Hi Sascha, On Tue, 2015-03-31 at 15:08 +0800, Eddie Huang wrote: > Hi Sascha, > > On Mon, 2015-03-30 at 19:23 +0200, Sascha Hauer wrote: > > On Mon, Mar 30, 2015 at 04:14:12PM +0800, Eddie Huang wrote: > > > Hi Sascha, > > > > > > > > > > > [...] > > > > > > > > > + if (i2c->speed_hz > 400000) > > > > > + control_reg |= I2C_CONTROL_RS; > > > > > + if (i2c->op == I2C_MASTER_WRRD) > > > > > + control_reg |= I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS; > > > > > + mtk_i2c_writew(control_reg, i2c, OFFSET_CONTROL); > > > > > + > > > > > + /* set start condition */ > > > > > + if (i2c->speed_hz <= 100000) > > > > > + mtk_i2c_writew(I2C_ST_START_CON, i2c, OFFSET_EXT_CONF); > > > > > + else > > > > > + mtk_i2c_writew(I2C_FS_START_CON, i2c, OFFSET_EXT_CONF); > > > > > + > > > > > + if (~control_reg & I2C_CONTROL_RS) > > > > > + mtk_i2c_writew(I2C_DELAY_LEN, i2c, OFFSET_DELAY_LEN); > > > > > > > > speed <= 400000 here to make this more obvious? > > > There are two cases, not only speed<=400000, but I2C_MASTER_WRRD. I tend > > > to keep it. > > > > Still it looks strange. You only ever write this default value to the > > register. Putting this register write under an if() seems bogus since > > the same value will be in the register the next time this code is > > executed. It looks like you should move this register write to some > > initialization function. > OK, move to mtk_i2c_init_hw function > Sorry for my negligence. Write-then-read (I2C_MASTER_WRRD) decides according to each I2C transfer, so I still need to judge whether set I2C_CONTROL_RS and DELAY_LEN here. Other control setting can move to init function. Eddie -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
