diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-xlp9xx.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-xlp9xx.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/drivers/i2c/busses/i2c-xlp9xx.c b/drivers/i2c/busses/i2c-xlp9xx.c index 6b106e94bc09..f0bef2d5306c 100644 --- a/drivers/i2c/busses/i2c-xlp9xx.c +++ b/drivers/i2c/busses/i2c-xlp9xx.c @@ -7,6 +7,7 @@ */ #include <linux/acpi.h> +#include <linux/clk.h> #include <linux/completion.h> #include <linux/i2c.h> #include <linux/init.h> @@ -84,6 +85,7 @@ struct xlp9xx_i2c_dev { u32 __iomem *base; u32 msg_buf_remaining; u32 msg_len; + u32 ip_clk_hz; u32 clk_hz; u32 msg_err; u8 *msg_buf; @@ -213,7 +215,7 @@ static int xlp9xx_i2c_init(struct xlp9xx_i2c_dev *priv) * The controller uses 5 * SCL clock internally. * So prescale value should be divided by 5. */ - prescale = DIV_ROUND_UP(XLP9XX_I2C_IP_CLK_FREQ, priv->clk_hz); + prescale = DIV_ROUND_UP(priv->ip_clk_hz, priv->clk_hz); prescale = ((prescale - 8) / 5) - 1; xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, XLP9XX_I2C_CTRL_RST); xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, XLP9XX_I2C_CTRL_EN | @@ -342,9 +344,19 @@ static const struct i2c_algorithm xlp9xx_i2c_algo = { static int xlp9xx_i2c_get_frequency(struct platform_device *pdev, struct xlp9xx_i2c_dev *priv) { + struct clk *clk; u32 freq; int err; + clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(clk)) { + priv->ip_clk_hz = XLP9XX_I2C_IP_CLK_FREQ; + dev_dbg(&pdev->dev, "using default input frequency %u\n", + priv->ip_clk_hz); + } else { + priv->ip_clk_hz = clk_get_rate(clk); + } + err = device_property_read_u32(&pdev->dev, "clock-frequency", &freq); if (err) { freq = XLP9XX_I2C_DEFAULT_FREQ; |