Commit f3e2bd71 authored by John Keeping's avatar John Keeping Committed by Wolfram Sang
Browse files

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: default avatarJohn Keeping <john@metanate.com>
Tested-by: default avatarHeiko Stuebner <heiko@sntech.de>
Reviewed-by: default avatarHeiko Stuebner <heiko@sntech.de>
Signed-off-by: default avatarWolfram Sang <wsa@kernel.org>
parent f80531c8

drivers/i2c/busses/i2c-rk3x.c

+35 −4
Original line number Diff line number Diff line
@@ -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);



		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,

};