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i2c: exynos5: add support for atomic transfers

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Add support for atomic transfers using polling mode with interrupts
intentionally disabled. This removes the warning introduced by commit
63b96983a5 ("i2c: core: introduce callbacks for atomic transfers")
during system reboot and power-off.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
This commit is contained in:
Marek Szyprowski 2023-10-06 17:08:03 +02:00 • committed by Wolfram Sang
parent 29c9e85d4d
commit 445094c8a9
1 changed files with 44 additions and 2 deletions
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42
drivers/i2c/busses/i2c-exynos5.c
View file

@ -194,6 +194,11 @@ struct exynos5_i2c {
*/ */
int trans_done; int trans_done;
/*
* Called from atomic context, don't use interrupts.
*/
unsigned int atomic;
/* Controller operating frequency */ /* Controller operating frequency */
unsigned int op_clock; unsigned int op_clock;
@ -711,6 +716,22 @@ static void exynos5_i2c_message_start(struct exynos5_i2c *i2c, int stop)
spin_unlock_irqrestore(&i2c->lock, flags); spin_unlock_irqrestore(&i2c->lock, flags);
} }
static bool exynos5_i2c_poll_irqs_timeout(struct exynos5_i2c *i2c,
unsigned long timeout)
{
unsigned long time_left = jiffies + timeout;
while (time_before(jiffies, time_left) &&
!((i2c->trans_done && (i2c->msg->len == i2c->msg_ptr)) ||
(i2c->state < 0))) {
while (readl(i2c->regs + HSI2C_INT_ENABLE) &
readl(i2c->regs + HSI2C_INT_STATUS))
exynos5_i2c_irq(i2c->irq, i2c);
usleep_range(100, 200);
}
return time_before(jiffies, time_left);
}
static int exynos5_i2c_xfer_msg(struct exynos5_i2c *i2c, static int exynos5_i2c_xfer_msg(struct exynos5_i2c *i2c,
struct i2c_msg *msgs, int stop) struct i2c_msg *msgs, int stop)
{ {
@ -725,8 +746,13 @@ static int exynos5_i2c_xfer_msg(struct exynos5_i2c *i2c,
exynos5_i2c_message_start(i2c, stop); exynos5_i2c_message_start(i2c, stop);
if (!i2c->atomic)
timeout = wait_for_completion_timeout(&i2c->msg_complete, timeout = wait_for_completion_timeout(&i2c->msg_complete,
EXYNOS5_I2C_TIMEOUT); EXYNOS5_I2C_TIMEOUT);
else
timeout = exynos5_i2c_poll_irqs_timeout(i2c,
EXYNOS5_I2C_TIMEOUT);
if (timeout == 0) if (timeout == 0)
ret = -ETIMEDOUT; ret = -ETIMEDOUT;
else else
@ -777,6 +803,21 @@ err_pclk:
return ret ?: num; return ret ?: num;
} }
static int exynos5_i2c_xfer_atomic(struct i2c_adapter *adap,
struct i2c_msg *msgs, int num)
{
struct exynos5_i2c *i2c = adap->algo_data;
int ret;
disable_irq(i2c->irq);
i2c->atomic = true;
ret = exynos5_i2c_xfer(adap, msgs, num);
i2c->atomic = false;
enable_irq(i2c->irq);
return ret;
}
static u32 exynos5_i2c_func(struct i2c_adapter *adap) static u32 exynos5_i2c_func(struct i2c_adapter *adap)
{ {
return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
@ -784,6 +825,7 @@ static u32 exynos5_i2c_func(struct i2c_adapter *adap)
static const struct i2c_algorithm exynos5_i2c_algorithm = { static const struct i2c_algorithm exynos5_i2c_algorithm = {
.master_xfer = exynos5_i2c_xfer, .master_xfer = exynos5_i2c_xfer,
.master_xfer_atomic = exynos5_i2c_xfer_atomic,
.functionality = exynos5_i2c_func, .functionality = exynos5_i2c_func,
}; };