From f3e2bd713730e6d69e8e021d3ff574f01c39e7e3 Mon Sep 17 00:00:00 2001 From: John Keeping Date: Tue, 23 Jun 2020 13:06:46 +0100 Subject: i2c: rk3x: support master_xfer_atomic Enable i2c transactions in irq disabled contexts like poweroff where the PMIC is connected via i2c. Signed-off-by: John Keeping Tested-by: Heiko Stuebner Reviewed-by: Heiko Stuebner Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-rk3x.c | 39 +++++++++++++++++++++++++++++++++++---- 1 file changed, 35 insertions(+), 4 deletions(-) (limited to 'drivers/i2c') diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c index bc698240c4aa..b67bb54caf27 100644 --- a/drivers/i2c/busses/i2c-rk3x.c +++ b/drivers/i2c/busses/i2c-rk3x.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -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, }; -- cgit v1.2.3-59-g8ed1b