Am Dienstag, 23. Juni 2020, 14:06:46 CEST schrieb John Keeping: > Enable i2c transactions in irq disabled contexts like poweroff where the > PMIC is connected via i2c. > > Signed-off-by: John Keeping <[email protected]>
on a rk3288: Tested-by: Heiko Stuebner <[email protected]> Reviewed-by: Heiko Stuebner <[email protected]> > --- > drivers/i2c/busses/i2c-rk3x.c | 39 +++++++++++++++++++++++++++++++---- > 1 file changed, 35 insertions(+), 4 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c > index 15324bfbc6cb..8e3cc85d1921 100644 > --- a/drivers/i2c/busses/i2c-rk3x.c > +++ b/drivers/i2c/busses/i2c-rk3x.c > @@ -10,6 +10,7 @@ > #include <linux/module.h> > #include <linux/i2c.h> > #include <linux/interrupt.h> > +#include <linux/iopoll.h> > #include <linux/errno.h> > #include <linux/err.h> > #include <linux/platform_device.h> > @@ -1040,8 +1041,21 @@ static int rk3x_i2c_setup(struct rk3x_i2c *i2c, struct > i2c_msg *msgs, int num) > return ret; > } > > -static int rk3x_i2c_xfer(struct i2c_adapter *adap, > - struct i2c_msg *msgs, int num) > +static int rk3x_i2c_wait_xfer_poll(struct rk3x_i2c *i2c) > +{ > + ktime_t timeout = ktime_add_ms(ktime_get(), WAIT_TIMEOUT); > + > + while (READ_ONCE(i2c->busy) && > + ktime_compare(ktime_get(), timeout) < 0) { > + udelay(5); > + rk3x_i2c_irq(0, i2c); > + } > + > + return !i2c->busy; > +} > + > +static int rk3x_i2c_xfer_common(struct i2c_adapter *adap, > + struct i2c_msg *msgs, int num, bool polling) > { > struct rk3x_i2c *i2c = (struct rk3x_i2c *)adap->algo_data; > unsigned long timeout, flags; > @@ -1075,8 +1089,12 @@ static int rk3x_i2c_xfer(struct i2c_adapter *adap, > > rk3x_i2c_start(i2c); > > - timeout = wait_event_timeout(i2c->wait, !i2c->busy, > - msecs_to_jiffies(WAIT_TIMEOUT)); > + if (!polling) { > + timeout = wait_event_timeout(i2c->wait, !i2c->busy, > + > msecs_to_jiffies(WAIT_TIMEOUT)); > + } else { > + timeout = rk3x_i2c_wait_xfer_poll(i2c); > + } > > spin_lock_irqsave(&i2c->lock, flags); > > @@ -1110,6 +1128,18 @@ static int rk3x_i2c_xfer(struct i2c_adapter *adap, > return ret < 0 ? ret : num; > } > > +static int rk3x_i2c_xfer(struct i2c_adapter *adap, > + struct i2c_msg *msgs, int num) > +{ > + return rk3x_i2c_xfer_common(adap, msgs, num, false); > +} > + > +static int rk3x_i2c_xfer_polling(struct i2c_adapter *adap, > + struct i2c_msg *msgs, int num) > +{ > + return rk3x_i2c_xfer_common(adap, msgs, num, true); > +} > + > static __maybe_unused int rk3x_i2c_resume(struct device *dev) > { > struct rk3x_i2c *i2c = dev_get_drvdata(dev); > @@ -1126,6 +1156,7 @@ static u32 rk3x_i2c_func(struct i2c_adapter *adap) > > static const struct i2c_algorithm rk3x_i2c_algorithm = { > .master_xfer = rk3x_i2c_xfer, > + .master_xfer_atomic = rk3x_i2c_xfer_polling, > .functionality = rk3x_i2c_func, > }; > >
