On 2017/11/29 11:25, Alan Ott wrote:
The .probe_chip function is supposed to probe an i2c device on the bus to determine whether a device is answering to a particular address. at91_i2c_probe_chip() did not do anything resembling this and always returned 0.
It looks as though at91_i2c_probe_chip() was intended to be a .probe function for the controller, as it was copied-and-pasted to become at91_i2c_probe() in 0bc8f640a4d7ed.
Removing the at91_i2c_probe_chip() function makes the higher layer (i2c_probe_chip()) try a zero-length read transfer to test for the presence of a device instead, which does work.
Signed-off-by: Alan Ott alan@softiron.com
Acked-by: Wenyou Yang wenyou.yang@microchip.com
Thank you for your patch.
drivers/i2c/at91_i2c.c | 22 ---------------------- 1 file changed, 22 deletions(-)
diff --git a/drivers/i2c/at91_i2c.c b/drivers/i2c/at91_i2c.c index 20d0929..7917ca1 100644 --- a/drivers/i2c/at91_i2c.c +++ b/drivers/i2c/at91_i2c.c @@ -201,27 +201,6 @@ static int at91_i2c_enable_clk(struct udevice *dev) return 0; }
-static int at91_i2c_probe_chip(struct udevice *dev, uint chip, uint chip_flags) -{
- struct at91_i2c_bus *bus = dev_get_priv(dev);
- struct at91_i2c_regs *reg = bus->regs;
- int ret;
- ret = at91_i2c_enable_clk(dev);
- if (ret)
return ret;- writel(TWI_CR_SWRST, ®->cr);
- at91_calc_i2c_clock(dev, bus->clock_frequency);
- writel(bus->cwgr_val, ®->cwgr);
- writel(TWI_CR_MSEN, ®->cr);
- writel(TWI_CR_SVDIS, ®->cr);
- return 0;
-}
- static int at91_i2c_set_bus_speed(struct udevice *dev, unsigned int speed) { struct at91_i2c_bus *bus = dev_get_priv(dev);
@@ -256,7 +235,6 @@ static int at91_i2c_ofdata_to_platdata(struct udevice *dev)
static const struct dm_i2c_ops at91_i2c_ops = { .xfer = at91_i2c_xfer,
- .probe_chip = at91_i2c_probe_chip, .set_bus_speed = at91_i2c_set_bus_speed, .get_bus_speed = at91_i2c_get_bus_speed, };
Best Regards, Wenyou Yang