aboutsummaryrefslogtreecommitdiffstats
path: root/src
diff options
context:
space:
mode:
Diffstat (limited to 'src')
-rw-r--r--src/lpc176x/gpio.h1
-rw-r--r--src/lpc176x/i2c.c109
-rw-r--r--src/lpc176x/internal.h2
3 files changed, 66 insertions, 46 deletions
diff --git a/src/lpc176x/gpio.h b/src/lpc176x/gpio.h
index 97eb909b..482e0ce5 100644
--- a/src/lpc176x/gpio.h
+++ b/src/lpc176x/gpio.h
@@ -39,6 +39,7 @@ void spi_transfer(struct spi_config config, uint8_t receive_data
, uint8_t len, uint8_t *data);
struct i2c_config {
+ void *i2c;
uint8_t addr;
};
diff --git a/src/lpc176x/i2c.c b/src/lpc176x/i2c.c
index ec5d4b50..10b45ede 100644
--- a/src/lpc176x/i2c.c
+++ b/src/lpc176x/i2c.c
@@ -10,51 +10,67 @@
#include "internal.h" // gpio_peripheral
#include "sched.h" // sched_shutdown
+struct i2c_info {
+ LPC_I2C_TypeDef *i2c;
+ uint8_t scl_pin, sda_pin, function, pclk;
+};
+
DECL_ENUMERATION("i2c_bus", "i2c1", 0);
+DECL_ENUMERATION("i2c_bus", "i2c1a", 1);
+DECL_ENUMERATION("i2c_bus", "i2c0", 2);
+DECL_ENUMERATION("i2c_bus", "i2c2", 3);
DECL_CONSTANT_STR("BUS_PINS_i2c1", "P0.1,P0.0");
+DECL_CONSTANT_STR("BUS_PINS_i2c1a", "P0.20,P0.19");
+DECL_CONSTANT_STR("BUS_PINS_i2c0", "P0.28,P0.27");
+DECL_CONSTANT_STR("BUS_PINS_i2c2", "P0.11,P0.10");
+
+static const struct i2c_info i2c_bus[] = {
+ { LPC_I2C1, GPIO(0, 1), GPIO(0, 0), 3, PCLK_I2C1 },
+ { LPC_I2C1, GPIO(0, 20), GPIO(0, 19), 3, PCLK_I2C1 },
+ { LPC_I2C0, GPIO(0, 28), GPIO(0, 27), 1, PCLK_I2C0 },
+ { LPC_I2C2, GPIO(0, 11), GPIO(0, 10), 2, PCLK_I2C2 },
+};
// i2c connection status flags
enum {
IF_START = 1<<5, IF_STOP = 1<<4, IF_IRQ = 1<<3, IF_ACK = 1<<2, IF_ENA = 1<<6
};
-static void
-i2c_init(void)
+struct i2c_config
+i2c_setup(uint32_t bus, uint32_t rate, uint8_t addr)
{
- static int have_run_init;
- if (have_run_init)
- return;
- have_run_init = 1;
+ if (bus >= ARRAY_SIZE(i2c_bus))
+ shutdown("Invalid i2c bus");
- // Init i2c bus 1 pins
- gpio_peripheral(GPIO(0, 1), 3, 0);
- gpio_peripheral(GPIO(0, 0), 3, 0);
+ const struct i2c_info *info = &i2c_bus[bus];
+ LPC_I2C_TypeDef *i2c = info->i2c;
+ static uint8_t have_run_init;
+ if (!(have_run_init & (1 << bus))) {
+ have_run_init |= 1 << bus;
- // Set 100Khz frequency
- enable_pclock(PCLK_I2C1);
- uint32_t pclk = SystemCoreClock, pulse = pclk / (100000 * 2);
- LPC_I2C1->I2SCLL = pulse;
- LPC_I2C1->I2SCLH = pulse;
+ // Init pins
+ gpio_peripheral(info->scl_pin, info->function, 0);
+ gpio_peripheral(info->sda_pin, info->function, 0);
- // Enable interface
- LPC_I2C1->I2CONCLR = IF_START | IF_IRQ | IF_ACK | IF_ENA;
- LPC_I2C1->I2CONSET = IF_ENA;
-}
+ // Set 100Khz frequency
+ enable_pclock(info->pclk);
+ uint32_t pclk = SystemCoreClock, pulse = pclk / (100000 * 2);
+ i2c->I2SCLL = pulse;
+ i2c->I2SCLH = pulse;
-struct i2c_config
-i2c_setup(uint32_t bus, uint32_t rate, uint8_t addr)
-{
- if (bus)
- shutdown("Unsupported i2c bus");
- i2c_init();
- return (struct i2c_config){ .addr=addr<<1 };
+ // Enable interface
+ i2c->I2CONCLR = IF_START | IF_IRQ | IF_ACK | IF_ENA;
+ i2c->I2CONSET = IF_ENA;
+ }
+
+ return (struct i2c_config){ .i2c=i2c, .addr=addr<<1 };
}
static void
-i2c_wait(uint32_t bit, uint32_t timeout)
+i2c_wait(LPC_I2C_TypeDef *i2c, uint32_t bit, uint32_t timeout)
{
for (;;) {
- uint32_t flags = LPC_I2C1->I2CONSET;
+ uint32_t flags = i2c->I2CONSET;
if (flags & bit)
break;
if (!timer_is_before(timer_read_time(), timeout))
@@ -63,44 +79,45 @@ i2c_wait(uint32_t bit, uint32_t timeout)
}
static void
-i2c_start(uint32_t timeout)
+i2c_start(LPC_I2C_TypeDef *i2c, uint32_t timeout)
{
- LPC_I2C1->I2CONCLR = IF_ACK | IF_IRQ | IF_START;
- LPC_I2C1->I2CONSET = IF_ACK | IF_START;
- i2c_wait(IF_IRQ, timeout);
- uint32_t status = LPC_I2C1->I2STAT;
+ i2c->I2CONCLR = IF_ACK | IF_IRQ | IF_START;
+ i2c->I2CONSET = IF_ACK | IF_START;
+ i2c_wait(i2c, IF_IRQ, timeout);
+ uint32_t status = i2c->I2STAT;
if (status != 0x10 && status != 0x08)
shutdown("Failed to send i2c start");
- LPC_I2C1->I2CONCLR = IF_START;
+ i2c->I2CONCLR = IF_START;
}
static uint32_t
-i2c_send_byte(uint8_t b, uint32_t timeout)
+i2c_send_byte(LPC_I2C_TypeDef *i2c, uint8_t b, uint32_t timeout)
{
- LPC_I2C1->I2DAT = b;
- LPC_I2C1->I2CONCLR = IF_IRQ;
- i2c_wait(IF_IRQ, timeout);
- return LPC_I2C1->I2STAT;
+ i2c->I2DAT = b;
+ i2c->I2CONCLR = IF_IRQ;
+ i2c_wait(i2c, IF_IRQ, timeout);
+ return i2c->I2STAT;
}
static void
-i2c_stop(uint32_t timeout)
+i2c_stop(LPC_I2C_TypeDef *i2c, uint32_t timeout)
{
- LPC_I2C1->I2CONSET = IF_STOP;
- LPC_I2C1->I2CONCLR = IF_IRQ;
- i2c_wait(IF_STOP, timeout);
+ i2c->I2CONSET = IF_STOP;
+ i2c->I2CONCLR = IF_IRQ;
+ i2c_wait(i2c, IF_STOP, timeout);
}
void
i2c_write(struct i2c_config config, uint8_t write_len, uint8_t *write)
{
+ LPC_I2C_TypeDef *i2c = config.i2c;
uint32_t timeout = timer_read_time() + timer_from_us(5000);
- i2c_start(timeout);
- i2c_send_byte(config.addr, timeout);
+ i2c_start(i2c, timeout);
+ i2c_send_byte(i2c, config.addr, timeout);
while (write_len--)
- i2c_send_byte(*write++, timeout);
- i2c_stop(timeout);
+ i2c_send_byte(i2c, *write++, timeout);
+ i2c_stop(i2c, timeout);
}
void
diff --git a/src/lpc176x/internal.h b/src/lpc176x/internal.h
index 2a1d0150..a8253138 100644
--- a/src/lpc176x/internal.h
+++ b/src/lpc176x/internal.h
@@ -10,10 +10,12 @@
#define PCLK_TIMER0 1
#define PCLK_UART0 3
+#define PCLK_I2C0 7
#define PCLK_SSP1 10
#define PCLK_ADC 12
#define PCLK_I2C1 19
#define PCLK_SSP0 21
+#define PCLK_I2C2 26
#define PCLK_USB 31
int is_enabled_pclock(uint32_t pclk);
void enable_pclock(uint32_t pclk);
generated by cgit v1.2.3-70-g09d2 (git 2.50.1) at 2025-09-02 08:17:49 +0000