static void uniphier_i2c_hw_init(struct uniphier_i2c_priv *priv,
u32 bus_speed, unsigned long clk_rate)
{
uniphier_i2c_reset(priv, true);
writel((clk_rate / bus_speed / 2 << 16) | (clk_rate / bus_speed),
priv->membase + UNIPHIER_I2C_CLK);
uniphier_i2c_reset(priv, false);
}
static int uniphier_i2c_clk_init(struct device *dev,
struct uniphier_i2c_priv *priv)
{
struct device_node *np = dev->of_node;
unsigned long clk_rate;
u32 bus_speed;
int ret;
if (of_property_read_u32(np, "clock-frequency", &bus_speed))
bus_speed = UNIPHIER_I2C_DEFAULT_SPEED;
if (!bus_speed) {
dev_err(dev, "clock-frequency should not be zero\n");
return -EINVAL;
}
if (bus_speed > UNIPHIER_I2C_MAX_SPEED)
bus_speed = UNIPHIER_I2C_MAX_SPEED;
/* Get input clk rate through clk driver */
priv->clk = devm_clk_get(dev, NULL);
if (IS_ERR(priv->clk)) {
dev_err(dev, "failed to get clock\n");
return PTR_ERR(priv->clk);
}
ret = clk_prepare_enable(priv->clk);
if (ret)
return ret;
clk_rate = clk_get_rate(priv->clk);
if (!clk_rate) {
dev_err(dev, "input clock rate should not be zero\n");
return -EINVAL;
}
uniphier_i2c_reset(priv, true);
writel((clk_rate / bus_speed / 2 << 16) | (clk_rate / bus_speed),
priv->membase + UNIPHIER_I2C_CLK);
uniphier_i2c_reset(priv, false);
return 0;
}
static void uniphier_i2c_unprepare_recovery(struct i2c_adapter *adap)
{
uniphier_i2c_reset(i2c_get_adapdata(adap), false);
}