_i2c_interface *i2c)
{
DPRINTF("STOP\n");
if (i2c->current_addr >= 0)
i2c_end_transfer(i2c->bus);
i2c->current_addr = -1;
i2c->state = STOPPED;
bitbang_i2c_set_state(i2c, STOPPED);
}
/* Set device data pin. */
@ -69,7 +75,7 @@ int bitbang_i2c_set(bitbang_i2c_interface *i2c, int line, int level)
if (level == 0) {
DPRINTF("START\n");
/* START condition. */
i2c->state = SENDING_BIT7;
bitbang_i2c_set_state(i2c, SENDING_BIT7);
i2c->current_addr = -1;
} else {
/* STOP condition. */
@ -96,7 +102,7 @@ int bitbang_i2c_set(bitbang_i2c_interface *i2c, int line, int level)
case SENDING_BIT7 ... SENDING_BIT0:
i2c->buffer = (i2c->buffer << 1) | data;
/* will end up in WAITING_FOR_ACK */
i2c->state++;
bitbang_i2c_set_state(i2c, i2c->state + 1);
return bitbang_i2c_ret(i2c, 1);
case WAITING_FOR_ACK:
@ -117,13 +123,14 @@ int bitbang_i2c_set(bitbang_i2c_interface *i2c, int line, int level)
* device we were sending to decided to NACK us).
*/
DPRINTF("Got NACK\n");
bitbang_i2c_set_state(i2c, SENT_NACK);
bitbang_i2c_enter_stop(i2c);
return bitbang_i2c_ret(i2c, 1);
}
if (i2c->current_addr & 1) {
i2c->state = RECEIVING_BIT7;
bitbang_i2c_set_state(i2c, RECEIVING_BIT7);
} else {
i2c->state = SENDING_BIT7;
bitbang_i2c_set_state(i2c, SENDING_BIT7);
}
return bitbang_i2c_ret(i2c, 0);
}
@ -134,18 +141,18 @@ int bitbang_i2c_set(bitbang_i2c_interface *i2c, int line, int level)
case RECEIVING_BIT6 ... RECEIVING_BIT0:
data = i2c->buffer >> 7;
/* will end up in SENDING_ACK */
i2c->state++;
bitbang_i2c_set_state(i2c, i2c->state + 1);
i2c->buffer <<= 1;
return bitbang_i2c_ret(i2c, data);
case SENDING_ACK:
i2c->state = RECEIVING_BIT7;
if (data != 0) {
DPRINTF("NACKED\n");
i2c->state = SENT_NACK;
bitbang_i2c_set_state(i2c, SENT_NACK);
i2c_nack(i2c->bus);
} else {
DPRINTF("ACKED\n");
bitbang_i2c_set_state(i2c, RECEIVING_BIT7);
}
return bitbang_i2c_ret(i2c, 1);
}