diff options
Diffstat (limited to 'drivers/i2c')
-rw-r--r-- | drivers/i2c/busses/i2c-designware-common.c | 27 | ||||
-rw-r--r-- | drivers/i2c/busses/i2c-designware-core.h | 6 | ||||
-rw-r--r-- | drivers/i2c/busses/i2c-designware-master.c | 32 |
3 files changed, 53 insertions, 12 deletions
diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c index e8a688d04aee..4160c5e57df4 100644 --- a/drivers/i2c/busses/i2c-designware-common.c +++ b/drivers/i2c/busses/i2c-designware-common.c @@ -332,8 +332,27 @@ void i2c_dw_adjust_bus_speed(struct dw_i2c_dev *dev) } EXPORT_SYMBOL_GPL(i2c_dw_adjust_bus_speed); -u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset) +static u32 i2c_dw_read_scl_reg(struct dw_i2c_dev *dev, u32 reg) { + u32 val; + int ret; + + ret = i2c_dw_acquire_lock(dev); + if (ret) + return 0; + + ret = regmap_read(dev->map, reg, &val); + i2c_dw_release_lock(dev); + + return ret ? 0 : val; +} + +u32 i2c_dw_scl_hcnt(struct dw_i2c_dev *dev, unsigned int reg, u32 ic_clk, + u32 tSYMBOL, u32 tf, int cond, int offset) +{ + if (!ic_clk) + return i2c_dw_read_scl_reg(dev, reg); + /* * DesignWare I2C core doesn't seem to have solid strategy to meet * the tHD;STA timing spec. Configuring _HCNT based on tHIGH spec @@ -372,8 +391,12 @@ u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset) 3 + offset; } -u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset) +u32 i2c_dw_scl_lcnt(struct dw_i2c_dev *dev, unsigned int reg, u32 ic_clk, + u32 tLOW, u32 tf, int offset) { + if (!ic_clk) + return i2c_dw_read_scl_reg(dev, reg); + /* * Conditional expression: * diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h index e9606c00b8d1..3e48f446ce53 100644 --- a/drivers/i2c/busses/i2c-designware-core.h +++ b/drivers/i2c/busses/i2c-designware-core.h @@ -329,8 +329,10 @@ struct i2c_dw_semaphore_callbacks { }; int i2c_dw_init_regmap(struct dw_i2c_dev *dev); -u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset); -u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset); +u32 i2c_dw_scl_hcnt(struct dw_i2c_dev *dev, unsigned int reg, u32 ic_clk, + u32 tSYMBOL, u32 tf, int cond, int offset); +u32 i2c_dw_scl_lcnt(struct dw_i2c_dev *dev, unsigned int reg, u32 ic_clk, + u32 tLOW, u32 tf, int offset); int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev); u32 i2c_dw_clk_rate(struct dw_i2c_dev *dev); int i2c_dw_prepare_clk(struct dw_i2c_dev *dev, bool prepare); diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c index c7e56002809a..d3b466592be4 100644 --- a/drivers/i2c/busses/i2c-designware-master.c +++ b/drivers/i2c/busses/i2c-designware-master.c @@ -64,13 +64,17 @@ static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev) if (!dev->ss_hcnt || !dev->ss_lcnt) { ic_clk = i2c_dw_clk_rate(dev); dev->ss_hcnt = - i2c_dw_scl_hcnt(ic_clk, + i2c_dw_scl_hcnt(dev, + DW_IC_SS_SCL_HCNT, + ic_clk, 4000, /* tHD;STA = tHIGH = 4.0 us */ sda_falling_time, 0, /* 0: DW default, 1: Ideal */ 0); /* No offset */ dev->ss_lcnt = - i2c_dw_scl_lcnt(ic_clk, + i2c_dw_scl_lcnt(dev, + DW_IC_SS_SCL_LCNT, + ic_clk, 4700, /* tLOW = 4.7 us */ scl_falling_time, 0); /* No offset */ @@ -94,13 +98,17 @@ static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev) } else { ic_clk = i2c_dw_clk_rate(dev); dev->fs_hcnt = - i2c_dw_scl_hcnt(ic_clk, + i2c_dw_scl_hcnt(dev, + DW_IC_FS_SCL_HCNT, + ic_clk, 260, /* tHIGH = 260 ns */ sda_falling_time, 0, /* DW default */ 0); /* No offset */ dev->fs_lcnt = - i2c_dw_scl_lcnt(ic_clk, + i2c_dw_scl_lcnt(dev, + DW_IC_FS_SCL_LCNT, + ic_clk, 500, /* tLOW = 500 ns */ scl_falling_time, 0); /* No offset */ @@ -114,13 +122,17 @@ static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev) if (!dev->fs_hcnt || !dev->fs_lcnt) { ic_clk = i2c_dw_clk_rate(dev); dev->fs_hcnt = - i2c_dw_scl_hcnt(ic_clk, + i2c_dw_scl_hcnt(dev, + DW_IC_FS_SCL_HCNT, + ic_clk, 600, /* tHD;STA = tHIGH = 0.6 us */ sda_falling_time, 0, /* 0: DW default, 1: Ideal */ 0); /* No offset */ dev->fs_lcnt = - i2c_dw_scl_lcnt(ic_clk, + i2c_dw_scl_lcnt(dev, + DW_IC_FS_SCL_LCNT, + ic_clk, 1300, /* tLOW = 1.3 us */ scl_falling_time, 0); /* No offset */ @@ -142,13 +154,17 @@ static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev) } else if (!dev->hs_hcnt || !dev->hs_lcnt) { ic_clk = i2c_dw_clk_rate(dev); dev->hs_hcnt = - i2c_dw_scl_hcnt(ic_clk, + i2c_dw_scl_hcnt(dev, + DW_IC_HS_SCL_HCNT, + ic_clk, 160, /* tHIGH = 160 ns */ sda_falling_time, 0, /* DW default */ 0); /* No offset */ dev->hs_lcnt = - i2c_dw_scl_lcnt(ic_clk, + i2c_dw_scl_lcnt(dev, + DW_IC_HS_SCL_LCNT, + ic_clk, 320, /* tLOW = 320 ns */ scl_falling_time, 0); /* No offset */ |