diff options
| author | Phil Edworthy <phil.edworthy@renesas.com> | 2019-02-28 16:52:10 +0300 |
|---|---|---|
| committer | Wolfram Sang <wsa@the-dreams.de> | 2019-03-20 19:57:18 +0300 |
| commit | c62ebb3d5f0d0e9dafe990c9ce680ca9b46fd4c1 (patch) | |
| tree | 2f3d3a2dcbbda1b6fcd46b9fe193071641d2d0f4 /drivers/i2c/busses/i2c-designware-common.c | |
| parent | bdfdf4b2ba644347d63a61da941f30aea1bd35fc (diff) | |
| download | linux-c62ebb3d5f0d0e9dafe990c9ce680ca9b46fd4c1.tar.xz | |
i2c: designware: Add support for an interface clock
The Synopsys I2C Controller has an interface clock, but most SoCs hide
this away. However, on some SoCs you need to explicitly enable the
interface clock in order to access the registers. Therefore, add
support for an optional interface clock.
Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Gareth Williams <gareth.williams.jx@renesas.com>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c/busses/i2c-designware-common.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-common.c | 18 |
1 files changed, 16 insertions, 2 deletions
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); |