diff options
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-core.c | 11 | ||||
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-core.h | 12 |
2 files changed, 23 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c index f325ec7abfb1..dbecf08399f8 100644 --- a/drivers/i2c/busses/i2c-designware-core.c +++ b/drivers/i2c/busses/i2c-designware-core.c @@ -317,6 +317,12 @@ int i2c_dw_init(struct dw_i2c_dev *dev) 47, /* tLOW = 4.7 us */ 3, /* tf = 0.3 us */ 0); /* No offset */ + + /* Allow platforms to specify the ideal HCNT and LCNT values */ + if (dev->ss_hcnt && dev->ss_lcnt) { + hcnt = dev->ss_hcnt; + lcnt = dev->ss_lcnt; + } dw_writel(dev, hcnt, DW_IC_SS_SCL_HCNT); dw_writel(dev, lcnt, DW_IC_SS_SCL_LCNT); dev_dbg(dev->dev, "Standard-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt); @@ -331,6 +337,11 @@ int i2c_dw_init(struct dw_i2c_dev *dev) 13, /* tLOW = 1.3 us */ 3, /* tf = 0.3 us */ 0); /* No offset */ + + if (dev->fs_hcnt && dev->fs_lcnt) { + hcnt = dev->fs_hcnt; + lcnt = dev->fs_lcnt; + } dw_writel(dev, hcnt, DW_IC_FS_SCL_HCNT); dw_writel(dev, lcnt, DW_IC_FS_SCL_LCNT); dev_dbg(dev->dev, "Fast-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt); diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h index 912aa2262866..e8a756537ed0 100644 --- a/drivers/i2c/busses/i2c-designware-core.h +++ b/drivers/i2c/busses/i2c-designware-core.h @@ -61,6 +61,14 @@ * @tx_fifo_depth: depth of the hardware tx fifo * @rx_fifo_depth: depth of the hardware rx fifo * @rx_outstanding: current master-rx elements in tx fifo + * @ss_hcnt: standard speed HCNT value + * @ss_lcnt: standard speed LCNT value + * @fs_hcnt: fast speed HCNT value + * @fs_lcnt: fast speed LCNT value + * + * HCNT and LCNT parameters can be used if the platform knows more accurate + * values than the one computed based only on the input clock frequency. + * Leave them to be %0 if not used. */ struct dw_i2c_dev { struct device *dev; @@ -91,6 +99,10 @@ struct dw_i2c_dev { unsigned int rx_fifo_depth; int rx_outstanding; u32 sda_hold_time; + u16 ss_hcnt; + u16 ss_lcnt; + u16 fs_hcnt; + u16 fs_lcnt; }; #define ACCESS_SWAP 0x00000001 |