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i2c: designware: Don't set SCL timings and speed mode when in slave mode

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According to data sheet SCL timing parameters and DW_IC_CON SPEED mode
bits are not used when operating in slave mode.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Luis Oliveira <lolivei@synopsys.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Jarkko Nikula 2017-08-23 16:46:12 +03:00 committed by Wolfram Sang
parent 4fbd8d194f
commit 43df43e6ba
2 changed files with 0 additions and 75 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

11
drivers/i2c/busses/i2c-designware-platdrv.c
View file

@ -201,17 +201,6 @@ static void i2c_dw_configure_slave(struct dw_i2c_dev *dev)
DW_IC_CON_RESTART_EN | DW_IC_CON_STOP_DET_IFADDRESSED;
dev->mode = DW_IC_SLAVE;
switch (dev->clk_freq) {
case 100000:
dev->slave_cfg |= DW_IC_CON_SPEED_STD;
break;
case 3400000:
dev->slave_cfg |= DW_IC_CON_SPEED_HIGH;
break;
default:
dev->slave_cfg |= DW_IC_CON_SPEED_FAST;
}
}
static int i2c_dw_plat_prepare_clk(struct dw_i2c_dev *i_dev, bool prepare)

64
drivers/i2c/busses/i2c-designware-slave.c
View file

@ -51,9 +51,7 @@ static void i2c_dw_configure_fifo_slave(struct dw_i2c_dev *dev)
*/
static int i2c_dw_init_slave(struct dw_i2c_dev *dev)
{
u32 sda_falling_time, scl_falling_time;
u32 reg, comp_param1;
u32 hcnt, lcnt;
int ret;
ret = i2c_dw_acquire_lock(dev);
@ -79,68 +77,6 @@ static int i2c_dw_init_slave(struct dw_i2c_dev *dev)
/* Disable the adapter. */
__i2c_dw_enable_and_wait(dev, false);
/* Set standard and fast speed deviders for high/low periods. */
sda_falling_time = dev->sda_falling_time ?: 300; /* ns */
scl_falling_time = dev->scl_falling_time ?: 300; /* ns */
/* Set SCL timing parameters for standard-mode. */
if (dev->ss_hcnt && dev->ss_lcnt) {
hcnt = dev->ss_hcnt;
lcnt = dev->ss_lcnt;
} else {
hcnt = i2c_dw_scl_hcnt(i2c_dw_clk_rate(dev),
4000, /* tHD;STA = tHIGH = 4.0 us */
sda_falling_time,
0, /* 0: DW default, 1: Ideal */
0); /* No offset */
lcnt = i2c_dw_scl_lcnt(i2c_dw_clk_rate(dev),
4700, /* tLOW = 4.7 us */
scl_falling_time,
0); /* No offset */
}
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);
/* Set SCL timing parameters for fast-mode or fast-mode plus. */
if ((dev->clk_freq == 1000000) && dev->fp_hcnt && dev->fp_lcnt) {
hcnt = dev->fp_hcnt;
lcnt = dev->fp_lcnt;
} else if (dev->fs_hcnt && dev->fs_lcnt) {
hcnt = dev->fs_hcnt;
lcnt = dev->fs_lcnt;
} else {
hcnt = i2c_dw_scl_hcnt(i2c_dw_clk_rate(dev),
600, /* tHD;STA = tHIGH = 0.6 us */
sda_falling_time,
0, /* 0: DW default, 1: Ideal */
0); /* No offset */
lcnt = i2c_dw_scl_lcnt(i2c_dw_clk_rate(dev),
1300, /* tLOW = 1.3 us */
scl_falling_time,
0); /* No offset */
}
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);
if ((dev->slave_cfg & DW_IC_CON_SPEED_MASK) ==
DW_IC_CON_SPEED_HIGH) {
if ((comp_param1 & DW_IC_COMP_PARAM_1_SPEED_MODE_MASK)
!= DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH) {
dev_err(dev->dev, "High Speed not supported!\n");
dev->slave_cfg &= ~DW_IC_CON_SPEED_MASK;
dev->slave_cfg |= DW_IC_CON_SPEED_FAST;
} else if (dev->hs_hcnt && dev->hs_lcnt) {
hcnt = dev->hs_hcnt;
lcnt = dev->hs_lcnt;
dw_writel(dev, hcnt, DW_IC_HS_SCL_HCNT);
dw_writel(dev, lcnt, DW_IC_HS_SCL_LCNT);
dev_dbg(dev->dev, "HighSpeed-mode HCNT:LCNT = %d:%d\n",
hcnt, lcnt);
}
}
/* Configure SDA Hold Time if required. */
reg = dw_readl(dev, DW_IC_COMP_VERSION);
if (reg >= DW_IC_SDA_HOLD_MIN_VERS) {