diff options
| author |   John Keeping <john@metanate.com> | 2020-06-23 13:06:46 +0100 |
|---|---|---|
| committer |   Wolfram Sang <wsa@kernel.org> | 2020-07-04 08:44:39 +0200 |
| commit | f3e2bd713730e6d69e8e021d3ff574f01c39e7e3 (patch) | |
| tree | 8e1a57ab92da844b0b2ca0c28d7a5a0b014ad73e /drivers/i2c | |
| parent | i2c: Use separate MODULE_AUTHOR() statements for multiple authors (diff) | |
| download | wireguard-linux-f3e2bd713730e6d69e8e021d3ff574f01c39e7e3.tar.xz wireguard-linux-f3e2bd713730e6d69e8e021d3ff574f01c39e7e3.zip | |
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 <john@metanate.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-rk3x.c | 39 |
1 files changed, 35 insertions, 4 deletions
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 <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, }; |