diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c index a4730111d290..2de7452fcd6d 100644 --- a/drivers/i2c/busses/i2c-designware-common.c +++ b/drivers/i2c/busses/i2c-designware-common.c @@ -251,13 +251,27 @@ unsigned long i2c_dw_clk_rate(struct dw_i2c_dev *dev) int i2c_dw_prepare_clk(struct dw_i2c_dev *dev, bool prepare) { + int ret; + if (IS_ERR(dev->clk)) return PTR_ERR(dev->clk); - if (prepare) - return clk_prepare_enable(dev->clk); + if (prepare) { + /* Optional interface clock */ + ret = clk_prepare_enable(dev->pclk); + if (ret) + return ret; + + ret = clk_prepare_enable(dev->clk); + if (ret) + clk_disable_unprepare(dev->pclk); + + return ret; + } clk_disable_unprepare(dev->clk); + clk_disable_unprepare(dev->pclk); + return 0; } EXPORT_SYMBOL_GPL(i2c_dw_prepare_clk); diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h index 6b4ef1d38fb2..67edbbde1070 100644 --- a/drivers/i2c/busses/i2c-designware-core.h +++ b/drivers/i2c/busses/i2c-designware-core.h @@ -177,6 +177,7 @@ * @base: IO registers pointer * @cmd_complete: tx completion indicator * @clk: input reference clock + * @pclk: clock required to access the registers * @slave: represent an I2C slave device * @cmd_err: run time hadware error code * @msgs: points to an array of messages currently being transferred @@ -227,6 +228,7 @@ struct dw_i2c_dev { void __iomem *ext; struct completion cmd_complete; struct clk *clk; + struct clk *pclk; struct reset_control *rst; struct i2c_client *slave; u32 (*get_clk_rate_khz) (struct dw_i2c_dev *dev); diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c index 416f89b8f881..ddfb81872906 100644 --- a/drivers/i2c/busses/i2c-designware-platdrv.c +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -344,6 +344,11 @@ static int dw_i2c_plat_probe(struct platform_device *pdev) else i2c_dw_configure_master(dev); + /* Optional interface clock */ + dev->pclk = devm_clk_get_optional(&pdev->dev, "pclk"); + if (IS_ERR(dev->pclk)) + return PTR_ERR(dev->pclk); + dev->clk = devm_clk_get(&pdev->dev, NULL); if (!i2c_dw_prepare_clk(dev, true)) { u64 clk_khz;