static void
mv_twsi_cal_baud_rate(const uint32_t target, struct mv_twsi_baud_rate *rate)
{
uint32_t clk, cur, diff, diff0;
int m, n, m0, n0;
/* Calculate baud rate. */
m0 = n0 = 4; /* Default values on reset */
diff0 = 0xffffffff;
clk = get_tclk();
for (n = 0; n < 8; n++) {
for (m = 0; m < 16; m++) {
cur = TWSI_BAUD_RATE_RAW(clk,m,n);
diff = ABSSUB(target, cur);
if (diff < diff0) {
m0 = m;
n0 = n;
diff0 = diff;
}
}
}
rate->raw = TWSI_BAUD_RATE_RAW(clk, m0, n0);
rate->param = TWSI_BAUD_RATE_PARAM(m0, n0);
rate->m = m0;
rate->n = n0;
}
static int
a10_twsi_attach(device_t dev)
{
struct twsi_softc *sc;
clk_t clk;
hwreset_t rst;
int error;
sc = device_get_softc(dev);
/* De-assert reset */
if (hwreset_get_by_ofw_idx(dev, 0, &rst) == 0) {
error = hwreset_deassert(rst);
if (error != 0) {
device_printf(dev, "could not de-assert reset\n");
return (error);
}
}
/* Activate clock */
error = clk_get_by_ofw_index(dev, 0, &clk);
if (error != 0) {
device_printf(dev, "could not find clock\n");
return (error);
}
error = clk_enable(clk);
if (error != 0) {
device_printf(dev, "could not enable clock\n");
return (error);
}
sc->reg_data = TWI_DATA;
sc->reg_slave_addr = TWI_ADDR;
sc->reg_slave_ext_addr = TWI_XADDR;
sc->reg_control = TWI_CNTR;
sc->reg_status = TWI_STAT;
sc->reg_baud_rate = TWI_CCR;
sc->reg_soft_reset = TWI_SRST;
/* Setup baud rate params */
sc->baud_rate[IIC_SLOW].param = TWSI_BAUD_RATE_PARAM(11, 2);
sc->baud_rate[IIC_FAST].param = TWSI_BAUD_RATE_PARAM(11, 2);
sc->baud_rate[IIC_FASTEST].param = TWSI_BAUD_RATE_PARAM(2, 2);
return (twsi_attach(dev));
}
static int
a10_twsi_attach(device_t dev)
{
struct twsi_softc *sc;
int clk;
sc = device_get_softc(dev);
/* Activate clock */
switch (ofw_bus_search_compatible(dev, compat_data)->ocd_data) {
#if defined(SOC_ALLWINNER_A10) || defined(SOC_ALLWINNER_A20)
case A10_I2C:
clk = a10_clk_i2c_activate(device_get_unit(dev));
break;
#endif
#if defined(SOC_ALLWINNER_A31) || defined(SOC_ALLWINNER_A31S)
case A31_I2C:
clk = a31_clk_i2c_activate(device_get_unit(dev));
break;
#endif
default:
clk = -1;
}
if (clk != 0) {
device_printf(dev, "could not activate i2c clock\n");
return (ENXIO);
}
sc->reg_data = TWI_DATA;
sc->reg_slave_addr = TWI_ADDR;
sc->reg_slave_ext_addr = TWI_XADDR;
sc->reg_control = TWI_CNTR;
sc->reg_status = TWI_STAT;
sc->reg_baud_rate = TWI_CCR;
sc->reg_soft_reset = TWI_SRST;
/* Setup baud rate params */
sc->baud_rate[IIC_SLOW].param = TWSI_BAUD_RATE_PARAM(11, 2);
sc->baud_rate[IIC_FAST].param = TWSI_BAUD_RATE_PARAM(11, 2);
sc->baud_rate[IIC_FASTEST].param = TWSI_BAUD_RATE_PARAM(2, 2);
return (twsi_attach(dev));
}