Message ID | 20240913101445.16513-5-kfting@nuvoton.com |
---|---|
State | New |
Headers | show |
Series | i2c: npcm: Bug fixes read/write operation, checkpatch | expand |
On Fri, Sep 13, 2024 at 06:14:44PM +0800, warp5tw@gmail.com wrote: > From: Tyrone Ting <kfting@nuvoton.com> > > Store the client address earlier since it might get called in > the i2c_recover_bus logic flow at the early stage of the function > npcm_i2c_master_xfer. We refer to the functions as func(). ... > + /* > + * Previously, the address was stored w/o left-shift by one bit and > + * with that shift in the following call to npcm_i2c_master_start_xmit. > + * > + * Since there are cases that the i2c_recover_bus gets called at the > + * early stage of the function npcm_i2c_master_xfer, the address is Ditto. > + * stored with the shift and used in the i2c_recover_bus call. > + * > + * The address is stored from bit 1 to bit 7 in the register for > + * sending the i2c address later so it's left-shifted by 1 bit. > + */
Hi Andy: Your comments will be addressed. Andy Shevchenko <andriy.shevchenko@linux.intel.com> 於 2024年9月13日 週五 下午6:33寫道: > > On Fri, Sep 13, 2024 at 06:14:44PM +0800, warp5tw@gmail.com wrote: > > From: Tyrone Ting <kfting@nuvoton.com> > > > > Store the client address earlier since it might get called in > > the i2c_recover_bus logic flow at the early stage of the function > > npcm_i2c_master_xfer. > > We refer to the functions as func(). > > ... > > > + /* > > + * Previously, the address was stored w/o left-shift by one bit and > > + * with that shift in the following call to npcm_i2c_master_start_xmit. > > + * > > + * Since there are cases that the i2c_recover_bus gets called at the > > + * early stage of the function npcm_i2c_master_xfer, the address is > > Ditto. > > > + * stored with the shift and used in the i2c_recover_bus call. > > + * > > + * The address is stored from bit 1 to bit 7 in the register for > > + * sending the i2c address later so it's left-shifted by 1 bit. > > + */ > > > -- > With Best Regards, > Andy Shevchenko > > Thank you. Regards, Tyrone
diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c index 68f3d47323ab..e52e65e63600 100644 --- a/drivers/i2c/busses/i2c-npcm7xx.c +++ b/drivers/i2c/busses/i2c-npcm7xx.c @@ -2155,6 +2155,18 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, } while (time_is_after_jiffies(time_left) && bus_busy); + /* + * Previously, the address was stored w/o left-shift by one bit and + * with that shift in the following call to npcm_i2c_master_start_xmit. + * + * Since there are cases that the i2c_recover_bus gets called at the + * early stage of the function npcm_i2c_master_xfer, the address is + * stored with the shift and used in the i2c_recover_bus call. + * + * The address is stored from bit 1 to bit 7 in the register for + * sending the i2c address later so it's left-shifted by 1 bit. + */ + bus->dest_addr = slave_addr << 1; if (bus_busy || bus->ber_state) { iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST); npcm_i2c_reset(bus); @@ -2163,7 +2175,6 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, } npcm_i2c_init_params(bus); - bus->dest_addr = slave_addr; bus->msgs = msgs; bus->msgs_num = num; bus->cmd_err = 0;