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authorMarek Szyprowski <m.szyprowski@samsung.com>2023-10-06 18:08:03 +0300
committerWolfram Sang <wsa@kernel.org>2023-10-21 21:45:41 +0300
commit445094c8a9fb1ea644aa4e78ba47ccad1cf6c9f5 (patch)
tree7ddc9a0eea3d33e6eeb518da1b4a73d9c467d222 /drivers/i2c
parent29c9e85d4da2b401b430aa0989932992431745ec (diff)
downloadlinux-445094c8a9fb1ea644aa4e78ba47ccad1cf6c9f5.tar.xz
i2c: exynos5: add support for atomic transfers
Add support for atomic transfers using polling mode with interrupts intentionally disabled. This removes the warning introduced by commit 63b96983a5dd ("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>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-exynos5.c46
1 files changed, 44 insertions, 2 deletions
diff --git a/drivers/i2c/busses/i2c-exynos5.c b/drivers/i2c/busses/i2c-exynos5.c
index 2b0b9cdffa86..65cb06ec3804 100644
--- a/drivers/i2c/busses/i2c-exynos5.c
+++ b/drivers/i2c/busses/i2c-exynos5.c
@@ -194,6 +194,11 @@ struct exynos5_i2c {
*/
int trans_done;
+ /*
+ * Called from atomic context, don't use interrupts.
+ */
+ unsigned int atomic;
+
/* Controller operating frequency */
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);
}
+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,
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);
- timeout = wait_for_completion_timeout(&i2c->msg_complete,
- EXYNOS5_I2C_TIMEOUT);
+ if (!i2c->atomic)
+ timeout = wait_for_completion_timeout(&i2c->msg_complete,
+ EXYNOS5_I2C_TIMEOUT);
+ else
+ timeout = exynos5_i2c_poll_irqs_timeout(i2c,
+ EXYNOS5_I2C_TIMEOUT);
+
if (timeout == 0)
ret = -ETIMEDOUT;
else
@@ -777,6 +803,21 @@ err_pclk:
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)
{
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 = {
.master_xfer = exynos5_i2c_xfer,
+ .master_xfer_atomic = exynos5_i2c_xfer_atomic,
.functionality = exynos5_i2c_func,
};